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:
Jun. 29, 1976
Filed:
Jul. 09, 1974
Applicant:
Inventors:
Igor Scherrer, Colombier, CH;
Pierre Hersberger, Neuchatel, CH;
Assignee:
Ebarches S.A., Neuchatel, CH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G04C / ; H03F / ;
U.S. Cl.
CPC ...
58 2 / ; 331183 ;
Abstract
A device for maintaining constant the amplitude of the oscillation of an electro-magnetically driven balance wheel of a timepiece, whereby a first voltage is generated of an amplitude proportional to the amplitude of oscillation of the wheel. This is compared with a reference voltage and a signal is derived corresponding in amplitude and sign with the difference. This signal is then used to control the application of driving pulses to the balance wheel. The said driving pulses are preferably much shorter than one half-period of the balance wheel.