阅读说明：本技术 一种压电叠堆位移驱动结构 (Piezoelectric stack displacement driving structure ) 是由 徐子政 耿晓勇 林少渊 于 2019-12-25 设计创作，主要内容包括：本发明属于压电叠堆装置技术领域,公开了一种压电叠堆位移驱动结构,包括压电堆叠部、顶杆固定座、放大臂以及撞针。其中压电堆叠部是由多个压电陶瓷片堆叠而成的棒状结构,压电堆叠部的两端分别连接前顶块和后顶块,后顶块与固定块连接；顶杆固定座设于前顶块的下方,顶杆固定座上铰接有顶杆；放大臂的根部与顶杆连接,放大臂的中部向上凸起并与前顶块接触；撞针的针帽能够与放大臂的末端接触。该压电叠堆位移驱动结构通过杠杆原理可以将压电堆叠部的微小位移通过放大臂放大实现撞针的长行程位移,提高包括该压电叠堆位移驱动结构的产品的精度和效率,获得更好的控制效果。(The invention belongs to the technical field of piezoelectric stack devices, and discloses a piezoelectric stack displacement driving structure which comprises a piezoelectric stack part, a push rod fixing seat, an amplifying arm and a firing pin. The piezoelectric stacking part is of a rod-shaped structure formed by stacking a plurality of piezoelectric ceramic plates, two ends of the piezoelectric stacking part are respectively connected with a front top block and a rear top block, and the rear top block is connected with a fixed block; the ejector rod fixing seat is arranged below the front ejector block, and an ejector rod is hinged to the ejector rod fixing seat; the root of the amplifying arm is connected with the ejector rod, and the middle part of the amplifying arm protrudes upwards and is contacted with the front ejector block; the needle cap of the striker is capable of contacting the distal end of the amplifying arm. The piezoelectric stack displacement driving structure can amplify the micro displacement of the piezoelectric stack part through the amplifying arm to realize the long-stroke displacement of the firing pin through the lever principle, improve the precision and the efficiency of a product comprising the piezoelectric stack displacement driving structure, and obtain a better control effect.)

1. A piezoelectric stack displacement drive structure, comprising:

the piezoelectric stacking part (3) is of a rod-shaped structure formed by stacking a plurality of piezoelectric ceramic plates, a front ejector block (4) and a rear ejector block (2) are respectively arranged at two ends of the piezoelectric stacking part (3), and the rear ejector block (2) is connected with the fixed block (1);

the ejector rod fixing seat (6) is arranged below the front ejector block (4), and an ejector rod (5) is hinged to the ejector rod fixing seat (6);

the root of the amplifying arm (7) is connected with the ejector rod (5), and the middle of the amplifying arm (7) protrudes upwards and is in contact with the front ejector block (4);

a striker (11), the cap of which striker (11) is contactable with the tip of the magnifying arm (7).

2. The piezoelectric stack displacement driving structure according to claim 1,

the elastic reset structure is arranged on the firing pin (11) and can reset the firing pin (11).

3. The piezoelectric stack displacement driving structure according to claim 2,

the elastic reset structure comprises:

the spring fixing seat (10) is arranged at the lower part of the elastic resetting structure, a needle hole is formed in the middle of the spring fixing seat (10), and a needle head of the firing pin (11) penetrates through the needle hole downwards and is movably connected with the spring fixing seat (10);

and the first spring (8) is sleeved on the firing pin (11) and is arranged between the spring fixing seat (10) and the needle cap.

4. The piezoelectric stack displacement driving structure according to claim 3,

and a second spring (9) which is connected with the first spring (8) in parallel and sleeved on the firing pin (11) is also arranged in the first spring (8).

5. The piezoelectric stack displacement driving structure according to claim 1,

the elastic reset structure is arranged at the joint of the amplifying arm (7) and the ejector rod (5) and can reset the amplifying arm (7).

6. The piezoelectric stack displacement driving structure according to claim 5,

the elastic reset structure comprises a torsion spring, one end of the torsion spring is fixed on the ejector rod fixing seat (6), and the other end of the torsion spring is in contact with the amplifying arm (7).

7. The piezoelectric stack displacement driving structure according to claim 6,

the cap of the striker (11) is fixed to the end of the magnifying arm (7).

8. The piezoelectric stack displacement driving structure according to claim 7,

the included angle between the connecting line of the tail end of the amplifying arm (7) and the rotation center of the amplifying arm (7) and the direction of the output displacement of the piezoelectric stacking part (3) is 85-95 degrees.

9. The piezoelectric stack displacement driving structure according to claim 8,

the connecting line of the tail end of the amplifying arm (7) and the rotation center of the amplifying arm (7) is perpendicular to the direction of the output displacement of the piezoelectric stacking part (3).

Technical Field

The invention relates to the technical field of piezoelectric stack devices, in particular to a piezoelectric stack displacement driving structure.

Background

The piezoelectric driver is a novel micro driver for converting input electric energy into output mechanical energy by utilizing the inverse piezoelectric effect of a piezoelectric ceramic material, and has the advantages of simple structure, easy miniaturization, no electromagnetic interference, high response speed and the like, so that the piezoelectric driver is widely concerned by researchers at home and abroad in recent years, and has been successfully applied to the fields of ultraprecision machining, robot joints, aerospace, digital electronic products, biomedical equipment and the like.

Among various piezoelectric drivers, the multi-layer piezoelectric stack driver is most widely used. The piezoelectric stack refers to that a plurality of piezoelectric ceramic pieces are connected in series, in parallel or in series physically. The advantage of the piezoelectric stack is that the efficiency is higher than that of a monolithic piece. All piezoelectric sheets in the stack are energized in one compression. The multilayer piezoelectric stack driver is mainly formed by overlapping a plurality of piezoelectric ceramic sheets and electrode sheets, wherein the electrode sheets are alternately connected to outer electrodes at two ends of the driver, so that the plurality of piezoelectric ceramic sheets form a plurality of micro-displacement output units, when electric signal excitation is applied, the output displacement of the multilayer piezoelectric stack driver is the sum of the output micro-displacement of each layer of piezoelectric ceramic sheet, and the multilayer piezoelectric stack driver is widely applied to the fields of superfinishing, micro-displacement platforms, robotics and the like. However, the displacement of the multi-layer piezo stack driver is still small, and in practical use, the displacement of the piezo stack structure is often required to be amplified to obtain a better control effect.

Disclosure of Invention

In view of the defects in the prior art, an object of the present invention is to provide a piezoelectric stack displacement driving structure capable of amplifying the displacement of a piezoelectric stack structure.

In order to achieve the purpose, the invention adopts the following technical scheme:

a piezoelectric stack displacement drive structure comprising:

the piezoelectric stacking part is of a rod-shaped structure formed by stacking a plurality of piezoelectric ceramic plates, a front jacking block and a rear jacking block are respectively arranged at two ends of the piezoelectric stacking part, and the rear jacking block is connected with the fixed block;

the ejector rod fixing seat is arranged below the front ejector block, and an ejector rod is hinged to the ejector rod fixing seat;

the root part of the amplifying arm is connected with the ejector rod, and the middle part of the amplifying arm protrudes upwards and is in contact with the front ejector block;

a striker, a needle cap of which is contactable with a tip of the amplifying arm.

Preferably, the elastic return structure is provided on the striker, and is capable of returning the striker.

Preferably, the elastic reset structure comprises:

the spring fixing seat is arranged at the lower part of the elastic reset structure, a needle eye is arranged in the middle of the spring fixing seat, and a needle head of the firing pin downwards penetrates through the needle eye and is movably connected with the spring fixing seat;

the first spring is sleeved on the firing pin and arranged between the spring fixing seat and the needle cap.

Preferably, a second spring is further disposed inside the first spring, and is connected in parallel with the first spring and sleeved on the striker.

Preferably, the elastic restoring structure is provided at a joint between the amplifying arm and the jack, and is capable of restoring the amplifying arm.

Preferably, the elastic reset structure comprises a torsion spring, one end of the torsion spring is fixed on the ejector rod fixing seat, and the other end of the torsion spring is in contact with the amplifying arm.

Preferably, the needle cap of the striker is fixed to a distal end of the enlargement arm.

Preferably, an angle between a line connecting the distal end of the amplifying arm and the rotation center of the amplifying arm and the direction of the output displacement of the piezoelectric stack portion is 85 ° to 95 °.

Preferably, a line connecting a distal end of the amplification arm and a rotation center of the amplification arm is perpendicular to a direction of the output displacement of the piezoelectric stack portion.

The invention has the beneficial effects that: the piezoelectric stack displacement driving structure can amplify the micro displacement of the piezoelectric stack part through the amplifying arm to realize the long-stroke displacement of the firing pin through the lever principle, improve the precision and the efficiency of a product comprising the piezoelectric stack displacement driving structure, and obtain a better control effect.

Drawings

Fig. 1 is a schematic structural diagram of a displacement driving structure of a piezoelectric stack according to an embodiment of the present invention.

In the figure:

1. a fixed block; 2. a rear ejector block; 3. a piezoelectric stack portion; 4. a front top block; 5. a top rod; 6. a mandril fixing seat; 7. an amplifying arm; 8. a first spring; 9. a second spring; 10. a spring fixing seat; 11. a striker.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "right", etc. are used in an orientation or positional relationship based on that shown in the drawings only for convenience of description and simplicity of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes to distinguish one from another.

As shown in fig. 1, the present invention provides a piezoelectric stack displacement driving structure, which includes a piezoelectric stack portion 3, a push rod fixing seat 6, an amplifying arm 7 and a striker 11. The piezoelectric stacking part 3 is a rod-shaped structure formed by stacking a plurality of piezoelectric ceramic plates, two ends of the piezoelectric stacking part 3 are respectively connected with the front top block 4 and the rear top block 2, and the rear top block 2 is connected with the fixed block 1; the ejector rod fixing seat 6 is arranged below the front ejector block 4, and an ejector rod 5 is hinged on the ejector rod fixing seat 6; the root of the amplifying arm 7 is connected with the ejector rod 5, and the middle part of the amplifying arm 7 protrudes upwards and is in contact with the front ejector block 4; the cap of the striker 11 can come into contact with the tip of the magnifying arm 7.

The piezoelectric stack displacement driving structure can amplify the micro displacement of the piezoelectric stack part 3 through the amplifying arm 7 by a lever principle to realize the long-stroke displacement of the firing pin 11, so that the precision and the efficiency of a product comprising the piezoelectric stack displacement driving structure are improved, and a better control effect is obtained.

Embodiments of the present embodiment will be described below with reference to the drawings.

As shown in fig. 1, the piezoelectric stack portion 3 is a rod-shaped structure arranged in the vertical direction, and is formed by stacking a plurality of piezoelectric ceramic sheets. The upper end of the piezoelectric stack 3 is fixed to the fixing block 1, and when an electrical signal is applied to excite the piezoelectric stack 3, the piezoelectric stack 3 can be deformed in the length direction, thereby generating an output displacement at the lower end of the piezoelectric stack 3. In order to protect the piezoelectric stack part 3, the piezoelectric stack part 3 is prevented from being directly contacted with other structural members to be abraded, meanwhile, the piezoelectric stack part 3 is conveniently arranged, a rear top block 2 is arranged between the upper end of the piezoelectric stack part 3 and the fixed block 1, and a front top block 4 is arranged between the lower end of the piezoelectric stack part 3 and the amplifying arm 7. In order to avoid great influence on the precision of the piezoelectric stack displacement driving structure caused by the compression deformation of the front top block 4, the rear top block 2 and the fixed block 1, the front top block 4, the rear top block 2 and the fixed block 1 are all made of materials with high compressive strength.

In this embodiment, the ejector rod fixing seat 6 serves as a support structure of the ejector rod 5 and is fixed to an external structure, and the ejector rod 5 is connected to the amplifying arm 7 and hinged to the ejector rod fixing seat 6. The ejector rod 5, the amplifying arm 7 and the front ejector block 4 form a lever structure, wherein the contact point of the front ejector block 4 and the amplifying arm 7 forms a fulcrum of the lever structure, and when the fulcrum is displaced by S1, a larger displacement S2 occurs at the tail end of the amplifying arm 7, so that the small displacement of the piezoelectric stack part 3 is amplified by the amplifying arm 7 to form a long-stroke displacement. To facilitate the measurement or utilization of this long stroke displacement, a vertically arranged striker 11 is attached to the end of the amplifying arm 7.

Since the amplifying arm 7 is forced to rotate around the hinge axis of the ejector 5 and the ejector fixing seat 6 when the piezoelectric stack 3 generates the output displacement, in order to avoid that the displacement in the horizontal direction generated by the striker 11 and the contact point of the front ejector block 4 and the amplifying arm 7 has a large influence on the accuracy of the piezoelectric stack displacement driving structure, the angle between the line connecting the end of the amplifying arm 7 and the rotation center of the amplifying arm 7 and the direction of the output displacement of the piezoelectric stack 3 is 85 ° -95 °, that is, the angle of α in fig. 1 is ± 5 °.

In order to enable the striker 11 to reset after the forced displacement, an elastic resetting structure is further arranged on the striker 11. The elastic reset structure comprises a spring fixing seat 10 and a first spring 8. Wherein, spring fixing base 10 is located the lower part of elasticity reset structure, and spring fixing base 10 middle part is equipped with the pinhole, and the syringe needle of firing pin 11 passes the pinhole downwards and can freely stretch out and draw back in spring fixing base 10. The first spring 8 is sleeved on the striker 11 and arranged between the spring fixing seat 10 and the needle cap, and when the electric signal excitation disappears, the striker 11 and the amplifying arm 7 can be reset under the action of the elastic force of the first spring 8.

In order to improve the performance of the elastic reset structure, a second spring 9 which is connected with the first spring 8 in parallel and sleeved on the firing pin 11 is further arranged inside the first spring 8, and the first spring 8 and the second spring 9 form a parallel double-spring form.

In other embodiments, an elastic resetting structure may also be disposed at the connection between the amplifying arm 7 and the push rod 5 to reset the amplifying arm 7 and further reset the striker 11. At this time, a torsion spring may be used as a main elastic structural member of the elastic restoring structure. Specifically, one end of a torsion spring is fixed to the jack holder 6, and the other end of the torsion spring is in contact with the enlargement arm 7, and fixes the cap of the striker 11 to the tip of the enlargement arm 7. When the piezoelectric stack part 3 applies electric signal excitation to generate micro displacement, the amplifying arm 7 is forced to rotate anticlockwise around the ejector rod 5, and the torsion spring is pressed to generate deformation. Then the piezoelectric stack part 3 discharges and contracts to move upwards, the torsion spring restores to a stable state, the amplifying arm 7 rotates clockwise, and the thimble is driven to move upwards to return to an initial state.

In summary, the piezoelectric stack displacement driving structure has the following advantages:

1. the piezoelectric stack displacement driving structure can amplify the tiny displacement of the piezoelectric stack part 3 through the amplifying arm 7 by a lever principle to realize the long-stroke displacement of the striker 11.

2. The piezoelectric stack displacement driving structure adopts a parallel double-spring form as an elastic reset structure, has compact structure and large bearing capacity, and is beneficial to improving the overall performance of the piezoelectric stack displacement driving structure.

3. The included angle between the connecting line of the tail end of the amplifying arm 7 and the rotation center of the amplifying arm 7 and the direction of the output displacement of the piezoelectric stacking part 3 is 85-95 degrees, and the measurement precision is high.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Numerous obvious variations, adaptations and substitutions will occur to those skilled in the art without departing from the scope of the invention. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.