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. 11, 1978
Filed:
Oct. 05, 1976
Hubert Matthey, Brugg, CH;
Abstract
The inversion temperature of a quartz piezoelectric resonator is determined y exciting the resonator at its resonant frequency, bringing the resonator to a first temperature T.sub.h, obtaining the resonance frequency f.sub.o at the temperature T.sub.h as a standard of comparison for the subsequent measurement of resonator frequency variations, bringing the resonator to a second temperature T.sub.f and measuring the relative frequency spread (f-f.sub.o /f.sub.o) while the temperature is varying from T.sub.h to T.sub.f, detecting the maximum value of the frequency spread, and deducing the temperature at which the maximum value occurs. One of the first and second temperatures is greater and the other is less than the inversion temperature.