Patent ID: 11929640
Assignee: SEIKO INSTRUMENTS INC.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 0:
1. A stator for a timepiece movement, comprising:
a stator plate having a first surface and a second surface opposite to the first surface, wherein the stator plate is made with magnetic material and has a circular hole for holding a rotor in the circular hole; and
two non-magnetic regions formed around the circular hole at a 180-degree interval between the circular hole and respective peripheries of the stator plate adjacent to the circular hole, wherein the two non-magnetic regions include chromium at a weight ratio of 15 wt % or more that is heat-diffused into the stator plate from the first surface of the stator plate in such a manner that the two non-magnetic regions each have a width that becomes progressively narrower from the first surface of the stator plate toward the second surface thereof, wherein the two non-magnetic regions each have a chromium bulge protruding from the first surface of the stator plate.