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:
Jan. 06, 2009
Filed:
Jun. 07, 2007
Yasuhiro Fukagawa, Obu, JP;
Tsutomu Nakamura, Kariya, JP;
Takamichi Kamiya, Kasugai, JP;
Noboru Nagase, Anjo, JP;
Hideo Naruse, Chiryu, JP;
Yasuhiro Fukagawa, Obu, JP;
Tsutomu Nakamura, Kariya, JP;
Takamichi Kamiya, Kasugai, JP;
Noboru Nagase, Anjo, JP;
Hideo Naruse, Chiryu, JP;
Denso Corporation, , JP;
Nippon Soken, Inc., , JP;
Abstract
In a driving device for a piezoelectric actuator, when a driving signal is input, a charging switch is repetitively turned on/off to charge and expand the piezoelectric actuator under the state that a discharging switch is turned off. Thereafter, when the input of the driving signal is stopped, the discharging switch is repetitively turned on/off under the state that the charging switch is turned off, thereby discharging and contracting the piezoelectric actuator. Particularly, during the charging period, the charging switch is turned on at a fixed period, and the charging switch is turned off when an integration value of current flowing in a charging circuit at the ON-time of the charging switch reaches a target charge amount.