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:
Nov. 04, 2014
Filed:
Oct. 12, 2011
Mikio Arai, Aikoh-gun, JP;
Mikio Arai, Aikoh-gun, JP;
NHK Spring Co., Ltd., Kanagawa, JP;
Abstract
A method of testing a fitted state of a pair of piezoelectric elements fitted to form an actuator between a base member and a movable member, the piezoelectric elements in the actuator being arranged side by side in opposite polarity and being electrically connected in parallel with each other, and when a voltage is applied to the piezoelectric elements, minutely moving the movable member relative to the base member in a direction in which the piezoelectric members are arranged side by side. The method detects changes in capacitance of the piezoelectric elements with respect to changes in bias voltage applied to the piezoelectric elements, the bias voltage being changed within a predetermined range, and determines a fitted state of the piezoelectric elements according to a characteristic of the detected capacitance changes. The method correctly and easily determines whether or not the piezoelectric elements are correctly fitted to the actuator.