Pioneer Corporation

Tohoku Pioneer Corporation

Sinsuke Konuma

Satoshi Hachiya

Koji Maekawa

Akihiko Furuto

A high performance speaker is provided and includes a simple structure magnetic circuit achieved without the need of a complicated manufacturing process, and a high performance speaker is provided and includes a simple structure diaphragm achieved without the need of a difficult process for forming a U shape of a narrow width in the diaphragm. A speakeris equipped with an inner-magnet-type magnetic circuitprovided with a magnet, a plateand a yoke, a voice coil, and a diaphragmsupporting the voice coilin place close to the end of the platewhile allowing the voice coil to vibrate. The yokeis formed in an approximately flat plate shape having a diameter equal to or larger than that of the plate. The diaphragmhas a dome-shaped vibrating sectionformed in a central portion, a cone-shaped vibrating sectionhaving an outer periphery supported by a speaker frame, and a voice coil bobbinwhich is formed between the dome-shaped vibrating sectionand the cone-shaped vibrating section. The voice coil bobbinis formed in an L-shaped cross section bending outward from an end of a tubular portion in which the voice coilis mounted. The dome-shaped and cone-shaped vibrating sections and the voice coil bobbin are molded together in one piece.

Speaker and magnetic circuit

A diaphragm and a speaker unit which can prevent generation of abnormal sound by suppressing rolling phenomenon. The speaker unit has a diaphragm. The diaphragm includes a portion for supporting a voice coil, and a sound emitting portion formed continuously to one end thereof. The voice coil supporting portion has a shape extending reversely to the sound emitting direction. The sound emitting portion includes a step portion having a surface substantially perpendicular to the sound emitting direction, and a bent portion having a cross-section bent toward the inside of the voice coil supporting portion from one end of the step portion. Consequently, the voice coil supporting portion is movable to describe an arc having a radius substantially equal to the radius of curvature at the bent portion of the voice coil supporting portion and a basic point substantially identical to the center of the bent portion in the bending direction as the voice coil moves in the sound emitting direction or in the reverse direction. Rolling phenomenon can thereby be retarded, the voice coil supporting portion can be prevented from colliding against a magnetic circuit when the speaker unit is driven and generation of abnormal sound can be prevented.

Growing community of inventors

Yamagata, Japan

Sinsuke Konuma