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:
Jun. 12, 2007
Filed:
Dec. 23, 2003
Sawako Usuki, Kobe, JP;
Shuji Saiki, Uda-gun, JP;
Sawako Usuki, Kobe, JP;
Shuji Saiki, Uda-gun, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
In an electroacoustic transducer of the present invention, a casing supports a diaphragm, a drive coil is provided on the diaphragm, a first magnetic structure has a first space in a center thereof provided within the casing such that a center axis penetrates the first space, and a second magnetic structure has a second space in a center thereof provided within the casing on a side opposed to the first magnetic structure with respect to the diaphragm, such that the center axis penetrates the second space. The first magnetic structure is oriented such that a magnetization direction thereof is parallel to the center axis. The second magnetic structure is oriented such that a magnetization direction thereof is opposite to the magnetization direction of the first magnetic structure.