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. 26, 2009
Filed:
Jul. 18, 2005
Tetsuya Onuma, Tendo, JP;
Shinichi Sato, Saitama, JP;
Tomoaki Shoji, Saitama, JP;
Toshirou Araki, Saitama, JP;
Tetsuya Onuma, Tendo, JP;
Shinichi Sato, Saitama, JP;
Tomoaki Shoji, Saitama, JP;
Toshirou Araki, Saitama, JP;
Pioneer Corporation, Tokyo, JP;
Tohoku Pioneer Corporation, Yamagata, JP;
Abstract
A speaker apparatus is configured such that a speaker unit including a single magnetic circuit system, a plurality of vibration systems and a case is housed inside a speaker box. In the speaker unit, magnetic gaps having a magnetic field of the same magnitude are defined by a magnet holder, a magnet and a yoke in each of the vibration systems. In one vibration system and the other vibration system, voice coils are wound around voice coil bobbins in directions reverse to each other. Consequently, the vibration systems are moved in directions opposite to each other by the same force by applying the same electric signal to the voice coil in each of the vibration systems from an amplifier. Therefore, acoustic waves are radiated in the directions opposite to each other.