A quartz controlled timekeeping device such as a chronometer or watch comprises a high frequency quartz oscillator which is coupled to a divider which reduces the quartz frequency to the required output frequency. The divider output is connected to a polarity changing driver which energizes a polarized motor. The driver changes the polarity of the driving current after every driving impulse and drives the rotor coil of the motor between alternate positions thereby driving the index system directly with quartz accuracy. A magnetic blocking system effectively blocks the indexing system when the motor is not operating but releases with a driving current impulse.
An electrical swing mechanism having a drive device with a rotor and a stator. The drive device carries out self-returning reciprocation with a rotation angle of the rotor. An intermittent drive transmission device transmits the rotation of the drive device to a utilization mechanism. An electric source unit is used for exciting the stator with a pulse current. The drive device has a rotor which is magnetized so that the same poles are formed on a diametral line intersecting the rotation axis thereof and a magnetization angle between different poles is 2 .alpha., and a stator whose magnetic pole angle .beta. is larger than said magnetization angle 2 .alpha.. The intermittent drive transmission device comprises a cut disk member having a ratchet pawl and is reciprocated by the drive device. A ratchet plate member having ratchet teeth are moved one pitch by one pitch by the ratchet pawl. The reset mechanism comprises a release lever for disengaging the ratchet pawl from the ratchet teeth and a correcting gear for turning the release lever.
An advertising display including a display object, a motor connected to the display object for rotating the object about a rotation axis, and a control circuit coupled to the motor. The control circuit includes a direct current energy source, and an oscillator connected to the energy source for generating a predetermined series of regularly timed energy pulses having a selected frequency and duty cycle to cause excitation of the motor in response to the energy pulses.
