| 摘要 |
PURPOSE:To obtain an ultrasonic motor having stabilized characteristics in which frictional heat can be dissipated from the sliding part by disposing a heat dissipating member in the gap between the casing and the end face of an annular piezoelectric element applied on one end face of a resilient disc with no gap. CONSTITUTION:A piezoelectric element 2 is bonded tightly to one end face of the resilient disc 1 in an ultrasonic motor cylindrical metal bellows 10 having closed opposite ends respectively, with the piezoelectric element and the casing 7 is disposed between the piezoelectric element 2 and the casing 7. Liquid 11 having high heat transfer coefficient is encapsulated in the metal bellows 10 through an appropriate space so that the spring coefficient of the metal bellows 10, which is sufficiently lower than the rigidity of the resilient disc 1, is not increased by the encapsulated liquid 11. According to the constitution, frictional heat produced through sliding of the resilient disc 1 and a rotor 4 is transferred through the metal bellows 10 containing the liquid 11 thence dissipated to the casing 7. |
