CN110912447B - Piezoelectric rotary driving platform based on crawling principle - Google Patents

Abstract

The invention relates to a piezoelectric rotary drive platform based on the crawling principle. The platform is mainly composed of two sets of piezoelectric drive units, spring washers, rotors, pre-tightening nuts, screw shafts, screws and bases, among which the piezoelectric drive units include piezoelectric stacks, pre-tightening wedges, thin-walled flexible hinges mechanism. Two sets of thin-walled flexible hinge mechanisms can realize parasitic inertial motion; two piezoelectric stacks are respectively obliquely installed in the two thin-walled flexible hinge mechanisms, and the rotor is realized through the parasitic inertial motion of the two sets of thin-walled flexible hinge mechanisms. rotary drive. The present invention adopts two groups of driving units to carry out sequential control on the two groups of voltages, and the two groups of driving units work alternately, which can eliminate back-off phenomenon and improve output performance. The platform can realize high-efficiency rotary motion, and can be applied to precision ultra-precision machining, micro-electromechanical systems, micro-manipulation robots, large-scale integrated circuit manufacturing, and biotechnology fields.

Description

A Piezoelectric Rotary Drive Platform Based on Crawling Principle

technical field

The invention relates to the fields of precision ultra-precision machining, micro-nano manipulating robots, and micro-electromechanical system engineering, and in particular to a piezoelectric rotary drive platform based on the crawling principle.

Background technique

Precision drive technology with micro/nano-level positioning accuracy is a key technology in high-tech fields such as ultra-precision machining and measurement, optical engineering, modern medical care, and aerospace technology. In order to achieve micro/nanometer output precision, the application of modern precision drive technology puts forward higher requirements for the precision of the drive platform. The traditional driving platform has low output precision and large overall size, which cannot meet the requirements of micro/nano-level high precision and small size of the driving platform in the precision system of modern advanced technology. Piezoelectric ceramic drivers have the advantages of small size, high displacement resolution, large output load, high energy conversion rate, etc., and can achieve micro/nano-level output accuracy, and have been increasingly used in micro-positioning and precision ultra-precision machining middle. The existing parasitic piezoelectric drive platform will back off during the motion, which greatly reduces the output performance of the platform. Therefore, it is necessary to design a high-efficiency piezoelectric drive platform that can eliminate the back-off phenomenon and increase the output load of the piezoelectric drive platform.

Contents of the invention

The object of the present invention is to provide a piezoelectric rotary drive platform based on the crawling principle, which solves the above-mentioned problems in the prior art. The invention has the characteristics of simple and compact structure, high output precision, large output rigidity and output load, and high output frequency, and can eliminate the retreat phenomenon at the same time, and realize the high-efficiency rotary motion output function.

Above-mentioned purpose of the present invention is achieved through the following technical solutions:

A piezoelectric rotary drive platform based on the principle of crawling, including two sets of piezoelectric drive units, spring washers, rotors, pre-tightening nuts, screw shafts, screws and bases, the piezoelectric drive unit includes pre-tightening wedges, piezoelectric stacks The pile and thin-walled flexible hinge mechanism is characterized in that: the platform adopts the principle of parasitic inertia to alternately drive two sets of drive units to realize the precise drive of the rotary motion. The thin-walled flexible hinge mechanism has a semi-cylindrical shape, the upper and lower end surfaces are semicircular, and the upper and lower end surfaces are provided with a table for installing piezoelectric stacks. The upper and lower end surfaces are connected by two side columns, and the two ends of the side columns It is a thin-wall flexible hinge. The piezoelectric stack is placed obliquely in the thin-wall flexible hinge mechanism. Under voltage control, the piezoelectric stack elongates and drives the flexible hinge mechanism to perform parasitic inertial motion. At the same time, it provides a thin-wall flexible hinge The pre-tightening force between the mechanism and the rotor and the driving force for the rotation of the rotor.

The platform provides the driving voltage alternately by controlling the timing of two groups of piezoelectric driving units. When only one group of piezoelectric driving units is working, the piezoelectric stacks in this group are energized, and the piezoelectric stacks slowly elongate. The flexible hinge mechanism in this group does parasitic inertial motion to push the rotor to rotate; when this group of piezoelectric stacks is about to be de-energized, the piezoelectric stacks in the other group of piezoelectric drive units are energized and slowly elongate, driving another The flexible hinge mechanism in the group makes parasitic inertial motion to push the rotor to continue to rotate. In this process, when the piezoelectric stack returns to the initial position after power failure, the flexible hinge mechanism also returns to the initial state, and the rotor keeps the angle after rotation under the action of inertia. This alternate driving method can eliminate the retreat phenomenon of the rotor during the motion cycle, and at the same time greatly increase the output load and improve the output performance.

The thin-walled flexible hinge mechanism is installed on the base through screws; the piezoelectric stack can be preloaded through a preload wedge; the preload nut can adjust the initial preload between the thin-walled flexible hinge mechanism and the rotor ;

The piezoelectric stack adopts a shape-controllable piezoelectric ceramic stack PZT, and the piezoelectric signal adopts a piezoelectric signal in the form of a sawtooth wave or a triangular wave to control the piezoelectric stack in time sequence, so that the piezoelectric stack slows down in time sequence. Elongate, push the flexible hinge mechanism to do parasitic inertial motion alternately, so as to realize the rotary motion of the rotor.

The main advantage of the present invention is that: using the principle of parasitic inertial motion, two groups of piezoelectric drive units are used to work alternately according to time sequence, eliminating the retreat phenomenon during the motion process. The invention greatly increases the output load of the driving platform, realizes the rotary motion of the rotor at the same time, and has the advantages of high driving reliability, good stability, high working efficiency and the like. It can be used in important scientific and engineering fields such as precision ultra-precision machining, micro-manipulation robots, micro-electro-mechanical systems, large-scale integrated circuit manufacturing, and biotechnology. The invention has the advantages of simple structure, compact layout, stable movement, high efficiency, low investment, high benefit, and broad application prospects.

Description of drawings

Fig. 1 is a schematic diagram of an isometric view of the present invention;

Fig. 2 is a front schematic view of the present invention;

Fig. 3 is a schematic isometric view of the flexible hinge mechanism of the present invention;

Fig. 4 is a schematic front view of the flexible hinge mechanism of the present invention.

In the picture:

1. Spring washer; 2. Preload wedge I; 3. Piezoelectric stack I; 4. Flexible thin-walled hinge mechanism I; 5. Rotor; 6. Preload nut; 7. Screw shaft; 8. Preload Tight wedge II; 9. Piezoelectric stack II; 10. Thin-wall flexible hinge mechanism II; 11. Screws; 12. Base.

Detailed ways

Referring to shown in Fig. 1 to Fig. 4, concrete work process of the present invention is as follows:

Realization of rotor rotation, initial state: adjust the pre-tightening nut (6) to control the initial pre-tightening force between the thin-walled flexible hinge mechanism I, II (4, 10) and the rotor (5); use sawtooth or triangular wave Form piezoelectric signals control piezoelectric stacks I, II (3, 9). When the piezoelectric stacks I, II (3, 9) are not charged, the system is in a free state; when only the piezoelectric stack I (3) is energized, it elongates through the inverse piezoelectric effect and pushes the thin-walled flexible hinge mechanism I (4) Deformation, the thin-walled flexible hinge mechanism I (4) presses the rotor (5), and the thin-walled flexible hinge mechanism I (4) drives the rotor (5) under the action of static friction with the rotor (5) Rotation; when the piezoelectric stack I (3) is about to lose power, the piezoelectric stack II (9) is electrically extended, pushing the thin-walled flexible hinge mechanism II (10) to deform, and the thin-walled flexible hinge mechanism II ( 10) Compress the rotor (5), and drive the rotor (5) to continue to rotate under the action of static friction with the rotor (5). When the piezoelectric stack II (9) is about to lose power, the piezoelectric stack I (3) is electrically extended again, driving the thin-walled flexible hinge mechanism I (4) to do parasitic inertial motion and start the next cycle of motion cycle. In this process, when the piezoelectric stack I (3) loses power and quickly returns to the initial position, the flexible hinge mechanism I (4) also returns to the initial state. Similarly, when the piezoelectric stack II (9) loses power and quickly returns to the initial position, the flexible hinge mechanism II (10) also returns to the initial state. By repeating the above process, the driving platform can realize high-efficiency rotary motion and obtain a larger output rotary angle.

Claims (1)

1. A piezoelectric rotary drive platform based on the principle of crawling, including two sets of piezoelectric drive units, spring washers, rotors, pre-tightening nuts, screw shafts, screws and bases, the piezoelectric drive unit includes pre-tightening wedges, pressure Electrically stacked, thin-walled flexible hinge mechanism, characterized in that: the platform utilizes the principle of parasitic inertia to alternately drive two sets of drive units to realize the precise drive of rotational motion; the thin-walled flexible hinge mechanism is in a semi-cylindrical shape, The upper and lower end surfaces are semicircular, and the upper and lower end surfaces are provided with a platform for installing piezoelectric stacks. The upper and lower end surfaces are fixed by two side columns, and the two ends of the side columns are thin-walled flexible hinges. The piezoelectric stack is placed obliquely on the In the thin-walled flexible hinge mechanism, the piezoelectric stack is elongated under voltage control, driving the flexible hinge mechanism to perform parasitic inertial motion, and at the same time providing the pre-tightening force between the thin-walled flexible hinge mechanism and the rotor and the driving force for the rotor rotation ; The platform provides the driving voltage alternately by controlling the timing of two groups of piezoelectric driving units. The flexible hinge mechanism in this group does parasitic inertial motion to push the rotor to rotate; when this group of piezoelectric stacks is about to be de-energized, the piezoelectric stacks in the other group of piezoelectric drive units are energized and slowly elongate, driving another The flexible hinge mechanism in the group does parasitic inertial motion to push the rotor to continue to rotate; in this process, when the piezoelectric stack returns to the initial position after power failure, the flexible hinge mechanism also returns to the initial state, and the rotor keeps rotating under the action of inertia. The angle does not move.

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