| 摘要 |
PURPOSE:To eliminate a spark discharge from an electrified human body to a terminal part, by separating an acoustic space at the front plane of a diaphragm from a magnetic circuit and a conductive part, or making long a distance between them. CONSTITUTION:A baffle plate 21 molded with a material having a high magnetic permeability has a guide 34 fitting in the outer peripheral guide 33 of the diaphragm in a frame 28, and it is adhered with a fitting part, and also, the separation of the acoustic space at the front plane of a diaphragm 22 from the conductive part, such as a shield board that is also used as a terminal 29, etc., can be realized by packing the guide part 34 of the frame 28 having a notch with an adhesives to draw out a voice coil lead 24. The shield and terminal 29 made of the material having the high magnetic permeability, such as an iron, etc., molded at the baffle plate 21 has a vertical part extending to a plate 27 with a center pole at the outer periphery of a diaphragm guide part 33 in the frame 28, and constitutes a magnetic circuit 32 which induces a leakage magnetic flux to the front plane of a magnetic cavity 31 to the plate 27 with the center pole. In this way, when electrified object is approached to a unit, a discharge path is a path along the outside wall of the unit, and a breakdown can be prevented from being occurred.
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