Patent · US Expired

Step motor particularly for electronic timepieces

US4518884A · kind A · utility

3Cited by
3References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 20, 1984
Grant dateMay 21, 1985
Priority date
Expiry dateJan 20, 2004

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02K37/16
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The invention relates to a step motor particularly for an electronic timepiece, comprising a stator whose two free ends constitute two pole pieces 4, 5, delimiting therebetween an air-gap 6 in which is accommodated the rotor 2. Each pole piece is provided with a recess 8 of cylindrical shape so that the axis of each cylinder is parallel with the axis of rotation Ar of the rotor 2. The two axes of the said cylinders are shifted from one another by a value comprised between 80.mu. and 200.mu. in a direction perpendicular to the plane P defined by the axis of rotation Ar of the rotor 2 and the main direction of the flux 13 generated by an exciting coil associated with the stator. The radii of the rotor 2 and the stator 3 are in the order of about 800.mu. and 1500.mu. respectively.

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