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Machine translation
1. (WO1980002070) STRIP CHART RECORDER WITH A DIFFERENTIAL CAPACITOR SERVING AS POSITION SENSOR IN A POSITION SERVO FOR THE RECORDING PEN
Latest bibliographic data on file with the International Bureau   

Pub. No.:    WO/1980/002070    International Application No.:    PCT/DK1980/000017
Publication Date: 02.10.1980 International Filing Date: 21.03.1980
IPC:
G01D 5/241 (2006.01), G01R 17/06 (2006.01)
Applicants:
Inventors:
Priority Data:
1171/79 22.03.1979 DK
Title (EN) STRIP CHART RECORDER WITH A DIFFERENTIAL CAPACITOR SERVING AS POSITION SENSOR IN A POSITION SERVO FOR THE RECORDING PEN
(FR) ENREGISTREUR GRAPHIQUE A BANDE AYANT UN CONDENSATEUR DIFFERENTIEL SERVANT DE CAPTEUR DE POSITION DANS UN SERVO DE POSITION DE LA PLUME D"ENREGISTREMENT
Abstract: front page image
(EN)Strip chart recorders in which the curve is recorded by a rotatable pen (11) which traces the curve in a line of contact (14) which is a generator of a supporting roller (15), suffer from a plotting error inasmuch as the ordinate of the curve, which should be proportional to the angle of deflection v of the pen, is in fact proportional to the tangent of the said angle. This plotting error, which makes it impossible to carry out measurements on the curve, can be compensated by incorporating in the position servo, which serves to overcome frictional losses in the recorder, a position sensor in the form of a differential capacitor (20, 22, 23) whose differential capacitance as a function of the angle of deflection v of the pen is proportional to the tangent of v. In one embodiment this is achieved in that the moving plate (20) and the fixed plates (22, 23) of the differential capacitor are each bounded by a set of parallel lines (21, and 24, 25), and that the differential capacitor, when in its mid position, displays mirror symmetry about a plane perpendicular to the plates and passing through a zero line (17).
(FR)Les enregistreurs graphiques a bande dans lesquels la courbe est enregistree par une plume rotative (11) qui trace la courbe suivant une ligne de contact (14) qui est la generatrice d"un rouleau de support (15) souffrent d"une erreur de trace dans la mesure ou l"ordonnee de la courbe, qui devrait etre proportionnelle a l"angle de deflexion v de la plume, est en fait proportionnelle a la tangente de cet angle. Cette erreur de trace, qui rend impossible les mesures sur la courbe, peut etre compensee en incorporant dans le servo de position, qui sert a vaincre les pertes par frottement dans l"enregistreur, un capteur de position sous forme d"un condensateur differentiel (20, 22, 23) dont la capacite differentielle, fonction de l"angle de deflexion v de la plume, est proportionnelle a la tangente de v. Dans un mode de realisation, ceci est obtenu par le fait que la plaque mobile (20) et les plaques fixes (22 et 23) du condensateur differentiel sont chacune d"elles delimitee par un jeu de lignes paralleles (21, et 24, 25), et que le condensateur differentiel, lorsqu"il se trouve dans sa position moyenne, presente une symetrie de reflexion autour d"un plan perpenticulaire aux plaquets et passant au travers d"une ligne zero (17).
Designated States:
Publication Language: English (EN)
Filing Language: English (EN)