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. 31, 1982
Filed:
Nov. 27, 1979
Sho Masujima, Tokyo, JP;
Shoichi Iwaya, Kasagata, JP;
TDK Electronics Co., Ltd., Tokyo, JP;
Abstract
A capacitor trimming system for a quartz-crystal oscillator in a watch and/or a clock for providing a punctual watch and/or a clock has been found. The system comprises an oscillation circuit including at least a quartz-crystal piece, a trimmer capacitor for adjusting the oscillating frequency of the quartz-crystal piece, a semiconductor electronic circuit for operating said quartz-crystal piece, and apparatus for adjusting automatically the trimmer capacitor so that the oscillating frequency becomes the same as the desired reference frequency. The trimmer capacitor comprises of at least a fixed outer trimming electrode, an inner common electrode fixed parallel to said trimming electrode and a dielectric body sandwiched between the two electrodes. The trimming electrode is disposed in the air for enabling the trimming of the area of the trimming electrode, and the trimming electrode has a coarse adjustment portion parallel and aligned with said common electrode and a fine adjustment portion attached to the same plane of that of the coarse adjustment portion but outside of the common electrode. The oscillation frequency of the quartz-crystal piece is automatically picked up and the frequency is compared with the desired reference frequency, and according to the result of the comparison, the trimming electrode is trimmed so that the oscillating frequency becomes the desired reference frequency. The trimming is carried out first for the coarse trimming portion, and secondly for the fine adjustment portion.