Parallel type high-precision micro-motion device

Abstract

The invention discloses a parallel type high-precision micro-motion device which comprises a supporting base, a static platform, two same multi-connecting-rod flexible branch chains, a piezoelectric ceramic driving module, a spring pre-tightening structure, a guide structure and a micro-motion platform. A guide device is arranged between the micro-motion platform and the supporting base; each multi-connecting-rod flexible branch chain is composed of two identical upper connecting rods, a middle component and two identical lower connecting rods, and the two identical multi-connecting-rod flexible branch chains are arranged between the static platform and the micro-motion platform in parallel. The static platform and the micro-motion platform are connected through the two multi-connecting-rod flexible branch chains to form a closed structure, and the piezoelectric ceramic driving module drives the middle component to move towards the two sides and drives the upper connecting rod and the lower connecting rod to swing, so that micro-motion of the micro-motion platform is achieved. The motion zooming mechanism is adopted, so that the motion precision is improved; a spring pre-tightening structure is adopted, so that the springback rigidity is improved; a piezoelectric ceramic driving mode is adopted for driving, and the device is used for high-precision micro-motion positioning or measurement.

Description

Technical Field

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

[0002] With the development of microelectronics and optoelectronics manufacturing, precision and ultra-precision machining, and high-precision measurement in biomedical engineering, micro-motion devices are required to obtain high-precision movement and achieve high-precision operations. Therefore, the design and development of high-precision micro-motion platforms have great engineering application value.

[0003] For example, the utility model patent with publication number 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 a small space; it adopts a gapless flexible hinge with high transmission accuracy; it can achieve motion decoupling in the XY direction and complete the motion in the X direction or Y direction alone. For example, the invention patent with publication number CN102324253 A discloses a parallel micro-positioning platform and a micro-positioning platform system based on a piezoelectric ceramic driver. The micro-positioning platform adopts a parallel structure, which effectively improves the linearity of the displacement output, eliminates displacement coupling, improves the positioning accuracy, avoids the occurrence of driver separation, and protects the safety of the piezoelectric ceramic driver. Both of the above patents can achieve high-precision positioning and tracking, but the input and output are linear, there is no zoom mechanism, and the positioning accuracy of the micro-motion platform is roughly equivalent to the driving accuracy of the piezoelectric ceramic; and when rebounding, it is free rebound according to the material and structural characteristics of the mechanism, there is no pre-tightening structure, and the natural frequency is low.

[0004] For example, the invention patent with publication number CN 103225728 A discloses a piezoelectric ceramic driven two-dimensional parallel micro-motion platform. The invention adopts a two-stage amplification mechanism and a composite parallel four-bar guide mechanism, which makes the micro-motion platform compact and can achieve a high natural frequency while achieving a large stroke motion. The combination of the piezoelectric ceramic driver and the flexible hinge platform can ensure frictionless, gapless, high-precision and high-stability motion transmission. The two-dimensional parallel micro-motion platform has no pre-tightening structure, its rebound speed is low, and the natural frequency of the system is low; the two-dimensional parallel micro-motion platform achieves large-stroke precision positioning of the motion platform through an amplification mechanism, which is achieved at the expense of the positioning accuracy of its motion. Summary of the invention

[0005] The purpose of the present invention is to solve the above problems and to provide a parallel high-precision micro-motion device, which 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 the present invention is:

[0007] A parallel high-precision micro-motion device, comprising 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 on the supporting 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 provided 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, an 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 upper connecting rod and the flexible hinge connecting the micro-motion platform is equal to the distance between the upper connecting rod and the flexible hinge connecting the intermediate member; the distance between the lower connecting rod and the flexible hinge connecting the static platform is equal to the distance between the lower connecting rod and the flexible hinge connecting the intermediate member;

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

[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 member and the support base, which is used to control the rebound speed of the multi-link flexible branch chain.

[0014] Compared with the prior art, the present invention has the following significant advantages:

[0015] (1) The mechanism has a high response speed. The rebound of the traditional high-precision micro-motion device containing flexible hinges is completely based on the material and structural characteristics of the mechanism to complete free rebound, with slow response speed and poor rigidity. The present invention adds a spring preload device, the natural frequency of the system is high, and the dynamic response is faster.

[0016] (2) The multi-link flexible branch chain, 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 branch chain and micro-motion platform are cut and formed in an integrated manner, which can achieve high-precision transmission without friction or gap.

[0018] It can be seen from the above technical solution that, compared with the prior art, the present invention proposes a parallel high-precision micro-motion device having the advantages of high rigidity and high transmission accuracy, which can be used in areas such as semiconductor manufacturing, micro-electromechanical systems, nanolithography, biomedicine and measurement to achieve high-precision positioning and tracking or areas that require a fast-response micro-motion manipulator to compensate for vibration errors. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0020] Figure 2 It is the overall structural front view of the example of the present invention.

[0021] Figure 3 It 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 member, 8. guide block, 9a and 9b. upper connecting rod, 10. micro-motion platform, 11. piezoelectric ceramic, 12. piezoelectric ceramic support plate, 13. second pre-tightening bolt, 14a. first gasket, 14b. second gasket, 15. spring, 16. first pre-tightening bolt, 17. fixing bolt, 18. roller, 19. third gasket, 20. rotating shaft. DETAILED DESCRIPTION

[0023] It is easy to understand that according to the technical solution of the present invention, without changing the essential spirit of the present invention, a person skilled in the art can imagine various implementation methods of the present invention. Therefore, the following specific implementation methods and drawings are only exemplary descriptions of the technical solution of the present invention, and should not be regarded as the whole of the present invention or as a limitation or restriction of the technical solution of the present invention.

[0024] Combination Figure 1-Figure 3The present invention is 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 a fixing bolt 3, and 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, and each multi-link flexible branch consists of two identical lower links (6a and 6b), an intermediate member 7 and two identical upper links. The two upper links (9a and 9b) of each multi-link flexible branch chain are respectively connected to the micro-motion platform 10 at one end through a flexible hinge 5, and the other end of the two upper links (9a and 9b) of each multi-link flexible branch chain is respectively connected to the intermediate member 7 through a flexible hinge 5. The distance between the two upper links (9a and 9b) of each multi-link flexible branch chain and the flexible hinge 5 connecting the micro-motion platform 10 is equal to the distance between the two upper links (9a and 9b) of each multi-link flexible branch chain and the flexible hinge 5 connecting the intermediate member 7. The two upper links (9a and 9b) of each multi-link flexible branch chain are respectively connected to the micro-motion platform 10 through a flexible hinge 5. and 9b), a parallelogram mechanism is formed between the intermediate member 7 and the micro-motion platform 10; one end of the two lower links (6a and 6b) of each multi-link flexible branch chain is connected to the static platform 2 through a flexible hinge 5, and the other end of the two lower links (6a and 6b) of each multi-link flexible branch chain is connected to the intermediate member 7 through a flexible hinge 5, and the distance between the two lower links (6a and 6b) of each multi-link flexible branch chain and the flexible hinge 5 connecting the static platform 2 is equal to the distance between the two lower links (6a and 6b) of each multi-link flexible branch chain and the flexible hinge 5 connecting the intermediate member 7, and each multi-link flexible branch chain is connected to the static platform 2 through a flexible hinge 5. The two lower links (6a and 6b) of the connecting rod flexible branch chain, the intermediate member 7 and the static platform 2 form a parallelogram mechanism; the two identical multi-link flexible branches connect the upper and lower parallelogram mechanisms in series through the intermediate member 7, and the static platform 2, the two lower links (6a and 6b), the intermediate member 7, the two upper links (9a and 9b) and the micro-motion platform 10 are connected into one through the flexible hinge 5, and the angles between the upper and lower links and the static platform and between the upper and lower links and the axis of the dynamic platform are all between 3° and 10°; the multi-link flexible branch chain, the micro-motion platform, the static platform and the piezoelectric ceramic drive module form a motion scaling mechanism. The two upper links and two lower links of each multi-link flexible branch chain form a V-shaped structure with two openings facing inward.

[0025] A horizontally arranged piezoelectric ceramic drive module is installed in the middle of the two multi-link flexible branches, and 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 gasket 19; the piezoelectric ceramic 11 is placed on the piezoelectric ceramic support plate 12, and the piezoelectric ceramic support plate 12 is fixed on the intermediate member 7, and the two ends of the piezoelectric ceramic 11 are respectively connected to one end of the intermediate member 7 on the two multi-link flexible branches through the third gasket 19 and the first pre-tightening bolt 16, and the pre-tightening of the piezoelectric ceramic 11 can be completed by adjusting the first pre-tightening bolt 16; a spring pre-tightening device is installed on the corresponding support base 1 in the middle of the two multi-link flexible branches, and the spring pre-tightening device includes a spring 15, a first gasket 14a, a second gasket 14b, and a second pre-tightening bolt 13; one end of the spring 15 is connected to the intermediate member 7 on the multi-link flexible branch through the second gasket 14b (embedded in the intermediate member 7), and the other end of the spring 15 is connected to the intermediate member 7 on the multi-link flexible branch through the first gasket 1 4a is in contact with the second pre-tightening bolt 13, and the second pre-tightening bolt 13 is threadedly connected to the support base 1. The compression of the spring 15 can be adjusted by turning the bolt. The stiffness of the parallel high-precision micro-motion device can be improved by adjusting the second pre-tightening bolt 13; two identical guide devices are installed between the micro-motion platform 10 and the support base 1, and each guide device is composed 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 are provided with guide grooves to limit the micro-motion platform to move only in the vertical direction. The roller 18 is connected to the guide groove of the guide block 8 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 the fixing bolt 17. The guide device is necessary to avoid horizontal movement of the micro-motion platform 10; two identical multi-link flexible branch chains and two symmetrically arranged guide devices ensure that the flexible branch chains move symmetrically, so that the micro-motion platform 10 can 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 gasket 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, and then the lower connecting rod (6a and 6b) will swing, which will drive the upper connecting rod (9a and 9b) to swing, so that the multi-link flexible branch chain will swing at the same time, the micro-motion platform will move, and 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] The present invention utilizes a spring preload device to improve the rebound stiffness of a parallel high-precision micro-motion device; a multi-link flexible hinge, a micro-motion platform, a static platform and a piezoelectric ceramic drive module form a motion scaling mechanism, which improves its motion accuracy; the multi-link flexible branch chain, the static platform and the micro-motion platform are integrally formed and processed by wire cutting, which effectively avoids assembly errors and improves their transmission accuracy; the flexible hinge adopts an arc hinge, which is sensitive to tensile displacement and can provide a better displacement steering function, and the connection is flexible in movement; 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: It includes a supporting base, a static platform, two identical multi-link flexible branch chains, a piezoelectric ceramic drive module, a spring preload structure, a guide structure and a micro-motion platform; The static platform is fixed on the supporting base; 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 provided 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, an 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. The distance between the upper connecting rod and the flexible hinge connecting the micro-motion platform is equal to the distance between the upper connecting rod and the flexible hinge connecting the intermediate member; the distance between the lower connecting rod and the flexible hinge connecting the static platform is equal to the distance between the lower connecting rod and the flexible hinge connecting the intermediate member; A parallelogram mechanism is formed between the two upper links, the intermediate member and the micro-motion platform of each multi-link flexible branch chain; a parallelogram mechanism is formed between the two lower links, the intermediate member and the static platform of each multi-link flexible branch chain; the two upper and lower parallelogram mechanisms are connected in series through the intermediate member of the two multi-link flexible branches; the two upper links and the two lower links of each multi-link flexible branch chain form two V-shaped structures with the same openings; 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; A spring preload device is provided between the intermediate member and the support base, which is used to control the rebound speed of the multi-link flexible branch chain.

2. The parallel high-precision micro-motion device according to claim 1, characterized in that: The spring preload device includes a spring, a first gasket, a second gasket, and a second preload bolt; one end of the spring is connected to an intermediate component on the multi-link flexible branch chain through the second gasket, and the other end is in contact with the second preload bolt through the first gasket. The second preload bolt is threadedly connected to the support base. The spring compression amount can be adjusted by turning the bolt to improve the rebound speed and stiffness of the parallel high-precision micro-motion device.

3. The parallel high-precision micro-motion device according to claim 1, characterized in that: The piezoelectric ceramic drive module includes piezoelectric ceramics, a piezoelectric ceramic support plate, a first pre-tightening bolt and a third gasket; the piezoelectric ceramics are placed on a piezoelectric ceramic support plate fixed on an intermediate component, and the two ends of the piezoelectric ceramics are respectively connected to one end of the intermediate component on two multi-link flexible branches through a third gasket and a first pre-tightening bolt, and the pre-tightening of the piezoelectric ceramics is completed by adjusting the first pre-tightening bolt.

4. The parallel high-precision micro-motion device according to claim 1, characterized in that: Two guide blocks are symmetrically fixed on the support base, serving as guide devices between the micro-motion platform and the support base.

5. The parallel high-precision micro-motion device according to claim 1, characterized in that: A roller is connected in the guide groove of the guide block via a rotating shaft, and the guide block contacts the side surface of the micro-motion platform via the roller.

6. The parallel high-precision micro-motion device according to claim 1, characterized in that: The openings of the V-shaped structure are all inwards.

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