An electronic timepiece having a reversible stepping motor to actuate time-indicating hands to provide a time display, which comprises a driver circuit to produce driving current pulses composed of compound pulses appearing each time unit. A rotor of the stepping motor rotates a plurality of steps during each time unit to cause one of the time-indicating hands to advance through unequal intervals to provide a modulated display.
An electronic timepiece having time indicating hands driven by a stepping motor, means for detecting an internal condition such as battery voltage, pulse generating means for generating one or more pulses which are added to the time unit signal pulses applied to the stepping motor if the detected condition changes, and an indication disk which is periodically rotated by the stepping motor and which displays a pattern through a viewing aperture which varies depending upon whether additional pulses have been applied to the stepping motor or not.
In an electronic watch having a stepping motor, a battery voltage detecting circuit, a rotation detecting circuit for indicating rotation or non-rotation of the stepping motor and a motor driving power control circuit for applying a higher power drive pulse to the motor than a normal drive pulse upon detection of non-rotation, the operation of the rotation detecting circuit is inhibited upon indication of a low battery voltage condition and the motor is driven continuously with the higher power drive pulses for the extent of the battery low voltage condition. In this way, the electronic watch can be operated stably when the battery is at the end of its life and operated with lower power consumption during the time when the battery is operated at full voltage.
An electronic timepiece including a dividing circuit for developing different output pulse signals having different respective pulse repetition rates, a stepping motor and a drive circuit responsive to control signals for driving the stepping motor at a normal rate and for applying a correction pulse to the stepping motor according to the control signals. A pulse combining circuit combines the different output pulse signals from the dividing circuit for generating control signals and for applying the control signals to the drive circuit. The pulse combining circuit normally generates a control signal effective to drive the stepping motor at a normal rate, and the pulse combining circuit is responsive to a correction signal to control the drive circuit to apply a corrective pulse to the stepping motor. A detection circuit detects rotation and non-rotation of the stepping motor rotor and generates a detection voltage signal indicative of the state of rotation of the rotor. A voltage comparing circuit compares the detection voltage signal with a standard voltage value and applies a correction signal to the pulse combining circuit when non-rotation of the stepping rotor is detected after a drive pulse is applied to the stepping motor.
A drive mechanism for an additional mechanism of an electronic timepiece having a time-keeping system driven by a reversible stepping motor, in which an auxiliary driving source is arranged to accumulate energy utilizing a drive power transmitted from a time-keeping system for driving additional mechanism, and locking means maintains the energy stored in the auxiliary driving source.
In an electronic watch having an oscillator for producing a time base signal and stepping motor, drive pulses are produced for normally driving the motor under normal load conditions. The rotation and non-rotation of the motor in response to the last drive pulse is detected in response to a detecting pulse, and if non-rotation has been detected, a predetermined plurality of correction pulses are applied to the motor for driving same, the correction pulses being sufficient to drive the motor under a high torque loading. In this way, power consumption is decreased since a high power driving is saved only for high torque loading conditions.