DISPOSITIF DELIVRANT DES INFORMATIONS DEPENDANT DE LA POSITION D'UN ORGANE ROTATIF ENTRAINE PAR UN MOTEUR PAS A PAS

• Main Author: JEAN-CLAUDE BERNEY
• Format: Patent
• Language: French
• Subjects: CONTROL OR REGULATING SYSTEMS IN GENERAL; CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORSOR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; ELECTROMECHANICAL CLOCKS OR WATCHES; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; GENERATION; HOROLOGY; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS ORELEMENTS; PHYSICS; REGULATING

The device comprises a stepper motor (20, 21, 22) controlling, through intermediate wheelwork, a wheel (23) carrying at least one soft-iron cam (24) of triangular shape. On each wheel revolution, this cam passes in front of a fixed permanent magnet (25) which exerts a force of attraction on the cam. In a first phase, the attraction acts in the direction of motion of the wheel (23), this being equivalent to a reduction in the load of the motor, hence to a reduction in the time taken by the rotor (20) to perform its step. Then, when the cam moves past the magnet, the attraction acts in the direction opposite to the rotation of the wheel, this tending to increase the time taken by the rotor to perform its step. An electronic circuit detects these variations in duration of the steps of the rotor and delivers information characterising the position of the cam with respect to the magnet.