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. 05, 1993
Filed:
Jun. 24, 1991
Tetsuo Shirasu, Tokyo, JP;
NEC Corporation, , JP;
Abstract
A piezoelectric effect device has a piezoelectric body comprised of a sintered multilayer pillar composed of alternately laminated piezoelectric ceramic sheets and internal electrodes such that edges of the internal electrodes are alternately insulated every one another layers along opposite side faces of the sintered multilayer pillar, and a pair of external electrodes provided on the opposite side faces to electrically connect to noninsulated edges of the internal electrodes. There is provided a metal stem having a pair of hermetically sealed external terminals electrically coupled to the pair of external electrodes. A metal case having flexibility in a displacement direction of the piezoelectric body is seal-welded to the metal stem at their contacts to hermetically enclose the piezoelectric body. A pair of metal pads having a linear thermal expansion coefficient less than ten times as that of the piezoelectric body are provided to substantially cover opposite end faces of the piezoelectric body. One metal pad is centrally spot-welded to an inner face of the metal stem in opposed relation to one end face of the piezoelectric body and is secured thereto by an adhesive, and the other metal pad is centrally spot-welded to an inner face of the metal case in opposed relation to the other end face of the piezoelectric body and is secured thereto by an adhesive.