Nemoto Kyorindo Co., Ltd.

Shinsei Corporation

Mitsubishi Jukogyo Kabushiki Kaisha

Toshiiku Sashida

Toshio Kanetaka

Makoto Udagawa

Takashi Akaba

Isao Shirasu

Tadashi Nagashima

Kyoichi Yoshioka

Yoshimasa Tsukamoto

Provided is an injector in which adhesion between a stator and a rotor of an ultrasonic motor can be released efficiently. An injector () which injects a chemical liquid includes: an ultrasonic motor unit () including an ultrasonic motor (); a drive mechanism () to be driven by the ultrasonic motor unit () so as to feed the chemical liquid when the ultrasonic motor () rotates forwardly; and a control device () which controls the ultrasonic motor () of the ultrasonic motor unit (). The ultrasonic motor () includes a stator () and a rotor (), and the control device () controls the ultrasonic motor () to alternately repeat forward rotation and reverse rotation so that adhesion between the stator () and the rotor () is released.

Injector and control method for an ultrasonic motor

An electrostatic motor has a container having a main body, a stator fixed to the main body in the container; and a rotor which is disposed opposite to the stator in the container, and which is pivotally supported so as to freely rotate via a rotating shaft. The stator has first electrodes attached to a first electrode support and second electrodes attached to a second electrode support. The first electrodes and the second electrodes are electrically insulated. The rotor has third electrodes attached to a third electrode support and fourth electrodes attached to a fourth electrode support. The third electrodes and the fourth electrodes are electrically insulated, and the third electrodes and the fourth electrodes are respectively arranged at different positions from the first electrodes and the second electrodes in a radial direction of the rotor so as to be spaced apart from the first electrodes and the second electrodes.

Electrostatic motor

An electrostatic motor has a disc-shaped stator and a disc-shaped rotor are opposed to each other in a vacuum container. In the stator, first electrodes and second electrodes, which are attached to electrode supports, and which are electrically insulated from each other by an insulator, are arranged alternately in the circumferential direction. In the rotor, first electrodes and second electrodes, which are attached to electrode supports, and which are electrically insulated from each other by an insulator, are arranged alternately in the circumferential direction. The first electrodes and the second electrodes on the side of the stator are arranged at a spacing of two or more rows at a predetermined distance from the center of a rotating shaft. The first electrodes and the second electrodes on the side of the rotor are arranged at a predetermined distance from the center of the rotating shaft and at an intermediate position between the rows of the first electrodes and the second electrodes on the side of the stator. As a result, the electrostatic motor can establish a high electric field in the vacuum so that it can rotationally drive with a sufficient driving force.

A small-sized ultrasonic motor can produce a high torque and a stable turning force. The ultrasonic motor has: a cylindrical casing, a hollow output shaft extending coaxially through the cylindrical casing supported rotatably by the casing a ring-like stator fixedly mounted on the inner surface of the cylindrical casing having piezoelectric elements fixed on the back surface thereof, a ring-like rotor mounted on the hollow output shaft and facing the front surface of the stator, and springs for pushing the rotor toward the stator. Also disclosed is a laser beam welding apparatus for welding the inner circumferential surface of a tube by using the ultrasonic motor.

Growing community of inventors

Tokyo, Japan

Toshiiku Sashida