Patent ID: 6211604
Filing Date: 2001-04-03
Classification: H02N

Abstract:
A method for assembling an ultrasonic motor, the method comprising:providing a stator having a piezoelectric element;arranging a rotor to face the stator, wherein the piezoelectric element vibrates the stator to rotate the rotor;locating a lining member between the stator and the rotor, wherein the lining member has a predetermined thickness in the axial direction of the motor;installing an elastic member for pressing the rotor toward the stator, wherein normal wear of the lining member changes the deformation of the elastic member in the axial direction of the motor, and wherein the force of the elastic member pressing the rotor changes in accordance with the axial deformation of the elastic member; andpre-loading the elastic member, during assembly such that its deformation in the axial direction of the motor is in a predetermined deformation range, wherein the variation of the pressing force is relatively small for any deformation amount within the predetermined deformation range; andchoosing the pre-loading of the elastic member such that the axial deformation of the elastic member due to complete wear of the lining member remains within the predetermined deformation range.