Inchworm type piezoelectric motor and driving method thereof

Abstract

The invention relates to the field of motors, and provides an inchworm type piezoelectric motor which comprises a rotor and a plurality of clamping modules. Each clamping module comprises a flexible clamping hinge, a guide frame and piezoelectric ceramics. When the piezoelectric ceramic is electrified to deform and displace, the lower slope part of the flexible clamping hinge is driven to be attached to the upper slope part of the guide frame in the slope space, so that the upper slope part applies force pressing the axis of the rotor to the flexible clamping hinge by extruding the lower slope part to clamp the rotor, and the rotor moves through accumulation of deformation of the piezoelectric ceramic. The invention further relates to a driving method of the inchworm type piezoelectric motor. The invention aims to provide a long-stroke, high-thrust, high-resolution and high-positioning-precision motion mechanism driven by piezoelectric ceramics, and a high-precision linear motion solution can be provided for the industries of semiconductors, aerospace, medical equipment and the like.

Description

Technical Field

[0001] The present invention relates to the field of piezoelectric motors, and in particular to an inchworm-type piezoelectric motor and a driving method thereof. Background Art

[0002] In traditional inchworm-type piezoelectric motors, the driving mechanism is a combination of axially deformed ceramic sheets, tangentially deformed ceramic sheets, and flexible hinges or elastic elements. This driving mechanism provides limited clamping force on the mover, and the piezoelectric ceramic sheets will be subjected to shear force, so the thrust that the motor can provide is limited. Currently, mainstream products can only provide a maximum thrust of tens of Newtons. Summary of the invention

[0003] The object of the present invention is to provide a inchworm-type piezoelectric motor, which includes a mover and a plurality of clamping modules. Each clamping module includes a flexible clamping hinge, a guide frame and a piezoelectric ceramic. The flexible clamping hinge has a lower slope portion extending in a direction away from the center of the flexible clamping hinge, and the guide frame has an upper slope portion extending in a direction away from the center of the guide frame. When the piezoelectric ceramic is energized and deformed, the lower slope portion of the flexible clamping hinge is driven to fit with the upper slope portion of the guide frame in the slope space, so that the upper slope portion applies a force pressing toward the axis of the mover to the flexible clamping hinge by squeezing the lower slope portion, thereby clamping the mover, and the mover is moved by the accumulation of the deformation of the piezoelectric ceramic.

[0004] In order to solve the above problems, the present invention provides the following technical solutions.

[0005] In a first aspect, the present application provides an inchworm-type piezoelectric motor, comprising:

[0006] mover;

[0007] Multiple clamp modules, each clamp module includes:

[0008] A flexible clamping hinge, the flexible clamping hinge contacts the mover to clamp the mover; the left and right ends of the flexible clamping hinge along the axial direction of the mover are respectively provided with lower slope portions extending in a direction away from the center of the flexible clamping hinge; the flexible clamping hinge is provided with at least two first accommodating spaces;

[0009] A guide frame, wherein a second accommodating space is arranged on the guide frame, the flexible clamping hinge is sleeved in the second accommodating space, and the flexible clamping hinge is connected to the guide frame; an upper slope portion extending in a direction away from the center of the guide frame is arranged at the left and right ends of the guide frame along the axial direction of the mover, so that the left and right ends of the first accommodating space along the axial direction of the mover are respectively extended to form slope spaces at the left and right ends at the lower part of the upper slope portion;

[0010] At least two piezoelectric ceramics are sleeved in the first accommodating space. When the piezoelectric ceramics are energized and deformed, the lower slope portion of the flexible clamping hinge is driven to fit with the upper slope portion in the slope space, so that the upper slope portion applies a force to the flexible clamping hinge toward the axis of the mover by squeezing the lower slope portion, thereby clamping the mover and moving the mover through the accumulation of the piezoelectric ceramic deformation.

[0011] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, the mover is a segmented mover or a ring-shaped mover.

[0012] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, the lower slope portion is arranged at two free ends of the C-shaped cross section.

[0013] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, the inchworm-type piezoelectric motor includes: 4 clamping modules, each two clamping modules form a group, and the clamping modules in a group are arranged relatively to each other along the radial direction of the mover; a first accommodating space is respectively provided at the left and right ends of the flexible clamping hinge of each clamping module, and a left piezoelectric ceramic is sleeved in the first accommodating space at the left end of each clamping module, and a right piezoelectric ceramic is sleeved in the first accommodating space at the right end of each clamping module.

[0014] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, when the left piezoelectric ceramic of the first group of clamping modules is applied with a first voltage signal and the left piezoelectric ceramic of the second group of clamping modules remains in a non-powered state, the flexible clamping hinge of the first group of clamping modules clamps the mover and holds the mover to move to the left;

[0015] The left piezoelectric ceramic of the first clamping module is discharged, and at the same time, the left piezoelectric ceramic of the second clamping module is applied with a second voltage signal, and the flexible clamping hinge of the second clamping module clamps the mover and holds the mover to continue to move to the left; or,

[0016] When the first voltage signal is applied to the right piezoelectric ceramic of the clamping module of the first group and the right piezoelectric ceramic of the clamping module of the second group remains in a non-powered state, the flexible clamping hinge of the clamping module of the first group clamps the mover and holds the mover to move rightward;

[0017] The right piezoelectric ceramic of the first clamping module is discharged, and at the same time, the second voltage signal is applied to the right piezoelectric ceramic of the second clamping module. The flexible clamping hinge of the second clamping module clamps the mover and holds the mover to continue to move to the right.

[0018] Further, in the above-mentioned inchworm-type piezoelectric motor, a leading voltage signal is applied to the left piezoelectric ceramic of the same group of clamping modules, and a lagging voltage signal is applied to the right piezoelectric ceramic of the same group of clamping modules, and there is a phase difference between the leading voltage signal and the lagging voltage signal, and the flexible clamping hinge of the same group of clamping modules clamps the mover and holds the mover to move to the left; or,

[0019] A leading voltage signal is applied to the right piezoelectric ceramic of the clamping module of the same group, and a lagging voltage signal is applied to the left piezoelectric ceramic of the clamping module of the same group, and there is a phase difference between the leading voltage signal and the lagging voltage signal. The flexible clamping hinge of the clamping module of the same group clamps the mover and holds the mover to move to the right.

[0020] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, when voltage signals of different power supply voltages are applied to the left piezoelectric ceramics of the same group of clamping modules, the flexible clamping hinges of the group of clamping modules clamp the mover and hold the mover to move to the left at the nm level;

[0021] When voltage signals of different power supply voltages are applied to the right piezoelectric ceramics of the same group of clamping modules, the flexible clamping hinges of the group of clamping modules clamp the mover and hold the mover to move rightward at the nm level.

[0022] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, the positive electrode of the left piezoelectric ceramic of each clamping module is applied with the highest working voltage of the piezoelectric ceramic, the negative electrode of the right piezoelectric ceramic of each clamping module is grounded, the negative electrode of the left piezoelectric ceramic and the positive electrode of the right piezoelectric ceramic of each clamping module are connected in series through a connecting line, and a voltage signal is applied to the connecting line.

[0023] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, the two groups of clamping modules are arranged perpendicularly or parallel to each other.

[0024] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, a deformation groove is provided in a partial area on the flexible clamping hinge.

[0025] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, the size of the first accommodating space is larger than the outer contour size of the piezoelectric ceramic, so as to reserve space for deformation and elongation of the piezoelectric ceramic; the size of the second accommodating space is larger than the outer contour size of the flexible clamping hinge, so as to reserve space for deformation and elongation of the flexible clamping hinge.

[0026] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, a wear-resistant material is provided on the contact surface of the flexible clamping hinge that clamps the mover.

[0027] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, the wear-resistant material includes: any one of a zirconium oxide wear-resistant ceramic sheet, an aluminum oxide wear-resistant ceramic sheet and a silicon carbide wear-resistant ceramic sheet.

[0028] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, it also includes a shell that encloses the mover and the clamping module, and the shell includes two U-shaped upper shells and lower shells that cooperate with each other, and each upper shell and lower shell respectively includes a bottom wall and two side walls connected to the bottom wall, and the two side walls are arranged opposite to each other; the two ends of the mover pass through the bottom walls of the two upper shells and the lower shells.

[0029] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, the guide frame is connected and fixed to the shell.

[0030] Furthermore, in the above-mentioned inchworm-type piezoelectric motor, the deformation direction of the piezoelectric ceramic is consistent with the movement direction of the mover.

[0031] In a second aspect, the present application provides a driving method for the inchworm-type piezoelectric motor as described in the first aspect, and the inchworm-type piezoelectric motor can be driven by any one of the following driving modes: driving mode 1, driving mode 2, and driving mode 3:

[0032] Driving mode 1: stepping mode;

[0033] In a first time period, one of the at least two piezoelectric ceramics is energized to drive the mover to move in a first direction, and in a second time period, another of the at least two piezoelectric ceramics is energized, while the energized piezoelectric ceramic remains in a discharge state, so that the mover moves in a second direction, which is opposite to the first direction;

[0034] Driving mode 2: continuous motion mode;

[0035] Using two periodic voltage signals with a certain phase difference to drive the at least two piezoelectric ceramics respectively, so that the mover moves continuously;

[0036] Driving mode three: voltage mode;

[0037] At the same time, the at least two piezoelectric ceramics are energized, and by controlling the magnitude of the power supply voltage, the mover is caused to produce a micro displacement to achieve nm-level positioning accuracy.

[0038] Compared with the prior art, the present invention comprises: a mover; a plurality of clamping modules, each clamping module comprising: a flexible clamping hinge, the flexible clamping hinge contacts the mover to clamp the mover; the flexible clamping hinge is provided with a lower slope portion extending in a direction away from the center of the flexible clamping hinge at the left and right ends along the axial direction of the mover respectively; the flexible clamping hinge is provided with at least two first accommodating spaces; a guide frame, the guide frame is provided with a second accommodating space, the flexible clamping hinge is sleeved in the second accommodating space, and the flexible clamping hinge is connected to the guide frame; the guide frame is provided with a second accommodating space along the axial direction of the mover The left and right ends are provided with upper slope parts extending in the direction away from the center of the guide frame, so that the left and right ends of the first accommodating space along the axial direction of the mover are respectively extended into slope spaces at the left and right ends at the lower part of the upper slope part; piezoelectric ceramic, the piezoelectric ceramic is sleeved in the first accommodating space, and when the piezoelectric ceramic is energized and deformed and displaced, the lower slope part of the flexible clamping hinge is driven to fit with the upper slope part in the slope space, so that the upper slope part squeezes the lower slope part to apply a force pressing toward the axis center of the mover to the flexible clamping hinge, thereby clamping the mover, and the mover is moved by the accumulation of deformation of the piezoelectric ceramic. During the motion process of the first stepping mode and the second continuous mode of the present invention, a group of clamping modules can always be kept tightly clamping the mover, and sufficient thrust can be provided to drive the load to move; in addition, when a greater thrust is needed, two groups of clamping modules can be used at the same time, and the two groups of clamping modules are staggered in the time of applying voltage signals, such as a phase difference of π / 2, so that when the thrust becomes smaller at the falling edge of the signal of one group of clamping modules, the other group provides continuous and stable thrust. In the third voltage mode, by controlling the magnitude of the power supply voltage, a micro-displacement is generated to achieve nm-level positioning accuracy. The present invention aims to provide a piezoelectric ceramic-driven motion mechanism with long stroke, large thrust, high resolution, and high positioning accuracy, which can provide a high-precision linear motion solution for industries such as semiconductors, aerospace, and medical equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is an overall schematic diagram of an inchworm-type piezoelectric motor having a first clamping module according to an embodiment of the present invention;

[0040] Figure 2 is an exploded schematic diagram of an inchworm-type piezoelectric motor having a first clamping module according to an embodiment of the present invention;

[0041] Figure 3 1 is a schematic structural diagram of a first group of clamping modules of an inchworm-type piezoelectric motor containing a first type of clamping module according to an embodiment of the present invention;

[0042] Figure 4 1 is a schematic structural diagram of a second group of clamping modules of an inchworm-type piezoelectric motor including a first group of clamping modules according to an embodiment of the present invention;

[0043] Figure 5 is a schematic diagram of applying a first signal to an inchworm-type piezoelectric motor according to an embodiment of the present invention;

[0044] Figure 6 is a schematic diagram of applying a second signal to an inchworm-type piezoelectric motor according to an embodiment of the present invention;

[0045] Figure 7 It is a schematic diagram of the series connection of piezoelectric ceramics in the same module according to an embodiment of the present invention;

[0046] Figure 8 is a schematic diagram of a second clamping module according to an embodiment of the present invention;

[0047] Fig. 9 is a schematic diagram of a third clamping module according to an embodiment of the present invention.

[0048] In the accompanying drawings, the meanings of the reference numerals are as follows:

[0049] 1. mover; 2. first clamping module; 21. first flexible clamping hinge; 22. first guide frame; 231. first left piezoelectric ceramic; 232. first right piezoelectric ceramic; 3. second clamping module; 31. second flexible clamping hinge; 32. second guide frame; 331. second left piezoelectric ceramic; 332. second right piezoelectric ceramic; 4. third clamping module; 41. third flexible clamping hinge; 42. third guide frame; 431. third left piezoelectric ceramic; 432. third right piezoelectric ceramic; 5. fourth clamping module; 51. fourth flexible clamping hinge; 52. fourth guide frame; 531. fourth left piezoelectric ceramic; 532. fourth right piezoelectric ceramic; 6. upper housing; 7. lower housing; 8. lower slope; 9. upper slope; 10. deformation groove. DETAILED DESCRIPTION

[0050] In the following description, the present invention is described with reference to various embodiments. However, those skilled in the art will recognize that the embodiments may be implemented without one or more specific details or with other alternative and / or additional methods, materials or components. In other cases, well-known structures, materials or operations are not shown or described in detail to avoid obscuring the inventive point of the present invention. Similarly, for the purpose of explanation, specific quantities, materials and configurations are described to provide a comprehensive understanding of the embodiments of the present invention. However, the present invention is not limited to these specific details.

[0051] It should be noted that the components in the figures may be shown exaggeratedly for the sake of illustration and are not necessarily true to scale. In the figures, identical or functionally identical components are provided with the same reference numerals.

[0052] In the present invention, unless otherwise specified, "arranged on...", "arranged above..." and "arranged above..." do not exclude the existence of an intermediate between the two. In addition, "arranged on or above..." merely indicates the relative positional relationship between two components, and in certain cases, such as after reversing the product direction, it can also be converted into "arranged below or below...", and vice versa.

[0053] In the present invention, each embodiment is only intended to illustrate the aspects of the present invention and should not be construed as limiting.

[0054] In the present invention, unless otherwise specified, the quantifiers "a", "an" and "an" do not exclude the presence of a plurality of elements.

[0055] In the present invention, the term “connected” may refer to both being directly connected or being indirectly connected via an intermediate element.

[0056] In the present application, the term "configuration" refers to the setting of the shape, structure, material and / or function of the target object to achieve the desired technical effect, wherein "configuration" includes a variety of alternative technical means for achieving the technical effect, which become obvious under the teaching of the present application.

[0057] In this specification, reference to "one embodiment" or "the embodiment" means that a particular feature, structure, or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present invention. The phrase "in one embodiment" appearing in various places in this specification does not necessarily all refer to the same embodiment.

[0058] It should be noted that the embodiments of the present invention describe the process steps in a specific order, but this is only for the purpose of illustrating the specific embodiment, rather than limiting the order of the steps. On the contrary, in different embodiments of the present invention, the order of the steps can be adjusted according to the adjustment of the process.

[0059] like Figures 1 to 4 As shown, the present invention provides an inchworm-type piezoelectric motor, comprising: a mover 1; a plurality of clamping modules, each clamping module comprising: a flexible clamping hinge, a guide frame and piezoelectric ceramics.

[0060] The mover 1 is a displacement output element, used to fix the load and transmit the displacement generated by the motor, wherein the load may include: a lens, a slide, a silicon wafer, etc., and the mover can push or move the load. Optionally, the mover can be as follows Figures 1 to 4 The segmented mover shown in 8 may be as follows Fig. 9 The annular mover shown in the figure is a mover whose end is not connected to the end; the annular mover is a mover whose end is connected to the end. Figure 8As shown, the orthogonal clamping modules can be arranged in parallel according to the different structures of the movers; Fig. 9 As shown, the clamping modules can also be arranged in a circle to make the annular mover produce rotational motion.

[0061] Preferably, Figure 3 and 4 As shown, a deformation groove 10 is provided in a partial area of ​​each flexible clamp hinge, so that the flexible clamp hinge is easier to deform and the single-step displacement of the flexible clamp hinge is larger. The inner edge of the flexible clamp hinge is configured to contact with the mover 1 to clamp the mover 1. Figure 2 and 3 As shown, the first clamping module 2 is provided with a first flexible clamping hinge 21, the second clamping module 3 is provided with a second flexible clamping hinge 31, the third clamping module 4 is provided with a third flexible clamping hinge 31, and the fourth clamping module 5 is provided with a fourth flexible clamping hinge 51; each flexible clamping hinge is provided with a lower slope 8 extending in a direction away from the center of the flexible clamping hinge at the left and right ends along the axial direction of the mover; preferably, the angle between the slope surface of the lower slope 8 and the axial direction of the mover is an acute angle, for example, it can be an angle of 30 to 60 degrees, preferably it can be an angle of 45 degrees; each flexible clamping hinge is provided with at least two first accommodating spaces; the piezoelectric ceramic sleeve is arranged in the first accommodating space. In some embodiments, a wear-resistant material is also provided on the contact surface of the flexible clamping hinge that clamps the mover. Specifically, a piece of high-hardness wear-resistant material can be inlaid between the inner edge of the flexible clamping hinge and the contact surface of the mover. Optionally, the wear-resistant material includes: any one or any combination of zirconium oxide wear-resistant ceramic sheets, aluminum oxide wear-resistant ceramic sheets and silicon carbide wear-resistant ceramic sheets.

[0062] Preferably, Figures 1 to 4 As shown, the inchworm-type piezoelectric motor may include four clamping modules 2, 3, 4, and 5, with two clamping modules forming a group, and the clamping modules in a group are arranged opposite to each other along the radial direction of the mover; a first accommodation space is arranged at the left and right ends of the flexible clamping hinge of each clamping module, and a left piezoelectric ceramic is sleeved in the first accommodation space on the left side of each clamping module, and a right piezoelectric ceramic is sleeved in the first accommodation space on the right side of each clamping module. Optionally, as Figure 2 As shown, the two groups of clamp modules can be arranged perpendicular to each other; Figure 8 and 9 As shown, two groups of clamping modules can be arranged in parallel with each other. It should be pointed out here that this is only exemplary. Under the teachings of the present invention, other ways of changing the number and position of the clamping modules are conceivable. Preferably, in this solution, axially deformed piezoelectric ceramics can be used, and the deformation direction of the piezoelectric ceramics is consistent with the movement direction of the mover to prevent the piezoelectric ceramics from being subjected to shear force.

[0063] Specifically, Figure 3 and 4 As shown, the inchworm-type piezoelectric motor includes: first, second, third and fourth clamping modules 2, 3, 4, 5, wherein the first and second first clamping modules 2, 3 arranged opposite to each other along the radial direction of the mover 1 are the first group of clamping modules, and the third and fourth third clamping modules 4, 5 arranged opposite to each other along the radial direction of the mover are the second group of clamping modules; a first accommodating space is respectively arranged on the left and right sides of the flexible clamping hinge of each clamping module in the first, second, third and fourth clamping modules, and a piezoelectric ceramic is correspondingly sleeved in each first accommodating space, wherein the first accommodating space on the left side of the first clamping module is sleeved with the first left piezoelectric ceramic, and the first accommodating space on the right end of the first clamping module is sleeved with the first right piezoelectric ceramic, the end of the flexible clamping hinge of the first clamping module close to the first left piezoelectric ceramic is the first left end, and the end close to the first right piezoelectric ceramic is the first right end; the first accommodating space on the left side of the second clamping module A second left piezoelectric ceramic is sleeved, a second right piezoelectric ceramic is sleeved in the first accommodating space at the right end of the second clamping module, an end of the flexible clamping hinge of the second clamping module close to the second left piezoelectric ceramic is the second left end, and an end close to the second right piezoelectric ceramic is the second right end; a third left piezoelectric ceramic is sleeved in the first accommodating space at the left end of the third clamping module, a third right piezoelectric ceramic is sleeved in the first accommodating space at the right end of the third clamping module, an end of the flexible clamping hinge of the third clamping module close to the third left piezoelectric ceramic is the third left end, and an end close to the third right piezoelectric ceramic is the third right end; a fourth left piezoelectric ceramic is sleeved in the first accommodating space at the left end of the fourth clamping module, a fourth right piezoelectric ceramic is sleeved in the first accommodating space at the right end of the fourth clamping module, a left end of the flexible clamping hinge of the fourth clamping module close to the fourth piezoelectric ceramic is the fourth left end, and an end close to the fourth right piezoelectric ceramic is the fourth right end.

[0064] Specifically, if Figure 3 As shown, the first clamping module 2 has a first accommodation space at the left and right ends of the first flexible clamping hinge 21, and the first left piezoelectric ceramic 231 is sleeved in the first accommodation space on the left side of the first clamping module 2, and the first right piezoelectric ceramic 232 is sleeved in the first accommodation space on the right side of the first clamping module 2; the second clamping module 3 has a first accommodation space at the left and right ends of the second flexible clamping hinge 31, and the second left piezoelectric ceramic 331 is sleeved in the first accommodation space on the left end of the second clamping module 3, and the second right piezoelectric ceramic 332 is sleeved in the first accommodation space on the right end of the second clamping module 3. The first clamping module 2 has a first guide frame 22, and the second clamping module 3 has a second guide frame 32.

[0065] like Figure 4As shown, the third clamping module 4 has a first accommodation space at the left and right ends of the third flexible clamping hinge 31, and a third left piezoelectric ceramic 431 is sleeved in the first accommodation space on the left side of the third clamping module 4, and a third right piezoelectric ceramic 432 is sleeved in the first accommodation space on the right side of the third clamping module 4; the fourth clamping module 5 has a first accommodation space at the left and right ends of the fourth flexible clamping hinge 51, and a fourth left piezoelectric ceramic 531 is sleeved in the first accommodation space on the left end of the fourth clamping module 5, and a fourth right piezoelectric ceramic 532 is sleeved in the first accommodation space on the right end of the fourth clamping module 5. The third clamping module 4 has a third guide frame 42, and the fourth clamping module 5 has a fourth guide frame 52.

[0066] A second accommodating space is provided on each guide frame, and a flexible clamping hinge corresponding to each guide frame is sleeved in the second accommodating space, and the flexible clamping hinge is connected to the guide frame. Optionally, the middle part of the guide frame in the same clamping module can be fixed to the middle part of the flexible clamping hinge by bolts or other components, thereby providing a force point for the flexible clamping hinge.

[0067] Preferably, the size of the first accommodating space is larger than the outer contour size of the piezoelectric ceramic arranged therein, so as to reserve space for deformation and elongation of the piezoelectric ceramic in the first accommodating space; the size of the second accommodating space is larger than the outer contour size of the flexible clamping hinge arranged therein, so as to reserve space for deformation and elongation of the flexible clamping hinge in the second accommodating space.

[0068] Specifically, an upper slope portion 9 extending in a direction away from the center of the guide frame is provided at the left and right ends along the axial direction of the mover on each guide frame, so that the left and right ends of the first accommodating space along the axial direction of the mover extend into left and right end slope spaces respectively at the lower part of the upper slope portion 9; the angle between the slope surface of each slope space and the axial direction of the mover is an acute angle, and the size of the angle of each slope space is the same as the size of the angle between the slope surface of the corresponding lower slope portion 8 therein and the axial direction of the mover, for example, it can be an angle of 30 to 60 degrees, preferably an angle of 45 degrees; when the piezoelectric ceramic is energized and deformed, it drives the corresponding lower slope portion 8 of the flexible clamping hinge to fit with the upper slope portion 9 in the slope space, so that the upper slope portion 9 applies a force pressing toward the axis of the mover 1 to the flexible clamping hinge by squeezing the lower slope portion 8, and the movement of the mover is accumulated by a little deformation of the lower slope portion 8 of the flexible clamping hinge. Preferably, as Figure 3 and 4 As shown, the cross section of the guide frame is C-shaped, and the upper slope portion 9 is arranged at two free ends of the C-shaped cross section.

[0069] In some embodiments, Figure 1 and 2As shown, the present invention also includes: a housing enclosing the mover 1 and the first clamping modules 2, 3, 4, 5, the housing including two U-shaped upper housings 6 and lower housings 7 that cooperate with each other, each upper housing 6 and lower housing 7 respectively including a bottom wall and two side walls connected to the bottom wall, the two side walls are arranged oppositely; the two ends of the mover pass through the bottom walls of the upper housing 6 and the lower housing 7. The guide frame is connected and fixed to the housing. Specifically, bolt holes are respectively provided on the side of the guide frame and the bottom walls of the upper housing 6 and the lower housing 7, and the guide frame can be fixedly connected to the bottom walls of the upper housing 6 and the lower housing 7 respectively through the cooperation of the bolts and the bolt holes. The guide frame can be fixed on the housing, and the flexible clamping hinge is connected to the guide frame, and the guide frame provides a force point for the flexible clamping hinge. The upper and lower housings are used to encapsulate the various components of the motor and provide mounting holes for fixing the motor on the device frame of the actual application, and the device frame can be a device frame of a lens, a slide, a silicon wafer, etc. The first, second, third and fourth clamping modules 2, 3, 4, 5 are arranged in an array around the mover, two by two in a group, the first and second first clamping modules 2, 3 are a group, the third and fourth third clamping modules 4, 5 are a group, the first, second, third and fourth clamping modules 2, 3, 4, 5 can be driven and controlled by a voltage signal, and friction drives the mover 1 to produce displacement.

[0070] The clamping modules of the inchworm-type piezoelectric motor exist in pairs. In some embodiments, the inchworm-type piezoelectric motor may include two sets of orthogonal clamping modules, such as Figure 2 shown.

[0071] According to different stages or different working conditions, the inchworm-type piezoelectric motor of the present invention can be driven in three modes:

[0072] The first one, step mode, combines the clamping module with the stepping motion, which can provide a higher speed but pulsating motion;

[0073] The second, continuous mode, provides slower but continuous movement;

[0074] The third, voltage mode, provides tiny compensating movements.

[0075] In the first stepping mode of some embodiments of the present invention: in the first stage, the left piezoelectric ceramic of the first group of clamping modules is applied with a first voltage signal, and the left piezoelectric ceramic of the second group of clamping modules is kept in a non-powered state, and the flexible clamping hinge of the first group of clamping modules clamps the mover and holds the mover to move to the left; then in the second stage, the left piezoelectric ceramic of the first group of clamping modules is discharged, and at the same time, the left piezoelectric ceramic of the second group of clamping modules is applied with a second voltage signal, and the flexible clamping hinge of the second group of clamping modules clamps the mover and holds the mover to continue to move to the left;

[0076] For example, Figure 3 and 4As shown, in the first stage, the first left piezoelectric ceramic 231 of the first clamping module 2 and the second left piezoelectric ceramic 331 of the second clamping module 3 are simultaneously applied as follows: Figure 5 The first voltage signal Signal 1 is shown, while the third left piezoelectric ceramic 431 and the fourth left piezoelectric ceramic 531 are kept in a non-powered state; the first left piezoelectric ceramic 231 and the second left piezoelectric ceramic 331 generate Figure 3 As shown in the figure, the deformation displacement to the left promotes the deformation displacement of the first flexible clamping hinges 21 and 31 of the first clamping module 2 and the second clamping module 3. The lower slope 8 of the first left end of the first flexible clamping hinge 21 of the first clamping module 2 and the lower slope 8 of the second left end of the second flexible clamping hinge 31 of the second first clamping module 2 are respectively pressed against the corresponding left end slope space, so that the corresponding upper slope 9 applies a force to the axis of the mover 1 by squeezing the lower slope 8 to the flexible clamping hinges of the first clamping module 2 and the second clamping module 3. Under the action of pressure, the flexible clamping hinges of the first clamping module 2 and the second clamping module 3 clamp the mover and hold the mover to move to the left; in the second stage, the first left piezoelectric ceramic 231 of the first clamping module 2 and the second left piezoelectric ceramic 331 of the second clamping module are discharged at the same time, and at the same time, the third left piezoelectric ceramic 431 of the third clamping module 4 and the fourth left piezoelectric ceramic 531 of the fourth clamping module 5 are simultaneously applied as shown in the figure. Figure 5 As shown in the second voltage signal Signal 2, the third left piezoelectric ceramic 431 and the fourth left piezoelectric ceramic 531 generate Figure 4 The deformation displacement to the left as shown in the figure further promotes the deformation displacement of the third flexible clamping hinges 31 and 51 of the third clamping module 4 and the fourth clamping module 5. The lower slope portion 8 of the third left end of the third flexible clamping hinge 31 of the third clamping module 4 and the lower slope portion 8 of the fourth left end of the flexible clamping hinge 54 of the fourth clamping module 5 are respectively pressed against the corresponding left end slope space, so that the corresponding upper slope portion 9 applies a force pressing toward the axis of the mover 1 to the flexible clamping hinges of the third clamping module and the fourth clamping module by squeezing the lower slope portion 8. Under the action of pressure, the flexible clamping hinges of the third clamping module 4 and the fourth clamping module 5 clamp the mover and hold the mover, so that the mover continues to move to the left on the basis of the first stage; preferably, the first voltage signal Signal 1 and the second voltage signal Signal 2 include but are not limited to: sine wave, triangle wave, sawtooth wave, square wave and other forms.

[0077] Alternatively, similarly, Signal 1 and Signal 2 are applied to the clamping module of the first group and the clamping module of the second group respectively, and the mover can continue to move to the right. When the right piezoelectric ceramic of the clamping module of the first group is applied with a first voltage signal and the right piezoelectric ceramic of the clamping module of the second group remains in a non-powered state, the flexible clamping hinge of the first group of clamping modules clamps the mover and holds the mover to move to the right; the right piezoelectric ceramics of the first group of clamping modules discharge at the same time, and the right piezoelectric ceramics of the second group of clamping modules are applied with a second voltage signal, and the flexible clamping hinge of the second group of clamping modules clamps the mover and holds the mover to continue to move to the right. For example, Figure 3 and 4 As shown, in the first stage, the first right piezoelectric ceramic 232 of the first clamping module 2 and the second right piezoelectric ceramic 332 of the second clamping module 3 are simultaneously applied as follows: Figure 5 The first voltage signal Signal1 is shown, while the third right piezoelectric ceramic 432 and the fourth right piezoelectric ceramic 532 are kept in a non-powered state; the first right piezoelectric ceramic 232 and the second right piezoelectric ceramic 332 generate Figure 3 As shown in the rightward deformation displacement, the first flexible clamping hinges 21 and 31 of the first clamping module 2 and the second clamping module 3 are further pushed to deform and displace. The first right end lower slope portion 8 of the first flexible clamping hinge 21 of the first clamping module 2 and the second right end lower slope portion 8 of the second flexible clamping hinge 31 of the second clamping module 3 are respectively pressed against the corresponding right end slope space, so that the corresponding upper slope portion 9 applies a force pressing toward the axis of the mover 1 to the first flexible clamping hinges 21 and 31 of the first clamping module 2 and the second clamping module 3 by pressing down the lower slope 8. Under the action of pressure, the flexible clamping hinges of the first clamping module 2 and the second clamping module 3 clamp the mover and hold the mover to move to the right. In the second stage, the first right piezoelectric ceramic 232 of the first clamping module 2 and the second right piezoelectric ceramic 332 of the second clamping module 3 are discharged at the same time, and at the same time, the third right piezoelectric ceramic 432 of the third clamping module 4 and the fourth right piezoelectric ceramic 532 of the fourth clamping module 5 are simultaneously applied as shown in the figure. Figure 5 As shown in the second voltage signal Signal 2, the third right piezoelectric ceramic 432 and the fourth right piezoelectric ceramic 532 generate Figure 4The rightward deformation displacement shown in the figure further promotes the deformation displacement of the third flexible clamping hinges 31 and 51 of the third clamping module 4 and the fourth clamping module 5. The lower slope portion 8 of the third right end of the third flexible clamping hinge 31 of the third clamping module 4 and the lower slope portion 8 of the fourth right end of the fourth flexible clamping hinge 51 of the fourth clamping module 5 respectively abut against the corresponding right end slope space, so that the corresponding upper slope portion 9 applies a force pressing toward the axis center of the mover 1 to the third flexible clamping hinges 31 and 51 of the third clamping module 4 and the fourth clamping module 5 by squeezing the lower slope portion 8. Under the action of pressure, the flexible clamping hinge clamps 41 and 51 of the third clamping module 4 and the fourth clamping module 5 tighten the mover and clamp the mover to the right.

[0078] In the second continuous mode of some embodiments of the present invention, a leading voltage signal is applied to the left piezoelectric ceramic of the clamping modules of the same group, a lagging voltage signal is applied to the right piezoelectric ceramic of the clamping modules of the same group, and a phase difference exists between the leading voltage signal and the lagging voltage signal, such as the phase difference between the leading voltage signal and the lagging voltage signal may be π / 2, and the flexible clamping hinge of the clamping modules of the same group clamps the mover and holds the mover to move to the left; or, a leading voltage signal is applied to the right piezoelectric ceramic of the clamping modules of the same group, a lagging voltage signal is applied to the left piezoelectric ceramic of the clamping modules of the same group, and a phase difference exists between the leading voltage signal and the lagging voltage signal, such as the phase difference between the leading voltage signal and the lagging voltage signal is π / 2, and the flexible clamping hinge of the clamping modules of the same group clamps the mover and holds the mover to move to the right. Specifically, in the second continuous mode, taking the first and second first clamping modules 2 and 3 of the first group as an example, the left piezoelectric ceramics 231 and 331 of the first clamping modules 2 and 3 of the first group are powered at the same time, and the two left piezoelectric ceramics 231 and 331 generate Figure 3 The displacement to the left as shown pushes the deformation displacement of the clamping hinges 21, 31 of the first and second first clamping modules 2, 3 of the first group. Under the action of the upper slope 9 of the guide frame 22, 32 of the first group, the clamping hinges 21, 31 of the first group clamping modules 2, 3 clamp the mover and hold the mover to move to the left. Similarly, when the right piezoelectric ceramics 232, 332 of the first and second first clamping modules 2, 3 of the same group are powered at the same time, the mover is pushed to move to the right. If the left piezoelectric ceramics 231, 331 and the right piezoelectric ceramics 232, 332 of the first and second first clamping modules 2, 3 are driven respectively by two periodic voltage signals with a certain phase difference, namely, the leading voltage signal and the lagging voltage signal, such as the phase difference is π / 2; the mover will make continuous motion, and the leading voltage signal and the lagging voltage signal include but are not limited to: sine wave, triangle wave, sawtooth wave and square wave, such as Figure 6As shown, if the leading voltage signal Signal1 acts on the left piezoelectric ceramics 231 and 331 of the first and second first clamping modules 2 and 3, and the lagging voltage signal Signal2 acts on the right piezoelectric ceramics 232 and 332 of the first and second first clamping modules 2 and 3, the mover will move continuously to the left, otherwise, the mover will move continuously to the right. In some embodiments, if a greater thrust is required in an application scenario, the first and second first clamping modules 2 and 3 of the first group and the third and fourth third clamping modules 4 and 5 of the second group can work in the second continuous mode at the same time.

[0079] During the movement of the first stepping mode and the second continuous mode of the present invention, one group of clamping modules can always keep tightly clamping the mover, and can provide sufficient thrust to drive the load to move; in addition, when a larger thrust is needed, two groups of clamping modules can be used at the same time, and the two groups of clamping modules are staggered in the time of applying voltage signals, such as a phase difference of π / 2, so that when the signal of one group of clamping modules falls and the thrust becomes smaller, the other group provides continuous and stable thrust.

[0080] In the third voltage mode of some embodiments of the present invention, when the left piezoelectric ceramics of the same group of clamping modules are applied with voltage signals of different power supply voltages, the flexible clamping hinges of the group of clamping modules clamp the mover and hold the mover to the left for nm-level movement; specifically, in the third voltage mode, taking the first and second first clamping modules 2 and 3 of the first group as an example, the left piezoelectric ceramics 231 and 331 of the first and second first clamping modules 2 and 3 of the first group are powered at the same time, and the left piezoelectric ceramics 231 and 331 of the first and second first clamping modules 2 and 3 produce a displacement to the left as shown in Figure 3, pushing the deformation displacement of the clamping hinge, and under the action of the upper slope 9 of the guide frame, the first flexible clamping hinges 21 and 31 of the first and second first clamping modules 2 and 3 of the first group clamp the mover and hold the mover to the left for movement. In the third voltage mode of this embodiment, by controlling the magnitude of the power supply voltage, a micro displacement can be generated to achieve nm-level positioning accuracy.

[0081] More preferably, in the third voltage mode, due to the different elongation of the ceramics at different voltages, the pressure on the mover will also be different. In order to maintain the stability of the pressure during the process, it is necessary to control the voltage signal provided to the piezoelectric ceramic in a similar differential form. The specific implementation method takes the first clamping module 2 as an example: Figure 7 As shown, the positive electrode of the first left piezoelectric ceramic 231 is applied with the highest working voltage of the piezoelectric ceramic, the negative electrode of the first right piezoelectric ceramic 232 is grounded, and the negative electrode of the first left piezoelectric ceramic 231 and the positive electrode of the first right piezoelectric ceramic 232 are connected in series by a connecting wire 11, and a Figure 7A control voltage signal is applied to point c. When the control voltage changes, the first left piezoelectric ceramic 231 and the first right piezoelectric ceramic 232 still maintain a certain elongation length as a whole, so that the overall pressure on the mover remains unchanged, so that the motor driving force remains unchanged. The motor driving force remains unchanged, and the normal pre-tightening force of the flexible clamp hinge on the mover can be maintained through the upper slope to prevent the mover from slipping. The displacement size of the mover can be based on the voltage-based size change. By controlling the size of the supply voltage signal, a micro displacement is generated to achieve nm-level positioning accuracy.

[0082] Preferably, in this scheme, axially deformed piezoelectric ceramics can be used, and the deformation direction of the piezoelectric ceramics is consistent with the movement direction of the mover to prevent the piezoelectric ceramics from being subjected to shear force. At the same time, the inclined structure of the guide frame is utilized to make the deformation provided by the ceramics produce a component of positive pressure on the mover, and there is no need to use elastic elements or flexible hinges to provide the preload force required for the friction mover. The pressure on the mover is automatically provided during the movement. The greater the voltage, the greater the thrust, the greater the deformation, the tighter the contact, the greater the preload force, the greater the friction force on the mover, and thus the greater the thrust of the motor.

[0083] In summary, during the motion process of the first stepping mode and the second continuous mode of the present invention, a group of clamping modules can always be kept tightly clamped on the mover, and sufficient thrust can be provided to drive the load to move; in addition, when a greater thrust is needed, two groups of clamping modules can be used at the same time, and the two groups of clamping modules are staggered in the time of applying voltage signals, such as a phase difference of π / 2, so that when the thrust becomes smaller at the falling edge of the signal of one group of clamping modules, the other group provides a continuous and stable thrust. In the third voltage mode, by controlling the magnitude of the power supply voltage, a micro-displacement is generated to achieve nm-level positioning accuracy. The present invention aims to provide a piezoelectric ceramic-driven motion mechanism with long stroke, large thrust, high resolution, and high positioning accuracy, which can provide a high-precision linear motion solution for industries such as semiconductors, aerospace, and medical equipment.

[0084] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0085] Obviously, those skilled in the art can make various changes and modifications to the invention without departing from the spirit and scope of the invention. Thus, if these modifications and variations of the invention fall within the scope of the claims of the invention and their equivalents, the invention is also intended to include these modifications and variations.

Claims

1. A inchworm-type piezoelectric motor, characterized in that: include: mover; Multiple clamp modules, each clamp module includes: A flexible clamping hinge, the flexible clamping hinge contacts the mover to clamp the mover; The left and right ends of the flexible clamp hinge along the axial direction of the mover are respectively provided with lower slope portions extending in a direction away from the center of the flexible clamp hinge; at least two first accommodating spaces are provided on the flexible clamp hinge; A guide frame, wherein a second accommodating space is arranged on the guide frame, the flexible clamping hinge is sleeved in the second accommodating space, and the flexible clamping hinge is connected to the guide frame; an upper slope portion extending in a direction away from the center of the guide frame is arranged at the left and right ends of the guide frame along the axial direction of the mover, so that the left and right ends of the first accommodating space along the axial direction of the mover are respectively extended to form slope spaces at the left and right ends at the lower part of the upper slope portion; At least two piezoelectric ceramics are sleeved in the first accommodating space. When the piezoelectric ceramics are energized and deformed, the lower slope portion of the flexible clamping hinge is driven to fit with the upper slope portion in the slope space, so that the upper slope portion applies a force to the flexible clamping hinge toward the axis of the mover by squeezing the lower slope portion, thereby clamping the mover and moving the mover through the accumulation of the piezoelectric ceramic deformation.

2. The inchworm-type piezoelectric motor according to claim 1, characterized in that: The mover is a segmented mover or a ring-shaped mover; Preferably, the cross section of the guide frame is C-shaped, and the lower slope portions are arranged at two free ends of the C-shaped cross section.

3. The inchworm-type piezoelectric motor according to claim 1, characterized in that: The inchworm-type piezoelectric motor includes: 4 clamping modules, each two clamping modules form a group, and the clamping modules in a group are arranged opposite to each other along the radial direction of the mover; a first accommodating space is respectively provided at the left and right ends of the flexible clamping hinge of each clamping module, and a left piezoelectric ceramic is sleeved in the first accommodating space at the left end of each clamping module, and a right piezoelectric ceramic is sleeved in the first accommodating space at the right end of each clamping module.

4. The inchworm-type piezoelectric motor according to claim 3, characterized in that: When the left piezoelectric ceramic of the clamping module of the first group is applied with a first voltage signal and the left piezoelectric ceramic of the clamping module of the second group remains in a non-powered state, the flexible clamping hinge of the clamping module of the first group clamps the mover and holds the mover to move to the left; The left piezoelectric ceramic of the first clamping module is discharged, and at the same time, the left piezoelectric ceramic of the second clamping module is applied with a second voltage signal, and the flexible clamping hinge of the second clamping module clamps the mover and holds the mover to continue to move to the left; or, When the first voltage signal is applied to the right piezoelectric ceramic of the clamping module of the first group and the right piezoelectric ceramic of the clamping module of the second group remains in a non-powered state, the flexible clamping hinge of the clamping module of the first group clamps the mover and holds the mover to move rightward; The right piezoelectric ceramic of the first clamping module is discharged, and at the same time, the second voltage signal is applied to the right piezoelectric ceramic of the second clamping module. The flexible clamping hinge of the second clamping module clamps the mover and holds the mover to continue to move to the right.

5. The inchworm-type piezoelectric motor according to claim 3, characterized in that: The left piezoelectric ceramic of the clamping module of the same group is applied with a leading voltage signal, the right piezoelectric ceramic of the clamping module of the same group is applied with a lagging voltage signal, and there is a phase difference between the leading voltage signal and the lagging voltage signal, and the flexible clamping hinge of the clamping module of the same group clamps the mover and clamps the mover to move to the left; or, A leading voltage signal is applied to the right piezoelectric ceramic of the clamping module of the same group, and a lagging voltage signal is applied to the left piezoelectric ceramic of the clamping module of the same group, and there is a phase difference between the leading voltage signal and the lagging voltage signal. The flexible clamping hinge of the clamping module of the same group clamps the mover and holds the mover to move to the right.

6. The inchworm-type piezoelectric motor according to claim 3, characterized in that: When voltage signals with different power supply voltages are applied to the left piezoelectric ceramics of the same group of clamping modules, the flexible clamping hinges of the group of clamping modules clamp the mover and hold the mover to move to the left at the nm level; When voltage signals of different power supply voltages are applied to the right piezoelectric ceramics of the same group of clamping modules, the flexible clamping hinges of the group of clamping modules clamp the mover and hold the mover to move rightward at the nm level.

7. The inchworm-type piezoelectric motor according to claim 6, characterized in that: The positive electrode of the left piezoelectric ceramic of each clamping module is applied with the highest working voltage of the piezoelectric ceramic, the negative electrode of the right piezoelectric ceramic of each clamping module is grounded, the negative electrode of the left piezoelectric ceramic and the positive electrode of the right piezoelectric ceramic of each clamping module are connected in series through a connecting line, and a voltage signal is applied to the connecting line.

8. The inchworm-type piezoelectric motor according to claim 3, characterized in that: Two sets of clamping modules are arranged perpendicularly or parallel to each other; Preferably, a deformation groove is provided in a partial area of ​​the flexible clamping hinge; More preferably, the size of the first accommodating space is larger than the outer contour size of the piezoelectric ceramic, so as to reserve space for deformation and elongation of the piezoelectric ceramic; the size of the second accommodating space is larger than the outer contour size of the flexible clamping hinge, so as to reserve space for deformation and elongation of the flexible clamping hinge; More preferably, a wear-resistant material is provided on the contact surface of the flexible clamp hinge that clamps the mover; More preferably, the wear-resistant material comprises: any one of a zirconium oxide wear-resistant ceramic sheet, an aluminum oxide wear-resistant ceramic sheet and a silicon carbide wear-resistant ceramic sheet.

9. The inchworm-type piezoelectric motor according to claim 1, characterized in that: It also includes a housing enclosing the mover and the clamp module, the housing including two U-shaped upper and lower housings that cooperate with each other, each upper and lower housing including a bottom wall and two side walls connected to the bottom wall, the two side walls are arranged oppositely; the two ends of the mover pass through the bottom walls of the two upper and lower housings; Preferably, the guide frame is connected and fixed to the housing; More preferably, the deformation direction of the piezoelectric ceramic is consistent with the movement direction of the mover.

10. The driving method of the inchworm type piezoelectric motor according to any one of claims 1 to 9, characterized in that: The inchworm-type piezoelectric motor can be driven by any one of the following driving modes: driving mode 1, driving mode 2, and driving mode 3: Driving mode 1: stepping mode; In a first time period, one of the at least two piezoelectric ceramics is energized to drive the mover to move in a first direction, and in a second time period, another of the at least two piezoelectric ceramics is energized, while the energized piezoelectric ceramic remains in a discharge state, so that the mover moves in a second direction, which is opposite to the first direction; Driving mode 2: continuous motion mode; Using two periodic voltage signals with a certain phase difference to drive the at least two piezoelectric ceramics respectively, so that the mover moves continuously; Driving mode three: voltage mode; At the same time, the at least two piezoelectric ceramics are energized, and the magnitude of the power supply voltage is controlled to cause the mover to produce a micro displacement to achieve nm-level positioning accuracy.

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