Patent ID: 6847139

Claim:
A multifunctional vibration actuator comprising an approximately cylindrical housing having openings on both sides, a magnetic circuit part in which a pole piece and a yoke are integrally fixed and formed on a magnet so as to form a gap that affects as a magnetic gap, a diaphragm having a voice coil being attached on a surface, a suspension having a supporting portion that fixedly supports said magnetic circuit part, a cover to cover one of the openings, said diaphragm arranging said voice coil in the magnetic gap and being adhered on an edge of said housing so as to cover an opening on the opposite side of the opening being covered by said cover, a plurality of arms being elongated from an outer shape of the supporting portion along the outer shape, ends of the elongated arms being fixed on an inner side surface of said housing, and said magnetic circuit part vibrating in said housing by deflection of the arms upon application of an electrical signal to said voice coil, wherein at least one component of said housing, said diaphragm, and said cover is provided with a through hole, and an outer shape surface of said yoke is placed in proximity of the inner side surface of said housing to form a clearance, wherein said clearance is adjusted so that a frequency bandwidth, in which a vibration of said magnetic circuit part is obtained, can be enhanced by limiting the movement of air in a space formed by said diaphragm and said magnetic circuit part and in a space formed by said magnetic circuit part and said cover.