Abstract: In a piezoelectric transformer having a piezoelectric body in polarized condition, input electrodes provided on the surface of the piezoelectric body and applied an alternating voltage of a frequency depending upon the resonance frequency of the piezoelectric body and a leading electrode provided on the surface of the piezoelectric body and taking out a voltage depending upon vibration of the piezoelectric body, and a grounding electrode is further provided on the surface of the piezoelectric body and electrically isolated from the input electrode and taking out output voltage in cooperation with the leading electrode by forming a pair, depending on the vibration of the piezoelectric body. Thus, even when an alternating voltage having a frequency equal to the resonance frequency of the piezoelectric body, respective junctions have sufficient strength against vibration.

Abstract: In a piezoelectric transformer comprising first and second driving blocks which are operable in a piezoelectric transverse vibration mode to induce a longitudinal vibration in a longitudinal direction and a voltage generating block formed between the first and the second driving blocks and which is operable in a piezoelectric longitudinal vibration mode in response to the longitudinal vibration, the voltage generating block comprises first and second voltage generating portions for generating an output voltage by the piezoelectric longitudinal vibration mode, a primary voltage producing portion formed between the first and the second voltage generating portions, and first and second secondary voltage producing portions formed at both sides of the voltage generating block. The first and the second driving blocks are supplied, in common, with an a.c. voltage through first and second input terminals.