Patent · US Expired

Small appliance driven by unidirectional single-phase synchronous motor

US4760297A · kind A · utility

6Cited by
4References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 31, 1987
Grant dateJul 26, 1988
Priority date
Expiry dateMar 31, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T74/12
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.