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:
Apr. 14, 2009
Filed:
May. 27, 2004
Applicants:
Mitsutaka Enomoto, Matsusaka, JP;
Hiroshi Yano, Tsu, JP;
Takeshi Shimokawatoko, Hisai, JP;
Inventors:
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04R 25/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A loudspeaker used mainly for mobile communication equipment such as a mobile telephone and having two loudspeaker parts provided in one frame is provided. In the loudspeaker, a yoke has a groove portion and a second voice coil disposed in this groove portion drives a second diaphragm. Since the groove portion functioning as a magnetic gap is formed by processing the yoke, variation in the magnetic gap, which conventionally occurred at the time of incorporation, is eliminated and accuracy is improved, thus stabilizing the sound pressure frequency property.