CN117656012A - Displacement table capable of being adjusted in multiple degrees of freedom - Google Patents

Abstract

The invention relates to a displacement table capable of being adjusted in multiple degrees of freedom, which comprises a base, a plurality of guide rail mechanisms, a carrying table and a driving assembly, wherein the guide rail mechanisms are arranged on the base at intervals; the carrier is rotatably connected with the moving assembly in each guide rail mechanism; the driving component is connected with the moving component to drive the moving component to move relative to the fixed component so as to realize the multi-degree-of-freedom adjustment of the carrier; the movable assembly can be air-floated on the fixed assembly, so that when the movable assembly moves relative to the fixed assembly, friction is avoided between the movable assembly and the fixed assembly. Through setting up movable component into can be by the air supporting on fixed subassembly to when making movable component remove relative fixed subassembly, can not produce the friction between movable component and the fixed subassembly, thereby make the displacement adjustment precision of displacement platform higher, stability better.

Description

Displacement table capable of being adjusted in multiple degrees of freedom

Technical Field

The invention relates to the technical field of precision platforms, in particular to a displacement platform capable of being adjusted in multiple degrees of freedom.

Background

As the semiconductor industry continues to develop, higher precision and efficiency requirements are placed on precision machining processes and precision equipment. Meanwhile, the detection precision is higher aiming at the requirements of visual detection equipment, and the structural space is more compact; in particular, the requirements for the capability of detecting defects on wafers are higher for the semiconductor wafer detection industry. For such high-precision wafer inspection equipment, the demand in the industry is increasing year by year. Due to the specificity of wafer detection, the surface height and horizontal position of the wafer need to be adjusted in the detection process.

In the related art, a carrying platform for placing wafers is connected with a base through a plurality of driving pieces, the carrying platform is hinged with the driving pieces, the driving pieces are in linear sliding connection with the base, and when the driving pieces linearly move along the base in the horizontal direction, the driving pieces can drive the position connected with the carrying platform to vertically move, so that the height and the horizontal position of the carrying platform are adjusted. However, the driving member and the base in the related art have mechanical friction, which results in the displacement table having defects of poor positioning accuracy and stability and short service life.

Disclosure of Invention

Based on the above, it is necessary to provide a displacement table capable of adjusting multiple degrees of freedom, which aims at the technical problems of poor positioning accuracy, poor stability and short service life of the displacement table in the related art.

A multi-degree-of-freedom adjustable displacement stage, the multi-degree-of-freedom adjustable displacement stage comprising:

a base;

the guide rail mechanisms are arranged on the base at intervals, each guide rail mechanism comprises a fixed component and a movable component, the fixed component is fixedly connected to the base, and the fixed component and the movable component can be mutually limited;

the carrier is rotatably connected with the moving assembly in each guide rail mechanism;

the driving end of the driving assembly is connected with the moving assembly to drive the moving assembly to move relative to the fixed assembly so as to realize the multi-degree-of-freedom adjustment of the carrier;

the movable assembly can be air-floated on the fixed assembly, so that friction is avoided between the movable assembly and the fixed assembly when the movable assembly moves relative to the fixed assembly.

In one embodiment, the mobile assembly comprises:

the first moving assembly is in sliding connection with the fixed assembly and can move along a first direction relative to the fixed assembly;

the second moving assembly is connected with the first moving assembly in a sliding manner and is linked with the first moving assembly, the second moving assembly can move along a second direction relative to the first moving assembly, and the second moving assembly is rotatably connected with the carrying platform;

wherein the first direction is perpendicular to the second direction.

In one embodiment, the stationary assembly includes a linear bearing fixedly coupled to the base, the linear bearing extending along the first direction; the first moving assembly is provided with a guide chute, the guide chute is in guide fit with the linear bearing, air-float gas can flow into the space between the groove wall of the guide chute and the linear bearing, and an air film gap is formed between the groove wall of the guide chute and the linear bearing, so that the first moving assembly floats relative to the linear bearing in a direction away from the linear bearing.

In one embodiment, the first moving assembly comprises:

the wedge-shaped guide rail comprises a first surface and a second surface which are oppositely arranged, the first surface is opposite to the linear bearing, the second surface is configured as an inclined surface, and the distance between the first surface and the second surface is gradually reduced along the first direction;

the wedge-shaped guide rail is arranged between the two side plates and fixedly connected with the two side plates, and the side surfaces of the two side plates and the first surface are enclosed to define the guide chute;

the second moving assembly is matched with the second face, the wedge-shaped guide rail moves along the first direction relative to the linear bearing, and the second face pushes the second moving assembly to move along the second direction.

In one embodiment, the second moving assembly comprises:

the wedge-shaped bearing comprises a wedge-shaped surface, and the wedge-shaped surface is attached to the second surface;

the bearing seat is fixedly connected to the side surface of the wedge-shaped bearing, which is away from the wedge-shaped surface;

the spherical hinge bearing is rotationally connected with the bearing seat and fixedly connected with the carrier;

when the wedge-shaped guide rail moves along the first direction relative to the linear bearing, the wedge-shaped bearing moves along the second direction under the action of the second surface, so that the spherical hinge bearing rotates relative to the bearing seat.

In one embodiment, the second moving assembly further comprises:

the first absorption part is fixedly connected with the wedge-shaped surface of the wedge-shaped bearing;

the second surface of the wedge-shaped guide rail is provided with an accommodating groove, the first absorption part is slidably arranged in the accommodating groove, and absorption force can be generated between the first absorption part and the wedge-shaped guide rail so as to display that the wedge-shaped bearing moves relative to the wedge-shaped guide rail.

In one embodiment, the displacement stage further comprises:

the magnetic balance stator is fixedly connected to the base;

the magnetic balance rotor is fixedly connected to one of the side plates and matched with the magnetic balance stator, the magnetic balance rotor can provide thrust for the side plates along the first direction, and the thrust is opposite to the direction of the component of the gravity applied to the wedge-shaped guide rail by the second moving assembly along the first direction.

In one embodiment, the securing assembly further comprises:

the throttle plate is covered on the linear bearing;

a plurality of first throttles provided on the throttle plate;

the first pneumatic connector is arranged at one end of the linear bearing and is used for being connected with an air source;

the linear bearing is provided with a first air passage, and the first air passage is communicated with the first air connector and the first throttle, so that the air-float gas flows into a gap between the guide chute and the linear bearing from the first throttle.

In one embodiment, the mobile assembly comprises:

the air inlet plate is fixedly connected with the second moving assembly, and a second air passage is arranged on the air inlet plate;

the second pneumatic connector is connected with the air inlet plate and communicated with the second air passage, and the second pneumatic connector is also connected with an air source;

the air-bearing gas can flow into the second air passage through the second pneumatic connector and flow from the second air passage to between the first moving assembly and the second moving assembly to create an air film gap between the first moving assembly and the second moving assembly.

In one embodiment, the multi-degree of freedom adjustable displacement stage further comprises:

the second absorbing part is fixedly connected to the base and can generate absorbing force with the moving assembly so as to limit the moving assembly to move relative to the base.

The invention has the beneficial effects that:

the invention provides a displacement table capable of being adjusted in multiple degrees of freedom, wherein a base is used for supporting and connecting a guide rail mechanism and a carrying table. The fixed component in the guide rail mechanism is fixedly connected with the base, the movable component is in sliding connection with the fixed component, the carrier is rotatably connected with the movable component, and when the driving component drives the movable component to move relative to the fixed component, the angle or position of the carrier can be changed. And a plurality of guide rail mechanisms are arranged on the base at intervals, so that the adjustment of the multiple degrees of freedom of the carrier is realized by moving components in different guide rail mechanisms. And through setting up the movable assembly into can be by the air supporting on fixed subassembly to when making movable assembly relatively fixed subassembly remove, can not produce the friction between movable assembly and the fixed subassembly, thereby make the displacement of displacement platform adjust the precision higher, stability better, but also can prolong the life of mobile station.

Drawings

FIG. 1 is a schematic diagram of an overall structure of a displacement table with multiple degrees of freedom adjustment according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of a guide rail mechanism in a multi-degree-of-freedom adjustable displacement table according to an embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view of a rail mechanism along an extending direction of a linear bearing in a multi-degree-of-freedom adjustable displacement table according to an embodiment of the present invention;

FIG. 4 is a schematic cross-sectional view of a rail mechanism in a multi-degree-of-freedom adjustable displacement table according to an embodiment of the invention along a direction perpendicular to an extension direction of a linear bearing;

FIG. 5 is a schematic structural view of a first moving assembly in a rail mechanism of a multi-degree-of-freedom adjustable displacement table according to an embodiment of the present invention;

FIG. 6 is a schematic structural diagram of a second moving assembly in a rail mechanism of a multi-degree-of-freedom adjustable displacement table according to an embodiment of the present invention;

FIG. 7 is a schematic structural view of a fixing assembly in a rail mechanism of a multi-degree-of-freedom adjustable displacement table according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a force balancing module portion in a displacement table with multiple degrees of freedom adjustment according to an embodiment of the present invention.

Reference numerals:

a base 100; a rail mechanism 200; a securing assembly 210; a linear bearing 211; a first gas passage 2111; a throttle plate 212; a first restrictor 213; a first pneumatic fitting 214; a moving component 220; a first moving component 221; wedge rail 2211; a side plate 2212; a guide slide groove 2213; a second movement assembly 222; wedge bearing 2221; bearing housing 2222; ball pivot bearing 2223; an intake plate 223; a second pneumatic fitting 224; a second absorbent member 225; a first absorbent component 226; a grating scale 227; a grating scale reading head 228; a second restrictor 229; a carrier 300; a drive assembly 400; a magnetically balanced stator 410; balancing stator base 420; a magnetic balance mover 430; a balance mover mount 440; a linear stator 450; a linear mover 460; the mover coil connecting plate 470.

Detailed Description

In order that the above objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the invention, whereby the invention is not limited to the specific embodiments disclosed below.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present invention, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

Referring to fig. 1 to 8, an embodiment of the present invention provides a multi-degree-of-freedom adjustable displacement table, which includes a base 100, a plurality of guide rail mechanisms 200, a carrier 300 and a driving assembly 400, wherein the plurality of guide rail mechanisms 200 are arranged on the base 100 at intervals, each guide rail mechanism 200 includes a fixed assembly 210 and a movable assembly 220, the fixed assembly 210 is fixedly connected to the base 100, the fixed assembly and the movable assembly can be mutually limited, and the movable assembly 220 is slidably connected with the fixed assembly 210; the carrier 300 is rotatably connected with the moving assembly 220 in each guide rail mechanism 200; the driving end of the driving assembly 400 is connected to the moving assembly 220 to drive the moving assembly 220 to move relative to the fixed assembly 210, so as to realize the multi-degree-of-freedom adjustment of the carrier 300; the moving assembly 220 can be air-floated on the fixed assembly 210, so that when the moving assembly 220 moves relative to the fixed assembly 210, there is no friction between the moving assembly 220 and the fixed assembly 210.

The present solution provides a displacement table capable of adjusting multiple degrees of freedom, wherein a base 100 is used for supporting and connecting a rail mechanism 200 and a carrier 300. The fixed assembly 210 in the guide rail mechanism 200 is fixedly connected with the base 100, the movable assembly 220 is slidably connected with the fixed assembly 210, the carrier 300 is rotatably connected with the movable assembly 220, and when the driving assembly 400 drives the movable assembly 220 to move relative to the fixed assembly 210, the angle or position of the carrier 300 can be changed. And multiple degrees of freedom adjustment of the stage 300 is achieved by providing a plurality of spaced apart rail mechanisms 200 on the base 100 such that the movement assemblies 220 in the different rail mechanisms 200 are moved. And through setting up the movable assembly 220 to can be by the air supporting on fixed assembly 210 to when making movable assembly 220 remove relative fixed assembly 210, can not produce the friction between movable assembly 220 and the fixed assembly 210, thereby make the displacement adjustment precision of displacement platform higher, stability better, but also can prolong the life of mobile station.

It should be noted that the displacement stage with multiple degrees of freedom adjustment provided in the present application may be used in any scenario requiring multiple degrees of adjustment of the stage 300. In this embodiment, the above-mentioned displacement stage is described by taking an example of applying the above-mentioned displacement stage capable of adjusting multiple degrees of freedom to wafer inspection.

It is to be understood that the number of the rail mechanisms 200 is not limited, and may be set according to actual requirements. In the present embodiment, the number of the rail mechanisms 200 is three, and the three rail mechanisms 200 are uniformly distributed on the base 100. When the up-down displacement of the carrier 300 needs to be adjusted, the moving assemblies 220 in the three guide rail mechanisms 200 can be moved relative to the fixed assemblies 210 at the same time, so as to realize the up-and-down of the displacement table. When the angle of the stage 300 needs to be adjusted, the moving assembly 220 in one or both of the rail mechanisms 200 can be moved relative to the fixed assembly 210 to effect adjustment of the angle of the displacement stage.

As shown in fig. 2, 3 and 4, in one embodiment, the moving assembly 220 includes a first moving assembly 221 and a second moving assembly 222, the first moving assembly 221 is slidably connected to the fixed assembly 210, and the first moving assembly 221 is capable of moving in a first direction relative to the fixed assembly 210; the second moving assembly 222 is slidably connected with the first moving assembly 221 and is linked with the first moving assembly 221, the second moving assembly 222 can move along a second direction relative to the first moving assembly 221, and the second moving assembly 222 is rotatably connected with the carrier 300; wherein the first direction is perpendicular to the second direction.

In the present embodiment, by slidably connecting the first moving member 221 with the fixed member 210 such that the first moving member 221 can move along the first direction with respect to the fixed member 210, slidably connecting the second moving member 222 with the first moving member 221 such that the second moving member 222 can move along the second direction with respect to the first moving member 221, and disposing the second moving member 222 in a form of being interlocked with the first moving member 221. Such that the second moving assembly 222 can move in a second direction relative to the first assembly when the first moving assembly 221 moves in the first direction relative to the fixed assembly 210. Because the carrier 300 is rotatably connected with the second moving component 222, when the second moving component 222 moves relative to the first component, the carrier 300 can be driven to move along the second direction relative to the second moving component 222 and simultaneously rotate relative to the second moving component 222 under the action of the second moving component 222. Thus, the stage 300 can be moved in multiple degrees of freedom.

In this embodiment, the first direction may be a direction along a horizontal direction, and the second direction may be a direction along a vertical direction. That is, when the first moving component 221 moves in the horizontal plane, the first moving component 221 can drive the second component to move along the vertical direction, so that the up-and-down movement or the angle adjustment of the carrier 300 can be realized. In addition, it is understood that the first direction is any direction lying in a horizontal plane.

As shown in fig. 2, 3 and 4, in one embodiment, the fixing assembly 210 includes a linear bearing 211 fixedly coupled to the base 100, the linear bearing 211 extending along a first direction; the first moving unit 221 is provided with a guide chute 2213, the guide chute 2213 is in guide engagement with the linear bearing 211, and the air-bearing gas can flow into between the groove wall of the guide chute 2213 and the linear bearing 211, and an air film gap is formed between the groove wall of the guide chute 2213 and the linear bearing 211, so that the first moving unit 221 floats relative to the linear bearing 211 in a direction away from the linear bearing 211.

Specifically, the linear bearing 211 is fixedly connected to the base 100 through bolts, and the linear bearing 211 provides support for the first moving assembly 221 in the vertical direction and in the horizontal direction. In this embodiment, the linear bearing 211 cooperates with the first moving assembly 221 to guide movement of the first moving assembly 221 relative to the base 100 in a first direction. In the present embodiment, the first direction is a direction along the extending direction of the linear bearing 211. By arranging the guide slide groove 2213 on the first moving assembly 221 and guiding and matching the guide slide groove 2213 with the linear bearing 211, the movement of the first moving assembly 221 along the first direction relative to the linear bearing 211 is realized. By arranging the air-floating gas between the groove wall of the guide chute 2213 and the linear bearing 211, an air film gap can be formed between the groove wall of the guide chute 2213 and the linear bearing 211, so that when the first moving component 221 moves relative to the linear bearing 211, no friction exists between the first moving component 221 and the linear bearing 211, the displacement adjustment precision of the displacement table is higher, the stability is better, and the service life of the displacement table can be prolonged.

As shown in fig. 2, 3, 4 and 5, in particular, the first moving assembly 221 includes a wedge-shaped guide 2211 and two side plates 2212 disposed at intervals, the wedge-shaped guide 2211 includes a first surface disposed opposite to the linear bearing 211 and a second surface configured as a slope, and a distance between the first surface and the second surface is gradually reduced along a first direction; the wedge-shaped guide rail 2211 is disposed between the two side plates 2212 and is fixedly connected with the two side plates 2212, a guide chute 2213 is defined between the side surfaces of the two side plates 2212 and the first surface, the second moving assembly 222 is matched with the second surface, the wedge-shaped guide rail 2211 moves along the first direction relative to the linear bearing 211, and the second surface pushes the second moving assembly 222 to move along the second direction.

The side plates 2212 are arranged at two sides of the wedge-shaped guide 2211, so that the two side plates 2212 and the wedge-shaped guide 2211 are enclosed to define the guide chute 2213. When the air-bearing 211 and the groove wall of the guide groove 2213 are filled with the air-bearing, the side plates 2212 positioned at both sides of the wedge-shaped guide 2211 can block the air-bearing from leaking along both sides of the wedge-shaped guide 2211. Thereby facilitating the formation of a gas film gap between the first face of wedge rail 2211 and linear bearing 211, and between side plate 2212 and the sides of linear bearing 211, thereby enabling the gas to float wedge rail 2211 and both side plates 2212 upward, providing horizontal stiffness for movement of wedge rail 2211.

By providing the second face of wedge rail 2211 in the form of a ramp and providing the distance between the first face and the second face in a decreasing form along the first direction. Since the carrier 300 is rotatably connected to the plurality of second moving assemblies 222, the plurality of second moving assemblies 222 limit the carrier 300 in the first direction. Because the distance between the first surface and the second surface is changed, when the wedge-shaped guide rail 2211 moves along the first direction, the second surface can push the second moving component 222 to move along the second direction, so that the second moving component 222 can be driven to move by the movement of the first moving component 221, and the multi-degree-of-freedom adjustment of the carrier 300 can be realized. Specifically, the two side plates 2212 are respectively locked on two sides of the wedge-shaped guide rail 2211 by screws, and the air-floating gas can be compressed air.

As shown in fig. 2, 3, 4 and 5, further, the second moving assembly 222 includes a wedge bearing 2221, a bearing seat 2222 and a ball pivot bearing 2223, the wedge bearing 2221 includes a wedge surface, and the wedge surface is attached to the second surface; the bearing seat 2222 is fixedly connected to the side of the wedge bearing 2221 facing away from the wedge surface; the spherical hinge bearing 2223 is rotatably connected with the bearing seat 2222, and the spherical hinge bearing 2223 is fixedly connected with the carrier 300; when the wedge-shaped guide rail 2211 moves along the first direction relative to the linear bearing 211, the wedge-shaped bearing 2221 moves along the second direction under the action of the second surface, so that the spherical hinge bearing 2223 rotates relative to the bearing seat 2222.

By engaging the wedge surface of wedge bearing 2221 with the second face of wedge rail 2211, wedge bearing 2221 is urged to move in a second direction relative to base 100 by a change in the height of the second face. Since the bearing seat 2222 is fixedly connected with the wedge bearing 2221, the wedge bearing 2221 is driven to move along the second direction when moving along the second direction. Since the spherical hinge bearing 2223 is rotatably connected with the bearing seat 2222, the carrier 300 is fixedly connected with the spherical hinge bearing 2223, so that the portion of the carrier 300 connected with the spherical hinge bearing 2223 can move along the second direction and rotate relative to the bearing seat 2222. Thereby achieving adjustment of the position of the stage 300 in the second direction and adjustment of the angle.

Specifically, a countersunk hole is formed in a position, connected to the spherical hinge bearing 2223, on the carrier 300, where the spherical hinge bearing 2223 is fixedly connected to the carrier 300 through a pin, and the countersunk hole is used for accommodating a head of the pin, so that an object plane of the carrier 300 does not have obvious protrusions, so that an effective area of the object plane is increased.

The spherical hinge bearing 2223 is mounted on the bearing seat 2222 in an interference manner, and the spherical hinge bearing 2223 can be universally rotated on the bearing seat 2222 to match with decoupling of the carrier 300 during pitching leveling. The bearing housing 2222 is fixedly connected to the wedge bearing 2221 by bolts. By arranging the wedge bearing 2221 in the guide chute 2213, that is, between the two side plates 2212, when compressed air is filled between the wedge bearing 2221 and the side plates 2212, air film gaps can be formed between the wedge bearing 2221 and the side plates 2212 and between the wedge bearing 2221 and the second face of the wedge guide 2211, so that the wedge bearing 2221 moves relative to the wedge guide 2211 without friction, and the accuracy and reliability of the degree-of-freedom adjustment of the carrier 300 are improved.

As shown in fig. 2 and 5, in one embodiment, the displacement stage further includes a magnetic balance stator 410 and a magnetic balance mover 430, wherein the magnetic balance stator 410 is fixedly connected to the base 100; the magnetic balance mover 430 is fixedly connected to one of the side plates 2212 and is matched with the magnetic balance stator 410, and the magnetic balance mover 430 can provide thrust for the side plate 2212 along the first direction, and the thrust is opposite to the direction of the component force of the gravity applied to the wedge-shaped guide rail 2211 by the second moving assembly 222 along the first direction.

Specifically, a balancing stator base 420 is fixedly connected to the base 100, and the magnetic balancing stator 410 is fixedly connected to the balancing stator base 420; a balance rotor base 440 is fixedly connected to one side plate 2212, and a magnetic balance rotor 430 is fixedly connected to the balance rotor base 440. The magnetic balance mover 430 and the magnetic balance stator 410 interact to form a constant force spring system, and the magnetic balance mover 430 can apply a thrust force to the side plate 2212 in the axial direction of the magnetic balance mover 430. This thrust force can balance the component force of gravity received by wedge rail 2211 in the direction of gravity in the horizontal direction. So that the forces on the whole displacement table are balanced with each other in the whole system without external forces.

For example, as will be understood with reference to fig. 3 and 8, when a wafer to be tested is placed on the carrier 300, the gravity of the wafer applies a downward force to the wedge bearing 2221, and if the magnetic balance stator 410 and the magnetic balance mover 430 are not provided, the component of the force applied to the second face of the wedge bearing 2221 by the gravity of the wafer is horizontal to the right, and the wedge rail 2211 receives a leftward friction force of the wedge bearing 2221, and the wedge rail 2211 moves leftward under the action of this friction force. Accordingly, by attaching the magnetic balance mover 430 to the side plate 2212, the magnetic balance mover 430 applies a rightward force to the side plate 2212 to balance the leftward friction force applied to the second surface, so that the wedge-shaped guide 2211 remains balanced.

As shown in fig. 7, in one embodiment, the fixing assembly 210 further includes a throttle plate 212, a plurality of first throttles 213, and a first pneumatic connector 214, where the throttle plate 212 is covered on the linear bearing 211; a plurality of first throttles 213 are provided on the throttle plate 212; the first pneumatic connector 214 is arranged at one end of the linear bearing 211 and is used for being connected with an air source; the linear bearing 211 is provided with a first air passage 2111, and the first air passage 2111 is communicated with the first air connector 214 and is communicated with the first throttle 213, so that the air-bearing air flows from the first throttle 213 into the gap between the guide chute 2213 and the linear bearing 211.

The first pneumatic fitting 214 is connected to the compressed air, and when it is desired to move the compressed air from the first pneumatic fitting 214 to flow through the first air passage 2111, and from the first throttle 213 to flow between the linear bearing 211 and the side plate 2212, and between the linear bearing 211 and the wedge rail 2211, the wedge rail 2211 is provided with rigidity in the horizontal direction.

As shown in fig. 3 and 4, in one embodiment, the multi-degree of freedom adjustment displacement stage further includes at least one second absorbing member 225 fixedly connected to the base 100, where the second absorbing member 225 is capable of generating an absorbing force with the moving assembly to limit the moving assembly to move relative to the base 100. In the present embodiment, the second absorbing member 225 is a permanent magnet, and one permanent magnet is disposed below each of the two side plates 2212. The permanent magnet is fixedly connected with the base 100, the permanent magnet provides magnetic attraction force to attract the two side plates 2212, a pretightening force is provided for the wedge-shaped guide rail 2211 vertically, the pretightening force is matched with an air film formed between the upper surface of the linear bearing 211 and the first surface of the wedge-shaped guide rail 2211, the overall vertical rigidity of the wedge-shaped guide rail 2211 and the two side plates 2212 is improved, the external disturbance resistance is improved, and the working stability of the displacement table is improved.

As shown in fig. 2 and 6, in one embodiment, the moving assembly includes an air inlet plate 223 and a second actuating connector, the air inlet plate 223 is fixedly connected to the second moving assembly 222, and a second air passage is provided on the air inlet plate 223; the second pneumatic connector 224 is connected to the air inlet plate 223 and is communicated with the second air passage, and the second pneumatic connector 224 is also connected with an air source; the air-bearing gas can flow into the second air passage through the second pneumatic connector 224 and from the second air passage between the first moving assembly 221 and the second moving assembly 222 to create an air film gap between the first moving assembly 221 and the second moving assembly 222.

Specifically, the air inlet plate 223 is fixedly connected with a wedge bearing 2221, an air passage is also provided on the wedge bearing 2221, and a second restrictor 229 is also provided on the wedge bearing 2221. The compressed air rib second starting joint enters the second air passage of the air inlet plate 223 and flows out of the second restrictor 229 through the air passage in the wedge bearing 2221, and air film gaps are formed between the side plate 2212 and the side surface of the wedge bearing 2221 and between the bottom surface of the wedge bearing 2221 and the second surface of the wedge guide rail 2211, so that the wedge bearing 2221 is vertically upwards floated, and horizontal rigidity is provided for the movement of the wedge guide rail 2211.

As shown in fig. 4, further, the second moving assembly 222 further includes a first suction member 226 fixedly coupled to the wedge surface of the wedge bearing 2221; wherein, the second surface of the wedge-shaped guide rail 2211 is provided with a receiving groove, the first absorbing member 226 is slidably disposed in the receiving groove, and the first absorbing member 226 can generate an absorbing force with the wedge-shaped guide rail 2211 to limit the movement of the wedge-shaped bearing 2221 relative to the wedge-shaped guide rail 2211. Specifically, the second absorbing member 226 may be a permanent magnet, and is fixed at the lower end of the wedge bearing 2221 by a screw to provide a magnetic attraction force for the wedge bearing 2221 and the wedge rail 2211, and the magnetic attraction force is matched with a gas film formed between the wedge surface of the wedge bearing 2221 and the second surface of the wedge rail 2211, so as to improve the rigidity of the wedge bearing 2221 in the direction perpendicular to the wedge surface, increase the capability of resisting external disturbance, and improve the working stability of the displacement table. When it is desired to adjust the displacement of the stage 300, the air-bearing 2221 is floated by forming an air-film gap between the wedge surface of the wedge bearing 2221 and the second surface of the wedge rail 2211 against the above-mentioned magnetic attraction force. Since the ball pivot bearing 2223 is fixedly connected to the carrier 300, the wedge bearing 2221 is limited from being displaced in the horizontal direction, and when the wedge guide 2211 drives the two side plates 2212 to do horizontal linear motion on the linear bearing 211, the wedge bearing 2221 performs vertical lifting motion.

As shown in fig. 2, in one embodiment, the driving assembly 400 further includes a linear stator 450 and a linear mover 460, wherein the linear stator 450 is fixedly connected to the base 100; the linear mover 460 is fixedly connected with the moving assembly and cooperates with the linear stator 450 to drive the moving assembly to move relative to the linear stator 450. The linear stator 450 is fixedly connected to the base 100, the linear mover 460 is fixed to the side plate 2212 through the mover coil connecting plate 470, and the interaction between the linear mover 460 and the linear stator 450 provides a horizontal driving for the movement of the side plate 2212 relative to the linear bearing 211.

Further, in the present embodiment, a grating scale 227 is adhered to the side surface of the side plate 2212 facing the side of the balance mover, the grating scale reading head 228 is fixed on the base 100, and the grating scale 227 and the grating scale reading head 228 provide feedback and positioning in the horizontal direction for the movement of the wedge-shaped guide 2211. The displacement stage provided in this embodiment further includes an electrical mounting board mounted on the base 100 for mounting electrical components of the displacement stage.

According to the displacement table capable of being adjusted in multiple degrees of freedom, the plurality of guide rail mechanisms 200 are uniformly distributed on the base 100, and the carrier 300 is connected with the guide rail mechanisms 200; an electrical mounting board is mounted on the base 100 for mounting electrical components of the displacement stage, thereby ensuring accuracy and controllability of adjustment of the degree of freedom of the stage 300. The spherical hinge bearing 2223 is fixedly connected with the carrier 300 and is connected with the bearing seat 2222 in a universal rotation manner, so that the spherical hinge bearing 2223 can rotate with low friction in 360 degrees. When all the rail mechanisms 200 are moved up or down synchronously, the carrier 300 is moved up or down vertically; when one of the guide rail structures moves up and down and the rest remains fixed, the carrier 300 can be driven to pitch and adjust at a certain angle in the horizontal direction. The guide rail mechanism 200 is a friction-free air bearing composed of a linear bearing 211, a wedge-shaped guide rail 2211 and a wedge-shaped bearing 2221, and the movement of the wedge-shaped guide rail 2211 in the horizontal direction is converted into the vertical movement of the wedge-shaped bearing 2221; the wedge-shaped guide rail 2211 is driven to horizontally move through the mutual matching of the linear stator 450 and the linear rotor 460; the position is fed back through the grating ruler 227 to ensure the stability and positioning accuracy of the displacement adjustment of the carrier 300. The side surface of the wedge-shaped guide rail 2211 is provided with a friction-free constant force balancing module in the horizontal direction, so that the horizontal component force of the load decomposed to the wedge-shaped guide rail 2211 by gravity is overcome, and the control precision is improved. The displacement table capable of being adjusted in multiple degrees of freedom is compact in structure, capable of achieving active lifting and leveling functions, free of friction resistance, higher in positioning accuracy and stability and longer in service life, and adopts an air-float guide rail mode.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the invention, which are described in detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.

Claims (10)

1. The displacement platform capable of being adjusted in multiple degrees of freedom is characterized in that the displacement platform capable of being adjusted in multiple degrees of freedom comprises:

a base;

the guide rail mechanisms are arranged on the base at intervals, each guide rail mechanism comprises a fixed component and a movable component, the fixed components are fixedly connected to the base, and the fixed components and the movable components can be mutually limited;

the carrier is rotatably connected with the moving assembly in each guide rail mechanism;

the driving end of the driving assembly is connected with the moving assembly to drive the moving assembly to move relative to the fixed assembly so as to realize the multi-degree-of-freedom adjustment of the carrier;

the movable assembly can be air-floated on the fixed assembly, so that friction is avoided between the movable assembly and the fixed assembly when the movable assembly moves relative to the fixed assembly.

2. The multi-degree of freedom adjustable displacement table of claim 1 wherein the moving assembly comprises:

the first moving assembly is in sliding connection with the fixed assembly and can move along a first direction relative to the fixed assembly;

the second moving assembly is connected with the first moving assembly in a sliding manner and is linked with the first moving assembly, the second moving assembly can move along a second direction relative to the first moving assembly, and the second moving assembly is rotatably connected with the carrying platform;

wherein the first direction is perpendicular to the second direction.

3. The multi-degree of freedom adjustable displacement table of claim 2 wherein the stationary assembly includes a linear bearing fixedly attached to the base, the linear bearing extending along the first direction; the first moving assembly is provided with a guide chute, the guide chute is in guide fit with the linear bearing, air-float gas can flow into the space between the groove wall of the guide chute and the linear bearing, and an air film gap is formed between the groove wall of the guide chute and the linear bearing, so that the first moving assembly floats relative to the linear bearing in a direction away from the linear bearing.

4. A multi-degree of freedom adjustable displacement table of claim 3 wherein the first moving assembly comprises:

the wedge-shaped guide rail comprises a first surface and a second surface which are oppositely arranged, the first surface is opposite to the linear bearing, the second surface is configured as an inclined surface, and the distance between the first surface and the second surface is gradually reduced along the first direction;

the wedge-shaped guide rail is arranged between the two side plates and fixedly connected with the two side plates, and the side surfaces of the two side plates and the first surface are enclosed to define the guide chute;

the second moving assembly is matched with the second face, the wedge-shaped guide rail moves along the first direction relative to the linear bearing, and the second face pushes the second moving assembly to move along the second direction.

5. The multi-degree of freedom adjustable displacement table of claim 4 wherein the second moving assembly comprises:

the wedge-shaped bearing comprises a wedge-shaped surface, and the wedge-shaped surface is attached to the second surface;

the bearing seat is fixedly connected to the side surface of the wedge-shaped bearing, which is away from the wedge-shaped surface;

the spherical hinge bearing is rotationally connected with the bearing seat and fixedly connected with the carrier;

when the wedge-shaped guide rail moves along the first direction relative to the linear bearing, the wedge-shaped bearing moves along the second direction under the action of the second surface, so that the spherical hinge bearing rotates relative to the bearing seat.

6. The multiple degree of freedom adjustable displacement stage of claim 5 wherein the second moving assembly further comprises:

the first absorption part is fixedly connected with the wedge-shaped surface of the wedge-shaped bearing;

the second surface of the wedge-shaped guide rail is provided with an accommodating groove, the first absorption part is slidably arranged in the accommodating groove, and absorption force can be generated between the first absorption part and the wedge-shaped guide rail so as to limit the wedge-shaped bearing to move relative to the wedge-shaped guide rail.

7. The multi-degree of freedom adjustable displacement table of claim 4 further comprising:

the magnetic balance stator is fixedly connected to the base;

the magnetic balance rotor is fixedly connected to one of the side plates and matched with the magnetic balance stator, the magnetic balance rotor can provide thrust for the side plates along the first direction, and the thrust is opposite to the direction of the component of the gravity applied to the wedge-shaped guide rail by the second moving assembly along the first direction.

8. A multi-degree of freedom adjustable displacement table of claim 3 wherein the securing assembly further comprises:

the throttle plate is covered on the linear bearing;

a plurality of first throttles provided on the throttle plate;

the first pneumatic connector is arranged at one end of the linear bearing and is used for being connected with an air source;

the linear bearing is provided with a first air passage, and the first air passage is communicated with the first air connector and the first throttle, so that the air-float gas flows into a gap between the guide chute and the linear bearing from the first throttle.

9. The multi-degree of freedom adjustable displacement table of claim 2 wherein the moving assembly comprises:

the air inlet plate is fixedly connected with the second moving assembly, and a second air passage is arranged on the air inlet plate;

the second pneumatic connector is connected with the air inlet plate and communicated with the second air passage, and the second pneumatic connector is also connected with an air source;

the air-bearing gas can flow into the second air passage through the second pneumatic connector and flow from the second air passage to between the first moving assembly and the second moving assembly to create an air film gap between the first moving assembly and the second moving assembly.

10. The multi-degree of freedom adjustable displacement table of any one of claims 1-8, further comprising:

the second absorbing part is fixedly connected to the base and can generate absorbing force with the moving assembly so as to limit the moving assembly to move relative to the base.