An experimental device for non-disturbance measurement of gas static pressure spindle air film velocity field

Abstract

The invention discloses an experimental device for undisturbed measurement of an air film velocity field of a gas static pressure spindle, comprising a gas static pressure spindle system, a spindle drive system, a FlowMaster test system and an air source system; the gas static pressure spindle system comprises a shaft sleeve assembly sleeved on the outside of the spindle, the shaft sleeve assembly being provided with an axial throttling hole, a radial throttling hole and a plurality of groups of fine holes; the motor rotor of the spindle drive system provides driving force for the spindle of the gas static pressure spindle system; the air source system generates high-pressure gas containing uniform tracer particles, the gas enters the gas static pressure spindle system, and forms a high-pressure air film between the shaft sleeve assembly and the spindle to provide support for the spindle; the laser generator in the FlowMaster test system emits laser to irradiate the surface of the air film, and the CCD camera collects the light of the irradiated surface at high frequency and stores the image; the invention can realize the measurement of the air film velocity field in the gas static pressure spindle, and can draw a cloud diagram of the real-time change of the air film velocity field in the gas static pressure spindle with time.

Description

Technical Field

[0001] The invention relates to a non-disturbance measurement experimental device for a gas static pressure spindle gas film velocity field. Background Art

[0002] Ultra-precision machine tools are important carriers for realizing ultra-precision machining. As the core component of ultra-precision machine tools, the spindle’s design accuracy largely determines the machining accuracy of the designed ultra-precision machine tools. Gas hydrostatic spindles are a type of commonly used spindles used in ultra-precision machine tools. Compared with other types of spindles, an important structural feature of gas hydrostatic spindles is that they use pressure gas film as the working medium, which plays an irreplaceable role in certain special occasions. Gas film flow field analysis is an important part of gas hydrostatic spindle research. The distribution law of gas film flow field has an important influence on the spindle rotation accuracy and static and dynamic characteristics. However, domestic and foreign scholars currently mainly use numerical analysis, finite element simulation and other theoretical and simulation methods to study and analyze the flow field distribution law of gas film, and related experimental research is extremely lacking. Summary of the invention

[0003] In order to achieve undisturbed measurement of the air film velocity field of a gas static pressure spindle and further improve the design level of the gas static pressure spindle, the present invention provides an undisturbed measurement experimental device for the air film velocity field of a gas static pressure spindle with no interference and high reliability.

[0004] The technical solution adopted by the present invention is: a non-disturbance measurement experimental device for gas static pressure spindle air film velocity field, including a gas static pressure spindle system, a spindle drive system, a FlowMaster test system, and a gas source system;

[0005] The gas static pressure spindle system comprises an upper thrust plate, a lower thrust plate, a spindle, a sleeve assembly, an air chamber outer sleeve assembly, and a sleeve fixing sleeve; the upper thrust plate and the lower thrust plate are respectively coaxially sealed and fixedly connected with the upper and lower end surfaces of the spindle, and the three together form a concave cavity for accommodating the sleeve assembly;

[0006] The shaft sleeve assembly includes a radial bearing sleeve and an axial thrust bearing plate, and the upper and lower end surfaces of the radial bearing sleeve are both provided with a slot for installing the axial thrust bearing plate; the shaft sleeve assembly is sleeved on the outside of the main shaft, a cylindrical gap groove is formed between the radial bearing sleeve and the main shaft, and an annular gap groove is formed between the axial thrust bearing plate and the main shaft, and air flows into the cylindrical gap groove and the annular gap groove to form an air film to provide support for the main shaft; a plurality of axial throttling holes and radial throttling holes are arranged through the shaft sleeve assembly, the axial throttling holes are connected with the cylindrical gap groove, and the radial throttling holes are connected with the annular gap groove; the outer wall of the radial bearing sleeve is provided with a groove for accommodating the air chamber sleeve assembly, the air chamber sleeve assembly is sleeved on the outside of the shaft sleeve assembly, and the upper and lower groove walls of the groove are sealed and connected with the upper and lower end surfaces of the air chamber sleeve assembly; the gap between the air chamber sleeve assembly and the shaft sleeve assembly forms an air cavity, and the air cavity is connected with the air film through the axial throttling hole and the radial throttling hole; the air chamber sleeve assembly is also provided with an air inlet hole, which is connected with the air cavity;

[0007] The shaft sleeve assembly is provided with a plurality of groups of fine holes along the same radial cross section, and the wall surface of the air chamber outer sleeve assembly is provided with mounting through holes corresponding to the positions of the plurality of groups of fine holes one by one; each group of fine holes includes two fine holes, and the two fine holes are respectively inserted with corresponding linear laser generators and CCD cameras from the outside, the head of the laser generator is slightly lower than the inner wall of the shaft sleeve assembly, and the head of the CCD camera extends into the air film; the air chamber outer sleeve assembly and the shaft sleeve assembly are provided with a through hole penetrating the two, and a pin for limiting the axial movement of the air chamber outer sleeve assembly and the shaft sleeve assembly is provided in the through hole; the shaft sleeve fixing sleeve is arranged outside the lower thrust plate but does not contact it, and the lower end surface of the radial bearing sleeve is fixedly connected to the shaft sleeve fixing sleeve;

[0008] The spindle drive system comprises a motor rotor, a motor stator, a motor shaft, a motor rotor fixing baffle, and a motor stator sleeve; the motor stator sleeve is sleeved outside the motor stator, and a step for limiting the axial movement of the motor stator is provided on the inner wall of the motor stator sleeve, and the upper and lower end surfaces of the motor stator sleeve are respectively fixedly connected to the motor stator fixing baffle and the radial bearing sleeve; the motor rotor and the motor stator are arranged correspondingly, the motor rotor is sleeved on the motor shaft, the upper end surfaces of the motor rotor and the motor shaft are both fixedly connected to the motor rotor fixing baffle, and the lower end surface of the motor shaft is fixedly connected to the upper thrust plate;

[0009] The FlowMaster test system includes an array sensor distribution component, an industrial control analysis platform and a signal collector; the array sensor distribution component includes a laser generator and a CCD camera, the laser generator and the CCD camera are connected to the signal collector through a shielded cable, and the signal collector is connected to the industrial control analysis platform;

[0010] The gas source system includes a gas source generator, a gas purification treatment device, a gas tracer particle mixing device, and an air intake head; the air intake hole is provided with an air intake head that matches it, and the air intake head is connected to the gas tracer particle mixing device, the gas purification treatment device, and the gas source generator in sequence through pipelines.

[0011] Furthermore, the air chamber housing assembly is equally divided into a first air chamber housing and a second air chamber housing along the same axial section, and mounting ears are provided on the outer side walls of the first air chamber housing and the second air chamber housing close to the section, and fasteners use the mounting ears to integrate the first air chamber housing and the second air chamber housing into a whole.

[0012] Furthermore, the upper and lower groove walls of the groove are both provided with an annular step, and the contact surface between the step and the outer sleeve assembly of the air chamber is provided with an annular sealing hole, and a sealing member is provided in the sealing hole.

[0013] Furthermore, the shaft sleeve assembly has three radial sections at equal intervals along its axial direction, and the shaft sleeve assembly is provided with four groups of fine holes at equal intervals along its circumferential direction on each radial section.

[0014] Furthermore, the upper thrust plate, main shaft, lower thrust plate, shaft sleeve assembly, and air chamber outer sleeve assembly are all made of 38CrMoAl material.

[0015] The beneficial effects of the present invention are: it can realize the measurement of the air film velocity field in the gas static pressure spindle, and can draw a cloud map of the real-time change of the air film velocity field in the gas static pressure spindle over time; this device is based on Micro-PIV microscopic flow field testing technology, and its measurement accuracy is effectively guaranteed, which can fully meet engineering requirements; the test process is interference-free, highly reliable, and the measurement results are highly credible. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the static pressure main shaft and its transmission structure of the present invention.

[0017] Figure 2 It is a schematic diagram of the test sensing and control process of the present invention.

[0018] Figure 3 It is a schematic diagram of the arrangement of the array type sensor distribution assembly of the present invention.

[0019] Explanation of the accompanying drawings: 1. lower thrust plate; 2. shaft sleeve fixing sleeve; 3. shaft sleeve assembly; 3-01. axial thrust bearing plate; 3-02. radial bearing sleeve; 3-03. axial throttle hole; 3-04. radial throttle hole; 4. air cavity; 5. sealing hole; 6. upper thrust plate; 7. motor stator sleeve; 8. motor stator fixing baffle; 9. motor rotor; 10. motor rotor fixing baffle; 11. motor stator; 12. air chamber housing assembly; 12-01. first air chamber housing; 12-02. second air chamber housing; 13 main shaft; 14. gas source generator; 15. ejector pin; 16. laser generator; 17. CCD camera; 18. industrial control analysis station; 19. signal collector; 20. air intake head; 21. gas tracer particle mixing device; 22. gas purification treatment device. DETAILED DESCRIPTION

[0020] The present invention is further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto:

[0021] Referring to the attached drawings, a non-disturbance measurement experimental device for a gas static pressure spindle gas film velocity field includes a gas static pressure spindle system, a spindle drive system, a FlowMaster test system, and a gas source system;

[0022] The gas static pressure spindle system comprises an upper thrust plate 6, a lower thrust plate 1, a spindle 13, a sleeve assembly 3, an outer sleeve assembly 12 of the gas chamber, and a sleeve fixing sleeve 2; the upper thrust plate 6 and the lower thrust plate 1 are respectively coaxially sealed and fixedly connected with the upper and lower end surfaces of the spindle 13, and the three together form a concave cavity for accommodating the sleeve assembly 3; the sleeve assembly 3 comprises a radial bearing sleeve 3-02 and an axial thrust bearing plate 3-01, and the upper and lower end surfaces of the radial bearing sleeve 3-02 are both provided with a groove for installing the axial thrust bearing plate 3-01 The sleeve assembly 3 is sleeved on the outside of the main shaft, a cylindrical gap groove is formed between the radial bearing sleeve 3-02 and the main shaft 13, an annular gap groove is formed between the axial thrust bearing plate 3-01 and the main shaft 13, and an air film is formed in the cylindrical gap groove and the annular gap groove to provide support for the main shaft 13; a plurality of axial throttling holes 3-03 and radial throttling holes 3-04 are arranged through the sleeve assembly 3, the axial throttling holes 3-03 are connected to the cylindrical gap groove, and the radial throttling holes 3-04 are connected to the annular gap groove;

[0023] The outer wall of the radial bearing sleeve 3-02 is provided with a groove for accommodating the outer sleeve assembly 12. The outer sleeve assembly 12 is sleeved on the outside of the shaft sleeve assembly 3. The upper and lower groove walls of the groove are sealed and connected with the upper and lower end surfaces of the outer sleeve assembly 12; the upper and lower groove walls of the groove are both provided with annular steps, and the contact surface between the step and the outer sleeve assembly 12 is provided with annular sealing holes 5, and a sealing member is provided in the sealing hole 5; the outer sleeve assembly 12 is equally divided into a first outer sleeve 12-01 and a second outer sleeve 12 along the same axial section. -02, and the first air chamber sleeve 12-01 and the second air chamber sleeve 12-02 are provided with mounting ears on the outer side walls close to the cross section, and the fasteners form the first air chamber sleeve 12-01 and the second air chamber sleeve 12-02 into a whole through the mounting ears; the gap between the air chamber sleeve assembly 12 and the shaft sleeve assembly 3 forms an air cavity 4, and the air cavity 4 is connected to the air film through the axial throttle hole 3-03 and the radial throttle hole 3-04; the wall surface of the first air chamber sleeve 12-01 is also provided with an air inlet hole, and the air inlet hole is connected to the air cavity 4;

[0024] The shaft sleeve assembly 3 is provided with four groups of fine holes along the same radial section, and the wall surface of the air chamber sleeve assembly 12 is provided with mounting through holes corresponding to the positions of the four groups of fine holes one by one; each group of fine holes includes two fine holes, and the two fine holes are respectively inserted from the outside into the corresponding linear laser generator 16 and CCD camera 17, the head of the laser generator 16 is slightly lower than the inner wall of the shaft sleeve assembly 3, and the head of the CCD camera 17 extends into the air film; the shaft sleeve assembly 3 has three radial sections with equal spacing along its axial direction, and the shaft sleeve assembly 3 has a plurality of radial sections in each of the sections. The radial cross section is provided with four groups of fine holes at equal intervals along its circumferential direction; the air chamber outer sleeve assembly 12 and the shaft sleeve assembly 3 are provided with a through hole penetrating the two, and a pin 15 is provided in the through hole for limiting the axial movement of the air chamber outer sleeve assembly 12 and the shaft sleeve assembly 3; the shaft sleeve fixing sleeve 2 is sleeved on the outside of the lower thrust plate 1, and the lower end surface of the radial bearing sleeve 3-02 is fixedly connected to the shaft sleeve fixing sleeve 2; the upper thrust plate 6, the main shaft 13, the lower thrust plate 1, the shaft sleeve assembly 3, and the air chamber outer sleeve assembly 12 are all made of 38CrMoAl material;

[0025] The spindle drive system includes a motor rotor 9, a motor stator 11, a motor shaft, a motor rotor fixed baffle 10, and a motor stator sleeve 7; the motor stator sleeve 7 is sleeved outside the motor stator 11, and a step for limiting the axial movement of the motor stator 11 is provided on the inner wall of the motor stator sleeve 7, and the upper and lower end surfaces of the motor stator sleeve 7 are respectively fixedly connected to the motor stator fixed baffle 8 and the radial bearing sleeve 3-02; the motor rotor 9 is arranged corresponding to the motor stator 11, the motor rotor 9 is sleeved on the motor shaft, the upper end surfaces of the motor rotor 9 and the motor shaft are fixedly connected to the motor rotor fixed baffle 10, and the lower end surface of the motor shaft is fixedly connected to the upper thrust plate 6;

[0026] The FlowMaster test system includes an array sensor distribution component, an industrial control analysis table 18 and a signal collector 19; the array sensor distribution component includes a laser generator 16 and a CCD camera 17, the laser generator 16 and the CCD camera 17 are connected to the signal collector 19 through a special shielded cable, and the signal collector 19 is connected to the industrial control analysis table 18;

[0027] The gas source system includes a gas source generator 14, a gas purification treatment device 22, a gas tracer particle mixing device 21, and an air intake head 20; the air intake hole is provided with an air intake head 20 that matches it, and the air intake head 20 is connected to the gas tracer particle mixing device 21, the gas purification treatment device 22, and the gas source generator 14 in sequence through pipelines.

[0028] The concept of the present invention is as follows: when the gas static pressure spindle 13 is working, the gas source system first works and generates high-pressure gas containing uniform tracer particles and being properly processed. After the gas enters the sleeve assembly 3, it passes through the radial throttle hole 3-04 and the axial throttle hole 3-03 on the sleeve assembly 3 to form a high-pressure gas film in the gap between the sleeve assembly 3 and the spindle 13. The high-pressure gas film acts on the spindle 13 to play a role of bearing and lubrication; then the motor shaft is driven to rotate through the frameless motor rotor 9, thereby driving the spindle 13, the upper thrust plate 6 and the lower thrust plate 7 into a high-speed rotation state. The laser generator 16 emits laser light to irradiate the surface of the gas film, and the tracer particles and other gas particles in the flow field show different reflection characteristics. The CCD camera 17 collects the irradiated surface light at high frequency and stores it in the memory. The industrial control analysis station 18 processes the obtained image, and calculates the cross-correlation function of the corresponding small area in the two consecutive images through fast Fourier transform analysis, so as to obtain the average displacement and velocity of the tracer particle image in the two consecutive images. The velocity information of the tracer particles reflects the velocity information of the air film flow field, based on which the distribution law of the air film velocity field can be finally obtained.

[0029] The working principle of image processing, analysis and calculation of the industrial control analysis platform 18 of the present invention adopts the technical solution disclosed in the following reference: Wang Ling, Luo Rui, Wang Buxuan. Research on Micro-PIV three-dimensional measurement image processing and optimization [J]. Thermal Energy and Power Engineering, 2012, 27(4): 442-448.

[0030] The contents described in the embodiments of this specification are merely an enumeration of implementation forms of the inventive concept. The protection scope of the present invention should not be regarded as limited to the specific forms described in the embodiments. The protection scope of the present invention also extends to equivalent technical means that can be conceived by those skilled in the art based on the inventive concept.

Claims

1. An experimental device for non-disturbance measurement of gas static pressure spindle air film velocity field, characterized in that: Including gas static pressure spindle system, spindle drive system, FlowMaster test system, gas source system; The gas static pressure spindle system comprises an upper thrust plate, a lower thrust plate, a spindle, a sleeve assembly, an air chamber outer sleeve assembly, and a sleeve fixing sleeve; the upper thrust plate and the lower thrust plate are respectively coaxially sealed and fixedly connected with the upper and lower end surfaces of the spindle, and the three together form a concave cavity for accommodating the sleeve assembly; The shaft sleeve assembly includes a radial bearing sleeve and an axial thrust bearing plate, and the upper and lower end surfaces of the radial bearing sleeve are both provided with a slot for installing the axial thrust bearing plate; the shaft sleeve assembly is sleeved on the outside of the main shaft, a cylindrical gap groove is formed between the radial bearing sleeve and the main shaft, and an annular gap groove is formed between the axial thrust bearing plate and the main shaft, and air flows into the cylindrical gap groove and the annular gap groove to form an air film to provide support for the main shaft; a plurality of axial throttling holes and radial throttling holes are arranged through the shaft sleeve assembly, the axial throttling holes are connected with the cylindrical gap groove, and the radial throttling holes are connected with the annular gap groove; the outer wall of the radial bearing sleeve is provided with a groove for accommodating the air chamber sleeve assembly, the air chamber sleeve assembly is sleeved on the outside of the shaft sleeve assembly, and the upper and lower groove walls of the groove are sealed and connected with the upper and lower end surfaces of the air chamber sleeve assembly; the gap between the air chamber sleeve assembly and the shaft sleeve assembly forms an air cavity, and the air cavity is connected with the air film through the axial throttling hole and the radial throttling hole; the air chamber sleeve assembly is also provided with an air inlet hole, which is connected with the air cavity; The shaft sleeve assembly is provided with a plurality of groups of fine holes along the same radial cross section, and the wall surface of the air chamber outer sleeve assembly is provided with mounting through holes corresponding to the positions of the plurality of groups of fine holes one by one; each group of fine holes includes two fine holes, and the two fine holes are respectively inserted with corresponding linear laser generators and CCD cameras from the outside, the head of the laser generator is slightly lower than the inner wall of the shaft sleeve assembly, and the head of the CCD camera extends into the air film; the air chamber outer sleeve assembly and the shaft sleeve assembly are provided with a through hole penetrating the two, and a pin for limiting the axial movement of the air chamber outer sleeve assembly and the shaft sleeve assembly is provided in the through hole; the shaft sleeve fixing sleeve is arranged outside the lower thrust plate but does not contact it, and the lower end surface of the radial bearing sleeve is fixedly connected to the shaft sleeve fixing sleeve; The spindle drive system comprises a motor rotor, a motor stator, a motor shaft, a motor rotor fixing baffle, and a motor stator sleeve; the motor stator sleeve is sleeved outside the motor stator, and a step for limiting the axial movement of the motor stator is provided on the inner wall of the motor stator sleeve, and the upper and lower end surfaces of the motor stator sleeve are respectively fixedly connected to the motor stator fixing baffle and the radial bearing sleeve; the motor rotor and the motor stator are arranged correspondingly, the motor rotor is sleeved on the motor shaft, the upper end surfaces of the motor rotor and the motor shaft are both fixedly connected to the motor rotor fixing baffle, and the lower end surface of the motor shaft is fixedly connected to the upper thrust plate; The FlowMaster test system includes an array sensor distribution component, an industrial control analysis platform and a signal collector; the array sensor distribution component includes a laser generator and a CCD camera, the laser generator and the CCD camera are connected to the signal collector through a shielded cable, and the signal collector is connected to the industrial control analysis platform; The gas source system includes a gas source generator, a gas purification treatment device, a gas tracer particle mixing device, and an air inlet head; the air inlet hole is provided with an air inlet head matched therewith, and the air inlet head is sequentially connected to the gas tracer particle mixing device, the gas purification treatment device, and the gas source generator through pipelines; The air chamber housing assembly is equally divided into a first air chamber housing and a second air chamber housing along the same axial section, and mounting ears are provided on the outer side walls of the first air chamber housing and the second air chamber housing close to the section, and the fasteners use the mounting ears to form the first air chamber housing and the second air chamber housing into a whole; The upper and lower groove walls of the groove are both provided with an annular step, and the contact surface between the step and the outer sleeve assembly of the gas chamber is provided with an annular sealing hole, and a sealing member is provided in the sealing hole.

2. The non-disturbance measurement experimental device for the gas static pressure spindle air film velocity field according to claim 1, characterized in that: The shaft sleeve assembly has three radial sections at equal intervals along its axial direction, and the shaft sleeve assembly is provided with four groups of fine holes at equal intervals along its circumferential direction on each radial section.

3. The non-disturbance measurement experimental device for the gas static pressure spindle air film velocity field according to claim 1, characterized in that: The upper thrust plate, the main shaft, the lower thrust plate, the shaft sleeve assembly and the air chamber outer sleeve assembly are all made of 38CrMoAl material.

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