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:
Mar. 09, 2010
Filed:
Mar. 10, 2005
Takashi Kawaguchi, Shiojiri, JP;
Akihiro Sawada, Matsumoto, JP;
Yutaka Yamazaki, Suwa, JP;
Makoto Okeya, Shiojiri, JP;
Takashi Kawaguchi, Shiojiri, JP;
Akihiro Sawada, Matsumoto, JP;
Yutaka Yamazaki, Suwa, JP;
Makoto Okeya, Shiojiri, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
An electronic device comprising a power source, a piezoelectric actuator A, and a drive control apparatusfor controlling the driving of the piezoelectric actuator, wherein the drive control apparatusis provided with a drive circuitfor supplying a drive signal SDR to the piezoelectric element of the vibrating body, a phase difference detection meansfor detecting the phase difference indicating the vibration state of the vibrating body, a comparison voltage setting circuitfor correcting the target phase difference to be the target for the vibration state, and a drive frequency setting meansfor comparing the phase difference with the target phase difference; and the piezoelectric actuator A can be driven with high efficiency independent of the drive voltage by modifying the drive frequency of the drive signal SDR so that the phase difference approaches the target phase difference based on the results of the above comparison.