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. 07, 2014
Filed:
Jun. 06, 2012
Osamu Urano, Okaya, JP;
Osamu Urano, Okaya, JP;
Seiko Epson Corporation, , JP;
Abstract
A piezoelectric actuator includes a frequency controller that controls the frequency and power of the driving signal, wherein when the phase difference falls within a predetermined range, the control unit stores the value of the frequency of the driving signal as a first frequency memory value, sets a voltage to a upper limit voltage value, and performs control of adjusting the frequency of the driving signal so that the phase difference is maintained to be within a predetermined range, and when the frequency of the driving signal is changed from the first frequency memory value by an amount exceeding a first value determined in advance, the control unit stores the value of the frequency of the driving signal as a second frequency memory value and sets the voltage to a lower limit voltage value lower than the upper limit voltage value.