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:
May. 12, 1998
Filed:
Mar. 13, 1995
Masahiko Takahashi, Tokyo, JP;
Primo Microphones, Inc., McKinney, TX (US);
Abstract
A piezoelectric speaker includes a casing and cover member having a transverse wall extending therebetween which forms a sound transmission channel having a spiral curved or double reverse bend shape and being of substantially continuously increasing cross sectional area between an inlet portion of said channel and an outlet opening to atmosphere. A driver element comprising a diaphragm formed of fiber reinforced epoxy, polyester or ABS resin has a piezoelectric ceramic disk secured thereto and supported in a recess formed on the cover member. A sound transmission opening in the cover member communicates with the inlet portion of the sound transmission channel. The diaphragm may be formed integral with the cover member. The speaker has the capability of expanding the frequency band width of audible sound at relatively high sound pressure levels.