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. 25, 2008
Filed:
Jul. 12, 2005
Jun Matsuzaki, Shiojiri, JP;
Takashi Kawaguchi, Shiojiri, JP;
Reiko Nagahama, Shiojiri, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
The frequency of a drive signal supplied to a piezoelectric actuatoris swept within a specific range, the consumption current of the piezoelectric actuatoris determined, and when the consumption current is equal to or greater than a reference value, the frequency of the drive signal supplied to the piezoelectric actuatoris shifted proportionate to a specific frequency and returned to its initial value, and the frequency sweep is continued. The resonance frequency component can be removed when the frequency of the drive signal supplied to the piezoelectric element is swept. Consequently, the piezoelectric element can be driven outside of the resonance frequency range at which the consumption current is highest, allowing extreme increases in the consumption current to be prevented and system failures due to the flow of an excessive consumption current to be avoided.