Main shaft bearing lubrication reliability test device and method

Abstract

The invention relates to the technical field of detection equipment, in particular to a spindle bearing lubrication reliability test device and method, and the device comprises a power part for driving the inner and outer rings of a bearing to rotate, a loading part for providing a load for the bearing, and a detection part for detecting the thickness of an oil film in the bearing. The power part comprises a worm and two turbines used in cooperation with the worm, transmission wheels are oppositely arranged on the turbines, the turbines and the transmission wheels are in transmission through transmission shafts, and the two transmission wheels are used for providing rotation power for the inner ring and the outer ring of a bearing respectively. The purpose of testing and detecting the bearing under different working conditions can be achieved by enabling the inner ring and the outer ring of the bearing to move in various forms, the detection accuracy and the test comprehensiveness are effectively improved, the bearing under the different working conditions can be conveniently matched with different lubricating liquid, and the supplementing period of the lubricating liquid under the different working conditions can be conveniently optimized.

Description

Technical Field

[0001] The invention relates to the technical field of detection equipment, and in particular to a spindle bearing lubrication reliability test device and method. Background Art

[0002] With the rapid development of high-end equipment manufacturing industry, electric spindles, core components in the fields of CNC machine tools, aerospace engines, new energy vehicle drive systems, etc., are evolving towards high speed, high precision and high reliability. As the supporting core of the spindle, the lubrication performance of the bearing directly determines the life, energy consumption and operation stability of the spindle.

[0003] The movement forms of bearings in real applications are complex and diverse. The force and movement state of the inner and outer rings directly affect the distribution of the lubricating film, the accumulation of frictional heat and fatigue life. For example, in the main shaft of a wind turbine and the rotor of an aircraft engine, it is mainly the outer ring of the bearing that rotates. In complex transmission systems such as gearboxes and differentials, the inner and outer rings of the bearings generally rotate. In the main shaft of a machine tool, it is mainly the inner ring of the bearing that rotates. Therefore, the detection of the lubricity of the bearing requires multiple forms of detection according to the actual situation. The traditional detection method only detects the inner or outer ring of the bearing. During the detection, the corresponding outer or inner ring of the bearing is fixed. This detection method is relatively one-sided and some problems are concealed. For example, when the outer ring rotates, the centrifugal force has a more significant effect on the migration of the lubricating fluid. The sliding friction between the rolling element and the raceway is aggravated under the differential rotation of the inner and outer rings, which accelerates wear. When the relative motion direction of the inner and outer rings changes, the stress distribution inside the bearing is different. Summary of the invention

[0004] The present invention provides a spindle bearing lubrication reliability test device and method, which can effectively solve the problems in the background technology.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: The spindle bearing lubrication reliability test device comprises a power unit for driving the inner and outer rings of the bearing to rotate, a loading unit for providing a load to the bearing, and a detection unit for detecting the thickness of the oil film in the bearing; The power unit includes a worm and two turbines used in conjunction with the worm, each turbine is provided with a transmission wheel opposite to the other, and the turbine and the transmission wheel are driven by a transmission shaft, and the two transmission wheels are used to provide rotational power to the inner and outer rings of the bearing respectively; The turbine and the worm are meshingly connected or separated from each other, and the power unit further includes a locking portion for fixing the turbine in a separated state.

[0006] In some embodiments of the present invention, the locking portion includes a support platform and a plurality of latching racks mounted on the support platform, and the latching racks are used to engage with the turbine.

[0007] In some embodiments of the present invention, the turbine can move in a direction perpendicular to the axis of the worm and away from the worm.

[0008] In some embodiments of the present invention, a linear guide rail is fixed on the support table, a moving table is slidably arranged on the linear guide rail, the transmission shaft is rotatably installed on the moving table, and a first pushing unit for providing power for the movement of the moving table is arranged on the support table.

[0009] In some embodiments of the present invention, the moving direction of the moving table on the linear guide rail is parallel to the axis of the transmission shaft, and the position of the turbine in the circumferential direction of the worm can be adjusted.

[0010] In some embodiments of the present invention, the power unit further includes two arc-shaped guide rails with opposite directions, and the arc-shaped guide rails are coaxial with the worm, and the support table is slidably installed on the arc-shaped guide rails; Wherein, a second pushing unit is relatively fixed between the two arc-shaped guide rails, two inclined arms are oppositely arranged at the movable end of the second pushing unit, and the two inclined arms are respectively rotatably connected to the two support tables; Wherein, the outer circumferential wall shape of the transmission wheel is an arc surface.

[0011] In some embodiments of the present invention, the experimental device further includes a machine table and a main motor installed on the machine table; A plurality of groups of the power unit, the loading unit and the detection unit are arranged, and the worms in the plurality of groups of power units are coaxial and connected in sequence, and the main motor is used to provide power for the worms.

[0012] In some embodiments of the present invention, the detection unit includes a conductive layer arranged on the outer wall of each transmission wheel and a conductive sheet in sliding contact with the conductive layer, the conductive sheet is fixed on the corresponding moving table, and the two conductive layers are respectively in pressing contact and electrical connection with the inner and outer rings of the bearing, so that a capacitor is formed between the inner and outer rings of the bearing; The detection unit further includes a capacitance detector for detecting the capacitance intensity.

[0013] In some embodiments of the present invention, the loading unit includes a first support frame and a second support frame that can move relative to each other, and rollers are arranged at both ends of the first support frame and both ends of the second support frame, the rollers are used to provide axial load for the bearing, the rollers on the first support frame and the rollers on the second support frame are respectively used to press the inner and outer rings of the bearing, and the first support frame and the second support frame respectively provide moving power through two third pushing units.

[0014] Method for testing lubrication reliability of main shaft bearings, based on the above-mentioned test device for lubrication reliability of main shaft bearings, comprising the following steps: Fix a plurality of bearings on each loading part respectively; Adjust the positions of the two transmission wheels in each power part so that the inner and outer rings of each bearing are in the states of inner ring movement, outer ring movement, same-direction differential movement of the inner and outer rings, and reverse movement of the inner and outer rings respectively; Operate the main motor to make the inner ring and / or outer ring of the corresponding bearing in a rotating state; Supplement lubricating fluid through the pipe body into the gap between the inner and outer rings of each bearing, and the rolling elements carry the lubricating fluid to smear between the inner and outer rings; Apply a load to the bearing by means of the loading part; Apply electricity to the inner and outer rings of the bearing, use the oil film as an electrolyte, and use the detection part to detect the capacitance strength between the inner and outer rings of the bearing, so as to calculate the oil film thickness; When it is necessary to detect different lubricating fluids, the operating states of each bearing are the same, and different lubricating fluids are smeared on each bearing, and the above detection process can be repeated.

[0015] Through the technical solution of the present invention, the following technical effects can be achieved: By making the inner and outer rings of the bearing perform various forms of movement, the purpose of testing and detecting the bearing under different working conditions can be achieved, effectively improving the accuracy of detection and the comprehensiveness of the test, facilitating the matching of different lubricating fluids for the bearing under different working conditions, and facilitating the optimization of the replenishment cycle of the lubricating fluid under different working conditions. Description of the Drawings

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for description in the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0017] Figure 1 is the structural schematic diagram of the present invention; Figure 2 is Figure 1 the exploded structural schematic diagram of; Figure 3 is the structural schematic diagram of the power part in the embodiment of the present invention; Figure 4 is the structural schematic diagram of the arc-shaped guide rail in the embodiment of the present invention; Figure 5 is the schematic diagram of the bearing and its upper structure in the embodiment of the present invention; Figure 6 is the structural schematic diagram of the loading part in the embodiment of the present invention.

[0018] Reference numerals: 100, power unit; 101, worm; 102, turbine; 103, transmission shaft; 104, transmission wheel; 105, support platform; 106, rack; 107, linear guide; 108, moving platform; 109, driving unit 1; 110, arc guide; 111, driving unit 2; 112, inclined arm 200, loading unit; 201, support frame 1; 202, support frame 2; 203, roller; 204, driving unit 3; 205, driving unit 4; 206, side push roller 300, detection unit; 301, conductive layer; 302, conductive sheet; 303, capacitance detector 400, bearing 500, pipe body 600, machine platform; 601, main motor Detailed implementation manners

[0019] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this invention belongs. The terms used in the description of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0021] Embodiment 1 As Figures 1 to 4 shown, the spindle bearing lubrication reliability test device of the present invention includes a power unit 100 for driving the inner and outer rings of the bearing 400 to rotate, a loading unit 200 for providing a load for the bearing 400, and a detection unit 300 for detecting the oil film thickness in the bearing 400; The power unit 100 includes a worm 101 and two turbines 102 that cooperate with the worm 101. Transmission wheels 104 are relatively arranged on each turbine 102, and the turbine 102 and the transmission wheel 104 are driven by a transmission shaft 103. The two transmission wheels 104 are respectively used to provide rotational power for the inner and outer rings of the bearing 400; Wherein, the turbine 102 is meshed or separated from the worm 101, and the power unit 100 further includes a locking unit for fixing the separated turbine 102; In the present invention, the power unit 100 is mainly used to provide different forms of power for the rotation of the inner and outer rings of the bearing 400 so that it can operate in multiple forms. For example, when the worm 101 in the power unit 100 rotates forward, the worm 101 drives the two turbines 102 thereon to rotate forward synchronously. At this time, the two turbines 102 drive the two transmission wheels 104 to rotate forward synchronously through the two transmission shafts 103. The two transmission wheels 104 are respectively located on the outer side and the inner side of the bearing 400, that is, the two transmission wheels 104 are respectively in contact with the outer wall of the outer ring and the inner wall of the inner ring of the bearing 400. Thus, the two transmission wheels 104 drive the inner and outer rings of the bearing 400 to rotate synchronously in the same direction. Since the rotation radii of the inner and outer rings are different, the inner and outer rings perform forward synchronous differential motion, and the rolling elements between the inner and outer rings roll in the raceway; when the worm 101 rotates reversely, the inner and outer rings on the bearing 400 perform reverse synchronous differential motion; when the turbine 102 on the transmission wheel 104 outside the bearing 400 is separated from the worm 101 and the turbine 102 is fixed by the corresponding locking portion, at this time the transmission wheel 104 cannot rotate, and the transmission wheel 104 is still in contact with the outer ring of the bearing 400. The outer ring of the bearing 400 is fixed due to the friction of the transmission wheel 104, and the inner ring of the bearing 400 rotates, and the rotation direction of the inner ring is restricted by the rotation direction of the worm 101, that is, at this time the bearing 400 only performs the test detection work of the inner ring rotation, and the inner ring can rotate forward or backward; when the turbine 102 on the transmission wheel 104 inside the bearing 400 is separated from the worm 101, the corresponding locking portion fixes the turbine 102. At this time, the bearing 400 only performs the test detection work of the outer ring rotation, and the outer ring can rotate forward or backward; based on the above content, multiple forms of motion modes of the inner and outer rings of the bearing 400 can be realized; in some embodiments, the two turbines 102 can also be arranged on the same side of the worm 101, so that the two turbines 102 can rotate in the same direction. Together with the transmission shafts 103 and the transmission wheels 104, the two transmission wheels 104 can be made to rotate in the same direction. Since the two transmission wheels 104 act on the inner and outer rings of the bearing 400 respectively, the motion directions of the inner and outer rings on the bearing 400 can be made opposite. Of course, for convenient kinetic energy transmission, multiple transmission shafts 103 and multiple couplings can be used to adjust the kinetic energy transmission direction; Since the transmission wheel 104 thereon needs to maintain a contact state with the inner or outer ring of the bearing 400 when the turbine 102 moves, the moving distance of the turbine 102 or the width of the transmission wheel 104 can be set. When the turbine 102 is separated from the worm 101, the transmission wheel 104 maintains a contact state with the bearing 400; of course, in some embodiments, the position of the transmission wheel 104 can also be relatively fixed, the transmission shaft 103 is in the form of a telescopic rod, and the fixed end of the telescopic rod is connected to the transmission wheel 104, and the movable end of the telescopic rod is connected to the turbine 102. Thus, when the turbine 102 moves, the position of the transmission wheel 104 remains unchanged; The loading part 200 is mainly used to provide a load for the bearing 400, enabling the bearing 400 to simulate normal usage during the test, so as to improve the accuracy of the test; the loading part 200 can provide loads for the bearing 400 in the radial and axial directions of the bearing 400; the detection part 300 is used to detect the oil film thickness inside the bearing 400 to detect the reliability of the lubricating fluid; of course, during some tests, multiple bearings 400 of the same specification can be used in combination with different lubricating fluids to detect the lubrication effect and reliability of different lubricating fluids under different usage conditions of the bearing 400; During use, the bearing 400 is fixed on the loading part 200, and the lubricating fluid is injected into the bearing 400 through the pipe body 500. During the injection process, the bearing 400 can be in a rotating state to facilitate the rolling elements to carry the lubricating fluid and smear it on the raceway, or the manual smearing method can also be used. When the two transmission wheels 104 are in contact with the inner and outer rings of the bearing 400 respectively, when the worm 101 operates, it will drive the inner and outer rings of the bearing 400 to operate through the two turbines 102 and the two transmission wheels 104. Then, the loading part 200 provides a load for the bearing 400 to make the bearing 400 simulate the real usage situation. The detection part 300 detects the oil film thickness inside the bearing 400. As the running time of the bearing 400 extends, the oil film thickness gradually decreases, thereby realizing the reliability detection of the oil film of the bearing 400; based on the multiple forms of movement of the bearing 400, various reliability test detections can be realized, thereby improving the comprehensiveness of the detection, and it is convenient to select different lubricating fluids according to different usage environments of the bearing 400; It should be noted that by using the above detections, the consumption cycle of the lubricating fluid can be accurately evaluated, thus facilitating the adjustment and optimization of the lubricating fluid replenishment cycle; since in actual use, factors such as temperature and vibration have a greater impact on the oil film, during the test, supporting auxiliary equipment such as a thermometer, an oscillation detector, and a central control box can be installed to improve the detection accuracy and convenience; of course, if it is necessary to detect the lubricating fluid during or after the test, the lubricating fluid can also be sampled through a straw, a scraper, etc. for subsequent analysis; the contact position of the transmission wheel 104 on the inner side of the bearing 400 with the inner ring can be located near the outer transmission wheel 104 or far from the outer transmission wheel 104, or any other position on the inner ring, as long as it can achieve power transmission; To improve the comprehensiveness of the detection, when abnormal phenomena such as abnormal temperature rise and abnormal vibration of the bearing 400 are detected, its lubrication fails. When the bearing 400 sheds metal debris, there is abnormal wear inside the bearing 400, and the bearing 400 can be judged to have fatigue failure; By enabling various forms of movement of the inner and outer rings of the bearing 400, the purpose of testing and detecting the bearing 400 under different working conditions can be achieved, effectively improving the accuracy of detection and the comprehensiveness of the test, facilitating the matching of different lubricating fluids for the bearing 400 under different working conditions, and optimizing the replenishment cycle of the lubricating fluid under different working conditions; for phenomena such as the influence of centrifugal force on the migration of the lubricating fluid when the outer ring of the bearing 400 rotates, the increased slip friction between the rolling elements and the raceways under differential rotation of the inner and outer rings, accelerating wear, and the difference in the internal stress distribution of the bearing when the relative movement direction of the inner and outer rings changes, different types of lubricating fluids can be specifically selected to solve or improve the above problems or phenomena and extend the service life of the bearing.

[0022] Based on the above implementation, as Figure 4 shown, the locking part includes a support table 105 and a number of rack teeth 106 installed on the support table 105, and the rack teeth 106 are used to mesh with the turbine 102; When the turbine 102 moves, the rack teeth 106 are located on its moving path, so that the teeth on the turbine 102 can mesh with the teeth on the rack teeth 106. At this time, the rack teeth 106 can achieve a blocking effect on the turbine 102; since the teeth on the turbine 102 are spiral teeth, the corresponding teeth on the rack teeth 106 are also spiral teeth; to facilitate the smooth meshing of the turbine 102 and the rack teeth 106, the ends of the spiral teeth on the turbine 102 facing the rack teeth 106 and the ends of the spiral teeth on the rack teeth 106 facing the turbine 102 can both be set to be conical to facilitate the smooth insertion of the turbine 102 and the rack teeth 106.

[0023] Since when the turbine 102 is separated from the worm 101, it only needs to ensure that the turbine 102 is disengaged from the transmission relationship with the worm 101 and the transmission wheel 104 remains in contact with the bearing 400, the moving direction of the turbine 102 can be not limited, that is, the turbine 102 can move in a direction perpendicular to the axis of the worm 101 and away from the worm 101; the specific moving mode of the turbine 102 can be moving along the axis direction of the transmission shaft 103, or moving in a direction perpendicular to the axis of the transmission shaft 103 and the axis of the worm 101, or moving in a direction perpendicular to the axis of the worm 101 and inclined relative to the axis of the transmission shaft 103, as long as the turbine 102 can be smoothly separated from the worm 101 and can be smoothly re-engaged; since the moving direction of the turbine 102 can be selected in multiple directions, the position of the rack teeth 106 needs to be adjusted accordingly and correspond to the turbine 102.

[0024] Based on the above implementation, as Figure 4 shown, a linear guide rail 107 is fixed on the support table 105, a moving table 108 is slidably arranged on the linear guide rail 107, the transmission shaft 103 is rotatably installed on the moving table 108, and a driving unit one 109 for providing power for the movement of the moving table 108 is arranged on the support table 105; The support platform 105 can provide support for the linear guide rail 107. The linear guide rail 107 is used to provide support and guidance for the moving platform 108. The moving platform 108 is used to provide support for the transmission shaft 103. The driving unit one 109 is used to provide power for the movement of the moving platform 108. Thus, the purpose of providing guidance and power for the movement of the turbine 102 can be achieved; In some embodiments, when the transmission shaft 103 is a telescopic rod-like structure, its fixed end can be relatively fixed to the linear guide rail 107, and its movable end can pass through the moving platform 108 and be connected to the turbine 102. Of course, it can also be adopted as Figure 4 shown in the figure, the transmission shaft 103 is directly installed on the moving platform 108, and the transmission wheel 104 is allowed to be able to move synchronously with the turbine 102, but it is necessary to keep the transmission wheel 104 in contact transmission state with the bearing 400 all the time.

[0025] Due to the different specifications of the main shaft, there are also various specifications of the bearing 400. When testing and detecting different bearings 400, the distance between the two transmission wheels 104 needs to have an adjustable function, that is, the moving direction of the moving platform 108 on the linear guide rail 107 is parallel to the axis of the transmission shaft 103, and the position of the turbine 102 in the circumferential direction of the worm 101 can be adjusted; When the turbine 102 moves in the circumferential direction of the worm 101, the structures such as the support platform 105, the rack 106, the linear guide rail 107, the moving platform 108, and the transmission wheel 104 corresponding to the turbine 102 will all move synchronously. At this time, the distance between the two transmission wheels 104 changes, and the turbine 102 and the worm 101 can maintain a meshing relationship, thereby improving the functionality of the test and detection; in order to enable the turbine 102 to move around the circumferential direction of the worm 101 and also to separate from the worm 101, it is necessary to limit the moving direction of the turbine 102 when it separates from the worm 101, and the turbine 102 cannot move randomly. Therefore, the turbine 102 can only move along the axis direction of the transmission shaft 103.

[0026] Based on the above implementation, as Figure 4 shown in the figure, the power unit 100 further includes two arc-shaped guide rails 110 with opposite directions, and the arc-shaped guide rails 110 are coaxial with the worm 101. The support platform 105 is slidably installed on the arc-shaped guide rails 110; Among them, a driving unit two 111 is relatively fixed between the two arc-shaped guide rails 110. The movable ends of the driving unit two 111 are relatively provided with two inclined arms 112, and the two inclined arms 112 are respectively rotatably connected to the two support platforms 105; Among them, the circumferential outer wall shape of the transmission wheel 104 is an arc surface; Since the arc-shaped guide rail 110 is coaxial with the worm 101, when the support table 105 moves, it moves circumferentially around the worm 101. As a result, the turbine 102 can move circumferentially around the worm 101, and the movement of the support table 105 does not affect the sliding of the moving table 108 on the linear guide rail 107, so that the turbine 102 can also meet the design requirement of being separated from the worm 101; when transmitting different specifications of bearings 400, at least one of the two transmission wheels 104 generates displacement, that is, either transmission wheel 104 is allowed to move to adjust the distance between the two transmission wheels 104, or both transmission wheels 104 are allowed to move to adjust the distance between the two transmission wheels 104. When both transmission wheels 104 are allowed to move, the moving distance of each transmission wheel 104 can be smaller than the distance when only one transmission wheel 104 moves, thereby increasing the adjustment range. To keep the two transmission wheels 104 at the same height position, the two support tables 105 need to move synchronously. By setting the pushing unit two 111 and the two inclined arms 112, the synchronous movement effect of the two support tables 105 can be achieved; Since the turbine 102 and the support table 105 can move circumferentially around the worm 101, the transmission wheel 104 may be inclined relative to the bearing 400. To enable the transmission wheel 104 to maintain a stable contact transmission effect with the bearing 400, the circumferential outer wall of the transmission wheel 104 can be set as an arc surface.

[0027] Optimized based on the above implementation, the experimental device further includes a machine table 600 and a main motor 601 installed on the machine table 600; Multiple groups of the power unit 100, the loading unit 200, and the detection unit 300 are arranged, and the worms 101 in the multiple groups of power units 100 are coaxially arranged and connected in sequence. The main motor 601 is used to provide power for the worm 101; In the present invention, the machine platform 600 can provide an installation position for the test device, and the main motor 601 can provide power for a plurality of worm gears 101 arranged in sequence, so as to enable the plurality of worm gears 101 to move synchronously, achieving the effect of simultaneously detecting a plurality of bearings 400; when it is necessary to detect different lubricating fluids, a plurality of bearings 400 of the same specification can be selected and assembled onto a plurality of loading parts 200 simultaneously for testing. In this way, the reliability of different lubricating fluids can be directly detected at the same time, instead of only being able to detect one bearing 400 and one lubricating fluid each time as in the traditional method. This simultaneous detection method can make the comparison of detection data more intuitive and accurate, without the need to repeatedly record data, and during the detection process, it is possible to make a quick judgment according to the consumption situation of different lubricating fluids, without the need for a long-term test. That is, this comparison and synchronous detection method can directly make a judgment according to the lubricating fluid consumption trend and comparison within a certain period of time. This can not only shorten the time for simultaneous detection of a plurality of bearings 400, but also shorten the time in the detection cycle; of course, in some embodiments, in order to detect the reliability of a single lubricating fluid, a long-term test is required, and it can also be implemented in the present invention.

[0028] When detecting the oil film thickness, the common methods are to stop the machine for detection, or to use the method of current breakdown of the oil film for non-stop detection. However, the first method mentioned above will cause the test to be interrupted, and the second method will cause electrical shock loss of the oil film, affecting the test accuracy. Therefore, in order to achieve the detection of the oil film thickness without stopping the machine and protecting the oil film, the capacitance method can be adopted. Specifically, as Figures 4 to 5 shown, the detection part 300 includes a conductive layer 301 provided on the outer wall of each driving wheel 104 and a conductive piece 302 in sliding contact with the conductive layer 301. The conductive piece 302 is fixed to the corresponding moving table 108. The two conductive layers 301 are respectively in extrusion contact and electrically connected to the inner and outer rings of the bearing 400, so as to form a capacitance between the inner and outer rings of the bearing 400; The detection part 300 further includes a capacitance detector 303 for detecting the capacitance intensity; In the present invention, the conductive layer 301 can be directly wrapped on the driving wheel 104, or the driving wheel 104 can be made to have a wire shape by means of depositing or smearing conductive metal. The conductive piece 302 is fixed on the moving table 108, and the conductive piece 302 needs to be in contact with the conductive layer 301, so that the conductive layer 301 can be connected to an external power source to realize the power supply work for the conductive layer 301. When the conductive layers 301 on the two driving wheels 104 respectively supply power to the inner and outer rings of the bearing 400, an electric field is formed between the inner and outer rings of the bearing 400, that is, a capacitance structure is formed between the inner and outer rings of the bearing 400. Then, the capacitance detector 303 is used to detect the capacitance value, so as to realize the detection work of the oil film thickness; It should be noted that due to the presence of rolling elements, the current will flow through the rolling elements, thus destroying the capacitance structure formed by the inner and outer rings. At this time, an insulating layer can be applied to the rolling elements and raceways to isolate the current, or a high-frequency excitation method can be adopted, using high-frequency alternating current, and the "skin effect" of the conductor is utilized to reduce the conduction of the current by the rolling elements, that is, at high frequencies, the current is concentrated on the surface of the conductor, the actual conduction cross-sectional area of the rolling elements is small, and the impedance increases, thereby realizing the detection of the oil film thickness. Of course, the oil film thickness can also be calculated by means of compensation according to the alternating current frequency.

[0029] Optimized based on the above implementation, as Figures 5 to 6 shown, the loading part 200 includes a support frame one 201 and a support frame two 202 that can move relative to each other, and rollers 203 are provided at both ends of the support frame one 201 and both ends of the support frame two 202. The rollers 203 are used to provide axial load for the bearing 400. The rollers 203 on the support frame one 201 and the rollers 203 on the support frame two 202 are respectively used to extrude the inner and outer rings of the bearing 400, and the support frame one 201 and the support frame two 202 respectively provide moving power through two pushing units three 204; In the present invention, the above structure provides axial load, that is, when one pushing unit three 204 extends and the other pushing unit three 204 shortens, the rollers 203 on the relative support frame one 201 act on the outer ring of the bearing 400, and the rollers 203 on the support frame two 202 act on the inner ring of the bearing 400, and the forces on the inner and outer rings are opposite, so as to achieve the purpose of providing axial load for the bearing; In actual use, the distance between the two rollers 203 on the support frame one 201 or the support frame two 202 will be greater than the thickness of the bearing 400, which can facilitate the bearing 400 to enter between the support frame one 201 and the support frame two 202 smoothly. When it is necessary to fix the bearing 400, one pushing unit three 204 can be extended and the other pushing unit three 204 can be shortened, so that the support frame one 201 and the support frame two 202 can move alternately and use the corresponding rollers 203 to achieve the extrusion and fixing effect on the inner and outer rings of the bearing; In some embodiments, since the bearing 400 needs to bear radial load, the loading part 200 can further include a pushing unit four 205 and a side push roller 206 for providing radial load for the bearing 400. The side push roller 206 is installed at the movable end of the pushing unit four 205. The pushing unit four 205 can push the side push roller 206 to act on the outer ring or the inner ring of the bearing 400, so as to Figure 5 take as an example, the side push roller 206 acts on the outer ring of the bearing 400; The pushing unit three 204 and the pushing unit four 205 are both fixed relative to the machine table 600.

[0030] Embodiment 2 Method for testing lubrication reliability of main shaft bearings, based on the above-mentioned test device for lubrication reliability of main shaft bearings, includes the following steps: Fix a plurality of bearings 400 on each loading part 200 respectively; Adjust the positions of the two transmission wheels 104 in each power part 100 so that the inner and outer rings of each bearing 400 are in the states of inner ring movement, outer ring movement, same-direction differential movement of the inner and outer rings, and reverse movement of the inner and outer rings respectively; Operate the main motor 601 to make the inner ring and / or outer ring of the corresponding bearing 400 in a rotating state; Supplement lubricating fluid into the gap between the inner and outer rings of each bearing 400 through the pipe body 500, and the rolling elements carry the lubricating fluid to smear between the inner and outer rings; Apply a load to the bearing 400 by using the loading part 200; Apply electricity to the inner and outer rings of the bearing 400, take the oil film as the electrolyte, and use the detection part 300 to detect the capacitance strength between the inner and outer rings of the bearing 400, so as to calculate the oil film thickness; When it is necessary to detect different lubricating fluids, the operating states of each bearing 400 are the same, and different lubricating fluids are smeared on each bearing 400, and the above detection process can be repeated; By using the above method, the oil film reliability test of the bearing 400 under different working conditions can be realized, and the reliability detection of different oil films can also be realized. Compared with the traditional method, the detection is more comprehensive and the accuracy is higher.

[0031] It should be noted that each driving unit in this case can be any structure such as a cylinder, an oil cylinder, an electromagnetic thruster, a propulsion motor, etc., which can be selected according to the assembly requirements, and the structural dimensions, specifications, strength, materials, etc. in this case can all be determined according to actual needs, which will not be elaborated here.

[0032] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. Spindle bearing lubrication reliability test device, characterized in that, It includes a power unit for driving the inner and outer rings of the bearing to rotate, a loading unit for applying load to the bearing, and a detection unit for detecting the oil film thickness inside the bearing; The power unit includes a worm and two turbines that cooperate with the worm. Transmission wheels are oppositely arranged on each turbine, and the turbine and the transmission wheel are driven by a transmission shaft. The two transmission wheels are respectively used to provide rotational power to the inner and outer rings of the bearing; Among them, the turbine is meshed or separated from the worm, and the power unit further includes a locking unit for fixing the separated turbine.

2. The spindle bearing lubrication reliability test device according to claim 1, characterized in that The locking unit includes a support platform and a plurality of rack teeth installed on the support platform. The rack teeth are used to mesh with the turbine.

3. The spindle bearing lubrication reliability test device according to claim 1, characterized in that The turbine can move in a direction perpendicular to the axis of the worm and away from the worm.

4. The spindle bearing lubrication reliability test device according to claim 2, characterized in that, A linear guide rail is fixed on the support platform. A moving platform is slidably arranged on the linear guide rail. The transmission shaft is rotatably installed on the moving platform. A first pushing unit for providing power for the movement of the moving platform is arranged on the support platform.

5. The spindle bearing lubrication reliability test device according to claim 4, characterized in that, The moving direction of the moving platform on the linear guide rail is parallel to the axis of the transmission shaft, and the position of the turbine in the circumferential direction of the worm can be adjusted.

6. The spindle bearing lubrication reliability test device according to claim 5, characterized in that The power unit further includes two arc-shaped guide rails with opposite directions, and the arc-shaped guide rails are coaxial with the worm. The support platform is slidably installed on the arc-shaped guide rail; Among them, a second pushing unit is relatively fixed between the two arc-shaped guide rails. The movable ends of the second pushing unit are oppositely provided with two inclined arms, and the two inclined arms are respectively rotatably connected to the two support platforms; Among them, the circumferential outer wall shape of the transmission wheel is an arc surface.

7. The spindle bearing lubrication reliability test device according to claim 6, characterized in that, The experimental device further includes a machine table and a main motor installed on the machine table; Multiple groups of the power unit, the loading unit, and the detection unit are arranged. The worms in multiple groups of power units are coaxially arranged and connected in sequence. The main motor is used to provide power for the worm.

8. The spindle bearing lubrication reliability test device according to claim 4, characterized in that, The detection unit includes a conductive layer arranged on the outer wall of each transmission wheel and a conductive sheet that slidably contacts the conductive layer. The conductive sheet is fixed on the corresponding moving platform. The two conductive layers are respectively in pressing contact and electrically connected to the inner and outer rings of the bearing, so as to form a capacitor between the inner and outer rings of the bearing; The detection unit further includes a capacitance detector for detecting the capacitance intensity.

9. The spindle bearing lubrication reliability test device according to claim 1, characterized in that, The loading unit includes a support frame one and a support frame two that can move relative to each other. Rollers are arranged at both ends of the support frame one and both ends of the support frame two. The rollers are used to provide axial load for the bearing. The rollers on the support frame one and the rollers on the support frame two are respectively used to press the inner and outer rings of the bearing. The support frame one and the support frame two are respectively provided with a third pushing unit to provide moving power.

10. A test method for the lubrication reliability of a spindle bearing, applicable to the test device for the lubrication reliability of the spindle bearing according to any one of claims 1-9, characterized in that, It includes the following steps: Fix multiple bearings on each loading unit respectively; Adjust the positions of the two transmission wheels in each power unit so that the inner and outer rings of each bearing are in the states of inner ring movement, outer ring movement, same-direction differential movement of the inner and outer rings, and reverse movement of the inner and outer rings respectively; Run the main motor to make the inner ring and / or outer ring of the corresponding bearing in a rotating state; Supplement lubricating fluid into the gap between the inner and outer rings of each bearing through the pipe body, and the rolling elements carry the lubricating fluid and smear it between the inner and outer rings; Apply a load to the bearing using the loading part; Apply electricity to the inner and outer rings of the bearing. Taking the oil film as the electrolyte, use the detection part to detect the capacitance strength between the inner and outer rings of the bearing, and thus calculate the oil film thickness; When it is necessary to detect different lubricating fluids, the operating states of each bearing are the same, and different lubricating fluids are smeared on each bearing, and the above detection process can be repeated.

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