CN103062290B - Electromagnetic damping vibration isolator with coplace air flotation orthogonal decoupling and rolling knuckle bearing angle decoupling - Google Patents

Abstract

The electromagnetic damping vibration isolator with coplanar air bearing orthogonal decoupling and rolling joint bearing angle decoupling belongs to the field of precision vibration isolation technology. For lubrication and support, electromagnetic dampers are used to attenuate vibration energy and improve positioning stability. The degree of freedom of horizontal linear motion between the upper mounting plate and the lower mounting plate is decoupled through coplanar orthogonal air bearing guide rails, and the degree of freedom of angular motion is passed through Rolling joint bearings are decoupled, voice coil motors, displacement sensors, limit switches, controllers, and drivers form a position closed-loop feedback control system to accurately control the relative positions of the upper and lower mounting plates; the invention has three-dimensional zero stiffness, high The decoupling characteristics of positioning accuracy, linear motion degree of freedom and angular motion degree of freedom can effectively solve the problem of high-performance vibration isolation in ultra-precision measuring instruments and processing equipment, especially in step-and-scan lithography machines.

Description

Electromagnetic Damping Vibration Isolator Based on Coplanar Air Bearing Orthogonal Decoupling and Rolling Joint Bearing Angle Decoupling

technical field

The invention belongs to the technical field of precision vibration isolation, and mainly relates to an electromagnetic damping vibration isolator for coplanar air bearing orthogonal decoupling and rolling joint bearing angle decoupling.

Background technique

With the continuous improvement of ultra-precision machining and measurement accuracy, environmental vibration has become an important factor restricting the improvement of the accuracy and performance of ultra-precision machining equipment and measuring instruments. In particular, the ultra-large-scale integrated circuit processing equipment represented by the step-scan lithography machine is extremely technically intensive and complex, and the key technical indicators have reached the limit of the existing technology, representing the highest level of ultra-precision processing equipment. Precision vibration isolation has become the core key technology in this type of equipment; the line width of the step-and-scan lithography machine has reached 22nm and below, the positioning accuracy and overlay accuracy of silicon wafers have reached several nanometers, and the movement speed of the workpiece table has reached 1m/s Above, the acceleration of the workpiece table reaches dozens of times of the acceleration of gravity, which poses a new challenge to the existing vibration isolation technology. First of all, the lithography machine needs to provide an "ultra-quiet" working environment for the metrology system and the lithography objective lens, and at the same time needs to drive the workpiece table to move at high speed and high acceleration, which poses extremely strict requirements on the vibration isolation performance of the vibration isolation system. It is required that the natural frequencies in the three directions must be below 1Hz; secondly, the relative position between the various components of the lithography machine, such as the distance between the lithography objective lens and the surface of the silicon wafer, has very strict requirements and is in a position closed loop Under the control of the feedback control system, the relative position accuracy between the upper and lower mounting plates of the vibration isolator is required to reach the order of 10 μm, and the positioning accuracy of the traditional vibration isolator is far from meeting the requirements.

According to the vibration isolation theory, the natural frequency of a passive vibration isolator is proportional to the stiffness and inversely proportional to the load mass. Therefore, under the premise of a certain load mass, reducing the stiffness of the vibration isolator is to reduce the natural frequency and improve low frequency and ultra-low frequency vibration isolation. efficient way to perform. Vibration isolators in the form of traditional air springs have an inherent contradiction between static load capacity and stiffness. At the same time, they are constrained by factors such as material properties and structural stiffness. It is very difficult to further reduce their stiffness, especially the horizontal stiffness. In response to this problem, the researchers introduced the "pendulum" structure into the air spring vibration isolator to achieve the purpose of reducing the horizontal stiffness of the vibration isolator (1. Nikon Corporation. Vibration Isolator With Low Lateral Stiffness. US Patent Publication No.: US20040065517A1 : 2. U.S.Philips Corporation. Positioning Device with a Force Actuator System for Compensating Center-of-gravity Displacements, and Lithographic Device Provided with Such A Positioning Device. U.S. Patent No.: US005844664A). This method can reduce the horizontal stiffness of the air spring isolator to a certain extent and improve its low-frequency vibration isolation performance. The problems of this method are as follows: 1) Due to the constraints of material properties and structural stiffness, the amplitude of vertical and horizontal stiffness reduction of the vibration isolator is limited; 2) The vertical and horizontal positioning accuracy of the air spring vibration isolator is very poor, It cannot meet the requirements of the photolithography process; 3) To achieve a lower horizontal stiffness requires a larger pendulum length, resulting in excessive height of the vibration isolator, prone to string-membrane resonance, and poor stability.

Through the analysis of the technical scheme of the existing air spring isolator, it can be seen that the existing air spring isolator is difficult to meet the requirements of ultra-low stiffness and high positioning accuracy of the lithography machine. The German IDE company proposed a vibration isolator technology solution that abandons the traditional rubber air spring (1. Integrated Dynamics Engineering GmbH. Isolatorgeometrie Eines Schwingungsisolationssystem. European Patent No.: EP1803965A2; 2. Integrated Dynamics Engineering GmbH. Schwingungsisolationssystem Mit Pneumatischemil. European Patent No.: filter Tiefpass EP 1803970A2; 3. Integrated Dynamics Engineering GmbH. Air Bearing with Consideration of High-Frequency Resonances. US Patent Publication No.: US20080193061A1). The solution uses vertical and horizontal air bearings to decouple and isolate vibrations in all directions, which can achieve extremely low stiffness and natural frequency. The problems of this solution are: 1) In the disclosed technical solution, the vibration isolator cannot achieve precise positioning; 2) In the patent EP1803965A2, there is no degree of freedom of angular movement around the horizontal axis between the upper and lower mounting plates. The angular stiffness and natural frequency are very high; patents EP1803970A2 and US20080193061A1 use rubber blocks to provide angular freedom of rotation around the horizontal axis for the upper and lower mounting plates, but due to the high angular stiffness of the rubber blocks, the angular freedom of motion cannot be effectively achieved Degree of freedom decoupling, the friction between the components of the angular motion degree of freedom decoupling mechanism introduces additional stiffness, which restricts the vibration isolation performance.

Netherlands ASML company also proposed a similar vibration isolator technical scheme (1. U.S.Philips Corp, ASM Lithography B.V. Pneumatic Support Device with A Controlled Gas Supply, and Lithographic Device Provided with Such A Support Device. U.S. Patent No.: US006144442A; 2 .Koninklijke Philips ElectronicsN.V.，ASM Lithography B.V.LithographicPneumatic Support Device with Controlled Gas Supply.国际专利公开号：WO99/22272；3.ASML Netherlands B.V.Support Device，LithographicApparatus，and Device Manufacturing Method Employing A Supporting Device，and A PositionControl System Arranged for Use in A Supporting Device.美国专利号：US007084956B2；4.ASML Netherlands B.V.Support Device，Lithographic Apparatus，and Device ManufacturingMethod Employing A Supporting Device and A Position Control System Arranged for Use in ASupporting Device.欧洲专利号：EP1486825A1 ). In patent US006144442A and WO99/22272, closed-loop feedback control is performed on the air source pressure to achieve the purpose of improving the stability and performance of the vibration isolator; in patent US007084956B2 and EP1486825A1, a vibration sensor is installed on the upper mounting plate, and a reference vibration system is introduced at the same time. The vibration isolation performance of the vibration isolator is improved through the control algorithm. However, the proposed technical solution still does not solve the problem of decoupling the precise positioning of the vibration isolator and the angular motion degrees of freedom of the upper and lower mounting plates.

Contents of the invention

The purpose of the present invention is to provide a coplanar air conditioning system for the urgent requirements of ultra-precision measuring instruments and processing equipment, especially ultra-large-scale integrated circuit processing equipment such as step-scan lithography machines, for vibration isolators with low natural frequency and high positioning accuracy. Electromagnetic damping vibration isolator with floating orthogonal decoupling and rolling joint bearing angle decoupling. The vibration isolator has approximately zero stiffness and extremely low natural frequency in three dimensions. The degree of freedom of motion and angular motion are decoupled, so as to effectively solve the problem of precision vibration isolation in ultra-precision measuring instruments and processing equipment, especially in step-and-scan lithography machines.

Technical solution of the present invention is:

An electromagnetic damping vibration isolator with coplanar air bearing orthogonal decoupling and rolling joint bearing angle decoupling, which consists of an upper mounting plate, a lower mounting plate, a clean compressed air source, a gas pipe, and a vibration isolator body. The vibration isolator body Installed between the upper mounting plate and the lower mounting plate, the clean compressed air source is connected to the main body of the vibration isolator through the air pipe, in the structure of the main body of the vibration isolator, the lower surface of the sleeve and the lower The floating surface is lubricated and supported, the piston cylinder is installed in the sleeve with the reverse buckle, and the sleeve is lubricated and supported by the radial bearing cylindrical air bearing surface, the rolling joint bearing is installed between the piston cylinder and the upper mounting plate, the sleeve and the X-direction air The floating guide rail is lubricated and guided by the air-floating surface of the X-direction rail, the X-direction air-floating guide rail and the lower mounting plate are lubricated and supported by the Z-direction bearing air-floating surface, the Y-direction air-floating guide rail and the lower mounting plate are rigidly connected, and the two sides of the X-direction air-floating guide rail The end and the Y-direction air-bearing guide rail are lubricated and guided by the air-bearing surface of the Y-direction guide rail; the Z-direction voice coil motor, Z-direction displacement sensor, and Z-direction limit switch are installed between the piston barrel and the sleeve; the X-direction voice coil motor, X-direction The displacement sensor in the X direction, the limit switch in the X direction and the voice coil motor in the Y direction, the displacement sensor in the Y direction and the limit switch in the Y direction are installed between the sleeve and the lower mounting plate; the driving force direction of the Z direction voice coil motor is the vertical direction , the driving force directions of the X-direction voice coil motor and the Y-direction voice coil motor are in the horizontal plane and perpendicular to each other, and the direction of the action line of the displacement sensor in the X, Y, and Z directions and the limit switch in the X, Y, and Z directions is the same as that of the X, Y, and Z directions. The direction of the driving force of the Z-direction voice coil motor is consistent; X, Y, and Z-direction displacement sensors and X, Y, and Z-direction limit switches are respectively connected to the signal input terminals of the controller, and the signal output terminals of the controller are connected to the signal input terminals of the driver. The signal output terminals of the driver are respectively connected to the X, Y, and Z direction voice coil motors; the X direction permanent magnets are installed on the side wall of the upper surface of the lower mounting plate along the X direction of the voice coil motor driving force direction to form an X direction electromagnetic damper. Y-direction permanent magnets are installed on the side wall of the upper surface of the mounting plate along the Y-direction of the driving force of the voice coil motor to form a Y-direction electromagnetic damper, and Z-direction permanent magnets are installed on the side wall of the outer cylindrical surface of the piston cylinder along the Z-direction of the driving force of the voice coil motor. Z-direction electromagnetic damper, the magnetic pole directions of the X and Y permanent magnets are perpendicular to the upper surface of the lower mounting plate, and the N and S poles are arranged alternately, the magnetic pole directions of the Z-direction permanent magnets are perpendicular to the outer cylindrical surface of the piston barrel, and N , The S poles are alternately arranged, the piston barrel and the lower mounting plate are made of ferromagnetic materials, and the sleeve is made of non-magnetic and good conductor materials.

A gas pressure sensor is arranged in the piston barrel, an air inlet and a solenoid valve are arranged on the piston barrel, the gas pressure sensor is connected to the signal input end of the controller, the signal output end of the controller is connected to the signal input end of the driver, and the driver The signal output terminal is connected with the solenoid valve.

The voice coil motors in the X, Y and Z directions are cylindrical voice coil motors or flat voice coil motors.

The X-direction air-floating guide rail and the Y-direction air-floating guide rail have a single guide rail structure or a double guide rail structure.

The X, Y, and Z direction displacement sensors are grating scales, magnetic scales, capacitive scales or linear potentiometers.

The X-, Y-, and Z-direction limit switches are mechanical limit switches, Hall-type limit switches or photoelectric limit switches.

The gas pressure in the piston barrel is 0.1MPa-0.8MPa.

The air film thickness of the axial bearing plane air bearing surface, the radial bearing cylindrical air bearing surface, the X guiding guide air bearing surface, the Y guiding guide air bearing surface and the Z bearing air bearing surface is 10 μm to 20 μm.

The diameters of the cylindrical air bearing surface throttle hole on the piston barrel and the plane air bearing surface throttle hole 24 on the sleeve 6 are φ0.1mm˜φ1mm.

The technical innovation of the present invention and the good effect that produce are:

(1) The present invention abandons the traditional vibration isolator technical scheme based on elastic elements/mechanisms, and adopts the axial bearing flat air bearing surface and the radial bearing cylindrical air bearing surface to decouple and isolate the horizontal and vertical vibrations respectively. There is no friction on the floating surface, and the stiffness is approximately zero, so that the vibration isolator can obtain approximately zero stiffness characteristics and outstanding ultra-low frequency vibration isolation performance, which solves the problem that the existing technology is limited by structural stiffness and material properties, and the stiffness is difficult to further reduce. Stiffness and stability Sexual incompatibility. This is one of the innovative points that the present invention is different from the prior art.

(2) The present invention adopts displacement sensors, limit switches, controllers, drivers, and voice coil motors to form a closed-loop feedback control system for vertical and horizontal positions to precisely control the relative position between the upper and lower mounting plates , the positioning accuracy can reach 10 μm level and above, which can effectively solve the problems of low positioning accuracy, positioning accuracy, stiffness, and vibration isolation performance of existing technical solutions. This is the second innovative point that the present invention is different from the prior art.

(3) The present invention uses coplanar orthogonal air-floating guide rails and rolling joint bearings to decouple the degrees of freedom of linear motion and angular motion between the upper and lower mounting plates of the vibration isolator, and the friction between the air-floating guide rails and rolling joint bearings The wear and tear and the additional stiffness introduced can be ignored, which can effectively solve the problems that the existing technical solution using elastic body decoupling introduces a large additional stiffness and severely restricts the natural frequency. This is the third innovative point that the present invention is different from the prior art.

(4) The present invention adopts a gas pressure sensor, a solenoid valve, a controller, a driver, etc. to form a pressure closed-loop feedback control system to precisely control the gas pressure in the sleeve to keep it constant, and to balance the gravity and balance the axial load of the vibration isolator. Compensation, under the action of the air bearing surface of the radial bearing cylinder, the piston cylinder carrying the load gravity can slide up and down freely along the sleeve with zero stiffness, so as to achieve the ideal gravity balance and zero stiffness vibration isolation effect. This is the fourth innovative point that the present invention is different from the prior art.

(5) The present invention uses an active actuator to actively control the relative position between the upper and lower mounting plates, and the parameters of the vibration isolator can be adjusted in real time according to the characteristics of the vibration-isolated object and the change of the working environment, so as to adapt to different working conditions and have the advantages of Better flexibility, adaptability and stability. This is the fifth innovative point that the present invention is different from the prior art.

(6) The present invention adopts an electromagnetic damper based on an alternating magnetic pole permanent magnet array, which can be well integrated with a vibration isolator. The electromagnetic damper has a relatively ideal linear damping characteristic, which can effectively attenuate vibration energy and reduce motor drive. The positioning overshoot provides the stability of the isolator. This is the sixth innovation point that the present invention is different from the prior art.

Description of drawings

Figure 1 is a schematic structural diagram of the electromagnetic damping vibration isolator with coplanar air bearing orthogonal decoupling and rolling joint bearing angle decoupling after the upper mounting plate is removed;

Fig. 2 is a schematic cross-sectional structure diagram of an electromagnetic damping vibration isolator with coplanar air bearing orthogonal decoupling and rolling joint bearing angle decoupling;

Fig. 3 is a schematic diagram of an axial bearing plane air bearing surface, a radial bearing cylindrical air bearing surface, an X-direction rail air bearing surface and a Z bearing air bearing surface;

Fig. 4 is a schematic diagram of the air bearing surface of the Y guide rail;

Fig. 5 is a schematic diagram of the sleeve structure;

Fig. 6 is a structural schematic diagram of a ball cage of a single-row ball rolling joint bearing;

Fig. 7 is a structural schematic diagram of a rolling joint bearing covered with balls;

Fig. 8 is a block diagram of the control structure of the electromagnetic damping vibration isolator with coplanar air bearing orthogonal decoupling and rolling joint bearing angle decoupling;

Fig. 9 is a schematic diagram of an orifice on the plane air bearing surface on the sleeve;

Fig. 10 is the schematic diagram of the orifice on the cylindrical air bearing surface on the piston barrel;

Fig. 11 is a schematic cross-sectional structure diagram of a Z-direction electromagnetic damper;

Fig. 12 is a schematic diagram of a partial cross-sectional structure of an electromagnetic damper in X and Y directions;

Fig. 13 is an A-A sectional view of an installation method of the Z-direction permanent magnet on the side wall of the outer cylindrical surface of the piston barrel;

Fig. 14 is an A-A cross-sectional view of another installation method of the Z-direction permanent magnet on the outer cylindrical side wall of the piston barrel;

Fig. 15 is a schematic diagram of an installation method of the X and Y direction permanent magnets on the upper side wall of the lower mounting plate;

Fig. 16 is a schematic diagram of another installation method of the X and Y direction permanent magnets on the upper side wall of the lower mounting plate.

Part number description in the figure: 1 upper mounting plate, 2 lower mounting plate, 3 clean compressed air source, 4 vibration isolator main body, 5 piston cylinder, 6 sleeve, 7 rolling joint bearing, 7a bearing body, 7b ball cage, 7c ball, 7d bearing seat, 8X direction voice coil motor, 8a X direction motor iron yoke, 8b X direction motor magnetic steel, 8c X direction motor coil skeleton, 8d X direction motor coil, 9Y direction voice coil motor, 10Z direction voice coil Motor, 10a Z-direction motor iron yoke, 10b Z-direction motor magnetic steel, 10c Z-direction motor coil skeleton, 10d Z-direction motor coil, 10e Z-direction motor transition piece, 11X-direction displacement sensor, 11a X-direction grating reading head transition piece, 11b X-direction grating reading head, 11c X-direction glass grating ruler, 12Y-direction displacement sensor, 13Z-direction displacement sensor, 13a Z-direction grating reading head transition piece, 13b Z-direction grating reading head, 13c Z-direction glass grating ruler, 14X-direction limit Position switch, 14a X-direction limit block, 14b X-direction Hall switch, 14c X-direction limit switch transition piece, 14d X-direction limit block transition piece, 15Y-direction limit switch, 16Z-direction limit switch, 16a Z-direction Limit block, 16b Hall switch in Z direction, 16c Transition piece for limit switch in Z direction, 17 Gas pressure sensor, 18 Solenoid valve, 19 Controller, 20 Driver, 21 Axial bearing plane air bearing surface, 22 Radial bearing cylindrical air bearing Floating surface, 23 air inlets, 24 planar air bearing surface throttle holes, 25 cylindrical air bearing surface throttle holes, 26 air pipes, 29X air bearing guide rails, 30Y air bearing guide rails, 31X guide rail air bearing surfaces, 32Y guide rail air bearing surface, 33Z direction bearing air bearing surface, 40X direction electromagnetic damper, 40A X direction permanent magnet, 41Y direction electromagnetic damper, 41A Y direction permanent magnet, 42Z direction electromagnetic damper, 42AZ direction permanent magnet.

Detailed ways

Specific embodiments of the present invention are given below in conjunction with the accompanying drawings.

An electromagnetic damping vibration isolator with coplanar air bearing orthogonal decoupling and rolling joint bearing angle decoupling, consisting of an upper mounting plate 1, a lower mounting plate 2, a clean compressed air source 3, an air pipe 26 and a vibration isolator body 4 The vibration isolator main body 4 is installed between the upper mounting plate 1 and the lower mounting plate 2, and the clean compressed air source 3 is connected to the vibration isolator main body 4 through the air pipe 26. In the structure of the vibration isolator main body 4, the sleeve 6 The lower surface and the lower mounting plate 2 are lubricated and supported by the axial bearing flat air bearing surface 21, the piston barrel 5 is installed in the sleeve 6 with an undercut, and are lubricated and supported with the sleeve 6 by the radial bearing cylindrical air bearing surface 22, rolling The joint bearing 7 is installed between the piston barrel 5 and the upper mounting plate 1, the sleeve 6 and the X-direction air bearing guide rail 29 are lubricated and guided through the X-direction guide air bearing surface 31, and the X-direction air bearing guide rail 29 and the lower mounting plate 2 pass through the Z Lubricate and support the bearing air-floating surface 33, the Y-direction air-floating guide rail 30 is rigidly connected to the lower mounting plate 2, the two ends of the X-direction air-floating guide rail 29 and the Y-direction air-floating guide rail 30 are lubricated and guided by the Y-direction air-floating surface 32; The Z direction voice coil motor 10, the Z direction displacement sensor 13, and the Z direction limit switch 16 are installed between the piston barrel 5 and the sleeve 6, and the X direction voice coil motor 8, the X direction displacement sensor 11, and the X direction limit switch 14 The Y-direction voice coil motor 9, the Y-direction displacement sensor 12, and the Y-direction limit switch 15 are installed between the sleeve 6 and the lower mounting plate 2; the driving force direction of the Z-direction voice coil motor 10 is the vertical direction, and the X-direction The driving force directions of the voice coil motor 8 and the Y direction voice coil motor 9 are in the horizontal plane and are perpendicular to each other, X, Y, Z direction displacement sensors 11, 12, 13 and X, Y, Z direction limit switches 14, 15, 16 The direction of the action line is consistent with the direction of the driving force of the X, Y, and Z direction voice coil motors 8, 9, and 10; the X, Y, and Z direction displacement sensors 11, 12, 13 and the X, Y, and Z direction limit switches 14, 15,16 are respectively connected with the signal input end of controller 19, and the signal output end of controller 19 is connected with the signal input end of driver 20, and the signal output end of driver 20 is respectively connected with X, Y, Z direction voice coil motor 8,9 , 10 connection; the X-direction permanent magnet 40A is installed on the side wall of the upper surface of the lower mounting plate 2 along the driving force direction of the X-direction voice coil motor 8 to form the X-direction electromagnetic damper 40, and the upper surface side wall of the lower mounting plate 2 is along the Y-direction of the voice coil motor 9 Install a Y-direction permanent magnet 41A in the driving force direction to form a Y-direction electromagnetic damper 41, install a Z-direction permanent magnet 42A on the outer cylindrical side wall of the piston barrel 5 along the Z-direction voice coil motor 10 driving force direction to form a Z-direction electromagnetic damper 42 The magnetic pole directions of the X and Y permanent magnets 40A and 41A are perpendicular to the upper surface of the lower mounting plate 2, and the N and S poles are alternately arranged, and the magnetic pole direction of the Z permanent magnet 42A is perpendicular to the outer cylindrical surface of the piston barrel 5, and The N and S poles are alternately arranged, the piston barrel 5 and the lower mounting plate 2 are made of ferromagnetic materials, and the sleeve 6 is made of non-magnetic and good conductor materials.

X, Y, and Z direction displacement sensors 11, 12, and 13 measure the displacement output by X, Y, and Z direction voice coil motors 8, 9, and 10, and X, Y, and Z direction limit switches 14, 15, and 16 are for X , Y, and Z direction voice coil motors 8,9,10 movement stroke limit; 16 feedback signals to control the X, Y, Z direction voice coil motors 8, 9, 10 to accurately control the relative position between the upper and lower mounting plates 1, 2.

Gas pressure sensor 17 is provided in described piston barrel 5, and air inlet 23 and solenoid valve 18 are provided on piston barrel 5, and gas pressure sensor 17 is connected with the signal input end of controller 19, and the signal output end of controller 19 is connected with The signal input end of the driver 20 is connected, and the signal output end of the driver 20 is connected with the solenoid valve 18 .

The voice coil motors 8, 9 and 10 in the X, Y and Z directions are cylindrical voice coil motors or flat voice coil motors.

The X-direction air-floating guide rail 29 and the Y-direction air-floating guide rail 30 have a single guide rail structure or a double guide rail structure.

The X, Y, Z direction displacement sensors 11, 12, 13 are grating scales, magnetic scales, capacitive scales or linear potentiometers.

The X, Y, and Z limit switches 14, 15, and 16 are mechanical limit switches, Hall-type limit switches or photoelectric limit switches.

The gas pressure in the piston barrel 5 is 0.1MPa-0.8MPa.

The air film thickness of the axial bearing plane air bearing surface 21 , the radial bearing cylindrical air bearing surface 22 , the X guide rail air bearing surface 31 , the Y guide guide air bearing surface 32 and the Z bearing air bearing surface 33 is 10 μm to 20 μm.

The diameters of the cylindrical air bearing surface throttle hole 25 on the piston barrel 5 and the plane air bearing surface throttle hole 24 on the sleeve 6 are φ0.1mm˜φ1mm.

An embodiment of the present invention is given below in conjunction with FIG. 1 to FIG. 5 and FIG. 8 . In this embodiment, when the vibration isolator is working, the lower mounting plate 2 is rigidly connected to the foundation, the base of the instrument or the foundation frame, etc., and the upper mounting plate 1 is rigidly connected to the load or platform. Voice coil motors 8, 9, and 10 in X, Y, and Z directions all adopt cylindrical voice coil motors. Taking the X-direction voice coil motor 8 as an example, it is mainly composed of an X-direction motor iron yoke 8a, an X-direction motor magnet 8b, an X-direction motor coil skeleton 8c, and an X-direction motor coil 8d. The X-direction motor iron yoke 8a and the X-direction motor bobbin 8c are cylindrical, the X-direction motor magnet 8b is cylindrical, and the X-direction motor coil 8d is wound on the X-direction motor coil bobbin 8c. The X-direction motor iron yoke 8a and the X-direction motor magnetic steel 8b constitute the motor stator, and the X-direction motor coil skeleton 8c and the X-direction motor coil 8d constitute the motor mover. In the Z-direction voice coil motor 10, the Z-direction motor transition piece 10e provides the installation structure of the Z-direction motor coil skeleton 10c. When the motor is working, a current is passed through the coil. According to the electromagnetic theory, the energized coil will be affected by the Lorentz force in the magnetic field. By controlling the magnitude and direction of the current, the magnitude and direction of the motor output driving force can be controlled.

X, Y, and Z direction displacement sensors 11, 12, 13 adopt grating rulers. Taking the Z-direction displacement sensor 13 as an example, it mainly includes a Z-direction grating reading head transition piece 13a, a Z-direction grating reading head 13b, and a Z-direction glass scale 13c. The Z-direction grating readhead transition piece 13a provides a mounting structure for the Z-direction grating readhead 13b. When the grating ruler is working, the Z-direction grating reading head 13b can detect the relative displacement between it and the Z-direction glass grating ruler 13c, and send it to the controller 19 through the signal wire.

X, Y, Z direction limit switches 14, 15, 16 adopt Hall type limit switches. Taking the Z-direction limit switch 16 as an example, it mainly includes components such as a Z-direction limit block 16a, a Z-direction Hall switch 16b, and a Z-direction limit switch transition piece 16c. The two Z-direction Hall switches 16b are installed back to back, and the two Z-direction limit blocks 16a are made of metal materials, and are installed opposite to the sensitive end of the Z-direction Hall switch 16b. The Z-direction limit switch transition piece 16c provides a mounting structure for the Z-direction Hall switch 16b. When the limit switch is working, when the Z-direction Hall switch 16b is close to the Z-direction limit block 16a, the Z-direction Hall switch 16b gives a limit signal and sends it to the controller 19 through the signal wire.

In this implementation, the Z-direction voice coil motor 10 , the Z-direction displacement sensor 13 and the Z-direction limit switch 16 are all installed between the piston cylinder 5 and the sleeve 6 and inside the piston cylinder 5 .

The load bearing of the vibration isolator is realized in the following manner: the clean compressed air source 3 delivers clean compressed air to the piston cylinder 5 through the air pipe 26 , the electromagnetic valve 18 and the air inlet 23 . The controller 19 controls the opening of the solenoid valve 18 according to the feedback signal from the gas pressure sensor 17, and adjusts the gas flow rate input into the piston cylinder 5, thereby adjusting the pressure of the clean compressed air in the piston cylinder 5, so that the clean compressed air acts on the piston cylinder. The upward force of 5 is balanced with the gravity of the load, the piston cylinder 5 and other parts loaded on the piston cylinder 5, so as to realize the ideal gravity compensation and zero-stiffness vibration isolation effect.

In this embodiment, the pressure of clean compressed air in the piston cylinder 5 is 0.4MPa, and the effective radius of the lower surface of the piston cylinder 5 is 100mm, so the mass carried by a single vibration isolator is: m=p×πr ² /g≈1282kg, Where p is the gas pressure, p=0.4MPa, r is the effective radius of the lower surface of the piston cylinder 5, r=100mm, g is the acceleration of gravity, g=9.8m/s ² .

An embodiment of the single-row ball rolling joint bearing is given below with reference to Fig. 2 and Fig. 6 . In this embodiment, the main components of the rolling joint bearing 7 include a bearing body 7a, a ball cage 7b, a ball 7c and a bearing seat 7d, the balls 7c are evenly distributed in a single row around the axis, and the ball cage 7b is at the position corresponding to the ball 7c It has a round hole, and the position of the ball 7c is held by the ball cage 7b.

Figure 7 shows an embodiment of a full-ball rolling joint bearing. In this embodiment, the balls 7c are evenly distributed on the action surfaces of the bearing body 7a and the bearing seat 7d, the ball cage 7b is in the form of a spherical surface, and has a round hole at the position corresponding to the ball 7c, and the position of the ball 7c is determined by the ball cage 7b to keep.

Figure 9 shows an embodiment of the orifice on the plane air bearing surface of the sleeve. In this embodiment, eight orifice holes 24 on the plane air-floating surface are uniformly distributed around the center of the circle on the lower surface of the sleeve 6 along the circumferential direction, with a diameter of φ0.2mm.

Figure 10 shows an embodiment of the orifice on the cylindrical air bearing surface on the piston cylinder. In this embodiment, two rows of orifice holes 25 on the cylindrical air-floating surface are evenly distributed along the circumferential direction on the side wall of the piston cylinder 5, and the number of orifice holes 25 on each row of cylindrical air-floating surface is 8, with a diameter of φ0.2mm.

An embodiment of the Z-direction electromagnetic damper is given below in conjunction with FIG. 11 and FIG. 13 . In this embodiment, the vibration isolator has two Z-direction electromagnetic dampers 42, which are composed of a Z-direction permanent magnet 42A array installed on the side wall of the outer cylindrical surface of the piston cylinder 5. The piston cylinder 5 is made of No. 45 steel material, which has a high The magnetic permeability is high, and the sleeve 6 is made of copper material, which is non-magnetic and has high electrical conductivity. The Z-direction permanent magnet 42A is bar-shaped, arranged along the driving force direction of the Z-direction voice coil motor 10 , that is, the axial direction of the piston cylinder 5 , the magnetic pole direction is perpendicular to the outer cylindrical surface of the piston cylinder 5 , and N and S poles are alternately arranged. When the sleeve 6 and the piston cylinder 5 move relative to each other in the Z direction, the sleeve 6 cuts the lines of magnetic force to generate eddy current and damping force, and the Z direction damping force is proportional to the relative movement speed of the sleeve 6 and the piston cylinder 5 in the Z direction, and Consistent with the direction of the driving force of the Z-direction voice coil motor 10, the purpose of consuming vibration energy and improving positioning stability is achieved.

Fig. 11 and Fig. 14 show another embodiment of the Z electromagnetic damper. In this embodiment, the vibration isolator has four Z-direction electromagnetic dampers 42 , which are composed of an array of Z-direction permanent magnets 42A installed on the side wall of the outer cylindrical surface of the piston barrel 5 . The Z-direction permanent magnet 42A is bar-shaped, arranged along the driving force direction of the Z-direction voice coil motor 10 , that is, the axial direction of the piston cylinder 5 , the magnetic pole direction is perpendicular to the outer cylindrical surface of the piston cylinder 5 , and N and S poles are alternately arranged.

An embodiment of the X and Y direction electromagnetic dampers is given below in conjunction with Fig. 12 and Fig. 15 . In this embodiment, the vibration isolator has two X-direction electromagnetic dampers 40 and two Y-direction electromagnetic dampers 41, which are respectively composed of arrays of X- and Y-direction permanent magnets 40A and 41A installed on the side walls of the upper surface of the lower mounting plate 2 , The lower mounting plate 2 is made of No. 45 steel material with high magnetic permeability, and the sleeve 6 is made of red copper material, which is non-magnetic and has high electrical conductivity. The permanent magnets 40A and 41A in the X and Y directions are elongated, arranged along the driving force directions of the voice coil motors 8 and 9 in the X and Y directions respectively, the direction of the magnetic poles is perpendicular to the upper surface of the lower mounting plate 2, and the N and S poles alternate layout. When the sleeve 6 and the lower mounting plate 2 move relative to each other, the sleeve 6 cuts the lines of magnetic force to generate eddy currents and damping forces, and the damping force in the X and Y directions is related to the relative movement of the sleeve 6 and the lower mounting plate 2 in the X and Y directions. The speed is directly proportional, and the direction is consistent with the driving force directions of the X and Y direction voice coil motors 8 and 9, so as to achieve the purpose of consuming vibration energy and improving positioning stability.

Fig. 12 and Fig. 16 show another embodiment of the X and Y direction electromagnetic dampers. In this embodiment, the vibration isolator has an X-direction electromagnetic damper 40 and a Y-direction electromagnetic damper 41 , which are respectively composed of arrays of X- and Y-direction permanent magnets 40A and 41A installed on the sidewall of the upper surface of the lower mounting plate 2 . The permanent magnets 40A and 41A in the X and Y directions are elongated, arranged along the driving force directions of the voice coil motors 8 and 9 in the X and Y directions respectively, the direction of the magnetic poles is perpendicular to the upper surface of the lower mounting plate 2, and the N and S poles alternate layout.

Claims (9)

1. the electromagnetic damping vibration isolator of a coplanar air supporting crossing decoupling and the decoupling zero of rolling joint shaft bearing angle, by upper mounting plate (1), lower installation board (2), clean compressed gas source (3), tracheae (26) and vibration isolator main body (4) composition, vibration isolator main body (4) is arranged between upper mounting plate (1) and lower installation board (2), clean compressed gas source (3) is connected with vibration isolator main body (4) by tracheae (26), it is characterized in that: in the structure of described vibration isolator main body (4), the lower surface of sleeve (6) and lower installation board (2) are lubricated by axial carrying plane air bearing surface (21) and support, piston cylinder (5) back-off is arranged in sleeve (6), and lubricate with sleeve (6) by the radial cylinder air bearing surface (22) that carries and support, rolling joint shaft bearing (7) is arranged between piston cylinder (5) and upper mounting plate (1), sleeve (6) is lubricated and guiding by X direction guiding rail air bearing surface (31) to air-float guide rail (29) with X, X is lubricated and support to air-float guide rail (29) and lower installation board (2) by Z-direction bearing air-float face (33), Y-direction air-float guide rail (30) and lower installation board (2) are rigidly connected, X is lubricated and guiding to the two ends of air-float guide rail (29) and Y-direction air-float guide rail (30) by Y-direction guide rail air bearing surface (32), Z-direction voice coil motor (10), Z-direction displacement transducer (13), Z-direction limit switch (16) are arranged between piston cylinder (5) and sleeve (6), and X is arranged on sleeve (6) and lower installation board (2) between to displacement transducer (11), X to limit switch (14) and Y-direction voice coil motor (9), Y-direction displacement transducer (12), Y-direction limit switch (15) to voice coil motor (8), X, the driving force direction of Z-direction voice coil motor (10) is vertical direction, X is mutually vertical in horizontal plane to the driving force direction of voice coil motor (8) and Y-direction voice coil motor (9), and X, Y, Z-direction displacement transducer (11,12,13) are consistent with the driving force direction of X, Y, Z-direction voice coil motor (8,9,10) with the line of action direction of X, Y, Z-direction limit switch (14,15,16), X, Y, Z-direction displacement transducer (11,12,13) are connected with the signal input part of controller (19) respectively with X, Y, Z-direction limit switch (14,15,16), the signal output part of controller (19) is connected with the signal input part of driver (20), and the signal output part of driver (20) is connected with X, Y, Z-direction voice coil motor (8,9,10) respectively, along X to voice coil motor (8) driving force direction, X is installed at lower installation board (2) upper surface sidewall and forms X to electromagnetic damper (40) to permanent magnet (40A), along Y-direction voice coil motor (9) driving force direction, Y-direction permanent magnet (41A) is installed at lower installation board (2) upper surface sidewall and forms Y-direction electromagnetic damper (41), along Z-direction voice coil motor (10) driving force direction, Z-direction permanent magnet (42A) is installed at piston cylinder (5) external cylindrical surface sidewall and forms Z-direction electromagnetic damper (42), X, Y-direction permanent magnet (40A, pole orientation 41A) is perpendicular to the upper surface of lower installation board (2), and N, S pole is alternately arranged, the pole orientation of Z-direction permanent magnet (42A) is perpendicular to the external cylindrical surface of piston cylinder (5), and N, S pole is alternately arranged, piston cylinder (5) and lower installation board (2) adopt ferromagnetic material, sleeve (6) adopts non-magnetic good conductor material.

2. the electromagnetic damping vibration isolator of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of rolling joint shaft bearing angle, it is characterized in that: in described piston cylinder (5), be provided with gas pressure sensor (17), piston cylinder (5) is provided with suction port (23) and solenoid valve (18), gas pressure sensor (17) is connected with the signal input part of controller (19), the signal output part of controller (19) is connected with the signal input part of driver (20), the signal output part of driver (20) is connected with solenoid valve (18).

3. the electromagnetic damping vibration isolator of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of rolling joint shaft bearing angle, is characterized in that: described X, Y, Z-direction voice coil motor (8,9,10) are cylinder type voice coil motor or plate voice coil motor.

4. the electromagnetic damping vibration isolator of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of rolling joint shaft bearing angle, is characterized in that: described X is single rail structure or two guide rail structure to air-float guide rail (29) and Y-direction air-float guide rail (30).

5. the electromagnetic damping vibration isolator of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of rolling joint shaft bearing angle, is characterized in that: described X, Y, Z-direction displacement transducer (11,12,13) are grating scale, magnetic railings ruler, appearance grid chi or linear potentiometer.

6. the electromagnetic damping vibration isolator of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of rolling joint shaft bearing angle, is characterized in that: described X, Y, Z-direction limit switch (14,15,16) are mechanical type limit switch, Hall-type limit switch or photoelectric limit switch.

7. the electromagnetic damping vibration isolator of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of rolling joint shaft bearing angle, is characterized in that: described piston cylinder (5) interior gas pressure is 0.1MPa ~ 0.8MPa.

8. the electromagnetic damping vibration isolator of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of rolling joint shaft bearing angle, is characterized in that: the air-film thickness in described axial carrying plane air bearing surface (21), radial carrying cylinder air bearing surface (22), X direction guiding rail air bearing surface (31), Y-direction guide rail air bearing surface (32) and Z-direction bearing air-float face (33) is 10 μm ~ 20 μm.

9. the electromagnetic damping vibration isolator of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of rolling joint shaft bearing angle, is characterized in that: the diameter of the cylinder air bearing surface throttle orifice (25) on described piston cylinder (5) and the plane air bearing surface throttle orifice (24) on sleeve (6) is φ 0.1mm ~ φ 1mm.