| 摘要 |
PURPOSE:To effectively drive an ultrasonic motor by reducing a starting current, decreasing starting current and suppressing heat generated from a driving circuit. CONSTITUTION:An inductance element 32 is connected in series with a plurality of electrodes disposed on the surface of a piezoelectric element for vibrating a vibration by generating mechanical vibration when alternating voltage is applied. The mechanical resonance frequency of a mechanical vibrating part is so set that X of an admittance Y=jx of a circuit in which an RLC series circuit of the part having an equivalent resistance of a resistance value Rm, an equivalent coil of a self-inductance Lm and an equivalent capacitor of an electrostatic capacity Cm is excluded from the equivalent circuit of an ultrasonic motor becomes a negative value. |
