| 摘要 |
PURPOSE:To manufacture a high-reliability piezoelectric displacement element which caused no decrease in amount of displacement and shows less deterioration in insulation resistance even if driven under a high humidity environment by a method wherein the active part of the piezoelectric displacement element is coated with a glass having cracks filled with a resin. CONSTITUTION:A lead wire is soldered onto an outer electrode of an element baked with a glass in the difference in thermal expansion coefficient of about 30% and after covering the displacement surface with a masking tape, immersed in a liquid urethane resin to be pressure-reduced in a vacuum descicator for filling cracks with an urethane resin. Next, the whole body is heated to set the urethane and then coated with powdery resin by fluidifying immersion process and after releasing the masking tape, the epoxy resin is heated to be set. Through these procedures, when the piezoelectric displacement element is driven under high humidity, the reliability is to be enhanced due to less deterioration in the insulating resistance of the element, thereby enabling the applicable range of the piezoelectric displacement element to be increased. |
