High-torque dual-rotor stress-type longitudinal-torsion composite ultrasonic motor and its electric excitation method

Abstract

The invention discloses a high-torque double-rotor stress-type longitudinal-torsion compound ultrasonic motor and an electric excitation method, which belong to the technical field of ultrasonic motors. The motor of the invention includes a stator assembly and a rotor assembly. The stator assembly consists of friction plates, a first set of longitudinal Vibrating piezoelectric ceramics, first counterweight, first group of torsional vibration piezoelectric ceramics, flange, second group of torsional vibration piezoelectric ceramics, second counterweight, second group of longitudinal vibration piezoelectric ceramics, fastening Bolts and two radial bearings; the rotor assembly is composed of a rotating shaft, a lock nut, a spring cover, a spring, a first rotor, a key, a friction material, and a second rotor. The method of the present invention utilizes the first-order torsional vibration in the stator and the second-order longitudinal vibration in the motor as a whole, and the longitudinal vibration piezoelectric ceramic is placed near the contact surface of the stator and the rotor, that is, at the nodal plane of the longitudinal vibration, to fully excite and apply the motor longitudinal vibration. Compared with the background technology, the present invention has a larger locked-rotor torque.

Description

technical field [0001] The invention belongs to the technical field of ultrasonic motors, and in particular relates to a high-torque double-rotor stress type longitudinal-torsion compound ultrasonic motor. Background technique [0002] Ultrasonic motor is a new type of power output device that utilizes the inverse piezoelectric effect of piezoelectric ceramics and ultrasonic vibration. Compared with electromagnetic motors, it has the advantages of compact structure, high torque at low speed, fast response (millisecond level), self-locking when power is off, good position and speed control, no electromagnetic interference, and low-noise operation. Longitudinal-twisting composite ultrasonic motor is a major category of ultrasonic motors. The research on it can be traced back to the late 1980s. Up to now, there are no less than dozens of types of structures. The longitudinal-twisting composite ultrasonic motor usually contains two vibrators—a longitudinal vibrator and a torsio...

AI Technical Summary

Problems solved by technology

However, the general longitudinal-torsion composite ultrasonic motor adopts a sandwich structure to play the role of longitudinal vibration piezoelectric ceramics, which has a low utilization rate for longitudinal vibration piezoelectric ceramics.

In 1998, Ueha developed a dual-rotor longitudinal-torsion composite ultrasonic motor, which can effectively use the vibration of the longitudinal-vibration piezoelectric ceramic sheet, but the disadvantages are: first, a part of the longitudinal-vibration piezoelectric ceramic sheet is placed on the rotor The above structure makes this kind of motor must add brush structure to work, and the processing technology of the motor is complicated; secondly, because the contact occurs between the piezoelectric ceramic sheets, the manufacture of the friction pair becomes complicated and difficult

These all limit the further improvement of the motor output torque

Images