CN103062302A - Coplane air floatation orthogonal decoupling and air floatation ball bearing angle decoupling magnetic levitation vibration isolator - Google Patents

Abstract

The maglev vibration isolator with coplanar air bearing orthogonal decoupling and air bearing ball bearing angle decoupling belongs to the field of precision vibration isolation technology. The thrust bearing and the static pressure air bearing surface are lubricated and supported. The degree of freedom of horizontal linear motion between the upper mounting plate and the lower mounting plate is decoupled by coplanar orthogonal air bearing guide rails. The degree of freedom of angular motion between the two is decoupled by air The floating ball bearing is decoupled, and the voice coil motor, displacement sensor, limit switch, controller, and driver form a position closed-loop feedback control system to accurately control the relative position 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

Maglev vibration isolator with coplanar air bearing orthogonal decoupling and air bearing angular decoupling

technical field

The invention belongs to the technical field of precision vibration isolation, and mainly relates to a magnetic suspension vibration isolator for coplanar air bearing orthogonal decoupling and air bearing ball 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 APositioning 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 EP1803970A2; 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 High degree of decoupling, there is friction between the components of the decoupling mechanism, which introduces a large additional stiffness, which restricts the natural frequency and low frequency 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.Lithographic Pneumatic 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 effectively solve the problem of precise positioning of the vibration isolator and decoupling of 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. The maglev vibration isolator is a maglev vibration isolator with orthogonal decoupling and air bearing angle decoupling. The vibration isolator has approximately zero stiffness and extremely low natural frequency in three dimensions. The upper and lower mounting plates can be precisely positioned and three-dimensional straight 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.

The purpose of the present invention is achieved like this:

A magnetic suspension vibration isolator with coplanar air bearing orthogonal decoupling and air bearing ball bearing angle decoupling, which consists of an upper mounting plate, a lower mounting plate, a clean compressed air source, a gas pipe, and a main body of the vibration isolator. The main body of the vibration isolator is 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. Support, the piston cylinder is installed in the sleeve under the buckle, and the sleeve is lubricated and supported by the radial bearing cylinder air bearing surface, the air bearing ball bearing is installed between the piston cylinder and the upper mounting plate, the sleeve and the X-direction air bearing guide rail The air bearing surface of the X-direction guide is lubricated and guided, the X-direction air-flotation guide rail and the lower mounting plate are lubricated and supported by the Z-direction air bearing surface, the Y-direction air-flotation guide rail is rigidly connected with the lower mounting plate, and the two ends of the X-direction air-flotation guide rail are connected to the lower mounting plate. The Y-direction air bearing guide rail is 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 and the X-direction displacement The sensor, the X-direction limit switch, the Y-direction voice coil motor, the Y-direction displacement sensor, and the Y-direction limit switch 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, and the X direction The direction of the driving force of the voice coil motor and the Y direction voice coil motor is in the horizontal plane and perpendicular to each other, and the direction of the action line of the X, Y, Z direction displacement sensor and the X, Y, Z direction limit switch The driving force of the voice coil motor is in the same direction; the X, Y, Z direction displacement sensor and the X, Y, Z direction limit switch are respectively connected to the signal input end of the controller, and the signal output end of the controller is connected to the signal input end of the driver , the signal output terminals of the driver are respectively connected to the X, Y, and Z direction voice coil motors.

A gas pressure sensor is arranged inside 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, and the signal output end of the driver is connected to the solenoid valve.

The configuration of the magnetic levitation thrust bearing is that permanent magnets are arranged on the side wall of the bottom surface of the sleeve, and electromagnetic coils are installed on the upper surface side wall of the lower mounting plate. The thickness of the magnetic levitation gap is 0.01 mm to 1 mm.

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 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 magnetic levitation thrust bearings and radially loaded cylindrical air bearing surfaces to decouple and isolate horizontal and vertical vibrations respectively. Magnetic levitation thrust bearings and The air bearing surface has no friction, no wear, 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. Stiffness and stability can not balance the problem. 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 to decouple the degree of freedom of horizontal linear motion between the upper and lower mounting plates of the vibration isolator. The air-floating guide rails have no friction and wear, do not introduce additional stiffness, and have a decoupling effect Good, it can make the vibration isolator achieve high positioning accuracy and vibration isolation performance; the air-floating ball bearing is used to decouple the degree of freedom of angular motion, the air-floating ball bearing has no friction and wear, and does not introduce additional angular stiffness, which can effectively solve the existing The technical solution of elastic body decoupling introduces a large additional stiffness, which restricts the natural frequency and low frequency vibration isolation performance and other issues. 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 gas pressure in the piston cylinder, 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 that Adapt to different working conditions, with good flexibility, adaptability and stability. This is the fifth innovative point that the present invention is different from the prior art.

Description of drawings

Figure 1 is a schematic structural diagram of a magnetic suspension vibration isolator with coplanar air bearing orthogonal decoupling and air bearing ball bearing angle decoupling after the upper mounting plate is removed;

Figure 2 is a schematic cross-sectional structure diagram of a magnetic suspension vibration isolator with coplanar air bearing orthogonal decoupling and air bearing ball bearing angle decoupling;

Figure 3 is a schematic diagram of the maglev gap, the radial bearing cylindrical air bearing surface, the X-direction guide air bearing surface, the Z bearing air bearing surface and the spherical 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 block diagram of the control structure of the maglev vibration isolator with coplanar air bearing orthogonal decoupling and air bearing ball bearing angle decoupling;

Fig. 7 is a schematic diagram of a cylindrical air-floating surface throttle hole and a spherical air-floating surface throttle hole on the piston barrel.

Part number description in the picture: 1 upper mounting plate, 2 lower mounting plate, 3 clean compressed air source, 4 main body of vibration isolator, 5 piston cylinder, 6 sleeve, 7 air bearing, 8 X direction voice coil motor, 8a X Direction motor iron yoke, 8b X direction motor magnet, 8c X direction motor coil bobbin, 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 magnet , 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 scale, 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 scale, 14X direction limit 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 Z-direction Hall switch, 16c Z-direction limit switch Position switch transition piece, 17 Gas pressure sensor, 18 Solenoid valve, 19 Controller, 20 Driver, 21 Maglev gap, 22 Radial bearing cylindrical air bearing surface, 23 Air inlet, 24 Maglev thrust bearing, 24a Permanent magnet, 24b Electromagnetic coil , 25 cylindrical air bearing surface orifice, 26 air pipes, 27 spherical air bearing surface, 28 spherical air bearing surface orifice, 29X air bearing guide rail, 30Y air bearing guide rail, 31X air bearing guide rail, 32Y guide air bearing air bearing surface, 33Z to the air bearing surface.

Detailed ways

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

A magnetic suspension vibration isolator with coplanar air bearing orthogonal decoupling and air bearing ball 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 main body of the vibration isolator 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. The structure of the vibration isolator main body 4 is: a sleeve 6 The lower surface and the lower mounting plate 2 are lubricated and supported by the magnetic thrust bearing 24, the piston barrel 5 is installed in the sleeve 6 with an undercut, and is lubricated and supported with the sleeve 6 through the radial bearing cylindrical air bearing surface 22, and the air bearing 7 Installed between the piston cylinder 5 and the upper mounting plate 1, the sleeve 6 and the X-direction air-floating guide rail 29 are lubricated and guided by the X-direction air-floating surface 31, and the X-direction air-floating guide rail 29 and the lower mounting plate 2 are carried by the Z-direction The air bearing surface 33 is lubricated and supported, the Y direction air bearing guide rail 30 is rigidly connected with the lower mounting plate 2, the two ends of the X direction air bearing guide rail 29 and the Y direction air bearing guide rail 30 are lubricated and guided by the Y direction guide air bearing surface 32; The voice coil motor 10, the Z direction displacement sensor 13 and the Z direction limit switch 16 are installed between the piston cylinder 5 and the sleeve 6, and the X direction voice coil motor 8, the X direction displacement sensor 11, the X direction limit switch 14 and the Y direction Voice coil motor 9, Y-direction displacement sensor 12, and 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 voice coil The driving force directions of the motor 8 and the Y-direction voice coil motor 9 are in the horizontal plane and are perpendicular to each other. The direction of the line is consistent with the direction of the driving force of the X, Y, and Z direction voice coil motors 8, 9, 10; the X, Y, and Z direction displacement sensors 11, 12, 13 and the X, Y, and Z direction limit switches 14, 15, 16 is 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 to voice coil motor 8,9,10 connect.

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.

A gas pressure sensor 17 is provided in the piston barrel 5, an air inlet 23 and a solenoid valve 18 are arranged on the piston barrel 5, the gas pressure sensor 17 is connected with the signal input end of the controller 19, and the signal output end of the driver 20 is connected with the electromagnetic valve. Valve 18 is connected.

The magnetic levitation thrust bearing 24 is arranged in such a way that a permanent magnet 24a is arranged on the side wall of the bottom surface of the sleeve 6, and an electromagnetic coil 24b is installed on the upper surface side wall of the lower mounting plate oppositely, and the thickness of the magnetic levitation gap 21 is 0.01 mm to 1 mm.

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.

An embodiment of the present invention is given below with reference to FIG. 1 to FIG. 6 . 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.

The installation method of the air-floating ball bearing 7 in this embodiment is as follows: the lower surface of the air-floating ball bearing 7 is installed on the piston barrel 5, and is lubricated and supported by the spherical air-floating surface 27, and the upper surface of the air-floating ball bearing 7 is installed on the upper surface. Board 1 is rigidly connected.

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 embodiment, 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 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/m ² .

Fig. 7 shows an embodiment of the orifice on the cylindrical air-floating surface and the orifice on the spherical air-floating surface on the piston barrel. 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. On the concave spherical surface of the upper surface of the piston cylinder 5, eight spherical air-floating surface throttle holes 28 are evenly distributed around the center of the circle along the circumferential direction, and the diameter is φ0.2mm.

Claims (8)

1. the floating vibration isolator of the magnetic of a coplanar air supporting crossing decoupling and the decoupling zero of air-floating ball bearing angle, by upper mounting plate (1), lower installation board (2), clean compressed gas source (3), tracheae (26) and vibration isolator main body (4) form, vibration isolator main body (4) is installed between upper mounting plate (1) and the 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) be lubricated and support by the floating thrust-bearing (24) of magnetic, piston cylinder (5) back-off is installed in the sleeve (6), and with sleeve (6) by radially carry cylinder air bearing surface (22) lubricated with support, air-floating ball bearing (7) is installed between piston cylinder (5) and the upper mounting plate (1), sleeve (6) lubricates and guiding by X-direction guide rail air bearing surface (31) with X-direction air-float guide rail (29), X-direction air-float guide rail (29) and lower installation board (2) lubricated and support by Z-direction bearing air-float face (33), Y-direction air-float guide rail (30) is rigidly connected with lower installation board (2), and the two ends of X-direction air-float guide rail (29) and Y-direction air-float guide rail (30) be lubricated and guiding by Y-direction guide rail air bearing surface (32); Z-direction voice coil motor (10), Z-direction displacement transducer (13) and Z-direction limit switch (16) are installed between piston cylinder (5) and the sleeve (6), X-direction voice coil motor (8), X-direction displacement transducer (11), X-direction limit switch (14) and Y-direction voice coil motor (9), Y-direction displacement transducer (12), Y-direction limit switch (15) is installed between sleeve (6) and the lower installation board (2), the driving force direction of Z-direction voice coil motor (10) is vertical direction, the driving force direction of X-direction voice coil motor (8) and Y-direction voice coil motor (9) in horizontal plane and mutually vertical, X, Y, Z-direction displacement transducer (11,12,13) and X, Y, Z-direction limit switch (14,15,16) line of action direction and X, Y, Z-direction voice coil motor (8,9,10) driving force direction is consistent; X, Y, Z-direction displacement transducer (11,12,13) are connected Y, Z-direction limit switch (14,15,16) and are connected with the signal input part of controller (19) respectively with X, 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.

2. the magnetic of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of air-floating ball bearing angle floats vibration isolator, it is characterized in that: be provided with gas pressure sensor (17) in the described piston cylinder (5), 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), and the signal output part of driver (20) is connected with solenoid valve (18).

3. the magnetic of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of air-floating ball bearing angle floats vibration isolator, it is characterized in that: the configuration mode that described magnetic floats thrust-bearing (24) is to be provided with permanent magnet (24a) at sleeve (6) bottom surface sidewall, at the relatively equipped electromagnetic coil (24b) of lower installation board upper surface sidewall, it is 0.01mm～1mm that magnetic floats gap (21) thickness.

4. the magnetic of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of air-floating ball bearing angle floats vibration isolator, and it 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.

5. the magnetic of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of air-floating ball bearing angle floats vibration isolator, and it is characterized in that: described X-direction air-float guide rail (29) and Y-direction air-float guide rail (30) are single rail structure or two guide rail structure.

6. the magnetic of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of air-floating ball bearing angle floats vibration isolator, it 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.

7. the magnetic of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of air-floating ball bearing angle floats vibration isolator, and it 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.

8. the magnetic of coplanar air supporting crossing decoupling according to claim 1 and the decoupling zero of air-floating ball bearing angle floats vibration isolator, and it is characterized in that: the interior gas pressure of described piston cylinder (5) is 0.1MPa～0.8MPa.

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