Patent ID: 7692363

Claim:
For an acoustic transducer comprising: a pair of electro-mechanical bender pieces; a substrate to which the pair of bender pieces are fixedly attached to opposed planar side surfaces of the substrate; an enclosing housing that defines an interior closed space of predetermined size; said substrate having opposed ends that are respectively attached to opposed locations of the enclosing housing so as to divide the interior space into separate space portions; means for electrically exciting the pair of bender pieces; the improvement comprising: a pair of respective and separately disposed masses attached to the center of the substrate at respective opposed planar side surfaces of the substrate; said pair of respective and separately disposed masses disposed one in one of the space portions and the other in the other space portion; each said mass including a main mass portion and a contiguous mass connection portion that is smaller in mass than the main mass portion; each said bender piece having a respective center through passage for receiving therethrough a respective mass connection portion of said mass for attachment of the respective mass connection portions to opposed side surfaces of the substrate; said mass connection portions each having respective free ends that are attached to the opposed surfaces of the substrate to provide a direct metal-to-metal contact of the mass connection portions with the respective opposed planar side surfaces of the substrate; said pair of respective and separately disposed masses providing enhanced housing motion and attendant acoustical intensity under electrical drive conditions.