阅读说明：本技术 纳米级精度压电驱动线性位移台 (Nano-precision piezoelectric drive linear displacement platform ) 是由 徐金林 许智 于 2019-12-05 设计创作，主要内容包括：本发明公开了一种纳米级精度压电驱动线性位移台,其包括基体、滑轨、驱动座、柔性质量块、压电驱动单元、位置传感器单元和粘滑摩擦组件。柔性质量块和压电驱动单元之间通过球面触头和球形凹面相配合,具有自定位功能,能有效保证受力点不偏离,降低了对于加工精度和装配精度的要求,而且相对传统点接触或平面接触方式增大了接触面积,延长使用寿命；柔性质量块上的平板桥梁部具有弹性功能,能接受一定的形变,有效消除了安装误差对平面接触的影响。另外本发明的整体结构简单、紧凑,体积小巧,采用粘滑方式驱动滑轨,无上下摩擦,只存在粘滑运动中的单一摩擦,有效减小了动力损耗及对其他零部件要求,工作稳定性好,适用范围广。(The invention discloses a nanoscale precision piezoelectric driving linear displacement platform which comprises a base body, a sliding rail, a driving seat, a flexible mass block, a piezoelectric driving unit, a position sensor unit and a stick-slip friction assembly. The flexible mass block is matched with the piezoelectric driving unit through the spherical contact and the spherical concave surface, so that the piezoelectric driving unit has a self-positioning function, can effectively ensure that a stress point does not deviate, reduces the requirements on processing precision and assembly precision, increases the contact area compared with the traditional point contact or plane contact mode, and prolongs the service life; the flat bridge part on the flexible mass block has an elastic function, can accept certain deformation, and effectively eliminates the influence of installation errors on plane contact. In addition, the invention has simple and compact integral structure and small volume, adopts a stick-slip mode to drive the slide rail, has no up-down friction, only has single friction in stick-slip motion, effectively reduces power loss and requirements on other parts, and has good working stability and wide application range.)

1. The utility model provides a nanometer precision piezoelectricity drive linear displacement platform, its includes the base member and sets up the slide rail on this base member through the activity of slip subassembly, its characterized in that: the flexible mass block is provided with a square groove which is vertical to the driving direction of the piezoelectric driving unit, one side of the square groove, which is close to the spherical concave surface, is provided with a square bulge, the upper position of the flexible mass block, which corresponds to the square groove, is provided with a through groove which is consistent with the driving direction of the piezoelectric driving unit, so that the top of the flexible mass block forms a flat bridge, and the flat bridge beam is connected with the slide rail through the viscous-sliding friction component, the position sensor unit is arranged between the base body and the slide rail.

2. The nanoscale precision piezoelectric-driven linear displacement stage according to claim 1, wherein the spherical contact is fixed on a driving surface of the piezoelectric driving unit facing the compliant mass by epoxy.

3. The nano-scale precision piezoelectric driven linear displacement table according to claim 2, wherein an insulating ceramic sheet is arranged between the other driving surface of the piezoelectric driving unit and the inner wall of the assembly cavity.

4. The nanoscale precision piezoelectric-driven linear displacement stage according to claim 1, wherein the driving seat is provided with a pre-pressing screw which abuts against the flexible mass block to enable the spherical concave surface to be in close contact with the spherical contact.

5. The nanoscale precision piezoelectric driven linear displacement table according to claim 1, wherein a glue filling groove is formed on an outer side wall of the driving seat, and a guide through groove for penetrating the driving seat is formed at a position corresponding to an inner side of the glue filling groove.

6. The nanoscale precision piezoelectric-driven linear displacement stage according to claim 1, wherein the stick-slip friction assembly comprises an upper wear pad and a lower wear pad, the upper wear pad is fixed on the bottom surface of the slide rail, and the lower wear pad is fixed on the flat bridge.

7. The nanoscale precision piezoelectric-driven linear displacement table according to claim 6, wherein a limiting groove matched with the contour of the lower wear plate is arranged on the upper surface of the flat plate bridge.

8. The nanoscale precision piezoelectric-driven linear displacement stage according to claim 1, wherein the position sensor unit comprises an encoder and a linear scale, the linear scale is disposed on the bottom surface of the slide rail, and the encoder is disposed on the substrate corresponding to the position of the linear scale.

9. The nanoscale precision piezoelectric driven linear displacement table according to claim 1, wherein a pretension screw capable of pressing against the bottom surface of the driving seat is arranged at the bottom of the substrate corresponding to the flexible mass block.

10. The nanoscale precision piezoelectric-driven linear displacement stage of claim 1, wherein the slide assembly comprises a roller cage and cylindrical rollers disposed on the roller cage in an interdigitated arrangement.

Technical Field

The invention relates to the technical field of nanoscale precision displacement tables, in particular to a nanoscale precision piezoelectric drive linear displacement table.

Background

With the continuous development and updating of the technology, the requirement for precise operation on the microscopic dimension is increasing day by day, so that the nano micro-drive technology based on the piezoelectric principle is vigorously developed, is widely applied to various high-precision fields such as medicine, scientific research, aerospace, production and manufacturing and the like at present, and provides powerful technical support for the experimental research of human beings on the microscopic field and the product manufacturing.

The piezoelectric ceramic drive is used as a basic drive mode in the field of microscopic operation, the inverse piezoelectric effect of the piezoelectric ceramic is utilized, the piezoelectric ceramic is enabled to generate tiny expansion under the action of an electric field by applying the electric field to the piezoelectric ceramic, the expansion scale can reach sub-nanometer scale by accurately controlling the electric field, the expansion force is large, and the response is fast. Compared with other cross-scale motion driving modes, the stick-slip driving device has the advantages of simple and convenient driving control and principle, high resolution, large stroke, simple structure, accurate positioning, large load, easiness in miniaturization and the like.

At present, the existing stick-slip driving structure mode has larger volume, relatively complex partial structure and great improvement space in the aspect of miniaturization; in addition, the pre-tightening adjustment modes are different, up-down friction generally exists, relative sliding generally exists between the pre-tightening contact surface and the friction piece during working, requirements are made on the wear resistance of parts, and extra power loss is also generated on stick-slip movement; in addition, the good fit cannot be ensured in the assembling process, and point contact is easy to form, so that abrasion or pits appear on the friction surface in the long-time use process, and the use precision and the service life are influenced.

Disclosure of Invention

In view of the above disadvantages, the present invention aims to provide a nanoscale precision piezoelectric driven linear displacement table with smart and reasonable structural design, good matching effect, high working precision and long service life.

In order to achieve the purpose, the technical scheme provided by the invention is as follows: a nanoscale precision piezoelectric drive linear displacement platform comprises a base body, a sliding rail, a drive seat, a flexible mass block, a piezoelectric drive unit, a position sensor unit and a stick-slip friction assembly, wherein the sliding rail is movably arranged on the base body through a sliding assembly, the drive seat is arranged in the base body, an assembly cavity is formed in the drive seat, the flexible mass block and the piezoelectric drive unit are sequentially arranged in the assembly cavity, a spherical concave surface is formed in the side, facing the piezoelectric drive unit, of the flexible mass block, a spherical contact capable of being pressed against the spherical concave surface is arranged on the piezoelectric drive unit, through the cooperation of the spherical contact and the spherical concave surface, the contact area is greatly increased compared with the traditional point contact or plane contact mode, and under the long-time work of the piezoelectric drive unit, the flexible mass block is not easy to generate micro pits under the high-frequency variable acting force or micro impact by the, the stability of microcosmic displacement is influenced, and simultaneously, the sphere laminating contact has self-align function, can effectual assurance flexible hinge's stress point not deviate, promotes the work precision. The flexible mass block is provided with a square slot which is vertical to the driving direction of the piezoelectric driving unit, and one side of the square slot, which is close to the spherical concave surface, is provided with a square bulge, so that two flat flexible hinges are formed; the square slot is used for forming two flat flexible hinges which have guiding and elastic functions and form a key part for stick-slip movement. The square bumps are used for enhancing the structural strength of the rear side wall and controlling the length of the flat flexible hinge on the rear side wall. The flexible mass block is provided with a through groove corresponding to the square slot in the upper position and enabling the flexible mass block to form a flat bridge part in the top of the flexible mass block, the flat bridge part has an elastic function and can accept certain deformation, the flat bridge part is connected with the slide rail through a stick-slip friction component, and the position sensor unit is arranged between the base body and the slide rail.

As an improvement of the present invention, the spherical contact is fixed on the driving surface of the piezoelectric driving unit facing the flexible mass block through epoxy resin, so as to realize rigid connection, and the connection effect is good.

As an improvement of the invention, an insulating ceramic sheet is arranged between the other driving surface of the piezoelectric driving unit and the inner wall of the assembly cavity. The piezoelectric driving unit is specifically piezoelectric ceramic. The insulating ceramic piece has an insulating function, is high in hardness and good in rigidity, and has a gasket function and an insulating function, so that the possibility of electric leakage short circuit of the piezoelectric ceramic piece caused by uninsulated metal surface or insufficient thickness of an insulating surface layer on the metal driving seat is effectively reduced, and the service life and the reliability of the piezoelectric ceramic piece are improved.

As an improvement of the invention, the driving seat is provided with a pre-pressing screw which is pressed against the flexible mass block to enable the spherical concave surface to be in close contact with the spherical contact. By properly screwing the pre-pressing screw, the spherical concave surface of the flexible mass block can be ensured to be tightly attached to the spherical contact during installation, anti-loosening pre-tightening force is generated, and the matching effect is good.

As an improvement of the invention, the outer side wall of the driving seat is provided with a glue filling groove, a guide through groove for penetrating the driving seat is arranged at the position corresponding to the inner side of the glue filling groove, and a guide hinge which can only move up and down with a single degree of freedom is formed through the guide through groove. Be equipped with on the base member and be used for installing the drive chamber of drive seat, the drive seat is located this drive intracavity, then carries out the encapsulating through the encapsulating recess and fills, promotes the complex compactness, effectively prescribes a limit to the back-and-forth movement position of drive seat.

As an improvement of the present invention, the stick-slip friction assembly includes an upper wear pad and a lower wear pad, the upper wear pad is fixed on the bottom surface of the sliding rail, and the lower wear pad is fixed on the flat bridge. Through the cooperation of last wear pad and lower wear pad, wear-resisting effectual, increase of service life.

As an improvement of the invention, the upper surface of the flat plate bridge part is provided with a limit groove matched with the outline of the lower wear-resistant plate, so that the lower wear-resistant plate is conveniently and quickly mounted, the assembly work is convenient, and enough space is left for the self-adaptive adjustment position of the lower wear-resistant plate through clearance fit.

As an improvement of the present invention, the position sensor unit includes an encoder and a linear scale, the linear scale is disposed on the bottom surface of the slide rail, and the encoder is disposed on the base body at a position corresponding to the linear scale. The moving position of the linear scale is sensed by an encoder, and then a precise position signal is output.

As an improvement of the invention, a pretightening screw capable of being pressed against the bottom surface of the driving seat is arranged at the position, corresponding to the flexible mass block, of the bottom of the base body. When the pre-tightening screw is screwed, the driving seat can be pushed to move upwards, the flat bridge beam part on the flexible mass block is influenced by displacement to generate larger deformation, the positive pressure of the upper wear-resisting sheet and the lower wear-resisting sheet is increased, and the range adjustment of the friction force between the friction pieces is realized.

As a refinement of the invention, the sliding assembly comprises a roller cage and cylindrical rollers arranged on the roller cage in an interdigitating arrangement. The device can bear loads in all directions and realize high-precision and stable linear motion.

The invention has the beneficial effects that: the flexible mass block is matched with the piezoelectric driving unit through the spherical contact and the spherical concave surface, so that the flexible mass block has a self-positioning function, the stress point can be effectively prevented from deviating, the working precision is improved, the requirements on the processing precision and the assembling precision are reduced, the contact area is greatly increased compared with the traditional point contact or plane contact mode, the flexible mass block is not easy to generate a tiny pit under the high-frequency variable acting force or tiny impact by the spherical contact, the stability of microscopic displacement is prevented from being influenced, and the working stability is ensured; the flat bridge part on the flexible mass block has an elastic function and can accept certain deformation, so that the upper wear plate and the lower wear plate can realize better plane contact, the influence of installation errors on the plane contact is eliminated, meanwhile, the influence of contact position drift and positive pressure jump change caused by flatness errors generated by the machining precision of the upper wear plate and the lower wear plate during movement can be reduced, and the flexible mass block has certain self-adaptability. In addition, the invention has simple and compact integral structure and small volume, adopts a stick-slip mode to drive the slide rail, has no up-down friction, only has single friction in stick-slip motion, effectively reduces power loss and requirements on other parts, is easy to realize, has good working stability and long service life, and is beneficial to wide popularization and application.

The invention is further described with reference to the following figures and examples.

Drawings

Fig. 1 is a schematic perspective view of the present invention.

Fig. 2 is a schematic cross-sectional structure of the present invention.

Fig. 3 is a schematic exploded view of the present invention.

Fig. 4 is a schematic structural view of the driving seat in the present invention.

Fig. 5 is a schematic perspective view of a flexible mass according to the present invention.

Fig. 6 is a schematic cross-sectional view of a flexible mass according to the present invention.

Detailed Description

Referring to fig. 1 to 6, the present embodiment provides a nanometer-scale precision piezoelectric-driven linear displacement table, which includes a substrate 1, a sliding rail 3 movably disposed on the substrate 1 through a sliding assembly 2, a driving seat 4, a flexible mass block 5, a piezoelectric driving unit 6, a position sensor unit 7, and a stick-slip friction assembly 8. The stick-slip friction assembly 8 includes an upper wear plate 81 and a lower wear plate 82.

The driving seat 4 is arranged in the base body 1, specifically, the base body 1 is provided with a driving cavity 101 for installing the driving seat 4, the driving seat 4 is located in the driving cavity 101, the outer side wall of the driving seat 4 is provided with a glue filling groove 41, a guiding through groove 42 for penetrating the driving seat 4 is arranged at the inner side position corresponding to the glue filling groove 41, and a guiding hinge which can only move up and down with a single degree of freedom is formed through the guiding through groove 42. The glue filling groove 41 is filled with glue, the matching tightness of the driving seat 4 and the inner wall of the driving cavity 101 is improved, the whole driving seat 4 is effectively limited to move back and forth, and the vertical micro displacement is supported. And a pre-tightening screw 11 capable of being pressed against the bottom surface of the driving seat 4 is arranged at the position, corresponding to the flexible mass block 5, of the bottom of the base body 1. When the pretightening screw 11 is screwed, the driving seat 4 can be pushed to move upwards, the flat bridge portion 52 on the flexible mass block 5 is influenced by displacement to generate larger deformation, the positive pressure of the upper wear-resistant piece 81 and the lower wear-resistant piece 82 is increased, and the range adjustment of the friction force between the friction pieces is realized.

The driving seat 4 is provided with an assembly cavity 43, the flexible mass block 5 and the piezoelectric driving unit 6 are sequentially arranged in the assembly cavity 43, and the bottom surface of the flexible mass block 5 is a plane and is rigidly connected with the driving seat 4 through epoxy resin.

The side surface, facing the piezoelectric driving unit 6, of the flexible mass block 5 is provided with a spherical concave surface 51, the piezoelectric driving unit 6 is provided with a spherical contact 9 capable of being pressed against the spherical concave surface 51, and the spherical contact 9 is fixed on the driving surface, facing the flexible mass block 5, of the piezoelectric driving unit 6 through epoxy resin, so that rigid connection is realized, and the connection effect is good. During operation, cooperate through this spherical contact 9 and spherical concave 51, the contact area has been increased greatly to traditional point contact or plane contact mode relatively, under piezoelectric drive unit 6 long-time work for flexible quality piece 5 is difficult to produce small pit by spherical contact 9 under high frequency change effort or small striking, influences the stability of microcosmic displacement, and simultaneously, the sphere laminating contact has from the locate function, can effectually guarantee that flexible hinge's stress point does not deviate, promotes the work precision.

Preferably, a pre-pressing screw 10 is provided on the driving seat 4 to abut against the flexible mass 5 to tightly contact the spherical concave 51 with the spherical contact 9. Specifically, the front side of the driving seat 4 protrudes upwards to form a front blocking portion, a threaded hole 44 matched with the pre-pressing screw 10 is formed in the front blocking portion, the pre-pressing screw 10 is screwed into the threaded hole 44 and is pressed against the front side wall of the flexible mass block 5, the spherical concave surface 51 of the flexible mass block 5 can be tightly attached to the spherical contact 9 during installation by properly screwing the pre-pressing screw 10, anti-loosening pre-tightening force is generated, and the matching effect is good.

An insulating ceramic sheet 12 is arranged between the other driving surface of the piezoelectric driving unit 6 and the inner wall of the assembly cavity 43. The piezoelectric driving unit 6 is specifically piezoelectric ceramic. The insulating ceramic sheet 12 has an insulating function, high hardness and good rigidity, and simultaneously has a gasket function and an insulating function, thereby effectively reducing the possibility of piezoelectric ceramic leakage short circuit caused by uninsulated metal surface or insufficient thickness of an insulating surface layer on the driving seat 4 made of metal material, and improving the service life and reliability of the piezoelectric ceramic.

The flexible mass block 5 is provided with a square slot 53 perpendicular to the driving direction of the piezoelectric driving unit 6, so that two flat flexible hinges are formed, have guiding and elastic functions and form a key part for stick-slip motion. A square protrusion 54 is disposed on one side of the square slot 53 close to the spherical concave surface 51, so as to enhance the structural strength of the rear sidewall and control the length of the flat flexible hinge on the rear sidewall. The flexible mass block 5 is provided with a through groove 55 corresponding to the driving direction of the piezoelectric driving unit 6 above the square open groove 53, so that the top of the flexible mass block 5 forms the flat bridge portion 52, the flat bridge portion 52 has an elastic function and can be deformed to a certain extent, and the flat bridge portion 52 is connected with the slide rail 3 through the stick-slip friction component 8. Specifically, the stick-slip friction assembly 8 includes an upper wear pad 81 and a lower wear pad 82, the upper wear pad 81 is rigidly fixed to the bottom surface of the slide rail 3 through epoxy resin, and the lower wear pad 82 is fixed to the flat bridge portion 52. In this embodiment, the upper wear-resistant sheet 81 is preferably a sapphire wafer; the lower wear plate 82 is preferably a sapphire square plate; the sapphire is selected, so that the wear-resisting effect is good, and the service life is long. In other embodiments, the upper wear-resistant plate 81 and the lower wear-resistant plate 82 may be made of other materials and have other shapes. The upper surface of the flat bridge portion 52 is provided with a limiting groove 56 matched with the outline of the lower wear-resistant sheet 82, the lower wear-resistant sheet 82 is preferably in clearance fit with the limiting groove 56, that is, the size of the inner cavity of the limiting groove 56 is slightly larger than the outline of the lower wear-resistant sheet 82, enough space is reserved for adaptive position adjustment of the upper wear-resistant sheet 81, the upper wear-resistant sheet 81 is loosely mounted in the limiting groove 56, and then the upper wear-resistant sheet is rigidly fixed through epoxy resin.

The position sensor unit 7 is arranged at a position between the base body 1 and the slide rail 3. Specifically, the position sensor unit 7 includes an encoder 71 and a linear scale 72, the linear scale 72 is disposed on the bottom surface of the slide rail 3, and the encoder 71 is disposed on the base 1 at a position corresponding to the linear scale 72. The moving position of the linear scale 72 is sensed by the encoder 71, and then a precise position signal is output.

In this embodiment, the sliding assembly 2 is preferably a cross roller assembly, which can bear loads in various directions and realize high-precision and stable linear motion. Specifically, the cross roller assembly includes a roller cage and cylindrical rollers disposed on the roller cage in an interdigitated arrangement. The cross roller assembly and the slide rail 3 are assembled to form a cross roller guide rail which can be directly purchased in the market.

When the device works, the slide rail 3 is driven in a stick-slip mode, no up-down friction exists, only single friction exists in stick-slip motion, power loss and requirements on other parts are effectively reduced, working stability is good, and the service life is long. And the flexible mass block 5 is matched with the piezoelectric driving unit 6 through the spherical contact 9 and the spherical concave surface 51, so that the self-positioning function is realized, the stress point can be effectively ensured not to deviate, the working precision is improved, meanwhile, the requirements on the processing precision and the assembling precision are also reduced, in addition, the contact area is greatly increased compared with the traditional point contact or plane contact mode, the flexible mass block 5 is difficult to generate a small pit by the spherical contact 9 under the high-frequency variable acting force or small impact, the influence on the stability of microscopic displacement is avoided, and the working stability is ensured. In addition, the flat bridge 52 on the flexible mass block 5 has an elastic function and can receive a certain deformation, so that the upper wear-resistant plate 81 and the lower wear-resistant plate 82 realize better plane contact, and the influence of installation errors on the plane contact is eliminated; meanwhile, the contact positions of the upper wear-resistant sheet 81 and the lower wear-resistant sheet 82 shift during movement due to flatness errors caused by machining precision, so that the positive pressure jumps greatly, the influence of the micro deformation of the flat bridge portion 52 can be reduced, and the flat bridge portion has certain adaptability. The nano-scale precision piezoelectric driving linear displacement platform can perform micro-nano operation in vacuum, has small current, small heat generation and no electromagnetic field compared with motor driving, has greater advantages in the field with extremely high operation requirements, and can be applied to various high-precision fields such as scientific research, semiconductors, biological medicines, advanced manufacturing, optics/communication, aerospace and the like.

Variations and modifications to the above-described embodiments may occur to those skilled in the art, which fall within the scope and spirit of the above description. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and variations of the present invention should fall within the scope of the claims of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. Other displacement tables having the same or similar structure as those described in the above embodiments of the present invention are within the scope of the present invention.