Piezoelectric stick-slip driver

Abstract

The invention relates to a piezoelectric stick-slip driver comprising a shell unit which comprises a base and a cover body, and a storage space is formed when the cover body and the base are buckled; the stator unit is arranged on the base, the stator unit comprises a flexible hinge frame and a piezoelectric stacking assembly, the flexible hinge frame comprises a flexible element, the flexible element is arranged to be in a torsional spring-like form and can generate elastic deformation under the action of the piezoelectric stacking assembly, and the piezoelectric stacking assembly is connected with the flexible hinge frame; the input force is transmitted to the flexible hinge frame to drive the flexible hinge frame to elastically move; the mover unit comprises a fixed block and a sliding block, the fixed block is installed on the base in the first direction, and the sliding block is connected with the fixed block in a sliding mode. According to the piezoelectric stick-slip driver, the deformation recovery efficiency, the driving precision and the friction force regulation and control capability of the piezoelectric stick-slip driver can be improved, high-precision driving is achieved, meanwhile, good stability can be achieved, and the piezoelectric stick-slip driver is suitable for application scenes such as precision positioning and high-frequency vibration control.

Description

Technical Field

[0001] The invention relates to the field of micro-nano precision driving technology, in particular to a piezoelectric stick-slip driver. Background Art

[0002] In precision machinery and automated control systems, hinge structures are core components, and their performance directly determines the stability and accuracy of the system. With the advancement of miniaturization and integration, existing hinge structures are facing higher precision requirements and response speed requirements. Especially in the field of micro-nano manufacturing, in applications such as micro-electromechanical systems (MEMS) and microfluidic systems (μ-FS), hinge structures need to have higher flexibility and recovery capabilities. Specifically, microfluidic systems (μ-FS) are fluid processing systems based on micro-electromechanical system technology, which usually use micro-actuators such as microchannels, micropumps, and microvalves to accurately control and operate small volumes of fluid. The driving mechanism of piezoelectric stick-slip actuators relies on the combination of piezoelectric effect and stick-slip phenomenon, and mainly relies on the deformation of piezoelectric materials when an electric field is applied. This deformation can serve as the driving source of flexible hinges.

[0003] However, the defects of the prior art are that the traditional hinge structure usually recovers slowly after deformation and often lacks sufficient driving force to ensure precise control; in addition, although the existing piezoelectric stick-slip actuator can provide a certain deformation capability, it has obvious limitations in recovery speed and driving force output, and the speed of deformation recovery and the size of the driving force cannot be well coordinated, thereby affecting the overall driving efficiency. Summary of the invention

[0004] To this end, the technical problem to be solved by the present invention is to overcome the deficiencies in the prior art and provide a piezoelectric stick-slip actuator that can increase the driving speed of the flexible hinge during the sliding stage, reduce friction, reduce the retraction displacement of the slider, and improve the overall driving efficiency.

[0005] In order to solve the above technical problems, the present invention provides a piezoelectric stick-slip actuator, comprising: A housing unit, comprising a base and a cover, wherein the cover forms a storage space when the base is buckled together; A stator unit is arranged on the base, the stator unit comprises a flexible hinge frame and a piezoelectric stack assembly, the flexible hinge frame comprises a flexible element, the flexible element is arranged in a torsion spring-like form, and can generate elastic deformation under the action of the piezoelectric stack assembly, the piezoelectric stack assembly is connected to the flexible hinge frame to transmit input force to the flexible hinge frame and drive the flexible hinge frame to perform elastic movement; The movable subunit comprises a fixed block and a sliding block, wherein the fixed block is mounted on the base along a first direction, the sliding block is slidably connected to the fixed block, and the sliding block can move along the first direction, and the sliding block moves under the drive of the flexible hinge frame.

[0006] In one embodiment of the present invention, the piezoelectric stack assembly includes a first stack block, a second stack block and a pre-tightening connection block, and the first stack block and the second stack block are connected in series through the pre-tightening connection block.

[0007] In one embodiment of the present invention, one end of the base extends along the height direction to form a first connecting plate, and the flexible hinge frame is installed on the first connecting plate; the base has a first mounting surface and a second mounting surface in sequence along the second direction, the stator unit is arranged on the first mounting surface, and the mover unit is arranged on the second mounting surface, the height of the second mounting surface is higher than the first mounting surface, and the second direction is perpendicular to the first direction.

[0008] In one embodiment of the present invention, the flexible hinge frame includes a stator connection block, a flexible support arm, a flexible cross beam arm and a stick-slip head, wherein the stator connection block is mounted on the base by fasteners, two flexible support arms are provided, one end of the two flexible support arms is connected to the stator connection block, and the other end of the two flexible support arms is connected to the flexible cross beam arm, the stator connection block, the flexible support arm and the flexible cross beam arm are surrounded to form a receiving space, the flexible element is connected to the flexible support arm and is located in the receiving space; the flexible cross beam arm is arranged in a "V-shape", the stick-slip head is arranged on the flexible cross beam arm, and is located on a side of the flexible cross beam arm close to the mover unit, and the stick-slip head is driven to move along the second direction.

[0009] In one embodiment of the present invention, the flexible hinge frame also includes a first mounting groove and a second mounting groove, and the first mounting groove and the second mounting groove are symmetrically arranged on the two flexible support arms respectively, and the two ends of the piezoelectric stack assembly along the first direction are respectively embedded in the first mounting groove and the second mounting groove to provide driving force to the flexible support arm.

[0010] In one embodiment of the present invention, the flexible element includes a body and a connecting portion, the body is arranged in an "S-shape", two connecting portions are symmetrically arranged, and both ends of the body are connected to the flexible support arm through the connecting portions respectively.

[0011] In one embodiment of the present invention, the body includes a first curved portion and a second curved portion located at both ends, and a third curved portion located in the middle, and the curvature radius of the first curved portion and the second curved portion is defined as , the curvature radius of the third curved portion is defined as , The range is 0.5-0.8.

[0012] In one embodiment of the present invention, the body is a structure of equal thickness, and the wall thickness of the body is 0.02-0.05 times the extension length of the body.

[0013] In one embodiment of the present invention, the mover unit further includes a retaining frame and a rolling assembly, wherein the retaining frame is arranged between the fixed block and the sliding block, and the rolling assembly is movably arranged on the retaining frame, and the rolling assembly is in rolling contact with the fixed block and the sliding block; the rolling assembly includes a plurality of rollers, and a plurality of the roller arrays are arranged on the retaining frame.

[0014] In one embodiment of the present invention, the base is slidably connected to the cover body, wherein a slide groove assembly is provided on a side of the base, and a slider assembly matching the slide groove assembly is provided on an edge of the cover body.

[0015] The above technical solution of the present invention has the following advantages compared with the prior art: A piezoelectric stick-slip actuator described in the present invention is provided with a housing unit, a stator unit and a mover unit, wherein the stator unit and the mover unit are accommodated in the housing unit, and the stator unit includes a flexible hinge frame and a piezoelectric stack assembly, wherein the flexible hinge frame includes a flexible element configured as a torsion spring-like structure, so that the flexible hinge frame can generate rapid elastic deformation and recover rapidly under the deformation of the piezoelectric stack assembly, thereby ensuring efficient and accurate force transmission, and through the compression deformation generated by the piezoelectric stack assembly, combined with the torsion deformation of the flexible hinge frame, compression-torsion coupling is realized to drive the sliding block of the mover unit to move. The piezoelectric stick-slip actuator of the present invention adopts a flexible element designed in a torsion spring-like shape, and cooperates with a sawtooth wave voltage signal as a driving signal source, so that the friction between the stick-slip head and the sliding block can be dynamically adjusted. During the period when the signal source slowly rises, the friction between the stick-slip head and the sliding block is large, and during the period when the signal source quickly drops, the flexible element quickly retracts the stick-slip head, thereby reducing the friction and realizing efficient movement of the sliding block. As a result, the deformation recovery efficiency, driving accuracy and friction force control ability of the piezoelectric stick-slip actuator can be improved, so that it can achieve high-precision driving while also having good stability, making it suitable for application scenarios such as precision positioning and high-frequency vibration control.

[0016] The present invention optimizes the structural design of the flexible hinge frame, so that it can recover to its initial state more quickly and accurately after being acted upon by external forces, thereby improving the overall dynamic response performance of the system. During the piezoelectric stick-slip drive process, due to the high recovery efficiency of the hinge, the backlash phenomenon of the sliding block during the working cycle is significantly reduced, thereby improving the unidirectional movement efficiency and displacement accuracy of the sliding block. Compared with the current existing technology, the output speed is increased by more than 15%, the output efficiency is increased by more than 15%, the displacement backlash rate is reduced by more than 18%, and the positioning accuracy under open-loop conditions can reach nanometer level. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0018] Figure 1 It is a schematic diagram of the overall structure of a piezoelectric stick-slip actuator according to a preferred embodiment of the present invention.

[0019] Figure 2 It is a schematic structural diagram of a stator unit according to a preferred embodiment of the present invention without a piezoelectric stack assembly.

[0020] Figure 3 It is a schematic structural diagram of a stator unit according to a preferred embodiment of the present invention.

[0021] Figure 4 It is a schematic structural diagram of a mover unit according to a preferred embodiment of the present invention.

[0022] Figure 5 It is a schematic structural diagram of a base according to a preferred embodiment of the present invention.

[0023] Figure 6 It is a schematic structural diagram of a cover body according to a preferred embodiment of the present invention.

[0024] Figure 7 It is a schematic diagram of an enlarged structure of a flexible element according to a preferred embodiment of the present invention.

[0025] Figure 8 It is a schematic diagram of the initial state of the driving method of the piezoelectric stick-slip actuator according to the preferred embodiment of the present invention.

[0026] Fig. 9 yes Figure 8 Schematic diagram of the electrical signal waveform.

[0027] Fig.10 It is a schematic diagram of the slow rising stage of the driving method of the piezoelectric stick-slip actuator according to the preferred embodiment of the present invention.

[0028] Fig.11 yes Fig.10 Schematic diagram of the electrical signal waveform.

[0029] Fig.12 It is a schematic diagram of the switching points between the "sticky" and "slip" states of the driving method of the piezoelectric stick-slip actuator according to the preferred embodiment of the present invention.

[0030] Fig.13 yes Fig.12 Schematic diagram of the electrical signal waveform.

[0031] Fig.14 It is a schematic diagram of the rapid descending stage of the driving method of the piezoelectric stick-slip actuator according to the preferred embodiment of the present invention.

[0032] Fig.15 yes Fig.14 Schematic diagram of the electrical signal waveform.

[0033] Description of the reference numerals in the specification: 1. housing unit; 10. base; 101. first connecting plate; 1011. first pre-tightening bolt; 1012. second pre-tightening bolt; 102. first mounting surface; 103. second mounting surface; 1030. first mounting hole; 105. side slide groove; 11. cover; 110. first slider; 111. second slider; 2. stator unit; 20. flexible hinge frame; 201. sticky slide head; 202 , stator connecting block; 2020, second mounting hole; 203, flexible support arm; 204, flexible beam arm; 205, first mounting slot; 206, second mounting slot; 207, main body; 208, connecting part; 21, piezoelectric stacking assembly; 211, first stacking block; 212, second stacking block; 213, pre-tightening connecting block; 3, mover unit; 30, fixed block; 31, sliding block; 310, limit bolt; 32, retaining frame. DETAILED DESCRIPTION

[0034] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0035] The piezoelectric effect refers to the phenomenon that when certain dielectrics are deformed by external forces in a certain direction, polarization will occur inside them, and opposite positive and negative charges will appear on their two opposite surfaces. When the external force is removed, it will return to an uncharged state. This phenomenon is called the positive piezoelectric effect. When the direction of the force changes, the polarity of the charge also changes. Conversely, when an electric field is applied in the polarization direction of the dielectric, these dielectrics will also deform. When the electric field is removed, the deformation of the dielectric disappears. This phenomenon is called the inverse piezoelectric effect.

[0036] The piezoelectric stick-slip actuator made by the piezoelectric effect produces alternating motion during the stick-slip process, which mainly includes two stages: adhesion and sliding. During stick-slip, the driving speed is slow and the friction between the slider and the contact surface is large, thus driving the slider to move. During sliding, the driving speed is fast and the slider breaks through the restraint of static friction and slides quickly. It can be seen from the stick-slip process that if the efficiency of slider displacement is to be improved, the recovery speed after hinge deformation is required to be high. Embodiment 1

[0037] Reference Figures 1 to 7 As shown, the present invention discloses a piezoelectric stick-slip actuator, comprising a housing unit 1, wherein the housing unit 1 comprises a base 10 and a cover 11, and the cover 11 can form a storage space when the base 12 is buckled.

[0038] The piezoelectric stick-slip actuator further includes a stator unit 2, which is disposed on the base 10. The stator unit includes a flexible hinge frame 20 and a piezoelectric stack assembly 21, and the piezoelectric stack assembly 21 is connected to the flexible hinge frame 20 to transmit input force to the flexible hinge frame 20, thereby driving the flexible hinge frame 20 to perform elastic movement.

[0039] Specifically, the flexible hinge frame 20 includes a flexible element and a sticky head 201, wherein the flexible element is configured to be in a torsion spring-like form so as to be able to generate elastic deformation under the action of the piezoelectric stack assembly 21. The sticky head 201 is connected to the flexible element and can move under the drive of the flexible element.

[0040] The piezoelectric stick-slip actuator further includes a mover unit 3, which includes a fixed block 30 and a sliding block 31. The fixed block 30 is mounted on the base 10 along a first direction, and the sliding block 31 is slidably connected to the fixed block 30, and the sliding block 31 can move along the first direction. It should be noted that the sliding block 31 can move precisely under the drive of the flexible hinge frame 20. In detail, when working, the sliding block 31 contacts the stick-slip head 201 of the flexible hinge frame 20.

[0041] It can be known that the piezoelectric stick-slip actuator to be protected by the present invention is provided with a housing unit, a stator unit and a mover unit, the stator unit and the mover unit are accommodated in the housing unit, the stator unit includes a flexible hinge frame and a piezoelectric stack assembly, wherein the flexible hinge frame includes a flexible element configured as a torsion spring-like structure, so that the flexible hinge frame can produce rapid elastic deformation and recover rapidly under the deformation of the piezoelectric stack assembly, ensuring efficient and accurate force transmission, and through the compression deformation generated by the piezoelectric stack assembly, combined with the torsion deformation of the flexible hinge frame, compression-torsion coupling is realized to drive the sliding block of the mover unit to move. The piezoelectric stick-slip actuator of the present invention adopts a flexible element designed in a torsion spring-like shape, and cooperates with a sawtooth voltage signal as a driving signal source, so that the friction between the stick-slip head and the sliding block can be dynamically adjusted. During the period when the signal source slowly rises, the friction between the stick-slip head and the sliding block is large, and during the period when the signal source quickly drops, the flexible element quickly retracts the stick-slip head, thereby reducing the friction and realizing efficient movement of the sliding block. As a result, the deformation recovery efficiency, driving accuracy and friction force control ability of the piezoelectric stick-slip actuator can be improved, so that it can achieve high-precision driving while also having good stability, making it suitable for application scenarios such as precision positioning and high-frequency vibration control.

[0042] As a preferred embodiment, the base 10 adopts a right-angle frame structure. Preferably, the base 10 is made of a rigid material to enhance its bearing capacity and stability.

[0043] As a preferred embodiment, the stator unit includes a flexible hinge frame 20 and a piezoelectric stack assembly 21, and the piezoelectric stack assembly 21 includes a first stack block 211, a second stack block 212 and a pre-tightening connection block 213, wherein the first stack block 211 and the second stack block 212 are spaced apart along the first direction, and the first stack block 211 and the second stack block 212 are connected in series via the pre-tightening connection block 213. In detail, the shape of the pre-tightening connection block 213 is set to be a wedge. With such a setting, the pre-tightening connection block 213 connects the first stack block 211 and the second stack block 212 in series to generate a driving force, and is connected to the flexible hinge frame 20 to transmit the linear input force to the entire system, and realizes a torsion spring-like elastic movement through the overall deformation of the flexible hinge frame 20, so as to push the sliding block 31 to move precisely.

[0044] Further, one end of the base 10 is extended along the height direction to form a first connecting plate 101, and the flexible hinge frame 20 is installed on the first connecting plate 101. The base 10 has a first mounting surface 102 and a second mounting surface 103 in sequence along the second direction, the stator unit 2 is arranged on the first mounting surface 102, the mover unit 3 is arranged on the second mounting surface 103, the height of the second mounting surface 103 is higher than the first mounting surface 102, and the second direction is perpendicular to the first direction.

[0045] Such a configuration can provide sufficient movement space for the stick-slip process of the stator unit 2 and the stick-sliding block 201. In addition, a first mounting hole 1030 is provided on the second mounting surface 103, so that the fixing block 30 can be fixedly assembled on the second mounting surface 103, thereby ensuring that the movement of the sliding block 31 is stable and smooth, and effectively improving the movement accuracy.

[0046] As a preferred embodiment, the flexible hinge frame 20 includes a stator connection block 202, a flexible support arm 203, and a flexible crossbeam arm 204. The stator connection block 202 is mounted on the base 10 by fasteners. In detail, a second mounting hole 2020 is opened on the stator connection block 202 along the second direction, and the stator connection block 202 is mounted on the first connecting plate 101 by fasteners.

[0047] The second mounting hole 2020 is tightly engaged with the first pre-tightening bolt 1011 assembled on the first connecting plate 101 and cooperates with the second pre-tightening bolt 1012 to fix the flexible hinge frame 20 at a preset position in the second direction.

[0048] The flexible support arms 203 are provided with two, one end of the two flexible support arms 203 is connected to the stator connection block 202, and the other end of the two flexible support arms 203 is connected to the flexible cross beam arm 204, the stator connection block 202, the flexible support arms 203 and the flexible cross beam arm 204 are surrounded to form a receiving space, and the flexible element is connected to the flexible support arms 203 and is located in the receiving space.

[0049] Specifically, the flexible cross beam arm 204 is arranged in a "V-shape", the stick-slip head 201 is arranged on the flexible cross beam arm 204 and is located on a side of the flexible cross beam arm 204 close to the mover unit 3, and the stick-slip head 201 can be driven to move along the second direction.

[0050] The flexible hinge frame 20 further includes a first mounting groove 205 and a second mounting groove 206, wherein the first mounting groove 205 and the second mounting groove 206 are symmetrically arranged on the two flexible support arms 203, and the first mounting groove 205 and the second mounting groove 206 are arranged opposite to each other. The two ends of the piezoelectric stack assembly 21 along the first direction are respectively embedded in the first mounting groove 205 and the second mounting groove 206 to provide driving force to the flexible support arm 203.

[0051] Specifically, the first stacking block 211 is embedded in the first mounting groove 205, and the second stacking block 212 is embedded in the second mounting groove 206. The first stacking block 211 and the second stacking block 212 are respectively tightly pressed into the first mounting groove 205 and the second mounting groove 206 by the pre-tightening connection block 213, thereby improving the response speed and stability of the stator unit 2.

[0052] The flexible element includes a body 207 and a connecting portion 208 . The body 207 is arranged in an “S-shape”. Two connecting portions 208 are symmetrically arranged. Both ends of the body 207 are connected to the flexible support arm 203 through the connecting portions 208 .

[0053] During operation, the piezoelectric stack assembly 21 is connected to the flexible support arm 203 through the first mounting groove 205 and the second mounting groove 206 to provide a driving force in the first direction to the flexible support arm 203, thereby driving the flexible support arm 203 to deform. The flexible support arm 203 is connected to the "V-shaped" flexible beam arm 204 through a groove, thereby driving the "V-shaped" flexible beam arm 204 to bend and deform toward a "straight line". The flexible beam arm 204 can optimize the conversion between stress and deformation, so that the motion energy can be efficiently transmitted. The stick-slip head 201 is located on a single-side arm of the "V-shaped" flexible beam, so that the bending energy of the "V-shaped" flexible beam arm 204 can be transmitted to the stick-slip head 201, causing the stick-slip head 201 to generate displacement along the second direction. The "S-shaped" flexible element is a key part of the structure of the stator unit 2. It stores and releases energy through elastic deformation. When the flexible support arms 203 on both sides are deformed outward, they can provide elastic restoring force, thereby quickly restoring the flexible support arms 203 to their initial state, thereby driving the sticky head 201 to retreat quickly.

[0054] The flexible element is composed of a plurality of curved parts, each of which provides elastic energy storage capability. In detail, the body 207 includes a first curved part 2071 and a second curved part 2072 at both ends, and a third curved part 2073 at the middle. The curvature radius of the first curved part 2071 and the second curved part 2072 is defined as , the curvature radius of the third curved portion 2073 is defined as , The range is 0.5-0.8. In this way, the axial stiffness and deformation of the structure can be controlled by designing the curvature difference. Smaller, used to increase the sensitivity of initial deformation, The larger the radius of curvature, the higher the rigidity and deformation energy storage capacity. The combination of different curvature radii can optimize the axial and lateral rigidity distribution, thereby ensuring uniform deformation distribution, reducing local stress concentration, and extending the fatigue life of the flexible element.

[0055] It should be noted that the flexible element is an "S-shaped" structure that is symmetrical up and down, which effectively ensures that the stress distribution is uniform during the deformation process, and no tilting or twisting occurs, thereby improving the deformation efficiency and mechanical stability. When applied to the piezoelectric stick-slip device, it can significantly increase the retraction speed of the stator unit 2, effectively shorten the motion cycle, and at the same time ensure the high reliability and low energy consumption of the entire system.

[0056] As a preferred embodiment, the body 207 is a structure of constant thickness. Specifically, the wall thickness of the body 207 is 0.02-0.05 times the extension length of the horizontal cross section of the body 207.

[0057] Specifically, the mover unit 3 further includes a retaining frame 32 and a rolling assembly, wherein the retaining frame 32 is mounted on the base 10 and is located between the fixed block 30 and the sliding block 31. The rolling assembly is movably arranged on the retaining frame 32 and is stably arranged by the retaining frame 32, providing smooth and low-friction support for the sliding of the sliding block 31. The rolling assembly is in rolling contact with the fixed block 31 and the sliding block.

[0058] As a preferred embodiment, the rolling assembly includes a plurality of rollers, and the plurality of roller arrays are arranged in the retaining frame 32 .

[0059] In order to limit the movement of the sliding block 31 and prevent the travel of the sliding block 31 from exceeding the range of the retaining frame 32, a limiting bolt 310 is also provided on the sliding block 31. The limiting bolt 31 is arranged at both ends of the sliding block 31. A positioning bar is also provided inside the sliding block 31. The limiting bolt 31 cooperates with the positioning bar to achieve limitation.

[0060] As a preferred embodiment, in order to reduce sliding resistance and increase wear resistance, the side of the sliding block 31 opposite to the fixed block 30 is coated with a friction ceramic layer; correspondingly, the side of the fixed block 30 opposite to the sliding block 30 is also coated with a friction ceramic layer.

[0061] As a preferred embodiment, the base 10 is slidably connected to the cover body 11, wherein a slide groove assembly is provided on the side of the base 10, and a slider assembly matching the slide groove assembly is provided on the edge of the cover body 11.

[0062] In detail, the side of the base 10 is provided with a side slide groove 105, and the cover 11 is provided with a first slider 110 to match the side slide groove 105. After being inserted, it can realize the movable connection in the front and rear directions, and lock the cover 11 and the base 10 in the height direction. The top of the first connecting plate 101 is provided with a top slide groove 106, and the cover 11 is provided with a second slider 111 to match the top slide groove 106. In this way, the base 10 and the cover 11 can be closed and also easy to disassemble. Embodiment 2

[0063] The present invention also discloses a driving method, combining Figures 8 to 15 As shown, driving is performed using the piezoelectric stick-slip actuator described in the first embodiment.

[0064] Specifically, the driving method uses a sawtooth voltage signal as an input voltage waveform; A sawtooth wave electrical signal is applied to both ends of the piezoelectric stacking assembly 21 in the form of a parallel voltage. The first stacking block 211 and the second stacking block 212 in the piezoelectric stacking assembly are connected in series and deformed in a first direction, pushing the flexible support arm 203 to move. Based on the "sticky" effect, the sliding block 31 will move along the extension direction (first direction) of the fixed block 30. In the rapid deformation stage, thanks to the design of the flexible element with a torsion spring-like structure, the rapid deformation efficiency is higher, and it is easier for the sliding block 31 to break through the static friction and suppress the retreat movement.

[0065] Among them, the sawtooth driving wave period is T1, the excitation voltage amplitude is V1, the symmetry is D, the sawtooth driving wave period T1 ranges from 0.001 to 1s, the excitation voltage amplitude V1 ranges from 60 to 120V, and the symmetry can be 50 to 99.99%.

[0066] It can be seen that the present invention optimizes the structural design of the flexible hinge frame, so that it can recover to its initial state more quickly and accurately after being subjected to external force, thereby improving the overall dynamic response performance of the system. During the piezoelectric stick-slip drive process, due to the high recovery efficiency of the hinge, the retreat phenomenon of the sliding block during the working cycle is significantly reduced, thereby improving the unidirectional movement efficiency and displacement accuracy of the sliding block. Compared with the current existing technology, the output speed is increased by more than 15%, the output efficiency is increased by more than 15%, the displacement retreat rate is reduced by more than 18%, and the positioning accuracy under open-loop conditions can reach nanometers.

[0067] Of course, in subsequent designs, further improvements can be made based on this type of torsion spring flexible hinge frame structure, such as using asymmetric "S"-shaped elements, improving control signals, and combining different control methods to achieve bidirectional displacement of the slider, because the "S"-shaped element can provide sufficient torque to drive the slider to displace.

[0068] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0069] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0070] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A piezoelectric stick-slip actuator, characterized in that: include, A housing unit, comprising a base and a cover, wherein the cover forms a storage space when the base is buckled together; A stator unit is arranged on the base, the stator unit comprises a flexible hinge frame and a piezoelectric stack assembly, the flexible hinge frame comprises a flexible element, the flexible element is arranged in a torsion spring-like form, and can generate elastic deformation under the action of the piezoelectric stack assembly, the piezoelectric stack assembly is connected to the flexible hinge frame to transmit input force to the flexible hinge frame and drive the flexible hinge frame to perform elastic movement; The movable subunit comprises a fixed block and a sliding block, wherein the fixed block is mounted on the base along a first direction, the sliding block is slidably connected to the fixed block, and the sliding block can move along the first direction, and the sliding block moves under the drive of the flexible hinge frame.

2. A piezoelectric stick-slip actuator according to claim 1, characterized in that: The piezoelectric stack assembly includes a first stack block, a second stack block and a pre-tightening connection block, and the first stack block and the second stack block are connected in series through the pre-tightening connection block.

3. A piezoelectric stick-slip actuator according to claim 1, characterized in that: One end of the base extends along the height direction to form a first connecting plate, and the flexible hinge frame is installed on the first connecting plate; the base has a first mounting surface and a second mounting surface in sequence along the second direction, the stator unit is arranged on the first mounting surface, and the mover unit is arranged on the second mounting surface, the height of the second mounting surface is higher than the first mounting surface, and the second direction is perpendicular to the first direction.

4. A piezoelectric stick-slip actuator according to claim 3, characterized in that: The flexible hinge frame includes a stator connection block, a flexible support arm, a flexible cross beam arm and a sticky head, wherein the stator connection block is installed on the base by a fastener, two flexible support arms are provided, one end of the two flexible support arms is connected to the stator connection block, and the other end of the two flexible support arms is connected to the flexible cross beam arm, the stator connection block, the flexible support arm and the flexible cross beam arm are surrounded to form a receiving space, the flexible element is connected to the flexible support arm and is located in the receiving space; the flexible cross beam arm is arranged in a "V-shape", the sticky head is arranged on the flexible cross beam arm, and is located on a side of the flexible cross beam arm close to the mover unit, and the sticky head is driven to move along the second direction.

5. A piezoelectric stick-slip actuator according to claim 4, characterized in that: The flexible hinge frame also includes a first mounting groove and a second mounting groove, and the first mounting groove and the second mounting groove are symmetrically arranged on the two flexible support arms respectively. The two ends of the piezoelectric stack assembly along the first direction are respectively embedded in the first mounting groove and the second mounting groove to provide driving force to the flexible support arm.

6. A piezoelectric stick-slip actuator according to claim 4, characterized in that: The flexible element includes a main body and a connecting portion, the main body is arranged in an "S-shape", two connecting portions are symmetrically arranged, and both ends of the main body are connected to the flexible support arm through the connecting portions respectively.

7. A piezoelectric stick-slip actuator according to claim 6, characterized in that: The body includes a first curved portion and a second curved portion at two ends, and a third curved portion at the middle, and the curvature radius of the first curved portion and the second curved portion is defined as , the curvature radius of the third curved portion is defined as , The range is 0.5-0.

8.

8. The piezoelectric stick-slip actuator according to claim 6, characterized in that: The body is a structure of equal thickness, and the wall thickness of the body is 0.02-0.05 times the extension length of the body.

9. The piezoelectric stick-slip actuator according to claim 1, characterized in that: The mover unit also includes a retaining frame and a rolling assembly, wherein the retaining frame is arranged between the fixed block and the sliding block, and the rolling assembly is movably arranged on the retaining frame, and the rolling assembly is in rolling contact with the fixed block and the sliding block; the rolling assembly includes a plurality of rollers, and a plurality of the roller arrays are arranged on the retaining frame.

10. A piezoelectric stick-slip actuator according to any one of claims 1 to 9, characterized in that: The base is slidably connected to the cover body, wherein a slide groove assembly is arranged on a side of the base, and a slider assembly matching the slide groove assembly is arranged on an edge of the cover body.

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