Patent ID: 6965680
Filing Date: 2005-11-15
Classification: H04R

Abstract:
1. A piezoelectric electro-acoustic transducer comprising: a piezoelectric vibration plate having a plurality of piezoelectric ceramic layers laminated to each other with an internal electrode interposed between the piezoelectric ceramic layers, and main surface electrodes provided on the front and back surfaces thereof whereby area bending vibration is produced by applying an AC signal between the main surface electrodes and the internal electrode; a resin film having a size that is greater than the size of the piezoelectric vibration plate, the piezoelectric vibration plate being bonded to a central portion of a surface of the resin film; and a case accommodating the piezoelectric vibration plate and the resin film; wherein the piezoelectric vibration plate has an area that is about 40% to about 70% of that of the resin film; an inner peripheral surface of the case is provided with a supporting portion having a frame shape that is larger than that of the piezoelectric vibration plate; and an outer peripheral portion of the resin film having no piezoelectric vibration plate bonded thereto is supported by the supporting portion of the case.