Friction asymmetric inertial piezoelectric linear driving device and method

Abstract

The invention relates to a friction asymmetric inertial piezoelectric linear driving device and method, and belongs to the field of precision machinery. The driving device comprises a base unit, a driving unit and a sliding block. The driving unit is an asymmetric flexible hinge mechanism which is provided with a bridge type displacement amplification hinge and left and right pairs of driving feet with different rigidities, and is connected with the sliding block through a screw; the sliding block slides on a guide rail of the base unit; and the driving unit is installed in the U-shaped groove of the base unit in an interference fit mode. The driving method of the device comprises the steps that the rigidity of the left pair of driving feet and the rigidity of the right pair of driving feet are different, the maximum static friction force borne by the left pair of driving feet and the U-shaped groove is different, and when continuous sawtooth-shaped driving voltage is applied to a piezoelectric stack, the sliding block generates linear stepping motion based on the inertial impact principle. The device and the method have the advantages of simple structure, easiness in processing, assembly and control, capability of realizing high-speed large-stroke and high-load output, and no rollback displacement. The device and the method have good application prospects in the fields of micro-nano operation, precise instruments, precision machining and the like.

Description

technical field [0001] The invention relates to the field of precision machinery, in particular to a friction asymmetric inertial piezoelectric linear drive device and method, which can be used in the fields of precision / ultra-precision machining, precision optics and instruments, micromanipulation, biomedical engineering and the like. Background technique [0002] Drive devices with both large travel and high precision have very important applications and demands in both the scientific and industrial circles. The stepping piezoelectric precision drive device has many advantages such as high precision, fast response, simple and flexible structure, and simple control, and is widely used in precision machining and assembly, micro-nano operation, precision machinery and instruments, and other fields. Stepping piezoelectric actuators are based on different driving principles, mainly including inchworm type, stick-slip type, ultrasonic type and inertial type. Although the drivin...

AI Technical Summary

Problems solved by technology

Inchworm-type piezoelectric actuators are generally easy to achieve large output force and output displacement without retraction, but their structure and assembly are quite complicated, which limits their practical application

The structure and control of the stick-slip piezoelectric actuator are relatively simple, and the design is relatively flexible, but its output displacement has backlash and its output force is low

The ultrasonic piezoelectric drive device works in a resonance state, its design is relatively complex, and its positioning resolution and accuracy are low. At the same time, the friction and wear caused by the high-frequency contact between the rotor and the stator are serious.

The structure and control of inertial piezoelectric actuators are also relatively simple, but most of the current inertial piezoelectric actuators have problems with overturning moment and large-mass cantilever, resulting in unstable motion of the entire actuator

For example, in the literature (A low-frequency structure-control-typeinertial actuator using miniaturized bimorph piezoelectric vibrators, IEEETransactions on Industrial Electronics, 2019, 66, 6179-6188), an inertial piezoelectric actuator was designed using piezoelectric bimorph as the driving source. Although the device can achieve a large stroke, it contains a large-mass cantilever, which limits the operating frequency bandwidth of the drive device and easily causes system vibration

Literature (Inertial linearactuator driver by piezoelectric stack with changeable friction coefficients, Nanotechnology and Precision Engineering, 2008, 6(3), 190-194) adopts piezoelectric stack and mass block as power components, and designs a friction coefficient variable inertial Linear piezoelectric drive device, although the device can achieve precise drive, but the power element part of the device has a large mass block, which is prone to overturning moment during the movement process, causing system instability and affecting its output performance

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