Parallel high-precision micro-motion device

Abstract

The application discloses a parallel high-precision micro-motion device, which comprises a supporting base, a static platform, two identical multi-link flexible support chains, a piezoelectric ceramic driving module, a spring pre-tightening structure, a guiding structure and a micro-motion platform; a guiding device is arranged between the micro-motion platform and the supporting base; each multi-link flexible support chain is composed of two identical upper links, one middle component and two identical lower links, and the two identical multi-link flexible support chains are arranged in parallel between the static platform and the micro-motion platform. The static platform and the micro-motion platform are connected through the two multi-link flexible support chains, forming a closed structure; the piezoelectric ceramic driving module drives the middle component to move to two sides, drives the upper and lower links to swing, and thus realizes the micro-motion of the micro-motion platform. The application adopts a motion scaling mechanism, improves the motion precision, adopts the spring pre-tightening structure, improves the rebound stiffness, adopts the piezoelectric ceramic driving mode, and is used for high-precision micro-motion positioning or measurement.

Description

Technical Field

[0001] This invention relates to the field of high-precision micro-motion positioning or measurement technology, and in particular to a parallel high-precision micro-motion device. Background Technology

[0002] With the development of microelectronics and optoelectronics manufacturing, precision and ultra-precision machining, and high-precision measurement in biomedical engineering, there is a need for micro-motion devices to achieve high-precision motion and realize high-precision operation. Therefore, the design and development of high-precision micro-motion platforms has significant engineering application value.

[0003] For example, the utility model patent CN 216216591 U discloses a series-type flexible two-degree-of-freedom precision motion platform, which has a compact structure and can be used for positioning or tracking needs in confined spaces; it adopts a backlash-free flexible hinge, resulting in high transmission accuracy; and it can achieve motion decoupling in the X and Y directions, independently completing motion in either the X or Y direction. Another example is the invention patent CN102324253 A, which discloses a parallel micro-positioning platform and micro-positioning platform system driven by a piezoelectric ceramic actuator. This micro-positioning platform adopts a parallel structure, effectively improving the straightness of displacement output, eliminating displacement coupling, improving positioning accuracy, avoiding actuator separation, and protecting the safety of the piezoelectric ceramic actuator. Both of these patents can achieve high-precision positioning and tracking, but the input and output are linear, without a scaling mechanism. The positioning accuracy of the micro-motion platform is roughly equivalent to the driving accuracy of the piezoelectric ceramic actuator; moreover, the rebound is free based on the material and structural characteristics of the mechanism, without a pre-tightening structure, resulting in a low natural frequency.

[0004] For example, the invention patent CN 103225728 A discloses a two-dimensional parallel micro-motion platform driven by piezoelectric ceramics. This invention employs a two-stage amplification mechanism and a composite parallel four-bar linkage, resulting in a compact micro-motion platform structure that maintains a high natural frequency while achieving large-stroke motion. The combination of the piezoelectric ceramic actuator and the flexible hinge platform ensures frictionless, backlash-free, high-precision, and high-stability motion transmission. This two-dimensional parallel micro-motion platform has no preload structure, resulting in low rebound speed and a low natural frequency. The platform achieves large-stroke precision positioning through the amplification mechanism, which is achieved at the cost of sacrificing positioning accuracy. Summary of the Invention

[0005] The purpose of this invention is to solve the above problems and provide a parallel high-precision micro-motion device. It not only improves the rebound stiffness of the device, but also includes a displacement reduction mechanism, which can achieve higher precision motion transmission, that is, the positioning accuracy of the micro-motion platform is higher than the driving accuracy.

[0006] The technical solution to achieve the purpose of this invention is as follows:

[0007] A parallel high-precision micro-motion device includes a support base, a static platform, two identical multi-link flexible branches, a piezoelectric ceramic drive module, a spring preload structure, a guide structure, and a micro-motion platform.

[0008] The static platform is fixed to the support base;

[0009] Two identical multi-link flexible branches are arranged in parallel between the static platform and the micro-motion platform. A piezoelectric ceramic drive module is located between the two multi-link flexible branches to drive the swing of the multi-link flexible branches. Each multi-link flexible branch consists of two identical upper links, one intermediate component, and two identical lower links. One end of the upper link is connected to the micro-motion platform through a flexible hinge, and the other end is connected to the intermediate component through a flexible hinge. One end of the lower link is connected to the static platform through a flexible hinge, and the other end is connected to the intermediate component through a flexible hinge.

[0010] The distance between the flexible hinge connecting the upper link and the micro-motion platform is equal to the distance between the flexible hinge connecting the upper link and the intermediate component; the distance between the flexible hinge connecting the lower link and the stationary platform is equal to the distance between the flexible hinge connecting the lower link and the intermediate component.

[0011] A parallelogram mechanism is formed between the two upper links, the intermediate component, and the micro-motion platform of each multi-link flexible branch; a parallelogram mechanism is formed between the two lower links, the intermediate component, and the static platform of each multi-link flexible branch; two multi-link flexible branches connect the upper and lower parallelogram mechanisms in series through the intermediate component; the two upper links and the two lower links of each multi-link flexible branch form two V-shaped structures with the same opening.

[0012] A guide device is provided between the micro-motion platform and the support base, so that the micro-motion platform can only move in the vertical direction;

[0013] A spring preload device is provided between the intermediate component and the support base to control the rebound speed of the multi-link flexible branch.

[0014] The significant advantages of this invention compared to existing technologies are:

[0015] (1) The mechanism has a high response speed. Traditional high-precision micro-motion devices with flexible hinges rely entirely on the material and structural characteristics of the mechanism to achieve free rebound, resulting in slow response speed and poor rigidity. The present invention incorporates a spring preload device, which increases the natural frequency of the system and makes the dynamic response faster.

[0016] (2) The multi-link flexible branch, micro-motion platform, static platform and piezoelectric ceramic drive module form a motion reduction mechanism, which improves its positioning accuracy.

[0017] (3) The static platform, multi-link flexible support chain and micro-motion platform are integrally cut and formed, which can complete high-precision transmission without friction and without gap.

[0018] As can be seen from the above technical solution, compared with the prior art, the parallel high-precision micro-motion device proposed in this invention has the advantages of high rigidity and high transmission accuracy. It can be used in fields such as semiconductor manufacturing, microelectromechanical systems, nanolithography, biomedicine and measurement to achieve high-precision positioning and tracking or to compensate for vibration errors by micro-motion manipulators that require fast response. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of an example of the present invention.

[0020] Figure 2 This is a front view of the overall structure of an example of the present invention.

[0021] Figure 3 This is a cross-sectional view of the overall structure of an example of the present invention.

[0022] Among them, 1. Support base, 2. Static platform, 3. Fixing bolt, 4. Fixing hole, 5. Flexible hinge, 6a and 6b. Lower connecting rod, 7. Intermediate component, 8. Guide block, 9a and 9b. Upper connecting rod, 10. Micro-motion platform, 11. Piezoelectric ceramic, 12. Piezoelectric ceramic support plate, 13. Second preload bolt, 14a. First washer, 14b. Second washer, 15. Spring, 16. First preload bolt, 17. Fixing bolt, 18. Roller, 19. Third washer, 20. Rotating shaft. Detailed Implementation

[0023] It is readily understood that, based on the technical solution of this invention, those skilled in the art can conceive of various embodiments of this invention without altering its essential spirit. Therefore, the following specific embodiments and accompanying drawings are merely illustrative examples of the technical solution of this invention and should not be considered as the entirety of this invention or as limitations or restrictions on its technical solution.

[0024] Combination Figures 1-3This invention relates to a parallel high-precision micro-motion device for high-precision positioning and measurement, comprising a support base 1, a static platform 2, two identical multi-link flexible branches, a piezoelectric ceramic drive module, a spring preload device, a guide structure, and a micro-motion platform 10. The static platform 2 is fixed to the support base 1 by fixing bolts 3. The static platform 2 and the micro-motion platform 10 are connected by the two multi-link flexible branches to form a closed structure. The two multi-link flexible branches are arranged symmetrically from left to right. Each multi-link flexible branch consists of two identical lower connecting rods (6a and 6b), an intermediate component 7, and two identical upper connecting rods. The system consists of rods (9a and 9b); one end of each of the two upper rods (9a and 9b) of each multi-link flexible branch is connected to the micro-motion platform 10 via flexible hinges 5, and the other end of each of the two upper rods (9a and 9b) of each multi-link flexible branch is connected to the intermediate component 7 via flexible hinges 5. The distance between the two upper rods (9a and 9b) of each multi-link flexible branch and the flexible hinges 5 connecting them to the micro-motion platform 10 is equal to the distance between the two upper rods (9a and 9b) of each multi-link flexible branch and the flexible hinges 5 connecting them to the intermediate component 7. (9b) A parallelogram mechanism is formed between the intermediate component 7 and the micro-motion platform 10; one end of each of the two lower links (6a and 6b) of each multi-link flexible branch is connected to the stationary platform 2 via a flexible hinge 5, and the other end of each of the two lower links (6a and 6b) of each multi-link flexible branch is connected to the intermediate component 7 via a flexible hinge 5. The distance between the two lower links (6a and 6b) of each multi-link flexible branch and the flexible hinge 5 connecting them to the stationary platform 2 is equal to the distance between the two lower links (6a and 6b) of each multi-link flexible branch and the flexible hinge 5 connecting them to the intermediate component 7. The two lower links (6a and 6b), the intermediate component 7, and the stationary platform 2 of the multi-link flexible branch form a parallelogram mechanism. Both identical multi-link flexible branches connect the upper and lower parallelogram mechanisms via the intermediate component 7. The stationary platform 2, the two lower links (6a and 6b), the intermediate component 7, the two upper links (9a and 9b), and the micro-motion platform 10 are connected as a whole via flexible hinges 5. The angles between the upper and lower links and the stationary platform, as well as between the links and the axis of the moving platform, are all between 3° and 10°. The multi-link flexible branch, the micro-motion platform, the stationary platform, and the piezoelectric ceramic drive module constitute a motion scaling mechanism. The two upper links and two lower links of each multi-link flexible branch form two V-shaped structures with inward-facing openings.

[0025] A horizontally arranged piezoelectric ceramic drive module is installed between two multi-link flexible branches. The piezoelectric ceramic drive module consists of a piezoelectric ceramic 11, a piezoelectric ceramic support plate 12, a first pre-tightening bolt 16, and a third washer 19. The piezoelectric ceramic 11 is placed on the piezoelectric ceramic support plate 12, which is fixed to the intermediate component 7. Both ends of the piezoelectric ceramic 11 are connected to one end of the intermediate component 7 on the two multi-link flexible branches through the third washer 19 and the first pre-tightening bolt 16, respectively. The piezoelectric ceramic 11 can be pre-tightened by adjusting the first pre-tightening bolt 16. A spring pre-tightening device is installed on the corresponding support base 1 between the two multi-link flexible branches. The spring pre-tightening device includes a spring 15, a first washer 14a, a second washer 14b, and a second pre-tightening bolt 13. One end of the spring 15 is connected to the intermediate component 7 on the multi-link flexible branch through the second washer 14b (embedded in the intermediate component 7), and the other end of the spring 15 is connected through the first washer 19. 4a contacts the second pre-tightening bolt 13, which is threadedly connected to the support base 1. Rotating the bolt adjusts the compression of the spring 15. Adjusting the second pre-tightening bolt 13 increases the rigidity of the parallel high-precision micro-motion device. Two identical guide devices are installed between the micro-motion platform 10 and the support base 1. Each guide device consists of a guide block 8, a roller 18, and a rotating shaft 20. The two guide devices are symmetrically arranged on both sides of the micro-motion platform 10 and have guide grooves to limit the micro-motion platform to move only in the vertical direction. The guide groove of the guide block 8 is connected to the roller 18 through the rotating shaft 20. The guide block 8 contacts the side of the micro-motion platform 10 through the roller 18 and is fixed to the support base 1 by fixing bolts 17. The guide devices are necessary to prevent the micro-motion platform 10 from moving horizontally. Two identical multi-link flexible chains and two symmetrically arranged guide devices ensure that the flexible chains move symmetrically, allowing the micro-motion platform 10 to move smoothly in the vertical direction.

[0026] The working principle of this example is that the output end of the piezoelectric ceramic 11 drives the intermediate component 7 to move through the third washer 19 and the first pre-tightening bolt 16. The movement of the intermediate component 7 will drive the lower connecting rod (6a and 6b) to swing. Then, the swing of the lower connecting rod (6a and 6b) will drive the upper connecting rod (9a and 9b) to swing, so that the multi-link flexible chain swings at the same time, and the micro-motion platform will move. Then, under the action of the spring pre-tightening device, the rebound speed and rigidity of the parallel high-precision micro-motion device are improved.

[0027] This invention utilizes a spring preload device to improve the rebound stiffness of the parallel high-precision micro-motion device; a multi-link flexible hinge, micro-motion platform, static platform, and piezoelectric ceramic drive module form a motion scaling mechanism, improving its motion accuracy; the multi-link flexible support, static platform, and micro-motion platform are integrally formed by wire cutting, effectively avoiding assembly errors and improving its transmission accuracy; the flexible hinge adopts an arc hinge, which is sensitive to tensile displacement and can provide good displacement steering function, and the connection point moves flexibly; the symmetrically arranged guide device guides the movement of the micro-motion platform of the system.

Claims

1. A parallel high-precision micro-motion device, characterized in that, The parallel high-precision micro-motion device comprises a support base, a static platform, two identical multi-link flexible support chains, a piezoelectric ceramic driving module, a spring pre-tightening structure, a guide structure and a micro-motion platform. The static platform is fixed on the support base. The two identical multi-link flexible support chains are arranged in parallel between the static platform and the micro-motion platform, and a piezoelectric ceramic driving module is arranged in the middle of the two multi-link flexible support chains and used for driving the swing of the multi-link flexible support chains. Each multi-link flexible support chain is composed of two identical upper links, a middle component and two identical lower links. The distance between the flexible hinges, through which the upper links are connected with the micro-motion platform, is equal to the distance between the flexible hinges, through which the upper links are connected with the middle component. The distance between the flexible hinges, through which the lower links are connected with the static platform, is equal to the distance between the flexible hinges, through which the lower links are connected with the middle component. The two upper links, the middle component and the micro-motion platform of each multi-link flexible support chain form a parallelogram mechanism.

2. The parallel type high-precision micromotion device according to claim 1, wherein The two lower links, the middle component and the static platform of each multi-link flexible support chain form a parallelogram mechanism.

3. The parallel type high-precision micromotion device according to claim 1, wherein The two parallelogram mechanisms of each multi-link flexible support chain are connected in series through the middle component.

4. The parallel kinematic high precision micropositioning apparatus according to claim 1, characterized in that The two upper links and the two lower links of each multi-link flexible support chain form two V-shaped structures with consistent openings.

5. The parallel kinematic high precision micropositioning apparatus according to claim 4, characterized in that A guide device is arranged between the micro-motion platform and the support base, so that the micro-motion platform can only move in the vertical direction.

6. The parallel kinematic high precision micropositioning apparatus according to claim 1, characterized in that A spring pre-tightening device is arranged between the middle component and the support base, and used for controlling the rebound speed of the multi-link flexible support chain. The spring pre-tightening device comprises a spring, a first gasket, a second gasket and a second pre-tightening bolt. One end of the spring is in contact with the middle component of the multi-link flexible support chain through the second gasket, and the other end of the spring is in contact with the second pre-tightening bolt through the first gasket. The second pre-tightening bolt is threadedly connected with the support base. The piezoelectric ceramic driving module comprises a piezoelectric ceramic, a piezoelectric ceramic support plate, a first pre-tightening bolt and a third gasket. The piezoelectric ceramic is placed on the piezoelectric ceramic support plate fixed on the middle component. The two ends of the piezoelectric ceramic are connected with one end of the middle component of the two multi-link flexible support chains through the third gasket and the first pre-tightening bolt. The first pre-tightening bolt is used for pre-tightening the piezoelectric ceramic. Two guide blocks are symmetrically fixed on the support base and used as the guide device between the micro-motion platform and the support base. Rollers are connected with the guide grooves of the guide blocks through rotating shafts. The micro-motion platform is in contact with the side surface of the guide blocks through the rollers. The openings of the V-shaped structures are all inward.

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