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:
Jul. 17, 1984
Filed:
Dec. 06, 1982
Jan W Waanders, Eindhoven, NL;
Herman F van Heek, Eindhoven, NL;
Roger A Colson, Eindhoven, NL;
David J Perduijn, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A piezoelectric device, comprising a number of polarizable ceramic plates 1 which are stacked with intermediate metal plates which serve as electrodes. The stack is subjected to a large amount of preload by a preloading element having a relatively flat spring-force characteristic over the piezoelectric operating range of the device which is formed by a cylindrical housing having two sets of parallel pairs of slots 7, 10, rotationally displaced by 90 degrees, the preloading force being applied to the stack by threaded end plugs 4 and 5. The ceramic plates are polarized only after assembly and preloading.