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. 09, 1993
Filed:
May. 04, 1992
Hisao Banno, Nagoya, JP;
Kohji Ogura, Nagoya, JP;
NGK Spark Plug Co., Ltd., Aichi, JP;
Abstract
A high unidirectivity piezoelectric element whose d.sub.31, d.sub.33 or d.sub.h is substantially zero. The element may be in the form of a sheet or a cable and includes a pair of electrodes, and a piezoelectric layer interposed between the pair of electrodes and containing two, first and second inorganic piezoelectric materials which have different coercive forces from each other and which are polarized in opposite directions. The element may be obtained by first applying a direct current voltage to a layer containing the first and second piezoelectric materials to polarize the both piezoelectric materials in one direction, and then applying a reverse direct current voltage thereto so that one of the piezoelectric materials having a smaller coercive force is selectively polarized in the other direction.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile