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. 06, 1994
Filed:
Oct. 19, 1993
Applicant:
Inventors:
Takashi Kikuchi, Tokyo, JP;
Takashi Wada, Tokyo, JP;
Assignee:
TDK Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ; H04R / ;
U.S. Cl.
CPC ...
310324 ; 310322 ; 310348 ;
Abstract
The case has an opening and a wall section with a hole provided on the wall section and the wall section forms an inner space. The case also has a recessed area surrounding the hole. The piezoelectric diaphragm is supported around its periphery on top of the case so that an enclosure, including the hole, is formed within the inner space. An acoustic resistance sheet is bonded on to the wall section with the adhesive that is filled into the recessed area to close off the hole. With this structure, defective damping caused by seeping of the adhesive is prevented.