A single-layer two-degree-of-freedom inchworm driver and driving method

Abstract

The present invention discloses a single-layer inchworm actuator with two degrees of freedom and a driving method, which includes a fixed platform. Inside the fixed platform, there are an X-direction moving platform and a Y-direction moving platform, and the X-direction moving platform and the Y-direction moving platform are located in the same plane. The X-direction moving platform includes a frame, and the frame includes a partition frame. On both sides of the partition frame, there are a first clamping mechanism and a second clamping mechanism respectively. The first clamping mechanism and the second clamping mechanism can respectively clamp with the fixed platform. The first clamping mechanism is connected to the partition frame through a first driving mechanism. An installation groove is provided inside the partition frame, and the Y-direction moving platform is located in the installation groove. The Y-direction moving platform includes a second driving mechanism, and on both sides of the second driving mechanism, there are third clamping mechanisms connected, and the third clamping mechanisms can clamp with the inner wall of the installation groove. By installing the X-direction moving platform and the Y-direction moving platform located in the same plane inside the fixed platform, the present invention can realize the function of a single layer with two degrees of freedom, with small volume, light weight, low cost, and convenient assembly.

Description

Technical Field

[0001] The present invention relates to the technical field of linear motors, and more specifically, to a single-layer two-degree-of-freedom inchworm driver and a driving method thereof. Background Art

[0002] In many fields such as precision and ultra-precision machining, optical engineering, etc., the demand for large-stroke and high-precision motors is increasing rapidly. Traditional linear motors can achieve large strokes, but it is difficult to achieve high resolution. Piezoelectric inchworm motors have received more and more attention due to their large output force and high motion accuracy;

[0003] The piezoelectric inchworm driver is designed based on the crawling principle of the animal inchworm in nature, and realizes linear motion by adopting the method of "clamping - driving - clamping". The current single-layer piezoelectric inchworm driver can only achieve single-degree-of-freedom motion. If two-degree-of-freedom or multi-degree-of-freedom motion is to be achieved, only a double-layer or multi-layer structure can be used. This multi-degree-of-freedom inchworm driver usually superimposes two single-degree-of-freedom piezoelectric inchworm drivers to generate motion along two axes. However, this method not only increases its own volume, cannot meet the requirements of high precision and small volume, has a small application range, but also has a cumbersome assembly, increases the manufacturing cost and weight. Therefore, it is urgent to improve this situation. Summary of the Invention

[0004] The purpose of the present invention is to overcome the above-mentioned deficiencies of the prior art, and provide a single-layer two-degree-of-freedom inchworm driver and a driving method thereof. By installing the X-direction moving platform and the Y-direction moving platform on the same plane in the fixed platform, the function of single-layer two-degree-of-freedom can be realized, and it has the advantages of small volume, light weight, low cost and convenient assembly.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions: A single-layer two-degree-of-freedom inchworm driver includes a fixed platform, and an X-direction moving platform and a Y-direction moving platform are arranged inside the fixed platform, and the X-direction moving platform and the Y-direction moving platform are located on the same plane;

[0006] The X-direction moving platform includes a frame, the frame includes a partition frame, a first clamping mechanism and a second clamping mechanism are respectively arranged on both sides of the partition frame, the first clamping mechanism and the second clamping mechanism can respectively clamp with the fixed platform, the first clamping mechanism is connected with the partition frame through a first driving mechanism, an installation groove is arranged inside the partition frame, and the Y-direction moving platform is located inside the installation groove;

[0007] The Y-direction moving platform includes a second driving mechanism, and third clamping mechanisms are connected to both sides of the second driving mechanism, and the third clamping mechanisms can clamp with the inner wall of the installation groove.

[0008] Furthermore, the number of the first clamping mechanisms is two. The two first clamping mechanisms are connected by a first connecting block, and the first connecting block is connected to the partition frame by a first driving mechanism.

[0009] Furthermore, the first driving mechanism includes a first piezoelectric stack. Flexible folding beams are arranged on both sides of the first piezoelectric stack. The two ends of the first piezoelectric stack and the flexible folding beams are respectively connected to the first connecting block and the partition frame. When the first piezoelectric stack expands and contracts, it can drive the first clamping mechanism to move in the X direction.

[0010] Furthermore, the first clamping mechanism includes a second piezoelectric stack and a clamping block. First rigid blocks are fixed at both ends of the second piezoelectric stack. The first rigid blocks are flexibly connected to the first connecting block through a first flexible plate, and the first rigid blocks are flexibly connected to the clamping block through a second flexible plate. When the second piezoelectric stack expands and contracts, it can drive the clamping block to move away from or abut against the inner wall of the fixed platform.

[0011] Furthermore, the number of the second clamping mechanisms is two. The two second clamping mechanisms are connected by a second connecting block. The second clamping mechanism includes a third piezoelectric stack and a third connecting block. Second rigid blocks are fixed at both ends of the third piezoelectric stack. The two ends of the third connecting block are connected to the two second rigid blocks through a third flexible plate. The side of the second rigid block far away from the third connecting block is connected to the partition frame through a third flexible plate. When the third piezoelectric stack expands and contracts, the second rigid block located on the outside can abut against or disengage from the inner wall of the fixed platform.

[0012] Furthermore, there is a gap between the second driving mechanism and the inner wall of the partition frame. The second driving mechanism includes an amplifying mechanism and a fourth piezoelectric stack located inside the amplifying mechanism. The two sides of the amplifying mechanism are respectively connected to two third clamping mechanisms. When the fourth piezoelectric stack expands and contracts, it can drive the amplifying mechanism to move, so that the third clamping mechanism moves in the Y direction.

[0013] Furthermore, the amplifying mechanism includes third rigid blocks fixed at both ends of the fourth piezoelectric stack and amplifying units located on both sides of the fourth piezoelectric stack. The two ends of the amplifying unit are respectively flexibly connected to the two third rigid blocks, and the two amplifying units are respectively connected to the two third clamping mechanisms.

[0014] Furthermore, the amplifying mechanism is an elliptical amplifying mechanism. The amplifying unit includes a fourth connecting block and fourth rigid blocks located on both sides of the fourth connecting block. The fourth connecting block is flexibly connected to the fourth rigid blocks on both sides through a fifth flexible plate. The two fourth rigid blocks in the same amplifying unit are respectively connected to the two third rigid blocks through a fourth flexible plate.

[0015] Further, the third clamping mechanism includes a fifth piezoelectric stack and fifth connecting blocks located on both sides of the fifth piezoelectric stack. Fifth rigid blocks are fixed at both ends of the fifth piezoelectric stack. The two ends of the fifth connecting blocks are flexibly connected to the fifth rigid blocks at both ends of the fifth piezoelectric stack through sixth flexible plates. One side of the fifth connecting block is connected to the fourth connecting block. When the fifth piezoelectric stack expands and contracts, the fifth rigid block can movably abut against or disengage from the inner wall of the installation groove.

[0016] A driving method for a single-layer two-degree-of-freedom inchworm driver includes the following steps:

[0017] S1. Energize the fifth piezoelectric stack of a third clamping mechanism. The fifth piezoelectric stack elongates when energized. This third clamping mechanism clamps the separation frame. At the same time, cut off the power supply to the second piezoelectric stack of the first clamping mechanism, and the first clamping mechanism clamps with the fixed platform;

[0018] S2. Energize the first piezoelectric stack of the first driving mechanism and the fourth piezoelectric stack of the second driving mechanism. The separation frame and the second clamping mechanism move one step in the X direction, and another third clamping mechanism and the second driving mechanism move one step in the Y direction to achieve movement in the X and Y directions;

[0019] S3. Energize the third piezoelectric stack of the second clamping mechanism and the fifth piezoelectric stack of the third clamping mechanism in step S2 to make them elongate. The second clamping mechanism clamps the fixed platform, and this third clamping mechanism clamps the separation frame;

[0020] S4. Cut off the power supply to the fifth piezoelectric stack of the third clamping mechanism in step S1. This third clamping mechanism separates from the separation frame. At the same time, energize the second piezoelectric stack of the first clamping mechanism, and the first clamping mechanism separates from the fixed platform;

[0021] S5. Cut off the power supply to the first piezoelectric stack of the first driving mechanism and the fourth piezoelectric stack of the second driving mechanism. The first clamping mechanism moves one step in the X direction, and the third clamping mechanism in step S1 and the second driving mechanism move one step in the Y direction to achieve movement in the X and Y directions again;

[0022] S6. Repeat steps S1 - S5 to achieve continuous output of displacements in the X and Y directions.

[0023] In summary, the present invention has the following beneficial effects:

[0024] When the first clamping mechanism clamps with the inner wall of the fixed platform and the second clamping mechanism disengages from the fixed platform, the first driving mechanism can push the separation frame, the Y-direction moving platform, and the second clamping mechanism to move one step to the right; when the first clamping mechanism disengages from the fixed platform and the second clamping mechanism clamps with the inner wall of the fixed platform, the first driving mechanism can pull the first clamping mechanism to move one step to the right to achieve movement in the X direction;

[0025] When the current third clamping mechanism clamps with the inner wall of the installation groove and the upper third clamping mechanism disengages from the inner wall of the installation groove, the second driving mechanism and the upper third clamping mechanism move down one step; when the current third clamping mechanism disengages from the inner wall of the installation groove and the upper third clamping mechanism clamps with the inner wall of the installation groove, the second driving mechanism and the lower third clamping mechanism move down one step to achieve Y-direction movement;

[0026] By setting the X-direction moving platform and the Y-direction moving platform, the activities of X and Y degrees of freedom can be achieved. And by setting the X-direction moving platform and the Y-direction moving platform on the same plane, the activities of single-layer two degrees of freedom can also be achieved, greatly reducing the overall volume. Thus, it can meet the requirements of high precision, small volume and light weight, and can be applicable to the usage needs of more small-volume, high-precision and multi-degree-of-freedom devices. Moreover, it also has the advantages of simple structure, easy production and low production cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is the structural schematic diagram of this embodiment;

[0028] Figure 2 is the top view of this embodiment;

[0029] Figure 3 is the structural schematic diagram of the X-direction moving platform;

[0030] Figure 4 is the structural schematic diagram of the Y-direction moving platform;

[0031] Figure 5 is the schematic diagram of the displacement amplification mechanism;

[0032] Figure 6 is the piezoelectric stack drive voltage signal diagram;

[0033] Figure 7 is the displacement amplification analysis diagram of the displacement amplification mechanism;

[0034] Figure 8 is the maximum stress analysis diagram of the displacement amplification mechanism;

[0035] Figure 9 is the natural frequency analysis diagram of the displacement amplification mechanism.

[0036] Reference numerals: 1, fixed platform; 2, frame; 21, partition frame; 22, first connecting block; 23, mounting groove; 24, second connecting block; 3, first driving mechanism; 31, first piezoelectric stack; 32, flexible folding beam; 4, first clamping mechanism; 41, second piezoelectric stack; 42, first rigid block; 43, first flexible plate; 44, clamping block; 45, second flexible plate; 5, second clamping mechanism; 51, third piezoelectric stack; 52, second rigid block; 53, third connecting block; 54, third flexible plate; 6, second driving mechanism; 61, fourth piezoelectric stack; 62, third rigid block; 63, fourth flexible plate; 64, fourth rigid block; 65, fifth flexible plate; 66, fourth connecting block; 7, third clamping mechanism; 71, fifth piezoelectric stack; 72, fifth rigid block; 73, fifth connecting block; 74, sixth flexible plate. Detailed implementation mode

[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0038] As Figures 1 to 9 As shown, this embodiment discloses a single-layer two-degree-of-freedom inchworm driver, including a fixed platform 1. An X-direction moving platform and a Y-direction moving platform are arranged inside the fixed platform 1. The X-direction moving platform and the Y-direction moving platform are in the same plane. Specifically, the X-direction moving platform includes a frame 2. The frame 2 includes a partition frame 21. A first clamping mechanism 4 and a second clamping mechanism 5 are respectively arranged on both sides of the partition frame 21. The first clamping mechanism 4 and the second clamping mechanism 5 can respectively clamp with the fixed platform 1. The first clamping mechanism 4 is connected to the partition frame 21 through a first driving mechanism 3. An installation groove 23 is arranged inside the partition frame 21. The Y-direction moving platform is located inside the installation groove 23. The Y-direction moving platform includes a second driving mechanism 6. Third clamping mechanisms 7 are connected to both sides of the second driving mechanism 6. The third clamping mechanisms 7 can clamp with the inner wall of the installation groove 23. The two third clamping mechanisms 7 are respectively an upper third clamping mechanism 7 located above the second driving mechanism 6 and a lower third clamping mechanism 7 located below the second driving mechanism 6. The upper and lower third clamping mechanisms 7 can respectively clamp with the inner wall of the installation groove 23.

[0039] As Figure 2As shown in the figure, when the first clamping mechanism 4 clamps with the inner wall of the fixed platform 1 and the second clamping mechanism 5 disengages from the fixed platform 1, the first driving mechanism 3 can push the partition frame 21, the Y-direction moving platform and the second clamping mechanism 5 to move one step to the right; when the first clamping mechanism 4 disengages from the fixed platform 1 and the second clamping mechanism 5 clamps with the inner wall of the fixed platform 1, the first driving mechanism 3 can pull the first clamping mechanism 4 to move one step to the right to achieve X-direction movement;

[0040] When the lower third clamping mechanism 7 clamps with the inner wall of the installation groove 23 and the upper third clamping mechanism 7 disengages from the inner wall of the installation groove 23, the second driving mechanism 6 and the upper third clamping mechanism 7 move one step downward; when the lower third clamping mechanism 7 disengages from the inner wall of the installation groove 23 and the upper third clamping mechanism 7 clamps with the inner wall of the installation groove 23, the second driving mechanism 6 and the lower third clamping mechanism 7 move one step downward to achieve Y-direction movement;

[0041] By setting the X-direction moving platform and the Y-direction moving platform, activities in the X and Y degrees of freedom can be achieved. And by arranging the X-direction moving platform and the Y-direction moving platform in the same plane, activities with two automatic degrees in a single layer can also be achieved, greatly reducing the overall volume. Thus, the requirements of high precision, small volume and light weight can be met, and it can be applied to the usage requirements of more small-volume, high-precision and multi-degree-of-freedom devices. Moreover, it also has the advantages of simple structure, easy production and low production cost.

[0042] As Figure 2 and Figure 3 As shown in the figure, the number of the first clamping mechanisms 4 is two. The two first clamping mechanisms 4 are connected by a first connecting block 22. The first connecting block 22 is a rigid part. The first connecting block 22 is connected with the partition frame 21 through the first driving mechanism 3. Specifically, the first driving mechanism 3 includes a first piezoelectric stack 31. Flexible folding beams 32 are arranged on both sides of the first piezoelectric stack 31. The flexible folding beams 32 are flexible thin sheets that can be stretched or contracted. The two ends of the first piezoelectric stack 31 and the flexible folding beams 32 are respectively connected with the first connecting block 22 and the partition frame 21. One end of the first piezoelectric stack 31 is fixed to the middle of the first connecting block 22, and the other end is fixed to the middle of the partition frame 21. When the first piezoelectric stack 31 expands and contracts, it can drive the first clamping mechanism 4 to move in the X direction;

[0043] When the first clamping mechanism 4 clamps and the second clamping mechanism 5 does not clamp, the first piezoelectric stack 31 is energized, and the first piezoelectric stack 31 elongates, thereby pushing the partition frame 21, the Y-direction moving platform, and the second clamping mechanism 5 to move one step to the right; when the first clamping mechanism 4 does not clamp and the second clamping mechanism 5 clamps, the first piezoelectric stack 31 is powered off, and the first piezoelectric stack 31 contracts, thereby pulling the two first clamping mechanisms 4 to move one step to the right through the first connecting block 22. By providing the flexible folding beam 32, the stability of the movement of the first clamping mechanism 4 can be improved, and the two sides of the partition frame 21 match the inner wall of the fixed platform 1.

[0044] The first clamping mechanism 4 includes a second piezoelectric stack 41 and a clamping block 44. First rigid blocks 42 are fixed at both ends of the second piezoelectric stack 41. The first rigid blocks 42 and the first connecting block 22 are flexibly connected through a first flexible plate 43. The first rigid blocks 42 and the clamping block 44 are flexibly connected through a second flexible plate 45. When the second piezoelectric stack 41 expands and contracts, it can drive the clamping block 44 to move away from or abut against the inner wall of the fixed platform 1. The ends of the first rigid block 42, the first flexible plate 43, the clamping block 44, and the first connecting block 22 form a bridge mechanism. When the second piezoelectric stack 41 is not energized, the side wall of the clamping block 44 abuts against the inner wall of the fixed platform 1 to realize the clamping of the fixed platform 1. When the second piezoelectric stack 41 is energized and elongates, the two first rigid blocks 42 in the same first clamping mechanism 4 move away from each other, and drive the second flexible plate 45 to move. The clamping block 44 is pulled by the second flexible plate 45 to move towards the second piezoelectric stack 41, so that the clamping block 44 is separated from the inner wall of the fixed platform 1, facilitating the movement of the first clamping mechanism 4.

[0045] The number of the second clamping mechanisms 5 is two. The two second clamping mechanisms 5 are connected through a second connecting block 24. The second connecting block 24 is a rigid member. The second clamping mechanism 5 includes a third piezoelectric stack 51 and a third connecting block 53. Second rigid blocks 52 are fixed at both ends of the third piezoelectric stack 51. Third flexible plates 54 are arranged on both sides of each second rigid block 52. The two ends of the third connecting block 53 and the two second rigid blocks 52 are connected through the third flexible plates 54. The side of the second rigid block 52 far away from the third connecting block 53 is also connected to the partition frame 21 through the third flexible plate 54. When the third piezoelectric stack 51 expands and contracts, the second rigid block 52 located on the outside can abut against or separate from the inner wall of the fixed platform 1;

[0046] As Figure 2As shown, in the initial state, there is a gap between the outer side of the second clamping mechanism 5 and the inner wall of the fixed platform 1. When the third piezoelectric stack 51 is energized, the third piezoelectric stack 51 elongates. By providing the third flexible plate 54, the third piezoelectric stack 51 can push the second rigid block 52 near the inner wall of the fixed platform 1 to move, so that the second rigid block 52 at this position abuts against the inner wall of the fixed platform 1, thereby realizing the clamping of the inner wall of the fixed platform 1.

[0047] As Figure 2 shown, in the initial state, the Y moving platform is placed in the installation groove 23. The length and width dimensions of the installation groove 23 are both larger than the length and width dimensions of the Y moving platform, that is, the Y moving platform is movably installed in the installation groove 23.

[0048] The third clamping mechanism 7 includes a fifth piezoelectric stack 71 and fifth connecting blocks 73 on both sides of the fifth piezoelectric stack 71. Fifth rigid blocks 72 are respectively fixed at both ends of the fifth piezoelectric stack 71. The two ends of the fifth connecting block 73 and the fifth rigid blocks 72 at both ends of the fifth piezoelectric stack 71 are flexibly connected by a sixth flexible plate 74. When the fifth piezoelectric stack 71 expands and contracts, the fifth rigid block 72 can movably abut against or disengage from the inner wall of the installation groove 23; when the fifth piezoelectric stack 71 is not energized, the fifth rigid blocks 72 at both ends of the fifth piezoelectric stack 71 do not contact the left and right inner walls of the installation groove 23. When the fifth piezoelectric stack 71 is energized, the fifth piezoelectric stack 71 elongates, thereby pushing the fifth rigid blocks 72 at both ends of the fifth piezoelectric stack 71 to move and abut against the left and right inner walls of the installation groove 23, thereby realizing the clamping of the installation groove 23.

[0049] As Figure 2 、 Figure 4 and Figure 5 shown, there is a gap between the second driving mechanism 6 and the inner wall of the partition frame 21. The second driving mechanism 6 includes an amplification mechanism and a fourth piezoelectric stack 61 inside the amplification mechanism. Both sides of the amplification mechanism are respectively connected to two third clamping mechanisms 7. The expansion and contraction of the fourth piezoelectric stack 61 can drive the amplification mechanism to move, so that the third clamping mechanism 7 moves in the Y direction. Specifically, the amplification mechanism includes third rigid blocks 62 fixed at both ends of the fourth piezoelectric stack 61 and amplification units on both sides of the fourth piezoelectric stack 61. Both ends of the amplification unit are respectively flexibly connected to the two third rigid blocks 62. The two amplification units are respectively connected to the two third clamping mechanisms 7;

[0050] When the upper third clamping mechanism 7 is not clamped with the inner wall of the installation groove 23 and the lower third clamping mechanism 7 is clamped with the inner wall of the installation groove 23, the fourth piezoelectric stack 61 is energized and elongated, which can push the two third rigid blocks 62 away from each other, thereby pulling the two amplification units closer to the fourth piezoelectric stack 61. The upper third clamping mechanism 7 is driven to move downward by one step through the amplification unit. And in this embodiment, even when the fourth piezoelectric stack 61 is elongated to the longest, the distance between the two third rigid blocks 62 is always less than the width of the installation groove 23. Therefore, when the lower third clamping mechanism 7 is clamped and the fourth piezoelectric stack 61 is energized and elongated, the second driving mechanism 6 can move downward synchronously with the upper third clamping mechanism 7, and the downward moving distance is the sum of the linear displacement distances of the two amplification units.

[0051] As Figure 5 shown, the amplification mechanism is an elliptical amplification mechanism. The amplification unit includes a fourth connecting block 66 and fourth rigid blocks 64 on both sides of the fourth connecting block 66. One side of the fifth connecting block 73 is connected to the fourth connecting block 66. The fourth connecting block 66 is flexibly connected to the fourth rigid blocks 64 on both sides through a fifth flexible plate 65. The two fourth rigid blocks 64 in the same amplification unit are respectively flexibly connected to the two third rigid blocks 62 through a fourth flexible plate 63;

[0052] When the fourth piezoelectric stack 61 is energized and elongated, the two third rigid blocks 62 move away from each other. In the same amplification unit, the fourth rigid block 64 is driven to move toward the fourth piezoelectric stack 61 through the fourth flexible plate 63. At the same time, when the fourth rigid block 64 moves, the fourth connecting block 66 is driven to move toward the fourth piezoelectric stack 61 through the fifth flexible plate 65. It can be seen that the displacement generated by the two amplification units is equivalent to four times the displacement. By setting the elliptical amplification mechanism, the displacement in the Y direction can be greatly increased, effectively improving the working stroke.

[0053] As Figure 7 and Figure 8 shown, through finite element analysis, when a displacement of 0.009 mm is applied to the two third rigid blocks 62, it can be seen from Figure 7 that the maximum generated displacement is 0.036945 mm, and the displacement amplification multiple is 4.105. And as Figure 8 shown, the maximum stress at this time is 95.097 Mpa, which is far lower than the allowable stress of the conventional displacement amplification mechanism, and the structural reliability is good.

[0054] As Figure 9As shown, it can be found that the elliptical magnifying mechanism has a high natural frequency, can respond more quickly to external excitation or signal changes, thereby improving the dynamic performance and response speed of the system, can return to a stable state more quickly when subjected to external disturbances, has good stability and strong anti-interference ability, and a high natural frequency means that the system can better track the target or maintain a stable state during the dynamic process, thereby enhancing the overall performance and accuracy of the system.

[0055] As Figure 6 shown, a driving method for a single-layer two-degree-of-freedom inchworm driver includes the following steps:

[0056] S1. (0 - t1 / t5 - t6): Energize the fifth piezoelectric stack 71 (lower third clamping mechanism 7) of a third clamping mechanism 7, the fifth piezoelectric stack 71 elongates when energized, the third clamping mechanism 7 clamps the partition frame 21, and at the same time, cut off the power supply to the second piezoelectric stack of the first clamping mechanism 4, and the first clamping mechanism 4 clamps with the fixed platform 1;

[0057] S2. (t1 - t2): Energize the first piezoelectric stack 31 of the first driving mechanism 3 and the fourth piezoelectric stack 61 of the second driving mechanism 6, the partition frame 21 and the second clamping mechanism 5 move one step in the X direction, and another third clamping mechanism 7 (upper third clamping mechanism 7) and the second driving mechanism 6 move one step in the Y direction to achieve movement in the X and Y directions;

[0058] S3. (t2 - t3): Energize the third piezoelectric stack 51 of the second clamping mechanism 5 and the fifth piezoelectric stack 71 of the third clamping mechanism 7 in step S2 to elongate, the second clamping mechanism 5 clamps the fixed platform 1, and the third clamping mechanism 7 clamps the partition frame 21;

[0059] S4. (t3 - t4): Cut off the power supply to the fifth piezoelectric stack 71 of the third clamping mechanism 7 in step S1, the third clamping mechanism 7 separates from the partition frame 21, and at the same time, energize the second piezoelectric stack 41 of the first clamping mechanism 4, and the first clamping mechanism 4 separates from the fixed platform 1;

[0060] S5. (t4 - t5): Cut off the power supply to the first piezoelectric stack 31 of the first driving mechanism 3 and the fourth piezoelectric stack 61 of the second driving mechanism 6, the first clamping mechanism 4 moves one step in the X direction, and the third clamping mechanism 7 in step S1 and the second driving mechanism 6 move one step in the Y direction to achieve movement in the X and Y directions again;

[0061] S6. Repeat steps S1 - S5.

[0062] Thus, through the above control timing, continuous output of displacements in the X and Y directions can be achieved.

[0063] The above are only the preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions falling within the concept of the present invention belong to the protection scope of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements should also be regarded as within the protection scope of the present invention.

Claims

1. A single-layer two-degree-of-freedom inchworm actuator, characterized in that, It includes a fixed platform (1). Inside the fixed platform (1), there is an X-direction moving platform and a Y-direction moving platform, and the X-direction moving platform and the Y-direction moving platform are in the same plane; The X-direction moving platform includes a frame (2). The frame (2) includes a partition frame (21). On both sides of the partition frame (21), there are respectively a first clamping mechanism (4) and a second clamping mechanism (5). The first clamping mechanism (4) and the second clamping mechanism (5) can respectively clamp with the fixed platform (1). The first clamping mechanism (4) is connected to the partition frame (21) through a first driving mechanism (3). An installation groove (23) is provided inside the partition frame (21), and the Y-direction moving platform is located inside the installation groove (23); The Y-direction moving platform includes a second driving mechanism (6). On both sides of the second driving mechanism (6), there are third clamping mechanisms (7) connected. The third clamping mechanisms (7) can clamp with the inner wall of the installation groove (23). The number of the first clamping mechanisms (4) is two. The two first clamping mechanisms (4) are connected through a first connecting block (22). The first connecting block (22) is connected to the partition frame (21) through a first driving mechanism (3). The first driving mechanism (3) includes a first piezoelectric stack (31). On both sides of the first piezoelectric stack (31), there are flexible folding beams (32). The two ends of the first piezoelectric stack (31) and the flexible folding beams (32) are respectively connected to the first connecting block (22) and the partition frame (21). When the first piezoelectric stack (31) expands and contracts, it can drive the first clamping mechanism (4) to move in the X direction. The first clamping mechanism (4) includes a second piezoelectric stack (41) and a clamping block (44). At both ends of the second piezoelectric stack (41), there are first rigid blocks (42) fixed. The first rigid blocks (42) are flexibly connected to the first connecting block (22) through a first flexible plate (43). The first rigid blocks (42) are flexibly connected to the clamping block (44) through a second flexible plate (45). When the second piezoelectric stack (41) expands and contracts, it can drive the clamping block (44) to move away from or abut against the inner wall of the fixed platform (1); The number of the second clamping mechanisms (5) is two. The two second clamping mechanisms (5) are connected through a second connecting block (24). The second clamping mechanism (5) includes a third piezoelectric stack (51) and a third connecting block (53). At both ends of the third piezoelectric stack (51), there are second rigid blocks (52) fixed. The two ends of the third connecting block (53) are connected to the two second rigid blocks (52) through a third flexible plate (54). The side of the second rigid block (52) far away from the third connecting block (53) is connected to the partition frame (21) through a third flexible plate (54). When the third piezoelectric stack (51) expands and contracts, the second rigid block (52) located on the outside can abut against or disengage from the inner wall of the fixed platform (1); The second driving mechanism (6) has a gap with the inner wall of the partition frame (21). The second driving mechanism (6) includes an amplification mechanism and a fourth piezoelectric stack (61) located inside the amplification mechanism. Both sides of the amplification mechanism are respectively connected to two third clamping mechanisms (7). The expansion and contraction of the fourth piezoelectric stack (61) can drive the amplification mechanism to move, so that the third clamping mechanism (7) moves along the Y direction; The amplification mechanism includes amplification units located on both sides of the fourth piezoelectric stack (61). The amplification unit includes a fourth connection block (66). The third clamping mechanism (7) includes a fifth piezoelectric stack (71) and fifth connection blocks (73) located on both sides of the fifth piezoelectric stack (71). Fifth rigid blocks (72) are respectively fixed at both ends of the fifth piezoelectric stack (71). Both ends of the fifth connection block (73) are flexibly connected to the fifth rigid blocks (72) at both ends of the fifth piezoelectric stack (71) through a sixth flexible plate (74). One side of the fifth connection block (73) is connected to the fourth connection block (66). When the fifth piezoelectric stack (71) expands and contracts, the fifth rigid block (72) can movably abut against or disengage from the inner wall of the installation groove (23).

2. The single-layer two-degree-of-freedom inchworm actuator according to claim 1, wherein, The amplification mechanism includes third rigid blocks (62) fixed at both ends of the fourth piezoelectric stack (61). Both ends of the amplification unit are respectively flexibly connected to the two third rigid blocks (62). The two amplification units are respectively connected to the two third clamping mechanisms (7).

3. The single-layer two-degree-of-freedom inchworm actuator according to claim 2, wherein The amplification mechanism is an elliptical amplification mechanism. The amplification unit includes fourth rigid blocks (64) located on both sides of the fourth connection block (66). The fourth connection block (66) is flexibly connected to the fourth rigid blocks (64) on both sides through a fifth flexible plate (65). The two fourth rigid blocks (64) in the same amplification unit are respectively flexibly connected to the two third rigid blocks (62) through a fourth flexible plate (63).

4. A driving method for a single-layer two-degree-of-freedom inchworm driver, which uses a single-layer two-degree-of-freedom inchworm driver as described in any one of claims 1-3, characterized in that, It includes the following steps: S1. Electrify the fifth piezoelectric stack (71) of a third clamping mechanism (7). The fifth piezoelectric stack (71) elongates when electrified, and this third clamping mechanism (7) clamps the partition frame (21). At the same time, cut off the power supply to the second piezoelectric stack of the first clamping mechanism (4), and the first clamping mechanism (4) clamps with the fixed platform (1); S2. Electrify the first piezoelectric stack (31) of the first driving mechanism (3) and the fourth piezoelectric stack (61) of the second driving mechanism (6). The partition frame (21) and the second clamping mechanism (5) move one step along the X direction, and the other third clamping mechanism (7) and the second driving mechanism (6) move one step along the Y direction to achieve the movement in the X direction and the Y direction; S3. Electrify the third piezoelectric stack (51) of the second clamping mechanism (5) and the fifth piezoelectric stack (71) of the third clamping mechanism (7) in step S2 to make them elongate. The second clamping mechanism (5) clamps the fixed platform (1), and this third clamping mechanism (7) clamps the partition frame (21); S4. Cut off the power supply to the fifth piezoelectric stack (71) of the third clamping mechanism (7) in step S1. The third clamping mechanism (7) is separated from the partition frame (21). At the same time, supply power to the second piezoelectric stack (41) of the first clamping mechanism (4), and the first clamping mechanism (4) is separated from the fixed platform (1). S5. Cut off the power supply to the first piezoelectric stack (31) of the first driving mechanism (3) and the fourth piezoelectric stack (61) of the second driving mechanism (6). The first clamping mechanism (4) moves one step in the X direction, and the third clamping mechanism (7) and the second driving mechanism (6) in step S1 move one step in the Y direction, realizing the movement in the X and Y directions again. S6. Repeat steps S1 - S5 to realize the continuous output of displacements in the X and Y directions.

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