STATOR AND VIBRATION PLATE OF ULTRASONIC MOTOR, AND ULTRASONIC MOTOR

摘要

PROBLEM TO BE SOLVED: To make it possible to obtain required speed characteristics without requiring a complicated control of AC voltage by sloping at least one of two side surfaces in a direction of a traveling a moving body of a stator contact portion. ;SOLUTION: Both the side surfaces 4a in the peripheral direction of each projection 4 are sloped to one direction (counter-clockwise) and thus a vibration component of the vibration of a traveling wave in one direction at the side where the each projection 4 is sloped becomes larger. Thus, a rotor 5 rotates at the sloped side of the projection 4, that is, when it rotates counter-clockwise, the ultrasonic motor will have a high speed rotation. On the contrary, if the rotor 5 rotates in a direction opposite to the sloped side, that is in the clockwise, its vibration component becomes smaller compared to the rotation in one direction, and the ultrasonic motor will have a low speed rotation. Thus, even though the frequency variable control is not performed, the rotor 5 of the ultrasonic motor can be rotated at a high speed in one direction and rotated at a low speed in the reverse direction only by controlling the phase of a high frequency AC voltage without performing a frequency variable control.;COPYRIGHT: (C)1999,JPO