Inchworm piezoelectric drive motor and control method thereof

Abstract

This invention discloses a inchworm-type piezoelectric drive motor and its control method, comprising a base assembly, a displacement platform assembly, a guide rail assembly, and a drive assembly. The drive assembly includes an elastic element, a first piezoelectric ceramic, a second piezoelectric ceramic, a third piezoelectric ceramic, a first friction plate, a second friction plate, and a friction strip. The elastic element is mounted on the base assembly, and the piezoelectric ceramics and friction plates are mounted on the elastic element. The friction strip is mounted on the displacement platform assembly. When the first piezoelectric ceramic is de-energized, the first friction plate contacts the friction strip and maintains a certain frictional force. When the first piezoelectric ceramic is energized and extends, the first friction plate disengages from the friction strip. When the third piezoelectric ceramic is de-energized, the second friction plate contacts the friction strip and maintains a certain frictional force. When the third piezoelectric ceramic is energized and extends, the second friction plate disengages from the friction strip. The piezoelectric drive motor of this invention has good motion stability, a simple drive waveform, high resolution, self-locking capability, and a long stroke.

Description

Technical Field

[0001] This invention relates to the field of piezoelectric drive motor technology, and in particular to a inchworm-type piezoelectric drive motor and its control method. Background Technology

[0002] A piezoelectric motor is a precision actuator that converts electrical energy into mechanical energy using the inverse piezoelectric effect of a piezoelectric element, enabling micro- and nano-scale displacement. In existing technologies, linear platforms capable of providing high-precision displacement already exist, mainly categorized into piezoelectric stick-slip motors and pure piezoelectric motors. Piezoelectric stick-slip motors suffer from poor motion stability. Pure piezoelectric motors suffer from short stroke. How to provide a motor with good motion stability, simple drive waveform, high resolution, and long stroke is a pressing technical problem to be solved in this field. Summary of the Invention

[0003] Therefore, the present invention provides a inchworm-type piezoelectric drive motor and its control method, which has good motion stability, simple drive waveform, high resolution, self-locking capability and long stroke.

[0004] To solve the above-mentioned technical problems, the present invention provides a inchworm-type piezoelectric drive motor, comprising: Base assembly; A displacement platform assembly is located on one side of the base assembly along the z-axis direction; A guide rail assembly is connected between the base assembly and the displacement platform assembly, and is used to guide the displacement platform assembly to translate relative to the base assembly along the x-axis direction, wherein the x-axis direction is perpendicular to the z-axis direction; A driving assembly, disposed between the base assembly and the displacement platform assembly, includes an elastic element, a first piezoelectric ceramic, a second piezoelectric ceramic, a third piezoelectric ceramic, a first friction plate, a second friction plate, and a friction strip. The elastic element is mounted on the base assembly. The first, second, and third piezoelectric ceramics are sequentially mounted on the elastic element along the x-axis. The first and third piezoelectric ceramics can extend and retract along the x-axis, and the second piezoelectric ceramic can extend and retract along the y-axis. The y-axis is perpendicular to both the z-axis and the x-axis. The first friction plate is disposed on the first piezoelectric ceramic along the x-axis. The second friction plate is located on the side of the third piezoelectric ceramic along the y-axis direction; the friction strip is mounted on the displacement platform assembly and located on the side of the elastic element along the y-axis direction, and the friction strip extends along the x-axis direction. When the first piezoelectric ceramic is de-energized, the first friction plate contacts the friction strip and maintains a certain frictional force. When the first piezoelectric ceramic is energized and elongates, the first friction plate disengages from the friction strip. When the third piezoelectric ceramic is de-energized, the second friction plate contacts the friction strip and maintains a certain frictional force. When the third piezoelectric ceramic is energized and elongates, the second friction plate disengages from the friction strip.

[0005] In one embodiment of the present invention, each of the driving components includes two friction strips, two first friction plates, and two second friction plates. The two friction strips are symmetrically disposed on both sides of the elastic element along the y-axis direction. The two first friction plates are respectively disposed on both sides of the first piezoelectric ceramic along the y-axis direction and respectively cooperate with the two friction strips. The two second friction plates are respectively disposed on both sides of the third piezoelectric ceramic along the y-axis direction and respectively cooperate with the two friction strips.

[0006] In one embodiment of the present invention, the inchworm-type piezoelectric drive motor includes two drive components arranged at intervals along the y-axis direction.

[0007] In one embodiment of the present invention, the elastic member is provided with a first ceramic mounting groove, a second ceramic mounting groove and a third ceramic mounting groove arranged sequentially along the x-axis direction, and the first piezoelectric ceramic, the second piezoelectric ceramic and the third piezoelectric ceramic are respectively disposed in the first ceramic mounting groove, the second ceramic mounting groove and the third ceramic mounting groove.

[0008] In one embodiment of the present invention, the base assembly includes a base and an elastic element mounting plate. The base is provided with a drive component mounting groove. The drive component mounting groove has a bottom in the z-axis direction, two end walls in the x-axis direction, and two side walls in the y-axis direction. The height of the end walls protruding from the bottom of the groove is lower than the height of the side walls protruding from the bottom of the groove. A step is provided at one end of the side wall away from the bottom of the groove. The elastic element mounting plate is fixed to one end of the bottom of the groove. The guide rail assembly includes two fixed guide members and two moving guide members. The two fixed guide members are respectively installed on the steps of the two side walls. At least one fixed guide member is installed on the step in an adjustable position along the y-axis direction. The two moving guide members are installed on the displacement platform assembly and cooperate with the two fixed guide members respectively. The drive assembly is located between the elastic element mounting plate and the bottom of the groove, and the elastic element is mounted on the elastic element mounting plate.

[0009] In one embodiment of the present invention, the displacement platform assembly includes a displacement platform and a friction strip mounting base. The friction strip mounting base is connected to the side of the displacement platform near the base assembly along the z-axis direction, and the friction strip mounting base is positionally adjustable to the displacement platform along the y-axis direction. The same drive assembly includes two friction strips, and at least one friction strip of the same drive assembly is fixed to the friction strip mounting base.

[0010] In one embodiment of the present invention, the displacement platform has a protrusion on the side of the base assembly along the z-axis direction; Of the two friction strips in the same drive assembly, one is mounted on the protrusion and the other is mounted on the friction strip mounting base.

[0011] In one embodiment of the present invention, the inchworm-type piezoelectric drive motor further includes a detection component, which includes a grating ruler and a grating data reading device. The grating ruler is fixed relative to the displacement platform component, and the grating data reading device is fixed on the base component.

[0012] The present invention also provides a control method for controlling the inchworm-type piezoelectric drive motor, comprising the following steps: S11. The first piezoelectric ceramic, the second piezoelectric ceramic, and the third piezoelectric ceramic are all de-energized. The first friction plate is in contact with the friction strip and maintains a certain friction force. The second friction plate is in contact with the friction strip and maintains a certain friction force. S12. Control the first piezoelectric ceramic to extend when energized, and the first friction piece disengages from the friction strip; S13. Control the second piezoelectric ceramic to extend when energized, causing the second friction plate to move away from the first friction plate along the x-axis, thereby driving the displacement platform assembly to move forward through the friction strip; S14. Control the first piezoelectric ceramic to de-energize and shorten, and the first friction piece contacts the friction strip and maintains a certain friction force; S15. Control the third piezoelectric ceramic to extend when energized, and the second friction piece disengages from the friction strip; S16. Control the second piezoelectric ceramic to de-energize and shorten, causing the first friction plate to move along the x-axis towards the second friction plate, thereby driving the displacement platform assembly to move forward through the friction strip; S17. Control the third piezoelectric ceramic to de-energize and shorten, end the control or return to step S12.

[0013] The present invention also provides a control method for controlling the aforementioned inchworm-type piezoelectric drive motor, the control method comprising the following steps: S21. The first piezoelectric ceramic, the second piezoelectric ceramic, and the third piezoelectric ceramic are all de-energized. The first friction plate is in contact with the friction strip and maintains a certain friction force. The second friction plate is in contact with the friction strip and maintains a certain friction force. S22. Control the third piezoelectric ceramic to extend when energized, and the second friction piece disengages from the friction strip; S23. Control the second piezoelectric ceramic to extend when energized, causing the first friction piece to move away from the second friction piece along the x-axis, and then drive the displacement platform assembly to move in the opposite direction through the friction strip; S24. The third piezoelectric ceramic is de-energized and shortened, and the second friction plate contacts the friction strip and maintains a certain frictional force. S25. Control the first piezoelectric ceramic to extend when energized, and the first friction piece disengages from the friction strip; S26. Control the second piezoelectric ceramic to de-energize and shorten, causing the second friction plate to move along the x-axis towards the first friction plate, and then drive the displacement platform assembly to move in the opposite direction through the friction strip; S27. Control the first piezoelectric ceramic to de-energize and shorten, end the control or return to step S22.

[0014] Compared with the prior art, the above-mentioned technical solution of the present invention has the following advantages: The inchworm-type piezoelectric drive motor and its control method of the present invention include a base assembly, a displacement platform assembly, a guide assembly, and a drive assembly. The drive assembly includes an elastic element, a first piezoelectric ceramic, a second piezoelectric ceramic, a third piezoelectric ceramic, a first friction plate, a second friction plate, and a friction strip. First, by controlling the piezoelectric ceramic, the first and second friction plates alternately push the friction strip to move horizontally, thereby achieving continuous and stable linear motion of the piezoelectric drive motor in an inchworm-like motion. Second, the expansion and contraction of the piezoelectric ceramic is proportional to the amplitude of the drive voltage, resulting in a simple drive waveform. Third, during the movement, the displacement between the friction pairs is transmitted through static friction, directly transmitting the micro-nano-level displacement of the piezoelectric ceramic to the displacement platform assembly, giving the piezoelectric drive motor high resolution. Moreover, the piezoelectric drive motor can achieve self-locking after the piezoelectric ceramic is de-energized. In addition, the long stroke requirement of the displacement platform assembly can be achieved after multiple expansions and contractions of the piezoelectric ceramic. Attached Figure Description

[0015] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0016] Figure 1 This is a schematic diagram of the appearance of the inchworm-type piezoelectric drive motor disclosed in this invention; Figure 2 This is a cross-sectional view of the inchworm-type piezoelectric drive motor disclosed in this invention; Figure 3 This is an exploded view of the inchworm-type piezoelectric drive motor disclosed in this invention; Figure 4 This is a schematic diagram of the drive assembly of the inchworm-type piezoelectric drive motor disclosed in this invention.

[0017] Explanation of reference numerals in the accompanying drawings: 1. Base assembly; 11. Base; 111. Groove bottom; 112. End wall; 113. Side wall; 114. Step; 12. Elastic element mounting plate; Displacement platform assembly; 21. Displacement platform; 211. Protrusion; 22. Friction strip mounting base; 23. Friction strip mounting base adjustment end; 24. Friction strip mounting base fixing screw; 3. Guide rail assembly; 31. Fixed guide component; 32. Motion guide component; 33. Fixed guide component fixing screw; 34. Guide rail adjusting end; 35. Motion guide component fixing screw; 4. Drive assembly; 41. Elastic element; 411. Fixing point; 42. First piezoelectric ceramic; 43. Second piezoelectric ceramic; 44. Third piezoelectric ceramic; 45. First friction plate; 46. Second friction plate; 47. Friction strip; 48. Friction pair; 51. Grating ruler; 52. Grating data reading device. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0019] See Figures 1 to 4 As shown, this invention discloses an embodiment of the inchworm-type piezoelectric drive motor.

[0020] Inchworm-type piezoelectric drive motors include: Base component 1; The displacement platform assembly 2 is located on one side of the base assembly 1 along the z-axis direction; The guide rail assembly 3 is connected between the base assembly 1 and the displacement platform assembly 2, and is used to guide the displacement platform assembly 2 to translate relative to the base assembly 1 along the x-axis direction, wherein the x-axis direction is perpendicular to the z-axis direction. Drive assembly 4, disposed between the base assembly 1 and the displacement platform assembly 2, includes an elastic element 41, a first piezoelectric ceramic 42, a second piezoelectric ceramic 43, a third piezoelectric ceramic 44, a first friction plate 45, a second friction plate 46, and a friction strip 47. The elastic element 41 is mounted on the base assembly 1. The first piezoelectric ceramic 42, the second piezoelectric ceramic 43, and the third piezoelectric ceramic 44 are sequentially mounted on the elastic element 41 along the x-axis direction. The first piezoelectric ceramic 42 and the third piezoelectric ceramic 44 can extend and retract along the x-axis direction, and the second piezoelectric ceramic 43 can extend and retract along the y-axis direction. The y-axis direction is perpendicular to the z-axis direction and the x-axis direction. The first friction plate 45 is disposed on the first piezoelectric ceramic 42 along the x-axis direction. On the side of the aforementioned y-axis direction, the aforementioned second friction plate 46 is disposed on the side of the aforementioned third piezoelectric ceramic 44 along the aforementioned y-axis direction, the aforementioned friction strip 47 is mounted on the aforementioned displacement platform assembly 2 and located on the side of the aforementioned elastic member 41 along the aforementioned y-axis direction, the aforementioned friction strip 47 extends along the aforementioned x-axis direction, when the aforementioned first piezoelectric ceramic 42 is de-energized, the aforementioned first friction plate 45 contacts the aforementioned friction strip 47 and maintains a certain friction force, when the aforementioned first piezoelectric ceramic 42 is energized and extends, the aforementioned first friction plate 45 disengages from the aforementioned friction strip 47, when the aforementioned third piezoelectric ceramic 44 is de-energized, the aforementioned second friction plate 46 contacts the aforementioned friction strip 47 and maintains a certain friction force, when the aforementioned third piezoelectric ceramic 44 is energized and extends, the aforementioned second friction plate 46 disengages from the aforementioned friction strip 47.

[0021] Specifically, the base assembly 1 serves as the mounting reference for the entire machine and bears all static and dynamic loads.

[0022] The displacement platform component 2 is the motion output end of the motor, which ultimately drives the load to move along the x-axis.

[0023] The guide rail assembly 3 defines a single direction of motion (x-axis direction) to ensure that the displacement platform assembly 2 moves linearly without offset.

[0024] The drive assembly transmits power through the extension and friction of piezoelectric ceramics. The elastic element 41 is fixed to the base assembly 1 via multiple evenly distributed fixing points 411. The deformation of the elastic element 41 causes a change in the position of the first friction plate 45 and the second friction plate 46. The first piezoelectric ceramic 42, the second piezoelectric ceramic 43, and the third piezoelectric ceramic 44 extend and contract, causing the elastic element 41 to deform, thereby changing the position of the first friction plate 45 and the second friction plate 46. The first friction plate 45 and the second friction plate 46 are respectively fixed to the y-axis direction sides of the first piezoelectric ceramic 42 and the third piezoelectric ceramic 44, thus enabling position changes during the extension and contraction of the first piezoelectric ceramic 42, the second piezoelectric ceramic 43, and the third piezoelectric ceramic 44. The friction strip 47 converts all micro-motions into linear motion.

[0025] When the first piezoelectric ceramic 42 is de-energized, the first friction piece 45 adheres to the friction strip 47 to form a friction pair 48 (static friction lock, the first friction piece 45 and the friction strip 47 do not move relative to each other); when the first piezoelectric ceramic 42 is energized and elongates (along the x-axis direction), the first friction piece 45 disengages from the friction strip 47 (no friction, the first friction piece 45 can move freely relative to the friction strip 47).

[0026] When the third piezoelectric ceramic 44 is de-energized, the second friction piece 46 adheres tightly to the friction strip 47 to form a friction pair 48 (static friction locks the second friction piece 46 and the friction strip 47 without relative movement); when the third piezoelectric ceramic 44 is energized and elongates (along the x-axis direction), the second friction piece 46 disengages from the friction strip 47 (no friction, the second friction piece can move freely relative to the friction strip 47).

[0027] When the aforementioned displacement platform assembly 2 moves in the positive direction along the x-axis, the control method for the aforementioned inchworm-type piezoelectric drive motor includes the following steps: S11, the first piezoelectric ceramic 42, the second piezoelectric ceramic 43 and the third piezoelectric ceramic 44 are all de-energized, the first friction plate 45 is in contact with the friction strip 47 and maintains a certain friction force, and the second friction plate 46 is in contact with the friction strip 47 and maintains a certain friction force. S12. Control the first piezoelectric ceramic 42 to extend when energized, and the first friction piece 45 separates from the friction strip 47. S13. Control the second piezoelectric ceramic 43 to extend when energized, thereby driving the second friction plate 46 to move away from the first friction plate 45 along the x-axis, and then driving the displacement platform assembly 2 to move forward through the friction strip 47. S14. Control the first piezoelectric ceramic 42 to de-energize and shorten, so that the first friction piece 45 contacts the friction strip 47 and maintains a certain friction force. S15. Control the third piezoelectric ceramic 44 to extend when energized, and the second friction piece 46 separates from the friction strip 47. S16. Control the second piezoelectric ceramic 43 to de-energize and shorten, thereby driving the first friction plate 45 to move along the x-axis towards the second friction plate 46, and then driving the displacement platform assembly 2 to move forward through the friction strip 47. S17. Control the third piezoelectric ceramic 44 to de-energize and shorten, end the control or return to step S12. When the displacement platform assembly 2 moves in the opposite direction along the x-axis, the control method of the inchworm-type piezoelectric drive motor includes the following steps: S21, the first piezoelectric ceramic 42, the second piezoelectric ceramic 43 and the third piezoelectric ceramic 44 are all de-energized, the first friction plate 45 is in contact with the friction strip 47 and maintains a certain friction force, and the second friction plate 46 is in contact with the friction strip 47 and maintains a certain friction force. S22. Control the third piezoelectric ceramic 44 to extend when energized, and the second friction piece 46 separates from the friction strip 47. S23. Control the second piezoelectric ceramic 43 to extend when energized, thereby driving the first friction plate 45 to move away from the second friction plate 46 along the x-axis, and then driving the displacement platform assembly 2 to move in the opposite direction through the friction strip 47. S24. The third piezoelectric ceramic 44 is de-energized and shortens, and the second friction piece 46 contacts the friction strip 47 and maintains a certain friction force. S25. Control the first piezoelectric ceramic 42 to extend when energized, and the first friction piece 45 separates from the friction strip 47. S26. Control the second piezoelectric ceramic 43 to de-energize and shorten, thereby driving the second friction plate 46 to move along the x-axis towards the direction of the first friction plate 45, and then driving the displacement platform assembly 2 to move in the opposite direction through the friction strip 47. S27. Control the first piezoelectric ceramic 42 to shorten by de-energizing, end the control or return to step S22.

[0028] Specifically, the forward motion completes one cycle according to S12→S13→S14→S15→S16→S17. After S17, it returns directly to S12. One six-step cycle achieves two forward micro-displacements (once each in S13 and S16). The cycle achieves continuous forward motion. The more cycles, the longer the forward movement of the displacement platform component 2. The reverse motion completes one cycle according to S22→S23→S24→S25→S26→S27. After S27, it returns directly to S22. One six-step cycle achieves two reverse micro-displacements (once each in S23 and S36). The cycle achieves continuous reverse motion. The more cycles, the longer the reverse movement of the displacement platform component 2.

[0029] In S11, the first piezoelectric ceramic 42, the second piezoelectric ceramic 43, and the third piezoelectric ceramic 44 are all de-energized, and the first friction plate 45 and the second friction plate 46 lock the friction strip 47, so the displacement platform assembly remains stationary (starting reference). In S12, only the first piezoelectric ceramic 42 is energized and extends, while the first friction plate 45 is unlocked and disengaged. In S13, the first piezoelectric ceramic 42 remains energized and extends, the second piezoelectric ceramic 43 begins to extend, and the third piezoelectric ceramic 44 remains de-energized. Using the second friction plate 46 as a fulcrum, the displacement platform assembly 2 is pushed to complete the first positive displacement. In S14, the second piezoelectric ceramic 43 remains energized and extends, while the first piezoelectric ceramic 42 is de-energized and retracts. In S15, the first piezoelectric ceramic 42 remains de-energized, the second piezoelectric ceramic 43 remains energized and extended, the third piezoelectric ceramic 44 is energized and extended, and the second friction plate 46 is unlocked and disengaged. In S16, the first piezoelectric ceramic 42 remains de-energized, the third piezoelectric ceramic 44 remains energized and extended, the second piezoelectric ceramic 43 is de-energized and shortened and reset, and the displacement platform assembly 2 completes the second forward displacement. In S17, the third piezoelectric ceramic 44 is de-energized and shortened, the first friction plate 45 and the second friction plate 46 both lock the friction strip 47, and the displacement platform assembly remains stationary.

[0030] Similarly, in S21, the first piezoelectric ceramic 42, the second piezoelectric ceramic 43, and the third piezoelectric ceramic 44 are all de-energized, and the first friction plate 45 and the second friction plate 46 lock the friction strip 47, so the displacement platform assembly remains stationary (starting reference); in S22, only the third piezoelectric ceramic 44 is energized and extends, while the second friction plate 46 is unlocked and disengaged; in S23, the third piezoelectric ceramic 44 remains energized and extends, the second piezoelectric ceramic 43 begins to be energized and extends, the first piezoelectric ceramic 42 remains de-energized, and the displacement platform assembly 2 is pushed to complete the first reverse displacement using the first friction plate 45 as a fulcrum; in S24, the second piezoelectric ceramic 43 remains energized and extends, while the third piezoelectric ceramic 44 is de-energized. In S25, the first piezoelectric ceramic 42 remains de-energized, the second friction plate 46 is re-locked, and the position of the displacement platform assembly 2 is fixed; in S26, the third piezoelectric ceramic 44 remains de-energized, the second piezoelectric ceramic 43 remains energized and extended, the first piezoelectric ceramic 42 is energized and extended, and the first friction plate 45 is unlocked and disengaged; in S27, the first piezoelectric ceramic 42 is de-energized and shortened, the first friction plate 45 remains energized and extended, the second piezoelectric ceramic 43 is de-energized and shortened and reset, and the displacement platform assembly 2 completes the second reverse displacement; in S28, the first piezoelectric ceramic 42 is de-energized and shortened, the first friction plate 45 and the second friction plate 46 both lock the friction strip 47, and the displacement platform assembly remains stationary.

[0031] Through the above technical solution, the piezoelectric drive motor includes a base assembly, a displacement platform assembly, a guide assembly, and a drive assembly. The drive assembly includes an elastic element, a first piezoelectric ceramic, a second piezoelectric ceramic, a third piezoelectric ceramic, a first friction plate, a second friction plate, and a friction strip. First, by controlling the piezoelectric ceramic, the first and second friction plates alternately push the friction strip horizontally, achieving continuous and stable linear motion of the piezoelectric drive motor in a inchworm-like motion. Second, the expansion and contraction of the piezoelectric ceramic is proportional to the amplitude of the drive voltage, resulting in a simple drive waveform. Third, during the movement, the displacement between the friction pairs is transmitted through static friction, directly transmitting the micro-nano-level displacement of the piezoelectric ceramic to the displacement platform assembly, giving the piezoelectric drive motor high resolution. Moreover, the piezoelectric ceramic can achieve self-locking when all power is cut off, and the long stroke requirement of the displacement platform assembly can be met after multiple expansions and contractions of the piezoelectric ceramic.

[0032] In this embodiment, each of the aforementioned driving components 4 includes two friction strips 47, two first friction plates 45, and two second friction plates 46. The two friction strips 47 are symmetrically arranged on both sides of the elastic member 41 along the y-axis direction. The two first friction plates 45 are respectively arranged on both sides of the first piezoelectric ceramic 42 along the y-axis direction and respectively cooperate with the two friction strips 47. The two second friction plates 46 are respectively arranged on both sides of the third piezoelectric ceramic 44 along the y-axis direction and respectively cooperate with the two friction strips 47.

[0033] Specifically, two friction strips 47 are symmetrically arranged on both sides of the elastic element 41, and are fixed relative to the displacement platform assembly 2, serving as reference elements for double-sided friction engagement. The elastic element 41 is precisely embedded in the gap between the two friction strips 47. Two first friction plates 45 are symmetrically arranged on both sides of the first piezoelectric ceramic 42 along the y-axis, respectively engaging with the friction strips 47 on both sides. Two second friction plates 46 are symmetrically arranged on both sides of the third piezoelectric ceramic 44 along the y-axis, respectively engaging with the friction strips 47 on both sides. The engagement gap and contact pressure between the first friction plates 45 and the friction strips 47 on both sides are completely consistent, ensuring equal force on both sides.

[0034] Through the above technical solution, each driving component includes two first friction plates, two second friction plates, and two friction strips. By moving multiple friction pairs simultaneously, the displacement platform component of the present invention achieves greater load capacity and higher efficiency.

[0035] In this embodiment, the inchworm-type piezoelectric drive motor includes two drive components 4 arranged at intervals along the y-axis.

[0036] Specifically, the two drive components include two elastic elements 41, two first piezoelectric ceramics 42, two second piezoelectric ceramics 43, two third piezoelectric ceramics 44, four first friction plates 45, four second friction plates, and four friction strips 47, realizing dual drive and quadruple friction pairs.

[0037] By using the above technical solution, and by setting up two drive components, the displacement platform component can be translated simultaneously through dual drives and four friction pairs, thus achieving linear motion under large loads.

[0038] In this embodiment, the elastic element 41 is provided with a first ceramic mounting groove, a second ceramic mounting groove and a third ceramic mounting groove arranged sequentially along the x-axis direction. The first piezoelectric ceramic 42, the second piezoelectric ceramic 43 and the third piezoelectric ceramic 44 are respectively disposed in the first ceramic mounting groove, the second ceramic mounting groove and the third ceramic mounting groove.

[0039] By using the above technical solution, the piezoelectric ceramic is installed in the groove of the elastic element, which is more conducive to driving the elastic element to deform.

[0040] In one embodiment of the present invention, the base assembly 1 includes a base 11 and an elastic element mounting plate 12. The base 11 is provided with a drive component mounting groove. The drive component mounting groove has a groove bottom 111 in the z-axis direction, two end walls 112 in the x-axis direction, and two side walls 113 in the y-axis direction. The height of the end walls 112 protruding from the groove bottom 111 is lower than the height of the side walls 113 protruding from the groove bottom 111. A step 114 is provided at one end of the side walls 113 away from the groove bottom 111. The elastic element mounting plate 12 is fixed to one end of the groove bottom 111 near the displacement platform assembly 2. The guide rail assembly 3 includes two fixed guide members 31 and two moving guide members 32. The two fixed guide members 31 are respectively installed on the steps 114 of the two side walls 113. At least one fixed guide member 31 is installed on the step 114 in an adjustable position along the y-axis direction. The two moving guide members 32 are installed on the displacement platform assembly 2 and cooperate with the two fixed guide members 31 respectively. The aforementioned drive assembly 4 is disposed between the aforementioned elastic element mounting plate 12 and the aforementioned groove bottom 111, and the aforementioned elastic element 41 is mounted on the aforementioned elastic element mounting plate 12.

[0041] In this embodiment, the displacement platform assembly 2 includes a displacement platform 21 and a friction strip mounting base 22. The friction strip mounting base 22 is connected to the side of the displacement platform 21 along the z-axis direction close to the base assembly 1. The position of the friction strip mounting base 22 along the y-axis direction is adjustable to the displacement platform 21. The same drive assembly 4 includes two friction strips 47, and at least one friction strip 47 of the same drive assembly 4 is fixed to the friction strip mounting base 22.

[0042] In this embodiment, the displacement platform 21 is provided with a protrusion 211 on the side of the base assembly 1 along the z-axis direction; Of the two friction strips 47 of the same drive assembly 4, one is mounted on the protrusion 211 and the other is mounted on the friction strip mounting base 22.

[0043] Specifically, the base 11 is a rigid metal part. The end wall 112 serves as a shield. The side wall 113 provides a machining reference for the steps. The drive component mounting slot has two steps 114 machined in total, and the steps 114 serve as the mounting reference for the fixed guide 31.

[0044] Before installation, the elastic element 41, the first piezoelectric ceramic 42, the second piezoelectric ceramic 43, the third piezoelectric ceramic 44, the first friction plate 45 and the second friction plate 46 are assembled with the elastic element mounting plate 12 to form a friction plate module, and the friction strip 47 is assembled with the friction strip mounting base 22 to form a friction strip module.

[0045] The installation process of the piezoelectric drive motor mentioned above includes the following steps: First, the fixed guide member 31 is connected to the step 114 of the base 11 by the fixed guide member fixing screw 33. In the figure, the fixed guide member 31 on the left is first fixedly connected to the base 11, while the fixed guide member 31 on the right is not completely fixed to the base 11. Then, the elastic element 41, the first piezoelectric ceramic 42, the second piezoelectric ceramic 43, the third piezoelectric ceramic 44, the first friction plate 45 and the second friction plate 46 are first fixed to the elastic element mounting plate 12 and then fixed to the bottom of the groove 111. Subsequently, the displacement platform 21, along with the friction strip mounting base 22 and the motion guide 32 that are not fully fixedly connected, is installed between the two fixed guides 31; Then, adjust the right fixed guide 31 to be parallel to the guide rail by adjusting the guide rail adjustment end 34 on the right side of the base 11. After that, tighten the motion guide fixing screw 35 of the motion guide 32 and the fixing guide fixing screw 33 of the right fixed guide 31. Then, by adjusting the positions of the friction strip mounting seats 22 on both sides of the base 11 through the friction strip mounting seat adjustment ends 23, the friction strip mounting seats 22 on both sides are adjusted to generate appropriate friction force at the friction pair, and the friction strip mounting seat fixing screws 24 of the friction strip mounting seats 22 are tightened. Finally, remove the adjustment tool from the guide rail adjustment end 34 to complete the assembly.

[0046] The above technical solutions enable the assembly of piezoelectric drive motors, the precise installation of guide components, and the adjustment of internal friction force in friction pairs.

[0047] In this embodiment, the inchworm-type piezoelectric drive motor further includes a detection component, which includes a grating ruler 51 and a grating data reading device 52. The grating ruler 51 is fixed relative to the displacement platform component 2, and the grating data reading device 52 is fixed on the base component 1.

[0048] Specifically, the grating ruler 51 is rigidly connected to the displacement platform assembly 2 and moves synchronously with the displacement platform assembly 2 along the x-axis, serving as the motion detection end; the grating data reading device 52 is rigidly connected to the base assembly 1 and serves as the fixed detection end, with the reading head facing the detection surface of the grating ruler, reading the grating signal in a non-contact manner.

[0049] Through the above technical solution, the grating ruler and the grating data reading device work together to realize the closed-loop motion of the piezoelectric drive motor, which has high positioning accuracy.

[0050] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A inchworm-type piezoelectric drive motor, characterized in that, include: Base assembly; A displacement platform assembly is located on one side of the base assembly along the z-axis direction; A guide rail assembly is connected between the base assembly and the displacement platform assembly, and is used to guide the displacement platform assembly to translate relative to the base assembly along the x-axis direction, wherein the x-axis direction is perpendicular to the z-axis direction; A driving assembly, disposed between the base assembly and the displacement platform assembly, includes an elastic element, a first piezoelectric ceramic, a second piezoelectric ceramic, a third piezoelectric ceramic, a first friction plate, a second friction plate, and a friction strip. The elastic element is mounted on the base assembly. The first, second, and third piezoelectric ceramics are sequentially mounted on the elastic element along the x-axis. The first and third piezoelectric ceramics can extend and retract along the x-axis, and the second piezoelectric ceramic can extend and retract along the y-axis. The y-axis is perpendicular to both the z-axis and the x-axis. The first friction plate is disposed on the first piezoelectric ceramic along the x-axis. The second friction plate is located on the side of the third piezoelectric ceramic along the y-axis direction; the friction strip is mounted on the displacement platform assembly and located on the side of the elastic element along the y-axis direction, and the friction strip extends along the x-axis direction. When the first piezoelectric ceramic is de-energized, the first friction plate contacts the friction strip and maintains a certain frictional force. When the first piezoelectric ceramic is energized and elongates, the first friction plate disengages from the friction strip. When the third piezoelectric ceramic is de-energized, the second friction plate contacts the friction strip and maintains a certain frictional force. When the third piezoelectric ceramic is energized and elongates, the second friction plate disengages from the friction strip.

2. The inchworm-type piezoelectric drive motor according to claim 1, characterized in that, Each of the driving components includes two friction strips, two first friction plates, and two second friction plates. The two friction strips are symmetrically arranged on both sides of the elastic element along the y-axis. The two first friction plates are respectively arranged on both sides of the first piezoelectric ceramic along the y-axis and respectively cooperate with the two friction strips. The two second friction plates are respectively arranged on both sides of the third piezoelectric ceramic along the y-axis and respectively cooperate with the two friction strips.

3. The inchworm-type piezoelectric drive motor according to claim 1, characterized in that, The inchworm-type piezoelectric drive motor includes two drive components arranged at intervals along the y-axis.

4. The inchworm-type piezoelectric drive motor according to claim 1, characterized in that, The elastic element is provided with a first ceramic mounting groove, a second ceramic mounting groove and a third ceramic mounting groove arranged sequentially along the x-axis direction, and the first piezoelectric ceramic, the second piezoelectric ceramic and the third piezoelectric ceramic are respectively disposed in the first ceramic mounting groove, the second ceramic mounting groove and the third ceramic mounting groove.

5. The inchworm-type piezoelectric drive motor according to claim 1, characterized in that, The base assembly includes a base and an elastic element mounting plate. The base is provided with a drive component mounting groove. The drive component mounting groove has a bottom in the z-axis direction, two end walls in the x-axis direction, and two side walls in the y-axis direction. The height of the end walls protruding from the bottom of the groove is lower than the height of the side walls protruding from the bottom of the groove. A step is provided at the end of the side wall away from the bottom of the groove. The elastic element mounting plate is fixed to one end of the bottom of the groove. The guide rail assembly includes two fixed guide members and two moving guide members. The two fixed guide members are respectively installed on the steps of the two side walls. At least one fixed guide member is installed on the step in an adjustable position along the y-axis direction. The two moving guide members are installed on the displacement platform assembly and cooperate with the two fixed guide members respectively. The drive assembly is located between the elastic element mounting plate and the bottom of the groove, and the elastic element is mounted on the elastic element mounting plate.

6. The inchworm-type piezoelectric drive motor according to claim 1, characterized in that, The displacement platform assembly includes a displacement platform and a friction strip mounting base. The friction strip mounting base is connected to the side of the displacement platform near the base assembly along the z-axis direction, and the position of the friction strip mounting base along the y-axis direction is adjustable to the displacement platform. The same drive assembly includes two friction strips, and at least one friction strip of the same drive assembly is fixed to the friction strip mounting base.

7. The inchworm-type piezoelectric drive motor according to claim 6, characterized in that, The displacement platform has a protrusion on the side of the base assembly along the z-axis direction; Of the two friction strips in the same drive assembly, one is mounted on the protrusion and the other is mounted on the friction strip mounting base.

8. The inchworm-type piezoelectric drive motor according to claim 1, characterized in that, The inchworm-type piezoelectric drive motor also includes a detection component, which includes a grating ruler and a grating data reading device. The grating ruler is fixed relative to the displacement platform component, and the grating data reading device is fixed on the base component.

9. A control method for controlling the inchworm-type piezoelectric drive motor according to any one of claims 1 to 8, characterized in that, Includes the following steps: S11. The first piezoelectric ceramic, the second piezoelectric ceramic, and the third piezoelectric ceramic are all de-energized. The first friction plate is in contact with the friction strip and maintains a certain friction force. The second friction plate is in contact with the friction strip and maintains a certain friction force. S12. Control the first piezoelectric ceramic to extend when energized, and the first friction piece disengages from the friction strip; S13. Control the second piezoelectric ceramic to extend when energized, causing the second friction plate to move away from the first friction plate along the x-axis, thereby driving the displacement platform assembly to move forward through the friction strip; S14. Control the first piezoelectric ceramic to de-energize and shorten, and the first friction piece contacts the friction strip and maintains a certain friction force; S15. Control the third piezoelectric ceramic to extend when energized, and the second friction piece disengages from the friction strip; S16. Control the second piezoelectric ceramic to de-energize and shorten, causing the first friction plate to move along the x-axis towards the second friction plate, thereby driving the displacement platform assembly to move forward through the friction strip; S17. Control the third piezoelectric ceramic to de-energize and shorten, end the control or return to step S12.

10. A control method for controlling the inchworm-type piezoelectric drive motor according to any one of claims 1 to 8, characterized in that, The control method includes the following steps: S21. The first piezoelectric ceramic, the second piezoelectric ceramic, and the third piezoelectric ceramic are all de-energized. The first friction plate is in contact with the friction strip and maintains a certain friction force. The second friction plate is in contact with the friction strip and maintains a certain friction force. S22. Control the third piezoelectric ceramic to extend when energized, and the second friction piece disengages from the friction strip; S23. Control the second piezoelectric ceramic to extend when energized, causing the first friction piece to move away from the second friction piece along the x-axis, and then drive the displacement platform assembly to move in the opposite direction through the friction strip; S24. The third piezoelectric ceramic is de-energized and shortened, and the second friction plate contacts the friction strip and maintains a certain frictional force. S25. Control the first piezoelectric ceramic to extend when energized, and the first friction piece disengages from the friction strip; S26. Control the second piezoelectric ceramic to de-energize and shorten, causing the second friction plate to move along the x-axis towards the first friction plate, and then drive the displacement platform assembly to move in the opposite direction through the friction strip; S27. Control the first piezoelectric ceramic to de-energize and shorten, end the control or return to step S22.

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