Abstract: The method is designed to supply the motor with chopped voltage pulses of varying durations as a function of the load conditions and of the supply voltage. The chopped voltage pulse is composed of a plurality of partial pulses of predetermined durations T1, T2, and T3. The feeding circuit comprises a detector of a condition of extreme load defined by k1.multidot.T4<k2.multidot.T5, wherein k1 and k2 are constants, T4 is an interval separating T1 and T2, and T5 is an interval separating T2 and the first pulse T3.

Abstract: An inductive proximity sensor determines if a metallic object is in close proximity. An inductor is placed near the object. Several switches control the direction of the voltage passing through the inductor. During a first time period, the voltage flows through the inductor to induce a magnetic field in the object. During the second time period, the voltage is reversed in the inductor to quickly eliminate any current in the inductor. The decaying magnetic field in the object induces a voltage in the inductor which is measured during a third time period and compared to a reference value to determine the proximity of the object to the sensor.

Abstract: The driving device comprises two single-phase stepping motors (1, 2), each having a different preferential direction of rotation. The bidirectional drive is achieved by selectively feeding one or the other of the two motors.

Abstract: Method of supplying power to a single phase step motor of a time-piece, adapted to provide the motor with chopped voltage pulses of time-period T.sub.6 variable with respect to the load conditions and to the supply voltage of the motor, characterized in that each said impulsion of chopped voltage is composed of a sequence of elementary pulses of the same polarity and of a constant duration T.sub.4, and in that the durations T.sub.5i separating the said elementary voltage pulses vary according to load conditions and according to the supply voltage of the motor variable with respect to the load conditions and to the supply voltage of the motor.The invention finds a field of application in motors for time-pieces.

Abstract: The method and circuit are particularly suitable for use in timepieces and are adapted to supply the motor with chopped-voltage pulses of variable durations as a function of the load conditions of the motor. A chopped pulse of variable duration T.sub.7 is composed of a partial pulse T.sub.4 of fixed duration and of a constant number of partial pulses T.sub.6i of variable duration, spaced by intervals T.sub.5i which are themselves determined by the duration of current drop between the preceding peak and a reference value. The durations T.sub.6i are proportional to the intervals T.sub.5i.

Abstract: A multipolar rotor (11) is magnetized axially and comprises, in one of its faces situated opposite two pole pieces (1 and 2), alternate north and south poles distributed along its periphery. Each of the pole pieces has a concave inside rim provided with teeth (5) separated by interposed zones (6). A core (3), on which a coil (4) is mounted, magnetically couples the pole pieces to the coil. The pitch .alpha.s of the teeth of the pole pieces is different from the pitch .alpha.r of the poles of the rotor.