Patent · US Expired

Stator assembly for a timepiece stepping motor

US5059840A · kind A · utility

3Cited by
7References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 25, 1991
Grant dateOct 22, 1991
Priority date
Expiry dateJan 25, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02K37/16
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Briefly stated, the invention comprises an improved stepping motor and method of making it including locating it in the timepiece frame, the stepping motor including a rotor and a stator. A flat magnetizable stator member defines a central opening with diametrically opposed narrow sections on either side of the opening, a non-magnetic bushing disposed in the opening and secured to the surface of the stator member. The bushing has diametrically opposed cut-out portions aligned with the narrow sections. The narrow sections are severed to separate the stator into two pole shoes which are retained in position by the bushing. The severing is preferably by laser, but may includes sawing or other severing methods. The pole shoes of the stator member are then attached to the timepiece frame plate. The stepping motor rotor is journalled in bores formed in the frame and bushing.

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