Electrical acoustic converter

摘要

Disposed within a space formed between a base cover ( 2 ) and a top cover ( 1 ) attached to the base cover ( 2 ) is an electromagnetic sound generating part which has a diaphragm ( 9 ) attached to the base cover ( 2 ) and a drive part causing the diaphragm ( 9 ) to vibrate. The drive part includes a yoke ( 5 ) fitted in the base cover ( 2 ), a magnet ( 7 ) mounted on the yoke ( 5 ), a top plate ( 8 ) mounted on the magnet ( 7 ) and an exciting coil ( 6 ) disposed to oppose to side surfaces of the magnet ( 7 ) and top plate ( 8 ). Coil contact springs ( 10 ) are contained into housings ( 2 a) provided on portions of the base cover inside than an outer peripheral edge of the diaphragm. The coil contact springs ( 10 ) act to connect the exciting coil ( 6 ) with an outside power source. The base cover ( 2 ) is provided with a pair of connecting pieces ( 11 ) or lead frames which are used to connect the exciting coil ( 6 ) and coil contact springs ( 10 ). The connecting pieces ( 11 ) are embedded in the base cover ( 2 ).