| 摘要 |
PURPOSE:To prevent generation of an unnecessary vibration and to prevent the characteristic deterioration of an ultrasonic motor by uniformly dispersively disposing two sets of driving electrodes on piezoelectric elements, and applying two phase voltage to a common electrode corresponding to the two sets of driving electrodes. CONSTITUTION:In an electrode disposing structure to a piezoelectric element of a ring type ultrasonic motor, a piezoelectric base 1, a first driving electrode 2, and a second driving electrode 3 are provided. In the piezoelectric electrode disposing structure of a rear face, a first common electrode 4 corresponding to the first driving electrode 2 and a second common electrode 5 corresponding to the second driving electrode 3 are provided. Here, in order to generate two sets of standing waves, two phase voltage is applied to a first set made of the first driving electrode 2 and the first common electrode 4, and a second set made of the second driving electrode 3 and the second common electrode 5. Thus, a traveling wave can be excited only by one piezoelectric element. |
