System and method for regulating and controlling rotation precision of hydrostatic bearing

Abstract

The invention discloses a hydrostatic bearing rotation precision regulation and control system and method, and relates to the technical field of bearing rotation precision regulation and control. A to-be-tested module comprises a bearing support and a standard ball; the rotation precision regulation and control module comprises a direct-current power supply, a first actuator assembly and a second actuator assembly, the first actuator assembly comprises a first coil, the second actuator assembly comprises a second coil, and the first coil and the second coil are arranged on the two sides of the hydrostatic bearing respectively and output positive current and negative current respectively; the direct-current power supply supplies current to the first coil and the second coil through two pairs of output ends respectively; and the upper computer is used for regulating and controlling the magnitude of the output current of the two output ends of the direct-current power supply according to the detection data of the displacement sensor. The problem that the rotation precision is restrained by the limit of manufacturing errors of parts of the hydrostatic bearing is solved, and the rotation precision of the hydrostatic bearing is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of bearing rotation precision control, and in particular to a system and method for controlling the rotation precision of a hydrostatic bearing. Background Art

[0002] Hydrostatic bearings are widely used in ultra-precision machining machines and testing equipment due to their low friction, high precision and long life. The performance of hydrostatic bearings greatly affects the quality of machining and testing. Among them, rotational accuracy is the main representation of the kinematic performance of hydrostatic bearings. Poor rotational accuracy will directly affect the feed quality and the authenticity of measurement data. In recent years, the industry has increasingly higher requirements for machining and testing accuracy, and has also placed higher requirements on the rotational accuracy of hydrostatic bearings.

[0003] Research shows that the rotation accuracy of hydrostatic bearings is 1 / 4-1 / 3 of the manufacturing error of hydrostatic bearing parts. Therefore, the methods for improving the rotation accuracy of hydrostatic bearings in the prior art generally involve reducing the manufacturing error of hydrostatic bearing parts. However, the manufacturing error of parts is often limited by the machining accuracy of machine tools, and the improvement of machining accuracy is in turn limited by the rotation accuracy of hydrostatic bearings. This vicious cycle makes it difficult to achieve a breakthrough in the rotation accuracy of hydrostatic bearings. Summary of the invention

[0004] The present invention aims to solve the deficiencies of the prior art and to provide a system and method for controlling the rotation accuracy of a hydrostatic bearing so as to solve the problem of the limit of manufacturing errors of hydrostatic bearing parts suppressing the rotation accuracy and to improve the rotation accuracy of the hydrostatic bearing.

[0005] The present invention is achieved through the following technical solutions:

[0006] A hydrostatic bearing rotation accuracy control system, comprising:

[0007] A module to be tested, the module to be tested comprising a bearing bracket and a standard ball, the bearing bracket is used to fix the stator of the hydrostatic bearing, and the standard ball is coaxially connected to the rotor of the hydrostatic bearing through a rod;

[0008] A rotation accuracy measurement module, the rotation accuracy measurement module includes a displacement sensor and a host computer, the displacement sensor is arranged on one side of the standard ball and is used to detect the displacement of the standard ball;

[0009] A rotation precision control module, the rotation precision control module comprising a DC power supply, a first actuator assembly and a second actuator assembly, the first actuator assembly comprising a first coil, the second actuator assembly comprising a second coil, the first coil and the second coil being arranged on both sides of the static pressure bearing and outputting a positive current and a negative current respectively; the DC power supply supplies current to the first coil and the second coil respectively through two pairs of output terminals;

[0010] The host computer is used to respectively adjust the output current magnitudes of the two output ends of the DC power supply according to the detection data of the displacement sensor.

[0011] Compared with the prior art, the method for improving the rotation accuracy of hydrostatic bearings is generally to reduce the manufacturing errors of hydrostatic bearing parts; however, the manufacturing errors of parts are often limited by the machining accuracy of machine tools, and the improvement of machining accuracy is limited by the rotation accuracy of hydrostatic bearings. This vicious cycle makes it difficult to achieve a breakthrough in the rotation accuracy of hydrostatic bearings. The present invention provides a system and method for controlling the rotation accuracy of hydrostatic bearings. By adopting the present invention, the hydrostatic bearing mover can be pulled back by the traction of electromagnetic force, thereby improving the rotation accuracy of the hydrostatic bearing. In the specific scheme, the control system includes a module to be tested, a rotation accuracy measurement module and a rotation accuracy control module, wherein the module to be tested includes a bearing bracket for fixing the stator of the hydrostatic bearing to ensure that the stator of the hydrostatic bearing is stationary; a standard ball is also extended outward through a rod at the end of the hydrostatic bearing mover, and the standard ball and the mover of the hydrostatic bearing are coaxial, so that the rotation drive of the rotor is driven by the lower driver to drive the internal motor to complete the rotation, and the rotation of the mover of the hydrostatic bearing will drive the standard ball to rotate synchronously and coaxially. The high-precision standard ball is used as the target of the displacement sensor, which can effectively reduce the interference of the roundness error of the target object on the measurement data; so as to facilitate displacement detection through the displacement sensor; the rotation accuracy measurement module includes a displacement sensor and a host computer, and the displacement sensor is fixed on one side of the standard ball to detect the moving trajectory of the center of the standard ball, and transmit the data to the host computer. Through the calculation and judgment of the host computer, the rotation accuracy control module is controlled to adjust the rotation accuracy of the hydrostatic bearing. The rotation accuracy control module includes a DC power supply, a first actuator assembly and a second actuator assembly. The DC power supply is used to supply current to the first MOS tube and the second MOS tube respectively. The MOS tube is controlled by the PWM wave of the signal generator to output current to the coil, and the coil generates electromagnetic force through the iron core electromagnetism. In addition, the current on the first coil and the second coil is controllable. By reducing the current on one coil, a pulling force can be provided to the static pressure bearing mover in the direction of the coil, thereby moving the static pressure bearing mover back and forth from the deviation direction to the original axis of the static pressure bearing, so as to improve the rotation accuracy of the static pressure bearing.

[0012] In order to facilitate the installation of the hydrostatic bearing and save installation space, the bearing bracket includes a top ring plate and a bottom ring plate, the diameter of the top ring plate is smaller than the diameter of the bottom ring plate; the circumferential end of the top ring plate is connected to the circumferential end of the bottom ring plate through a plurality of support rods;

[0013] The static pressure bearing stator and the center hole of the top ring plate are coaxially detachably connected. In this solution, the top ring plate is used to carry the static pressure bearing, and the shoulder of the static pressure bearing and the top ring plate are connected by bolts; in addition, by setting the bearing bracket to a structure with a small top and a large bottom, it is convenient to place the rotation accuracy control module inside the bearing bracket to save installation space.

[0014] In order to isolate vibration, an optical platform is also included, the bearing bracket is detachably connected to the optical platform, and the optical platform is provided with an air spring.

[0015] In order to realize the fixation of the displacement sensor and data transmission, the rotation accuracy measurement module also includes a sensor fixture and a data acquisition box, and the sensor fixture is detachably connected to the stator of the static pressure bearing;

[0016] The sensor fixture is used to clamp the displacement sensor;

[0017] The data acquisition box is used to collect data from the displacement sensor and transmit the data to the host computer.

[0018] In order to raise the installation height of the displacement sensor so that the displacement sensor can face the standard ball, a U-shaped plate is also fixed on the bearing bracket, and the U-shaped plate is inverted on the static pressure bearing stator; a through hole is opened on the upper end surface of the U-shaped plate for the standard ball to pass through; and the sensor fixture is fixed on the upper end surface of the U-shaped plate.

[0019] In order to provide currents of different amplitudes, the rotation accuracy control module further includes a first MOS tube, a second MOS tube and a signal generator; a pair of output ends of the DC power supply are connected to the positive and negative poles of the power supply of the first MOS tube, and are connected to the first coil through the first MOS tube; another pair of output ends of the DC power supply are connected to the positive and negative poles of the power supply of the second MOS tube, and are connected to the second coil through the second MOS tube.

[0020] The rotation accuracy control module further includes a signal generator, and two pairs of output ends of the signal generator are respectively connected to the positive and negative electrodes of the signal control ends of the first MOS tube and the second MOS tube;

[0021] The signal generator is used to receive the control signal of the host computer, and control the opening and closing of the first MOS tube and the second MOS tube respectively. In this scheme, the MOS tube has three terminals, which are divided into a power input terminal connected to a DC power supply, a signal control terminal connected to the signal generator, and an output current terminal connected to a coil. The signal at the signal control terminal determines whether the MOS tube is internally conductive, and further determines whether the output current terminal outputs current; the signal generator can transmit the control signal of the host computer, and provide signals with different parameters as the switch control signals of the first MOS tube and the second MOS tube; and provide currents of different amplitudes through the DC power supply to control the magnitude of the output current of the first MOS tube and the second MOS tube respectively.

[0022] In order to monitor the change of the tension given to the hydrostatic bearing by the two coils, the first actuator assembly further includes a first fixed block, a first force sensor and a first iron core, wherein the first fixed block is fixed on the stator of the hydrostatic bearing, the first fixed block is connected to the first iron core through the first force sensor, and the first iron core is located on a side of the first coil away from the hydrostatic bearing;

[0023] The second actuator assembly also includes a second fixed block, a second force sensor and a second iron core, wherein the second fixed block is fixed on the stator of the hydrostatic bearing, the second fixed block is connected to the second iron core through the second force sensor, and the second iron core is located on the side of the second coil away from the hydrostatic bearing. In this solution, the iron core is placed on the side of the coil away from the hydrostatic bearing, so that a tensile force is applied to the iron core. The iron core is fixed on the fixed block through the force sensor, and the change in the tensile force can be monitored through the force sensor to improve the control accuracy.

[0024] To achieve detachable connection of the force sensor, both sides of the first force sensor and the second force sensor are provided with threads, the two ends of the first force sensor are respectively threadedly connected to the first fixing block and the first iron core, and the two ends of the second force sensor are respectively threadedly connected to the second fixing block and the second iron core.

[0025] As a further solution, the present invention also provides a control method for a hydrostatic bearing rotation accuracy control system, comprising the following steps:

[0026] S1: locating the original axis of the hydrostatic bearing and the center coordinates of the standard ball by means of a displacement sensor;

[0027] S2: driving the rotor of the hydrostatic bearing to rotate through a driver;

[0028] S3: Turn on the DC power supply and supply current to the first MOS tube and the second MOS tube;

[0029] S4: collecting several circles of movement trajectory of the center of the standard ball through a displacement sensor, and transmitting the data to a host computer;

[0030] S5: The host computer calculates the center coordinate value of each circle and takes the average of several center coordinate values; then compares the average with the original axis of the standard ball to obtain the deviation direction and deviation size;

[0031] S6: When the mover of the hydrostatic bearing rotates to the deviation direction and is located in the same plane as the first coil and the second coil, the DC power supply is controlled by the host computer to change the supply current to the first coil or the second coil according to the deviation size; the first MOS tube and the second MOS tube are turned on, and current is output to the first coil and the second coil through the first MOS tube and the second MOS tube, thereby pulling back the hydrostatic bearing mover through electromagnetic force.

[0032] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0033] The present invention provides a system and method for controlling the rotation accuracy of a hydrostatic bearing. By adopting the present invention, the hydrostatic bearing mover can be pulled back by electromagnetic force, thereby improving the rotation accuracy of the hydrostatic bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0035] Figure 1 A schematic diagram of the structure of the hydrostatic bearing rotation accuracy control system provided by the present invention;

[0036] Figure 2 A schematic diagram of the structure of the module to be tested and the rotation accuracy measurement module provided by the present invention;

[0037] Figure 3 A control circuit diagram of the rotation accuracy control module provided by the present invention;

[0038] Figure 4 A schematic diagram of the flow chart of the hydrostatic bearing rotation accuracy control system provided by the present invention.

[0039] Marks and corresponding parts names in the attached drawings:

[0040] 1-optical platform, 2-module to be tested, 21-standard ball, 22-static pressure bearing, 23-bearing bracket, 3-rotation accuracy measurement module, 31-displacement sensor, 32-sensor fixture, 33-data acquisition box, 34-host computer, 4-rotation accuracy control module, 41-signal generator, 42-DC power supply, 43-first MOS tube, 44-first actuator assembly, 441-first fixed block, 442-first force sensor, 443-first iron core, 444-first coil, 45-second MOS tube, 46-second actuator assembly, 461-second fixed block, 462-second force sensor, 463-second iron core, 464-second coil. DETAILED DESCRIPTION

[0041] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0042] Embodiment 1:

[0043] This embodiment 1 provides a hydrostatic bearing rotation accuracy control system, such as Figure 1-Figure 3 As shown, including:

[0044] The module to be tested 2 comprises a bearing bracket 23 and a standard ball 21, wherein the bearing bracket 23 is used to fix the stator of the hydrostatic bearing 22, and the standard ball 21 is coaxially connected with the rotor of the hydrostatic bearing 22 through a rod;

[0045] A rotation accuracy measurement module 3, the rotation accuracy measurement module 3 includes a displacement sensor 31 and a host computer 34, the displacement sensor 31 is arranged on one side of the standard ball 21 and is used to detect the displacement of the standard ball 21;

[0046] The rotation precision control module 4 includes a DC power supply 42, a first actuator assembly 44 and a second actuator assembly 46. The first actuator assembly 44 includes a first coil 444, and the second actuator assembly 46 includes a second coil 464. The first coil 444 and the second coil 464 are respectively arranged on both sides of the static pressure bearing 22, and output positive current and negative current respectively. The DC power supply 42 supplies current to the first coil 444 and the second coil 464 through two pairs of output terminals respectively.

[0047] The host computer 34 is used to adjust the output current of the two output terminals of the DC power supply 42 according to the detection data of the displacement sensor 31.

[0048] Compared with the prior art, the method for improving the rotation accuracy of the hydrostatic bearing 22 is generally to reduce the manufacturing errors of the parts of the hydrostatic bearing 22; however, the manufacturing errors of the parts are often limited by the machining accuracy of the machine tool, and the improvement of the machining accuracy is limited by the rotation accuracy of the hydrostatic bearing 22. This vicious cycle makes it difficult to achieve a breakthrough in the rotation accuracy of the hydrostatic bearing 22. The present invention provides a system and method for controlling the rotation accuracy of the hydrostatic bearing 22. By adopting the present invention, the mover of the hydrostatic bearing 22 can be pulled back by the traction of electromagnetic force, thereby improving the rotation accuracy of the hydrostatic bearing 22. In the specific scheme, the control system includes a module to be tested 2, a rotation accuracy measurement module 3 and a rotation accuracy control module 4, wherein the module to be tested 2 includes a bearing bracket 23 for fixing the stator of the hydrostatic bearing 22 to ensure that the stator of the hydrostatic bearing 22 is stationary; a standard ball 21 is also extended outward through a rod at the end of the mover of the hydrostatic bearing 22, and the standard ball 21 is coaxial with the mover of the hydrostatic bearing 22. In this way, the rotation drive of the rotor is driven by the lower driver to drive the internal motor to complete the rotation, and the rotation of the mover of the hydrostatic bearing 22 will drive the standard ball 21 to rotate synchronously and coaxially. The high-precision standard ball 21 is used as the target of the displacement sensor 31, which can effectively reduce the interference of the roundness error of the target object on the measurement data; so as to facilitate displacement detection through the displacement sensor 31; the rotation accuracy measurement module 3 includes a displacement sensor 31 and a host computer 34. The displacement sensor 31 is fixed on one side of the standard ball 21, so as to detect the moving trajectory of the center of the standard ball 21, and transmit the data to the host computer 34. Through the calculation and judgment of the host computer 34, the rotation accuracy control module 4 is controlled to adjust the rotation accuracy of the static pressure bearing 22. The rotation accuracy control module 4 includes a DC power supply 42, a first actuator component 44 and a second actuator component 46. The DC power supply 42 is used to supply current to the first MOS tube 43 and the second MOS tube 45 respectively. The MOS tube is controlled by the PWM wave of the signal generator to output current to the coil, and the coil generates electromagnetic force through the iron core electromagnetism. In addition, the current on the first coil 444 and the second coil 464 is controllable. By reducing the current on one coil, a pulling force can be provided to the mover of the hydrostatic bearing 22 toward the coil direction, thereby moving the mover of the hydrostatic bearing 22 from the deviated direction back and forth to the original axis of the hydrostatic bearing 22, so as to improve the rotation accuracy of the hydrostatic bearing 22.

[0049] In order to facilitate the installation of the hydrostatic bearing 22 and save installation space, the bearing bracket 23 includes a top ring plate and a bottom ring plate, the diameter of the top ring plate is smaller than the diameter of the bottom ring plate; the circumferential end of the top ring plate is connected to the circumferential end of the bottom ring plate through a plurality of support rods;

[0050] The stator of the static pressure bearing 22 and the center hole of the top ring plate are coaxially detachably connected. In this solution, the top ring plate is used to carry the static pressure bearing 22, and the shoulder of the static pressure bearing 22 and the top ring plate are connected by bolts; in addition, by setting the bearing bracket 23 to a structure with a small top and a large bottom, it is convenient to place the rotation accuracy control module 4 inside the bearing bracket 23 to save installation space.

[0051] In order to isolate vibration, an optical platform 1 is also included. The bearing bracket 23 is detachably connected to the optical platform 1, and the optical platform 1 is provided with an air spring.

[0052] In order to realize the fixation and data transmission of the displacement sensor 31, the rotation accuracy measurement module 3 further includes a sensor fixture 32 and a data acquisition box 33, and the sensor fixture 32 is detachably connected to the stator of the static pressure bearing 22;

[0053] The sensor fixture 32 is used to clamp the displacement sensor 31;

[0054] The data acquisition box 33 is used to collect data from the displacement sensor 31 and transmit the data to the host computer 34 .

[0055] In order to raise the installation height of the displacement sensor 31 so that the displacement sensor 31 can face the standard ball 21, a U-shaped plate is also fixed on the bearing bracket 23, and the U-shaped plate is inverted on the stator of the static pressure bearing 22; a through hole is opened on the upper end surface of the U-shaped plate for the standard ball 21 to pass through; the sensor fixture 32 is fixed on the upper end surface of the U-shaped plate.

[0056] In order to provide currents of different amplitudes, the rotation accuracy control module 4 also includes a first MOS tube 43, a second MOS tube 45 and a signal generator 41. A pair of output ends of the DC power supply 42 are connected to the positive and negative poles of the power supply of the first MOS tube 43, and are connected to the first coil 444 through the first MOS tube 43; another pair of output ends of the DC power supply 42 are connected to the positive and negative poles of the power supply of the second MOS tube 45, and are connected to the second coil 464 through the second MOS tube 45.

[0057] The rotation accuracy control module 4 further includes a signal generator 41, and two pairs of output ends of the signal generator 41 are respectively connected to the positive and negative electrodes of the signal control ends of the first MOS transistor 43 and the second MOS transistor 45;

[0058] The signal generator 41 is used to receive the control signal of the host computer 34, and respectively control the opening and closing of the first MOS tube 43 and the second MOS tube 45. In this solution, the MOS tube has three terminals, which are divided into a power input terminal connected to the DC power supply 42, a signal control terminal connected to the signal generator, and an output current terminal connected to the coil. The signal at the signal control terminal determines whether the MOS tube is internally conductive, and further determines whether the output current terminal outputs current; the signal generator 41 can transmit the control signal of the host computer 34, and provide signals of different parameters as the switch control signals of the first MOS tube 43 and the second MOS tube 45; and provide currents of different amplitudes through the DC power supply 42 to respectively control the magnitude of the output current of the first MOS tube 43 and the second MOS tube 45.

[0059] In order to monitor the change of the pulling force given to the hydrostatic bearing 22 by the two coils, the first actuator assembly 44 further includes a first fixing block 441, a first force sensor 442 and a first iron core 443. The first fixing block 441 is fixed on the stator of the hydrostatic bearing 22. The first fixing block 441 is connected to the first iron core 443 through the first force sensor 442. The first iron core 443 is located on the side of the first coil 444 away from the hydrostatic bearing 22.

[0060] The second actuator assembly 46 further includes a second fixed block 461, a second force sensor 462, and a second iron core 463. The second fixed block 461 is fixed on the stator of the hydrostatic bearing 22. The second fixed block 461 is connected to the second iron core 463 through the second force sensor 462. The second iron core 463 is located on the side of the second coil 464 away from the hydrostatic bearing 22. In this solution, the iron core is placed on the side of the coil away from the hydrostatic bearing 22, so that tension is applied to the iron core. The iron core is fixed on the fixed block through the force sensor, and the change in tension can be monitored through the force sensor to improve control accuracy.

[0061] To achieve detachable connection of the force sensor, both sides of the first force sensor 442 and the second force sensor 462 are threaded, and the two ends of the first force sensor 442 are threadedly connected to the first fixing block 441 and the first iron core 443 respectively, and the two ends of the second force sensor 462 are threadedly connected to the second fixing block 461 and the second iron core 463 respectively.

[0062] Embodiment 2:

[0063] This embodiment 2 is further optimized on the basis of embodiment 1, such as Figure 4 As shown, a control method of a hydrostatic bearing 22 rotation accuracy control system is also provided, including the following specific working principles:

[0064] First, the hydrostatic bearing 22 to be tested is detachably mounted on the bearing bracket 23, and the bearing bracket 23 is fixed on the optical platform 1 through a pressure plate; the standard ball 21 is detachably integrated on the rotor of the hydrostatic bearing 22 to be tested; when measuring the rotor displacement of the hydrostatic bearing 22, the high-precision standard ball 21 is used as the target of the sensor, which can effectively reduce the interference of the roundness error of the target on the measurement data. Then, the sensor fixture 32 is detachably mounted on the stator of the hydrostatic bearing 22 to be tested; the displacement sensor 31 is detachably mounted in the sensor fixture 32; the first force sensor 442 is used to fix the first fixed block 441 and the first iron core 443 with its own thread; the second force sensor 462 is used to fix the second fixed block 461 and the second iron core 463 with its own thread; then, the first fixed block 441 and the second fixed block 461 are fixed to the stator of the hydrostatic bearing 22 to be tested by screws; the two pairs of output ends of the DC power supply 42 are connected to the positive and negative power supply electrodes of the first MOS tube 43 and the second MOS tube 45 respectively by wires; the two pairs of output ends of the signal generator 41 are connected to the positive and negative signal control ends of the first MOS tube 43 and the second MOS tube 45 respectively by wires; the positive and negative output ends of the first MOS tube 43 and the second MOS tube 45 are connected to the positive and negative electrodes of the first coil 444 and the second coil 464 respectively by wires.

[0065] After the above installation steps are completed, prepare to start the signal generator 41 and the DC power supply 42 to start regulation; first, the original axis of the hydrostatic bearing 22 and the center coordinates of the standard ball 21 are located by the displacement sensor 31; so as to detect the deviation direction and size according to the original axis.

[0066] The rotor of the static pressure bearing 22 is driven to rotate by a driver;

[0067] Then, the DC power supply 42 is turned on to supply current to the first MOS transistor 43 and the second MOS transistor 45 .

[0068] The displacement sensor 31 collects the movement trajectories of several circles of the center of the standard ball 21 in real time, and transmits the data to the host computer 34 .

[0069] The host computer 34 calculates the center coordinate value of each circle and takes the average of several center coordinate values; then the average is compared with the original axis of the standard ball 21 to obtain the deviation direction and deviation size.

[0070] When the mover of the hydrostatic bearing 22 rotates to the deviation direction and is located in the same plane as the first coil 444 and the second coil 464, the DC power supply 42 is controlled by the upper computer 34 to change the supply current to the first coil 444 or the second coil 464 according to the deviation size; the first MOS tube and the second MOS tube are turned on, and current is output to the first coil 444 and the second coil 464 through the first MOS tube and the second MOS tube, thereby pulling back the mover of the hydrostatic bearing 22 through electromagnetic force.

[0071] The above scheme can pull back the mover of the static pressure bearing 22 through the traction of electromagnetic force, thereby improving the rotation accuracy of the static pressure bearing 22.

[0072] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A hydrostatic bearing rotation accuracy control system, characterized in that: include: A module to be tested (2), the module to be tested (2) comprising a bearing bracket (23) and a standard ball (21), the bearing bracket (23) being used to fix the stator of a hydrostatic bearing (22), the standard ball (21) being coaxially connected to the rotor of the hydrostatic bearing (22) via a rod; A rotation accuracy measurement module (3), the rotation accuracy measurement module (3) comprising a displacement sensor (31) and a host computer (34), the displacement sensor (31) being arranged on one side of the standard ball (21) and being used to detect the displacement of the standard ball (21); A rotation precision control module (4), the rotation precision control module (4) comprising a direct current power supply (42), a first actuator assembly (44) and a second actuator assembly (46), the first actuator assembly (44) comprising a first coil (444), the second actuator assembly (46) comprising a second coil (464), the first coil (444) and the second coil (464) being arranged on both sides of the static pressure bearing (22) and outputting a positive current and a negative current respectively; the direct current power supply (42) supplies current to the first coil (444) and the second coil (464) respectively through two pairs of output terminals; The host computer (34) is used to respectively adjust the output current magnitudes of the two output ends of the direct current power supply (42) according to the detection data of the displacement sensor (31).

2. A hydrostatic bearing rotation accuracy control system according to claim 1, characterized in that: The bearing support (23) comprises a top ring plate and a bottom ring plate, wherein the diameter of the top ring plate is smaller than the diameter of the bottom ring plate; the circumferential end of the top ring plate is connected to the circumferential end of the bottom ring plate via a plurality of support rods; The stator of the static pressure bearing (22) and the center hole of the top ring plate are coaxially detachably connected.

3. The hydrostatic bearing rotation accuracy control system according to claim 1, characterized in that: It also includes an optical platform (1), the bearing bracket (23) is detachably connected to the optical platform (1), and the optical platform (1) is provided with an air spring.

4. The hydrostatic bearing rotation accuracy control system according to claim 1, characterized in that: The rotation accuracy measurement module (3) further comprises a sensor fixture (32) and a data acquisition box (33); the sensor fixture (32) is detachably connected to the stator of the static pressure bearing (22); The sensor fixture (32) is used to clamp the displacement sensor (31); The data acquisition box (33) is used to collect data from the displacement sensor (31) and transmit the data to the host computer (34).

5. The hydrostatic bearing rotation accuracy control system according to claim 4, characterized in that: A U-shaped plate is also fixed on the bearing bracket (23), and the U-shaped plate is inverted on the stator of the static pressure bearing (22); a through hole is opened on the upper surface of the U-shaped plate for the standard ball (21) to pass through; and the sensor fixture (32) is fixed on the upper surface of the U-shaped plate.

6. The hydrostatic bearing rotation accuracy control system according to claim 1, characterized in that: The rotation accuracy control module (4) further comprises a first MOS transistor (43), a second MOS transistor (45) and a signal generator (41); a pair of output ends of the DC power supply (42) are connected to the positive and negative electrodes of the power supply of the first MOS transistor (43), and are connected to the first coil (444) through the first MOS transistor (43); another pair of output ends of the DC power supply (42) are connected to the positive and negative electrodes of the power supply of the second MOS transistor (45), and are connected to the second coil (464) through the second MOS transistor (45).

7. A hydrostatic bearing rotation accuracy control system according to claim 6, characterized in that: The rotation accuracy control module (4) further comprises a signal generator (41), wherein two pairs of output ends of the signal generator (41) are respectively connected to the positive and negative electrodes of the signal control ends of the first MOS tube (43) and the second MOS tube (45); The signal generator (41) is used to receive a control signal from the host computer (34) and to control the opening and closing of the first MOS tube (43) and the second MOS tube (45).

8. The hydrostatic bearing rotation accuracy control system according to claim 1, characterized in that: The first actuator assembly (44) further comprises a first fixed block (441), a first force sensor (442) and a first iron core (443), wherein the first fixed block (441) is fixed on the stator of the hydrostatic bearing (22), the first fixed block (441) is connected to the first iron core (443) via the first force sensor (442), and the first iron core (443) is located on a side of the first coil (444) away from the hydrostatic bearing (22); The second actuator assembly (46) further comprises a second fixed block (461), a second force sensor (462) and a second iron core (463), wherein the second fixed block (461) is fixed on the stator of the hydrostatic bearing (22), the second fixed block (461) is connected to the second iron core (463) via the second force sensor (462), and the second iron core (463) is located on a side of the second coil (464) away from the hydrostatic bearing (22).

9. The hydrostatic bearing rotation accuracy control system according to claim 8, characterized in that: Both sides of the first force sensor (442) and the second force sensor (462) are threaded, and the two ends of the first force sensor (442) are respectively threadedly connected to the first fixing block (441) and the first iron core (443), and the two ends of the second force sensor (462) are respectively threadedly connected to the second fixing block (461) and the second iron core (463).

10. A control method for a hydrostatic bearing rotation accuracy control system according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1: locating the original axis of the hydrostatic bearing (22) and the spherical center coordinates of the standard sphere (21) by means of a displacement sensor (31); S2: driving the rotor of the hydrostatic bearing (22) to rotate via a driver; S3: Turning on the DC power supply (42) and supplying current to the first MOS transistor (43) and the second MOS transistor (45); S4: collecting several circles of movement tracks of the center of the standard ball (21) through a displacement sensor (31), and transmitting the data to a host computer (34); S5: the host computer (34) calculates the center coordinate value of each circle and takes the average of several center coordinate values; then compares the average with the original axis of the standard ball (21) to obtain the deviation direction and deviation size; S6: When the mover of the hydrostatic bearing (22) rotates to a deviation direction and is located in the same plane as the first coil (444) and the second coil (464); according to the deviation, the DC power supply (42) is controlled by the host computer (34) to change the supply current to the first coil (444) or the second coil (464); the first MOS tube (43) and the second MOS tube (45) are turned on, and current is output to the first coil (444) and the second coil (464) through the first MOS tube (43) and the second MOS tube (45), so that the mover of the hydrostatic bearing (22) is pulled back by electromagnetic force.

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