CN-121978870-A - Ultra-precise triaxial air floating platform

Abstract

The invention discloses an ultra-precise triaxial air floating platform, which adopts a collaborative design of a vacuum pre-compressed air floating guide rail and a porous throttling air floating bearing, combines nanoscale feedback of a high-precision linear grating ruler with closed-loop control system adjustment, realizes the repeated precision of an XY plane nanoscale position and the lifting precision within +/-1 nm of a Z axis, eliminates mechanical friction by a full-air floating non-contact structure, compensates processing and assembly errors by elastic buffering and self-adaptive adjustment capability of an air film, effectively reduces vibration transmission and motion resistance by matching with multi-frequency-band vibration isolation of an air floating vibration isolation device, improves the running stability and service life of equipment, reduces maintenance cost, realizes frictionless lifting and sub-nanoscale position control by matching with U-shaped guide rail guidance by adopting a combination of friction-free cylinder balance gravity and linear motor drive, and improves track smoothness and dynamic response speed by matching with the X/Y axis double-motor linkage and the air floating bearing, and meets the dynamic requirements of complex linkage processing or measurement.

Inventors

• ZHANG XIAFENG
• GUO YAWEN

Assignees

• 广州科技贸易职业学院

Dates

Publication Date

20260505

Application Date

20260210

Claims (10)

1. 1. The ultra-precise triaxial air floating platform comprises a base (1), an air floating guide rail structure (2), a workbench (3), a cross beam (4), an air floating vibration isolation device (5), an air supply system (6) and an air floating bearing (7), and is characterized in that: the air-float guide rail structure (2), the workbench (3) and the cross beam (4) are all arranged above the base (1); The air bearing (7) is arranged on the side surface of the workbench (3) contacted with the cross beam (4); The air-floating guide rail structure (2) comprises an XY plane air-floating platform (21) and a Z-axis structure (22), the XY plane air-floating platform (21) adopts a vacuum pre-compressed air-floating guide rail as a support and guide, the Z-axis structure (22) is arranged on the cross beam (4), and the Z-axis structure (22) comprises a friction-free air cylinder (221), a U-shaped guide rail (222), a slide carriage (223) and a position feedback element (224); the air floatation vibration isolation device (5) is arranged at the lower end of the base (1); The air supply system (6) comprises an air source unit (61), a filtering device (62), a pressure regulating valve group (63) and a connecting pipeline (64), wherein the air source unit (61) is used for providing high-pressure clean air, the filtering device (62) is used for removing micron-sized impurities and condensed water, the pressure regulating valve group (63) is used for accurately stabilizing the air pressure to a working pressure range required by each air floatation part, and the connecting pipeline (64) is respectively connected to the XY plane air floatation platform (21), the air floatation bearing (7) and the frictionless air cylinder (221) for continuously conveying clean and stable working air for each air floatation part.
2. 2. An ultra-precise triaxial air bearing platform according to claim 1, characterized in that the air bearing (7) is a porous vacuum pre-pressed air bearing.
3. 3. The ultra-precise triaxial air bearing platform according to claim 1, characterized in that the Z-axis structure (22) further includes a linear motor (225), the linear motor (225) being connected to the slide (223).
4. 4. The ultra-precise triaxial air bearing platform according to claim 1, characterized in that the Y-axis of the XY plane air bearing platform (21) is of an H-type layout structure, the bottom surface of the Y-axis supports the weight by the air bearing (7), and the air bearing (7) is also arranged on both side surfaces of the Y-axis, which are in contact with the base (1).
5. 5. An ultra-precise triaxial air bearing platform according to claim 1, characterized in that the position feedback element (224) is a high-precision linear grating scale.
6. 6. An ultra-precise triaxial air bearing platform according to claim 1, characterized in that the air bearing vibration isolation means (5) comprises an air spring for isolating low frequency vibrations and a damper for suppressing vibration amplitude at resonance.
7. 7. An ultra-precise triaxial air bearing platform according to claim 1, characterized in that the filtering means (62) comprise a primary filter, a precision filter and an oil mist removing filter connected in sequence.
8. 8. An ultra-precise triaxial air bearing platform according to claim 1, characterized in that the X-axis in the XY plane air bearing platform (21) is driven by a motor and the Y-axis is driven by a double motor.
9. 9. The ultra-precise triaxial air floating platform according to claim 1, characterized in that a plurality of organ covers (8) are further arranged at the upper end of the workbench (3), and the organ covers (8) are arranged between the workbench (3) and the cross beam (4).
10. 10. The ultra-precise triaxial air bearing platform according to claim 1, further comprising a control system (9), wherein the control system (9) is electrically connected with the position feedback element (224), the linear motor (225), the X-axis and Y-axis driving motors and the pressure regulating valve group (63) and is used for receiving real-time position signals transmitted by the position feedback element (224), and adjusting the rotation speed and rotation direction of the linear motor (225) and the driving motors of each axis through a closed-loop control algorithm, so as to precisely control the gas pressure output of the pressure regulating valve group (63).

Description

Ultra-precise triaxial air floating platform Technical Field The invention relates to the technical field of precision motion platforms, in particular to an ultra-precision triaxial air floating platform. Background The precision motion platform is used as a core component in various precision automation equipment and generally has a nanoscale positioning capability, so that the precision motion platform is widely applied to the fields of integrated circuits, chip manufacturing, precision machining, measurement and the like. Along with the increasing demand of industry upgrading for high-end equipment, precision motion platforms with large travel, high precision, high speed, high stability and other performances are gradually favored by the industry. The dynamic performance of the platform is directly affected by the precise motion platform driving technology and the guide rail structure, and in order to realize the high-speed, high-precision and other indexes of the platform, the air-bearing and direct-driving technology is generated. The air-float guide rail is used as a platform support and a motion guide, so that the friction influence can be eliminated, and the high-speed and high-precision positioning control can be easily realized. In order to overcome the defects of short stroke, friction, response lag and the like caused by the combination of the rotating motor and the ball screw to realize linear motion, the linear motor is adopted to directly drive the workbench to move, so that a transmission link is eliminated, the inertia of a system is reduced, the linear motor has no abrasion, low noise and extensible working stroke in the motion process, and the requirements of large stroke, high speed, high acceleration and the like can be met. Although the use of an air-float guide rail and a linear motor for directly driving a load to move brings great advantages, higher requirements on a motor control mode are required to achieve high-performance targets such as quick response, accurate positioning and the like. The precise air-floating motion platform not only requires the capability of precise positioning, but also requires high dynamic performance, and how to improve the tracking performance of the platform in the motion process is an important ring for realizing precise motion. Therefore, the invention provides an ultra-precise triaxial air floating platform. Disclosure of Invention Aiming at the defects of the prior art, the invention provides an ultra-precise triaxial air floating platform to solve the problems. The ultra-precise triaxial air floating platform comprises a base, an air floating guide rail structure, a workbench, a cross beam, an air floating vibration isolation device, an air supply system and an air floating bearing; the air-float guide rail structure, the workbench and the cross beam are all arranged above the base; the air bearing is arranged on the side surface of the workbench, which is contacted with the cross beam; the air-floating guide rail structure comprises an XY plane air-floating platform and a Z-axis structure, the XY plane air-floating platform adopts a vacuum pre-compressed air-floating guide rail as a support and guide, the Z-axis structure is arranged on the cross beam, and the Z-axis structure comprises a friction-free air cylinder, a U-shaped guide rail, a slide carriage and a position feedback element; The air floatation vibration isolation device is arranged at the lower end of the base; The air supply system comprises an air source unit, a filtering device, a pressure regulating valve group and a connecting pipeline, wherein the air source unit is used for providing high-pressure clean air, the filtering device is used for removing micron-sized impurities and condensed water, the pressure regulating valve group is used for accurately stabilizing the air pressure to the working pressure range required by each air floatation component, and the connecting pipeline is respectively connected to the XY plane air floatation platform, the air floatation bearing and the frictionless air cylinder and is used for continuously conveying clean and stable working air for each air floatation component. Preferably, the air bearing uses a porous vacuum preloading air bearing. Preferably, the Z-axis structure further comprises a linear motor, and the linear motor is connected with the slide carriage. Preferably, a Y-axis in the XY-plane air-floating platform is in an H-shaped layout structure, the bottom surface of the Y-axis supports the weight through the air-floating bearing, and the air-floating bearing is also arranged on two side surfaces of the Y-axis, which are in contact with the base. Preferably, the position feedback element uses a high precision linear grating scale. Preferably, the air-floating vibration isolation device comprises an air spring and a damper, wherein the air spring is used for isolating low-frequency vibration, and the damper is used for suppressi