Seiko Instruments Inc

Yoshimitsu Kurasawa

Tokuya Akase

Susumu Fujita

Joichi Miyazaki

An electronic timepiece has a thermoelectric element for generating an electromotive force in response to a temperature difference thereacross. A booster circuit boosts the electromotive force generated by the thermoelectric element. A storage mechanism stores electrical power utilizing the electromotive force boosted by the booster circuit. A power monitoring circuit monitors the electromotive force boosted by the booster circuit to detect whether the boosted electromotive force is lower than a threshold value. An oscillation circuit is driven by electrical power stored in the storage mechanism. A dividing circuit frequency-divides a signal output by the oscillation circuit. A display mechanism is driven by a display driving circuit to display time in accordance with an output signal from the dividing circuit. A display drive controlling circuit stops operation of the display driving circuit when the power monitoring circuit detects that the boosted electromotive force is lower than the threshold value.

Electronic timepiece having thermoelectric element

A center wheel & pinion of a wheel train is formed so that high load is applied to the wheel train when a minute hand stands at twelve o'clock. A pulse control circuit outputs a normal driving pulse. When a motor does not rotate by the normal driving pulse, the pulse control circuit outputs a first auxiliary driving pulse. Further, when the motor does not rotate by the first auxiliary driving pulse, the pulse control circuit outputs a second auxiliary driving pulse. The motor normally rotates by the normal driving pulse or the first auxiliary driving pulse or rotates by the second auxiliary driving pulse when the high load is applied to the wheel train, i.e., when the minute hand stands at twelve o'clock. A pointer position detecting circuit judges that the minute hand stands at twelve o'clock when it receives the P output signal from the pulse control circuit, i.e., when the second auxiliary driving pulse is outputted from the pulse control circuit.

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Chiba, Japan

Yoshimitsu Kurasawa