Small appliance driven by unidirectional single-phase synchronous motor

摘要

A small domestic appliance is driven by means of a single-phase synchronous motor (2) whose drive shaft (5) drives a load (9), the work function being independent of the direction of rotation of the motor and the operating noise and vibrations produced by the motor being dependent on the direction of rotation of the motor. In the transmisson system a unidirectional blocking device (41) forces the rotor to start in the optimum direction of rotation. In particular, the single-phase synchronous motor (2) including its transmission path to the load (9) is constructed that the optimum operating noise is obtained in that direction of rotation in which the torque exerted on the rotor (3) by the stator current becomes zero before the magnetic detent torque has become zero, when the stator coils (4d) are not energized. This has led to a stable rest position.