The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 30, 2025
Filed:
Jan. 13, 2022
Applicant:
Citizen Watch Co., Ltd., Tokyo, JP;
Inventors:
Yu Takyo, Nishitokyo, JP;
Yusaku Niida, Kawagoe, JP;
Takuya Shirai, Tokyo, JP;
Yosuke Abe, Fuchu, JP;
Assignee:
CITIZEN WATCH CO., LTD., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G04C 3/06 (2006.01); G04C 5/00 (2006.01); G04C 10/00 (2006.01);
U.S. Cl.
CPC ...
G04C 3/064 (2013.01); G04C 5/005 (2013.01); G04C 10/00 (2013.01);
Abstract
A mechanical timepiece includes: a hairspring; a permanent magnet; a soft magnetic core; a control circuit for performing rate adjustment based on a counter-electromotive voltage caused in a coil by a motion of the permanent magnet accompanying a forward direction motion and a reverse direction motion of the balance wheel. The permanent magnet is arranged so that, under a state in which the hairspring is brought to an equilibrium length, a direction of magnetization is directed to the first end portion side or the second end portion side.