| 摘要 |
PURPOSE:To obtain a highly efficient high capacity ultrasonic motor by forming a frictional driving member and a slip piezoelectric element circularly on the outer diameter part of a rotary drum. CONSTITUTION:Upon application of a high frequency pulse voltage E onto a tubular piezoelectric element 1 and a slip piezoelectric element 3, the tubular piezoelectric element 3 contracts radially to move the slip piezoelectric element 3 and a driving member 4 in the inner radial direction thus bringing the gap deltabetween a rotary drum 6 and the driving element 4 zero and producing a pressing force on the surface. At the same time, the slip piezoelectric element 3 displaces to the left at the tip in the thickness direction thus moving the integral driving member 4 leftward. Frictional force is produced between the driving member 4 and the rotary drum 6 and the frictional force transmits the leftwar motion of the slip piezoelectric element 3 thus rotating the rotary drum 6 leftward. Voltage goes to zero level at next instance, and respective piezoelectric elements 1, 3 recover with their resiliency. When the operation is repeated, the rotary drum 6 is unilaterally driven continuously. |
