| 摘要 |
PURPOSE:To reduce the necessary space by fixing one edge of a spiral piezoelectric element consisting of a flat plate-shaped piezoelectric element and the wedge-shaped electrodes and installing the other edge onto a movable body. CONSTITUTION:The movable supporting sleeve 8 of a spring 7 for pressing the needle valve 6 of a unit injector is connected with a spiral piezoelectric body 9. Said spiral piezoelectric body 9 consists of a disc-shaped piezoelectric element 9a and the wedge-shaped electrodes 9b and 9c, and a piezoelectric strain is generated by applying a prescribed voltage between the both lead wires 11a and 11b. One edge of the spiral piezoelectric body 9 is fixed, and the other edge is installed by the movable supporting sleeve 8. Therefore, a large piezoelectric strain force is generated, and space can be reduced. |
