Electronic watch

Claim 2

In an analog electronic timepiece of the type having a stepping motor comprised of a stator, a drive coil wound on the stator, and a rotor rotationally driven in response to pulses applied to the drive coil: an oscillator circuit for generating high frequency signals suitable as a time standard; a frequency dividing circuit receptive of the high frequency signals for frequency-dividing the same into lower frequency time signals; a pulse combining circuit receptive of the lower frequency time signals for combining the same to produce normal drive pulses and correcting drive pulses having a greater effective power than the normal drive pulses for applying the same to the motor drive coil for driving said stepping motor; detecting circuit means operative after each normal drive pulse is applied to the motor drive coil and at a time non-coincident with the application of each normal drive pulse for detecting a non-rotated condition of the motor rotor; and means controlled by said detecting circuit means for applying a correcting drive pulse to the motor drive coil before the next normal drive pulse is applied thereto in response to detection of a non-rotated condition of the motor rotor by said detecting circuit means.

Claim 3

An analog electronic timepiece according to claim 1, wherein said detecting circuit means includes means for detecting the non-rotated condition of the motor rotor by detecting the difference in inductance of the motor drive coil between rotated and non-rotated conditions of the motor rotor.

Claim 4

An analog electronic timepiece according to claim 2; wherein said detecting circuit means comprises a passive detecting element, a switching element and a binary logic element; means connecting said passive detecting element in series with the motor drive coil and in parallel with said switching element; and means connecting the input of said binary logic element to said passive detecting element.

Claim 5

An analog electronic timepiece according to claim 3; wherein said passive detecting element comprises a resistor.

Claim 6

An analog electronic timepiece according to claim 3; wherein said switching element comprises an MOSFET.

Claim 7

An analog electronic timepiece according to claim 1; wherein the detecting means comprises means operative only during detecting periods for detecting the non-rotated condition of the motor rotor, the detecting periods being non-coincident with and following the periods during which the normal drive pulses are applied to the motor drive coil.

Claim 8

An analog electronic timepiece according to claim 6; wherein the detecting means includes a passive detecting element; and means for electrically connecting the passive detecting element in series with the motor drive coil during the detecting periods.

Claim 9

In a battery-powered analog electronic timepiece of the type having a stepping motor comprised of a stator, a drive coil wound on the stator, and a rotor rotationally driven in stepwise manner in response to pulses applied to the drive coil: an oscillator circuit for generating high frequency signals suitable as a time standard; a frequency dividing circuit receptive of the high frequency signals for frequency-dividing the same into lower frequency time signals; a pulse combining circuit receptive of the lower frequency time signals for developing therefrom a succession of normal drive pulses having a given pulse period and a given effective power effective to develop the torque needed to rotationally drive the motor rotor when the normal drive pulses are applied to the motor drive coil under relatively low load timepiece operating conditions and a succession of correcting drive pulses separate from the normal drive pulses and having the same given pulse period though a greater effective power than the normal drive pulses and effective to develop the higher torque needed to rotationally drive the motor rotor when the correcting drive pulses are applied to the motor drive coil under higher load timepiece operating conditions in which the normal drive pulses are ineffective to rotationally drive the motor rotor; and motor control circuit means coacting with said pulse combining circuit for applying drive pulses to the motor drive coil in such manner to reduce overall battery power consumption by applying successive normal drive pulses to the motor drive coil whenever the immediately preceding normal drive pulse effected stepwise advancement of the motor rotor and otherwise applying, within the same pulse period as the normal drive pulse which failed to effect stepwise advancement, a correcting drive pulse to the motor drive coil before applying thereto another normal drive pulse to effect stepwise advancement of the motor rotor thereby conserving battery power by using the normal drive pulses of lesser effective power whenever possible to drive the motor rotor and using the correcting drive pulses of greater effective power only when the normal drive pulses are ineffective to drive the motor rotor.

Claim 10

In a battery-powered analog electronic timepiece of the type having a stepping motor comprised of a stator, a drive coil wound on the stator, and a rotor rotationally driven in stepwise manner in response to pulses applied to the drive coil: an oscillator circuit for generating high frequency signals suitable as a time standard; a frequency dividing circuit receptive of the high frequency signals for frequency-dividing the same into lower frequency time signals; a pulse combining circuit receptive of the lower frequency time signals for developing therefrom a succession of normal drive pulses having a given pulse period and a given effective power effective to develop the torque needed to rotationally drive the motor rotor when the normal drive pulses are applied to the motor drive coil under relatively low load timepiece operating conditions and a succession of correcting drive pulses separate from the normal drive pulses and having the same given pulse period though a greater effective power than the normal drive pulses and effective to develop the higher torque needed to rotationally drive the motor rotor when the correcting drive pulses are applied to the motor drive coil under higher load timepiece operating conditions in which the normal drive pulses are ineffective to rotationally drive the motor rotor; and motor control circuit means coacting with said pulse combining circuit for applying drive pulses to the motor drive coil in such manner to reduce overall battery power consumption by applying successive normal drive pulses to the motor drive coil whenever the immediately preceding normal drive pulse effected stepwise advancement of the motor rotor and otherwise applying, within the same pulse period as the normal drive pulse which failed to effect stepwise advancement, a correcting drive pulse to the motor drive coil before applying thereto another normal drive pulse to effect stepwise advancement of the motor rotor thereby conserving battery power by using the normal drive pulses of lesser effective power whenever possible to drive the motor rotor and using the correcting drive pulses of greater effective power only when the normal drive pulses are ineffective to drive the motor rotor.

Claim 11

A battery-powered analog electronic timepiece according to claim 18; wherein said motor control circuit means includes detecting circuit means for detecting, after application of each normal drive pulse to the motor drive coil, whenever a normal drive pulse fails to effect stepwise advancement of the motor rotor, and means responsive to such detection for applying a correcting drive pulse to the motor drive coil before the next normal drive pulse is applied thereto.

Claim 12

A battery-powered analog electronic timepiece according to claim 8 or 9; wherein said detecting circuit means includes means for detecting failure of the motor rotor to undergo stepwise advancement by detecting the difference in inductance of the motor drive coil between advanced and non-advanced states of the motor rotor.

Claim 13

A battery-powered analog electronic timepiece according to claim 12; wherein said pulse combining circuit includes means for developing normal drive pulses and correcting drive pulses of constant pulse width under all timepiece operating conditions.

Claim 14

A battery-powered analog electronic timepiece according to claim 8; wherein the detecting circuit means comprises means operative only during detecting periods for detecting the non-rotated condition of the motor rotor, the detecting periods being non-coincident with and following the periods during which the normal drive pulses are applied to the motor drive coil.

Claim 15

A battery-powered analog electronic timepiece according to claim 12; wherein the detecting circuit means includes a passive detecting element; and means for electrically connecting the passive detecting element in series with the motor drive coil during the detecting periods.

Claim 16

An analog electronic timepiece according to claim 1, 2, 8 or 9; wherein said pulse combining circuit includes means for developing normal drive pulses having a given pulse width and correcting drive pulses having a longer pulse width than the normal drive pulses.