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:
Oct. 02, 2012
Filed:
Apr. 14, 2010
Tomoya Yorita, Sayama, JP;
Junichiro Yamakawa, Sayama, JP;
Shigenori Watanabe, Sayama, JP;
Mitsuaki Koyama, Sayama, JP;
Tomoya Yorita, Sayama, JP;
Junichiro Yamakawa, Sayama, JP;
Shigenori Watanabe, Sayama, JP;
Mitsuaki Koyama, Sayama, JP;
Nihon Dempa Kogyo Co., Ltd., Tokyo, JP;
Abstract
To shorten the time required for an oscillation frequency to stabilize in a sensing device sensing a substance to be sensed by using the fact that a natural frequency of a piezoelectric resonator changes when the substance to be sensed is adsorbed by an adsorption layer formed on the piezoelectric resonator. A sensing device includes: an oscillator circuitoscillating a quartz-crystal resonator; and an intense excitation circuit that is formed by the oscillator circuitincluding a series circuit of a resistorand a third transistorof PNP type and that intensely excites the quartz-crystal resonatorconnected to the oscillator circuitfor a period of time preset by a one-shot circuitby supplying the quartz-crystal resonatorwith high power equal to or more than twice regular power supplied at the time of the measurement of the substance to be sensed, to stabilize the oscillation of the quartz-crystal resonator. When the connection of the quartz-crystal resonatoris detected, the one-shot circuitbrings the oscillator circuitinto an aging state and the high power is supplied to the quartz-crystal resonatorto intensely excite the quartz-crystal resonator, thereby eliminating the distortion and stress of a quartz-crystal plate