Nisca Corporation

Nippon Seimitsu Kogyo Kabushiki Kaisha

Tamotsu Iijima

Kazuhide Sano

An ultrasonic actuator comprising an elastic vibration member of a rectangular plate is excited by vibrators attached to at broadest excitation surfaces, thereby concurrently inducing longitudinal and bending vibrations. Extraction of vibrational motion from the vibration member being excited to vibrate can be carried out by pressing a moving object against one of the most slender planes perpendicular to the excitation surfaces. Since the length in the direction in which the moving object is pressed against the vibration member is sufficiently larger, the vibrational characteristics of the vibration member can be prevented from being changed, and therefore, the moving object can be driven with high efficiency.

Ultrasonic actuator

An ultrasonic actuator using longitudinal and bending vibrations which are effectively coupled by controlling piezoelectricity generated in one of piezoelectric members attached onto an elastic vibrational member. Discharging electric charge induced in the piezoelectric member due to vibrations excited in the vibrational member, the piezoelectric member varies in stiffness to bring about electrical asymmetry within the vibrational member and allow the vibrations induced in the vibrational member to be coupled. Consequently, the ultrasonic actuator can be activated by single-phase alternating current with high efficiency.

Vibration-coupling type ultrasonic actuator and method for operating the

Standing wave vibrations which are generated in an elastic vibration member by a vibrator can be effectively converted into a linear or rotary motion by transmitting the standing wave vibrations to a moving member through motion extracting means which are arranged on the vibration member at intervals of half wavelength of the standing wave and each located on a portion substantially exclusive of the node and loop of the standing wave. According to this method, a linear or rotary motor of high performance can be accomplished.

Growing community of inventors

Kofu, Japan

Tamotsu Iijima