High-precision gas bearing static characteristic test board and test method thereof

Abstract

The invention relates to the field of detection devices, and discloses a high-precision gas bearing static characteristic test board, which comprises an optical base, a gas bearing static characteristic test board and a gas bearing static characteristic test board, the detection table is arranged on the optical base; the suspension bracket is arranged on the optical base; the detection air cylinder is arranged on the suspension bracket, and the detection air cylinder is located right above the detection table; the air floating ball hinge is arranged at the driving end of the detection air cylinder; the pressure sensor is arranged at the bottom of the air floating ball hinge; the upper floating bearing plate is arranged at the bottom of the pressure sensor, and the upper floating bearing plate is used for being pressed on the detection table; and the laser interference measurement assembly is arranged between the lower surface of the floating bearing plate and the upper surface of the optical base and is used for measuring the displacement and inclination of the lower surface of the floating bearing plate. According to the invention, the partial static characteristics of the gas bearing can be accurately evaluated.

Description

Technical Field

[0001] The invention relates to the field of detection devices, and in particular to a high-precision gas bearing static characteristic test bench and a test method thereof. Background Art

[0002] Gas bearings have the advantages of high speed, high precision, and no friction. They are increasingly used in industry, and are mainly used in ultra-high speed, ultra-precision motion and other technical fields. In order to ensure high precision and stability of motion, it is necessary to test the static characteristics of gas bearings. Considering that the thickness of the gas film of gas bearings is generally in the micron level, the measurement accuracy is very high. At present, the existing bearing measurement devices have large errors and low accuracy, and it is difficult to accurately obtain the static characteristics of gas bearings. Therefore, it is necessary to further improve the detection accuracy. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0004] The present invention provides a high-precision gas bearing static characteristic test bench, which comprises: an optical base; a detection bench, which is arranged on the optical base and is used to place a gas bearing workpiece; a suspension bracket, which is arranged on the optical base; a detection cylinder, which is arranged on the suspension bracket and is located directly above the detection bench; an air float joint, which is arranged at the driving end of the detection cylinder; a pressure sensor, which is arranged at the bottom of the air float joint; a floating bearing plate, which is arranged at the bottom of the pressure sensor and is used to be pressed on the detection bench; a laser interferometer measurement component, which is arranged between the lower surface of the floating bearing plate and the upper surface of the optical base, and the laser interferometer measurement component is provided with at least two groups, and the at least two groups of laser interferometer measurement components are distributed on both sides of the detection bench, and are used to measure the displacement and inclination of the lower surface of the floating bearing plate.

[0005] Therefore, the present invention drives the floating bearing plate to press against the gas bearing workpiece on the detection table through the detection cylinder arranged on the suspension bracket, obtains the buoyancy value of the gas bearing through the pressure sensor, and realizes full adaptability by utilizing the frictionless characteristic of the air float ball joint, thereby ensuring that the air film thickness between the upper surface of the gas bearing and the lower surface of the floating bearing plate is the same. At the same time, by setting an optical base and a laser interferometer measurement component, the precise air film thickness is obtained, and the precise relationship between the air film thickness and the static bearing capacity can be obtained. The relationship between the inclination of the gas bearing and the static bearing capacity or the air film thickness, that is, the inclination characteristic of the gas bearing, can be obtained, thereby accurately evaluating some static characteristics of the gas bearing.

[0006] In one embodiment, the laser interferometry measurement assembly includes a corner cube prism and a laser sensor cooperating with the corner cube prism for measurement. The corner cube prism is disposed on the floating supporting plate, and the laser sensor is disposed on the optical base via a position adaptive adjustment mechanism.

[0007] In one embodiment, the position adaptive adjustment mechanism includes an adaptive coupling adjustment device, which includes a coupling base arranged on the optical base, a vertical bracket arranged on the coupling base, a first transverse bracket arranged on the free end of the vertical bracket, and a second transverse bracket arranged on the free end of the first transverse bracket. The vertical bracket is used to rotate horizontally relative to the coupling base, the first transverse bracket is used to rotate and swing left and right relative to the vertical bracket, the second transverse bracket is used to rotate and swing back and forth relative to the first transverse bracket, and the laser sensor is installed on the free end of the second transverse bracket.

[0008] In one embodiment, the position adaptive adjustment mechanism also includes a laser bracket, the coupling base is arranged on the optical base through the laser bracket, a fixing block for fixing the laser bracket is arranged on the optical base, a first horizontal adjustment structure is arranged between the fixing block and the laser bracket, and the first horizontal adjustment structure is used to adjust the horizontal position of the laser bracket.

[0009] In one embodiment, the first horizontal adjustment structure includes a clamping groove arranged on the fixed block, and the fixed blocks are provided with two blocks, and the two fixed blocks are arranged along the front-to-back direction of the optical base, and an L-shaped or inverted T-shaped clamping groove is provided between the two fixed blocks, and the bottom of the laser bracket is L-shaped or inverted T-shaped, and the bottom of the laser bracket is located in the clamping groove.

[0010] In one embodiment, a base plate is provided at the bottom of the laser bracket, the fixing block includes a clamping seat and a locking seat connected to the clamping seat, the clamping seat is pressed onto the upper side of the base plate, the locking seat is provided on the optical base, and a supporting foot is provided at one end of the bottom of the locking seat protruding downward away from the clamping seat.

[0011] In one embodiment, a first guide groove is provided on the fixing block along the front-rear direction of the optical base, a first adjusting screw is passed through the first guide groove, and the first adjusting screw is screwed on the optical base.

[0012] In one embodiment, the corner cube prism includes a mirror body mounting seat arranged on the floating supporting plate and a prism body arranged on the mirror body mounting seat, and a second guide groove is arranged on the mirror body mounting seat along the front-to-back direction of the optical base, and a second adjustment screw is passed through the second guide groove, and the second adjustment screw is screwed on the floating supporting plate.

[0013] In one embodiment, the high-precision gas bearing static characteristics test bench also includes an angle adjustment mechanism. A second mounting plate is also provided on the optical base. The angle adjustment mechanism is provided with at least two groups, and at least two groups of the angle adjustment mechanisms are distributed on both sides of the test bench. The angle adjustment mechanism includes an adjustment motor provided on the second mounting plate, a precision lead screw provided on the adjustment motor, and an adjustment slider provided on the precision lead screw. The adjustment slider slides along the guide of the precision lead screw to press down the floating bearing plate or move away from the floating bearing plate.

[0014] The present invention also provides a testing method using the above-mentioned high-precision gas bearing static characteristic test bench, comprising the following steps: S1, controlling the detection cylinder to work and driving the floating bearing plate to press against the gas bearing; S2, obtaining a pressure sensor value by measuring with the pressure sensor, and determining a buoyancy value of the gas bearing; S3, measuring and obtaining the gas film thickness value of the gas bearing through the laser interferometer measurement component and determining the inclination of the lower surface of the floating bearing plate; S4, performing static simulation on the floating bearing plate to obtain deformation data; S5. Compensating the average thickness value by deformation data to obtain an accurate thickness value; S6. Determine the static bearing capacity of the gas bearing by the buoyancy value, analyze the relationship between the static bearing capacity of the gas bearing and the thickness of the gas film, analyze the relationship between the inclination of the gas bearing and the static bearing capacity or the thickness of the gas film, and determine the static characteristics of the gas bearing.

[0015] A high-precision gas bearing static characteristics test bench provided by the present invention has at least the following beneficial effects: the present invention drives the floating bearing plate to press against the gas bearing workpiece on the detection bench through a detection cylinder arranged on a suspension bracket, obtains the buoyancy value of the gas bearing through a pressure sensor, and utilizes the frictionless characteristic of the air float ball joint to achieve full adaptability, thereby ensuring that the air film thickness between the upper surface of the gas bearing and the lower surface of the floating bearing plate are the same. At the same time, by setting an optical base and a laser interferometer measurement component, the precise air film thickness is obtained, and the precise relationship between the air film thickness and the static bearing capacity can be obtained. The relationship between the inclination of the gas bearing and the static bearing capacity or the air film thickness, that is, the inclination characteristic of the gas bearing, can be obtained, thereby accurately evaluating some static characteristics of the gas bearing.

[0016] The testing method of the high-precision gas bearing static characteristics test bench provided by the present invention obtains the pressure sensor value through measurement by the pressure sensor, judges the static bearing capacity of the gas bearing, obtains the gas film thickness value of the gas bearing and judges the inclination of the lower surface of the floating bearing plate through measurement by the laser interferometer measurement component, and then compensates the average thickness value through deformation data to obtain the precise thickness value, analyzes the relationship between the static bearing capacity of the gas bearing and the gas film thickness, analyzes the relationship between the inclination of the gas bearing and the static bearing capacity or gas film thickness, and judges the static characteristics of the gas bearing.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 It is a three-dimensional structural diagram of the high-precision gas bearing static characteristic test bench of the present invention; Figure 2 yes Figure 1 A partial enlarged view of middle A; Figure 3 This is a three-dimensional structural diagram of the high-precision gas bearing static characteristics test bench of the present invention with part of the structure hidden; Figure 4 yes Figure 3 A partial enlarged view of B in the middle; Figure 5 It is a three-dimensional structural diagram of a gas bearing; Figure 6 It is a schematic diagram of the first situation when the high-precision gas bearing static characteristic test bench of the present invention is tested; Figure 7 It is a schematic diagram of the second situation when the high-precision gas bearing static characteristic test bench of the present invention is tested; Figure 8 It is a schematic diagram of the third situation when the high-precision gas bearing static characteristic test bench of the present invention is tested; Fig. 9 It is a schematic diagram of a fourth situation when the high-precision gas bearing static characteristic test bench of the present invention is tested; Fig.10 It is a schematic diagram of the fifth situation when the high-precision gas bearing static characteristic test bench of the present invention is tested; Fig.11 It is a schematic diagram of the sixth situation when the high-precision gas bearing static characteristic test bench of the present invention is tested; Fig.12 It is a schematic diagram of the seventh situation when the high-precision gas bearing static characteristic test bench of the present invention is tested; Fig.13 It is a schematic diagram of the eighth situation when the high-precision gas bearing static characteristic test bench of the present invention is tested.

[0019] In the attached drawings: 100-optical base; 200-testing table; 300-first support plate; 4-first mounting plate; 5-air-floating ball joint; 6-pressure sensor; 7-floating bearing plate; 8-corner cone prism; 9-laser sensor; 10-fixed block; 11-clamping groove; 12-first guide groove; 13-first adjusting screw; 14-clamping seat; 15-locking seat; 16-support foot; 17-mirror body mounting seat; 18-prism body; 19-second guide groove; 20-second mounting plate; 21-guide shaft; 22-linear bearing; 23-second support plate; 24-balancing cylinder; 25-laser bracket; 26-gas bearing; 27-adjustment motor; 28-precision screw; 29-adjustment slider; 30-coupling base; 31-vertical bracket; 32-first horizontal bracket; 33-second horizontal bracket; 34-air film. DETAILED DESCRIPTION

[0020] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0021] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0022] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0023] Combine the following Figures 1 to 13 Embodiments of the present invention are described.

[0024] like Figure 1-5 As shown, this embodiment relates to a high-precision gas bearing static characteristic test bench, including an optical base 100, a test bench 200, a suspension bracket, a test cylinder, an air-floating ball joint 5, a pressure sensor 6, a floating bearing plate 7 and a laser interferometer measurement component.

[0025] Specifically, the detection table 200 is arranged on the optical base 100 and is used to place the gas bearing 26 workpiece; the suspension bracket is arranged on the optical base 100; the detection cylinder is arranged on the suspension bracket, and the detection cylinder is located directly above the detection table 200; the air float joint 5, the air float joint 5 is arranged at the driving end of the detection cylinder; the pressure sensor 6, the pressure sensor 6 is arranged at the bottom of the air float joint 5; the floating bearing plate 7, the floating bearing plate 7 is arranged at the bottom of the pressure sensor 6, and the floating bearing plate 7 is used to be pressed on the detection table 200; the laser interferometer measurement component is arranged between the lower surface of the floating bearing plate 7 and the upper surface of the optical base 100, and the laser interferometer measurement component is provided with at least two groups, and at least two groups of laser interferometer measurement components are distributed on both sides of the detection table 200. In this embodiment, the laser interferometer measurement component is provided with four groups, and the four groups of laser interferometer measurement components are not on the same horizontal line at the same time, and are distributed at the four corners of the optical base 100, and are used to measure the displacement and inclination of the lower surface of the floating bearing plate 7.

[0026] On the basis of the above structure, during testing, the gas bearing 26 is placed on the test bench 200, and a positioning column for positioning the gas bearing 26 is provided on the test bench 200. During operation, the driving end of the detection cylinder drives the air float ball joint 5, the pressure sensor 6 and the floating bearing plate 7 to be pressed downward in the direction of the gas bearing 26, and the floating bearing plate 7 is pressed down to the top of the gas bearing 26. In this way, the thrust generated downward by the detection cylinder is balanced with the buoyancy of the gas bearing 26, and the pressure sensor 6 measures the buoyancy of the gas bearing 26, that is, the static bearing capacity of the gas bearing 26.

[0027] Among them, considering the parallelism error between the upper and lower surfaces of the floating bearing plate 7, there are certain problems in using a mechanical ball joint to achieve parallelism adaptation. The mechanical ball joint itself has friction, etc., which will result in the inability to start the mechanical ball joint movement when the parallelism of the floating bearing plate 7 is below a certain value or the buoyancy difference in the corresponding area of ​​the gas bearing 26 is below a certain value. That is, the mechanical ball joint cannot sense the slight difference in the buoyancy of the corresponding area of ​​the measured gas bearing 26 or the slight difference in the thickness of the air film 34, so that the adaptive parallelism cannot be fully achieved, and the adaptive parallelism can only be achieved in some cases; in addition, the mechanical ball joint is easy to increase the different forces at various parts of the floating bearing plate 7, resulting in The required thickness of the air film 34 between the upper surface of the gas bearing 26 and the lower surface of the floating bearing plate 7 is different, which reduces the measurement accuracy of the thickness of the air film 34. Therefore, the test bench adopts the air floating ball joint 5 to achieve the complete adaptive parallelism between the lower surface of the floating bearing plate 7 and the upper surface of the gas bearing 26. The air floating ball joint 5 is frictionless, thereby reducing the interference with the pressure distribution of the air film 34 of the gas bearing 26, thereby improving the measurement accuracy of the thickness of the air film 34, and then improving the accuracy of the relationship between the thickness of the air film 34 and the static bearing capacity, so that the relationship between the static bearing capacity of the gas bearing 26 and the thickness of the air film 34 can be obtained more accurately, that is, more accurate static characteristics of the gas bearing 26 can be obtained; Among them, referring to the schematic diagram of the front and rear areas and the left and right areas of the detection platform 200, the present invention measures the displacement of each part of the floating bearing plate 7 through four laser interferometer measurement components, thereby calculating the left and right inclination and the front and back inclination of the floating bearing plate 7, and then obtaining the thickness difference of the air film 34 in the left and right front and back areas of the gas bearing 26, and then obtaining the pressure distribution difference in the left and right areas and the pressure distribution difference in the front and back areas of the gas bearing 26, thereby obtaining the relationship between the left and right front and back inclination of the gas bearing 26 and the static bearing capacity or the thickness of the air film 34, that is, the inclination characteristics of the gas bearing 26, and then the gas bearing 26 can be improved to achieve a lower left and right front and back inclination, thereby improving the accuracy of the gas bearing 26.

[0028] Among them, taking into account that the floating bearing plate 7 is simultaneously subjected to the downward thrust of the detection cylinder and the upward buoyancy of the gas bearing 26, resulting in deformation of the floating bearing plate 7 itself, it can be seen from the static simulation analysis of the floating bearing plate 7 that the deformation of the upper surface of the floating bearing plate 7 is lower than the deformation of the lower surface, and the deformation of the lower surface of the floating bearing plate 7 is closer to the change in the thickness of the air film 34, and the closer the measurement point of the laser interferometer measurement component is to the edge of the air film 34 between the upper surface of the gas bearing 26 and the lower surface of the floating bearing plate 7, the more accurate the measured thickness of the air film 34. For this reason, this scheme places the laser interferometer measurement component as close to the edge of the air film 34 area as possible in the horizontal plane, thereby improving the measurement accuracy of the thickness of the air film 34.

[0029] like Figure 6As shown, in an ideal situation where there is no parallelism error between the upper and lower surfaces of the test platform 200 , the gas bearing 26 , the buoyant bearing plate 7 , etc., the force F2 measured by the pressure sensor 6 is equal to the buoyancy F1 of the gas bearing 26 .

[0030] like Figure 7 As shown, in the actual situation where there is a parallelism error between the upper and lower surfaces of the detection platform 200, the gas bearing 26, the floating bearing plate 7, etc., when the pressure sensor 6 is arranged between the adaptive parallel structure and the floating bearing plate 7 and moves with the floating bearing plate 7, the force F2 measured by the pressure sensor 6 is equal to the buoyancy F1 of the gas bearing 26.

[0031] like Figure 8 As shown, in the actual situation where there is a parallelism error between the upper and lower surfaces of the test platform 200, the gas bearing 26, the floating bearing plate 7, etc., when the adaptive parallel structure is set between the pressure sensor 6 and the floating bearing plate 7 and the pressure sensor 6 cannot move with the floating bearing plate 7, the force F3 measured by the pressure sensor 6 is not equal to the buoyancy F1 of the gas bearing 26, thereby generating a buoyancy force measurement error.

[0032] like Fig. 9 As shown, under ideal conditions when the gas bearing 26 is completely in the middle of the test bench 200, the combination of the adaptive parallel structure such as the air-floating ball joint 5, the pressure sensor 6, and the floating bearing plate 7 will not be subjected to torque, and the force F2 measured by the pressure sensor 6 is equal to the buoyancy F1 of the gas bearing 26.

[0033] like Fig.10 As shown, when the gas bearing 26 is not completely in the middle of the test platform 200, the combination of the adaptive parallel structure part such as the air-floating ball joint 5, the pressure sensor 6, and the floating bearing plate 7 will be subjected to the torque M1 generated by the buoyancy F1 of the gas bearing 26.

[0034] like Fig.11 As shown, when the combination of the air-floating ball joint 5 and other adaptive parallel structures, the pressure sensor 6, and the floating bearing plate 7 is subjected to the moment M1 generated by the buoyancy F1 of the gas bearing 26, the combination of the air-floating ball joint 5 and other adaptive parallel structures, the pressure sensor 6, and the floating bearing plate 7 will be tilted, which may cause the floating bearing plate 7 to collide with the gas bearing 26 and cause damage. When a mechanical limit is set to avoid collision, the force F2 measured by the pressure sensor 6 may not be equal to the buoyancy F1 of the gas bearing 26, resulting in an error.

[0035] like Fig.12 As shown, in an ideal situation where there is no parallelism error between the upper and lower surfaces of the test platform 200 , the gas bearing 26 , the buoyant bearing plate 7 , etc., the force F2 measured by the pressure sensor 6 is equal to the buoyancy F1 of the gas bearing 26 .

[0036] like Fig.13 As shown, in the actual situation where there is a parallelism error between the upper and lower surfaces of the test platform 200, the gas bearing 26, and the floating bearing plate 7, when an adaptive parallel mechanism with a friction torque) Mf is used, the adaptive parallel mechanism can only be started when (F11-F12)*d>Mf, so that the lower surface of the floating bearing plate 7 is parallel to the upper surface of the gas bearing 26 to be measured, so that the force F2 measured by the pressure sensor 6 is equal to the buoyancy F1 of the gas bearing 26; when (F11-F12)*d≤Mf, the adaptive parallel mechanism cannot be started, and the lower surface of the floating bearing plate 7 cannot be parallel to the upper surface of the gas bearing 26 to be measured. At this time, the air film 34 between the lower surface of the floating bearing plate 7 and the upper surface of the gas bearing 26 to be measured is not a regular rectangle, and the lower surface of the air film 34 is inclined, so the thickness of the air film 34 cannot be accurately measured, that is, there is an error in the thickness measurement of the air film 34. When the thickness of the air film 34 is different, the buoyancy on both sides of the gas bearing 26 is different, that is, F11 is not equal to F12.

[0037] The present invention adopts a frictionless air-floating ball joint 5, Mf=0, so as long as F11 is not equal to F12, even if there is a very small difference between F11 and F12, the adaptive parallel mechanism can be started to achieve adaptive parallelism with high sensitivity, and the buoyancy on the gas bearing 26 and the thickness of the air film 34 can be measured with high accuracy.

[0038] The test principle of the present invention is described as follows: the actual measurement of the laser interferometer measurement component plus static simulation deformation compensation is used to obtain the precise thickness of the air film 34; the frictionless air floating ball joint 5 is used to achieve fully adaptive and precise measurement of the static bearing capacity; and the inclination characteristics of the floating bearing plate 7 are measured by the laser interferometer measurement component. After obtaining the precise static bearing capacity and the precise thickness of the air film 34, the precise relationship between the thickness of the air film 34 and the static bearing capacity can be obtained, and the precise relationship between the static stiffness of the gas bearing 26 and the thickness of the air film 34 can be obtained, and the relationship between the inclination of the gas bearing 26 and the static bearing capacity or the thickness of the air film 34 can be obtained, that is, the inclination characteristics of the gas bearing 26 can be obtained, so that some static characteristics of the gas bearing 26 can be accurately evaluated.

[0039] It can be seen that the present invention drives the floating bearing plate 7 to press against the gas bearing 26 workpiece on the detection platform 200 through the detection cylinder arranged on the suspension bracket, obtains the buoyancy value of the gas bearing 26 through the pressure sensor 6, and uses the frictionless characteristic of the air-floating ball joint 5 to achieve full self-adaptation, thereby ensuring that the ball joint itself will not interfere with the characteristics of the gas bearing 26. At the same time, by setting the optical base 100 and the laser interferometer measurement component, the precise thickness of the air film 34 is obtained, and the precise relationship between the thickness of the air film 34 and the static bearing capacity can be obtained, and the relationship between the left and right front and back inclination of the gas bearing 26 and the thickness or bearing capacity of the air film 34, that is, the inclination characteristic of the gas bearing 26, can be obtained, so that some static characteristics of the gas bearing 26 can be accurately evaluated.

[0040] The laser interferometer measurement assembly includes a corner cube 8 and a laser sensor 9. The laser sensor 9 and the corner cube 8 are measured and matched with each other. The corner cube 8 is arranged on the floating bearing plate 7. In this embodiment, the corner cube 8 is arranged on the lower side of the floating bearing plate 7. The laser sensor 9 is arranged on the optical base 100 through a position adaptive adjustment mechanism. In the above structure technology, when the floating bearing plate 7 is detected, if the floating bearing plate 7 is tilted left and right, tilted front and back, etc., the corner cube 8 arranged on the floating bearing plate 7 will also be tilted left and right, tilted front and back, etc., which will cause a measurement error between the laser sensor 9 and the corner cube 8. In this way, the position adaptive adjustment mechanism is provided to automatically adjust the position of the laser sensor 9 according to the position of the corner cube 8 under the adjustment of the position adaptive adjustment mechanism, so that the laser sensor 9 and the corner cube 8 can achieve accurate measurement and coordination. It should be noted that under the adjustment of the position adaptive adjustment mechanism, the position of the laser sensor 9 can be adjusted in real time according to the position of the corner cube 8, or the position of the laser sensor 9 can be adjusted after the corner cube 8 has a deviation.

[0041] Among them, the position adaptive adjustment mechanism includes an adaptive coupling adjustment device, which includes a coupling base 30, a vertical bracket 31, a first transverse bracket 32 ​​and a second transverse bracket 33. The coupling base 30 is arranged on the optical base 100, the vertical bracket 31 is arranged on the coupling base 30, the first transverse bracket 32 ​​is arranged on the free end of the vertical bracket 31, and the second transverse bracket 33 is arranged on the free end of the first transverse bracket 32. The vertical bracket 31 is used to rotate horizontally relative to the coupling base 30, the first transverse bracket 32 ​​is used to rotate and swing left and right relative to the vertical bracket 31, and the second transverse bracket 33 is used to rotate and swing back and forth relative to the first transverse bracket 32. A laser sensor 9 is installed on the free end of the second transverse bracket 33. When in use, firstly, the vertical bracket 31 can be rotated horizontally relative to the coupling base 30 to drive the first transverse bracket 32, the second transverse bracket 33 and the laser sensor 9 to rotate horizontally, so as to realize the horizontal rotation movement of the laser sensor 9; secondly, the first transverse bracket 32 ​​can be rotated and swung left and right relative to the vertical bracket 31 to drive the second transverse bracket 33 and the laser sensor 9 to rotate and swung left and right to realize the left and right rotation and swing movement of the laser sensor 9; thirdly, the second transverse bracket 33 can be rotated and swung forward and backward relative to the first transverse bracket 32 ​​to drive the laser sensor 9 to rotate and swung forward and backward to realize the front and back rotation and swing movement of the laser sensor 9. It should be noted that the vertical bracket 31, the first transverse bracket 32 ​​and the second transverse bracket 33 can move individually, move together or two of them can move together, and their movement mode is not limited. It can be seen that under the adjustment action of the adaptive coupling adjustment device, the horizontal rotation movement, left and right rotation and swing movement, and front and back rotation and swing movement of the laser sensor 9 can be realized individually, partially or together to meet the position adjustment requirements of the laser sensor 9.

[0042] Among them, a first axial motor is arranged between the coupling base 30 and the vertical bracket 31, and under the driving action of the first axial motor, the vertical bracket 31 is driven to rotate horizontally relative to the coupling base 30. A second axial motor is arranged between the vertical bracket 31 and the first transverse bracket 32, and under the driving action of the second axial motor, the first transverse bracket 32 ​​is driven to rotate and swing left and right relative to the vertical bracket 31. A third axial motor is arranged between the first transverse bracket 32 ​​and the second transverse bracket 33, and under the driving action of the third axial motor, the second transverse bracket 33 is driven to rotate and swing back and forth relative to the first transverse bracket 32.

[0043] Among them, the position adaptive adjustment mechanism also includes a laser bracket 25, and the coupling base 30 is arranged on the optical base 100 through the laser bracket 25. A fixing block 10 for fixing the laser bracket 25 is arranged on the optical base 100, and a first horizontal adjustment structure is arranged between the fixing block 10 and the laser bracket 25. The first horizontal adjustment structure is used to adjust the horizontal position of the laser bracket 25. In this way, by adjusting the horizontal position of the laser bracket 25 using the first horizontal adjustment structure, the position of the coupling base 30 on the laser bracket 25 can be adjusted, and then the position of the entire adaptive coupling adjustment device can be adjusted. Therefore, this scheme can realize two-stage position adjustment through the adaptive coupling adjustment device and the laser bracket 25, thereby improving the position adjustment capability of the equipment.

[0044] Among them, the first horizontal adjustment structure includes a clamping groove 11 set on the fixed block 10, and the laser bracket 25 is clamped and fixed by the clamping groove 11, that is, it is fixed by clamping. There are two fixed blocks 10, and the two fixed blocks 10 are arranged along the front and rear directions of the optical base 100. By ensuring that the pressing force on both sides of the bottom of the laser bracket 25 is the same, the tilt or deformation caused by the unbalanced force of the laser bracket 25 is avoided, thereby affecting the position and posture of the laser sensor 9, thereby ensuring the measurement accuracy of the laser interferometer measurement component. Further, an L-shaped or inverted T-shaped clamping groove 11 is set between the two fixed blocks 10, and the bottom of the laser bracket 25 is L-shaped or inverted T-shaped, and the bottom of the laser bracket 25 is located in the clamping groove 11. Through the L-shaped or inverted T-shaped assembly structure, the laser bracket 25 is prevented from detaching from the top, so that the laser bracket 25 can only move left and right and forward and backward in the horizontal plane along the clamping groove 11 after the fixed block 10 is loosened. In this embodiment, the clamping groove 11 is inverted T-shaped.

[0045] Among them, a base plate is provided at the bottom of the laser bracket 25, and the fixing block 10 includes a clamping seat 14 and a locking seat 15 connected to the clamping seat 14. The clamping seat 14 is pressed on the upper side of the base plate, and the locking seat 15 is arranged on the optical base 100. The bottom of the locking seat 15 is away from the clamping seat 14 and one end thereof protrudes downward and is provided with a supporting foot 16. With the support of the supporting foot 16, there is a spacing between the bottom of one side of the clamping seat 14 and the optical base 100. Through this spacing, the clamping seat 14 can be appropriately tilted to press the base plate, thereby achieving a better pressing effect.

[0046] The fixing block 10 is provided with a first guide groove 12 along the front-to-back direction of the optical base 100, and a first adjusting screw 13 is inserted into the first guide groove 12, and the first adjusting screw 13 is screwed on the optical base 100. Thus, when the first adjusting screw 13 is loosened, the fixing block 10 can be adjusted and moved along the front-to-back direction of the optical base 100 under the guidance of the first guide groove 12, so that the position of the fixing block 10 can be adjusted, and the position of the laser bracket 25 can be adjusted by adjusting the position of the fixing block 10.

[0047] It can be seen that the laser bracket 25 can be adjusted and moved left and right under the guidance of the clamping groove 11. At the same time, the fixed block 10 can be adjusted and moved along the front and rear direction of the optical base 100 under the guidance of the first guide groove 12, that is, the front and rear adjustment movement of the laser bracket 25 is indirectly realized, thereby meeting the needs of the front and rear and left and right adjustment movement of the laser bracket 25. Therefore, this solution can achieve three-level position adjustment through the adaptive coupling adjustment device, the laser bracket 25 and the fixed block 10, thereby improving the position adjustment capability of the equipment.

[0048] The corner cube prism 8 includes a mirror body mounting seat 17 and a prism body 18. The mirror body mounting seat 17 is arranged on the floating bearing plate 7. Specifically, the mirror body mounting seat 17 is arranged on the lower side of the floating bearing plate 7, and the prism body 18 is arranged on the mirror body mounting seat 17. A second horizontal adjustment structure for adjusting the horizontal position of the corner cube prism 8 is arranged between the mirror body mounting seat 17 and the floating bearing plate 7. The position of the corner cube prism 8 is adjusted by the second horizontal adjustment structure. Further, the second horizontal adjustment structure includes a second guide groove 19 arranged on the mirror body mounting seat 17 and a second adjustment screw connected in the second guide groove 19. The second guide groove 19 extends along the front-to-back direction of the optical base 100. The second adjustment screw is screwed on the floating bearing plate 7. In this way, when the second adjustment screw is loosened, the mirror body mounting seat 17 can be adjusted and moved along the front-to-back direction of the optical base 100 under the guidance of the second guide groove 19 to achieve the position adjustment of the prism body 18, thereby meeting the position adjustment requirements of the prism body 18.

[0049] Among them, not shown in the figure, the laser sensor 9 and the prism body 18 are both provided with posture sensors, and the posture sensors are gyroscope space posture sensors. The posture sensors are used to measure the pitch angle, roll angle, and yaw angle of the laser sensor 9 and the prism body 18 respectively. According to the measurement results, the laser sensor 9 and the prism body 18 are adjusted and aligned to ensure the measurement accuracy of the laser interferometer measurement component, thereby improving the measurement accuracy of the static characteristics of the gas bearing 26.

[0050] Among them, the suspension bracket includes a first support plate 300 arranged on the optical base 100 and a first mounting plate 4 arranged on the top of the first support plate 300, and the first mounting plate 4 is located above the test bench 200. The high-precision gas bearing 26 static characteristic test bench also includes an angle adjustment mechanism, and a bearing bracket assembly is also arranged on the optical base 100. The bearing bracket assembly includes a second mounting plate 20, a guide shaft 21, a linear bearing 22 and a second support plate 23. The second support plate 23 is arranged on the optical base 100, and the second mounting plate 20 is arranged on the top of the second support plate 23. The second mounting plate 20 is located below the first mounting plate 4, the guide shaft 21 is arranged above the second mounting plate 20, and the linear bearing 22 is arranged below the second mounting plate 20. The detection cylinder is arranged above the first mounting plate 4, and the driving end of the detection cylinder passes through the guide shaft 21, the second mounting plate 20 and the linear bearing 22 in sequence and is connected to the air floating ball joint 5, so that the driving end of the detection cylinder is affected by the guide shaft 21 and the linear bearing 22 when moving, thereby ensuring the test accuracy of the equipment. Among them, the detection cylinder is a balancing cylinder 24, thereby further ensuring the testing accuracy of the equipment.

[0051] Among them, at least two groups of angle adjustment mechanisms are provided, and at least two groups of angle adjustment mechanisms are distributed on both sides of the detection platform 200. In this embodiment, four groups of angle adjustment mechanisms are provided, and the angle adjustment mechanisms include an adjustment motor 27 provided on the second mounting plate 20, a precision lead screw 28 provided on the adjustment motor 27, and an adjustment slider 29 provided on the precision lead screw 28. The adjustment slider 29 slides along the guide of the precision lead screw 28 to press down the floating bearing plate 7 or to move away from the floating bearing plate 7. On the basis of the above structure, the inclination of the floating bearing plate 7 is detected and determined by the laser interferometer measurement component. If the inclination occurs, the position of the floating bearing plate 7 can be adjusted by the angle adjustment mechanism. Specifically, the position adjustment is achieved by sliding the adjustment slider 29 along the guide of the precision lead screw 28 to press down the floating bearing plate 7 or to move away from the floating bearing plate 7. For example, when the floating bearing plate 7 is tilted so that one side is too high, the floating bearing plate 7 can be adjusted by pressing down the adjustment slider 29 to adjust the position. When the position does not need to be adjusted, the adjustment slider 29 is moved away from the floating bearing plate 7 to avoid interference in measurement movement.

[0052] Among them, when there are four groups of laser interferometer measurement components, two groups of laser interferometer measurement components are arranged in front of the detection platform 200, and two groups of laser interferometer measurement components are arranged behind the detection platform 200. Considering that the bearing capacity of the gas bearing 26 is different as the thickness of the air film 34 changes, resulting in different deformations of the floating bearing plate 7 and the detection platform 200, the deformations of the floating bearing plate 7 and the detection platform 200 are obtained by performing static simulation on the floating bearing plate 7 and the detection platform 200 under different bearing capacities, and the deformation obtained by simulation is used to compensate for the thickness of the air film 34 measured by the four laser interferometer measurement components, so as to obtain a sufficiently accurate thickness of the air film 34.

[0053] The distance is measured by four laser interferometer measurement components and then the average value is obtained to obtain the value of the thickness of the air film 34 between the upper surface of the gas bearing 26 and the lower surface of the floating bearing plate 7. The distances of the four points can obtain the three degrees of freedom of the floating bearing plate 7, namely, the Z-direction movement, the rotation around the X-direction, and the rotation around the Y-direction. The Z-direction movement can obtain the change in the thickness of the air film 34, and the rotation around the X-direction and the rotation around the Y-direction can determine the distribution symmetry of the bearing capacity of the gas bearing 26, and more accurately evaluate the static performance of the gas bearing 26.

[0054] The present invention also provides a testing method using the above-mentioned high-precision gas bearing static characteristic test bench, comprising the following steps: S1, control the detection cylinder to work, drive the floating bearing plate 7 to press against the gas bearing 26; S2, obtaining the value of the pressure sensor 6 by measuring the pressure sensor 6, and determining the buoyancy value of the gas bearing 26; S3, measuring and obtaining the thickness value of the gas film 34 of the gas bearing 26 by means of a laser interferometer measurement component; S4, performing static simulation on the floating bearing plate 7 to obtain deformation data; S5. Compensating the average thickness value by deformation data to obtain an accurate thickness value; S6. Determine the static bearing capacity of the gas bearing 26 by the buoyancy value, analyze the relationship between the static bearing capacity of the gas bearing 26 and the thickness of the air film 34, and the relationship between the front and rear tilt of the gas bearing 26 and the thickness and bearing capacity of the air film 34, and determine the static characteristics of the gas bearing 26.

[0055] It can be seen that the present invention obtains the value of the pressure sensor 6 through the pressure sensor 6 to determine the static bearing capacity of the gas bearing 26, obtains the thickness value of the air film 34 of the gas bearing 26 through the laser interferometer measurement component and determines the inclination of the lower surface of the floating bearing plate 7, and then compensates the average thickness value through the deformation data to obtain the precise thickness value, analyzes the relationship between the static bearing capacity of the gas bearing 26 and the thickness of the air film 34, analyzes the relationship between the inclination of the gas bearing 26 and the static bearing capacity or the thickness of the air film 34, and determines the static characteristics of the gas bearing 26.

[0056] Among them, as different embodiments, the corner cube prism 8 is magnetically fixed to the lower side of the floating supporting plate 7, and the laser bracket 25 is magnetically fixed to the optical base 100, that is, the corner cube prism 8 and the laser bracket 25 are both fixed by magnetic attraction. Compared with the use of a position adaptive adjustment mechanism or a screw locking structure, the adjustment is more convenient and quick, which is conducive to improving the efficiency of position adjustment.

[0057] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of the present invention.

Claims

1. A high-precision gas bearing static characteristics test bench, characterized in that: High-precision gas bearing static characteristics test bench includes: Optical base; A detection platform, arranged on the optical base, for placing a gas bearing workpiece; A suspension bracket, arranged on the optical base; A detection cylinder, wherein the detection cylinder is arranged on the suspension bracket and is located directly above the detection platform; An air-floating ball joint, the air-floating ball joint being arranged at the driving end of the detection cylinder; A pressure sensor, wherein the pressure sensor is arranged at the bottom of the air-floating ball joint; A floating bearing plate, the floating bearing plate is arranged at the bottom of the pressure sensor, and the floating bearing plate is used for pressing on the detection platform; A laser interferometer measurement component is arranged between the lower surface of the floating supporting plate and the upper surface of the optical base. There are at least two groups of laser interferometer measurement components, and at least two groups of laser interferometer measurement components are distributed on both sides of the detection platform to measure the displacement and inclination of the lower surface of the floating supporting plate.

2. The high-precision gas bearing static characteristics test bench according to claim 1 is characterized in that: The laser interferometry measurement assembly includes a corner cube prism and a laser sensor that cooperates with the corner cube prism for measurement. The corner cube prism is arranged on the floating supporting plate, and the laser sensor is arranged on the optical base through a position adaptive adjustment mechanism.

3. The high-precision gas bearing static characteristics test bench according to claim 2 is characterized in that: The position adaptive adjustment mechanism includes an adaptive coupling adjustment device, which includes a coupling base arranged on the optical base, a vertical bracket arranged on the coupling base, a first transverse bracket arranged on the free end of the vertical bracket, and a second transverse bracket arranged on the free end of the first transverse bracket. The vertical bracket is used to rotate horizontally relative to the coupling base, the first transverse bracket is used to rotate and swing left and right relative to the vertical bracket, the second transverse bracket is used to rotate and swing back and forth relative to the first transverse bracket, and the laser sensor is installed on the free end of the second transverse bracket.

4. The high-precision gas bearing static characteristics test bench according to claim 3 is characterized in that: The position adaptive adjustment mechanism also includes a laser bracket, the coupling base is arranged on the optical base through the laser bracket, a fixing block for fixing the laser bracket is arranged on the optical base, a first horizontal adjustment structure is arranged between the fixing block and the laser bracket, and the first horizontal adjustment structure is used to adjust the horizontal position of the laser bracket.

5. The high-precision gas bearing static characteristics test bench according to claim 4 is characterized in that: The first horizontal adjustment structure includes a clamping groove arranged on the fixed block, and there are two fixed blocks. The two fixed blocks are arranged along the front and rear directions of the optical base, and an L-shaped or inverted T-shaped clamping groove is arranged between the two fixed blocks. The bottom of the laser bracket is L-shaped or inverted T-shaped, and the bottom of the laser bracket is located in the clamping groove.

6. The high-precision gas bearing static characteristics test bench according to claim 4, characterized in that: A base plate is provided at the bottom of the laser bracket, and the fixing block includes a clamping seat and a locking seat connected to the clamping seat, the clamping seat is pressed on the upper side of the base plate, the locking seat is provided on the optical base, and a supporting foot is provided at one end of the bottom of the locking seat which protrudes downward away from the clamping seat.

7. The high-precision gas bearing static characteristics test bench according to claim 4, characterized in that: The fixing block is provided with a first guide groove along the front-rear direction of the optical base, a first adjusting screw is passed through the first guide groove, and the first adjusting screw is screwed on the optical base.

8. The high-precision gas bearing static characteristics test bench according to claim 2, characterized in that: The corner cube prism includes a mirror body mounting seat arranged on the floating supporting plate and a prism body arranged on the mirror body mounting seat, a second guide groove is arranged on the mirror body mounting seat along the front-to-back direction of the optical base, a second adjustment screw is passed through the second guide groove, and the second adjustment screw is screwed on the floating supporting plate.

9. The high-precision gas bearing static characteristics test bench according to claim 1, characterized in that: The high-precision gas bearing static characteristics test bench also includes an angle adjustment mechanism. A second mounting plate is also provided on the optical base. The angle adjustment mechanism is provided with at least two groups, and at least two groups of the angle adjustment mechanisms are distributed on both sides of the test bench. The angle adjustment mechanism includes an adjustment motor provided on the second mounting plate, a precision lead screw provided on the adjustment motor, and an adjustment slider provided on the precision lead screw. The adjustment slider slides along the guide of the precision lead screw to press down the floating bearing plate or move away from the floating bearing plate.

10. A test method for a high-precision gas bearing static characteristic test bench according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, controlling the detection cylinder to work and driving the floating bearing plate to press against the gas bearing; S2, obtaining a pressure sensor value by measuring with the pressure sensor, and determining a buoyancy value of the gas bearing; S3, measuring and obtaining the gas film thickness value of the gas bearing through the laser interferometer measurement component and determining the inclination of the lower surface of the floating bearing plate; S4, performing static simulation on the floating bearing plate to obtain deformation data; S5. Compensating the average thickness value by deformation data to obtain an accurate thickness value; S6. Determine the static bearing capacity of the gas bearing by the buoyancy value, analyze the relationship between the static bearing capacity of the gas bearing and the thickness of the gas film, analyze the relationship between the inclination of the gas bearing and the static bearing capacity or the thickness of the gas film, and determine the static characteristics of the gas bearing.

Images