Ultrasonic motor of travelling wave type - has piezoelectric transducer of cylindrical platelets, adhered to stator surface

摘要

The travelling wave type ultrasonic motor has a metal stator energised by a piezoelectric transducer, and a rotor moved along by friction, assisted by intermediate material. The piezoelectric transducer consists of cylindrical platelets (4) adhered to the stator surface. The platelets are polarised orthogonally w.r.t. the stator (1) surface. Pref. the platelets are polarised in a mode, corresp. to their thickness arrangement. They may be alternately polarised in opposite sense and may be arranged in an angular spacing of a half-wavelength. ADVANTAGE - Reduced mfg. and assembly expenditure, and improved efficiency.