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1. (WO1979000932) WINDINGS ARRANGEMENTS
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Winding Arrangements

TECHNICAL FIELD OF THE INVENTION
This invention relates to a winding arrangement, and has an important application to winding arrangements such as can he used on yachts or other sailing vessels to shorten foresail sheets.

BACKGROUND ART
Sailing techniques often require the rapi-d shortening of foresail sheets and, in this operation, as a fore-sail sheet is shortened, the resistance to further shortening is increased to such an extent that even very strong people are not always ahle to sheet the foresail in as far as they would like, even with the most up-to-date hand-operated, geared sheet winches.

One way of alleviating this prohlem is to provide each sheet winch with an electric motor which can he driven from an electric storage hattery carried hy the yacht. However, this involves the use of relatively expensive and heavy storage hatteries, particularly if the elec-trie motors are designed to ahsorh the large amounts of power necessary to rapidly shorten the foresail-sheets subject to relatively high tension. In addition, the drain on the electric storage hatteries presents a serious safety hazard in that electric storage
hatteries in yachts are normally provided for the operation of electronic apparatus such as radio
telephone and navigation equipment which are vital in an emergency. It is for this reason that the yachtsmen ar-fe reluctant to run the risk of overloading their electric storage hatteries.

DISCLOSURE OF THE INVENTION
An ohject of this invention is to provide a hand-operated winch with which it is possihle to avoid the physical drudgery involved in the use of conventional hand-operated sheet winches without having to rely on the expenditure of energy drawn from an electric
storage hattery.

According to the present invention a winding arrangement comprises a winch drum, a manually operated
arrangement for rotating the winch drum, coupling means operahle in a first mode to connect a hydraulic pump/motor to the manually operated arrangement to act as a pump driven hy the manually operated arrangement, and operahle in a second mode to connect the hydraulic pump/motor to the winch dram to act as a motor driving the drum, and control means for changing the coupling means from the first mode to the second mode and vice versa.

It is therefore possihle, hy operating this winding arrangement in the first mode, to rotate the winch drum manually so as to wind in a sail sheet or line attached to the winch drum, and at the same time to drive the pump to charge up a hydraulic accumulator or pass hydraulic fluid to another similar winding
arrangement operating in the second mode either directly or through a hydraulic intensifier. Then when the effort required to turn the handle hecomes too great, to change to the second mode of operation to enable the stored energy of the pressurised hydraulic fluid in the accumulator, or hydraulic fluid supplied hy one or more similar winding arrangements, to drive the motor and rotate the winch.

to W Preferably, the part of the coupling means changed hy
the control means is a composite arrangement comprising both mechanical couplings, such as gearing, and
hydraulic couplings, such as control valves, but in
some circumstances the parts of the coupling means
changed hy the control means may be predominantly
mechanical couplings or predominantly hydraulic
couplings.

The manually operated arrangement may be arranged to
be rotated to rotate the winch drum, and the coupling means may be arranged to he operable in the first mode when the manually operated arrangement is rotated in
either direction.

Embodiments of the invention will now he described,
by way of example, with reference to the accompanying
drawin s.

BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic sectional side elevation of a
winding arrangement embodying the invention, shown in
section;
Figure 2 is a section taken on the line II-II in
Figure 1 looking in the direction of the arrows;
Figure 3 is a schematic diagram of a hydraulic system
such as could be used on a yacht or other sailing
vessel, having four winding arrangements in accordance with the invention;
Figure h is an end elevation of a yacht equipped with
four winding arrangements in accordance with the
invention;
Figure 5 is a plan view of the yacht shown in
Figure h ;

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., IPO - -

Figure 6 is a schematic circuit diagram of a modified form of the hydraulic system shown in Figure 3;
Figure 7 is a plan view of a yacht equipped with four modified winding arrangements in accordance with the invention;
Figure 8 is a sectional end elevation of the yacht shown in Figure 7 taken on the line VIII-VIII;
Figure 9 is a schematic diagram of the hydraulic
circuit of two of the winding arrangements shown in Figures 7 and 8;
Figure 10 is a sectional end elevation of a gear box forming part of the apparatus shown in Figure 9 taken on the line X-X;
Figure 11 is a plan view similar to Figure 7 but
showing a modified arrangement;
Figure 12 is a schematic side elevation shown in section of a further winding arrangement embodying the invention Figure 13 is a sectional plan view of the winding arrangement shown in Figure 12, taken on the line XIII-XI in Figure 12;
Figure Ik is a schematic side elevation of another winding arrangement embodying the invention;
Figure 15 is a sectional end elevation of a gear box forming part of the assembly shown in Figure I , taken on the line XV-XV in Figure 14; and
Figure 16 is a schematic diagram showing two winding arrangements as shown in Figures 12 and 13, but having a common accumulator.

*

- O BEST MODES FOR CARRYING OUT THE INVENTION
Referring in the first instance to Figures 1 and.2, the winding arrangement 1 embodying the invention includes a winch drum 2 provided with self-tailing device (not shown). A stainless steel shaft k extends internally
of the drum 2, along the central axis of the drum 2,
and is provided at its upper end with a socket 5 which receives a removable handle 6. The shaft k is journal-led for rotation within the drum 2 in a plain hearing 7 formed in a hollow tubular member 8 which extends
axially within the drum 2. The drum 2 is journalled
for rotation on the tubular member 8 by a plurality of caged needle roller bearings 16.

The shaft k is coupled to the drum 2 by a unidirectional clutch 9 comprising a plurality of spring-loaded pawls
10 housed in the drum 2 and arranged to engage with
teeth 11 on a rachet wheel 12 secured to the shaft k .
The unidirectional clutch 9 is arranged to rotate the drum 2 when the handle 6 is turned in a clockwise
direction, but not to transmit motion when the handle 6 is turned in an anti-clockwise direction. The lower
end of the shaft 4 is rotationally fast with the upper end of a drive shaft Ik of a hydraulic pump/motor 15
which can act as a pump when rotated in either direction and can act as a motor when supplied with hydraulic
fluid under pressure.

The shaft k is also coupled to the drum 2 through a
gear train 20 which includes a unidirectional clutch 21 rotatably mounted on a shaft 22 and meshing with teeth
23 provided on the lowered end of the shaft k. The
unidirectional clutch 21 is arranged to transmit motion to a gear wheel 2k to rotate it in a clockwise direction when the handle 6 is rotated in an anti-clockwise

O PI
/.. IPO direction, hut not to transmit motion to the gear wheel 24 when the handle 6 is turned in a clockwise direction. The gear-wheel 24 meshes with the ring gear 25 formed internally of the drum 2 so that the drum 2 rotates in a clockwise direction when the handle 6 is turned in an anti-clockwise direction.

Referring now also to Figure 3, the hydraulic system comprises a winding arrangement 1 as described with reference to Figures 1 and 2, in which the hydraulic pump/motor 15 is of the kind which can act as a pump when rotated in either a clockwise or an anti-clockwise direction. One side of the pump/motor 15 is connected by way of a hydraulic fluid line 26 to a hydraulic accumulator 28 and is also connected by way of a one-"way valve 29 to the other side of the pump/motor 15.
The other side of the pump/motor 15 is connected to the three-way valve 30 arranged to provide hydraulic circuits 31 and 32 respectively to and from the pump/ motors of three similar winding arrangements (not shown). The three-way valve 30 is also arranged to provide hydraulic connections to a hydraulic multiplier or intensifier 33 by way of a low pressure release valve 34 and a changeover valve 35.

The winding arrangement operates in the following manner. When the handle 6 is rotated in a clockwise direction (as seen from ahove) the pump/motor 15 acts as a pump which passes hydraulic fluid in the direction indicated hy the arrow 37 in Figure 3. The resulting flow of hydraulic fluid can be used to supply the pump/mot.r 15 of the other three winding arrangements, either directly or through the hydraulic intensifier 33, or to charge the hydraulic accumulator 28 depending on

/,, the positions of the three-way valve 30. The rotation of the handle 6 in the clockwise direction also rotates the winch drum 2 in the clockwise direction through the unidirectional clutch 9, so that the winding arrangement 1 can be utilized to simultaneously shorten a foresail sheet and to perform any of the other functions
controlled by the three-way valve 30.

The rotation of the handle 6 in the anti-clockwise
direction also rotates the winch drum 2 in the clock-wise direction, but this time through the unidirectional clutch 21, the gear wheel 24 and ring
gear 25 which form a reduction gear train. When the
handle 6 is rotated in an anti-clockwise direction
the pump/motor 15 acts as a pump which passes hydraulic fluid in the direction indicated hy the arrow 38.
The hydraulic fluid then flows to the other side of the pump/motor 15 through a non-return valve 29 so that
the arrangement behaves as a "hydraulic freewheel".
Thus the winding arrangement 1 can be utilized to
shorten a foresail sheet hy rotating the handle 6 in
the anti-clockwise direction.

When the three-way valve 30 is in the position 40
shown in full line, the pump/motor 15 can he used to
act as a pump to supply hydraulic fluid under pressure to the pump/motor of one or more of the other winding
arrangements connected to the hydraulic circuits 31.
The pump/motor of that other winding arrangement would then act as a motor to assist the operation of the
other winding arrangement. Alternatively, when the
three-κay valve 30 is in the position 40 shown in full line, pump/motor 15 can he used to act as a motor which receives hydraulic fluid under pressure from the pump/ motors of one or more of the other winding arrangements

ϋREΛ
OMPI IPO connected to the hydraulic circuits 32. The pump/motors of the other winding arrangements would then act as

- umps to assist the operation of the winding arrangement

When the three-way valve 30 is in the position 40 and the pump/motor 15 is being used as a pump, then if the pressure of the hydraulic fluid is relatively low, say less then 300 p.s.i. the hydraulic fluid flows hy way of a pipe line 42 and a non-return valve 43 to the hydraulic circuits 31 of the other winding arrangements. The pump/motors of the other winding arrangements can then act as motors to assist the operation of those other winding arrangements.

When the three-way valve 30 is in the position 40 and the flow of hydraulic fluid being pumped by the pump/ motor 15 is at a pressure above 300 p.s.i., the low pressure release valve 34 opens. The hydraulic fluid then flows hy way of pipe line 44, the position .45 of the changeover valve 35 shown in full line to the large cylinder 46 of the hydraulic intensifier 35 and moves a piston 47 along the cylinder 46. As the piston 47 approaches the upper, end of the cylinder 46 a piston rod 48 actuates an operating lever 49 of the changeover valve 35 so that it assumes the position 50 shown in dotted line. The piston 47 then returns to its original position in the cylinder 46 and continues with this reciprocating action as the piston rod repeatedly actuat the operating lever 45 from the positon shown in- full line to the position shown in dotted line and vice versa

The piston rod 48 is coupled to a piston 51 of a small cylinder 52 of the hydraulic intensifier 33 so that the piston 51 follows the reciprocating motion of the piston 47. The reciprocating motion of the piston causes hydraulic fluid from the reservoir 28 to be sucked into the cylinder 2 by way of non-return
valves 53 and 4 and to flow by way of non-return
valves 55 and 56, pipe line 57 the hydraulic circuits 31 to the pump/motors of the other winding arrangements to assist their operation. The multiplying action of the hydraulic intensifier 33, which is dependent on the ratio hetween the capacities of the cylinders 46 and 52, would typically be in the region of seven to one. A hydraulic accumulator 63 is arranged to store hydraulic fluid under pressure supplied by the small cylinder 52 of the hydraulic intensifier 33. An on/off valve 64, enables the stored hydraulic fluid to be returned to the system when required. A high pressure relief valve 58, which is connected to the reservoir 28 by way of a pipe line 59, is arranged to prevent build up of excessive pressure in the system.

When the three-way valve 30 is in the position 41
shown in dotted line the pump/motor 15 acts as a motor which receives hydraulic fluid under pressure from the pump/motors of one or more of the other winding
arrangements connected to the hydraulic circuits 32.
If the flow of hydraulic is at a relatively low pressure, say less than 300 p.s.i., the hydraulic fluid flows hy way of the pipe line 42, the non-return valve 43, the position 41 of three-way valve 15 and the pump/motor 15 to the reservoir 28. The pump/motors of the other winding arrangements then act as pumps to assist the operation of the winding arrangement 1.

When the three-way valve 30 is in the position 41 and the flow of hydraulic fluid under pressure from the pump/motors of one or more of the winding arrangements connected to the hydraulic circuits 32 is greater than 300 p.s.i., the low pressure release valve 34 opens. The hydraulic fluid then flows by way of the pipe line 44 and changeover valve 35 to the cylinder 46 of the hydraulic intensifier 33. The resulting reciprocating action of the piston 51 in the cylinder 5 causes hydraulic fluid to flow by way of non-return valves 55 and 6, pipe line 60 and position 41 of the three-way valve 30 to the pump/motor 15 of the winding arrangement 1. In this way the pump/motors of the other winding arrangement connected to the hydraulic circuits 32 can be utilized to assist the operation of the winding arrangement 1.

When the three-way valve 30 is in the position 61 shown in dotted line, a local circuit for the pump/ motor 15 is provided hy a pipe line 62. The winding arrangement can then be used as a manual arrangement without hydraulic assistance, since the local circuit acts as a "hydraulic free wheel" for hydraulic fluid which is pumped in either direction by the pump/motor 15. Thus the winding arrangement 1 may be used to rotate the winch drum 2 through the unidirectional clutch 9 by rotating the handle 6 in a clockwise direction, or may be used to rotate the winch drum 2 through the gear train 20 and unidirectional clutch 21, with the advantage of the reduction gear train, by rotating the handle 6 in an anti-clockwise direction.

As shown in Figures 4 and 5, a yacht 70 is provided with four winding arrangements 1 in accordance with the invention for sheeting-in a sheet or line 71 connected to a foresail 72 supported by a mast 73.
Depending on sailing conditions, any one of the four winding arrangements 1 can he used. Although the yacht

/to 70 is provided with other sails, these have heen omitted for the sake of clarity of illustration. Two of the winding arrangements 1 are mounted on the port side 74 and two on the starboard side 75 of the stern end 76 of the hull 77 of the yacht 70 and each winding
arrangement 1 is connected to a hydraulic system modified as shown in Figure 6.

As shown in Figure 6 the hydraulic circuit comprises a "ring main" or loop line 80 connected to the reservoir 28 and connected to pump/motor 15 of each of the four winding arrangement by a pipe line 26. A second "ring main" or loop line 81 is connected to the large cylinder 46 of the hydraulic intensifier 33 oy way of the low pressure release valve 34 and the changeover valve 35. A third "ring main" or loop line 82 is fed with hydraulic fluid at relatively high pressure, that is ahσve 300 p.s.i., from the small cylinder 5 of the hydraulic intensifier 33 Dy way of non-return valves 55 and 56.

The small cylinder 5 of the hydraulic intensifier 33 is supplied with hydraulic fluid from the loop line 80 hy way of non-return valves 53 and 54. The three-way valves 30 associated with each of the winding arrangements 1 connect the pump/motor 15 to the loop lines 80, 81 and 82. The hydraulic accumulator 63 stores hydraulic fluid under pressure so that it can he fed to the loop line 82 when required hy operating the on/off valve 64.

It will he appreciated that any one of the four winding arrangements 1 can be utilized to sheet in the foresail 72 and its operation can he remotely controlled or
assisted hy hydraulic fluid under pressure pumped by, one or more of the other winding arrangements 1. Thus when the yacht 70 is heeling over to the starboard side 75 as shown in Figure 4, either of the two winding arrangements 1 on the port side can he used to control the sheeting in of the foresail 72 without any difficult arising from the fact that the winding arrangements 1 on the starboard side are dipping almost to the water line 78. Moreover, further assistance in the operation of a winding arrangement 1 to sheet in the foresail 72 may be provided hy the hydraulic fluid store under pressure in the hydraulic accumulator 63 by operating the on/off valve 64.

Referring now to Figures 7 and 8 the yacht 103 is provided with four winding arrangements 101 for sheeting in a sheet or line 104 connected to a foresail 105 supported on a mast 106. Two of the winding arrangement are mounted on the port side 107 and two on the starboard side 108 of the stern end 109 of the hull 110.
Each winding arrangement 101 comprieses a winch drum 102 driven by a hydraulic motor 112 and control means 114 for operating the hydraulic motors 112. As shown in Figure 8f the control means 114 for each motor 112 are disposed remote from the side 107 or 108 of the stern end 109 of the hull 110 on which the motor 112 is mounted.

Thus, when the yacht 103 is heeling over the starboard side 108, as shown in Figure 1, each winding arrangement 1 on the starhoard side 108 of the yacht 103 can he operated to sheet-in the foresail 105 "by operation of the control means on the port hand side 38, without any undue difficulty arising from the fact that the winding arrangements 101 on the starboard side 108 are dipping almost to the water line 115.

As shown more clearly in Figure 7, the control means 114 for the hydraulic motor 112 on the starboard side 108 of the hull 110 is a manually-operable hydraulic pump 114. A similar pump is provided for controlling operation of the hydraulic motor 112 on the port side 107 of the hull 110, but for the sake of clarity of illustration, this additional pump has been omitted from Figure 7.

From reference to Figure 9, which is a schematic
representation of the two winding arrangements 101 on the starboard side 108 of the yacht 103 it is
clear that the hydraulic motor 112 comprises a piston-cylinder assembly 116 having a double acting piston
117 which is reciprocahle within a hydraulic cylinder 118. Connecting rods 119 and 120 extend through the opposite ends of the cylinder 118 from opposite sides of the piston 117. At their outer ends, the connecting rods 119 and 120 are respectively connected to two rack memhers 122 which are respectively reciprocahle, on operation of the piston cylinder assemhly 116, through two gear "boxes 123 which are drivingly connected to the two winding arrangements respectively. As hereinafter described, with reference to Figure 10, the gear boxes 123 are operable to drive the winch drums 102 continuou-sly in one direction as a result of reciprocating
movement of the rack members 122.

On operation of the manually-operahle hydraulic pump 114, hydraulic fluid is drawn from a sump 124 through a pipe line 125, pressurised, and then passed through a supply -iine 126 and a changeover valve 127 to a first cylinder line 128 connected to one end of the cylinder

118 so as to drive the piston 117 towards the other end of the cylinder 118. Hydraulic fluid from the other end of the cylinder 118 passes hy way of a second - 14 -

cylinder line 129, the changeover valve 127. and a discharge line 130 which returns the discharged
hydraulic fluid to the sump 124.

In order to effect return movement of the piston 117, the changeover valve 127 is operated so as to reverse the connections hetween the supply and discharge lines 126 and 130 with the first and second cylinder lines 128 and 129. This operation is achieved hy displacemen of a bi-stahle trigger 131 on the changeover valve 127 hy strikers 132 and 133 carried by opposite ends of the adjacent connecting rod 119. Thus, as shown in Figure 9, operation of the pump 114 causes the piston 117 to move towards the left until striker 132 displaces trigger 131 from one of its stahle positions to its other stahle position. This results in reversal of flow of hydraulic fluid into and out of the cylinder 118 and so the piston 117 reverses its direction of movement and moves towards the left. At the completion of this leftward movement, the other striker 133
returns the trigger 131 to its first stable position, thus causing a reversal in the flow of hydraulic fluid into and out of the cylinder 118 and a consequent reversal in the direction of movement of the piston 117.

In practice, the winding arrangements 101 on the port side 107 of the hull 110 are controlled in a completely analagous way hy apparatus which, in general, is the same as the apparatus hereinhefore described. However, it is only necessary to provide one sump 124.

s shown in Figure 10, each rack memher 122 is arranged for reciprocating movement between two clutch shafts 134 and 135 so that two toothed racks 136 and 137

^J
_ formed, respectively, on opposite edges of the rack member 122 respectively mesh with two pinions 138 and
139 which are keyed to the clutch shafts 134 and 135
respectively, so as to cause the two clutch shafts
5 134 and 135 to rotate in opposite directions. Two unidirectional clutches 140 and 141 respectively
connect the clutch shafts 134 and 135 to two coaxially aligned drive shafts 142 and 143 and are constructed
so that when each clutch shaft 134 and 135 is rotated

10 in one direction, say clockwise, when viewed from above, this clockwise movement is transmitted to the coaxially aligned shaft 142 or 143 whereas, when each clutch shaft 134 and 135 is rotated in the other direction, i.e.
anticlockwise, when viewed from above, the coaxially

15. aligned drive shaft 142 or 143 is able to rotate freely in the opposite or clockwise direction.

Thus, if the rack member 122 is moved in a direction
which causes clockwise rotation of pinion 138 and
clutch shaft 134, as viewed from above, this motion is

20 transmitted to drive shaft 142 through unidirectional clutch 140. A driving pinion 144 keyed to drive shaft
142 meshes with a driven pinion 145 which is keyed to a shaft 146 carrying a winch drum 102 so as to drive
the winch drum 102 in an anticlockwise direction.
25 During this anticlockwise movement of the winch drum
102, the pinion 139 and clutch shaft 134 are driven in an anticlockwise direction by the toothed rack 137, hut the drive shaft 143 is driven in a clockwise direction by means of a further driving pinion 147 which is keyed

30 to the drive shaft 143 and measures with the driven
pinion 145. In this case, the oppositely directed
rotations of the coaxially aligned shafts 143 and 134 are accommodated by the unidirectional clutch 141.

When the rack member 122 is moved in the opposite direction, so as to cause the pinion 139 and the clutch shaft 134 to rotate in a clockwise direction, as viewed from above, this movement is transmitted to the coaxially aligned drive shaft 143 and so the winch drum 102 continues to move in an anticlockwise
direction. In this case, the clockwise movement of the drive shaft 142 and the anticlockwise rotation of the coaxially aligned shaft 135 are accommodated hy the unidirectional clutch 140.

In the yacht 103 illustrated in Figure 11, the
apparatus illustrated in Figure 7 is modifed hy the replacement of the two pumps 114 with a single,
manually-operable, centrally disposed hydraulic pump 148, and hy the insertion of a transfer line 149 and a pressurised hydraulic fluid vessel 150 hetween the pump 148 and the supply line 13 and hy the insertion of a control valve 1 1 in a part of the supply line 136 which is remote from the starboard side 108 of the stern end 109 of the hull 110 where the winding
arrangements 101 controlled by this valve are mounted. This control valve 151 is provided with an actuating handle 152 which, "being on the control valve 151, serves as control means which are disposed remote from the starboard 108 of the stern end 109 of the hull 110, on which the winding arrangements 101 controlled hy the valve 151 are mounted. However, in alternative forms of construction, the control valve 151 may be placed in other parts of the supply line 136, hut is remotely actuated hy control means, such as an electrical switch disposed in a position such as the position occupied hy the valve 151 in the embodiment illustrated in
Figure 11.

Although not shown, for the sake of clarity of
illustration, the winding arrangements 101 mounted on the port side 107 of the stern end 109 of the hull 110 are controlled in a completely analogous way by
apparatus which, in general, is the same as the
apparatus hereinbefore described with reference to
Figure 11. However, in this case, the sump 124, the
pressurised hydraulic fluid vessel 150 and a single,
centrally mounted manually-operable hydraulic pump
148 are common to the apparatus provided for controlling the winding arrangements 101 on both sides 107 and 108 of the hull 110.

Although not specifically described with reference to the drawings, it is clear that the piston-cylinder
assemblies 21 can be provided for pneumatic operation instead of for hydraulic operation. In this case, the further modification of the apparatus hereinbefore
described merely involves the omission of the sumps 124, the inlet lines 125 and the discharge lines 130.

As the winding arrangements 101 are self-tailing,
loosening of the foresail sheet 104 can he effected
simply hy flicking the sheet 10.4 from the winch drum
102. Where the winding arrangements 101 are not
constructed as self-tailing, it is necessary to loop
the sheet around the winch drum 102 and to maintain
purchase by hand tension. In this case, loosening
of the sheet is effected merely by releasing this
hand tension.

Referring now to Figures 12 and 13, a winding
arrangement 155, embodying the present invention,
includes a winch drum 156 provided with a self-tailing device 157. A hand-driven barrel 158 extends intern-

OMPI
». IPO ally of the drum 156, along the central axis of the dru 156, and is formed with a socket 159 for receiving a removable handle i6θ (only partly shown). A first sun gear l6i is connected to a ring gear 162 formed intern-ally of the winch drum 1 hy means of first idler gears 163 and 164 and a second sun gear 165 is
connected to the ring gear 162 by means of a second idler gear 166.

As shown in Figure 12, the first sun gear l6l is connected to the barrel 158 hy means of a first unidirectional clutch so that, when the handle l6θ is rotated in a clockwise direction, as viewed from ahove, this motion is transmitted to the winch drum 156, which also rotates in a clockwise direction, hut at a lower speed. However, the handle l6θ can be turned in the opposite direction without moving the first sun gear 161. Similarly, the second sun gear 165 is connected to the first sun gear i6l by a second unidirectional clutch so that when rotated in a clockwise direction; when viewed from ahove, this motion is also transmitted to the winch drum 156 and, when the second sun gear 161 is rotated in the opposite direction, ther is no transmission of this movement. Although conventional unidirectional clutches would serve for connecting the harrel 158 and the first and second sun gears l6i and 165, it is preferred that these connectio are made hy radially extending serrations I67 formed on the engaging parts. In this case, a helical
compression spring 168 is provided so as to press the first and second sun gears i6l and 165 axially towards the barrel 158.

On rotation of the winch drum 156, a second idler gear l66 drives second sun gear I65 in an anticlockwise direction as viewed from above. A shaft 169, connected to the second sun gear 165, therefore turns a hydraulic pump/motor 170 in an anticlockwise direction so as to draw hydraulic fluid from a sump 171 of an accumulator 172 through a hydraulic fluid line 173 and pressurised hydraulic fluid is delivered through another hydraulic fluid line 174 to a pressure vessel 175 in the
accumulator 172. A control valve 176 in the lines 173 and 174 prevents flow of hydraulic fluid in the opposite direction.

When the loading on the handle 160 becomes uncomfortably high, the handle l6θ can be released and the winch drum 1 is held by means of ratchet pawls 177 engaging the ring gear, as shown in Figure 13.
Control means 178 can then he operated so as to withdraw second idler gear 166 from meshing engagement with the second sun gear 165 so as to disconnect the pump/motor 170 from the handle l6θ. At this stage, the handle i6θ may he turned further, as a result of the reduction in loading on the handle. However, regardless of whether the handle 160 is used to continue the winding of the sheet attached to the winch drum 156 or not, the control means 178 can be further operated to reverse the control valve 176, thus permitting
pressurised hydraulic fluid to flow from the pressure vessel 175 to the sump 17i through the pump/motor 170, in the opposite direction, thus turning the shaft 169 in a clockwise direction, as viewed from above. This motion is therefore transmitted through the uni-directional connection between the first and second sun gearg l6l and 165 and through the first idler gears 163 and 164 so as to continue the rotation of the winch drum 156 in its original direction. In order to terminate this final tightening of the sheet attached to the winch drum 156, it is merely necessary to reverse the control valve 176 hy operating the control means 178.

In the assembly shown in Figure 12, the hydraulic pump/motor 170 is a reversihle gear pump and the gear ratio hetween the ring gear 162 and the second sun gear 165 is chosen, together with the gear ratio
hetween the first sun gear 161 and the ring gear 162 so that the handle i6θ is able to provide sufficient torque to suit the characteristics of the pump/motor.

In the winding arrangement schematically shown in
Figure 14, the winch drum 156 and its internal gearing are constructed in the same manner as in the winding assembly 155 illusttated in Figures 12 and 13. However, in this case, the hydraulic pump/motor comprises a piston-cylinder assembly 180 having a double acting piston 181 which is reciprocahle within a hydraulic cylinder 182 hy means of a crank mechanism 183
connected to the shaft 169 extending from the second sun gear 165 of the winding arrangement. Piston rods

184 and 185 extend through opposite ends of the cylinder 182 from opposite sides of the piston 181. One of the connecting rods 184 is connected to a rack member 186 which is reciprocahle, on operation of the piston-cylinder assemhly 180, through a gear hox 187 which, as hereinafter descrihed, with reference to Figure 15, is unidirectionally connected to the shaft 169 for driving the winch drum 156 in a clockwise direction as viewed from above.

As shown in Figure 14, when the handle 160 is heing turned so as to rotate the winch drum 156 in a clockwise direction, as viewed from above a connecting rod

O Λ W 188 of the crank mechanism 183 pulls the piston 181 towards the right, thus charging the accumulatore 172 with pressurised hydraulic fluid while, at the same time, drawing low pressure hydraulic fluid from the accumulator 172 into the left hand end of the hydraulic cylinder 182.

The hydraulic fluid lines 173 and 174 connecting the cylinder 182 to the accumulator 172 pass through a control valve 176 connected to the control means 178 and through a reversing valve 188. Thus, on completion of the movement of the piston 181 towards the right, a striker 189 carried by the piston rod 185 displaces a bi-stable trigger 190 on the reversing valve 191, thus reversing the connections of the high pressure and low pressure lines 173 and 174 to the cylinder 182. As a result, further movement of the piston 181 towards the left, hy means of the crank mechanism 183 causes further charging of the accumulator 172. When the piston 181 completes its leftward motion, a striker 192 carried by the piston rod 185 returns the bi-stable trigger 190 to its initial position so that charging of the accumulator 172 continues when the piston 181 is again moved towards the right.

When it is desired to utilise the stored energy within the accumulator 172 to rotate the winch drum 156, the control means 178 are first operated so as to disconnect the forward drive hetween the handle i6θ and the crank mechanism 183 by disengaging the second idler gear 166 from the first sun gear I65. The control means IT are then operated so as to reverse the
control valve 176 so as to allow hydraulic fluid to circulate in the opposite direction.

The piston 181 is therefore reciprocated in an
analogous manner to that which is described above.
However, in this case, the piston 181 reciprocates the rack member 186.

In the gear hox 187 shown in Figure 15, the shaft 169 from the second sun gear 165 passes through a slot 193 formed in the rack member so as to follow the rack
member 186 to reciprocate between two clutch shafts
194 and 195 so that two toothed racks 196 and 197
formed, respectively, on opposite edges of the rack
member 186 respectively mesh with two pinions 198 and
199 which are keyed to the clutch shafts 194 and 195, respectively, so as to cause the two clutch shafts 194 and 195 to rotate in opposite directions. Two uni-directional clutches 200 and 201 respectively connect the clutch shafts 194 and 195 to two coaxially aligned drive shafts 202 and 203 and are constructed so that when each clutch shaft 194 and 195 is rotated in an
anticlockwise direction, when viewed from above, this anticlockwise movement is transmitted to the coaxially aligned shaft 202 or 203 whereas, when each clutch
shaft 194 and 195 is rotated in the clockwise direction, when viewed from above, the coaxially aligned drive
shaft 202 or 203 is able to rotate freely in the
opposite or anticlockwise direction.

Thus, if the rack member 186 is moved in a direction which causes anticlockwise rotation of pinion 198 and clutch shaft 194, as viewed from above, this motion
is transmitted to drive shaft 202 through unidirectional clutch 20/). A driving pinion 204 keyed to drive shaft 202 meshes with a driven pinion 205 which is connected to the shaft 169 by a right hand helical formations
206 so as to drive the second sun gear (not shown) in

OMPI WIP a clockwise direction, thus causing the drum 15 to
continue its clockwise rotation. During this clockwise movement of the winch drum 156, the pinion 199 and
clutch shaft 195 are driven in a clockwise direction
by the toothed rack 186, but the drive shaft 203 is
driven in an anticlockwise direction by means of a
further driving pinion 207 which is keyed to the drive shaft 203 and meshes with the driving pinion 205.
In this case, the oppositely directed rotations of the coaxially aligned shafts 203 and 195 are accommodated hy the unidirectional clutch 201.

When the rack member 186 is moved in the opposite
direction, so as to cause the pinion 199 and the clutch shaft 195 to rotate in an anticlockwise direction, as viewed from above, this movement is transmitted to the coaxially aligned drive shaft 203 and so the shaft 169 and the winch drum 156 continue to move in a clockwise direction. In this case, the anticlockwise movement
of the drive shaft 202 and the clockwise rotation of the coaxially aligned shaft 194 are accommodated by the
unidirectional clutch 200.

During pumping, when the second idler gear 166 connects the ring gear 162 to the second sun gear 165, the
shaft 169 rotates in an anticlockwise direction and
the right hand helical formation 206 lifts the driving pinion 205 out of engagement with the driving pinions
204 and 207, thus isolating the gear box 187.

In the arrangement shown in Figure 16, a winding
arrangement 155, as described with reference to
Figures 12 and 13, is used in conjunction with a
further winch drum and pump/motor, the pump/motor
being connected to a common accumulator 172. Thus,

OMPI in addition to the winding arrangement 155, there is provided a further winding arrangement 209 having a winch drum 210, a further central, hand-driven barrel 211 extending internally of the winch drum 210; a further first sun gear 212 connected to the further winch drum 210 for rotation with the further drum 210, at least in one direction; a further second sun gear 213 connected to the further first sun gear 212 for unidirectional rotation relative to the further first sun gear 212; a further ring gear 214 formed internally of the further winch drum 210; further first and
second idler gear means 215, 216 and 217 respectively interconnecting the further first and further second sun gears 212 and 213 with the further ring gear 214 so that, when the further drum 210 and further first sun gear 212 rotate in said one direction, the further second sun gear 213 rotates in the opposite direction; a further hydraulic pump/motor 218 in the form of a reversihle gear pump, connected to the further second sun gear 213; and two further hydraulic fluid lines 219 and 220 extend respectively from opposite sides of the further pump/motor 218 to the sump 171 and to the pressure vessel 175 of the accumulator 172, respectively.

In this arrangement, it is possible to charge the
accumulator hy rotating either or hoth of the winding arrangements 155 and 209 and so, hy this means, each winding arrangement 155 or 209 may be rotated hy-draulically hy winding a handle attached to the other winding arrangement.

Although^ in the arrangement illustrated in Figure 16, both pump/motor units are described as rotary units such as reversihle gear pumps, one or both of these units may he of different construction such as a piston-cylinder assembly.

Although reference numberals have been used in the appended Claims to improve the intelligibility of these Claims, it is expressly stated that these reference numerals should not be construed as limiting the Claims to the constructions illustrated in the accompanying drawings .