A high-precision gas bearing static characteristic test bench and a test method thereof

Abstract

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

Description

TECHNICAL FIELD

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

[0002] The gas bearing has the advantages of high speed, high precision and no friction, and is widely used in industry, and is mainly used in the technical field of super-speed and super-precision movement. In order to ensure the high precision and stability of the movement, it is necessary to test the static characteristics of the gas bearing. Considering that the gas film thickness of the gas bearing is generally in microns, the measurement accuracy is very high. At present, the existing bearing measuring device has large error and low accuracy, and it is difficult to accurately obtain the static characteristics of the gas bearing, so it is necessary to further improve the detection precision. SUMMARY

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

[0004] The present application provides a high-precision gas bearing static characteristic test bench, which comprises: an optical base; a detection bench arranged on the optical base and used for placing a gas bearing workpiece; a suspension support arranged on the optical base; a detection cylinder arranged on the suspension support and located directly above the detection bench; a gas floating ball hinge arranged at the driving end of the detection cylinder; a pressure sensor arranged at the bottom of the gas floating ball hinge; an upper floating bearing plate arranged at the bottom of the pressure sensor and used for pressing on the detection bench; and a laser interferometric measurement assembly arranged between the lower surface of the upper floating bearing plate and the upper surface of the optical base, wherein the laser interferometric measurement assembly is provided with at least two groups, and the at least two groups of laser interferometric measurement assemblies are distributed on both sides of the detection bench and used for measuring the displacement and inclination of the lower surface of the upper floating bearing plate.

[0005] Therefore, the detection cylinder arranged on the suspension support drives the upper floating bearing plate to press the gas bearing workpiece on the detection bench, the pressure sensor obtains the upper floating force value of the gas bearing, the gas floating ball hinge is completely self-adaptive due to its frictionless characteristic, the gas film thickness between the upper surface of the gas bearing and the lower surface of the upper floating bearing plate is ensured to be the same, the optical base and the laser interferometric measurement assembly are arranged to obtain the accurate gas film thickness, the relationship between the accurate gas film thickness and the static bearing capacity is obtained, and the relationship between the inclination of the gas bearing and the static bearing capacity or the gas film thickness, i.e. the inclination characteristic of the gas bearing, is obtained, so that the partial static characteristics of the gas bearing can be accurately evaluated.

[0006] In one embodiment, the laser interferometer assembly comprises a corner cube and a laser sensor in measurement cooperation with the corner cube, the corner cube is arranged on the upper floating carrier plate, and the laser sensor is arranged on the optical base through a position self-adapting adjustment mechanism.

[0007] In one embodiment, the position self-adapting adjustment mechanism comprises an adaptive coupling adjustment device, the adaptive coupling adjustment device comprises a coupling base arranged on the optical base, a vertical support arranged on the coupling base, a first horizontal support arranged on a free end of the vertical support, and a second horizontal support arranged on a free end of the first horizontal support, the vertical support is used for horizontal rotation relative to the coupling base, the first horizontal support is used for left-right rotation swing relative to the vertical support, and the second horizontal support is used for front-back rotation swing relative to the first horizontal support, and a free end of the second horizontal support is provided with the laser sensor.

[0008] In one embodiment, the position self-adapting adjustment mechanism further comprises a laser support, the coupling base is arranged on the optical base through the laser support, the optical base is provided with a fixing block for fixing the laser support, a first horizontal adjustment structure is arranged between the fixing block and the laser support, and the first horizontal adjustment structure is used for adjusting the horizontal position of the laser support.

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

[0010] In one embodiment, the bottom of the laser support is provided with a bottom plate, the fixing block comprises a clamping seat and a locking seat connected with the clamping seat, the clamping seat is pressed on an upper side of the bottom plate, the locking seat is arranged on the optical base, and a bottom of the locking seat is provided with a support leg which is arranged in a downward protruding manner away from one end of the clamping seat.

[0011] In one embodiment, a first guide groove is arranged on the fixing block in a front-back direction of the optical base, a first adjusting screw is arranged in the first guide groove, and the first adjusting screw is screwed on the optical base.

[0012] In one embodiment, the corner prism comprises a mirror mounting seat arranged on the upper floating carrier plate, and a prism body arranged on the mirror mounting seat, the mirror mounting seat is provided with a second guide groove in the front-rear direction of the optical base, a second adjusting screw is arranged in the second guide groove, and the second adjusting screw is screwed on the upper floating carrier plate.

[0013] In one embodiment, the high-precision gas bearing static characteristic test table further comprises an angle adjusting mechanism, the optical base is further provided with a second mounting plate, the angle adjusting mechanism is provided with at least two groups, the at least two groups of angle adjusting mechanisms are distributed on both sides of the detection table, and the angle adjusting mechanism comprises an adjusting motor arranged on the second mounting plate, a precision screw rod arranged on the adjusting motor, and an adjusting sliding block arranged on the precision screw rod, the adjusting sliding block slides along the guide of the precision screw rod, and the upper floating carrier plate is pressed or away from the upper floating carrier plate.

[0014] The application further provides a test method using the high-precision gas bearing static characteristic test table, comprising the following steps:

[0015] S1, controlling the detection cylinder to work and driving the upper floating carrier plate to press the gas bearing;

[0016] S2, measuring and obtaining the pressure sensor value through the pressure sensor, and judging the upper floating force value of the gas bearing;

[0017] S3, measuring and obtaining the gas film thickness value of the gas bearing and judging the inclination of the lower surface of the upper floating carrier plate through the laser interference measurement assembly;

[0018] S4, obtaining deformation data by simulating the statics of the upper floating carrier plate;

[0019] S5, compensating the average thickness value through the deformation data to obtain the accurate thickness value;

[0020] S6, judging the static bearing capacity of the gas bearing through the upper floating force value, analyzing the relationship between the static bearing capacity of the gas bearing and the gas film thickness, analyzing the relationship between the inclination of the gas bearing and the static bearing capacity or the gas film thickness, and judging the static characteristics of the gas bearing.

[0021] The high-precision gas bearing static characteristic test table provided by the application has at least the following beneficial effects: the detection gas cylinder arranged on the suspension support drives the floating bearing plate to press the gas bearing workpiece on the detection table, the floating force value of the gas bearing is obtained by the pressure sensor, the completely self-adapting is realized by using the frictionless characteristics of the gas floating ball hinge, the gas film thickness between the upper surface of the gas bearing and the lower surface of the floating bearing plate is ensured to be the same, the accurate gas film thickness is obtained by arranging the optical base and the laser interference measurement assembly, the relationship between the accurate gas 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 gas film thickness, i.e., the inclination characteristics of the gas bearing, can be obtained, and thus the partial static characteristics of the gas bearing can be accurately evaluated.

[0022] The test method of the high-precision gas bearing static characteristic test table provided by the application comprises the following steps: measuring and obtaining the pressure sensor value by the pressure sensor, judging the static bearing capacity of the gas bearing, measuring and obtaining the gas film thickness value of the gas bearing and judging the inclination of the lower surface of the floating bearing plate by the laser interference measurement assembly, obtaining the accurate thickness value by compensating the average thickness value through the deformation data, analyzing the relationship between the static bearing capacity of the gas bearing and the gas film thickness, analyzing the relationship between the inclination of the gas bearing and the static bearing capacity or the gas film thickness, and judging the static characteristics of the gas bearing.

[0023] Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following and / or can be learned by practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0024] The above and / or additional aspects and advantages of the application will become apparent and be readily understood by considering the following detailed description, from which the above-mentioned aspects and advantages will become apparent, and in which embodiments of the application are shown and described, merely by way of illustration.

[0025] Figure 1 is a perspective view of the high-precision gas bearing static characteristic test table of the application;

[0026] Figure 2 is Figure 1 is a partial enlarged view of A in the figure;

[0027] Figure 3 is a perspective view of the high-precision gas bearing static characteristic test table of the application after the hidden part structure is removed;

[0028] Figure 4 is Figure 3 is a partial enlarged view of B in the figure;

[0029] Figure 5 is a perspective view of the gas bearing;

[0030] Figure 6A first case schematic view for testing of the high-precision gas bearing static characteristic test table of the application;

[0031] Figure 7 A second case schematic view for testing of the high-precision gas bearing static characteristic test table of the application;

[0032] Figure 8 A third case schematic view for testing of the high-precision gas bearing static characteristic test table of the application;

[0033] Figure 9 A fourth case schematic view for testing of the high-precision gas bearing static characteristic test table of the application;

[0034] Figure 10 A fifth case schematic view for testing of the high-precision gas bearing static characteristic test table of the application;

[0035] Figure 11 A sixth case schematic view for testing of the high-precision gas bearing static characteristic test table of the application;

[0036] Figure 12 A seventh case schematic view for testing of the high-precision gas bearing static characteristic test table of the application;

[0037] Figure 13 An eighth case schematic view for testing of the high-precision gas bearing static characteristic test table of the application.

[0038] In the drawings: 100 - optical base; 200 - detection table; 300 - first support plate; 4 - first mounting plate; 5 - air floating ball hinge; 6 - pressure sensor; 7 - upper floating bearing plate; 8 - corner 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 - balance air cylinder; 25 - laser support; 26 - gas bearing; 27 - adjusting motor; 28 - precision lead screw; 29 - adjusting sliding block; 30 - shaft coupling base; 31 - vertical support; 32 - first transverse support; 33 - second transverse support; 34 - gas film. DETAILED DESCRIPTION

[0039] Embodiments of the present application are described in detail below with reference to examples illustrated in the accompanying drawings, in which the same or similar components are denoted by the same or similar reference numerals throughout. The embodiments described below by reference to the accompanying drawings are exemplary and are intended to explain the present application, and should not be construed as limiting the present application.

[0040] In the description of the present application, it should be understood that the orientation description, such as the orientation or position relationship indicated by the upper, lower, front, rear, left, right and the like, is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0041] In the description of the present application, unless otherwise explicitly defined, the words such as setting, mounting, connecting and the like should be broadly understood, and the person skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0042] The following will be described in combination with Figures 1 to 13 The embodiments of the present application are described.

[0043] As Figures 1-5 shown, the present embodiment relates to a high-precision gas bearing static characteristic test bench, which comprises an optical base 100, a detection table 200, a suspension bracket, a detection cylinder, a gas floating ball hinge 5, a pressure sensor 6, an upper floating bearing plate 7 and a laser interference measurement assembly.

[0044] Specifically, the detection table 200 is arranged on the optical base 100 and used for placing a gas bearing 26 workpiece; the suspension bracket is arranged on the optical base 100; the detection cylinder is arranged on the suspension bracket and located directly above the detection table 200; the gas floating ball hinge 5 is arranged at the driving end of the detection cylinder; the pressure sensor 6 is arranged at the bottom of the gas floating ball hinge 5; the upper floating bearing plate 7 is arranged at the bottom of the pressure sensor 6 and used for being pressed on the detection table 200; the laser interference measurement assembly is arranged between the lower surface of the upper floating bearing plate 7 and the upper surface of the optical base 100, and the laser interference measurement assembly is provided with at least two groups, and the at least two groups of laser interference measurement assemblies are distributed on both sides of the detection table 200. In the present embodiment, the laser interference measurement assembly is provided with four groups, and the four groups of laser interference measurement assemblies are not on the same horizontal straight line at the same time and are distributed on the four corners of the optical base 100, and are used for measuring the displacement and inclination of the lower surface of the upper floating bearing plate 7.

[0045] On the basis of the above structure, during testing, the gas bearing 26 is placed on the detection table 200, the detection table 200 is provided with a positioning column for positioning the gas bearing 26, and during operation, the detection cylinder drives the gas floating ball hinge 5, the pressure sensor 6 and the upper floating bearing plate 7 to press downward to the direction of the gas bearing 26, and the upper floating bearing plate 7 is pressed to the upper side of the gas bearing 26, so that the downward thrust of the detection cylinder and the upper floating force of the gas bearing 26 reach balance, and thus the upper floating force of the gas bearing 26 is measured by the pressure sensor 6, that is, the static bearing capacity of the gas bearing 26.

[0046] Wherein, considering that the upper and lower surfaces of the upper floating bearing plate 7 have parallelism error, there are certain problems in realizing parallelism self-adaptation by using mechanical ball hinge, and the mechanical ball hinge itself has friction and the like, which can cause that when the parallelism of the upper floating bearing plate 7 is below a certain value or the upper floating force difference of the corresponding area of the gas bearing 26 is below a certain value, the mechanical ball hinge cannot be started to move, that is, the mechanical ball hinge cannot sense the small difference of the upper floating force of the corresponding area of the measured gas bearing 26 or the small difference of the gas film 34 thickness, so that the self-adaptive parallelism cannot be completely realized, but only the self-adaptive parallelism in some cases can be realized; in addition, the mechanical ball hinge is easy to increase the stress difference of each part of the upper floating bearing plate 7, causing the gas film 34 thickness between the upper surface of the gas bearing 26 and the lower surface of the upper floating bearing plate 7 to be different, thereby reducing the measurement accuracy of the gas film 34 thickness, so that the test table adopts the gas floating ball hinge 5 to realize the complete self-adaptive parallelism between the lower surface of the upper floating bearing plate 7 and the upper surface of the gas bearing 26, the gas floating ball hinge 5 has no friction, thereby reducing the interference to the gas film 34 pressure distribution of the gas bearing 26, improving the measurement accuracy of the gas film 34 thickness, and then improving the accuracy of the relationship between the gas film 34 thickness and the static bearing capacity, so that the relationship between the static bearing capacity of the gas bearing 26 and the gas film 34 thickness can be more accurately obtained, that is, the static characteristics of the gas bearing 26 can be more accurately obtained;

[0047] Wherein, referring to the front and rear area and the left and right area of the detection table 200, the displacement amount of each part of the upper floating bearing plate 7 is measured by the four laser interference measurement assemblies, so that the left and right inclination and the front and rear inclination of the upper floating bearing plate 7 are calculated, and then the gas film 34 thickness difference of the left and right area and the front and rear area of the gas bearing 26 is obtained, that is, the pressure distribution difference of the left and right area and the front and rear area of the gas bearing 26 is obtained, so that the relationship between the left and right inclination and the front and rear inclination of the gas bearing 26 and the static bearing capacity or the gas film 34 thickness is obtained, that is, the inclination characteristics of the gas bearing 26 is obtained, and then the gas bearing 26 can be improved to realize lower left and right inclination and front and rear inclination, and the accuracy of the gas bearing 26 is improved.

[0048] Wherein, considering that the floating bearing plate 7 is subjected to the downward force of the detection cylinder and the upward force of the gas bearing 26 at the same time, resulting in the deformation of the floating bearing plate 7 itself, through the static simulation analysis of the floating bearing plate 7, it is known that the deformation of the upper surface of the floating bearing plate 7 is lower than that of the lower surface, the deformation of the lower surface of the floating bearing plate 7 is closer to the change of the thickness of the gas film 34, and the closer the measurement point of the laser interference measurement assembly to the edge of the gas 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 gas film 34 is, therefore, the laser interference measurement assembly is arranged as close as possible to the edge of the gas film 34 region in the horizontal plane, so as to improve the measurement accuracy of the thickness of the gas film 34.

[0049] As shown in Figure 6 , when the ideal situation that the upper and lower surfaces of the detection table 200, the gas bearing 26, the floating bearing plate 7 and the like do not have parallelism error, the force F2 measured by the pressure sensor 6 is equal to the upward force F1 of the gas bearing 26.

[0050] As shown in Figure 7 , in the actual situation that the upper and lower surfaces of the detection table 200, the gas bearing 26, the floating bearing plate 7 and the like have parallelism error, when the pressure sensor 6 is arranged between the adaptive parallel structure and the floating bearing plate 7 and follows the floating bearing plate 7, the force F2 measured by the pressure sensor 6 is equal to the upward force F1 of the gas bearing 26.

[0051] As shown in Figure 8 , in the actual situation that the upper and lower surfaces of the detection table 200, the gas bearing 26, the floating bearing plate 7 and the like have parallelism error, when the adaptive parallel structure is arranged between the pressure sensor 6 and the floating bearing plate 7, and the pressure sensor 6 cannot follow the floating bearing plate 7, the force F3 measured by the pressure sensor 6 is not equal to the upward force F1 of the gas bearing 26, thereby generating an upward force measurement error.

[0052] As shown in Figure 9 , when the gas bearing 26 is completely in the middle of the detection table 200 in the ideal situation, the combination of part of the adaptive parallel structure such as the gas floating ball hinge 5, the pressure sensor 6 and the floating bearing plate 7 will not be subjected to a moment, and the force F2 measured by the pressure sensor 6 is equal to the upward force F1 of the gas bearing 26.

[0053] As shown in Figure 10 , when the gas bearing 26 is not completely in the middle of the detection table 200, the combination of part of the adaptive parallel structure such as the gas floating ball hinge 5, the pressure sensor 6 and the floating bearing plate 7 will be subjected to a moment M1 generated by the upward force F1 of the gas bearing 26.

[0054] As shown in Figure 11As shown, when the combination of the adaptive parallel structure part, the pressure sensor 6, and the upper floating bearing plate 7 of the gas floating ball hinge 5 is subjected to the moment M1 generated by the upper floating force F1 of the gas bearing 26, the combination of the adaptive parallel structure part, the pressure sensor 6, and the upper floating bearing plate 7 will be tilted, which may cause the upper floating bearing plate 7 to collide with the gas bearing 26, resulting in damage. When mechanical limiting or other measures are taken to avoid collision, the force F2 measured by the pressure sensor 6 may not be equal to the upper floating force F1 of the gas bearing 26, and there is an error.

[0055] As shown in FIG. 1, when the detection table 200, the gas bearing 26, and the upper and lower surfaces of the upper floating bearing plate 7 do not have parallelism error, the force F2 measured by the pressure sensor 6 is equal to the upper floating force F1 of the gas bearing 26. Figure 12

[0056] As shown in FIG. 1, when the detection table 200, the gas bearing 26, and the upper and lower surfaces of the upper floating bearing plate 7 do not have parallelism error, the force F2 measured by the pressure sensor 6 is equal to the upper floating force F1 of the gas bearing 26. Figure 13 As shown in FIG. 1, when the detection table 200, the gas bearing 26, and the upper and lower surfaces of the upper floating bearing plate 7 do not have parallelism error, the force F2 measured by the pressure sensor 6 is equal to the upper floating force F1 of the gas bearing 26.

[0057] The present application adopts a frictionless gas floating ball hinge 5, and Mf=0, so as long as F11 is not equal to F12, even if F11 and F12 have very small differences, the adaptive parallel mechanism can be started to realize adaptive parallel, the sensitivity is high, and the measurement accuracy of the upper floating force of the gas bearing 26 and the thickness of the gas film 34 is high.

[0058] ​The test principle of the present application is explained as follows: the actual measurement of the laser interference measurement assembly is added to the static simulation deformation compensation to obtain the accurate gas film 34 thickness; the completely self-adaptive and accurate measurement of the static bearing capacity is realized through the frictionless air floating ball hinge 5; the inclination characteristics of the floating bearing plate 7 are measured through the laser interference measurement assembly. After obtaining the accurate static bearing capacity and the accurate gas film 34 thickness, the relationship between the accurate gas film 34 thickness and the static bearing capacity can be obtained, and the relationship between the static stiffness of the gas bearing 26 and the gas film 34 thickness can be obtained, and the relationship between the inclination of the gas bearing 26 and the static bearing capacity or the gas film 34 thickness, i.e. the inclination characteristics of the gas bearing 26, can be obtained, so that the partial static characteristics of the gas bearing 26 can be accurately evaluated.

[0059] As can be seen, the present application drives the floating bearing plate 7 to press the workpiece of the gas bearing 26 on the detection table 200 through the detection cylinder arranged on the suspension support, the floating force value of the gas bearing 26 is obtained through the pressure sensor 6, the completely self-adaptive is realized by using the frictionless characteristics of the air floating ball hinge 5, the ball hinge itself does not interfere with the characteristics of the gas bearing 26, the optical base 100 and the laser interference measurement assembly are arranged to obtain the accurate gas film 34 thickness, the relationship between the accurate gas film 34 thickness and the static bearing capacity can be obtained, and the relationship between the left and right and front and back inclination of the gas bearing 26 and the gas film 34 thickness or the bearing capacity, i.e. the inclination characteristics of the gas bearing 26, can be obtained, so that the partial static characteristics of the gas bearing 26 can be accurately evaluated.

[0060] The laser interference measurement assembly includes the corner cube prism 8 and the laser sensor 9, the laser sensor 9 and the corner cube prism 8 are mutually measured and matched, the corner cube prism 8 is arranged on the floating bearing plate 7, in the embodiment, the corner cube prism 8 is arranged on the lower side of the floating bearing plate 7, and the laser sensor 9 is arranged on the optical base 100 through the position self-adaptive adjusting mechanism. In the above structure, when the floating bearing plate 7 appears left and right inclination, front and back inclination and the like during detection, the corner cube prism 8 arranged on the floating bearing plate 7 also appears left and right inclination, front and back inclination and the like, and then the measurement error between the laser sensor 9 and the corner cube prism 8 appears, so that the position self-adaptive adjusting mechanism is arranged to automatically adjust the position of the laser sensor 9 according to the position of the corner cube prism 8 under the adjustment of the position self-adaptive adjusting mechanism, so that the laser sensor 9 and the corner cube prism 8 realize accurate measurement matching. It should be noted that the position of the laser sensor 9 can be adjusted in real time according to the position of the corner cube prism 8 under the adjustment of the position self-adaptive adjusting mechanism, or the position of the laser sensor 9 is adjusted after the corner cube prism 8 deviates.

[0061] The position self-adapting adjusting mechanism comprises an adaptive coupling adjusting device, the adaptive coupling adjusting device comprises a coupling base 30, a vertical support 31, a first horizontal support 32 and a second horizontal support 33, the coupling base 30 is arranged on the optical base 100, the vertical support 31 is arranged on the coupling base 30, the first horizontal support 32 is arranged on the free end of the vertical support 31, the second horizontal support 33 is arranged on the free end of the first horizontal support 32, the vertical support 31 is used for horizontal rotation relative to the coupling base 30, the first horizontal support 32 is used for left-right rotary swing relative to the vertical support 31, the second horizontal support 33 is used for front-back rotary swing relative to the first horizontal support 32, and the free end of the second horizontal support 33 is provided with the laser sensor 9. In use, firstly, the vertical support 31 can be used for horizontal rotation relative to the coupling base 30 to drive the first horizontal support 32, the second horizontal support 33 and the laser sensor 9 to horizontally rotate, so that the horizontal rotary movement of the laser sensor 9 is realized; secondly, the first horizontal support 32 can be used for left-right rotary swing relative to the vertical support 31 to drive the second horizontal support 33 and the laser sensor 9 to left-right rotary swing, so that the left-right rotary swing movement of the laser sensor 9 is realized; and thirdly, the second horizontal support 33 can be used for front-back rotary swing relative to the first horizontal support 32 to drive the laser sensor 9 to front-back rotary swing, so that the front-back rotary swing movement of the laser sensor 9 is realized. It should be noted that the vertical support 31, the first horizontal support 32 and the second horizontal support 33 can be moved individually, jointly or two of them can be moved jointly, and the movement mode is not limited. As can be seen, under the adjustment of the adaptive coupling adjusting device, the horizontal rotary movement, the left-right rotary swing movement and the front-back rotary swing movement of the laser sensor 9 can be realized individually, partially or jointly to meet the position adjustment requirement of the laser sensor 9.

[0062] The first axial motor is arranged between the coupling base 30 and the vertical support 31, and drives the vertical support 31 to horizontally rotate relative to the coupling base 30 under the driving action of the first axial motor. The second axial motor is arranged between the vertical support 31 and the first horizontal support 32, and drives the first horizontal support 32 to left-right rotary swing relative to the vertical support 31 under the driving action of the second axial motor. The third axial motor is arranged between the first horizontal support 32 and the second horizontal support 33, and drives the second horizontal support 33 to front-back rotary swing relative to the first horizontal support 32 under the driving action of the third axial motor.

[0063] The position self-adapting mechanism further comprises a laser support 25, the coupling base 30 is arranged on the optical base 100 through the laser support 25, the optical base 100 is provided with a fixing block 10 for fixing the laser support 25, a first horizontal adjusting structure is arranged between the fixing block 10 and the laser support 25, and the first horizontal adjusting structure is used for adjusting the horizontal position of the laser support 25. Thus, the horizontal position of the laser support 25 is adjusted by using the first horizontal adjusting structure, the position of the coupling base 30 on the laser support 25 is adjusted, and then the position of the entire self-adapting coupling adjusting device is adjusted, so that the two-stage position adjustment is realized by the self-adapting coupling adjusting device and the laser support 25, and the position adjusting capacity of the equipment is improved.

[0064] The first horizontal adjusting structure comprises a clamping groove 11 arranged on the fixing block 10, and the laser support 25 is clamped and fixed by the clamping groove 11, that is, the clamping manner is adopted for fixing. The fixing block 10 is provided with two blocks, the two fixing blocks 10 are arranged along the front-rear direction of the optical base 100, the same compression force is ensured on both sides of the bottom of the laser support 25, so that the inclination or deformation of the laser support 25 caused by the unbalanced force is avoided, and then the pose of the laser sensor 9 is affected, so that the measurement accuracy of the laser interference measurement assembly is ensured. Further, the clamping groove 11 in an L shape or an inverted T shape is arranged between the two fixing blocks 10, the bottom of the laser support 25 is in an L shape or an inverted T shape, and the bottom of the laser support 25 is located in the clamping groove 11. Through the L-shaped or inverted T-shaped assembly structure, the laser support 25 is prevented from being separated from above, so that the laser support 25 can only move left and right, forward and backward in the horizontal plane along the clamping groove 11 after the fixing block 10 is loosened. In the embodiment, the clamping groove 11 is in an inverted T shape.

[0065] The bottom of the laser support 25 is provided with a bottom plate, the fixing block 10 comprises a clamping seat 14 and a locking seat 15 connected with the clamping seat 14, the clamping seat 14 is pressed on the upper side of the bottom plate, the locking seat 15 is arranged on the optical base 100, the bottom of the locking seat 15 is provided with a support leg 16 which is arranged in a downward protruding manner away from one end of the clamping seat 14, under the support of the support leg 16, the bottom of one side of the clamping seat 14 has a spacing with the optical base 100, through the spacing, the clamping seat 14 can be moderately inclined to press the bottom plate, so that a better pressing effect is realized.

[0066] The first guide slot 12 is arranged on the fixed block 10 along the front-rear direction of the optical base 100, the first adjusting screw 13 is arranged in the first guide slot 12, and the first adjusting screw 13 is screwed on the optical base 100. In this way, when the first adjusting screw 13 is loosened, the fixed block 10 can be adjusted and moved along the front-rear direction of the optical base 100 under the guidance of the first guide slot 12, the position adjustment of the fixed block 10 is realized, and then the position of the laser support 25 can be adjusted by adjusting the position of the fixed block 10.

[0067] Therefore, the laser support 25 can be adjusted and moved left and right under the guidance of the clamping groove 11, and the fixed block 10 can be adjusted and moved along the front-rear direction of the optical base 100 under the guidance of the first guide slot 12, that is, the front-rear adjustment and movement of the laser support 25 is indirectly realized, so that the front-rear-left-right adjustment and movement of the laser support 25 is met, and then the three-level position adjustment of the self-adaptive coupling adjustment device, the laser support 25 and the fixed block 10 is realized, and the position adjustment capability of the equipment is improved.

[0068] The corner cube prism 8 comprises a mirror body mounting seat 17 and a prism body 18. The mirror body mounting seat 17 is arranged on the upper floating bearing plate 7, specifically, the mirror body mounting seat 17 is arranged on the lower side of the upper floating bearing plate 7, the prism body 18 is arranged on the mirror body mounting seat 17, and the 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 upper floating bearing plate 7. The position of the corner cube prism 8 is adjusted through the second horizontal adjustment structure. Further, the second horizontal adjustment structure comprises a second guide slot 19 arranged on the mirror body mounting seat 17 and a second adjusting screw arranged in the second guide slot 19. The second guide slot 19 extends along the front-rear direction of the optical base 100, and the second adjusting screw is screwed on the upper floating bearing plate 7. In this way, when the second adjusting screw is loosened, the mirror body mounting seat 17 can be adjusted and moved along the front-rear direction of the optical base 100 under the guidance of the second guide slot 19, the position adjustment of the prism body 18 is realized, and then the position adjustment requirement of the prism body 18 is met.

[0069] The laser sensor 9 and the prism body 18 are both provided with a pose sensor, which is not shown in the figure. The pose sensor is a gyroscope space pose sensor, and is used for measuring 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 in real time, so as to ensure the measurement accuracy of the laser interference measurement assembly, and improve the measurement accuracy of the static characteristics of the gas bearing 26.

[0070] The suspension support comprises 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 detection table 200. The high-precision gas bearing 26 static characteristic test table further comprises an angle adjusting mechanism, and the optical base 100 is further provided with a bearing support assembly, the bearing support assembly comprises 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, 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, 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 is connected with the gas floating ball hinge 5 in sequence through the guide shaft 21, the second mounting plate 20 and the linear bearing 22, 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 precision of the equipment. The detection cylinder is a balance cylinder 24, thereby further ensuring the test precision of the equipment.

[0071] The angle adjusting mechanism comprises at least two groups, and the at least two groups of angle adjusting mechanisms are distributed on both sides of the detection table 200. In the embodiment, the angle adjusting mechanism comprises four groups, and the angle adjusting mechanism comprises an adjusting motor 27 arranged on the second mounting plate 20, a precision lead screw 28 arranged on the adjusting motor 27 and an adjusting sliding block 29 arranged on the precision lead screw 28. The adjusting sliding block 29 slides along the guide of the precision lead screw 28 to press down or move away from the upper floating bearing plate 7. On the basis of the above structure, the inclination of the upper floating bearing plate 7 is detected and judged by the laser interference measurement assembly. When the inclination occurs, the position of the upper floating bearing plate 7 is adjusted by the angle adjusting mechanism. Specifically, the position is adjusted by sliding the adjusting sliding block 29 along the guide of the precision lead screw 28 to press down or move away from the upper floating bearing plate 7. For example, when the inclination of the upper floating bearing plate 7 causes one side to be too high, the adjusting sliding block 29 is used to press down the upper floating bearing plate 7 to adjust the position. When the position does not need to be adjusted, the adjusting sliding block 29 is moved away from the upper floating bearing plate 7 to avoid measurement motion interference.

[0072] When the laser interference measurement assembly is provided with four groups, two groups of laser interference measurement assemblies are arranged in front of the detection table 200, and the other two groups of laser interference measurement assemblies are arranged behind the detection table 200. Considering that the load capacity of the gas bearing 26 is different with the change of the gas film 34 thickness, thereby causing the deformation of the floating bearing plate 7 and the detection table 200 to be different, the deformation of the floating bearing plate 7 and the detection table 200 is obtained by static simulation of the floating bearing plate 7 and the detection table 200 under different load capacities, and the deformation obtained by simulation is used to compensate the gas film 34 thickness measured by the four laser interference measurement assemblies, so that the gas film 34 thickness is obtained with sufficient accuracy.

[0073] The thickness of the gas film 34 between the upper surface of the gas bearing 26 and the lower surface of the floating bearing plate 7 is obtained by averaging the distances measured by the four laser interference measurement assemblies. The distances of the four points can obtain three degrees of freedom of the floating bearing plate 7, i.e. Z-direction movement, rotation around X-direction and rotation around Y-direction. The Z-direction movement can obtain the change of the gas film 34 thickness, and the rotation around X-direction and the rotation around Y-direction can judge the symmetry of the load capacity distribution of the gas bearing 26, and more accurately evaluate the static performance of the gas bearing 26.

[0074] The application also provides a test method using the high-precision gas bearing static characteristic test table, comprising the following steps:

[0075] S1, control the detection cylinder to work and drive the floating bearing plate 7 to press against the gas bearing 26;

[0076] S2, measure the pressure sensor 6 value through the pressure sensor 6, and judge the floating force value of the gas bearing 26;

[0077] S3, measure the gas film 34 thickness value of the gas bearing 26 through the laser interference measurement assembly;

[0078] S4, obtain the deformation data by static simulation of the floating bearing plate 7;

[0079] S5, compensate the average thickness value by the deformation data to obtain the accurate thickness value;

[0080] S6, judge the static load capacity of the gas bearing 26 by the floating force value, analyze the relationship between the static load capacity of the gas bearing 26 and the gas film 34 thickness, the relationship between the front and rear and left and right inclination of the gas bearing 26 and the gas film 34 thickness and the load capacity, and judge the static characteristics of the gas bearing 26.

[0081] Therefore, the application measures and obtains the pressure sensor 6 value through the pressure sensor 6, judges the static load capacity of the gas bearing 26, measures and obtains the gas film 34 thickness value of the gas bearing 26 through the laser interference measurement assembly and judges the inclination of the lower surface of the floating bearing plate 7, then compensates the average thickness value through the deformation data to obtain the accurate thickness value, analyzes the relationship between the static load capacity of the gas bearing 26 and the gas film 34 thickness, analyzes the relationship between the inclination of the gas bearing 26 and the static load capacity or the gas film 34 thickness, and judges the static characteristics of the gas bearing 26.

[0082] Among them, as different embodiments, the corner cube prism 8 is magnetically attracted and fixed on the lower side of the floating bearing plate 7, and the laser support 25 is magnetically attracted and fixed on the optical base 100, that is, the corner cube prism 8 and the laser support 25 are both fixed in a magnetic attraction mode, which is more convenient and fast in adjustment compared with the position self-adaptive adjustment mechanism or the screw locking structure, and is beneficial to improving the position adjustment efficiency.

[0083] The preferred embodiments of the application are specifically described above, but the application is not limited to the above-mentioned embodiments, and those skilled in the art can make various equivalent modifications or replacements without departing from the spirit of the application. These equivalent modifications or replacements are all included in the scope defined by the claims of the application.

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 is provided 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 float ball joint, the air float ball joint being arranged at the driving end of the detection cylinder; A pressure sensor is provided at the bottom of the air float joint; A floating bearing plate, the floating bearing plate being arranged at the bottom of the pressure sensor and being used for pressing onto the detection platform; a laser interferometry assembly disposed between the lower surface of the floating support plate and the upper surface of the optical base, wherein at least two groups of the laser interferometry assemblies are provided, and the at least two groups of the laser interferometry assemblies are distributed on both sides of the detection platform, for measuring the displacement and tilt of the lower surface of the floating support plate; 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; 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 horizontal bracket arranged on the free end of the vertical bracket, and a second horizontal bracket arranged on the free end of the first horizontal bracket. The vertical bracket is used to rotate horizontally relative to the coupling base, the first horizontal bracket is used to rotate and swing left and right relative to the vertical bracket, and the second horizontal bracket is used to rotate and swing back and forth relative to the first horizontal bracket. The laser sensor is installed on the free end of the second horizontal bracket.

2. The high-precision gas bearing static characteristics test bench according to claim 1, 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, and a fixing block for fixing the laser bracket is provided on the optical base. A first horizontal adjustment structure is provided 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.

3. The high-precision gas bearing static characteristics test bench according to claim 2, 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 provided 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.

4. The high-precision gas bearing static characteristics test bench according to claim 2, characterized in that: A base plate is provided at the bottom of the laser bracket, and the fixed 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, and the locking seat is provided on the optical base. A supporting foot is provided on one end of the bottom of the locking seat protruding downward away from the clamping seat.

5. The high-precision gas bearing static characteristics test bench according to claim 2, characterized in that: 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. The first adjusting screw is screwed onto the optical base.

6. The high-precision gas bearing static characteristics test bench according to claim 1, 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 provided 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 onto the floating supporting plate.

7. 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 in 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 screw provided on the adjustment motor, and an adjustment slider provided on the precision screw. The adjustment slider slides along the guide of the precision screw to press down the floating bearing plate or move away from the floating bearing plate.

8. A testing method for a high-precision gas bearing static characteristics test bench according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1, controlling the detection cylinder to operate and drive the floating bearing plate to press against the gas bearing; S2. Obtaining a pressure sensor value by measuring the pressure sensor, and determining a buoyancy value of the gas bearing; S3, measuring the gas film thickness of the gas bearing by the laser interferometry assembly 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. Compensate the average thickness value by deformation data to obtain the 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.

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