Ring structured travelling wave type contactless liquid medium ultrasonic wave electric machine

Abstract

This invention relates to a non-contacted supersonic motor including a stator, a rotor, a reversible drive circuit and a rotation speed following control device, in which, the stator is a ring post, the outside of which is set with ring piezoelectric ceramic plates and electrodes, in which, the reversible drive circuit includes a DC supply, a square wave generator, a frequency dividing phase shifter, a power amplified circuit and a transformer boosting circuit, in which, the rotation control device includes a control signal interface circuit, a controller and a motor vibration test circuit, which includes an integral phase shift circuit, a proportion amplified circuit, a subtraction circuit and a discriminating circuit.

Description

technical field [0001] The invention relates to an ultrasonic motor, which belongs to the field of micro and special motors. Background technique [0002] The ultrasonic motor uses the vibration of the stator in the ultrasonic frequency domain to drive the rotor to rotate. Its working principle is completely different from that of the electromagnetic motor, and has advantages that the electromagnetic motor does not have. According to the way of energy transfer between the stator and rotor, ultrasonic motors are divided into two types: contact type and non-contact type. The traditional contact ultrasonic motor uses the friction between the stator and the rotor to drive the rotor to move. It needs to paste wear-resistant materials on the surface of the stator and rotor, so the cost is high and the process is relatively complicated. During operation, the temperature of the stator increases due to friction, which reduces the service life of the motor, and the motor cannot run c...

AI Technical Summary

Problems solved by technology

In the existing liquid medium non-contact ultrasonic motor, the piezoelectric sheet is pasted on the upper surface of the stator ring. When the piezoelectric sheet excites the stator to vibrate, the stator not only has radial bending vibration, but also axial bending vibration. Vibration has a weak effect on the rotation of the driving rotor; on the other hand, the pasting method of the piezoelectric sheet requires the stator ring to have a certain thickness and the resonance frequency of the stator is high, while the operating frequency of the ultrasonic motor should be near the resonance frequency, and the operating frequency is high. The sampling frequency of the corresponding control system is high, which brings difficulties to the design of the high-precision control system; third, the liquid tightness in the stator ring is poor

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