ELECTRONICALLY CONTROLLED TIMEPIECE

摘要

PURPOSE: To avoid the lowering of merchandise value of a timepiece due to inaccuracy of time and prolong the time of maintaining accuracy by using a capacitor for smoothing which has capacitance in a specific range. CONSTITUTION: The electromotive force induced by the rotation of a motor 3 is temporarily stored in a smoothing capacitor 4, IC11 and quartz oscillator 10 is driven with the stored power, and the rotation periods of hands 12 and the motor 3 is controlled by regulating the current flowing in the coil of the motor 3. The relation among the consuming current of the IC11 and the quartz oscillator 10, ih, the rotation period of the motor 3, th, voltage displacement of the capacitor, ΔVc, and the minimum capacity of the capacitor 4, Cmin, is regarded as Cmin=ihXth/ΔVc. Also, the relation among the current for initially charging the capacitor 4, i0, the time necessary for initial charge, t0, operation voltage of the IC, Vic, and the maximum capacity of the capacitor 4, Cmax, is regarded as Cmax=i0Xt0/Vic. A capacitor with a capacitance C satisfying the relation, Cmin