Piezoelectric Actuator

Abstract

The present invention relates to the field of micro-drive technology, and discloses a piezoelectric actuator. The piezoelectric actuator includes a fixed end, an actuating end, a piezoelectric assembly, a secondary moving part, a pre-compression magnet, and a decompression assembly. The piezoelectric assembly can drive the secondary moving part to move at the fixed end to move the actuating end; the pre-compression magnet is arranged on the secondary moving part, and has a magnetic force with the fixed end, so that the secondary moving part is pressed at the fixed end with a preset pressure; the decompression assembly includes a decompression magnet and a decompression coil, and the decompression coil is energized to have a magnetic field with the same or opposite magnetic properties as the decompression magnet to adsorb or repel the fixed end, so that the fixed end is stationary relative to the actuating end or the fixed end can move relative to the actuating end; or the decompression coil can change the direction of the current to have a magnetic field with the same or opposite magnetic properties as the decompression magnet. The present invention facilitates increasing the upper limit of the holding force between the piezoelectric element and the friction surface when the piezoelectric assembly is not energized; at the same time, it makes the movement of the secondary moving part more stable; and it also has an additional braking function.

Description

Technical Field

[0001] The present invention relates to the field of micro-driving technology, and in particular to a piezoelectric actuator. Background Art

[0002] Piezoelectric actuators are components that use the reverse piezoelectric effect to generate displacement by applying voltage, and can provide an alternative to familiar electromagnetic devices such as motors and solenoids. They have advantages such as higher reliability, lower power consumption, smaller size, and higher position resolution. Since piezoelectric actuators are driven by friction, they have a holding force when not powered. However, this holding force is affected by the pre-pressure of the piezoelectric actuator, the material properties of the friction surface and piezoelectric material, the geometric design of the piezoelectric actuator, etc. Therefore, there are limitations on the design of the holding force of the piezoelectric actuator.

[0003] Therefore, there is an urgent need for a piezoelectric actuator to solve the above problems. Summary of the invention

[0004] Based on the above, an object of the present invention is to provide a piezoelectric actuator, which has a good degree of freedom in designing the holding force, a more stable movement of the secondary mover, and an additional braking function.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] Piezoelectric actuators, including:

[0007] A fixed end, an actuating end, a piezoelectric component and a secondary moving member, wherein the piezoelectric component can drive the secondary moving member to move at the fixed end to move the actuating end;

[0008] A pre-pressing magnet is disposed on the secondary moving member and has a magnetic force with the fixed end so that the secondary moving member is pressed against the fixed end with a preset pressure;

[0009] A decompression component includes a decompression magnet and a decompression coil, wherein the decompression coil can be energized to have a magnetic field with the same or opposite magnetic properties as the decompression magnet to attract or repel the fixed end so that the fixed end is stationary relative to the actuating end or the actuating end can move relative to the fixed end; or the decompression coil can change the direction of current to have a magnetic field with the same or opposite magnetic properties as the decompression magnet.

[0010] As a preferred solution of the piezoelectric actuator, the decompression magnet is arranged on the secondary moving part, and the decompression magnet can move in a direction approaching and away from the fixed end.

[0011] As a preferred solution of the piezoelectric actuator, a mounting groove is provided on a side of the secondary moving member close to the fixed end, and the decompression magnet is slidably disposed in the mounting groove.

[0012] As a preferred solution of the piezoelectric actuator, two blocks are arranged at intervals on one side of the secondary movable member close to the fixed end along the moving direction of the secondary movable member, the decompression magnet is arranged in the block, and the decompression coil is wound on the outside of the two blocks.

[0013] As a preferred solution of the piezoelectric actuator, the fixed end is provided with a matching block, the matching block is arranged toward the decompression magnet, and can be attracted to or repelled by the decompression magnet.

[0014] As a preferred solution of the piezoelectric actuator, the decompression coil is wound around the matching block.

[0015] As a preferred solution of the piezoelectric actuator, the decompression magnet is arranged at the actuating end and can move in a direction approaching and away from the fixed end, and the decompression coil is arranged at the fixed end.

[0016] As a preferred solution of the piezoelectric actuator, the decompression magnet is configured as a cylinder, a cube or a cuboid.

[0017] As a preferred solution of the piezoelectric actuator, the pre-stressing magnet is configured as an electromagnet, and the magnitude of the magnetic force is adjustable.

[0018] As a preferred solution of the piezoelectric actuator, the piezoelectric actuator also includes a commutator, the piezoelectric component can drive the secondary moving member to move in a first direction relative to the fixed end, and the commutator can make the actuating end move in a second direction relative to the fixed end, and the second direction is set at an angle to the first direction.

[0019] The beneficial effects of the present invention are:

[0020] The present invention arranges a pre-stressing magnet on the secondary moving part, and arranges the fixed end to be a magnetic material for magnetic attraction with the pre-stressing magnet, so that the secondary moving part can be pressed on the fixed end with a preset pressure, which is convenient for increasing the upper limit of the holding force between the piezoelectric element and the friction surface when the piezoelectric component is not energized, so as to improve the design freedom of the piezoelectric actuator; at the same time, the movement of the secondary moving part is made more stable. In addition, the piezoelectric actuator is also provided with a decompression component, which can achieve a change in the holding force, or achieve braking or releasing the brake between the actuating end and the fixed end by changing the magnitude or direction of the magnetic force between the decompression coil and the decompression magnet. Specifically, when the magnetic field of the decompression coil is in the same direction as the decompression magnet, there is an attraction between the decompression magnet and the fixed end, which can increase the upper limit of the preset pressure; when the magnetic field of the decompression coil is in the opposite direction to the decompression magnet, there is a repulsive force between the decompression magnet and the fixed end, that is, the brake is released, and the actuating end can move relative to the fixed end. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0022] Figure 1 is a schematic diagram of a piezoelectric actuator provided in a specific embodiment of the present invention;

[0023] Figure 2 is a partial schematic diagram of an implementation of a piezoelectric actuator provided in a specific embodiment of the present invention;

[0024] Figure 3 is a partial diagram of another implementation of a piezoelectric actuator provided in a specific embodiment of the present invention;

[0025] Figure 4 is a schematic diagram of a plurality of piezoelectric actuators provided in a specific embodiment of the present invention applied to a lens;

[0026] Figure 5 is a schematic diagram of a plurality of piezoelectric actuators provided by a specific embodiment of the present invention being applied to a display module;

[0027] Figure 6 is a schematic diagram of a plurality of piezoelectric actuators provided in a specific embodiment of the present invention applied to a lens;

[0028] Figure 7 is a schematic diagram of a piezoelectric actuator with a hidden secondary moving part provided in a specific embodiment of the present invention;

[0029] Figure 8 is a schematic diagram of a piezoelectric actuator with a hidden fixed end and a decompression magnet provided in a specific embodiment of the present invention;

[0030] Fig. 9 is a schematic diagram of another piezoelectric actuator with a hidden secondary moving member provided in a specific embodiment of the present invention;

[0031] Fig.10 is a schematic diagram of another piezoelectric actuator with a hidden fixed end and a decompression magnet provided by a specific embodiment of the present invention;

[0032] Fig.11 is a schematic diagram of another piezoelectric actuator with a hidden fixed end provided in a specific embodiment of the present invention;

[0033] Fig.12 is a schematic diagram of another piezoelectric actuator provided in a specific embodiment of the present invention;

[0034] Fig.13 It is a partial schematic diagram of a piezoelectric actuator using a sliding commutator provided in a specific embodiment of the present invention.

[0035] In the figure:

[0036] 100, fixed end; 110, matching block; 120, guide rod;

[0037] 200, actuating end;

[0038] 300, piezoelectric component;

[0039] 400, secondary moving member; 410, first guide surface; 411, first avoidance groove; 420, first guide groove; 430, second guide groove; 440, mounting groove; 450, stopper;

[0040] 500, pre-pressed magnet;

[0041] 600, decompression assembly; 610, decompression magnet; 620, decompression coil;

[0042] 700, reversing member; 710, first reversing wheel; 720, second reversing wheel; 730, reversing shaft; 740, reversing block;

[0043] 800, guide rail; 810, second guide surface; 811, third guide groove; 812, second avoidance groove; 820, first avoidance notch; 830, guide protrusion; 840, second avoidance notch;

[0044] 910, display module; 920, camera lens; 930, lens; 940, mounting lug. DETAILED DESCRIPTION

[0045] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0046] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0047] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0049] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0050] like Figure 1-Figure 7 As shown, this embodiment provides a piezoelectric actuator, which includes a fixed end 100, an actuating end 200, a piezoelectric component 300, a secondary moving part 400, a pre-pressing magnet 500 and a decompression component 600. The piezoelectric component 300 can drive the secondary moving part 400 to move at the fixed end 100 to move the actuating end 200; the pre-pressing magnet 500 is arranged on the secondary moving part 400 and has a magnetic force with the fixed end 100, so that the secondary moving part 400 is pressed at a preset pressure. The fixed end 100; the decompression component 600 includes a decompression magnet 610 and a decompression coil 620, and the decompression coil 620 can be energized to have a magnetic field with the same or opposite magnetic properties as the decompression magnet 610 to attract or repel the fixed end 100, so that the fixed end 100 is stationary relative to the actuating end 200 or the fixed end 100 can move relative to the actuating end 200; or the decompression coil 620 can change the direction of the current to have a magnetic field with the same or opposite magnetic properties as the decompression magnet 610.

[0051] By setting a pre-compression magnet 500 on the secondary moving part 400 and setting the fixed end 100 to a magnetic material for magnetic attraction with the pre-compression magnet 500, the secondary moving part 400 can be pressed on the fixed end 100 with a preset pressure, which is convenient for increasing the upper limit of the holding force between the piezoelectric element and the friction surface when the piezoelectric component 300 is not powered, so as to improve the design freedom of the piezoelectric actuator; at the same time, the movement of the secondary moving part 400 is more stable. In addition, the piezoelectric actuator is also provided with a decompression component 600, which can change the holding force or realize braking or releasing the brake between the actuating end 200 and the fixed end 100 by changing the magnitude or direction of the magnetic force between the decompression coil 620 and the decompression magnet 610. Specifically, when the magnetic field of the decompression coil 620 is in the same direction as the decompression magnet 610, there is an attractive force between the decompression magnet 610 and the fixed end 100, which can increase the upper limit of the preset pressure; when the magnetic field of the decompression coil 620 is in the opposite direction to the decompression magnet 610, there is a repulsive force between the decompression magnet 610 and the fixed end 100, that is, the brake is released, and the actuating end 200 can move relative to the fixed end 100.

[0052] In this embodiment, Figure 7-Figure 12 As shown, in order to achieve the installation of the decompression component 600, the decompression magnet 610 is set on the secondary movable part 400, and the decompression magnet 610 can move in the direction close to and away from the fixed end 100, so that the decompression magnet 610 can approach and adsorb the fixed end 100, or repel and move away from the fixed end 100 when the decompression coil 620 is powered on and off.

[0053] Specifically, Figure 7 and Figure 8 As shown, a mounting groove 440 is provided on one side of the secondary moving part 400 close to the fixed end 100, and the decompression magnet 610 is slidably arranged in the mounting groove 440. It can be understood that the shape of the mounting groove 440 is adapted to the decompression magnet 610 to limit the movement of the decompression magnet 610 along the plane in which the secondary moving part 400 and the fixed end 100 move relative to each other. Optionally, the decompression magnet 610 is configured as a cylinder, a cube or a cuboid. Accordingly, the cross-section of the mounting groove 440 is configured as a circle, a square or a rectangle. It is worth noting that the decompression coil 620 can be wound into different shapes, such as a square, a rectangle or a runway shape in cross-section. On the one hand, it is used to adapt to the shape of the decompression magnet 610, and on the other hand, it can be configured with a more desired magnetic force size, which is not specifically limited here.

[0054] In other embodiments, to simplify the structure of the mounting slot 440, as shown in FIG. Fig. 9 and Fig.10As shown, two stoppers 450 are arranged at intervals on one side of the secondary moving member 400 close to the fixed end 100 along the moving direction of the secondary moving member 400, the decompression magnet 610 is arranged in the stopper 450, and the decompression coil 620 is wound outside the two stoppers 450. By setting the two stoppers 450, the decompression magnet 610 cannot move with the secondary moving member 400 relative to the fixed end 100, and while ensuring the installation of the decompression magnet 610, the decompression coil 620 can also be wound outside the two stoppers 450, further simplifying the structure of the piezoelectric actuator.

[0055] Alternatively, if Fig.11 As shown, a matching block 110 may also be provided at the fixed end 100, the matching block 110 is provided toward the decompression magnet 610, and can be attracted or repelled by the decompression magnet 610. By providing the matching block 110 to replace the fixed end 100 and cooperate with the decompression magnet 610, on the one hand, it is convenient to replace the matching block 110 separately after wear; on the other hand, the decompression coil 620 may also be wound around the matching block 110, so as to realize the installation of the decompression coil 620 at the same time.

[0056] Preferably, the pre-compression magnet 500 is configured as an electromagnet, and the magnetic force is adjustable. The magnetic force of the electromagnet has a wider adjustment range, which can further increase the upper limit of the holding force between the piezoelectric element and the friction surface when the piezoelectric assembly 300 is not powered.

[0057] As an alternative to piezoelectric actuators, Fig.12 As shown, the decompression magnet 610 is disposed at the actuating end 200 and can move in the direction close to and away from the fixed end 100, and the decompression coil 620 is disposed at the fixed end 100. The decompression magnet 610 and the decompression coil 620 act on the actuating end 200, and the piezoelectric actuator is braked by driving the actuator to be fixed relative to the fixed end 100.

[0058] In other embodiments, Figure 1-Figure 3 As shown, the piezoelectric actuator further includes a commutator 700, and the piezoelectric component 300 can drive the secondary moving part 400 to move relative to the fixed end 100 along a first direction, and the commutator 700 can enable the actuating end 200 to move relative to the fixed end 100 along a second direction, and the second direction is set at an angle to the first direction. Through the commutation of the commutator 700, the piezoelectric component 300 can drive the secondary moving part 400 to move relative to the fixed end 100 along the first direction, while the actuating end 200 can move relative to the fixed end 100 along the second direction, that is, the displacement of the actuating end 200 along the second direction is converted into the displacement of the secondary moving part 400 along the first direction, thereby reducing the size of the secondary moving part 400 in the second direction and no need to reserve active space in the second direction, effectively reducing the size of the piezoelectric actuator and increasing the use scenarios of the piezoelectric actuator.

[0059] Furthermore, the fixed end 100 of the piezoelectric actuator is also provided with a guide rail 800, a second guide surface 810 is provided on the guide rail 800, the secondary moving part 400 is provided with a first guide surface 410, the actuating end 200 is arranged on the reversing shaft 730 of the reversing part 700, and the reversing shaft 730 is coaxially sleeved with a first reversing wheel 710 and a second reversing wheel 720, wherein the first reversing wheel 710 is used to cooperate with the first guide surface 410, and the second reversing wheel 720 is used to cooperate with the second guide surface 810. When the secondary moving part 400 moves relative to the fixed end 100, the first guide surface 410 drives the first reversing wheel 710 to roll. Since the second guide surface 810 extends along the second direction, the second reversing wheel 720 moves along the second direction on the guide rail 800, thereby driving the actuating end 200 to move along the second direction relative to the fixed end 100. That is, the actuating end 200 and the secondary moving member 400 can move in different directions by coaxially setting the first reversing wheel 710 and the second reversing wheel 720 in cooperation with the first guide surface 410 and the second guide surface 810 .

[0060] like Figure 1 and Figure 2 As shown, the reversing member 700 includes a reversing shaft 730 and a first reversing wheel 710 and a second reversing wheel 720 coaxially sleeved on the reversing shaft 730. The actuating end 200 is arranged on the reversing shaft 730. The first reversing wheel 710 can roll along the first guide surface 410, and the second reversing wheel 720 can roll along the second guide surface 810, so that the reversing member 700 moves along the second direction, and the second direction is arranged at an angle to the first direction.

[0061] By setting the first reversing wheel 710 and the second reversing wheel 720 coaxially sleeved on the reversing shaft 730, wherein the first reversing wheel 710 is used to cooperate with the first guide surface 410, and the second reversing wheel 720 is used to cooperate with the second guide surface 810, when the secondary moving part 400 moves relative to the fixed end 100, the first guide surface 410 drives the first reversing wheel 710 to roll, and since the second guide surface 810 extends along the second direction, the second reversing wheel 720 moves along the second direction on the guide rail 800, thereby driving the actuating end 200 to move along the second direction relative to the fixed end 100. That is, by coaxially setting the first reversing wheel 710 and the second reversing wheel 720, in cooperation with the first guide surface 410 and the second guide surface 810, the actuating end 200 and the secondary moving part 400 can move in different directions.

[0062] In this embodiment, the first direction is Figure 1 The X direction is shown in Figure 1 The Y direction is shown in , and the X direction and the Y direction are arranged vertically.

[0063] Furthermore, a first guide groove 420 is provided at one end of the secondary movable member 400 close to the reversing member 700, and the groove top of the first guide groove 420 forms a first guide surface 410. When the secondary movable member 400 moves, the first reversing wheel 710 cooperates with the groove top of the first guide groove 420. Since the diameter of the first reversing wheel 710 is smaller than the diameter of the second reversing wheel 720, and the groove depth of the first guide groove 420 is greater than the radius difference between the first reversing wheel 710 and the second reversing wheel 720, the second reversing wheel 720 and the groove bottom of the first guide groove 420 are spaced apart, so there will be no interference between the two, and further, it will not affect the cooperation between the second reversing wheel 720 and the second guide surface 810 of the guide rail 800.

[0064] Preferably, two first reversing wheels 710 are provided, and the second reversing wheel 720 is provided between the two first reversing wheels 710. The two first reversing wheels 710 respectively roll with the groove tops on both sides of the first guide groove 420, and the second reversing wheel 720 is placed in the first guide groove 420 and is spaced apart from the groove bottom of the first guide groove 420. By providing two first reversing wheels 710, the force on the reversing member 700 is more balanced, thereby making the cooperation between the reversing member 700 and the secondary moving member 400 more stable. At the same time, the provision of the first guide groove 420 can also effectively prevent the second reversing wheel 720 from slipping out of the first guide groove 420, making the cooperation between the reversing member 700 and the secondary moving member 400 more reliable.

[0065] In this embodiment, the first reversing wheel 710 and the second reversing wheel 720 can be sleeved on the reversing shaft 730 through a bearing, or the outer ring of the bearing can be used as the first reversing wheel 710 or the second reversing wheel 720. In other embodiments, the axial length of the first reversing wheel 710 can be set to be greater than the axial length of the second reversing wheel 720, and the second reversing wheel 720 can be rotatably arranged outside the first reversing wheel 710, and the rolling fit between the first reversing wheel 710 and the first guide surface 410 and the second reversing wheel 720 and the second guide surface 810 can also be achieved.

[0066] As an optional solution of the piezoelectric actuator, in order to realize that the switching member 700 cooperates with the first guide surface 410 and the second guide surface 810 at the same time, as shown in FIG. Figure 3As shown, a second guide groove 430 is provided at one end of the secondary moving member 400 close to the diverting member 700, the diameter of the first diverting wheel 710 is larger than the diameter of the second diverting wheel 720, the groove bottom of the second guide groove 430 forms the first guide surface 410, and the groove depth of the second guide groove 430 is smaller than the radius difference between the first diverting wheel 710 and the second diverting wheel 720. With such a configuration, when the secondary moving member 400 moves, the first diverting wheel 710 cooperates with the groove bottom of the second guide groove 430, and since the groove depth of the second guide groove 430 is smaller than the radius difference between the first diverting wheel 710 and the second diverting wheel 720, the groove top of the second guide groove 430 will not interfere with the second diverting wheel 720, and thus will not affect the rolling cooperation between the second diverting wheel 720 and the second guide surface 810 of the guide rail 800.

[0067] Furthermore, two second diverting wheels 720 are provided, and the first diverting wheel 710 is provided between the two second diverting wheels 720 . The two second diverting wheels 720 can improve the stability of the cooperation between the diverting member 700 and the guide rail 800 .

[0068] Preferably, the second guide surface 810 is provided with a third guide groove 811, the third guide groove 811 extends along the second direction, and the groove depth of the third guide groove 811 is greater than the radius difference between the first reversing wheel 710 and the second reversing wheel 720, so as to avoid interference between the groove bottom of the third guide groove 811 and the first reversing wheel 710, and ensure that the second reversing wheel 720 and the second guide surface 810 can roll together.

[0069] Exemplarily, the first guide surface 410 is set at an angle of 30° to 60° with the first direction. Optionally, the first guide surface 410 is set at an angle of 45° with the first direction. In other embodiments, those skilled in the art may set the angle between the first guide surface 410 and the first direction according to actual usage scenarios, which is not specifically limited here.

[0070] Preferably, if Figure 1 As shown, the fixed end 100 is provided with a guide rod 120, the guide rod 120 extends along a first direction, and the secondary moving member 400 can slide along the guide rod 120. By providing the guide rod 120, the moving direction of the secondary moving member relative to the fixed end 100 can be limited.

[0071] In this embodiment, in order to improve the reliability of the guide rod 120 in limiting the secondary moving member 400, a guide groove extending along the first direction is further provided on the secondary moving member 400, and the guide rod 120 is placed in the guide groove.

[0072] Specifically, Figure 4-Figure 6As shown, the actuation end 200 is connected to the optical lens module or display module 910, that is, the piezoelectric actuator can be used to actuate the optical lens module or display module 910 along its axis. Optionally, the optical lens module can be a lens 920, a lens 930, etc., so as to change its focal length.

[0073] Furthermore, the optical lens module or display module 910 is provided with a plurality of mounting lugs 940 in the circumference, and the actuating ends 200 of the plurality of piezoelectric actuators are connected one by one to the mounting lugs 940. By providing a plurality of piezoelectric actuators, the driving of the optical lens module or display module 910 is made more stable and reliable.

[0074] It is worth noting that the lens 920 is evenly and flexibly provided with six piezoelectric actuators at intervals in the circumference. When two of the piezoelectric actuators are used as the rotation axis, the rotation of the lens 920 can be achieved by driving the other four piezoelectric actuators to move respectively. It can be understood that during rotation, the piezoelectric actuators on both sides of the rotation axis move in opposite directions, that is, the actuating ends 200 of the two piezoelectric actuators on one side of the rotation axis move upward, and the actuating ends 200 of the two piezoelectric actuators on the other side of the rotation axis move downward.

[0075] In other embodiments, Fig.13 As shown, the rolling first reversing wheel 710 and the second reversing wheel 720 may be eliminated, and the reversing member 700 may be configured to slide with the first guide surface 410 and the second guide surface 810. That is, the reversing member 700 slides with the first guide surface 410 and the second guide surface 810 at the same time, so that the actuating end 200 and the secondary moving member 400 can move in different directions.

[0076] Preferably, the first guide surface 410 and / or the second guide surface 810 is provided with a lubricating layer. By providing a lubricating layer on the surface of the first guide surface 410 and the second guide surface 810 that slide in cooperation with the guide member, the friction between the first guide surface 410 and the second guide surface 810 and the switching member 700 can be reduced, making the switching process smoother, thereby ensuring that the actuation process of the piezoelectric actuator is smoother.

[0077] As an optional solution of the piezoelectric actuator, a first avoidance notch 820 is provided at one end of the guide rail 800, so that when the secondary movable member 400 moves close to the guide rail 800, the end of the secondary movable member 400 close to the guide rail 800 can be placed in the first avoidance notch 820, effectively avoiding collision between the secondary movable member 400 and the guide rail 800.

[0078] Specifically, a first avoidance groove 411 is provided on the first guide surface 410 , and the first avoidance groove 411 is provided to reduce the contact area between the first guide surface 410 and the switching member 700 , thereby reducing the friction between the switching member 700 and the first guide surface 410 .

[0079] Furthermore, a guide protrusion 830 is also provided at the first avoidance notch 820, and the guide protrusion 830 can be placed in the first avoidance groove 411. By providing the guide protrusion 830 that can cooperate with the first avoidance groove 411, while avoiding the interference between the guide rail 800 and the first guide surface 410, the sliding length of the reversing member 700 on the second guide surface 810 can be extended, thereby increasing the actuation distance.

[0080] Preferably, a second avoidance notch 840 is provided on the guide protrusion 830. By providing the second avoidance notch 840, when the secondary moving member 400 moves close to the guide rail 800, the bottom of the first avoidance groove 411 can be placed in the second avoidance notch 840, effectively avoiding the guide protrusion 830 from colliding with the first avoidance groove 411.

[0081] It is worth mentioning that in the scheme of setting the first reversing wheel 710 and the second reversing wheel 720, the setting of the first avoidance notch 820, the guide protrusion 830 and the second avoidance notch 840 can also achieve avoidance of the first guide groove 420, reduce the interference between the secondary moving part 400 and the guide rail 800 when moving, and ensure that the actuation process of the piezoelectric actuator is smoother and more reliable.

[0082] In this embodiment, a second avoidance groove 812 is further provided on the second guide surface 810 for reducing the contact area between the second guide surface 810 and the switching member 700 , thereby reducing the friction between the switching member 700 and the second guide surface 810 .

[0083] As an optional solution of the piezoelectric actuator, the commutator 700 includes a commutator shaft 730 and a commutator block 740 coaxially sleeved on the commutator shaft 730, wherein the actuating end 200 is disposed on the commutator shaft 730, and the commutator block 740 is used for sliding connection with the first guide surface 410 and the second guide surface 810. By disposing the commutator 700 in a split manner, it is convenient to replace the commutator block 740 after it is worn, which is conducive to extending the service life of the piezoelectric actuator.

[0084] Optionally, the commutation block 740 is provided in a hollow cylindrical shape, the interior of the hollow cylindrical shape is used to be connected to the commutation shaft 730, and the exterior is used to be slidably connected to the first guide surface 410 and the second guide surface 810. It can be understood that the outer wall of the hollow cylindrical shape is in line contact with the first guide surface 410 and the second guide surface 810, and the friction force is smaller than that of surface contact, thereby making the movement of the commutation member 700 smoother.

[0085] Preferably, a lubricating layer is provided on the outer wall of the commutation block 740. By providing a lubricating layer on the outer wall of the commutation block 740 that cooperates with the first guide surface 410 and the second guide surface 810, the friction between the commutation block 740 and the first guide surface 410 and the second guide surface 810 can be reduced, making the commutation process smoother, thereby ensuring that the actuation process of the piezoelectric actuator is smoother.

[0086] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The content of this specification should not be understood as limiting the present invention.

Claims

1. A piezoelectric actuator, characterized in that include: A fixed end (100), an actuating end (200), a piezoelectric component (300) and a secondary moving member (400), wherein the piezoelectric component (300) can drive the secondary moving member (400) to move at the fixed end (100) so as to move the actuating end (200); A pre-pressing magnet (500) is arranged on the secondary moving member (400) and has a magnetic force with the fixed end (100), so that the secondary moving member (400) is pressed on the fixed end (100) with a preset pressure; A decompression component (600), the decompression component (600) is used to increase the upper limit of a preset pressure or release the brake, and comprises a decompression magnet (610) and a decompression coil (620), the decompression coil (620) can be energized to have a magnetic field with the same or opposite magnetic properties as the decompression magnet (610) to attract or repel the fixed end (100) so that the fixed end (100) is stationary relative to the actuating end (200) or the actuating end (200) can be moved relative to the fixed end (100); or the decompression coil (620) can change the direction of current to have a magnetic field with the same or opposite magnetic properties as the decompression magnet (610).

2. The piezoelectric actuator according to claim 1, characterized in that: The decompression magnet (610) is arranged on the secondary moving part (400), and the decompression magnet (610) can move in a direction approaching and away from the fixed end (100).

3. The piezoelectric actuator according to claim 2, characterized in that: A mounting groove (440) is provided on one side of the secondary moving part (400) close to the fixed end (100), and the decompression magnet (610) is slidably disposed in the mounting groove (440).

4. The piezoelectric actuator according to claim 2, characterized in that: Two stoppers (450) are arranged at intervals on one side of the secondary moving member (400) close to the fixed end (100) along the moving direction of the secondary moving member (400); the decompression magnet (610) is arranged inside the stoppers (450); and the decompression coil (620) is wound around the outsides of the two stoppers (450).

5. The piezoelectric actuator according to claim 2, characterized in that: The fixed end (100) is provided with a matching block (110), and the matching block (110) is arranged toward the decompression magnet (610) and can be attracted to or repelled by the decompression magnet (610).

6. The piezoelectric actuator according to claim 5, characterized in that: The decompression coil (620) is wound around the matching block (110).

7. The piezoelectric actuator according to claim 1, characterized in that: The decompression magnet (610) is arranged at the actuating end (200) and is movable in a direction approaching and moving away from the fixed end (100); and the decompression coil (620) is arranged at the fixed end (100).

8. The piezoelectric actuator according to claim 1, wherein: The decompression magnet (610) is configured as a cylinder, a cube or a cuboid.

9. The piezoelectric actuator according to claim 1, wherein: The pre-compression magnet (500) is configured as an electromagnet, and the magnitude of the magnetic force is adjustable.

10. The piezoelectric actuator according to any one of claims 1 to 9, characterized in that: The piezoelectric actuator also includes a commutator (700), the piezoelectric component (300) can drive the secondary moving member (400) to move along a first direction relative to the fixed end (100), and the commutator (700) can enable the actuating end (200) to move along a second direction relative to the fixed end (100), and the second direction is arranged at an angle to the first direction.

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