Rotary Ultrasonic Motor Driven by Single Electric Signal

Abstract

The invention discloses a single-electric-signal driving rotating ultrasonic motor. The single-electric-signal driving rotating ultrasonic motor comprises mandrels, rear cover plates, piezoelectric ceramic pieces, electrode plates, elliptical vibration mode converters, a friction plate, a bearing, a spring and a nut, wherein a stator of the ultrasonic motor is composed of each mandrel, each rear cover plate, each piezoelectric ceramic piece, each electrode plate and each elliptical vibration mode converter, a rotor of the ultrasonic motor is composed of the friction plate and the bearing, a positive-pressure prestressing force adjusting mechanism of the stators and the rotor is composed of the spring and the nut. Through the structure of the elliptic vibration mode converter with the special design, the elliptic track motion of mass points on a driving tooth end face of each stator is achieved through longitudinal vibration of the piezoelectric ceramic pieces, and the rotor is driven to rotate. The single-electric-signal driving rotating ultrasonic motor has the advantages of being simple in structure, easy to manufacture, prone to microminiaturization and integration, low in cost, low in control difficulty and wide in application prospect.

Description

technical field [0001] The invention relates to the field of ultrasonic motors utilizing the inverse piezoelectric effect of piezoelectric ceramics, in particular to a rotary ultrasonic motor driven by a single electric signal. Background technique [0002] The rotary ultrasonic motor is a new type of micro-motor developed and applied rapidly in the 1980s. It is an electromechanical coupling device that uses the inverse piezoelectric effect of piezoelectric materials to convert electrical energy to mechanical energy. Through the friction between the stator and the rotor, the The micro-vibration of the elastomer is converted into the macro-rotational motion of the rotor, which directly pushes the load. In the existing rotary ultrasonic motors, there are generally problems such as small driving torque, large axial volume, large wear difference between the inner and outer diameter contact areas of the stator and rotor, and low working reliability. [0003] The mode conversion ...

AI Technical Summary

Problems solved by technology

Although the motor has the advantages of large output torque, etc., its structure is complicated, and the screw movement (rotation force) of the compression nut during the compression process of the piezoelectric ceramic sheets is very easy to cause misalignment between the piezoelectric ceramic sheets, which is difficult to achieve. The technical requirement to ensure a 60-degree misalignment between adjacent piezoelectric ceramic sheets; in addition, there is no positioning device between the stator and the rotor of the motor, which affects the accuracy of the contact position between the stator and the rotor, thereby affecting the motor. Stability of torque and speed; this type of rotating ultrasonic motor has complex structure, difficult manufacturing and installation, high cost, poor stability of motor torque and speed, etc.

Images