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:
Mar. 28, 2006
Filed:
Oct. 31, 2002
Satoshi Koura, Mie, JP;
Takashi Suzuki, Mie, JP;
Keiji Ishikawa, Mie, JP;
Kazuro Okuzawa, Mie, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A loudspeaker comprising at least one magnet, a yokefixed to a bottom surface of the magnet, a flat platefixed on an upper surface of the magnet, a magnetic circuithaving a magnetic gapformed between the plate and the yoke, and a flat diaphragmprovided with a coildisposed above the magnetic gap. The magnet has a width greater than that of the plate, and at least a part of the upper surface of the magnet is exposed so that it directly faces the diaphragm. According to the structure of the present invention, a larger volume magnet can be used without increasing the size of the magnetic circuit. Furthermore, as magnetic flux can be concentrated in an upper region of the magnetic gap, the magnetic circuit becomes efficient and compact. Thus a compact and high-efficiency loudspeaker for high frequency sound reproduction can be provided.