Patent ID: 6960868

Claim:
A piezoelectric electro-acoustic transducer comprising: a substantially rectangular piezoelectric diaphragm that vibrates in a surface-flexural mode in the thickness direction of the diaphragm in response to application of an alternating signal between electrodes disposed thereon; a casing having a support unit disposed in an internal periphery thereof for supporting four corners of the piezoelectric diaphragm; a terminal fixed to the casing such that an internal connection portion of the terminal is exposed in the vicinity of the support unit; a first elastic adhesive for holding the piezoelectric diaphragm to the casing and arranged between an external periphery of the piezoelectric diaphragm and the internal connection portion; a conductive adhesive for electrically connecting an electrode of the piezoelectric diaphragm and the internal connection portion of the terminal and being arranged between the electrodes of the piezoelectric diaphragm and the internal connection portion of the terminal via the upper surface of the first elastic adhesive; and a second elastic adhesive for sealing between the external periphery of the piezoelectric diaphragm and the internal periphery of the casing; wherein a cradle is provided in the internal periphery of the casing and below the piezoelectric diaphragm in the vicinity of the first elastic adhesive to provide a gap for preventing a flow of the first elastic adhesive, the first elastic adhesive is located at a position lower than the support unit and between an upper surface of the cradle and a bottom surface of the piezoelectric diaphragm.