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:
Aug. 04, 2015
Filed:
Mar. 27, 2014
Nihon Dempa Kogyo Co., Ltd., Tokyo, JP;
Kazuo Akaike, Saitama, JP;
Kaoru Kobayashi, Saitama, JP;
NIHON DEMPA KOGYO CO., LTD., Tokyo, JP;
Abstract
A crystal oscillator includes: an oscillation circuit; first and second oscillation circuits connected to first and second temperature detection crystal units, respectively; a heating portion configured to constantly maintain an ambient temperature; a frequency difference detection portion that obtains, as a temperature detection value, '{(f−f)/f}−{(f−f)/f}', where 'f' and “f” denote oscillation frequencies of the first and second oscillation circuits, respectively, and “f” and “f” denote oscillation frequencies of the first and second oscillation circuits, respectively, at a reference temperature; an accumulator that accumulates the temperature detection value; a rounding processing portion that performs rounding for the temperature detection value accumulated in the accumulator depending on a rounding factor designated independently from the accumulation number; and a heating control portion that controls power supplied to the heating portion based on the temperature detection value subjected to the rounding in the rounding processing portion.