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1. (WO2019043665) MANUFACTURING MACHINE FOR THE PRODUCTION OF DISPOSABLE CARTRIDGES FOR ELECTRONIC CIGARETTES
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"MANUFACTURING MACHINE FOR THE PRODUCTION OF DISPOSABLE CARTRIDGES FOR ELECTRONIC CIGARETTES"

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from Italian Patent

Application No. 102017000098827 filed on September 4, 2017, the disclosure of which is incorporated by reference.

TECHNICAL FIELD

The present invention relates to a manufacturing machine for the production of disposable cartridges for electronic cigarettes .

PRIOR ART

Recently, disposable (i.e. single use) cartridges have been proposed for electronic cigarettes comprising a casing made of a plastic material having a tubular shape with a micro-perforated bottom wall and a quantity of tobacco powder, overlapped by a pad made of filtering material, is contained therein; the casing is closed at an upper end (i.e. opposite the micro-perforated bottom wall) by means of a sealing ring which is welded to the casing itself.

The production of said cartridges provides for filling each casing with a calibrated quantity of tobacco powder, slightly compressing the quantity of tobacco powder inside the casing so as to obtain the desired density and then capping the casing by applying both the filtering pad and the sealing ring to the open upper end. The cartridges are subsequently individually weighed in order to allow discarding of non-compliant ones that hold an insufficient or excessive amount of powdered tobacco on the inside thereof.

Once the production of the cartridges is finished, the latter are inserted into sealed packages, typically blister packages.

Patent applications WO2017051348A1, W02017051349A1 and WO2017051350A1 provide an example of a manufacturing machine for the production of disposable cartridges for electronic cigarettes of the type described above. This manufacturing machine is able to operate efficiently (i.e. with a high hourly production rate, in terms of the number of cartridges produced in the time unit) and effectively (i.e. with a small number of discarded pieces and with a high final quality) ; however, electronic cigarettes which use the above described cartridge are experiencing considerable market success and therefore the manufacturers of the above-described cartridges require a manufacturing machine with a further increased performance, i.e. with a greater hourly production rate, with respect to the known manufacturing machine described in the patent applications WO2017051348A1, W02017051349A1 and WO2017051350A1.

DESCRIPTION OF THE INVENTION

The object of the present invention is to provide a manufacturing machine for the production of disposable cartridges for electronic cigarettes, the which filling unit allows to achieve high productivity while ensuring high quality standards and, at the same time, being easy and inexpensive to produce.

According to the present invention, a manufacturing machine is provided for the production of disposable cartridges for electronic cigarettes, as claimed in the appended claims.

The claims describe preferred embodiments of the present invention forming an integral part of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described with reference to the attached drawings, which illustrate some non-limiting embodiments thereof, wherein:

• Figure 1 is a longitudinal section view of a cartridge for electronic cigarette;

• Figure 2 is a perspective view of a manufacturing machine which produces the cartridge for electronic cigarette of

Figure 1;

• Figure 3 is a perspective view of the manufacturing machine of Figure 2 with the removal of some parts for clarity;

• Figure 4 is a schematic plan view of the manufacturing machine of Figure 2;

• Figure 5 is a schematic longitudinal section view of part of a first manufacturing drum of the manufacturing machine of Figure 2;

• Figure 6 is a schematic longitudinal section view of part of a second manufacturing drum of the manufacturing machine of

Figure 2;

• Figure 7 is a schematic plan view of a feeding unit of the manufacturing machine of Figure 2;

• Figures 8 and 9 are two enlarged-scale views of some fingers of the feeding unit of the tubular casings of Figure 7 in an expanded configuration and in a compressed configuration, respectively;

• Figures 10 and 11 are two schematic longitudinal section views of part of the feeding unit of Figure 7 at an insertion station and at two different operating times;

• Figure 12 is a schematic longitudinal section view of part of the feeding unit of Figure 7 at an insertion station;

• Figure 13 is a schematic plan view of a filling unit of the manufacturing machine of Figure 2;

· Figure 14 is a schematic longitudinal section view of part of the filling unit of Figure 13;

• Figure 15 is a perspective view and with the removal of parts for clarity of a feeding unit of pads of filtering material of the manufacturing machine of Figure 2;

· Figures 16 and 17 are two schematic side views of the feeding unit of Figure 15 at two different operating times; • Figure 18 is a schematic front view of a hopper and of a cutting device of the feeding unit of Figure 15;

• Figure 19 is a schematic and partially longitudinal section view of a tray of the feeding unit of Figure 15;

· Figure 20 is a schematic plan view of a pusher and of a corresponding supply channel of the feeding unit of Figure 15;

• Figure 21 is a schematic and longitudinal section view of a transfer unit of the manufacturing machine of Figure 2;

• Figure 22 is a schematic plan view of a feeding unit of the sealing rings of the manufacturing machine of Figure 2;

• Figure 23 is a schematic longitudinal section view of part of the feeding unit of Figure 22 at an insertion station;

• Figure 24 is a schematic longitudinal section view of part of the feeding unit of Figure 22 at a feeding station;

· Figure 25 is a schematic longitudinal section view of a welding unit of the manufacturing machine of Figure 2;

• Figure 26 is a schematic longitudinal section view of an output unit of the manufacturing machine of Figure 2;

• Figure 27 is a schematic and plan view of a control station of the manufacturing machine of Figure 2;

• Figures 28 and 29 are two schematic longitudinal section views of an alternative of the feeding unit of Figure 7 at an insertion station and at two different operating times;

• Figure 30 is a schematic plan view of a centring device of the feeding unit of Figures 28 and 29;

• Figures 31 and 32 are two schematic longitudinal section views of an alternative of the feeding unit of Figure 22 at an insertion station and at two different operating times;

• Figure 33 is a schematic longitudinal section view of a further alternative of the feeding unit of Figure 22 at an insertion station;

• Figure 34 is a schematic longitudinal section view of part of a second manufacturing drum in an alternative of the manufacturing machine of Figure 2; and

· Figures 35 and 36 are two schematic top views of a seat of the second manufacturing drum of Figure 34 with a pair of jaws arranged respectively in a holding position and in a transfer position .

PREFERRED EMBODIMENTS OF THE INVENTION

In Figure 1, the number 1 denotes as a whole a disposable cartridge for electronic cigarettes. The disposable cartridge 1 comprises a tubular casing 2 made of plastic material having a micro-perforated bottom wall 3 and a side wall 4 having a substantially cylindrical shape; a quantity 5 of powdered tobacco is contained inside the tubular casing 2 (in contact with the bottom wall 3) overlapped by a pad 6 of filtering material. Finally, the disposable cartridge 1 comprises a sealing ring 7 (i.e. a sealing washer 7) which is inserted around an upper end (otherwise completely open) of the tubular casing 2 so as to prevent the pad 6 of filtering material from escaping; preferably, the sealing ring 7 is welded to the tubular casing 2. According to a preferred but non-binding embodiment illustrated in the accompanying figures, the tubular casing 2 has a bulge (i.e. a transversely larger portion) near the upper end (i.e. of the end opposite the bottom wall 3 and near the sealing ring 7) ; this bulge determines the presence of an undercut near the upper end.

In Figures 2 and 3, number 8 denotes as a whole a manufacturing machine for the production of the disposable cartridges 1 described above. The manufacturing machine 8 performs an intermittent movement, i.e. its conveyors cyclically alternate motion steps and stop steps.

As illustrated in Figure 4, the manufacturing machine 8 comprises a manufacturing drum 9 which is arranged horizontally and is mounted rotating in a stepwise manner around a vertical rotation axis 10; in other words, the manufacturing drum 9 is set into rotation with an intermittent motion, i.e. a non-continuous motion which provides a cyclical alternation of motion steps, wherein the manufacturing drum 9 is moving, and of still steps, wherein the manufacturing drum 9 stops. The manufacturing drum 9 supports twelve groups 11 of seats 12, each adapted to receive and contain a corresponding tubular casing 2; in particular, each group 11 comprises forty-two seats 12 aligned along three straight lines, which are parallel to one another (each of the three straight lines has fourteen seats 12) and the twelve groups 11 are arranged to define, in plan, a regular polygon (i.e. a dodecahedron) on the surface of the manufacturing drum 9.

The manufacturing machine 8 comprises a further manufacturing drum 13 which is arranged horizontally beside the manufacturing drum 9 and is mounted rotating in a stepwise manner around a vertical rotation axis 14 parallel to the rotation axis 10; in other words, the manufacturing drum 13 is set into rotation with an intermittent motion, i.e. a non-continuous motion which provides a cyclical alternation of motion steps, wherein the manufacturing drum 13 is moving, and still steps, wherein the manufacturing drum 13 stops. The manufacturing drum 13 supports twelve groups 15 of seats 16, each adapted to receive and contain a corresponding tubular casing 2; in particular, each group 15 comprises forty-two seats 16 aligned along three straight lines, which are parallel to one another (each of the three straight lines has fourteen seats 16) and the twelve groups 15 are arranged to define, in plan, a regular polygon (i.e. a dodecahedron) on the surface of the manufacturing drum 13.

The manufacturing machine 8 comprises a feeding station SI, in which a feeding unit 17 inserts a corresponding empty tubular casing 2 in each seat 12 of a group 11, that is standing still; in particular, the feeding unit 17 simultaneously inserts forty-two empty tubular casings 2 in as many seats 12 of a group 11 that is standing still in the feeding station SI. Downstream of the feeding station SI, relative to the rotation direction of the manufacturing drum 9, three filling stations S2 are arranged in succession in each of which a filling unit 18 is arranged, which feeds into each tubular casing 2 carried by a seat 12 of a group 11, standing still, a corresponding quantity 5 of tobacco; in particular, each filling unit 18 simultaneously feeds fourteen quantities 5 of tobacco into as many seats 12 of a group 11 that is standing still in the feeding station S2. The filling unit 18 of the first feeding station S2 feeds fourteen quantities 5 of tobacco into as many seats 12 of the innermost row of the group 11 that is standing still in the first feeding station S2, the filling unit 18 of the second feeding station S2 feeds fourteen quantities 5 of tobacco into as many seats 12 of the intermediate row of the group 11 that is standing still in the second feeding station S2, and the filling unit 18 of the third feeding station S2 feeds fourteen quantities 5 of tobacco into as many seats 12 of the outermost row of the group 11 that is standing still in the third feeding station S2.

Downstream of the filling stations S2 (i.e. downstream of the last filling station S2), relative to the rotation direction of the manufacturing drum 9, a feeding station S3 is arranged, in which a feeding unit 19 feeds a corresponding pad 6 of filtering material into each tubular casing 2 carried by a seat 12 of a group 11, standing still; in particular, the filling unit 19 simultaneously feeds forty-two pads 6 of filtering material into as many seats 12 of a group 11 that is standing still in the feeding station S3.

Downstream of the feeding station S3, relative to the rotation direction of the manufacturing drum 9, a transfer station S4 is arranged, in which a transfer unit 20 transfers the tubular casings 2 (each containing a quantity 5 of tobacco and a pad 6 of filtering material) from the seats 12 of a group 11 of the manufacturing drum 9 to the seats 16 of a group 15 of the manufacturing drum 13; in particular, the transfer unit 20 simultaneously transfers forty-two tubular casings 2 from as many seats 12 of a group 11 that is standing still in the transfer station S4 to as many seats 16 of a group 15 that is standing still in the transfer station S4. In the transfer station S4, the two manufacturing drums 9 and 13 are partially overlapped so that the seats 12 of a group 11 of the manufacturing drum 9 are vertically aligned with the seats 16 of a group 15 of the manufacturing drum 13; consequently, in the transfer station S4 the transfer of the tubular casings 2 takes place by means of a linear and vertical movement (i.e. a rise of the casings 2 if the manufacturing drum 9 is arranged below the manufacturing drum 13 or a lowering of the casings 2 if the manufacturing drum 9 is arranged above the manufacturing drum 13) .

Downstream of the insertion station S4, relative to the rotation direction of the manufacturing drum 13, a feeding station S5 is arranged, in which a feeding unit 21 feeds a corresponding sealing ring 7 into each tubular casing 2 carried by a seat 16 of a group 15, standing still; in particular, the filling unit 21 simultaneously feeds forty-two sealing rings 7 into as many seats 16 of a group 15 that is standing still in the feeding station S5. Downstream of the feeding station S5, relative to the rotation direction of the manufacturing drum 13, three welding stations S6 are arranged in succession, in each of which a welding unit 22 performs (preferably by ultrasonic welding) the welding of each sealing ring 7 to the corresponding tubular casing 2 carried by a seat 16 of a group 15 that is standing still; in particular, each welding unit 22 simultaneously welds fourteen sealing rings 7 to as many tubular casings 2 carried by the seats 16 of a group 15 that is standing still in the welding station S6. The welding unit 22 of the first welding station S6 welds fourteen sealing rings 7 in as many seats 16 of the intermediate row of the group 15 that is standing still in the first welding station S6, the welding unit 22 of the second welding station S6 welds fourteen sealing rings 7 in as many seats 16 of the outermost row of the group 15 that is standing still in the second welding station S6, and the welding unit 22 of the third welding station S6 welds fourteen sealing rings 7 in as many seats 16 of the innermost row of the group 15 that is standing still in the third welding station S6.

In the welding stations S6, the manufacturing of the disposable cartridges 1 is completed, i.e. downstream of the welding stations S6 the disposable cartridges 1 are finished and ready for use. Downstream of the welding stations S6 (i.e. downstream of the last welding station S6) , relative to the rotation direction of the manufacturing drum 13, an output station S7 is arranged, in which an extraction unit 23 pulls a corresponding disposable cartridge 1 out from each seat 16 of a group 15 that is standing still; in particular, the extraction unit 23 simultaneously extracts forty-two disposable cartridges 1 from as many seats 16 of a group 15 that is standing still in the output station S7.

From the foregoing it is clear that all the steps of the production process of the disposable cartridges 1 (such as for example the filling of the quantities 5 of tobacco, the feeding of the pads 6 of filtering material, the feeding of the sealing rings 7, the welding of the sealing rings 7) contained in the seats 12/16 of a same group 11/15 are carried out in parallel, i.e. they are carried out simultaneously for a plurality (fourteen or forty-two) of disposable cartridges 1 contained in the seats 12/16 of a same group 11/15.

As illustrated in Figure 5, each seat 12 of the manufacturing drum 13 comprises a through housing channel 24 which passes through the manufacturing drum 9 from side to side and is adapted to contain a tubular casing 2; in particular, each housing channel 24 is transversely wider than a tubular casing 2 so as to allow the tubular casing 2 to pass through the inside of the housing channel 24 (as will be described in the following, each tubular casing 2 enters from the bottom into the corresponding housing channel 24 in the feeding station SI and exits from the top of the corresponding housing channel 24 in the transfer station S4) . Each seat 12 of the manufacturing drum 13 further comprises a pair of opposite jaws 25, which are fitted in the housing channel 24 and are movable between a holding position (illustrated in the two seats 12 on the right in Figure 5) in which they engage a tubular casing 2 arranged in the housing channel 24 (thus preventing the descent of the tubular casing 2 through the housing channel 24) and a transfer position (illustrated in the seat 12 to the left in Figure 5) in which they do not engage a tubular casing 2 arranged in the housing channel 24 (thus allowing the free sliding of the tubular casing 2 along the housing channel 24) . According to a preferred embodiment, the opposite jaws 25 are arranged immediately below the undercut formed by the transverse bulge of the upper part of the tubular casing 2 so that said undercut rests on the jaws 25 when the jaws 25 are arranged in the holding position (illustrated in the two seats 12 on the right in Figure 5) . In the embodiment illustrated in the accompanying figures, the axial length of each housing channel 24 is (slightly) greater than the axial length of the tubular casings 2 and therefore the tubular casings 2 are completely contained (without any protrusion) in the housing channels 24; according to other perfectly equivalent embodiments not illustrated, the axial length of each housing channel 24 is greater than the axial length of the tubular casings 2 or the axial length of each housing channel 24 is (slightly or much) smaller than the axial length of the tubular casings 2 (in this last case the tubular casings 2 are not completely contained in the housing channels 24 and therefore protrude from the top and/or from the bottom of the housing channels 24) .

In the embodiment illustrated in the accompanying figures, the two jaws 25 of each seat 12 have a limited axial extension, i.e. they are (much) shorter than the housing channel 24; in other words, in the embodiment illustrated in the accompanying figures, the two jaws 25 of each seat 12 engage a limited portion of the housing channel 24 which has fixed walls above and below the jaws 25. According to a perfectly equivalent alternative embodiment not illustrated, the two jaws 25 of each seat 12 have a greater axial extension which can also coincide with the axial extension of the inside of the housing channel 24; in other words, the housing channel 24 may have fixed walls only above the two jaws 25, the housing channel 24 may have fixed walls only under the two jaws 25, or the housing channel 24 may not have fixed walls neither above nor below the two jaws 25 (i.e. the housing channel 24 may not have fixed walls, but only two jaws 25) .

As illustrated in Figure 6, each seat 16 of the manufacturing drum 13 comprises a through housing channel 26 which passes through the manufacturing drum 13 from side to side and is adapted to contain a tubular casing 2; in particular, each housing channel 26 is transversely wider than a tubular casing 2 so as to allow the tubular casing 2 to pass through the inside of the housing channel 26 (as will be described in the following, each tubular casing 2 enters from the bottom into the corresponding housing channel 26 in the feeding station SI and always exits from the bottom of the corresponding housing channel 26 in the transfer station S4) . Each seat 16 of the manufacturing drum 13 comprises, furthermore, a pair of opposite jaws 27, which are fitted in the housing channel 26 and are movable between a holding position (illustrated in the two seats 16 on the right in Figure 6) in which they engage a tubular casing 2 arranged in the housing channel 26 (thus preventing the descent of the tubular casing 2 through the housing channel 26) and a transfer position (illustrated in the seat 16 to the left in Figure 6) in which they do not engage a tubular casing 2 arranged in the housing channel 26 (thus allowing the free sliding of the tubular casing 2 along the housing channel 26) . According to a preferred embodiment, the opposite jaws 27 are arranged immediately below the undercut formed by the transverse bulge of the upper part of the tubular casing 2 so that said undercut rests on the jaws 27 when the jaws 27 are arranged in the holding position (illustrated in the two seats 16 on the right in Figure 6) . In the preferred embodiment illustrated in the accompanying figures, the axial length of each housing channel 26 is (slightly) smaller than the axial length of the tubular casings 2 and therefore the tubular casings 2 protrude (slightly) both from above, and below the housing channels 26; according to other perfectly equivalent embodiments not illustrated, the axial length of each housing channel 24 is (much or slightly) greater than the axial length of the tubular casings 2 (therefore the tubular casings 2 are completely contained, without any protrusion, in the housing channels 24) or the axial length of each housing channel 24 is greatly smaller the axial length of the tubular casings 2 (in this latter case the tubular casings 2 widely extend both from above and below the housing channels 26) .

In the embodiment illustrated in the accompanying figures, the two jaws 27 of each seat 16 have a limited axial extension, i.e. they are (much) shorter than the housing channel 26; in other words, in the embodiment illustrated in the attached figures, the two jaws 27 of each seat 16 engage a limited portion of the housing channel 26 which has fixed walls above and below the jaws 27. According to a perfectly equivalent alternative embodiment not illustrated, the two jaws 27 of each seat 16 have a greater axial extension which can also coincide with the axial extension of the inside of the housing channel 26; in other words, the housing channel 26 may have fixed walls only above the two jaws 27, the housing channel 26 may have fixed walls only under the two jaws 27, or the housing channel 26 may not have fixed walls neither above nor below the two jaws 27 (i.e. the housing channel 26 may not have fixed walls, but only two jaws 27) .

The feeding unit 17 feeds the tubular casings 2 to the seats 12 of a group 11 of seats 12 that is standing still at the feeding unit 17 (i.e. that is standing still in the feeding station SI) . As illustrated in Figure 7, the feeding unit 17 comprises a feeding drum 28 (with a parallelepiped shape) which is mounted rotating in a stepwise manner around a vertical rotation axis 29 parallel to the rotation axis 10 of the manufacturing drum 9; the feeding drum 28 supports two groups 30 of opposite fingers 31 (i.e. the two groups 30 are arranged on opposite sides of the rotation axis 28) . Each group 30 comprises fourteen fingers 31 which are parallel and side-by-side one another and each finger 31 has three seats 32 each adapted to receive a corresponding tubular casing 2 (as better illustrated in Figures 8 and 9) ; It is important to note that the number of seats 32 of each finger 31 is equal to the number of lines of each group 11 of seats 12 of the manufacturing drum 9. As illustrated in Figures 10, 11 and 12, each second seat 32 is formed by a blind hole (obtained inside the corresponding finger 31) having a bottom wall on which a corresponding tubular casing 2 rests.

As illustrated in Figure 7, each group 30 of fingers 31 is adapted to receive corresponding tubular casings 2 (in particular forty-two tubular casings 2) in an insertion station S8 and is adapted to release the tubular casings 2 (in particular forty-two tubular casings 2) to the group 11 of seats 12 of the manufacturing drum 9 that is standing still in the feeding station SI. Furthermore, each finger 31 is mounted on the feeding drum 28 so as to translate relative to the feeding drum 28 along a separating direction Dl perpendicular to the rotation axis 29 so as to move away from or closer to the adjacent fingers 31. The feeding drum 28 is provided with an actuator device 33 which translates the fingers 31 along the separating direction Dl so as to arrange the fingers 31 at a first mutual distance in the insertion station S8 and at a second mutual distance, which is different from the first mutual distance, in the feeding station SI; in the embodiment illustrated in the accompanying figures, the second mutual distance is greater than the first mutual distance.

In the embodiment illustrated in the accompanying figures, the fingers 31 of each group 30 move relative to the others by means of a translation along the separating direction Dl; according to a different and perfectly equivalent embodiment not illustrated, the fingers 31 of each group 30 move relative to one another by means of a roto-translation or by means of a rotation which has a component along the separating direction Dl.

The function of the actuator device 33 is to modify the pitch (i.e. the mutual distance) between the tubular casings 2 which, in the embodiment illustrated in the accompanying figures, have a 9.5 mm pitch in the insertion station S8 and have a 12 mm pitch in the feeding station SI. The increase in the pitch (i.e. the mutual distance) between the tubular casings 2 is clearly visible in Figures 8 and 9 showing the fingers 31 (carrying the seats 32) in the feeding station SI (Figure 9, pitch equal to 12 mm) and in the insertion station S8 (Figure 8, pitch equal to 9.5 mm) . According to a preferred embodiment, the actuator device 33 is passive (i.e. it has no sources which autonomously generate a movement) and uses cams which move the fingers 31 by using the rotation movement of the feeding drum 28 around the rotation axis 29; according to a preferred, but not binding, embodiment, the cam actuator device 33 is of the desmodromic type devoid of elastic elements, i.e. the translation movement of the fingers 31 is always imparted by cams which move the fingers 31 in both directions without using elastic thrust.

It is important to note that, according to different embodiments equivalent to one another, the actuator device 33 can translate the fingers 31 of each group 30 into the feeding station SI (when the feeding drum 28 is standing still), in the insertion station S8 (when the feeding drum 28 is standing still) or in the path between the feeding station SI and the insertion station S8 (when the feeding drum 28 is moving) . Obviously, if the actuator device 33 comprises a motor (typically electric) , then the actuator device 33 is able to translate the fingers 31 of each group 30 even when the feeding drum 28 is standing still; on the other hand, if the actuator device 33 comprises cams which exploit the rotary movement of the feeding drum 28, then the actuator device 33 is able to translate the fingers 31 of each group 30 only when the feeding drum 28 is moving.

As illustrated in Figure 7, the feeding unit 17 comprises three conveying channels 34 which are inclined downwards (but may also be horizontal) and feed three respective rows of tubular casings 2 towards the insertion station S8; as is evident in Figure 7, in the feeding station S8 each conveying channel 34 is coupled (aligned) to a corresponding seat 32 in each finger 31. As better illustrated in Figures 10 and 11, each conveying channel 34 is laterally delimited by corresponding sides 35 (which can be doubled as illustrated in the attached figures, single, or triple) and is delimited, at the bottom, by a support plane 36. The conveying channels 34 can feed the respective rows of tubular casings 2 solely by gravity (by exploiting the downward inclination) or by adding compressed air blowers (blower air conveyor) or vibrations (vibrating conveyor) ; alternatively, other configurations of the conveying channels 34 are also possible with the only constraint that the conveying channels 34 feed the respective rows of tubular casings 2 towards the insertion station S8.

As illustrated in Figure 7, the feeding unit 17 also comprises an accompanying element 37 which has three parallel prongs, each of which is coupled to a corresponding conveying channel 34; in particular, the accompanying element 37 is movable within the conveying channels 34 and parallel to the conveying channels 34 to accompany the progressive descent of the tubular casings 2 inside the insertion station S8. Moreover, the feeding unit 17 comprises a gate 38 which is coupled to the conveying channels 34, is arranged immediately upstream of the insertion station S8 (i.e. delimits the beginning of the insertion station S8) and is movable between an opening position, in which it allows the tubular casings 2 to enter into the insertion station S8 and a closing position which prevents the tubular casings 2 from entering the insertion station S8.

In use, when the insertion station S8 is full (i.e. when in the insertion station S8 there are forty-two tubular casings 2 arranged in three rows of fourteen tubular casings 2 in the three conveying channels 34 as illustrated in Figure 7), the gate 38 is closed (i.e. it is arranged in the closing position) so as to "isolate" the sections of the conveying channels 34 comprised in the insertion station S8 from the remaining sections of the conveying channels 34 and then the forty two tubular casings 2 in the insertion station S8 are transferred (with the methods described in the following) from the conveying channels 34 to the seats 32 of the fingers 31 of a group 30 that is standing still in the insertion station S8. When the forty-two tubular casings present in the insertion station S8 have been transferred from the conveying channels 34 to the seats 32 of the fingers 31 of a group 30 that is standing still in the insertion station S8, the insertion station S8 is empty (i.e. completely devoid of tubular casings 2) ; at this point, the prongs of the accompanying device 37 are fed along the conveying channels 34 until reaching the gate 38 and therefore the gate 38 is opened (i.e. is arranged in the opening position) so as to allow the tubular casings 2 to enter the insertion station S8 again, sliding by gravity along the three conveying channels 34; the descent of the tubular casings 2 along the three conveying channels 34 and in the insertion station S8 is not free (i.e. uncontrolled) but is controlled by the three prongs of the accompanying element 37 which rest on the corresponding first three tubular casings 2 to accompany at controlled and predetermined speed the descent of the first three tubular casings 2 (followed by the other tubular casings 2) along the three conveying channels 34. Due to the action of the accompanying element 37, the tubular casings 2 are never "abandoned" and therefore have no possibility of "tilting" inside the conveying channels 34.

According to a preferred embodiment, the gate 38 comprises, for each conveying channel 34, a corresponding wedge-shaped stop element which is inserted (in the closing position) between two successive tubular casings 2 to prevent further advancement of the tubular casing 2 arranged upstream along the conveying channel 34.

According to a possible embodiment illustrated in Figure 22, a video camera T is provided which frames the three conveying channels 91 at the gate 95 so as to detect the exact position of the sealing rings 7 inside the three conveying channels 91; in this way, the movement of gate 95 (particularly the movement from the opening position to the closing position) is synchronized with the exact position of the sealing rings 7 inside the three conveying channels 91 in order to avoid errors in the maneuvering of the gate 95. In other words, the movement of the gate 95 is controlled according to the exact position of the sealing rings 7 inside each conveying channel 91 detected by the video camera T. In this regard it is important to note that the sealing rings 7 ( unlike the tubular casings 2) are elastically deformable and therefore, due to possible elastic deformation, the position of the sealing rings 7 inside the three conveying channels 91 can be (slightly) variable in a substantially unpredictable way; said unpredictability is detected and compensated by means of the video camera T which is able to accurately determine the effective position of the sealing rings 7 inside the three conveying channels 91.

As illustrated in Figures 10 and 11, in the insertion station S8 the seats 32 of the fingers 31 are aligned with the corresponding conveying channels 34 and are arranged below the corresponding conveying channels 34 so that each tubular casing 2 carried by a conveying channel 34 is vertically aligned with a corresponding seat 32 of the fingers 31. As previously said, the conveying channels 34 comprise a support plane 36 on which the tubular casings 2 rest. In the insertion station S8, the support plane 36 has a plurality of through holes 39, each adapted to allow the passage of a tubular casing 2; moreover, the support plane 36, at least in the insertion station S8, is movable (under the thrust of an actuator device 40) between a filling position (illustrated in Figure 10) in which the through holes 39 are not aligned with respect to the corresponding conveying channels 34 so as to prevent the passage of the tubular casings 2 through the through holes 39 (i.e. so as to misalign the through holes 39 relative to the tubular casings 2 contained in the conveying channels 34) and a transfer position (illustrated in Figure 11) in which the through holes 39 are aligned with the corresponding conveying channels 34 so as to allow the passage of the tubular casings 2 through the through holes 39 (i.e. to align the through holes 39 relative to the tubular casings 2 contained in the conveying channels 34) . In particular, the actuator device 40 moves the support plane 36 between the filling position (illustrated in Figure 10) and the transfer position (illustrated in Figure 11) by translating the support plane 36 along a control direction D2 which is perpendicular to the separating direction Dl, is perpendicular to the rotation axis 29, and is perpendicular to the conveying channels 34. According to a possible embodiment, the through holes 39 are not separated from one another, and, together form a single slot (i.e. a single large through hole 39 which has an elongated shape) .

As illustrated in Figures 10 and 11, the feeding unit 17 comprises a group (forty-two) of pushers 41 which are arranged in the insertion station S8 and are movable in a vertical manner for pushing the tubular casings 2 from the conveying channel 34 to the seats 32 of the fingers 31 of a group 30 that is standing still in the insertion station S8; furthermore, the feeding unit 17 comprises a group (forty-two) of accompanying elements 42 which are opposite to the pushers 41 and are movable in a vertical manner so as to be inserted into the seats 32 of the fingers 31 of a group 30 that is standing still in the insertion station S8 and accompany the descent of the tubular casings 2 from the conveying channel 34 to the seats 32 of the fingers 31. Each seat 32 of the fingers 31 has a through hole 43 (small enough to prevent the entry of a tubular casing 2) through which an accompanying element 42 can enter from the bottom into the seat 32.

In other words, in the insertion station S8, each tubular casing 2 is transferred by a conveying channel 34 (passing through a through hole 39 of the support plane 36) to the underlying seat 32 of a finger 31 of a group 30 that is standing still in the insertion station S8 thus performing a vertical downwards movement during which the tubular casing 2 is engaged, at the top, by a pusher 41 and at the bottom by an accompanying device 42 (i.e. being "pinched" between a pusher 41 arranged at the top and by an accompanying element 42 arranged at the bottom) . In this regard, it is important to note that pushers 41 and the accompanying elements 42 would not be strictly necessary, since the vertical downwards movement would in any case be imparted on the tubular casings 2 by the force of gravity; however, the presence of the pushers 41 and of the accompanying elements 42 allows to impart a controlled movement to the tubular casings 2 which prevents any incorrect positioning or bouncing of the tubular casings 2.

As illustrated in Figure 12, the seats 32 of the fingers 31 of a group 30 that is standing still in the feeding station SI are aligned with the corresponding seats 12 of a group 11 that is standing still in the feeding station SI so that each tubular casing 2 carried by a seat 32 of the fingers 31 is vertically aligned with a corresponding seat 12 of the manufacturing drum 9. As illustrated in Figure 12, the feeding unit 17 comprises a group of (forty-two) pushers 44 which are arranged in the feeding station SI and are movable in a vertical manner to be inserted (through the through holes 43) inside the seats 32 of the fingers 31 of a group 30 that is standing still in the feeding station SI thus pushing the tubular casings 2 from the seats 32 of the fingers 31 to the seats 12 of a group 11 that is standing still in the feeding station SI; moreover, the feeding unit 17 comprises a group of (forty-two) accompanying elements 45 which are opposite to the pushers 44 and are movable in a vertical manner to accompany the ascent of the tubular casings 2 from the seats 32 of the fingers 31 to the seats 12 of the manufacturing drum 9. As previously stated, each seat 32 of the fingers 31 has a through hole 43 (small enough to prevent the entry of a tubular casing 2) in the lower part, through which a pusher 44 can enter from the bottom into the seat 32.

In other words, in the feeding station SI each tubular casing 2 is transferred from a seat 32 of a finger 31 of a group 30 that is standing still in the feeding station SI to the overlying seat 12 of a group 11 that is standing still in the feeding station SI by performing a vertical upwards movement during which the tubular casing 2 is engaged at the bottom by a pusher 44 and, at the top, by an accompanying element 45 (i.e. being "pinched" between a pusher 44 arranged at the bottom and by an accompanying element 45 arranged at the top) . In this regard it is important to note that accompanying elements 45 would not be strictly necessary; however, the presence of the accompanying elements 45 allows to impart a controlled movement to the tubular casings 2 which prevents any incorrect positioning or bouncing of the tubular casings 2.

As previously stated, each seat 12 of the manufacturing drum 9 comprises a through housing channel 24 which passes through the manufacturing drum 9 from side to side and is adapted to contain a tubular casing 2 and a pair of opposite jaws 25, which are fitted into the housing channel 24 and are movable between a holding position, in which they engage a tubular casing 2 arranged in the housing channel 24 and a transfer position, in which they do not engage a tubular casing 2 arranged in the housing channel 24. During the entering of a tubular casing 2 into a corresponding seat 12 of the manufacturing drum 9, the two jaws 25 are kept in the transfer position and then, only when the entering of tubular casing 2 into the seat 12 has been completed, then the two jaws 25 are brought into the holding position.

Each filling unit 18 is similar, in its general structure, to the filling unit described and illustrated in the patent applications WO2017051348A1, W02017051349A1 and W02017051350A1 to which refer for a more detailed description of the filling unit 18.

As illustrated in Figure 13, each filling unit 18 comprises a cylindrical-shaped tank 46 which is arranged horizontally and is mounted rotating in a stepwise manner around a vertical rotation axis 47 parallel to the rotation axis 10; in other words, the tank 46 is set into rotation with an intermittent motion, i.e. a non-continuous motion which provides a cyclical alternation of steps of motion, wherein the tank 46 is moving, and still steps, wherein the tank 46 stops. Each tank 46 is arranged beside the manufacturing drum 9 and partially overlapping the manufacturing drum 9 at the filling station S2; in particular, the tank 46 is arranged higher than the manufacturing drum 9 so as to be on top of the manufacturing drum 9 at the filling station S2 (as illustrated in Figure 14) . Each tank 46 supports six groups 48 of seats 49, each adapted to receive and contain a corresponding quantity 5 of tobacco; in particular, each group 48 comprises fourteen seats 49 aligned along a straight line and the six groups 48 are arranged to define, in plan, a regular polygon (i.e. a hexagon) on the surface of the annular tank 46.

Each tank 46 is delimited, at the bottom, by a circular shaped base disc 50 and is delimited, on the sides, by a cylindrical side wall 51 which projects perpendicular from the base disc 50; the seats 49 are obtained in the base disc 50, i.e. they are (partially) formed by circular through holes made through the base disc 50. Centrally, from the base disc 50, a cylindrical central element 52 rises, which gives an annular shape (i.e. a "donut" shape) to the inner volume of the tank 46.

Each tank 46 is coupled to a cylindrical feeding duct 53 which is orientated in a vertical manner (at least in its end portion) and has an outlet opening arranged inside the tank 46; the feeding duct 53 continuously feeds inside the tank 46 a flow of tobacco which forms a bed resting on the base disc 50 of the tank 46.

Each filling unit 18 comprises a transfer device 54 which is arranged in a fixed position (i.e. without rotating together with the tank 46) at the filling station S2 and cyclically transfers the quantities 5 of tobacco contained in the seats 49 of a group 48 that is standing still in the filling station S2 into corresponding seats 12 of a group 11 that is standing still in the filling station S2 the manufacturing drum 9. As illustrated in Figure 14, in each filling station S2, the tank 46 (i.e. the base disc 50 of the tank 46) is partially overlapping the manufacturing drum 9 so that the seats 49 of a group 48 of the tank 46 are vertically aligned and arranged above the seats 12 of a group 11 of the manufacturing drum 9; consequently, in each filling station S2 the transfer of the quantities 5 of tobacco takes place by means of a linear and vertical downward movement (i.e. a descent of the quantities 5 of tobacco) . Each transfer device 54 comprises a plurality of pushers 55, each coupled to a corresponding seat 49 of a group 48 that is standing still in the filling station S2 and is provided with an alternating vertical motion for pushing the quantity 5 of tobacco contained in the corresponding seat 49 downwards, i.e. towards a corresponding tubular casing 2 that is standing still.

As illustrated in Figure 14, below the base disc 50, a further intermediate disc 56 is arranged, which is interposed between the base disc 50 and the manufacturing drum 9 (i.e. between the seats 49 containing the quantities 5 of tobacco and the seats 12 containing the tubular casings 2) ; through the intermediate disc 56 groups of through holes are formed, which are internally lined by means of respective feeding ducts 57 which protrude downwardly towards the outside of the intermediate disc 56 itself. In use, each tubular casing 2, which is housed in a seat 12 of the manufacturing drum 9 and that is standing still in the corresponding filling station S2, is pushed upwards (i.e. towards the intermediate disc 56) by a pusher 58 so as to bring its upper open end in contact with the mouth of the respective feeding duct 57. According to a possible embodiment, the outlet mouth of each feeding duct 57 can be funnel-shaped (i.e. a truncated-conical shape) . According to a possible embodiment, the outlet mouth of each feeding duct 57 can be inserted partially inside the open upper end of a corresponding tubular casing 2 when the tubular casing 2 itself is pushed upward (i.e. towards the intermediate disc 56) by the corresponding pusher 58.

According to a preferred embodiment illustrated in Figure 14, each seat 49 has a variable axial size (therefore a variable volume) due to a telescopic mechanism: each seat 49 is formed by a through hole made through the base disc 50 which is lined by means of a tubular liner 59 and by a further tubular liner 60 which is partially arranged around the tubular liner 59 and can slide relative to the tubular liner 59 itself. In use, the tubular liners 60 (together with the underlying intermediate disc 56) can axially slide so as to vary the overall volume of the seats 49.

Immediately below each group 48 of seats 49 a shutter element 61 is arranged, which is provided, for each seat 49, with a plug 62 which is permeable to air (but not to tobacco) and a through hole 63 arranged beside the plug 62. Each shutter element 61 is movably mounted so as to radially move, under the thrust of an actuator device 64, between a closing position (illustrated in Figure 14) in which a corresponding plug 62 is arranged below each seat 49 for closing the bottom of the seat 49 itself and prevent the descent of the tobacco and an opening position, in which a corresponding through hole 63 is arranged below each seat 49 so as so as to allow the descent of the tobacco. In use, the actuator device 64 keeps each shutter element 61 in the closing position (illustrated in Figure 14) outside of the filling station S2 and moves the shutter element 61 to the opening position inside the filling station S2 so as to allow the descent of the quantity 5 of tobacco from the seat 49 towards a corresponding tubular casing 2 carried by a seat 12 of the manufacturing drum 9.

In the illustrated embodiment, each plug 62 is permeable to air (but not to tobacco) so as to allow a bottom suction to be applied to the seats 49, which tends to favour the entering of the tobacco into the seats 49; in particular, each plug 62 is permeable to air due to the presence of a plurality of through holes of a size smaller than the size of the tobacco fibres so that air can pass through said through holes but not the tobacco. In use, during the formation of the quantities 5 of tobacco (i.e. on the outside of the filling station S2) a suction source is connected to the feeding ducts 57, so as to generate a depression inside the feeding ducts 57 that, through the plugs 62 which are permeable to air, is also provided inside the seats 49, thus favouring the entering of the tobacco into the seats 49.

According to a different embodiment, not illustrated, each plug 62 is completely sealed (i.e. it is not permeable to air or to tobacco) .

According to a preferred embodiment, the actuator device 64 controls the sliding of the shutter elements 61 (there is a shutter element 61 for each group 48 of seats 49) independently of the rotation of the tank 46 around the rotation axis 47; in this way it is possible to rotate the tank 46 around the rotation axis 47 without letting the quantities 5 of tobacco descend towards the tubular casings 2 in the corresponding filling station S2. This possibility (i.e. the rotation of the tank 46 around the rotation axis 47 without the descent of the quantities 5 of tobacco) is used when the manufacturing machine 8 is started, following a stop, so as to allow the formation of an uniform tobacco bed and with an adequate thickness inside the tank 46 before letting the quantities 5 of tobacco descend and when the manufacturing machine 8 is a function and, for some malfunctioning and/or discard in a filling station S2, there are not (all) the tubular casings 2 .

According to a possible embodiment, the actuator device 64 controls the sliding of the shutter elements 61 so that when the quantities 5 of tobacco have descended from the seats 49 each shutter element 61 (quickly) carries out a succession of strokes between the closing position and the opening position (i.e. opens and closes the seats 49 several times) in order to "shake" the seats 49 and therefore favour the descent of all the tobacco present inside the seats 49.

According to a possible embodiment illustrated in Figures 13 and 14, each filling unit 18 comprises a cleaning device 110, which is arranged in a fixed position (i.e. does not rotate with the tank 26) at the filling station S2 so as to perform the cleaning of the air-permeable plugs 62, namely to free the air-permeable plugs 62 from any tobacco residues "stuck" in the through holes of the plugs 62 before the seats 49 are filled with new quantities 5 of tobacco. In other words, after having emptied the seats 49 of the tank 46 by transferring the corresponding quantities 5 of tobacco from the seats 49 of the tank 46 to the seats 12 of a group 11 that is standing still in the filling station S2 and before starting again the filling of the seats 49 of the tank 46 with other tobacco in order to reform the quantities 5 of tobacco, the air-permeable plugs 62 are cleaned by means of the cleaning device 110 which eliminates any tobacco residues "stuck" in the through holes of the air-permeable plugs 62. It is important to note that the cleaning device 110 can clean the air-permeable plugs 62 at each cycle, every group of cycles (for example every 3-5 cycles), or occasionally.

According to a preferred embodiment, the cleaning device 110 directs powerful compressed air jets at the air-permeable plugs 62 to free the through holes of the air-permeable plugs 62 from any foreign objects; consequently, for each air-permeable plug 62 the cleaning device 110 comprises (at least) a corresponding nozzle which directs a compressed air jet at the plug 62. According to a possible embodiment, the cleaning device 110 is arranged beside the seats 49 in order to act on the air-permeable plugs 62 when the plugs 62 are moved away from the seats 49 by the movement of the shutter element 61; in this embodiment, the air-permeable plugs 62 are cleaned by the cleaning device 110 when they are (relatively) far from the seats 49, i.e. when the seats 49 are opened at the bottom to release the corresponding quantities 5 of tobacco. According to an alternative embodiment, the cleaning device 110 is arranged at the seats 49 to act on the air-permeable plugs 62 when the plugs 62 are coupled to the seats 49; obviously this cleaning is done after having extracted the quantities 5 of tobacco from the seats 49 and before starting the entry of new tobacco into the seats 49.

As illustrated in Figures 16 and 17, the pads 6 of filtering material are obtained by means of the transverse cut of corresponding pieces 65 of filtering material; i.e. the pieces 65 of filtering material are "sliced" in order to obtain the pads 6 of filtering material. In this regard, it is important to note that the axial length of each piece 65 of filtering material is equal to an internal multiple of the axial length of a pad 6 of filtering material; for example, each piece 65 of filtering material could have an axial length of 114 mm and each pad 6 of filtering material has an axial length of 4.75 mm (therefore, from each piece 65 of filtering material, twenty-four pads 6 of filtering material are obtained) .

The feeding unit 19 (illustrated as a whole in Figure 15) comprises a supply device 66 which supplies a group of pieces 65 of filtering material; in the embodiment illustrated in the accompanying figures, said group comprises fourteen pieces 65 of filtering material, or a number of pieces 65 of filtering material equal to the number of seats 12 in a line of a group 11. Furthermore, the feeding unit 19 comprises a cutting device 67 which cyclically carries out a transverse cut of the group of pieces 65 of filtering material in order to separate a respective group of pads 6 of filtering material from the group of pieces 65 of filtering material. Finally, the feeding unit 19 comprises a transfer device 68 which picks up the group of pads 6 of filtering material immediately after the transverse cut and inserts the pads 6 of filtering material into the corresponding seats 12 of a group 11 that is standing still in the feeding station S3.

The supply device 66 comprises a hopper 69 (better illustrated in Figure 18) provided with a group of vertical channels 70 which receive a plurality of pieces 65 of filtering material; along the vertical channels 70 the pieces 65 of filtering material descend by gravity until reaching a lower portion at which the pieces 65 of filtering material are axially extracted from the hopper 69 (i.e. they are axially pushed out from the hopper 69) . The supply device 66 comprises a group of horizontal pushers 71 (only one of which is visible in Figures 16 and 17), each engaging a lower portion of a corresponding vertical channel 70 so as to progressively push a piece 65 of filtering material out of the vertical channel 70 and towards the cutting device 67.

According to a preferred embodiment, the pieces 65 of filtering material come from individual trays which are loaded into an upper hopper and then supplied to a deep reaching drum which, by means of a pair of blades mounted on the same axis, removes the end portions of each filter for the purpose both of obtaining pieces 65 of filtering material of the desired length with a precision in the length higher than the initial one and of removing the ends which could have dents or wrinkles due to storage and transport. The flow of the trimmed pieces 65 of filtering material is brought to a height and conveyed by means of traditional down-drop inside a vertical chimney which feeds the hopper 69, in which the pieces 65 of filtering material are separated and spaced apart by step to then fall, one row at a time, at the base of the hopper 69 where the horizontal pushers 71 extract the pieces 65 of filtering material.

According to a preferred embodiment, each horizontal pusher 71 has a free end which comes into contact with a corresponding piece 65 of filtering material (i.e. with a base wall of the piece 65 of filtering material opposite the cutting device 67) and is provided with suction (i.e. is adapted to hold the piece 65 of filtering material by means of suction) .

As illustrated in Figures 16 and 17, the supply device 66 comprises an actuator device 72 which imparts a work cycle to the group of horizontal pusher 71, comprising: a first forward stroke, which brings the pieces 65 of filtering material from the lower portion of the vertical channels 70 to the cutting device 67, a subsequent plurality of second forward strokes each having a range equal to the axial size of the pad 6 of filtering material, and finally one single backward stroke which moves the horizontal pusher 71 away from the cutting device 67 returning the horizontal pushers 71 out of the vertical channels 70. In other words, initially each horizontal pusher 71 is arranged completely outside of the corresponding vertical channel 70 so as to allow the complete descent of a piece 65 of filtering material which then reaches the lower portion of the hopper 6_9; at this point each horizontal pusher 71 carries out the first forward stroke during which the horizontal pusher 71 enters the lower portion of the hopper 69 and pushes the piece 65 of filtering material out of the lower portion of the hopper 6_9 until it reaches the cutting device 67. Once the cutting device 67 has been reached, each horizontal pusher 71 carries out in succession the second forward strokes in order to allow the cutting device 67 to "slice" the piece 65 of filtering material a little at a time thus obtaining the pads 6 of filtering material. Once the piece 65 of filtering material has been completely "sliced" , each horizontal pusher 71 carries out the backward stroke to exit again from the corresponding vertical channel 70, thus allowing the complete descent of a new piece 65 of filtering material and starting again the work cycle.

Preferably, the actuator device 72 comprises its own electric motor which linearly moves the horizontal pusher 71 and individually and independently performs every single second forward stroke; in this way, the actuator device 72 cannot always make the same error in the length in the second outward strokes and therefore does not "sum" any errors in the length of the second outward strokes, thus preventing the last pads 6 of filtering material from being excessively thin or excessively thick as they suffer the sum of all errors in the length of the second forward strokes accomplished in succession during all the second forward strokes.

As illustrated in Figure 18, the cutting device 67 comprises a rotary blade 73 which is orientated perpendicularly to the pieces 65 of filtering material and is moved forwards and backwards by a conveyor belt 74; at each stroke of the rotary blade 73 (i.e. at each translation of the blade 73 rotating from one end of the hopper 69 to the opposite end of the hopper 69), the rotary blade 73 carries out the transverse cut of all the pieces 65 of filtering material. The rotary blade 73 operates within an opposing element 75 which keeps the pieces 65 of filtering material still and locked during the transverse cut; in particular, the opposing element 75 comprises a plurality of cutting channels through which the pieces 65 of filtering material pass with minimal gap (so that the pieces 65 of filtering material cannot "shake" inside the cutting channels ) and a slit open at the bottom through which the rotary blade 73 passes (always with minimal gap) when it carries out the transverse cut.

According to a preferred embodiment, mechanical safety locks are provided which enable (allow) the opening of the front doors of the hopper 69 (typically for eliminating a clogging of the pieces 65 of filtering material) only when the rotary blade 73 (which is very sharp, therefore with highly cutting edges) is arranged all on one side (i.e. outside the area affected by the hopper 69) ; moreover, further mechanical safety devices are provided which prevent (lock) the displacement of the rotary blade 73 when the front doors of the hopper 69 are open. In this way, an operator when opening the front doors of the hopper 69 is always in a safe condition because it cannot come into contact (even accidentally) with the rotary blade 73.

As illustrated in Figures 16 and 17, the transfer device 68 comprises a group of sucking holding heads 76 (only one of which is visible in Figures 16 and 17) mounted movable and adapted for engaging corresponding pads 6 of filtering material; obviously the number of holding heads 76 is equal to the number of pieces 65 of filtering material which, as previously said, is equal to the number of seats 12 in a line of a group 11.

Furthermore, the transfer device 68 comprises an actuator device 77 which is adapted to cyclically move each holding head 76 between a holding position (illustrated in Figure 16) in which the holding head 76 engages a pad 6 of filtering material at the moment of the execution of the transverse cut which separates the pad 6 of filtering material from the corresponding piece 65 of filtering material and a release position (illustrated in Figure 17) in which the holding head 76 releases a corresponding pad 6 of filtering material. Each holding head 76 can engage a pad 6 of filtering material immediately before or immediately after the execution of the transverse cut which separates the pad 6 of filtering material from the corresponding piece 65 of filtering material; in particular, when each holding head 76 engages a pad 6 of filtering material immediately after performing the transverse cut, the holding head 76 is arranged very close (for example fractions of a millimetre) and without contact at the end of the piece 65 of filtering material, before performing the transverse cut, and then "capture" by suction the pad 6 of filtering material by means of suction immediately after the transverse cut. The actuator device 77 comprises an arm, which is mounted movable on a frame of the manufacturing machine 8 to perform a roto-translat ion movement so as to move between the holding position (illustrated in Figure 16) and the release position (illustrated in the Figure 17) .

The transfer device 68 comprises, furthermore, a tray 78 which is arranged above the manufacturing drum 9 and is provided with a group of through-delivering channels 79, each crossing the tray 78 from side to side and adapted to contain a pad 6 of filtering material; the number and the arrangement of the through-delivering channels 79 are the same as the seats 12 of the manufacturing drum 9, therefore forty-two delivering channels 79 are provided, aligned along three straight lines, which are parallel to one another (each of the three straight lines has fourteen delivering channels 79) .

As better illustrated in Figure 19, each delivering channel 79 has an inlet opening (upper, i.e. obtained through an upper wall of the tray 78) through which a corresponding pad 6 of filtering material enters the delivering channel 79 and an outlet opening (lower, i.e. obtained through a lower wall of the tray 78) which is opposite the inlet opening and through which a corresponding pad 6 of filtering material exits the delivering channel 79.

According to a preferred embodiment illustrated in Figure 19, each delivering channel 79 is funnel-shaped, i.e. it has a progressively decreasing cross section, for transversely compressing a corresponding pad 6 of filtering material during the passage of the pad 6 of filtering material along the delivering channel 79. Accordingly, when a pad 6 of filtering material exits the corresponding delivering channel 79, the pad 6 of filtering material itself is elastically compressed to have a reduced diameter and therefore being able to easily enter into a corresponding tubular casing 2. The funnel shape of the delivering channels 79 is also used to block the pads 6 of filtering material inside the delivering channels 79: each holding head 76 inserts a corresponding pad 6 of filtering material inside a delivering channel 79 thus determining a given compression (elastic) of the pad 6 of filtering material itself and therefore "fitting with interference" the pad 6 of filtering material inside the delivering channel 79; consequently, the pad 6 of filtering material remains still within the delivering channel 79 without the need for any retaining element.

As illustrated in Figures 16 and 17, the tray 78 is mounted movable; for translating between a receiving position (illustrated in Figure 17) in which the delivery channels 79 are (relatively) far from the seats 12 of a group 11 that is standing still in the feeding station S3 and the holding heads 76 insert the pads 6 of filtering material in the corresponding delivering channels 79, and an insertion position (illustrated in Figure 16) in which the delivery channels 79 are aligned with the corresponding seats 12 of a group 11 that is standing still in the feeding station S3 so as to insert the pads 6 of filtering material into the tubular casings 2 carried by the seats 12. In particular, the transfer device 68 comprises an actuator device 80 for cyclically moving the tray 78 between the receiving position (illustrated in Figure 17) and the insertion position (illustrated in Figure 16) .

In use, the empty tray 78 (i.e. completely devoid of pads 6 of filtering material) is placed in the receiving position (illustrated in Figure 17) and therefore the group of holding heads 76 is cyclically moved between the holding position (illustrated in Figure 16) in which the holding heads 76 pick up new pads 6 of filtering material separated from the corresponding pieces 65 of filtering material and the release position (illustrated in Figure 17) in which the holding heads 76 release the corresponding pads 6 of filtering material in the insertion channels 79 of the tray 78. In particular, at each insertion cycle the fourteen holding heads 76 insert fourteen pads 6 of filtering material into fourteen delivering channels 79 which form a line (of three overall lines) of the group of delivering channels 79; as a consequence, the complete filling of the tray 78 requires three successive insertion cycles. According to a preferred embodiment, at the end of an insertion cycle the tray 78 is slightly translated by the actuator device 80 in order to arrange a line of fourteen empty delivery channels 79 at the release position (illustrated in Figure 17) of the holding heads 76; in other words, the holding heads 76 have a single release position (illustrated in Figure 17) which cannot be modified and therefore the tray 78 must be translated each time in order to arrange a line of fourteen empty delivery channels 79 at the release position (illustrated in Figure 17) of the holding heads 76. To summarize, the actuator device 80 (which is part of the transfer device 68) cyclically moves the tray 78 between three distinct receiving positions so as to insert the pads 6 of filtering material into the delivering channels 79 of three distinct delivering channels 79, respectively.

At the feeding station S3, the transfer device 68 comprises a group of forty-two pushers 81, each aligned in a vertical (longitudinal) manner with a corresponding delivering channel 79 when the tray 78 is arranged in the insertion position (illustrated in Figure 16); in this position, the pushers 81 are movable in a vertical manner (i.e. parallel to the delivering channels 79) to be inserted into the corresponding delivering channels 79 thus pushing the pads 6 of filtering material out of the delivering channels 79 and then into a corresponding tubular casing 2 carried by the seats 12 of a group 11 that is standing still in the feeding station S3.

According to a preferred embodiment, at the feeding station S3, the transfer device 68 comprises a group of forty-two pushers 82, each opposite to a corresponding pusher 81 (i.e. it is arranged on the opposite side of the corresponding pusher 81 relative to the manufacturing drum 9) and is aligned in a vertical (longitudinal) manner with a corresponding seat 12 of a group 11 that is standing still in the feeding station S3; the pushers 82 are movable in a vertical manner (i.e. parallel to the seats 12) to be inserted inside the seats 12 and to push the tubular casings 2 contained in the seats 12 towards the tray 78 and, hence, towards the corresponding delivering channels 79.

In use, when the tray 78 is full, i.e. all the delivering channels 79 of the tray 78 contain a corresponding pad 6 of filtering material, the actuator device 80 moves the tray 78 into the insertion position (illustrated in Figure 16) to align the delivering channels 79 to the seats 12 of a group 11 that is standing still in the feeding station S3. At this point, the pushers 82 enter from the bottom into the seats 12 to push the tubular casings 2 carried by the seats 12 towards the tray 78 (i.e. substantially in contact with the tray 78) while, at the same time, the pushers 81 enter the delivering channels 79 for pushing the corresponding pads 6 of filtering material out of the delivering channels 79 and then into the tubular casings 2. Once the pads 6 of filtering material have been inserted into the corresponding tubular casings 2, the pushers 81 retract by exiting the delivering channels 79 of the tray 78 and the pushers 82 retract by exiting the seat 12; at this point, the manufacturing drum 9 can perform a feed step and the cycle starts again.

According to a preferred embodiment illustrated in Figure 20, each delivering channel 79 has an indented (knurled) cross section and each pusher 81 has a pushing head which has an indented (knurled) cross section which reproduces, in negative, the indented cross section (knurled) of the corresponding delivering channel 7_9. The indented (knurled) shape of the pushers 81 allows the pushers 81 to press not only on the central part of the pads 6 of filtering material but also, and above all, on the peripheral paper ring which surrounds the central part of the pads 6 of filtering material; thus avoiding that the pushers 81 tend to extrude the central part of the pads 6 of filtering material from the peripheral paper ring which surrounds the central part. In other words, the "teeth" of the indentation (knurling) make it possible to maximize the pushing area on the paper to avoid damaging it and the slots between two "teeth" of the indentation (knurling) allow to accommodate the overabundance of paper that is generated in the transverse compression step.

As illustrated in Figure 21, the seats 12 of a group 11 that is standing still in the transfer station S4 are vertically aligned with the corresponding seats 16 of a group 15 that is standing still in the transfer station S4. The transfer unit 20 comprises a group of (forty-two) pushers 83, which are arranged in the transfer station S4 and are movable in a vertical manner so as to be inserted into the seats 12 of a group 11 that is standing still in the transfer station S4 thus pushing the tubular casings 2 from the seats 12 of a group 11 that is standing still in the transfer station S4 to the seats 16 a group 15 that is standing still in the transfer station S4; moreover, the transfer unit 20 comprises a group of (forty-two) accompanying elements 84 which are opposite to the pushers 83 and are movable in a vertical manner to accompany the ascent of the tubular casings 2 from the seats 12 of the manufacturing drum 9 to the seats 16 of the manufacturing drum 13.

In other words, in the transfer station S4 each tubular casing 2 is transferred from a seat 12 of a group 11 that is standing still in the transfer station S4 to the overlying seat 16 of a group 15 that is standing still in the transfer station S4 by performing a vertical ascent movement during which the tubular casing 2 is engaged at the bottom by a pusher 83 and at the top by an accompanying element 84 (i.e. by being "pinched" between a pusher 83 arranged at the bottom and by an accompanying element 84 arranged at the top) . In this regard it is important to note that accompanying elements 84 would not be strictly necessary; however, the presence of the accompanying elements 84 allows to impart a controlled movement to the tubular casings 2 which prevents any incorrect positioning or bouncing of the tubular casings 2.

As previously stated, each seat 16 of the manufacturing drum 13 comprises a through housing channel 26 which passes through the manufacturing drum 13 from side to side and is adapted to contain a tubular casing 2 and a pair of opposite jaws 27, which are fitted in the housing channel 26 and are movable between a holding position, in which they engage a tubular casing 2 arranged in the housing channel 26 and a transfer position, in which they do not engage a tubular casing 2 arranged in the housing channel 26. During the entering of a tubular casing 2 into a corresponding seat 16 of the manufacturing drum 13, the two jaws 27 are kept in the transfer position and only when the entering of the tubular casing 2 into the seat 16 has been completed, then, the two jaws 27 are brought into the holding position.

The feeding unit 21 feeds the sealing rings 7 to the tubular casings 2 carried by the corresponding seats 16 of a group 15 that is standing still at the feeding unit 21 (i.e. that is standing still in the feeding station S5) . The sealing unit 7 of the sealing rings 7 is very similar (but not perfectly identical) to the feeding unit 17 of the tubular casings 2 described above.

As illustrated in Figure 22, the feeding unit 21 comprises a feeding drum 85 (having a parallelepiped shape) which is mounted rotating in a stepwise manner around a rotation axis 86 parallel to the rotation axis 14 of the manufacturing drum 13; the feeding drum 85 supports two groups 87 of opposite fingers 88 (i.e. the two groups 87 are arranged on opposite sides of the rotation axis 85) . Each group 87 comprises fourteen fingers 88 which are parallel and side-by-side one another and each finger 88 has three seats 89 each adapted to receive a corresponding sealing ring 7; it is important to note that the number of seats 89 of each finger 88 is equal to the number of lines of each group 15 of seats 16 of the manufacturing drum 13. As illustrated in Figures 23 and 24 each seat 89 is formed by a through hole which is obtained inside the corresponding finger 88, passes through the corresponding finger 88 from side to side and is adapted to contain a corresponding sealing ring 7.

Each group 87 of fingers 88 is adapted to receive corresponding sealing rings 7 (in particular forty-two sealing rings 7) in an insertion station S9 and is adapted to release the sealing rings 7 (in particular forty-one sealing rings 7) to the group 15 of seats 16 of the manufacturing drum 13 in the feeding station S5. Furthermore, each finger 88 is mounted on the feeding drum 85 to translate relative to the feeding drum 85 along a separating direction D3 perpendicular to the rotation axis 86 so as to move away from or closer to the adjacent fingers 88. The feeding drum 85 is provided with an actuator device 90 which moves the fingers 88 along the separating direction D3 so as to place the fingers 88 at a first mutual distance in the insertion station S9 and at a second mutual distance, which is different from the first mutual distance, in the feeding station S5; in the embodiment illustrated in the accompanying figures, the second mutual distance is greater than the first mutual distance.

In the embodiment illustrated in the accompanying figures, the fingers 88 of each group 87 move with respect to the others by means of a translation along the separating direction D3; according to a different and perfectly equivalent embodiment not illustrated, the fingers 88 of each group 87 move with respect to the others by a roto-translation or by a rotation which has a component along the separating direction D3.

The function of the actuator device 90 is to modify the pitch (i.e. the mutual distance) between the sealing rings 7 which, in the embodiment illustrated in the attached figures, have a 9.5 mm pitch in the insertion station S9 and have a 12 mm pitch in the feeding station S5. The increase in the pitch (i.e. the mutual distance) between the sealing rings 7 is clearly visible in Figure 22 which shows the fingers 88 (carrying the seats 89) in the feeding station S5 (pitch equal to 12 mm) and in the insertion station S9 (pitch equal to 9.5 mm) . According to a preferred embodiment, the actuator device 90 is a passive one (i.e. it has no sources which autonomously generate a movement) and uses cams which translates the fingers 88 by using the rotation movement of the feeding drum 85 around the rotation axis 86; according to a preferred, but not binding, embodiment, the cam actuator device 90 is of the desmodromic type devoid of elastic elements, i.e. the translation movement of the fingers 88 is always imparted by cams which move the fingers 88 in both directions without using elastic thrust.

It is important to note that, according to different embodiments equivalent to one another, the actuator device 90 can translate the fingers 88 of each group 87 into the feeding station S5 (when the feeding drum 28 is standing still), in the insertion station S9 (when the feeding drum 28 is standing still) or in the path between the feeding station S5 and the insertion station S9 (when the feeding drum 28 is moving) .

As illustrated in Figure 22, the feeding unit 21 comprises three conveying channels 91 which are inclined downwards (but may also be horizontal) and feed by gravity (by using downwards inclination) three respective rows of sealing rings 7 towards the insertion station S9; as is evident in Figure 22, in the insertion station S9 each conveying channel 91 is coupled (aligned) with a corresponding seat 89 in each finger 88. As better illustrated in Figure 23, each conveying channel 91 is laterally delimited by corresponding sides 92 (which can be singular as illustrated in the attached figures, double, or triple) and is delimited, at the bottom, by a support plane 93. The conveying channels 91 can feed the respective rows of sealing rings 7 solely by gravity (by exploiting the downward inclination) or by adding compressed air blowers (blower air conveyor) or vibrations (vibrating conveyor) ; alternatively, other configurations of the conveying channels 91 are also possible with the only constraint that the conveying channels 91 feed the respective rows of sealing rings 7 towards the insertion station S8.

As illustrated in Figure 22, the feeding unit 21 also comprises an accompanying element 94 which has three parallel prongs, each of which is coupled to a corresponding conveying channel 91; in particular, the accompanying element 94 is movable within the conveying channels 91 and parallel to the conveying channels 91 to accompany the progressive descent of the sealing rings 7 inside the insertion station S9. Moreover, the feeding unit 21 comprises a gate 95 which is coupled to the conveying channels 91, is arranged immediately upstream of the insertion station S9 (i.e. it delimits the beginning of the insertion station S9) and is movable between an opening position, in which it allows the sealing rings 7 to enter into the insertion station S9 and a closing position which prevents the sealing rings 7 from entering the insertion station S9.

In use, when the insertion station S9 is full (i.e. when in the insertion station S9 there are forty-two sealing rings 7 arranged in three rows of fourteen sealing rings 7 in the three conveying channels 91 as illustrated in Figure 22), the gate 95 is closed (i.e. is arranged in the closing position) so as to "isolate" the sections of the conveying channels 91 comprised in the insertion station S9 from the remaining sections of the conveying channels 91 and then the forty-two sealing rings 7 in the insertion station S9 are transferred (with the methods described in the following) from the conveying channels 91 to the seats 89 of the fingers 88 of a group 87 that is standing still in the insertion station S9. When the forty-two sealing rings 7 in the insertion station S9 have been transferred from the conveying channels 91 to the seats 89 of the fingers 88 of a group 87 that is standing still in the insertion station S9, the insertion station S9 is empty (i.e. completely devoid of sealing rings 7) ; at this point, the prongs of the accompanying device 94 are fed along the conveying channels 91 until reaching the gate 95 and therefore the gate 95 is opened (i.e. is arranged in the opening position) so as to allow the sealing rings 7 to enter the insertion station S9 again, sliding by gravity along the three conveying channels 91; the descent of the sealing rings 7 along the three conveying channels 91 and in the insertion station S9 is not free (i.e. uncontrolled) but is controlled by the three prongs of the accompanying element 94 which rest on the corresponding first three sealing rings 7 to accompany at a controlled and predetermined speed the descent of the first three sealing rings 7 (followed by the other sealing rings 7) along the three conveying channels 91. Due to the action of the accompanying element 94, the sealing rings 7 are never "abandoned" and therefore have no possibility of "tipping over" inside the conveying channels 91.

According to a preferred embodiment, the gate 95 comprises, for each conveying channel 91, a corresponding wedge-shaped stop element which is inserted (in the closing position) between two successive sealing rings 7 to prevent further advancement of the sealing ring 7 arranged upstream along the conveying channel 91.

According to a possible embodiment illustrated in Figure 22, a video camera T is provided which frames the three conveying channels 91 at the gate 95 so as to detect the exact (actual) position of the sealing rings 7 inside the three conveying channels 91; in this way, the movement of the accompanying device 94 inside the conveying channels 91 is controlled based on the actual (exact) position of the sealing rings 7 inside the conveying channels 91 so that the gate 95 can be moved from the opening position to the closing position by enclosing the correct number of sealing rings 7 behind it and without being pressed against the sealing rings 7 themselves. In other words, the actual (exact) position of the sealing rings 7 within the three conveying channels 91 is not left the "chance" by means of an open-loop control of the movement of the accompanying element 94, but the actual (exact) position of the sealing rings 7 inside the three conveying channels 91 is guaranteed by a closed-loop control of the movement of the accompanying element 94 (by using, as a feedback variable, the position of the sealing rings 7 inside the three conveying channels 91 detected by the video camera T) . In this regard it is important to note that the sealing rings 7 (unlike the tubular casings 2) are elastically deformable and therefore, due to possible elastic deformation, the position of the sealing rings 7 inside the three conveying channels 91 can be (slightly) variable in a substantially unpredictable way; said unpredictability is detected and compensated by means of the video camera T which is able to accurately determine the actual position of the sealing rings 7 inside the three conveying channels 91 and therefore to control (adapt, correct) accordingly, the movement of the accompanying element 94.

According to a possible embodiment, even or only the movement of the gate 95 (particularly the movement from the opening position to the closing position) is synchronized with the exact position of the sealing rings 7 inside the three conveying channels 91 in order to avoid errors in the handling of the gate 95. In other words, the movement of the gate 95 is controlled according to the exact position of the sealing rings 7 inside each conveying channel 91 detected by the video camera T in combination or alternatively to control the movement of the accompanying element 94 as a function of the exact position of the sealing rings 7 inside each conveying channel 91 detected by the video camera T.

As illustrated in Figure 23, in the insertion station S9 the seats 89 of the fingers 88 are aligned with the corresponding conveying channels 91 and are arranged below the corresponding conveying channels 91 so that each sealing ring 7 carried by a conveying channel 91 is vertically aligned with a corresponding seat 89 of the fingers 88. As previously stated, the conveying channels 91 comprise a support plane 93 on which the tubular casings 2 rest. In the insertion station S9, the support plane 93 has a plurality of through holes 96, each smaller than a sealing ring 7; unlike the feeding unit 17, in the feeding unit 21 the support plane 93 is fixed, i.e. it is devoid of moving parts.

As illustrated in Figure 23, the feeding unit 21 comprises a group of (forty-two) pushers 97 which are arranged in the insertion station S9 and are movable in a vertical manner so as to push the sealing rings 7 from the conveying channel 91 to the seats 89 of the fingers 88 of a group 87 that is standing still in the insertion station S9; moreover, the feeding unit 21 comprises a group (forty two) of accompanying elements 98 which are opposite to the pushers 97 and are movable in a vertical manner so as to be inserted into the seats 89 of the fingers 88 of a group 87 that is standing still in the insertion station S9 and to accompanying the ascent of the sealing rings 7 from the conveying channel 91 to the seats 89 of the fingers 88. In other words, in the insertion station S9 each sealing ring 7 is transferred from a conveying channel 91 to the overlying seat 89 of a finger 88 of a group 87 that is standing still in the insertion station S9, carrying out a vertical upward movement during which the sealing ring 7 is engaged, at the bottom, by a pusher 97 and, at the top, by an accompanying element 98 (i.e. being "pinched" between a pusher 97 arranged at the bottom, and by an accompanying element 98 arranged at the top) . In this regard it is important to note that accompanying elements 98 would not be strictly necessary; however, the presence of the accompanying elements 98 allows to impart a controlled movement to the sealing rings 7, which prevents any incorrect positioning or bouncing of the sealing rings 7.

In the seats 89 of the fingers 88, the sealing rings 7 are held by mechanical interference, i.e. the pushers 97 "fit with interference" the sealing rings 7 inside the seats 89 of the fingers 88 thus causing a (small) elastic deformation of the sealing rings 7. In this regard, the inlet opening (i.e. the lower opening) of each seat 89 can have a flared shape (i.e. a funnel shape, a taper-conical shape) to allow easy entering of a corresponding sealing ring 7 and then a subsequent gradual compression of the sealing ring itself as it goes up again into the seat 89.

As illustrated in Figure 24, the seats 89 of the fingers 88 of a group 87 that is standing still in the feeding station S5 are aligned and overlap the corresponding seats 16 of a group 15 that is standing still in the feeding station S5 so that each sealing ring 7 carried by a seat 89 of the fingers 88 is vertically aligned with a corresponding seat 16 of the manufacturing drum 13. The feeding unit 21 comprises a group (forty-two) of pushers 99 which are arranged in the feeding station S5 and are movable in a vertical manner so as to be inserted into the seats 89 of the fingers 88 of a group 87 that is standing still in the feeding station S5 thus pushing the sealing rings 7 from the seats 89 of the fingers 88 to the seats 16 of a group 15 that is standing still in the feeding station S5. Moreover, the feeding unit 21 comprises a group (forty-two) of pushers 100, each opposite a corresponding pusher 99 (i.e. is arranged on the opposite side of the corresponding pusher 99 with respect to the manufacturing drum 13) and is aligned in a vertical (longitudinal) manner with a corresponding seat 16 of a group 15 that is standing still in the feeding station S5; the pushers 100 are movable in a vertical manner (i.e. parallel to the seats 16) to be inserted inside the seats 16 and push the tubular casings 2 contained in the seats 16 towards the fingers 88 and, hence, towards the corresponding seats 89.

In other words, in the feeding station S5 each sealing ring 7 is transferred from a seat 89 of a finger 88 of a group 87 that is standing still in the feeding station S5 to the underlying seat 16 of a group 15 that is standing still in the feeding station S5 by performing a vertical downward movement during which the sealing ring 7 is engaged, at the top, by a pusher 99; at the same time, each tubular casing 2 carried by a corresponding seat 16 of a group 15 that is standing still in the feeding station S5 is pushed upwards by a pusher 100 to exit from the seat 16 and approach the corresponding finger 88. When the sealing ring 7 comes into contact with a corresponding tubular casing 2, the sealing ring 7 is fitted around an upper portion of the sealing ring 7 as illustrated in Figure 1. The main function of the pusher 100 is to lift the tubular casings 2 from the jaws 27 of the seats 16 and "back-up" (i.e. provide a adapted lower support) when the sealing rings 7 are fitted around the corresponding tubular casings 2; therefore in this step the jaws 27 of the seats 16 are in no way mechanically stressed, since the contrast necessary to fit the sealing rings 7 around the corresponding tubular casings 2 is provided solely by the pusher 100.

As illustrated in Figure 25, each welding unit 22 comprises a group of ultrasonic welding devices 101 (only one of which is illustrated in Figure 25) formed by a number of welding devices 101 equal to the number of seats 16 of a same line of seats 16 (i.e. in the embodiment illustrated in the attached figures, fourteen welding devices 101) . When a group 15 of seats 16 stops in a welding station S6, all of only the seats 16 of a same line of seats 16 are coupled to corresponding welding devices 101 which perform an annular welding between each tubular casing 2 and the corresponding sealing ring 7 previously fitted in the feeding station S5. According to a preferred embodiment, each welding device 101 comprises a sonotrode 102 which is placed in contact with an upper end of the corresponding tubular casing 2 carrying the sealing ring 7 and has the function of transmitting the vibrations, in an ultrasonic field, to the tubular casing 2 carrying the sealing ring 7; furthermore, each welding device 101 comprises an anvil 103 which is opposite to the sonotrode 102 and is arranged in contact with a lower end of the corresponding tubular casing 2 (i.e. with the bottom wall 3 of the corresponding tubular casing 2) and has both the function of providing a contrast to the sonotrode 102, and of pushing the tubular casing 2 from the bottom towards the sonotrode 102 (i.e. in close contact with the sonotrode 102) while simultaneously separating the tubular casing 2 from the corresponding jaws 27 of the seat 16. According to a preferred embodiment, the anvils 103 of all the welding devices 101 form a single monolithic body mounted in a fixed position next to the lower face of the conveying drum 13; moreover, the anvils 103 of all the welding devices 101 present at the beginning and at the end of the inclined planes, so as to make progressively both the ascent upward movement of the tubular casings 2 (i.e. towards the sonotrodes 102), and the subsequent descent downward movement of the tubular casings 2.

It is important to underline that during the welding each tubular casing 2 must be separated from the corresponding jaws 27 so as to rest only on the bottom of the corresponding anvil 103, since only the anvils 103 are sufficiently rigid to provide an adequate contrast for the ultrasonic welding.

According to a preferred embodiment, each sonotrode 102 is mounted to the frame by means of the interposition of an elastic element (for example a pneumatic spring) so as to constantly exert a constant pressure on the sealing ring 7 when the corresponding tubular casing 2 is pushed against the sonotrode 102 by the underlying anvil 103. In other words, the anvils 103 always lift the tubular casings 2 with the same stroke and the adjustments to compensate the constructive tolerances are performed by the sonotrodes 102 which translate in a vertical manner thus compressing the corresponding elastic elements.

For example, each welding device 101 can be made as described in the patent application IT102016000094855 to which reference should be made for further details.

As illustrated in Figure 26, in the output station S7 the extraction unit 23 transfers the disposable cartridges 1 (i.e. the tubular casings 2 provided with the corresponding quantities 5 of tobacco, pads 6 of filtering material and sealing rings 8) from the seats 16 of a group 15 that is standing still in the output station S7 to three conveying channels 104 which are inclined downwards and feed, by gravity (by exploiting the downward inclination) three respective rows of disposable cartridges 1 towards the output of the manufacturing machine 1 (passing through an optical control station, a weight control station, and a station for discarding the non-compliant disposable cartridges) . As is evident in Figure 7, each conveying channel 104 is coupled (aligned) to a corresponding line of seats 16 of a group 15 that is standing still in the output station S7. According to a preferred embodiment illustrated in Figure 26, each conveying channel 104 is laterally delimited by corresponding sides 105 (which can be double as illustrated in the attached figures, single, or triple) and is delimited, at the bottom, by a support plane 106.

The extraction unit 23 comprises a group (forty-two) of pushers 107 which are arranged in the output station S7 and are movable in a vertical manner so as to push the disposable cartridges 1 from the seats 16 of a group 15 that is standing still in the output station S7 to the corresponding conveying channels 106; moreover, the extraction unit 23 comprises a group (forty-two) of accompanying elements 108 which are opposite to the pusher 107 and are movable in a vertical manner to accompany the descent from the seats 16 of a group 15 that is standing still in the output station S7 to the corresponding conveying channels 106. The support plane 106 of the conveying channels 104 has a plurality of through holes 109 (smaller than the disposable cartridges 1) through which the accompanying elements 108 can reach, from the bottom, the seats 16 of a group 15 that is standing still in the output station S7.

In other words, in the output station S7 each disposable cartridge 1 is transferred from a seat 16 of a group 15 that is standing still in the output station S7 to an underlying conveying channel 106 thus carrying out a vertical downward movement during which the disposable cartridge 1 is engaged, at the top, by a pusher 107 and, at the bottom, by an accompanying element 108 (i.e. by being "pinched" between a pusher 107 arranged at the top and by an accompanying element 108 arranged at the bottom) . In this regard it is important to note that pushers 107 and the accompanying elements 108 would not be strictly necessary, since the vertical descent movement would in any case be imparted on the disposable cartridges 1 by the force of gravity; however, the presence of the pushers 107 and of the accompanying elements 108 allows to impart a controlled movement to the disposable cartridges 1, which prevents any incorrect positioning or bouncing of the disposable cartridges 1.

As illustrated in Figure 27, a discarding device 111 is arranged along the three conveying channels 104 and downstream of the output station S7 (i.e. downstream of the extraction unit 23 and outside of the manufacturing drum 13), which is adapted to remove and discard disposable cartridges 1 from a corresponding conveying channel 104; for example, the discarding device 111 could be controlled so as to discard a group of fourteen disposable cartridges 1 (i.e. a number of disposable cartridges 1 equal to the number of seats 12 and 16 in each line of each group 11 and 15) from a corresponding conveying channel 104. In particular, for each conveying channel 104 the discarding device 111 comprises a respective motorized deviator element which acts as a "railway exchange" in order to divert the disposable cartridges 1 which advance along the conveying channel 104 towards a discarding direction; preferably, the disposable cartridges 1 diverted by the deviator element are directed towards an underlying collecting container in which they fall by gravity.

The discarding device 111 can be actuated by an operator to extract samples of the disposable cartridges 1, it can be actuated automatically when some problems have been detected during the manufacturing of the disposable cartridges 1 (for example the failure in supplying the tubular casings 2, the quantities 5 of tobacco, the pads 6 of filtering material, or the sealing rings 7 or the failure of the welding devices 101); alternatively, the discarding device 111 can be actuated at the start/stop of the manufacturing machine 8 in order to eliminate the disposable cartridges 1 produced as first/last (therefore potentially incomplete) . Alternatively or as addition, the manufacturing machine 8 could comprise control devices (typically optical by means of video cameras) which are arranged at the manufacturing drums 9 and 13 to detect any defects and therefore discard the defective disposable cartridges 1 by means of the discarding device 111 arranged downstream of the manufacturing drums 9 and 13.

As illustrated in Figure 27, three respective control stations S10 are arranged along the three conveying channels 104; for this purpose the three conveying channels 104 are initially side-by-side one another (i.e. they are beside one another at the output station S7 and at the discarding device 111), they separate from one another (i.e. they move away from one another) to create the space necessary to the corresponding control stations S10, and finally meet again at an output of the manufacturing machine 8 towards a subsequent packing machine .

Each control station S10 comprises a control unit 112 which carries out an external optical control (typically by means of video cameras) and a weight control for each disposable cartridge 1 and therefore discards the disposable cartridges 1 which are not compliant (i.e. showing visible surface defects and/or not having the required weight within a given tolerance) . Furthermore, each control station S10 comprises a feeding drum 113 which is interposed along a corresponding conveying channel 104, i.e. locally interrupts the conveying channel 104; in other words, each conveying channel 104 temporarily transfers the disposable cartridges 1 to the corresponding feeding drum 113 from which it receives, again, the disposable cartridges 1 after the controlling and discarding operations.

Each feeding drum 113 is arranged horizontally and is mounted rotating in a stepwise manner or with continuous motion around a vertical rotation axis 114; in other words, each feeding drum 113 is set into rotation with an intermittent motion, i.e. a non-continuous motion which provides a cyclical alternation of motion steps, in which the feeding drum 113 is moving, and still steps, in which the feeding drum 113 stops, or, according to an alternative embodiment, each feeding drum 113 is set into rotation with a continuous motion which does not provide stops. Each feeding drum 113 has a plurality of peripheral seats 115 (i.e. arranged on the outer periphery of the feeding drum 113 and open towards the outside of the feeding drum 113 itself), each adapted to receive and contain a corresponding disposable cartridge 1 so as to feed the disposable cartridge 1 along a circular path between an input (in which the corresponding conveying channel 104 arrives) and an output (in which the corresponding conveying channel 104 starts again) .

Each control unit 112 comprises an optical control device 116 (adapted to capture a complete, i.e. 360°, image of each disposable cartridge 1 through the use of particular optics) and a subsequent microwave control device 117 which measures the weight of the quantity 5 of tobacco contained in each disposable cartridge 1. In particular, the microwave control device 117 uses microwaves to determine the weight of the quantity 5 of tobacco contained in each disposable cartridge 1 since the microwaves are sensitive to water (moisture) of the tobacco. According to a possible embodiment, each optical control device 116 comprises at least one video camera (but two or three video cameras may also be used) coupled to one or more mirrors which allow the video camera to also frame the hidden faces of each disposable cartridge 1; in other words, the video camera can directly see only one part of each disposable cartridge 1, while the remaining unseen portion of each disposable cartridge 1 is viewed indirectly through the reflected image in one or more suitably positioned mirrors.

Finally, each control station S10 comprises a discarding device 118 which is coupled to the corresponding feeding drum 113 downstream of the control unit 112 (i.e. downstream of the optical control device 116 and of the microwave control device 117) and is adapted to extract from the corresponding seat 115 a non-compliant (i.e. defective) disposable cartridge 1 previously detected by the control unit 112.

According to the alternative embodiment illustrated in Figures 28, 29 and 30, the insertion station S8 comprises a centring device 119, which arranges the tubular casings 2 (in particular the forty-two tubular casings 2 arranged in three rows) in the correct position (i.e. in perfect vertical alignment with the corresponding seats 32 of the underlying fingers 31 of a group 30 that is standing still in the insertion station S8) so as to allow a subsequent precise and smooth transfer of the tubular casings 2 from the conveying channels 34 to the underlying fingers 31 of a group 30 that is standing still in the insertion station S8.

The centring device 119 comprises three centring elements 120 (better illustrated in Figure 30), each of which is "saw tooth" shaped (i.e. it has fourteen seats side-by-side which reproduce in negative part of the outer shape of the tubular casings 2) and is linearly movable between a rest position (illustrated in Figure 28) and a work position (illustrated in Figure 29) . In the rest position (illustrated in Figure 28), each centring element 120 is offset (i.e. relatively far) from the tubular casings 2 carried by the corresponding conveying channel 34 and therefore does not interact in any way with the tubular casings 2. In the work position (illustrated in Figure 29), each centring element 120 is in contact with the tubular casings 2 carried by the corresponding conveying channel 34 and therefore does not "constrain" the tubular casings 2 to assume a predetermined desired position (i.e. a position of perfect vertical alignment with the corresponding seats 32 of the underlying fingers 31 of a group 30 that is standing still in the insertion station S8) .

As illustrated in Figure 30, the centring device 119 comprises a support body 121 which supports the three centring elements 120 and is mounted in a movable manner to linearly translate between the rest position (illustrated in Figure 28) and the work position (illustrated in Figure 29) . An actuator device 122 (e.g. an electric motor) is coupled to the support body 121, which imparts the linear translation movement to the support body 121 itself. The support body 121 has two through openings 123, at which two centring elements 120 are arranged, while the third centring element 120 is arranged at an outer edge of the support body 121.

According to a preferred but non-binding embodiment, illustrated in Figure 30, the centring device 119 also integrates the gate 38 (or, from another point of view, the gate 38 also integrates the centring device 119) ; in other words, the centring device 119 and the gate 38 together form a single aggregate which carries out both tasks. In particular, each centring element 120 is provided with a wedge-shaped stop element 124 which is inserted (in the closing position) between two successive tubular casings 2 to prevent further advancement of the tubular casing 2 arranged upstream along the corresponding conveying channel 34. In other words, the stopping element 124 of each centring element 120 is movable together with the centring element 120 itself between the opening position (corresponding to the rest position of the centring element 120) in which it allows the tubular casings 2 to enter into the insertion station S8 and the closing position (corresponding to the work position of the centring element 120) which prevents the entering of the tubular casings 2 into the insertion station S8.

According to a different embodiment not illustrated, the centring device 119 can be completely separate and independent from the gate 38.

The centring device 119 can be operated to centre the tubular casings 2 in the insertion station S8 immediately before the start of the transfer of the tubular casings 2 or simultaneously with the start of the transfer. Moreover, once the centring device has been made (i.e. once the centring device 119 has been placed in the work position), the centring device 119 can be left in the work position until the transfer of the tubular casings 2 is completed, the centring device 119 can be left in the work position only during part of the transfer of the tubular casings 2 (i.e. the centring device 119 is placed in the rest position during the transfer of the tubular casings), or the centring device 119 can be arranged immediately after in the rest position (i.e. the centring device 119 is placed in the rest position before starting the transfer of the tubular casings 2 or coinciding with the start of the transfer of the tubular casings 2) .

According to the alternative embodiment illustrated in Figures 31 and 32, also the insertion station S9 comprises a centring device 126, which arranges the sealing rings 7 (in particular the forty-two sealing rings 7 arranged in three rows) in the correct position (i.e. in perfect vertical alignment with the corresponding seats 89 of the overlying fingers 88 of a group 87 that is standing still in the insertion station S9) so as to allow a subsequent precise and smooth transfer of the sealing rings 7 from the conveying channels 91 to the overlying fingers 88 of a group 87 that is standing still in the insertion station S8.

The centring device 126 of the insertion station S9 is completely identical to the centring device 119 of the insertion station S8 (to which refer for a detailed description of the device centring device itself) ; consequently, the centring device 126 also comprises three centring elements 127, each of which is "saw tooth" shaped (i.e. it has fourteen seats side-by-side which reproduce in negative part of the outer shape of the sealing rings 7) , it is linearly movable between a rest position (illustrated in Figure 31) and a work position (illustrated in Figure 32), and can integrate the gate 95.

In the embodiment illustrated in Figures 23, 31 and 32, at each conveying channel 91 the support plane 93 comprises a single row of through holes 96 through which the corresponding pushers 97 are inserted each having a single point; consequently, in the embodiment illustrated in Figures 23, 31 and 32, each pusher 97 centrally engages a corresponding sealing ring 7. In the alternative illustrated in Figure 33, at each conveying channel 91, the support plane 93 comprises two rows, side-by-side one another, of through holes 96 through which the corresponding pushers 97 are inserted each having two twin points facing one another; consequently, in the embodiment illustrated in Figure 33, each pusher 97 laterally engages a corresponding sealing ring 7 (this alternative is preferable as the sealing rings 7 have greater rigidity at the outer edge) .

According to the alternative illustrated in Figures 34, 35 and 36, the two jaws 27, opposite and coupled to each seat 16 of the manufacturing drum 13, have two respective teeth 128 which have the function of holding a corresponding sealing ring 7 inside the seat 16 itself; for this purpose, the two opposite teeth 128 are arranged on the top of the corresponding jaws 27 and protrude from the corresponding jaws 27 towards the inside (i.e. towards the centre of the seat 16) so that, when the two jaws 27 are arranged in the gripping position (illustrated in the two seats 16 to the right in Figure 34 and illustrated in Figure 35), the two teeth 128 hold, from the top, the sealing ring 7 inside the seat 16 (thus preventing the corresponding sealing ring 7 from escaping) . In other words, when the two jaws 27 are arranged in the holding position (illustrated in the two seats 16 on the right in Figure 34 and illustrated in Figure 35) , the two teeth 128 close (plug) the seat 16 at the top, thus preventing the sealing ring 7 from escaping from the seat 16 and therefore holding the sealing ring 7, from the top, inside the seat 16.

In other words, it has been noted that during the rotation movement of the manufacturing drum 13 around the rotation axis 14, the accelerations/decelerations to which the sealing rings 7 are subjected between the feeding station S5 (in which the sealing rings 7 are resting on the corresponding tubular casings 2 housed in the seats 16 of the manufacturing drum 13) and the corresponding welding station S6 (in which the sealing rings 7 are welded to the corresponding tubular casings 2 housed in the seats 16 of the manufacturing drum 13) may occasionally and accidentally release some sealing rings 7 from the corresponding seat 16; in order to avoid the accidental loss of the sealing rings 7 between the feeding station S5 and the corresponding welding station S6, the two jaws 27 opposite and coupled to each seat 16 of the manufacturing drum 13 are provided with two teeth 128 which prevent the escaping of the sealing ring 7 from the seat 16 itself .

In the embodiment illustrated in the attached figures, both the jaws 27 opposite and coupled to each seat 16 of the manufacturing drum 13 have a respective tooth 128; according to a different embodiment not illustrated, only one of the two jaws 27 opposite and coupled to each seat 16 of the manufacturing drum 13 has a respective tooth 128 while the other jaw 27 has no tooth 128. As previously said, the teeth 128 of the jaws 27 prevent the passage of the sealing rings 7 and also of the tubular casings 2 when the jaws 27 are in the holding position (illustrated in the two seats 16 on the right in Figure 34 and illustrated in Figure 35) ; consequently, in the feeding station S5 it is necessary to move the jaws 27 from the holding position (illustrated in the two seats 16 to the right in Figure 34 and illustrated in Figure 35) to the transfer position (illustrated in the seat 16 on the left in Figure 34 and illustrated in Figure 36) to initially allow the tubular casings 2 contained in the seats 16 to be raised towards the fingers 88 (and then towards the corresponding seats 89 containing the sealing rings 7) and subsequently allow the descent of the tubular casings 2 coupled to the corresponding sealing rings 7, again, inside the seats 16. Once the tubular casings 2 coupled to the corresponding sealing rings 7 are returned inside the seats 16, the jaws 27 are moved from the transfer position (illustrated in the seat 16 to the left in Figure 34 and illustrated in Figure 36) to the holding position (illustrated in the two seats 16 to the right in Figure 34 and illustrated in Figure 35) .

In the feeding station S5, the temporary opening of the jaws 27 (i.e. the temporary movement of the jaws 27 from the holding position to the transfer position) causes a loss of the perfect centring of the tubular casings 2 with respect to the seats 16; to overcome this drawback, the pushers 100 are shaped to impart and preserve the perfect centring of the tubular casings 2 with respect to the seats 16. In other words, the pushers 100 centre and keep the tubular casings 2 centred with respect to the seats 16 until the jaws 27 are not closed again (i.e. they are moved from the transfer position to the holding position) .

According to a possible embodiment, in the welding station S6 (in which the sealing rings 7 are welded to the corresponding tubular casings 2 housed in the seats 16 of the manufacturing drum 13) the two jaws 27 are opposite and coupled to each seat 16 of the manufacturing drum 13 are moved from the holding position (illustrated on the right in Figure 34 and illustrated in Figure 35) to the transfer position (illustrated in seat 16 to the left in Figure 34 and illustrated in Figure 36) to allow the sonotrodes 102 of the welding devices 101 to perform a complete annular seal (i.e. without interruptions for 360°) between each tubular casing 2 and the corresponding sealing ring 7 (as illustrated in Figure 36) .

According to an alternative embodiment, in the welding station S6 (wherein the sealing rings 7 are welded to the corresponding tubular casings 2 housed in the seats 16 of the manufacturing drum 13) the two jaws 27 are opposed and coupled to each seat 16 of the manufacturing drum 13 are kept in the holding position (illustrated in the two seats 16 on the right in Figure 34 and illustrated in Figure 35) and the sonotrode 102 of each welding device 101 has two recesses 129 which are arranged at the two teeth 128 and reproduce in negative the shape of the two teeth 128 themselves (as illustrated in Figure 35) . In this way, the sonotrodes 102 of the welder devices 101 perform an incomplete annular seal (i.e. interrupted in two small opposing zones at the two recesses 129) between each tubular casing 2 and the corresponding sealing ring 7.

According to a different embodiment, not illustrated, the two jaws 27 which are opposite and coupled to each seat 16 of the manufacturing drum 13 have more than two (for example three, four or five) respective teeth 128.

The embodiments described herein can be combined without departing from the scope of the present invention.

The manufacturing machine 8 described above has numerous advantages .

Firstly, the manufacturing machine 8 described above allows to achieve high hourly productivity while ensuring a high-quality standard .

Moreover, the manufacturing machine 8 is particularly compact and allows an operator in the vicinity of the manufacturing machine 8 to reach with his/her own hands all the various parts of the manufacturing machine 8 without having to perform unnatural movements.

Finally, the manufacturing machine 8 is relatively simple and inexpensive to manufacture.