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:
Apr. 28, 1981
Filed:
Oct. 16, 1979
Hiro Fujita, Tokorozawa, JP;
Akira Tsuzuki, Tokorozawa, JP;
Citizen Watch Co., Ltd., Tokyo, JP;
Abstract
In an electronic timepiece, a system for producing a unit time signal with a high degree of frequency stability, composed of a low frequency oscillator, a high frequency oscillator of a high degree of frequency stability which is activated only during periodic short intervals, and means for producing a timebase signal which is an exact integral submultiple in frequency of the high frequency oscillator signal, by modifying the output signal from the low frequency oscillator on the basis of periodically recurring phase coincidence between the high and low frequency oscillator signals. Information on this phase variation is stored in digital form, and is utilized to correct the low frequency signal during periods when the high frequency oscillator is inactivated.