Piezoelectric inchworm driver based on space orthogonal parallel bridge type mechanism

Abstract

The invention discloses a piezoelectric inchworm driver based on a space orthogonal parallel bridge type mechanism, and relates to the technical field of precision driving and positioning, the piezoelectric inchworm driver comprises the space orthogonal parallel bridge type mechanism, the inner side of the space orthogonal parallel bridge type mechanism is provided with driving piezoelectric ceramics, and the outer side of the space orthogonal parallel bridge type mechanism is provided with a piezoelectric driving module; the space orthogonal parallel bridge type mechanism comprises a first bridge type mechanism and a second bridge type mechanism which are arranged in an orthogonal mode, and the output end of the first bridge type mechanism and the output end of the second bridge type mechanism are connected with the composite plate spring guide mechanism. The piezoelectric driving module comprises an X-direction clamping foot and a Y-direction clamping foot, bridge type amplification mechanisms are installed in the X-direction clamping foot and the Y-direction clamping foot, each bridge type amplification mechanism is provided with a downward output end, a clamping head is installed at the output end, and the clamping heads are used for making contact with the base during actuation. According to the invention, two same bridge type mechanisms are adopted to form a spatial orthogonal parallel bridge type mechanism, so that the consistency of motion performance can be ensured; and the bridge type mechanism is simpler in structure and convenient to machine.

Description

Technical Field

[0001] This invention relates to the field of precision drive and positioning technology, and in particular to a piezoelectric inchworm actuator based on a spatial orthogonal parallel bridge mechanism. Background Technology

[0002] Piezoelectric inchworm actuators, characterized by large stroke, high resolution, and high load capacity, are becoming increasingly important in precision manufacturing, nanotechnology, and other fields. Traditional dual-axis inchworm motion platforms typically consist of two actuators connected in series, resulting in a complex overall structure and driving timing circuitry. Existing technologies also include parallel inchworm actuators, such as a piezoelectric inchworm actuator comprising an orthogonally arranged bridge amplification mechanism and a composite rhombic amplification mechanism. However, this approach uses two different types of amplification mechanisms in parallel, which can easily lead to inconsistent dual-axis motion performance. Furthermore, the composite rhombic amplification mechanism has a relatively complex structure, increasing manufacturing difficulty. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the present invention aims to provide a piezoelectric grommets actuator based on a spatial orthogonal parallel bridge mechanism. By employing two identical bridge mechanisms to form a spatial orthogonal parallel bridge mechanism, the consistency of motion performance can be guaranteed, and the coupling error between the two axes in the parallel actuator can be reduced. Furthermore, the bridge mechanism structure is simpler and easier to manufacture.

[0004] To achieve the above objectives, the present invention is implemented through the following technical solution: An embodiment of the present invention provides a piezoelectric inchworm actuator based on a spatial orthogonal parallel bridge mechanism, comprising a spatial orthogonal parallel bridge mechanism, wherein a driving piezoelectric ceramic is provided on the inner side of the spatial orthogonal parallel bridge mechanism, and a piezoelectric driving module is installed on the outer side of the spatial orthogonal parallel bridge mechanism; The spatial orthogonal parallel bridge mechanism includes a first bridge mechanism and a second bridge mechanism arranged orthogonally, and the output ends of the first bridge mechanism and the second bridge mechanism are connected to a composite leaf spring guide mechanism. The piezoelectric drive module includes an X-axis clamping foot and a Y-axis clamping foot. A bridge amplification mechanism is installed in both the X-axis clamping foot and the Y-axis clamping foot. The bridge amplification mechanism has a downward output end, and a clamping head is installed at the output end. The clamping head is used to contact the base below the spatially orthogonal parallel bridge mechanism during operation.

[0005] As a further implementation, the output ends of the first bridge mechanism and the second bridge mechanism are respectively connected to the output block, and the X-axis clamping foot and the Y-axis clamping foot are connected to the corresponding output block.

[0006] As a further implementation, both the first bridge mechanism and the second bridge mechanism include two structural units arranged symmetrically with respect to the horizontal plane, and the output block is connected to the junction of the two structural units.

[0007] As a further implementation, the structural unit includes a first rigid member, one end of which is connected to a second rigid member via a flexible hinge, and the other end of which is connected to a third rigid member via a flexible hinge. The second rigid component and the third rigid component are respectively connected to the corresponding output block via flexible hinges.

[0008] As a further implementation, the bridge amplification mechanism includes a clamping piezoelectric ceramic, wherein the driving piezoelectric ceramic is arranged vertically and the clamping piezoelectric ceramic is arranged horizontally.

[0009] As a further implementation, the driving piezoelectric ceramic is fixed with a pre-tightening screw.

[0010] As a further implementation, the composite leaf spring guide mechanism is connected to the base above via a sliding assembly.

[0011] As a further implementation, the sliding component includes a first connecting plate and a second connecting plate that are parallel to each other, and linear modules are respectively connected between the first connecting plate and the base and between the first connecting plate and the second connecting plate; The composite leaf spring guide mechanism is connected to the second connecting plate via a support base.

[0012] As a further implementation, the first connecting plate has a through slot to allow space for the piezoelectric drive module to move in the Y direction, and to allow the clamping head to contact the base surface when clamping.

[0013] As a further implementation, the composite leaf spring guiding mechanism includes a decoupling unit and a connecting block. The decoupling units are symmetrically arranged on both sides of the output block, and the decoupling units between adjacent output blocks are connected by the connecting block to form an L-shaped structure.

[0014] The beneficial effects of this invention are as follows: (1) The spatial orthogonal parallel bridge mechanism of the present invention is composed of two identical bridge mechanisms. Its symmetrical structure ensures the consistency of motion characteristics of the two shafts in the driver and solves the problem of coupling error in the parallel driver. The overall structure is compact and has strong load-bearing capacity.

[0015] (2) The bridge mechanism of the present invention has two structural units that are symmetrical about the top and bottom. An output block is connected at the junction of the structural units. The output block is connected to the composite leaf spring guide mechanism. The two bridge mechanisms are located on two mutually orthogonal planes, so that the movement of the driver on the two axes is completely decoupled, ensuring that the driver will not deviate from the other direction when it moves in one direction. Moreover, the bridge mechanism is simpler and easier to process than the composite rhomboid amplification mechanism.

[0016] (3) The piezoelectric drive module of the present invention has four identical clamping feet, which are in contact with the base for clamping during operation, reducing errors in each link and ensuring motion accuracy. Attached Figure Description

[0017] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0018] Figure 1 This is a schematic diagram of the overall structure of the piezoelectric inchworm actuator according to one or more embodiments of the present invention; Figure 2 This is a perspective view of the spatial orthogonal parallel bridge mechanism according to one or more embodiments of the present invention; Figure 3(a) is a top view of the spatial orthogonal parallel bridge mechanism according to one or more embodiments of the present invention; Figure 3(b) is a side view of the spatial orthogonal parallel bridge mechanism according to one or more embodiments of the present invention; Figure 4 This is a schematic diagram of the driving piezoelectric ceramic structure according to one or more embodiments of the present invention; Figure 5 This is a schematic diagram of the movement process of the piezoelectric inchworm actuator according to one or more embodiments of the present invention; Figure 6(a) is a voltage signal diagram of driving piezoelectric ceramics according to one or more embodiments of the present invention; Figure 6(b) is a voltage signal diagram of the clamped piezoelectric ceramic according to one or more embodiments of the present invention.

[0019] Among them, 1. base, 2. sliding component, 3. piezoelectric drive module, 4. drive piezoelectric ceramic, 5. spatial orthogonal parallel bridge mechanism, 6. preload screw; 21. X-axis guide rail; 22. X-axis slider; 23. Y-axis guide rail; 24. Y-axis slider; 25. First connecting plate; 26. Second connecting plate; 51. First bridge mechanism; 52. Second bridge mechanism; 53. Composite leaf spring guide mechanism; 31. X-axis clamping foot; 32. Y-axis clamping foot; 33. Bridge amplification mechanism; 34. Clamping head; 35. Clamping piezoelectric ceramic. 511. First rigid component; 512. Second rigid component; 513. Third rigid component; 514. Flexible hinge; 515. Output block; 531. Decoupling unit; 532. Connecting block; 533. Support base. Detailed Implementation

[0020] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0021] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0022] Example 1: This embodiment provides a piezoelectric inchworm actuator based on a spatial orthogonal parallel bridge mechanism, such as Figure 1 As shown, it includes a base 1, a sliding component 2, a piezoelectric drive module 3, a driving piezoelectric ceramic 4, and a spatial orthogonal parallel bridge mechanism 5. The driving piezoelectric ceramic 4, the piezoelectric drive module 3, and the spatial orthogonal parallel bridge mechanism 5 are connected to the upper side of the base 1 through the sliding component 2.

[0023] Specifically, the sliding component 2 includes an X-axis guide rail 21, an X-axis slider 22, a Y-axis guide rail 23, a Y-axis slider 24, a first connecting plate 25, and a second connecting plate 26. The first connecting plate 25 is arranged parallel above the base 1. The bottom of the first connecting plate 25 cooperates with the X-axis guide rail 21 through the X-axis slider 22. The second connecting plate 26 is arranged above the first connecting plate 25. The second connecting plate 26 cooperates with the Y-axis guide rail 23 through the Y-axis slider 24. The piezoelectric drive module 3 is connected to the second connecting plate 26, thereby enabling the piezoelectric drive module 3 to move in the X and Y directions.

[0024] In this embodiment, the two ends of the first connecting plate 25 in the Y direction are connected to the base 1 via linear modules, and the two ends in the X direction are connected to the second connecting plate 26 via linear modules. Specifically, both ends of the first connecting plate 25 are provided with X-axis sliders 22, and the base 1 is equipped with X-axis guide rails 21 at the corresponding positions. To ensure movement stability, the first connecting plate 25 can be equipped with two or more X-axis sliders 22. Two Y-axis guide rails 23 are installed on the upper side of the first connecting plate 25, and the Y-axis guide rails 23 are located close to the edge of the first connecting plate 25. At least two Y-axis sliders 24 are installed on the bottom of the second connecting plate 26, and the Y-axis sliders 24 are slidably connected to the Y-axis guide rails 23.

[0025] In order to allow space for the installation and movement of the piezoelectric drive module 3 and the spatial orthogonal parallel bridge mechanism 5, both the first connecting plate 25 and the second connecting plate 26 in this embodiment have through slots; and the size of the second connecting plate 26 is smaller than that of the first connecting plate 25.

[0026] The spatial orthogonal parallel bridge mechanism 5 includes two bridge mechanisms located in orthogonal planes, namely the first bridge mechanism 51 and the second bridge mechanism 52, as follows: Figure 2As shown in Figures 3(a) and 3(b), the first bridge mechanism 51 and the second bridge mechanism 52 share a common central axis and are connected together. The driving piezoelectric ceramic 4 is disposed in the internal space formed by the two bridge mechanisms and is arranged vertically. The two bridge mechanisms are driven by one driving piezoelectric ceramic 4. Figure 4 As shown, one end of the driving piezoelectric ceramic 4 is bonded to the inside of the spatial orthogonal parallel bridge mechanism 5 with epoxy resin, and the other end is tightened by a preload screw 6.

[0027] For the orthogonal planes, one plane is designated as plane I, and the other as plane II. The first bridge mechanism 51, located in plane I, outputs displacement in the positive and negative X directions. The output end of the first bridge mechanism 51 extends horizontally to the left and right sides and is connected to the composite leaf spring guide mechanism 53, which is connected to the top of the second connecting plate 26 via a support base 533. The second bridge mechanism 52, located in plane II, outputs displacement in the positive and negative Y directions. The output end of the second bridge mechanism 52 extends horizontally to the front and rear sides and is connected to the composite leaf spring guide mechanism 53.

[0028] The first bridge mechanism 51 and the second bridge mechanism 52 have the same structure. This embodiment will use the first bridge mechanism 51 as an example for detailed explanation: Figure 2 As shown in Figures 3(a) and 3(b), the first bridge mechanism 51 includes two structural units that are symmetrically arranged vertically. Each structural unit includes a first rigid member 511, a second rigid member 512, and a third rigid member 513. The second rigid member 512 and the third rigid member 513 are symmetrically arranged at both ends of the first rigid member 511, and the top ends of the second rigid member 512 and the third rigid member 513 are respectively connected to the first rigid member 511 through flexible hinges 514. The bottom ends of the second rigid member 512 and the third rigid member 513 are also connected to flexible hinges 514. The corresponding second rigid members 512 and the third rigid members 513 of the two structural units are connected through corresponding output blocks 515.

[0029] Since the first bridge mechanism 51 and the second bridge mechanism 52 form an orthogonal structure, the four output blocks 515 form a cross structure; the side of the output block 515 is connected to the composite leaf spring guide mechanism 53, and the end of the output block 515 away from the bridge mechanism is connected to the piezoelectric drive module 3. In this embodiment, the output block 515 has a T-shaped structure.

[0030] like Figure 2As shown in Figure 3(a), the composite leaf spring guide mechanism 53 includes a decoupling unit 531 and a connecting block 532. The decoupling unit 531 is symmetrically arranged on both sides of each output block 515, and the decoupling unit 531 is perpendicular to the output direction of the output block 515. The decoupling units 531 between adjacent output blocks 515 are connected by the connecting block 532 to form an L-shaped structure. All decoupling units 531 constitute a rectangular frame structure. The bottom of the connecting block 532 is connected to the second connecting plate 26 through the support seat 533.

[0031] like Figure 1 As shown, the piezoelectric drive module 3 includes an X-axis clamping foot 31 and a Y-axis clamping foot 32. The X-axis clamping foot 31 is connected to the outside of the output block 515 of the first bridge mechanism 51, and the Y-axis clamping foot 32 is connected to the outside of the output block 515 of the second bridge mechanism 52. The X-axis clamping foot 31 and the Y-axis clamping foot 32 have the same structure, and each has a bridge amplification mechanism 33 on its inner side. The output end of the bridge amplification mechanism 33 is vertically downward. A clamping head 34 is fixed to the output end of the bridge amplification mechanism 33, and the clamping head 34 contacts the base 1 when clamping. A clamping piezoelectric ceramic 35 is provided inside the bridge amplification mechanism 33. In this embodiment, the two X-axis clamping feet 31 and the two Y-axis clamping feet 32 ​​have the same structure, and they clamp with the base 1 during operation, reducing design errors and ensuring motion accuracy.

[0032] In this embodiment, the clamping head 34 is fixed by epoxy resin bonding. The contact surface of the clamping head 34 is coated with a diamond film by chemical vapor deposition, and the surface of the diamond film is etched with ion beam to form horizontal lines, thereby increasing the friction of the contact surface.

[0033] Taking the X-direction as an example, the movement mode of the inchworm actuator in this embodiment is as follows: Figure 5 As shown, starting from the initial state, clamping foot 31 in the -X direction clamps, and the spatial orthogonal parallel bridge mechanism 5 extends; then clamping foot 31 in the +X direction clamps, clamping foot 31 in the -X direction releases the clamping state, the spatial orthogonal parallel bridge mechanism 5 retracts, clamping foot 31 in the +X direction releases the clamping state, and the actuator returns to the initial state, completing one motion cycle. By repeating this cycle, the unidirectional drive of the inchworm actuator can be realized.

[0034] Specifically, the working principle of this embodiment is as follows: When the actuator moves in one direction (taking the +X direction as an example), for ease of description, the clamping piezoelectric ceramic 35 in the +X direction is called clamping PZT I, and the clamping piezoelectric ceramic 35 in the -X direction is called clamping PZT II, ​​as shown in Figures 6(a) and 6(b). In the initial state, all PZTs are in the off state. The drive's operating cycle consists of six steps: Step 1: From time t0 to t1, the voltage of clamping PZT II increases from 0 to V. maxX-axis clamping foot II; Step 2: From time t1 to t2, the voltage driving the PZT (driving piezoelectric ceramic 4) increases from 0 to V0, the spatial orthogonal parallel bridge mechanism 5 expands, and pushes the +X clamping foot forward. x; Step 3: From time t2 to t3, the voltage of clamping PZT I increases from 0 to V. max X-axis clamping position, I clamping; Step 4: From time t3 to t4, the voltage of clamping PZT II changes from V... max The force drops to 0, releasing the clamping force of clamping foot II in the X direction; Step 5: From time t4 to t5, the voltage driving PZT drops from V0 to 0, the spatial orthogonal parallel bridge mechanism 5 contracts, and the X-axis clamping foot II is advanced. x; Step 6: From time t5 to t6, the clamping PZT I, clamping PZT II, ​​and driving PZT are all disconnected from the power supply, and the system returns to its initial state.

[0035] The principle of the driver moving in the Y direction is the same as that in the X direction, so it will not be repeated here.

[0036] This embodiment employs two identical bridge mechanisms connected in parallel to form a spatial orthogonal structure, exhibiting high symmetry. This ensures excellent consistency in the motion performance of the two axes of the inchworm actuator, facilitating the control of coordinated dual-axis motion. The two bridge mechanisms are located on two mutually orthogonal planes, and their deformations in their respective directions are completely decoupled. Therefore, the motion on the two axes of the inchworm actuator is also completely decoupled, ensuring that the actuator will not deviate in the other direction when moving in one direction. Furthermore, the bridge mechanism has a simple structure and is easy to manufacture.

[0037] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A piezoelectric cricket actuator based on a spatial orthogonal parallel bridge mechanism, characterized in that, It includes a spatial orthogonal parallel bridge mechanism, wherein a driving piezoelectric ceramic is provided on the inner side of the spatial orthogonal parallel bridge mechanism, and a piezoelectric driving module is installed on the outer side of the spatial orthogonal parallel bridge mechanism; The spatial orthogonal parallel bridge mechanism includes a first bridge mechanism and a second bridge mechanism arranged orthogonally, and the output ends of the first bridge mechanism and the second bridge mechanism are connected to a composite leaf spring guide mechanism. The piezoelectric drive module includes an X-axis clamping foot and a Y-axis clamping foot. A bridge amplification mechanism is installed in both the X-axis clamping foot and the Y-axis clamping foot. The bridge amplification mechanism has a downward output end, and a clamping head is installed at the output end. The clamping head is used to contact the base below the spatially orthogonal parallel bridge mechanism during operation.

2. The piezoelectric grommets actuator based on a spatial orthogonal parallel bridge mechanism according to claim 1, characterized in that, The output ends of the first bridge mechanism and the second bridge mechanism are respectively connected to the output blocks, and the X-axis clamping foot and the Y-axis clamping foot are connected to the corresponding output blocks.

3. The piezoelectric grommets actuator based on a spatial orthogonal parallel bridge mechanism according to claim 2, characterized in that, Both the first bridge mechanism and the second bridge mechanism include two structural units arranged symmetrically with respect to the horizontal plane, and the output block is connected to the junction of the two structural units.

4. A piezoelectric grommets actuator based on a spatial orthogonal parallel bridge mechanism according to claim 3, characterized in that, The structural unit includes a first rigid member, one end of which is connected to a second rigid member via a flexible hinge, and the other end of which is connected to a third rigid member via a flexible hinge. The second rigid component and the third rigid component are respectively connected to the corresponding output block via flexible hinges.

5. A piezoelectric grommets actuator based on a spatial orthogonal parallel bridge mechanism according to claim 1, characterized in that, The bridge amplification mechanism includes a clamping piezoelectric ceramic, with the driving piezoelectric ceramic arranged vertically and the clamping piezoelectric ceramic arranged horizontally.

6. A piezoelectric gaiter actuator based on a spatial orthogonal parallel bridge mechanism according to claim 1 or 5, characterized in that, The driving piezoelectric ceramic is fixed with pre-tightened screws.

7. A piezoelectric grommets actuator based on a spatial orthogonal parallel bridge mechanism according to claim 1, characterized in that, The composite leaf spring guide mechanism is connected to the base above via a sliding assembly.

8. A piezoelectric grommets actuator based on a spatial orthogonal parallel bridge mechanism according to claim 7, characterized in that, The sliding assembly includes a first connecting plate and a second connecting plate that are parallel to each other, and linear modules are respectively connected between the first connecting plate and the base and between the first connecting plate and the second connecting plate; The composite leaf spring guide mechanism is connected to the second connecting plate via a support base.

9. A piezoelectric cricket actuator based on a spatial orthogonal parallel bridge mechanism according to claim 8, characterized in that, The first connecting plate has a through slot to allow space for the piezoelectric drive module to move in the Y direction, and to allow the clamping head to contact the base surface when clamping.

10. A piezoelectric grommets actuator based on a spatial orthogonal parallel bridge mechanism according to claim 2, characterized in that, The composite leaf spring guiding mechanism includes a decoupling unit and a connecting block. The decoupling units are symmetrically arranged on both sides of the output block, and the decoupling units between adjacent output blocks are connected by the connecting block to form an L-shaped structure.

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