Piezoelectric stack actuating device

Abstract

The invention discloses a piezoelectric stack actuating device. The piezoelectric stack actuating device comprises a fixed seat, an amplifying mechanism, two piezoelectric stacks, two first connecting pieces and two pre-tightening bolts, the two piezoelectric stacks are arranged along a first direction, and the two first connecting pieces are arranged along the first direction; the first connecting piece comprises a first plane end and a first convex face end which are oppositely arranged in the second direction. The second direction is orthogonal to the first direction; the amplifying mechanism comprises two first grooves arranged in the first direction. The piezoelectric stack comprises a first end and a second end which are oppositely arranged along a second direction; the first end is connected with the fixed seat, the second end is connected with the first plane end, and the first convex surface end is connected with the first groove; the first connecting piece further comprises a first through hole penetrating through the first connecting piece in the third direction. The third direction is respectively orthogonal to the first direction and the second direction; in the actuated state, the voltage differences applied to the two piezoelectric stacks are different. The service life of the piezoelectric stack actuating device can be prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of piezoelectric stacks, and in particular to a piezoelectric stack actuating device. Background Art

[0002] As a new type of solid-state actuator, piezoelectric actuators have the advantages of high precision and fast response, and have become the first choice for performance improvement and replacement of high-precision drive components. Piezoelectric stack actuators are in line with the development trend of miniaturization and functional integration of cutting-edge equipment due to their unique advantages of low driving voltage and small structure size.

[0003] However, some existing high-precision piezoelectric stack actuators are susceptible to damage and have a short service life due to the repeated non-uniform deformation of the piezoelectric stack. Summary of the invention

[0004] The present invention provides a piezoelectric stack actuator device to solve the problems of easy damage and short service life of the existing piezoelectric stack actuator device, and at the same time has the characteristics of high repeatability.

[0005] An embodiment of the present invention provides a piezoelectric stack actuation device, comprising a fixing seat, an amplifying mechanism, two piezoelectric stacks, two first connecting members, and two pre-tightening bolts; the two piezoelectric stacks are arranged along a first direction, and the two first connecting members are arranged along the first direction;

[0006] The first connecting member comprises a first plane end and a first convex end which are arranged opposite to each other along a second direction; the second direction is orthogonal to the first direction;

[0007] The amplifying mechanism comprises two first grooves arranged along the first direction;

[0008] The piezoelectric stack includes a first end and a second end disposed opposite to each other along the second direction;

[0009] The first end is connected to the fixing seat, the second end is connected to the first plane end, and the first convex end is connected to the first groove;

[0010] The first connecting member further comprises a first through hole penetrating the first connecting member along a third direction; the third direction is orthogonal to the first direction and the second direction respectively;

[0011] The two pre-tightening bolts are arranged along the third direction; the fixing seat further comprises two second through holes arranged along the third direction and penetrating the fixing seat along the second direction; the amplifying mechanism further comprises two screw holes arranged along the third direction and penetrating the amplifying mechanism along the second direction; the pre-tightening bolt passes through the second through hole and the screw hole;

[0012] In the actuated state, the voltage differences applied to the two piezoelectric stacks are different.

[0013] Optionally, the first connecting member includes a first sub-section, a second sub-section and a third sub-section arranged along the second direction;

[0014] The first sub-section includes a first sub-plane end and a second sub-plane end that are oppositely arranged along the second direction; the second sub-section includes a third sub-plane end and a fourth sub-plane end that are oppositely arranged along the second direction; the third sub-section includes a fifth sub-plane end and a first sub-convex surface end that are oppositely arranged along the second direction;

[0015] The first sub-plane end is connected to the second end, the second sub-plane end is connected to the third sub-plane end, the fourth sub-plane end is connected to the fifth sub-plane end, and the first sub-convex surface end is connected to the first groove;

[0016] The first through hole includes a first sub-through hole and a second sub-through hole arranged along the first direction; the first sub-through hole and the second sub-through hole both penetrate the second section along the third direction.

[0017] Optionally, the first groove includes a first concave curved surface extending along the third direction;

[0018] The first sub-convex surface end comprises a first sub-convex curved surface extending along the third direction;

[0019] The curvature radius of the first concave surface is greater than the curvature radius of the first sub-convex surface;

[0020] The first sub-convex surface is connected to the first concave surface through a first structural adhesive.

[0021] Optionally, the first sub-convex surface end includes a first sub-convex curved surface extending along the third direction;

[0022] The second subsection further includes a second sub-convex surface end and a third sub-convex surface end which are arranged opposite to each other along the first direction;

[0023] The second sub-convex surface end includes a second sub-convex curved surface extending along the third direction;

[0024] The third sub-convex surface end includes a third sub-convex curved surface extending along the third direction;

[0025] The first sub-convex surface is connected to the second sub-convex surface and the third sub-convex surface respectively.

[0026] Optionally, the piezoelectric stack actuator further comprises two second connecting members arranged along the first direction; the second connecting member comprises a second convex end and a second flat end arranged opposite to each other along the second direction;

[0027] The fixing seat comprises two second grooves arranged along the first direction;

[0028] The second convex end is connected to the second groove, and the second flat end is connected to the first end;

[0029] The second connecting member further includes a gap penetrating the second connecting member along the first direction.

[0030] Optionally, the second connecting member includes a fourth sub-section, a fifth sub-section and a sixth sub-section arranged along the second direction;

[0031] The fourth subsection includes a fourth sub-convex end and a sixth sub-plane end that are oppositely arranged along the second direction; the fifth subsection includes a seventh sub-plane end and an eighth sub-plane end that are oppositely arranged along the second direction; the sixth subsection includes a ninth sub-plane end and a tenth sub-plane end that are oppositely arranged along the second direction;

[0032] The fourth sub-convex surface end is connected to the second groove, the sixth sub-plane end is connected to the seventh sub-plane end, the eighth sub-plane end is connected to the ninth sub-plane end, and the tenth sub-plane end is connected to the first end;

[0033] The gap includes a first gap and a second gap; along the third direction, the first gap and the second gap are respectively located on two opposite sides of the fifth section.

[0034] Optionally, the second groove includes a second concave curved surface extending along the third direction;

[0035] The fourth sub-convex surface end includes a fourth sub-convex curved surface extending along the third direction;

[0036] The curvature radius of the second concave surface is greater than the curvature radius of the fourth sub-convex surface;

[0037] The fourth sub-convex surface is connected to the second concave surface through a second structural adhesive.

[0038] Optionally, the first through hole includes a round hole or an oblong hole;

[0039] The oblong hole comprises a first semicircular hole, a second semicircular hole and a rectangular hole, and the first semicircular hole and the second semicircular hole are respectively located on two opposite sides of the rectangular hole.

[0040] Further, the two piezoelectric stacks include a first piezoelectric stack and a second piezoelectric stack; the first piezoelectric stack includes a first cathode and a first anode; the second piezoelectric stack includes a second cathode and a second anode;

[0041] The first cathode is electrically connected to the second cathode; in a non-actuated state, the voltage applied to the first cathode is the same as the second cathode, and the voltage applied to the first anode is the same as the second anode; in the actuated state, the voltage applied to the first cathode is the same as the second cathode, and the voltage applied to the first anode is different from the voltage applied to the second anode;

[0042] Alternatively, the first anode is electrically connected to the second anode; in the non-actuated state, the voltage applied to the first anode and the second anode is the same, and the voltage applied to the first cathode and the second cathode is the same; in the actuated state, the voltage applied to the first anode and the second anode is the same, and the voltage applied to the first cathode and the second cathode is different.

[0043] The technical solution of the embodiment of the present invention, by providing a first through hole on the first connecting member connecting the piezoelectric stack and the amplifying mechanism, can make the first connecting member have a certain flexibility, which is beneficial to reduce the stress on the first connecting member when the piezoelectric stack actuator is in an actuated state, that is, when the amplifying mechanism moves relative to the piezoelectric stack, thereby solving the problem of easy damage and short service life of the existing piezoelectric stack actuator, and has the beneficial effect of increasing the service life of the piezoelectric stack actuator and increasing the repeatability accuracy.

[0044] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] 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. 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 these drawings without creative work.

[0046] Figure 1 A schematic structural diagram of a piezoelectric stack actuator provided by an embodiment of the present invention;

[0047] Figure 2 A three-dimensional assembly diagram of a piezoelectric stack actuator provided by an embodiment of the present invention;

[0048] Figure 3 A schematic structural diagram of a first connecting member provided in an embodiment of the present invention;

[0049] Figure 4 A schematic structural diagram of a second connecting member provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0050] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0051] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. The orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, and is only used to illustrate the relative positional relationship between the components or components, and does not particularly limit the specific installation orientation of the components or components.

[0052] Figure 1 A schematic diagram of the structure of a piezoelectric stack actuator provided in an embodiment of the present invention, Figure 2 A three-dimensional assembly diagram of a piezoelectric stack actuator provided by an embodiment of the present invention. Figure 1 and Figure 2The piezoelectric stack actuator in the embodiment of the present invention includes a fixed seat 10, an amplifying mechanism 20, two piezoelectric stacks 30 and two first connecting members 40. The two piezoelectric stacks 30 are arranged along the first direction Z, and the two first connecting members 40 are arranged along the first direction Z. The first connecting member 40 includes a first plane end and a first convex end arranged oppositely along the second direction X. The second direction X is orthogonal to the first direction Z. The amplifying mechanism 20 includes two first grooves 21 arranged along the first direction Z. The piezoelectric stack 30 includes a first end and a second end arranged oppositely along the second direction X. The first end is connected to the fixed seat 10, the second end is connected to the first plane end, and the first convex end is connected to the first groove 21. The first connecting member 40 also includes a first through hole 401 that penetrates the first connecting member 40 along the third direction Y. The third direction Y is orthogonal to the first direction Z and the second direction X, respectively. Two pre-tightening bolts 60 are arranged along the third direction Y. The fixed seat 10 also includes two second through holes 12 that are arranged along the third direction Y and penetrate the fixed seat 10 along the second direction X. The amplifying mechanism 20 further includes two screw holes 22 arranged along the third direction Y and penetrating the amplifying mechanism 20 along the second direction X. The pre-tightening bolt 60 penetrates the second through hole 12 and the screw hole 22. In the actuated state, the voltage differences applied to the two piezoelectric stacks 30 are different.

[0053] Exemplary, reference Figure 1 and Figure 2 The first connecting member 40 in the embodiment of the present invention is not only connected to the piezoelectric stack 30 in a one-to-one correspondence, but also connected to the first groove 21 in a one-to-one correspondence. Specifically, the first convex end of the first connecting member 40 and the first groove 11 of the amplifying mechanism 20 can be fixedly connected together by structural adhesive, and the first planar end of the first connecting member 40 and the second end of the piezoelectric stack 30 can be fixedly connected together, thereby realizing the connection between the piezoelectric stack 30 and the amplifying mechanism 20.

[0054] It is understandable that only by providing a certain pre-tightening force to the piezoelectric stack 30 between the fixing seat 10 and the amplifying mechanism 20 can the piezoelectric stack actuator be normally actuated. Exemplarily, the pre-tightening bolt 60 not only corresponds to the second through hole 12 one-to-one, but also corresponds to the screw hole 22 one-to-one. Two pre-tightening bolts 60 can be provided to penetrate the corresponding second through hole 12 and screw hole 22 respectively to apply a certain pre-tightening force to the piezoelectric stack 30. It should be noted that the adjustment of the magnitude of the applied pre-tightening force can be achieved by changing the length of the pre-tightening bolt 60 screwed into the screw hole 22. Those skilled in the art can set it according to actual needs, and the embodiment of the present invention is not limited to this.

[0055] The piezoelectric stack actuator in the embodiment of the present invention includes a non-actuated state and an actuated state. When the piezoelectric stack actuator is in the non-actuated state, the voltage difference applied to the two piezoelectric stacks 30 is the same, and the displacement of the two piezoelectric stacks 30 in the actuation direction is the same, and the non-piezoelectric connection section of the amplifying mechanism 20 will not swing downward or upward. When the piezoelectric stack actuator is in the actuated state, the voltage difference applied to the two piezoelectric stacks 30 is different, and the displacement of the two piezoelectric stacks 30 in the actuation direction is different, and the non-piezoelectric connection section of the amplifying mechanism 20 will swing downward or upward.

[0056] Since the first connecting member 40 is fixedly connected to the amplifying mechanism 20 and the first connecting member 40 is hollow (provided with a first through hole 401), when the piezoelectric stack actuator is in an actuated state, that is, when the non-piezoelectric connecting section of the amplifying mechanism 20 swings downward or upward, the first connecting member 40 will deform, thereby releasing part of the stress generated by the piezoelectric stack actuator in its actuated state. In this way, the stress borne by the first connecting member 40 when the amplifying mechanism moves relative to the piezoelectric stack will be reduced, making it less likely to be damaged, thereby helping to increase the service life of the piezoelectric stack actuator.

[0057] Compared with the prior art of directly fixing the piezoelectric stack 30 and the amplifying mechanism 20 together by glue, or indirectly fixing the piezoelectric stack 30 and the amplifying mechanism 20 together by a solid connecting member, the embodiment of the present invention provides a first through hole 401 on the first connecting member 40 connecting the piezoelectric stack 30 and the amplifying mechanism 20, so that the first connecting member 40 has a certain flexibility, which is beneficial to reduce the stress on the first connecting member 40 when the piezoelectric stack actuator is in an actuated state, that is, when the amplifying mechanism moves relative to the piezoelectric stack, thereby solving the problem of easy damage and short service life of the prior piezoelectric stack actuator, and having the beneficial effects of increasing the service life of the piezoelectric stack actuator and increasing repeatability accuracy.

[0058] As a feasible implementation, the first through hole 401 includes a circular hole or an oblong hole. The oblong hole includes a first semicircular hole, a second semicircular hole and a rectangular hole, and the first semicircular hole and the second semicircular hole are respectively located on two opposite sides of the rectangular hole.

[0059] For example, round holes or oblong holes are more common, and the first through hole 401 can be formed on the first connecting member 40 by directly using an existing round hole or oblong hole cutting mold, which is beneficial to reducing production costs.

[0060] As a feasible implementation method, Figure 3 A schematic diagram of the structure of a first connecting member provided in an embodiment of the present invention, referring to Figure 3, the first connecting member 40 includes a first sub-section 41, a second sub-section 42 and a third sub-section 43 arranged along the second direction X. The first sub-section 41 includes a first sub-plane end and a second sub-plane end arranged oppositely along the second direction X. The second sub-section 42 includes a third sub-plane end and a fourth sub-plane end arranged oppositely along the second direction X. The third sub-section 43 includes a fifth sub-plane end and a first sub-convex end arranged oppositely along the second direction X. The first sub-plane end is connected to the second end, the second sub-plane end is connected to the third sub-plane end, the fourth sub-plane end is connected to the fifth sub-plane end, and the first sub-convex end is connected to the first groove 21. The first through hole 401 includes a first sub-through hole 401A and a second sub-through hole 401B arranged along the first direction Z. The first sub-through hole 401A and the second sub-through hole 401B both penetrate the second sub-section 42 along the third direction Y.

[0061] It can be understood that the first sub-plane end of the first section 41 is the first plane end of the first connector 40, which can be fixedly connected to the second end of the piezoelectric stack 30 through structural adhesive. The first sub-convex surface end of the third section 43 is the first convex surface end of the first connector 40, which can be fixedly connected to the first groove 21 of the amplifying mechanism 20 through structural adhesive.

[0062] It should be noted that the first connecting member 40 in the embodiment of the present invention can be formed by connecting the first section 41, the second section 42 and the third section 43 which are manufactured separately in sequence by means of structural adhesive, or it can be formed by cutting a whole rectangular connecting member original by means of a corresponding mold.

[0063] Optionally, the material of the first connecting member 40 can be martensitic stainless steel. It should be noted that when the material of the first connecting member 40 can be martensitic stainless steel, in order to ensure that the first connecting member 40 has a certain flexibility, it is necessary to set the thickness M1 of the biconcave structure between the first sub-through hole 401A and the second sub-through hole 401B in the second section 42 along the first direction Z to meet 0.5mm≤M1≤2mm. It can be understood that the greater the thickness of the piezoelectric stack 30 along the second direction X, the greater the stress generated when the piezoelectric stack actuator is actuated, and the greater the deformation of the second section 42. In order to ensure that the second section 42 will not break, it is necessary to increase the thickness of the biconcave structure in the first direction Z of the second section 42. Those skilled in the art can reasonably set the thickness of the biconcave structure in the first direction Z of the second section 42 according to actual conditions.

[0064] Optionally, the first groove 21 includes a first concave surface extending along the third direction Y. The first sub-convex surface end includes a first sub-convex surface extending along the third direction Y. The curvature radius of the first concave surface is greater than the curvature radius of the first sub-convex surface. The first sub-convex surface is connected to the first concave surface by a first structural adhesive.

[0065] Exemplarily, the first concave surface may be a semi-cylindrical concave surface, the curvature radius of the first concave surface may be the radius of the cylindrical bottom surface corresponding to the semi-cylindrical concave surface, the first sub-convex surface may be a semi-cylindrical convex surface, and the curvature radius of the first sub-convex surface may be the radius of the cylindrical bottom surface corresponding to the semi-cylindrical convex surface. By setting the curvature radius of the first concave surface to be greater than the curvature radius of the first sub-convex surface, it is ensured that the first sub-convex surface end of the third section 43 can be inserted into the first groove 21 of the magnifying mechanism 20, and a space is left to accommodate the first structural adhesive.

[0066] Optional, reference Figure 3 , the first sub-convex surface end includes a first sub-convex curved surface extending along the third direction Y. The second sub-section 42 also includes a second sub-convex surface end and a third sub-convex surface end arranged opposite to each other along the first direction Z. The second sub-convex surface end includes a second sub-convex curved surface extending along the third direction Y. The third sub-convex surface end includes a third sub-convex curved surface extending along the third direction Y. The first sub-convex curved surface is connected to the second sub-convex curved surface and the third sub-convex curved surface respectively.

[0067] Compared to setting the second section 42 to include planar ends relatively arranged along the first direction Z, the embodiment of the present invention sets the second section 42 to include a second sub-convex end and a third sub-convex end relatively arranged along the first direction Z. When the piezoelectric stack actuator device is in an actuated state, that is, when the non-piezoelectric connection section of the amplifying mechanism 20 swings downward or upward, the deformation of the first connecting member 40 is greater, and the stress generated by the released piezoelectric stack actuator device in its actuated state is more, which can further improve the service life of the piezoelectric stack actuator device.

[0068] In order to ensure that the first connecting member 40 has a certain flexibility, it is also necessary to set the thickness M2 of the second sub-convex end along the first direction Z to meet 0.5mm≤M2≤2mm, and the thickness M3 of the third sub-convex end along the first direction Z to meet 0.5mm≤M3≤2mm. It can be understood that the greater the thickness of the piezoelectric stack 30 along the second direction Y, the greater the stress generated when the piezoelectric stack actuator is actuated, and the greater the deformation of the second section 42. In order to ensure that the second section 42 will not break, it is necessary to increase the thickness of the second sub-convex end and the third sub-convex end along the first direction Z. Those skilled in the art can reasonably set the thickness of the second sub-convex end and the third sub-convex end along the first direction Z according to actual conditions.

[0069] Based on the above embodiments, Figure 1 and Figure 2The piezoelectric stack actuator further includes two second connecting members 50 arranged along the first direction Z. The second connecting member 50 includes a second convex end and a second flat end arranged opposite to each other along the second direction X. The fixing seat 10 includes two second grooves 11 arranged along the first direction Z. The second convex end is connected to the second groove 11, and the second flat end is connected to the first end. The second connecting member 50 further includes a gap 501 penetrating the second connecting member 50 along the first direction Z.

[0070] Exemplary, reference Figure 1 and Figure 2 The second connecting member 50 in the embodiment of the present invention is not only connected to the piezoelectric stack 30 in a one-to-one correspondence, but also connected to the second groove 11 in a one-to-one correspondence. Specifically, the second convex end of the second connecting member 50 and the second groove 11 of the fixing seat 10 can be fixedly connected together by structural adhesive, and the second planar end of the second connecting member 50 and the first end of the piezoelectric stack 30 can be fixedly connected together, thereby realizing the connection between the piezoelectric stack 30 and the fixing seat 10.

[0071] It can be understood that when the piezoelectric stack actuator is in an actuated state, not only the amplifying mechanism will move relative to the piezoelectric stack, but the piezoelectric stack will also move relative to the fixed seat 10. Compared with the prior art of directly fixing the piezoelectric stack 30 and the fixed seat 10 together by glue, or indirectly fixing the piezoelectric stack 30 and the fixed seat 10 together by a solid connector, the embodiment of the present invention provides a gap 501 in the second connecting member 50 connecting the piezoelectric stack 30 and the fixed seat 10, so that the second connecting member 50 has a certain flexibility, which is beneficial to reduce the stress borne by the second connecting member 50 when the piezoelectric stack actuator is in an actuated state, that is, the piezoelectric stack will also move relative to the fixed seat 10, which is beneficial to increase the service life of the piezoelectric stack actuator.

[0072] As a feasible implementation method, Figure 4 A schematic diagram of the structure of a second connecting member provided in an embodiment of the present invention, referring to Figure 4 , the second connecting member 50 includes a fourth section 51, a fifth section 52 and a sixth section 53 arranged along the second direction X. The fourth section 51 includes a fourth sub-convex end and a sixth sub-plane end relatively arranged along the second direction X. The fifth section 52 includes a seventh sub-plane end and an eighth sub-plane end relatively arranged along the second direction X. The sixth section 53 includes a ninth sub-plane end and a tenth sub-plane end relatively arranged along the second direction X. The fourth sub-convex end is connected to the second groove 11, the sixth sub-plane end is connected to the seventh sub-plane end, the eighth sub-plane end is connected to the ninth sub-plane end, and the tenth sub-plane end is connected to the first end. The gap 501 includes a first gap 501A and a second gap 501B. Along the third direction Y, the first gap 501A and the second gap 501B are respectively located on two sides of the fifth section 52 relatively arranged.

[0073] It can be understood that the fourth sub-convex end of the fourth section 51 is the second convex end of the second connector 50, which can be fixedly connected together by structural adhesive and the second groove 11. The tenth sub-plane end of the sixth section 53 is the second plane end of the second connector 50, which can be fixedly connected together by structural adhesive and the second groove 11 of the fixing seat 10.

[0074] Optionally, the material of the second connecting member 50 can be martensitic stainless steel. It should be noted that when the material of the second connecting member 50 can be martensitic stainless steel, in order to ensure that the second connecting member 50 has a certain flexibility, it is necessary to set the thickness M4 of the fifth section 52 along the third direction Y to satisfy 0.5mm≤M4≤2mm. It can be understood that the greater the thickness of the piezoelectric stack 30 along the second direction Y, the greater the stress generated when the piezoelectric stack actuator is actuated, and the greater the deformation of the fifth section 52. In order to ensure that the fifth section 52 will not break, it is necessary to increase the thickness of the fifth section 52 along the third direction Y. Those skilled in the art can reasonably set the thickness of the fifth section 52 along the third direction Y according to actual conditions.

[0075] Optionally, the second groove 11 includes a second concave surface extending along the third direction Y. The fourth sub-convex surface end includes a fourth sub-convex surface extending along the third direction Y. The curvature radius of the second concave surface is greater than the curvature radius of the fourth sub-convex surface. The fourth sub-convex surface is connected to the second concave surface by a second structural adhesive.

[0076] Exemplarily, the second concave surface may be a semi-cylindrical concave surface, the curvature radius of the second concave surface may be the radius of the cylindrical bottom surface corresponding to the semi-cylindrical concave surface, the fourth sub-convex surface may be a semi-cylindrical convex surface, and the curvature radius of the fourth sub-convex surface may be the radius of the cylindrical bottom surface corresponding to the semi-cylindrical convex surface. By setting the curvature radius of the first concave surface to be greater than the curvature radius of the first sub-convex surface, it can be ensured that the fourth sub-convex surface end of the fourth section 51 can be inserted into the second groove 11 of the fixing seat 10, and a space for accommodating the second structural adhesive is reserved.

[0077] Based on the above embodiments, Figure 1, the two piezoelectric stacks 30 include a first piezoelectric stack 31 and a second piezoelectric stack 32. The first piezoelectric stack 31 includes a first cathode and a first anode. The second piezoelectric stack 32 includes a second cathode and a second anode. The first cathode is electrically connected to the second cathode. In a non-actuated state, the voltage applied to the first cathode is the same as that of the second cathode, and the voltage applied to the first anode is the same as that of the second anode. In an actuated state, the voltage applied to the first cathode is the same as that of the second cathode, and the voltage applied to the first anode is different from that of the second anode. Alternatively, the first anode is electrically connected to the second anode. In a non-actuated state, the voltage applied to the first anode is the same as that of the second anode, and the voltage applied to the first cathode is the same as that of the second cathode. In an actuated state, the voltage applied to the first anode is the same as that of the second anode, and the voltage applied to the first cathode is different from that of the second cathode.

[0078] It should be noted that the first piezoelectric stack 31 and the second piezoelectric stack 32 in the embodiment of the present invention are of the same model, and the relationship between the displacement along the actuation direction and the voltage difference between the anode and cathode of the two is the same. The power supply mode of the first piezoelectric stack 40 and the second piezoelectric stack 50 can be a three-wire power supply mode with a common anode or a three-wire power supply mode with a common cathode.

[0079] refer to Figure 1 It can be understood that when the voltage difference on the first piezoelectric stack 31 is greater than the voltage difference on the second piezoelectric stack 32, the amplifying mechanism 20 will swing upward, and when the voltage difference on the first piezoelectric stack 31 is less than the voltage difference on the second piezoelectric stack 32, the amplifying mechanism 20 will swing downward.

[0080] Exemplarily, when the first piezoelectric stack 31 and the second piezoelectric stack 32 are powered by a three-wire power supply system with a common anode, that is, when the first anode is electrically connected to the second anode, the movement direction of the amplifier mechanism 20 can be controlled by changing the voltage relationship between the first cathode and the second cathode.

[0081] Exemplarily, when the first piezoelectric stack 31 and the second piezoelectric stack 32 are powered by a three-wire common cathode power supply system, that is, when the first cathode is electrically connected to the second cathode, the movement direction of the amplifier mechanism 20 can be controlled by changing the voltage relationship between the first anode and the second anode.

[0082] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A piezoelectric stack actuator, characterized in that: It comprises a fixing seat, an amplifying mechanism, two piezoelectric stacks, two first connecting members and two pre-tightening bolts; the two piezoelectric stacks are arranged along a first direction, and the two first connecting members are arranged along the first direction; The first connecting member comprises a first plane end and a first convex end which are arranged opposite to each other along a second direction; the second direction is orthogonal to the first direction; The amplifying mechanism comprises two first grooves arranged along the first direction; The piezoelectric stack includes a first end and a second end disposed opposite to each other along the second direction; The first end is connected to the fixing seat, the second end is connected to the first plane end, and the first convex end is connected to the first groove; The first connecting member further comprises a first through hole penetrating the first connecting member along a third direction; the third direction is orthogonal to the first direction and the second direction respectively; The two pre-tightening bolts are arranged along the third direction; the fixing seat further comprises two second through holes arranged along the third direction and penetrating the fixing seat along the second direction; the amplifying mechanism further comprises two screw holes arranged along the third direction and penetrating the amplifying mechanism along the second direction; the pre-tightening bolt passes through the second through hole and the screw hole; In the actuated state, the voltage differences applied to the two piezoelectric stacks are different.

2. The piezoelectric stack actuator according to claim 1, characterized in that: The first connecting member includes a first sub-section, a second sub-section and a third sub-section arranged along the second direction; The first sub-section includes a first sub-plane end and a second sub-plane end that are oppositely arranged along the second direction; the second sub-section includes a third sub-plane end and a fourth sub-plane end that are oppositely arranged along the second direction; the third sub-section includes a fifth sub-plane end and a first sub-convex surface end that are oppositely arranged along the second direction; The first sub-plane end is connected to the second end, the second sub-plane end is connected to the third sub-plane end, the fourth sub-plane end is connected to the fifth sub-plane end, and the first sub-convex surface end is connected to the first groove; The first through hole includes a first sub-through hole and a second sub-through hole arranged along the first direction; the first sub-through hole and the second sub-through hole both penetrate the second section along the third direction.

3. The piezoelectric stack actuator according to claim 2, characterized in that: The first groove includes a first concave curved surface extending along the third direction; The first sub-convex surface end comprises a first sub-convex curved surface extending along the third direction; The curvature radius of the first concave surface is greater than the curvature radius of the first sub-convex surface; The first sub-convex surface is connected to the first concave surface through a first structural adhesive.

4. The piezoelectric stack actuator according to claim 2, characterized in that: The first sub-convex surface end comprises a first sub-convex curved surface extending along the third direction; The second subsection further includes a second sub-convex surface end and a third sub-convex surface end which are arranged opposite to each other along the first direction; The second sub-convex surface end includes a second sub-convex curved surface extending along the third direction; The third sub-convex surface end includes a third sub-convex curved surface extending along the third direction; The first sub-convex surface is connected to the second sub-convex surface and the third sub-convex surface respectively.

5. The piezoelectric stack actuator according to claim 1, characterized in that: The piezoelectric stack actuator further comprises two second connecting members arranged along the first direction; the second connecting member comprises a second convex end and a second flat end arranged opposite to each other along the second direction; The fixing seat comprises two second grooves arranged along the first direction; The second convex end is connected to the second groove, and the second flat end is connected to the first end; The second connecting member further includes a gap penetrating the second connecting member along the first direction.

6. The piezoelectric stack actuator according to claim 5, characterized in that: The second connecting member includes a fourth sub-section, a fifth sub-section and a sixth sub-section arranged along the second direction; The fourth subsection includes a fourth sub-convex end and a sixth sub-plane end that are oppositely arranged along the second direction; the fifth subsection includes a seventh sub-plane end and an eighth sub-plane end that are oppositely arranged along the second direction; the sixth subsection includes a ninth sub-plane end and a tenth sub-plane end that are oppositely arranged along the second direction; The fourth sub-convex surface end is connected to the second groove, the sixth sub-plane end is connected to the seventh sub-plane end, the eighth sub-plane end is connected to the ninth sub-plane end, and the tenth sub-plane end is connected to the first end; The gap includes a first gap and a second gap; along the third direction, the first gap and the second gap are respectively located on two opposite sides of the fifth section.

7. The piezoelectric stack actuator according to claim 6, characterized in that: The second groove includes a second concave curved surface extending along the third direction; The fourth sub-convex surface end includes a fourth sub-convex curved surface extending along the third direction; The curvature radius of the second concave surface is greater than the curvature radius of the fourth sub-convex surface; The fourth sub-convex surface is connected to the second concave surface through a second structural adhesive.

8. The piezoelectric stack actuator according to claim 1, wherein: The first through hole comprises a round hole or an oblong hole; The oblong hole comprises a first semicircular hole, a second semicircular hole and a rectangular hole, and the first semicircular hole and the second semicircular hole are respectively located on two opposite sides of the rectangular hole.

9. The piezoelectric stack actuator according to claim 1, wherein: The two piezoelectric stacks include a first piezoelectric stack and a second piezoelectric stack; the first piezoelectric stack includes a first cathode and a first anode; the second piezoelectric stack includes a second cathode and a second anode; The first cathode is electrically connected to the second cathode; in a non-actuated state, the voltage applied to the first cathode is the same as the second cathode, and the voltage applied to the first anode is the same as the second anode; in the actuated state, the voltage applied to the first cathode is the same as the second cathode, and the voltage applied to the first anode is different from the voltage applied to the second anode; Alternatively, the first anode is electrically connected to the second anode; In the non-actuated state, the voltage applied to the first anode and the second anode is the same, and the voltage applied to the first cathode and the second cathode is the same; In the actuated state, the voltages applied to the first anode and the second anode are the same, and the voltages applied to the first cathode and the second cathode are different.

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