THICKNESS LONGITUDINAL VIBRATION PIEZOELECTRIC TRANSFORMER AND ITS DRIVE METHOD

摘要

PURPOSE:To provide a small-sized piezoelectric ceramic transformer for power supply service which is free of electrode detachment or porcelain breakdown during polarization processing and hence provides a high mechanical quality factor Qm and high power transmission efficiency. CONSTITUTION:As illustrated in Fig. 1, a piezoelectric ceramic transformer comprises a low impedance section 11 which laminates piezoelectric ceramics multilayers 111 to 115 whose thickness is diversified and a high impedance section 12 and aninternal electrode 16. Polarization processing is carried out for the low impedance section 11 and the high impedance section in the same thickness direction and the same direction. In the low impedance section, one and more piezoelectric ceramic layers are arranged to differ from other layers in their thickness.