Asmo Co., Ltd.

Shinichi Naito

Hiroyuki Furukoshi

Yoshihiro Adachi

Satoshi Morizaki

When a motor is driven by a signal transmitted due to a switch turned on, a count value is added. When the motor is stopped, the count value is subtracted. When the count value is an upper limit value, the motor is continuously driven until the switch is changed to an off state. Subsequently, until the count value comes to a lower limit value, the motor is maintained in a stopped state even if the switch of the motor is changed to an on state. For this reason, generation of heat in the motor can be prevented.

Driving circuit of a motor

An ultrasonic motor includes a rotor and a rotor accommodated in a housing. The stator includes a piezoelectric element and the housing is secured to a base by screws. The rotor contacts the stator. The piezoelectric element vibrates the stator to rotate the rotor. An insulation plate is located between the stator and the base. An insulation washer is located between the stator and each screw. A rotary shaft is rotatably supported by the housing. The rotary shaft is coupled to the rotor with an insulation collar in between. Therefore, the stator and the rotor are electrically insulated from the housing and the rotary shaft. This arrangement reduces electromagnetic noise, which interferes with other electric devices, such as radios.

Growing community of inventors

Toyohashi, Japan

Shinichi Naito