System for making-up steps lost by the motor of a time-piece
AssigneeEbauches Electroniques S.A.
InventorBernard Maire
Life of this patent
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Abstract
The present invention concerns a time-piece comprising a system for detecting the non-rotation of a stepping motor and for making-up lost steps. The detection system comprises a device for measuring the current delivered to the motor, the logic level of the measured signal being used for controlling a correction circuit delivering additional pulses to the stepping motor. The measuring device comprises a short duration measuring pulse generator, a reference signal source, and a comparator having an output which controls the correction circuit.
Claims8
A system for making-up steps lost by a stepping motor of a timepiece, comprising:
- means for providing a time base;
- frequency divider means coupled to said time base means;
- means connected to said frequency divider means for providing driving pulses to the stepping motor;
- means coupled to said driving pulses means and to said frequency divider means for measuring the value of the current in the motor at a predetermined time after the leading edge of each of said driving pulses;
- comparator means coupled to said current measuring means for comparing said measured value of said current in the motor with a predetermined value of reference, said comparator means producing a pulse signalling the non-rotation of the motor when said measured value of said current exceeds said value of reference;
- and
- correcting means coupled to said comparator means and to said driving pulses means for delivering in response to said signalling pulse at least one additional correcting pulse to said motor through said driving pulses means.
Dependencies are inferred from the claim text.