Patent · US Expired

Low power synchronous motor and line cord therefor

US3988639A · kind A · utility

10Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 5, 1975
Grant dateOct 26, 1976
Priority date
Expiry dateSep 5, 1995

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H9/02
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A low power synchronous motor is disclosed having a rotor including a pair of rotor discs between which is sandwiched a permanent magnet which is polarized such that one of the rotor discs is a north pole and the other is a south pole. The stator includes an energizing winding having a core passing therethrough. A pair of complementary stator plates are secured at each end of the energizing winding to the core and are bent at right angles to form a copolanar stator air gap portion. The coplanar portion of the stator has a notched, circular air gap into which the rotor is positioned. The flat stator plates provide for easy assembly of the motor in a clock movement. The electrical energy coupled to the energizing winding is attenuated by means of a pair of impedance elements connected in series with the energizing winding and situated in the plug of the energizing circuit. The impedance elements reduce the current flow into the clock and hence prevent the possibility of a hazardous shock to someone coming in contact with an exposed wire.

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