Patent ID: 6807282
Filing Date: 2004-10-19
Classification: B06B,H04R

Abstract:
A structure within a cylindrical housing for mounting an electromagnetic induction actuator comprising,a magnetic circuit comprising a pole piece and a magnet connected as one piece, and a yoke that holds the pole piece and magnet together with a magnetic gap formed between the yoke and the pole piece, the magnetic circuit supported within the housing by leaf springs; a diaphragm, to the inward side of which is attached a voice coil, the voice coil projecting into the magnetic gap between the pole piece and the yoke, and the diaphragm extending inside the housing through a first open side; a terminal fitting that is attached to a terminal block that projects outward from the side wall of the housing and lead wires that electrically connect the voice coil and the terminal fitting; wherein the terminal block is facing a second open side of the housing in which the diaphragm is fitted and fixed, and a pad of elastic material is sandwiched between the second open side of the housing and the surface of a circuit board on the side of the housing where a leaf spring projects, so that pressing the terminal fitting against a conductive pattern of the circuit board forms an electrical connection to the circuit board; and a bushing of elastic material with circular extension flanges that covers the outside of the side wall of the housing, except for the terminal fittings on the terminal block, and that covers the first open side of the housing, such that the extension flange that covers the first open side of the housing becomes a pad that is sandwiched between the housing and the surface of the circuit board, and the extension flange that covers the second open side of the housing is positioned inside the outer casing as a seal that surrounds sound holes.