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:
Dec. 20, 2005
Filed:
Nov. 27, 2002
Takashi Ogura, Toyonaka, JP;
Kousaku Murata, Kawanishi, JP;
Takashi Ogura, Toyonaka, JP;
Kousaku Murata, Kawanishi, JP;
Matsushita Electric Industrial Co., Ltd., Osaka-fu, JP;
Abstract
A piezoelectric speaker improved in acoustic features by weight reduction of a diaphragm of the piezoelectric speaker without decreasing stiffness of the diaphragm or a coefficient of thermal expansion of surfaces of the piezoelectric speaker is provided. The diaphragm having placed thereon a piezoelectric element is made of a sandwich-laminate clad material using different materials. For example, surface materials made of 42 alloy each having a thickness of 10 μm and a core material made of aluminium having a thickness of 30 μm form a clad material having a thickness of 50 μm. The formed clad material is processed into an arbitrary shape to form the diaphragm of the piezoelectric speaker. With this diaphragm, it is possible to keep the stiffness and the coefficient of thermal expansion of the 42-alloy diaphragm having the thickness of 50 μm, and also achieve weight reduction by approximately 40%.