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:
Mar. 04, 1980
Filed:
Aug. 25, 1978
Applicant:
Inventor:
Shigeru Kogure, Suwa, JP;
Assignee:
Kabushiki Kaisha Suwa Seikosha, Suwa, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
310370 ; 310312 ;
Abstract
A conventional tuning fork type quartz crystal resonator has mainly two vibration modes. They are fundamental vibration mode and overtone having the resonance frequency six times as much as the frequency of fundamental vibration. These two vibration modes have similar high quality factors. When this resonator is put to practical use, there are instances where it oscillates in undesirable mode of vibration. Accordingly, in this invention, concave portions are provided at the tops of resonator in order to prevent it. It is the most effective in case that concave portions are provided in the region of 0.65 to 0.85 from roots of arms.