Patent ID: 8482185

Claim:
Ultrasonic actuator, preferably for use in an ultrasonic motor, in the form of a piezoelectric plate ( 1 ) with a length L, a height H and a thickness t, wherein the piezoelectric plate ( 1 ) has a lateral plane of symmetry Sq, a longitudinal plane of symmetry Sl and at least two main surfaces ( 2 ), and the piezoelectric plate ( 1 ) comprises at least two generators ( 7 , 8 ) arranged symmetrically with respect to the plane of symmetry Sq for generating ultrasonic standing waves, characterized in that the piezoelectric plate ( 1 ) has a shape that includes at least eight lateral faces, wherein at least two of the lateral faces are working surfaces ( 4 ) provided to contact elements to be driven, and at least two of the lateral faces are holding surfaces ( 5 ) provided to hold the piezoelectric plate ( 1 ), and the remaining lateral faces are free surfaces ( 6 ), wherein at least four free surfaces ( 6 ) are arranged at a same angle α with respect to the longitudinal plane of symmetry Sl and/or at a same angle φ with respect to the lateral plane of symmetry Sq.