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:
Jun. 07, 2011
Filed:
Mar. 27, 2008
Takamitsu Higuchi, Matsumoto, JP;
Yasuhiro Ono, Suwa, JP;
Takamitsu Higuchi, Matsumoto, JP;
Yasuhiro Ono, Suwa, JP;
Seiko Epson Corporation, , JP;
Abstract
An acceleration sensor includes: a piezoelectric vibration device; an oscillation circuit; and a detection circuit, wherein the piezoelectric vibration device includes a substrate, an insulation layer formed above the substrate, a vibration section forming layer formed above the insulation layer, a vibration section formed in a cantilever shape in a first opening section that penetrates the vibration section forming layer, a second opening section that penetrates the insulation layer and formed below the first opening section and the vibration section, and a piezoelectric element section formed on the vibration section, the oscillation circuit vibrates the piezoelectric vibration device at a resonance frequency, and the detection circuit detects a change in the frequency of vibration of the piezoelectric vibration device which is caused by an acceleration applied in a direction in which the vibration section extends, and outputs a signal corresponding to the acceleration based on the change in the frequency.