SLIM SPEAKER

摘要

PURPOSE: A compact speaker unit is provided to reduce the size of a speaker by attaching a center magnet in a ring-type outer magnet to make a magnetic circuit thin. CONSTITUTION: An outer magnet(90) is fixed in a lower plate(80). The outer magnet(90) has the shape of a ring with a hollow(91). A center magnet(100) is fixed in the hollow(91) of the outer magnet(90) at a certain distance from the hollow(91). Magnetic directions of the outer magnet(90) and the center magnet(100) are composed of N, S and N. The lower plate(80) has gripping parts(81) for the outer magnet(90) and the center magnet(100). A rim-shaped upper plate(50) is positioned on the outer magnet(90). A pull piece(100) is positioned in the hollow(51) of the upper plate(50) and fixed ton the center magnet(100). The upper plate(50) and the pull piece(11) are positioned on the same plane, and have a gap between them. A bobbin(60) has the lower end inserted into the gap.