US 4,760,564 A · Analog electronic timepiece with charging function

Abstract

A timepiece has a stepping motor for intermittently rotating hands to indicate the time, a solar cell for temporarily generating electric charge and capacitors for storing the generated electric charge to supply an operating voltage. A drive circuit repeatedly applies a combination of first and second consecutive driving pulses having electric powers proportional to the operating voltage to the stepping motor, while a detector detects the operating voltage. A control circuit is connected between the drive circuit and the detector for controlling the detector to effect the operating voltage detection after the application of the first driving pulse and before the application of the following second driving pulse. When decrease of the operating voltage is detected after the application of the first driving pulse, the operating voltage is increased before the application of the following second driving pulse so as to ensure the rotation of the hands.

Claims13

Dependent claims

An analog electronic timepiece with charging function comprising:

a stepping motor;
an electric energy generating means for generating electric energy;
a plurality of capacitor means for accumulating the electric energy fed from the electric energy generating means;
a voltage detector circuit means for detecting terminal voltages of said plurality of capacitor means;
a driving pulse generator circuit means for applying a plurality of driving pulses to the step motor, said plurality of driving pulses including pulses generated at a relatively short time interval and pulses generated at a relatively long time interval;
and
a voltage detecting timing generator circuit means for determining a detection timing of said voltage detector circuit for the voltage detection to be carried out during the short time interval.

4 more elements

A timepiece comprising:

a hand;
a stepping motor for intermittently rotating the hand to indicate the time;
generating means for temporarily generating electric charge;
storing means for storing the generated electric charge to supply an operating voltage effective to operate the timepiece;
drive means for repeatedly applying a combination of first and second consecutive driving pulses having electric powers proportional to the operating voltage to the stepping motor to thereby effect the intermittent rotation of the hand;
detecting means for detecting the operating voltage;
controlling means connected between the drive means and the detecting means for controlling the detecting means to effect the operating voltage detection after the application of the first driving pulse and before the application of the following second driving pulse;
and increasing means provided in the storing means and operative when decrease of the operating voltage is detected after the application of the first driving pulse for increasing the operating voltage before the application of the following second driving pulse so as to ensure the rotation of the hand by the combination of the first and second driving pulses.

5 more elements

Dependencies are inferred from the claim text.

Analog electronic timepiece with charging function

Life of this patent

Analog electronic timepiece with charging function

Life of this patent

Abstract

Claims13