| 摘要 |
PROBLEM TO BE SOLVED: To provide a laminate type piezoelectric actuator capable of realizing a long life by preventing stress damage, and a manufacturing method thereof.SOLUTION: In a laminate type piezoelectric actuator 100, piezoelectric ceramic layers 110 and internal electrodes 120 are alternately laminated. A density of piezoelectric ceramic near an outer periphery of the internal electrode 120 is smaller than a density of piezoelectric ceramic near a center part of the internal electrode 120. A displacement amount of the piezoelectric ceramic near the outer periphery of the internal electrode 120 is smaller than a displacement amount of the piezoelectric ceramic near the center part of the internal electrode 120. Thereby, a density or a piezoelectric characteristic of an inactive part 140 can be reduced relative to an active part 130. Then, the displacement amount at that portion can be reduced during an operation, so as to reduce a stress generated near its boundary portion. Also, because it is difficult that cracks proceed at a low density portion, and therefore, stress breakage of the laminate type piezoelectric actuator 100 can be prevented to realize a long life. |
