Panasonic Intellectual Property Management Co., Ltd.

Panasonic Corporation

Panasonic Automotive Systems Co., Ltd.

Shinya Kagawa

Mitsukazu Kuze

Hiroyuki Takewa

Koji Sano

Kenichi Ajiki

Goro Tsuchiya

Kiyohisa Hattori

Akihiro Yogo

Satoshi Itoh

An electroacoustic conversion device includes a vibration plate, an inner voice coil attached to the vibration plate, an outer voice coil attached to the vibration plate outside the inner voice coil to surround the inner voice coil, a magnet, a yoke, and the frame which holds the vibration plate and the yoke. The magnet includes a wiring portion which is in a form of a through hole or a notch in which inner signal lines for the inner voice coil are provided.

Electroacoustic conversion device

A speaker device that includes: two magnetic circuits arranged side by side and each including a magnetic gap; two voice coil bodies each corresponding to a shape of the magnetic gap and arranged in the magnetic gap in an inserted state; a diaphragm to which the two voice coil bodies are coupled, the diaphragm having a width shorter than a length in a direction in which the two magnetic circuits are arranged; and a frame to which the diaphragm and the two magnetic circuits are attached. In the speaker device, the two voice coil bodies include two coils connected in series, the two coils being connected to a pair of input terminals for receiving an input of an electric signal, the pair of input terminals being disposed between the two voice coil bodies.

Speaker device

An electroacoustic transducer includes a diaphragm, a frame disposed to surround a rim portion of the diaphragm, a front support body and a rear support body that couple the diaphragm and the frame, and a magnetic circuit provided with an annular magnetic gap facing a rear face of the diaphragm. The electroacoustic transducer further includes a voice coil body having a rear end disposed in the magnetic gap and a front end coupled to the diaphragm.

Electroacoustic transducer

A loudspeaker includes a diaphragm, a magnetic circuit, and a frame. The frame includes an outer peripheral part supporting the diaphragm, a center part supporting the magnetic circuit, and a connection part connecting the center part to the outer peripheral part. The outer peripheral part molded with resin includes an inner wall, an outer wall facing the inner wall, and a reinforcing rib provided between the inner wall and the outer wall.

Loudspeaker, and electronic apparatus and mobile device using the loudspeaker

A speaker () includes a cylindrical diaphragm () which has closed ends, an edge () which supports the diaphragm () in a manner which allows the diaphragm to vibrate, a voice coil bobbin () around which a voice coil () is wound and which is connected to the diaphragm (), and a magnetic circuit for driving the voice coil ().

Growing community of inventors

Osaka, Japan

Shinya Kagawa