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

Claim 3:
4. A method for manufacturing a timepiece movement, comprising:
providing a base plate made of magnetic material, the base plate having a first surface and a second surface opposite to the first surface;
applying chromium on the first surface of the base plate; irradiating a laser on the chromium applied on the base plate toward the first surface of the base plate to create a non-magnetic region inside the base plate in such a manner that the non-magnetic region has a width that becomes progressively narrower from the first surface of the base plate toward the second surface thereof;
pressing the base plate to form a stator plate that has a circular hole for accommodating a rotor, wherein the stator plate has two non-magnetic regions arranged around the circular hole at a 180-degree interval between the circular hole and two peripheries of the stator plate adjacent to the circular hole, and the two non-magnetic regions are formed with bulges protruding from the first surface of the stator plate;
providing a main plate in which at least one recessed space is formed; and
fixing the stator plate onto the main plate so that the first surface of the stator plate faces the main plate, wherein the bulges of the two non-magnetic regions are accommodated in the at least one recessed space formed in the main plate.