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. 02, 1994
Filed:
Aug. 23, 1993
Hirofumi Kawashima, Sendai, JP;
Abstract
A torsional quartz crystal resonator has a specific cut type resulting in improved frequency temperature behavior. The cut type is defined by rotating a Z plate quartz crystal around an x-axis at an angle .phi. in the range of 0.degree. through 30.degree. and by further rotating the plate around a z'-axis at another angle .theta. in the range of -20.degree. through -10.degree. or +10.degree. through +20.degree.. The resonator has a thickness z.sub.0 and a width x.sub.0 determined such that a thickness-to-width ratio Rzx=z.sub.0 /x.sub.0 is set within the range of 0.6 through 1.1 to make the first order temperature coefficient substantially zero in combination with the optimum angles .phi. and .theta.. Excitation electrodes are disposed on major faces of the resonator normal to the z' axis, and a connecting electrode is disposed on a side face of the resonator to reduce the series resistance R.sub.1.