Patent ID: 8634587

Claim:
An acoustic conversion device comprising: (a) a driving unit including (1) a pair of magnets disposed so as to face one another, (2) a yoke to which said pair of magnets are attached, (3) a coil to which driving current is supplied, (4) an armature with a vibrating portion which vibrates when driving current is supplied to said coil, said armature disposed between said pair of magnets with said vibrating portion extending through said coil; and (b) a diaphragm unit including (1) a holding frame having an opening, (2) a resin film adhered to said holding frame, said resin film covering said opening of said holding frame, (3) a diaphragm held on an inner side of said holding frame and adhered to said resin film, and (4) a beam portion integral with the diaphragm, said beam portion (i) comprising a portion of the diaphragm that is bent such that the beam portion extends in a different direction than does the diaphragm, and (ii) propagating the vibration of said vibrating portion to said diaphragm; wherein, an edge portion of the beam portion is attached to an edge portion of said vibrating portion of said armature, a predetermined gap is present between an edge of said diaphragm, and an inner face of said holding frame, the resin film is secured to the diaphragm and the holding frame while covering the predetermined gap, and a reinforcing member in said predetermined gap contacts each of said resin film, said diaphragm, and said holding frame, and adheres all of them together, said reinforcing member in the predetermined gap being effective to reinforce the resin film that covers the predetermined gap.