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. 15, 2009
Filed:
Nov. 22, 2004
Tomoyasu Takase, Mie, JP;
Mitsutaka Enomoto, Mie, JP;
Kazuya Yamasaki, Osaka, JP;
Kazutaka Kubo, Mie, JP;
Takeshi Shimokawatoko, Mie, JP;
Masahide Sumiyama, Mie, JP;
Tomoyasu Takase, Mie, JP;
Mitsutaka Enomoto, Mie, JP;
Kazuya Yamasaki, Osaka, JP;
Kazutaka Kubo, Mie, JP;
Takeshi Shimokawatoko, Mie, JP;
Masahide Sumiyama, Mie, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A loudspeaker includes a magnetic circuit having a magnetic gap, a frame coupled to the magnetic circuit, a voice coil having a first end positioned in the magnetic gap and a second end opposite to the first end, and a diaphragm coupled to the second end of the voice coil and the frame. The voice coil has a center axis provided through the first end and the second end. The diaphragm has a first portion in which the center axis of the voice coil is provided. The first portion of the diaphragm is provided inside the voice coil. The diaphragm further has a second portion outside the voice coil. One of the first portion and the second portion of the diaphragm has a cross section in a plane including the center axis, and the cross section of the one of the first portion and the second portion of the diaphragm has an elliptic-arc shape. This loudspeaker has a small thickness, has a high sound pressure level in a high frequency range, and secures a wide reproduction range in high frequencies.