A micro-motion platform

Abstract

The present application discloses a micro-motion platform, including a moving platform, a displacement output device, a flexible connection device and a mounting base; wherein the displacement output device includes: a fixed bracket, a piezoelectric ceramic driver, a high-steel spring, a push rod, and a pre-tightening device. The present application adopts piezoelectric ceramics and high-steel springs to form a driving structure that can be quickly and dynamically adjusted to achieve precise displacement output with small cumulative errors and fewer complex links. At the same time, a pre-tightening device is provided to change the pre-tightening force of the piezoelectric ceramic driver, which is conducive to improving the motion performance of the micro-motion platform and realizing motion control.

Description

Technical Field

[0001] The present application relates to the field of precision machining technology, and in particular to a micro-motion platform. Background Art

[0002] With the rapid development of modern science and technology, precision micro-motion platforms are increasingly used in micro-electromechanical systems, ultra-precision measurement and mechanical manufacturing, micro-nano processing, scanning probe microscopy, optical component manufacturing, biomedical engineering and other micro-nano technology fields. Therefore, the development of precision micro-motion platforms has become an important part of people's research in the microscopic field. For example, as a typical application of precision platforms, lithography machines are the most core key equipment in the integrated circuit industry, and precision micro-motion platforms are multi-degree-of-freedom positioning and correction compensation mechanisms in lithography systems. They are the primary conditions for achieving lithography standard line widths and obtaining high-quality lithography patterns, which determines the final lithography resolution of the lithography machine and is the core condition for achieving nanometer-level precision positioning.

[0003] Existing motion platforms are mostly driven by hydraulic and pneumatic drive. Although they have large thrust, they have low precision and require a hydraulic or pneumatic circulation system, which is not suitable for smaller micro-motion platform structures. Summary of the invention

[0004] The purpose of this application is to provide a micro-motion platform to solve the technical problems of large error and low precision.

[0005] In view of this, the present application provides a micro-motion platform, including a moving platform, a displacement output device, a flexible connection device and a mounting base;

[0006] The displacement output device comprises: a fixed bracket, a piezoelectric ceramic driver, a high-steel spring, a push rod, and a pre-tightening device;

[0007] The fixing bracket is fixed on the mounting base;

[0008] The putter comprises a contact portion, a shaft and a connecting portion, wherein the cross-sectional area of ​​the contact portion is greater than the cross-sectional area of ​​the shaft;

[0009] One end of the piezoelectric ceramic driver is fixed on the fixing bracket, and the other end is in contact with the contact portion;

[0010] The pre-tightening device comprises a cylindrical pre-tightening portion with an axial through hole, the outer surface of the pre-tightening portion is threadedly connected to the fixing bracket, and the push rod passes through the axial through hole;

[0011] The high-steel spring is sleeved on the rod, one end of which is against the contact portion and the other end is in contact with the preload device;

[0012] The connecting portion is connected to the moving platform through the flexible connecting device.

[0013] Preferably, the pre-tightening device further comprises a pre-tightening nut, and the pre-tightening nut is fixedly connected to the pre-tightening part.

[0014] Optionally, the fixing bracket is specifically a hollow cylindrical sleeve, and the piezoelectric ceramic driver is fixed inside the cylindrical sleeve and coaxially matched with the cylindrical sleeve.

[0015] Optionally, the flexible connection device is threadedly connected to the connecting portion of the push rod.

[0016] Optionally, the flexible connection device is fixed to the surface of the moving platform by screws.

[0017] Preferably, the number of the displacement output devices and the number of the flexible connection devices are both 3;

[0018] The surface of the moving platform is a triangle;

[0019] The three displacement output devices are respectively fixed to the three vertices of the moving platform through three flexible connection devices;

[0020] Preferably, the surface of the moving platform is an equilateral triangle.

[0021] Optionally, the flexible connection device includes a straight circular flexible hinge.

[0022] Compared with the prior art, the advantages of the embodiments of the present application are:

[0023] In an embodiment of the present application, a micro-motion platform is provided, including a moving platform, a displacement output device, a flexible connection device and a mounting base; wherein the displacement output device includes: a fixed bracket, a piezoelectric ceramic driver, a high-steel spring, a push rod, and a pre-tightening device. The present application adopts piezoelectric ceramics and high-steel springs to form a driving structure that can be quickly and dynamically adjusted to achieve precise displacement output with small cumulative errors and fewer complex links. At the same time, a pre-tightening device is provided to change the pre-tightening force of the piezoelectric ceramic driver, which is beneficial to improving the motion performance of the micro-motion platform and realizing motion control. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 A schematic diagram of the structure of the micro-motion platform provided in the embodiment of the present application;

[0026] Figure 2 An exploded view of the micro-motion platform provided in an embodiment of the present application;

[0027] Figure 3 A partial schematic diagram of the micro-motion platform provided in an embodiment of the present application. DETAILED DESCRIPTION

[0028] The technical solution of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0029] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0030] Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0031] See also Figures 1 to 3 , Figure 1 This is a schematic diagram of the structure of the micro-motion platform provided in the embodiment of the present application. Figure 2 This is an exploded view of the micro-motion platform provided in the embodiment of the present application. Figure 3 It is a partial schematic diagram of the micro-motion platform provided in the embodiment of the present application.

[0032] The present application designs a micro-motion platform, which includes a motion platform 1, a displacement output device, a flexible connection device 2 and a mounting base 7.

[0033] The displacement output device includes a fixed bracket 5 , a piezoelectric ceramic driver 6 , a high-steel spring 9 , a push rod 4 and a preload device 3 .

[0034] The fixing bracket 5 is fixed on the mounting base 7 to support the entire displacement output device. Optionally, the fixing bracket is fixed on the mounting base by four screws.

[0035] The push rod 4 includes a contact portion, a rod body and a connecting portion, and the cross-sectional area of ​​the contact portion is larger than the cross-sectional area of ​​the rod body. On the one hand, a larger cross-sectional area is conducive to conducting the force transmitted by the piezoelectric ceramic driver, and on the other hand, it can support the high-steel spring 9.

[0036] One end of the piezoelectric ceramic driver 6 is fixed on the fixing bracket 5, and is fixed to the mounting base 7 through the fixing bracket 5. The other end of the piezoelectric ceramic driver 6 contacts the contact part of the push rod to transmit the driving force.

[0037] The pre-tightening device 3 comprises a cylindrical pre-tightening portion with an axial through hole, the outer surface of the pre-tightening portion is threadedly connected to the fixing bracket 5, and the push rod 4 passes through the axial through hole of the pre-tightening portion.

[0038] The high-steel spring 9 is sleeved on the rod of the push rod 4, with one end against the contact part and the other end in contact with the preload device. The high-steel spring 9 can be pushed by rotating the preload device 3, thereby providing thrust to the push rod 4, so that the preload force at both ends of the piezoelectric ceramic driver 6 changes accordingly, which is conducive to finding the most suitable output displacement of the piezoelectric ceramic driver 6 under different pressures, thereby improving the motion performance of the micro-motion platform and facilitating motion control.

[0039] The connecting part of the push rod 4 is connected to the moving platform 1 through the flexible connecting device 2. The force is transmitted from the piezoelectric ceramic driver to the moving platform through the push rod 4 and the flexible connecting device 2 in sequence, so that the moving platform is displaced to achieve micro-motion.

[0040] The micro-motion platform provided in the embodiment of the present application adopts a piezoelectric ceramic and a high-steel spring 9 to form a driving structure that can be quickly and dynamically adjusted, thereby achieving a precise displacement output with small cumulative error and fewer complex links. At the same time, a pre-tightening device is provided to change the pre-tightening force of the piezoelectric ceramic driver 6, which is beneficial to improving the motion performance of the micro-motion platform and realizing motion control.

[0041] Optionally, a flexible hinge is used as an amplification mechanism and a guide mechanism, and displacement output is obtained through electromagnetic drive, which can eliminate friction and return clearance between hinges, has high precision and large stroke. Preferably, a straight circular flexible hinge structure is used as the transmission mechanism of the flexible connection device 2.

[0042] Preferably, the pre-tightening device 3 includes a pre-tightening nut, which is fixedly connected to the pre-tightening part. It is understandable that the cylindrical side of the pre-tightening part is not easy to adjust, so a hexagonal pre-tightening nut can be added, and the pre-tightening force can be conveniently adjusted by clamping the two opposite sides of the pre-tightening nut.

[0043] Preferably, in order to ensure the airtightness of the precision instrument, the fixed bracket 5 is specifically a hollow cylindrical sleeve, and the piezoelectric ceramic driver 6 is fixed inside the cylindrical sleeve and coaxially matched with the cylindrical sleeve.

[0044] Optionally, the flexible connection device 2 is processed with an internal thread, the connecting portion of the push rod 4 is processed with an external thread, and the connecting portion of the flexible connection device 2 and the push rod 4 are connected via threads.

[0045] Optionally, the flexible connection device 2 is fixed to the surface of the moving platform 1 by screws. Specifically, the number of the screws is 4 and they are arranged in a square.

[0046] Preferably, the number of displacement output devices and flexible connection devices 2 are both 3, and the surface shape of the moving platform 1 is a triangle, preferably an equilateral triangle. The three displacement output devices are fixed on the three vertices of the moving platform 1 through three flexible connection devices 2 respectively. When the three groups of piezoelectric ceramic drivers 6 are driven synchronously, the three push rods 4 rise synchronously and linearly, driving the moving platform 1 to rise so as to realize the Z-axis degree of freedom; when only one or two piezoelectric ceramic drivers 6 are driven, the moving platform 1 is rotated in space to realize two rotational degrees of freedom. The design here breaks through the limited degree of freedom of the traditional one-dimensional or two-dimensional translation micro-motion platform, increases the number of degrees of freedom of the platform, and the dual pitch structure is more conducive to the leveling and displacement correction compensation of the processing platform. The lifting and lowering movement and angle flipping of the platform are realized by the coordination of the three driving mechanisms and the deformation of the flexible structure at the flip joint, and the driving process is dynamic, flexible and adjustable. Compared with other multi-degree-of-freedom micro-motion platforms, it has a simple structure, a streamlined manufacturing process, and saves costs.

[0047] It should be understood that in the present application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A micro-motion platform, characterized in that: It includes a moving platform, a displacement output device, a flexible connection device and a mounting base; The displacement output device comprises: a fixed bracket, a piezoelectric ceramic driver, a high-steel spring, a push rod, and a pre-tightening device; The fixing bracket is fixed on the mounting base; The putter comprises a contact portion, a shaft and a connecting portion, wherein the cross-sectional area of ​​the contact portion is greater than the cross-sectional area of ​​the shaft; One end of the piezoelectric ceramic driver is fixed on the fixing bracket, and the other end is in contact with the contact portion; The pre-tightening device comprises a cylindrical pre-tightening portion with an axial through hole, the outer surface of the pre-tightening portion is threadedly connected to the fixing bracket, and the push rod passes through the axial through hole; The high-steel spring is sleeved on the rod, one end of which is against the contact portion and the other end is in contact with the preload device; The connecting portion is connected to the moving platform via the flexible connecting device; The fixed bracket is specifically a hollow cylindrical sleeve, and the piezoelectric ceramic driver is fixed inside the cylindrical sleeve and coaxially matched with the cylindrical sleeve; The number of the displacement output devices is 3; The flexible connection device comprises a straight circular flexible hinge.

2. The micro-motion platform according to claim 1, characterized in that: The pre-tightening device further comprises a pre-tightening nut, and the pre-tightening nut is fixedly connected to the pre-tightening portion.

3. The micro-motion platform according to claim 1, characterized in that: The flexible connection device is threadedly connected to the connection portion of the push rod.

4. The micro-motion platform according to claim 1, characterized in that: The flexible connection device is fixed to the surface of the moving platform by screws.

5. The micro-motion platform according to claim 1, characterized in that: The number of the flexible connection devices is 3; The surface shape of the moving platform is a triangle; The three displacement output devices are respectively fixed to the three vertices of the moving platform through three flexible connection devices.

6. The micro-motion platform according to claim 5, characterized in that: The surface of the moving platform is an equilateral triangle.

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