| 摘要 |
PURPOSE:To obtain a motor with high efficiency by setting a longitudinal oscillation half-wavelength resonance frequency of a single stator higher than a torsion oscillation half-wavelength resonance frequency of the stator simplex. CONSTITUTION:A torsion oscillation excitation piezo-electric ceramics 1 and a longitudinal oscillation excitation piezo-electric ceramics 2 are held between cylindrical metallic members 3 and 4, and are tightened as a unit by using a bolt 5 to form a stator. In that case, a longitudinal oscillation half-wavelength resonance frequency of the stator is about 1.6 times of a torsion oscillation half-wavelength resonance frequency. Metallic rotors 6 are pressure welded to the ends of the stator by using a bearing 7, a resin-like elastic substance 8, a nut 9 and a bolt 10 to form an ultrasonic motor, and clamping pressure of the rotor and stator is adjusted to accord the torsion oscillation half- wavelength resonance frequency determined by about stator simplex with the longitudinal oscillation resonance frequency determined by the constitution of the whole motor (which is greatly lower than the frequency determined by the stator only). |
