Testing device for self-pre-tightening back-to-back paired angular contact ball bearings

Abstract

The utility model relates to the field of bearing processing, and particularly discloses a testing device for self-pretightening back-to-back paired angular contact ball bearings. The testing device comprises an outer ring mounting assembly, an inner ring clamping assembly and a torque measuring assembly, the outer ring mounting assembly comprises a test mounting seat and a test load block, the top surface of the test mounting seat is an outer ring bearing surface, and the test load block is provided with an outer ring loading surface; in a test state, the test load block is positioned above the test mounting seat, and an outer ring mounting interval is formed between the outer ring loading surface and the outer ring bearing surface; according to the testing device, the starting torque of the bearing can be measured, the machining quality of the bearing is judged by starting torque measurement instead of pre-tightening force measurement, and efficient and reliable production of back-to-back diagonal contact ball bearings is guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of bearing processing, and in particular to a testing device for a self-preloaded back-to-back diagonal contact ball bearing. Background Technology

[0002] Angular contact ball bearings are a special type of ball bearing that can simultaneously withstand radial and axial loads and operate at high speeds. Like conventional deep groove ball bearings, angular contact ball bearings consist of an inner ring, outer ring, rolling elements, and a cage. However, the raceway of angular contact ball bearings differs from that of conventional deep groove ball bearings, particularly the raceway flanges of the outer ring. Specifically, one side of the outer ring raceway has a high flange, and the other side has a low flange. During assembly, the rolling elements can pass over the low flange to enter the raceway, while the high flange serves as the load-bearing side.

[0003] Angular contact ball bearings are generally used in combination in practical applications, meaning two, three, or even more sets of angular contact ball bearings are assembled together in a specific configuration. The basic assembly methods are back-to-back assembly, face-to-face assembly, and tandem assembly. The specific assembly method is selected based on the actual working conditions. In a face-to-face assembly, the lower flanges of the outer raceways of the two angular contact ball bearings are arranged face-to-face. In a tandem assembly, the lower flanges of the outer raceways of the two angular contact ball bearings face the same direction, and the bearings are arranged sequentially along the axial direction. In a back-to-back assembly, the lower flanges of the outer raceways of the two angular contact ball bearings are arranged back-to-back.

[0004] Double-row angular contact ball bearings are a specific type of angular contact ball bearing. Specifically, they have two raceways on the inner ring and two corresponding raceways on the outer rings, each with one raceway. This design offers the advantage of minimal axial space requirement. Double-row angular contact ball bearings are also available in face-to-face assembly and tandem assembly configurations. For example, Chinese invention patent application CN 105114447 A discloses a face-to-face assembly double-row angular contact ball bearing and its assembly method, while Chinese invention patent CN 105041852 B discloses a tandem assembly angular contact ball bearing and its assembly method.

[0005] like Figure 1 The diagram shows a self-preloaded back-to-back diagonal contact ball bearing, including an inner ring 06, a first outer ring 01, a first cage 07, a second outer ring 03, a second cage 04, and rolling elements 05. A spacer 02 is provided between the first outer ring 01 and the second outer ring 03. Figure 2The diagram shows the structure of the first outer ring 01 or the second outer ring 03. One side of the groove 10 is a low side 08, and the other side is a high side 09. Compared with face-to-face assembly and tandem assembly, back-to-back assembly has the advantages of reliable assembly, simultaneous bearing of axial loads in two directions, and self-preload. However, back-to-back double-row angular contact ball bearings also have disadvantages such as difficult assembly, difficult preload control, and inconvenient preload adjustment, which limit the production efficiency and large-scale promotion of back-to-back angular contact ball bearings. Summary of the Invention

[0006] The technical problem to be solved by this utility model is to provide a testing device for a self-preloaded back-to-back diagonal contact ball bearing, which can measure the starting torque of the bearing and use the starting torque measurement to replace the preload measurement to determine the bearing processing quality, thereby ensuring the efficient and reliable production of back-to-back diagonal contact ball bearings.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a testing device for self-preloaded back-to-back diagonal contact ball bearings, comprising an outer ring mounting assembly, an inner ring clamping assembly, and a torque measuring assembly; the outer ring mounting assembly comprises a test mounting base and a test load block, the top surface of the test mounting base being the outer ring bearing surface, and the test load block having an outer ring loading surface; in the test state, the test load block is located above the test mounting base, forming an outer ring mounting area between the outer ring loading surface and the outer ring bearing surface;

[0008] The inner ring clamping assembly includes a clamping rod and two clamping end caps. The clamping end caps are connected to the clamping rod, and the two clamping end caps form an inner ring clamping area. The torque measuring assembly is detachably connected to the clamping rod.

[0009] During the measurement operation, the assembled bearing inner ring is placed between the two clamping end caps and locked. One end of the outer ring is placed on the outer ring bearing surface of the test mounting base, and the test load block is placed on the other end of the outer ring. The test load block and the test mounting base together press the outer ring together. The torque measuring component is connected to the clamping rod, driving the inner ring and the inner ring clamping component to rotate relative to the outer ring. The measured starting torque is obtained through the torque measuring component.

[0010] The testing device of this application can measure the starting torque of the bearing, and use the starting torque measurement to replace the preload measurement to determine the bearing processing quality, so as to ensure the efficient and reliable production of back-to-back angular contact ball bearings.

[0011] Preferably, the test load block is provided with a clearance hole, which is axially penetrating the test load block; in the test state, the upper end of the clamping rod passes through the clearance hole, and the torque measuring component is connected to the upper end of the clamping rod.

[0012] Preferably, one end of the clamping rod is integrally formed with one of the clamping end caps, and the other clamping end cap is detachably sleeved on the clamping rod; the inner ring clamping assembly also includes a locking ring, which is sleeved on the clamping rod and threadedly connected to the clamping rod.

[0013] Preferably, the torque measuring component includes a torque wrench.

[0014] Preferably, the inner ring clamping assembly is made of plastic to reduce the influence of the weight of the inner ring clamping assembly on the torque measurement results.

[0015] Preferably, the outer ring bearing surface is provided with a compensation operation hole; it also includes a self-weight compensation component, which includes a top plate and an adjustment mechanism. The top plate is disposed in the compensation operation hole, and the adjustment mechanism is connected to the test mounting base and is adjustable up and down. The top plate is connected to the adjustment mechanism, and a pressure sensor is provided between the top plate and the adjustment mechanism.

[0016] During the initial measurement, after the inner ring and inner ring clamping assembly are placed on the outer ring bearing surface, the position of the top plate is adjusted by the adjustment mechanism until the top plate contacts the inner ring clamping assembly. The top plate compensates for the self-weight of the inner ring and inner ring clamping assembly. The magnitude of the compensation force can be directly obtained through a pressure sensor, and the magnitude of the compensation force can be adjusted by the adjustment mechanism until the compensation force basically compensates for the self-weight of the inner ring and inner ring clamping assembly.

[0017] Preferably, the top plate and the adjustment mechanism are connected by a spring.

[0018] The top plate is set by a spring-loaded floating mechanism, which makes it more convenient and reliable to adjust the magnitude of the compensation force. Attached Figure Description

[0019] Figure 1 This is a cross-sectional view of a self-preloaded back-to-back diagonal contact ball bearing.

[0020] Figure 2 This is a cross-sectional view of the first or second outer ring in a self-preloaded back-to-back diagonal contact ball bearing.

[0021] Figure 3 This is a schematic diagram of the spacer ring selection device in the selection equipment for the self-preloaded back-to-back diagonal contact ball bearings in this embodiment;

[0022] Figure 4 This is a schematic diagram of the spacer selection device in the spacer selection operation state of the self-preloaded back-to-back diagonal contact ball bearing selection equipment in this embodiment;

[0023] Figure 5 for Figure 4A magnified view of a section at point A in the middle;

[0024] Figure 6 This is a schematic diagram of the structure of the first assembly component in the optional equipment for the self-preloaded back-to-back diagonal contact ball bearings in this embodiment;

[0025] Figure 7 This is a structural diagram of the first assembly component in the first outer ring assembly state of the self-preloaded back-to-back diagonal contact ball bearing selection equipment in this embodiment, where the rolling elements are not pressed into the first outer ring.

[0026] Figure 8 This is a structural diagram of the first assembly component in the first outer ring assembly state of the self-preloaded back-to-back diagonal contact ball bearing selection equipment in this embodiment, where the rolling elements have been pressed into the first outer ring.

[0027] Figure 9 This is a schematic diagram of the structure of the second assembly component in the optional equipment for the self-preloaded back-to-back diagonal contact ball bearings in this embodiment;

[0028] Figure 10 This is a structural diagram of the second assembly component in the optional equipment for the preloaded back-to-back diagonal contact ball bearings of this embodiment, showing the second outer ring being assembled. At this time, the cage positioning ring is installed.

[0029] Figure 11 This is a schematic diagram of the second assembly assembly in the second outer ring assembly state of the optional equipment for the self-preloaded back-to-back diagonal contact ball bearing in this embodiment. At this time, the rolling elements are installed but not pressed into the second outer ring.

[0030] Figure 12 This is a structural diagram of the second assembly component in the optional equipment for the preloaded back-to-back diagonal contact ball bearings of this embodiment, showing the second outer ring being assembled. At this point, the rolling elements have been pressed into the second outer ring.

[0031] Figure 13 This is a schematic diagram of the testing device in the optional equipment for the self-preloaded back-to-back diagonal contact ball bearings in this embodiment;

[0032] Figure 14 This is a schematic diagram of the inner ring clamping assembly in the optional equipment for the self-preloaded back-to-back diagonal contact ball bearings in this embodiment;

[0033] Figure 15 This is a schematic diagram of the structure of the outer ring mounting assembly and the self-weight compensation assembly in the optional equipment of the self-preloaded back-to-back diagonal contact ball bearing in this embodiment. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model. Example

[0035] like Figure 1 As shown, Figures 3-15 As shown, the equipment for selecting self-preloaded back-to-back angular contact ball bearings includes a spacer selection device, an assembly device, and a testing device, which are set up separately.

[0036] Specifically, such as Figures 3-5 As shown, the spacer ring fitting device includes a fitting mounting base 13, a fitting load block 11, and an end face measuring instrument 12. The top surface of the fitting mounting base 13 is an outer ring positioning surface 151, and an inner ring receiving hole 14 is formed on the outer ring positioning surface 151. The end face measuring instrument 12 is disposed in the inner ring receiving hole 14. The fitting load block 11 is provided with an inner ring loading surface 111. The loading end of the fitting load block 11 is provided with a limiting mandrel 112, and annularly distributed inner ring loading steps are provided on the outer side of the limiting mandrel 112. The inner ring loading surface 111 is disposed on the inner ring loading steps. The limiting mandrel 112 is used to insert the inner ring and plays a positioning role between the fitting load block 11 and the inner ring.

[0037] Specifically, such as Figures 3-5 As shown, the optional mounting base 13 includes a mounting base and a standard ring 15. The mounting base and the standard ring 15 are separately arranged vertically. The inner ring receiving hole 14 penetrates the standard ring 15 and extends into the mounting base. The end face measuring instrument 12 is disposed in the mounting base, and the detection end of the end face measuring instrument 12 is aligned with the upper end face of the mounting base. The length of the standard ring 15 corresponds to the length of the inner ring. Different specifications of standard rings 15 can be selected according to different inner ring lengths to improve the applicability.

[0038] During the spacer selection process, the first outer ring, first cage, and corresponding number of rolling elements are assembled onto the first end of the inner ring. The inner ring is inserted into the inner ring receiving hole 14, and the detection end of the end face measuring instrument 12 contacts the end face of the inner ring. The inner ring loading surface 111 of the optional load block 11 is pressed onto the first outer ring, and the reading of the end face measuring instrument 12 is recorded. The first outer ring and first cage are then disassembled, and the second outer ring, second cage, and corresponding number of rolling elements are assembled onto the second end of the inner ring. The inner ring is inserted into the inner ring receiving hole 14, and the detection end of the end face measuring instrument 12 contacts the end face of the inner ring. The lower end face of the second outer ring is placed on the outer ring positioning surface 151, and the inner ring loading surface 111 of the optional load block 11 is pressed onto the second outer ring, and the reading of the end face measuring instrument 12 is recorded. The height of the spacer can be determined based on the two readings of the end face measuring instrument 12, and the corresponding spacer can be selected.

[0039] Before assembly, the height requirement of the spacer can be determined by selecting the appropriate spacer, and then the corresponding spacer can be selected for assembly. This can effectively improve the preload setting accuracy of back-to-back diagonal contact ball bearings and simplify the preload adjustment operation.

[0040] like Figures 6-12 As shown, the assembly device includes a first assembly assembly and a second assembly assembly, such as... Figures 6-8 As shown, the first assembly component includes a first assembly mold 21. The top surface of the first assembly mold 21 is provided with a first assembly boss 22, and the first assembly boss 22 is provided with an inner ring mounting hole 23. Specifically, the height of the first assembly boss 22 is denoted as h, the outer diameter as D, the height of the inner ring mounting hole 23 is denoted as H, and the hole diameter as d. Thus, h = 0.3~0.4H, and d = 0.85~0.9D.

[0041] The first outer ring assembly step uses a first assembly assembly component. The inner ring is inserted into the inner ring mounting hole 23. The first outer ring is placed on the first assembly mold 21 and fitted over the first assembly boss 22. The first cage is placed on the first assembly boss 22. The rolling elements are sequentially inserted into the first cage. During the insertion of the rolling elements, the first outer ring restricts the outward movement of the rolling elements. The first outer ring is then lifted upwards, and the rolling elements are pressed into the grooves of the first outer ring, completing the assembly operation of the first outer ring.

[0042] like Figures 9-12As shown, the second assembly component includes a second assembly mold 24 and a retainer positioning ring 27. The top surface of the second assembly mold 24 is provided with a positioning mandrel 26, and the outer side of the positioning mandrel 26 is provided with an inner ring positioning step 25. The retainer positioning ring 27 is separately disposed from the second assembly mold 24, and the inner diameter of the retainer positioning ring 27 is larger than that of the positioning mandrel 26. Specifically, the outer diameter of the inner ring positioning step 25 is denoted as B, and the outer diameter of the positioning mandrel 26 is denoted as b, so b = 0.8~0.85B. The retainer positioning ring 27 is divided into at least two sub-rings circumferentially, and the central angle corresponding to each sub-ring is not greater than 180°. After assembly, the retainer positioning ring 27 can be easily and conveniently removed.

[0043] The second outer ring assembly step utilizes a second assembly assembly component. The intermediate component is rotated and mounted on the second assembly mold 24, with the inner ring fitted onto the positioning mandrel 26. The first end of the inner ring is positioned on the inner ring positioning step 25. The second outer ring is fitted over the inner ring, and the cage positioning ring 27 is placed on the first cage. The second cage is then placed on the cage positioning ring 27. The rolling elements are sequentially inserted into the second cage. The second outer ring is lifted upwards, and the rolling elements are pressed into the grooves of the second outer ring, completing the assembly of the second outer ring. Finally, the spacer ring is pressed between the first and second outer rings, completing the bearing assembly.

[0044] like Figures 13-15 As shown, the testing device includes an outer ring mounting assembly, an inner ring clamping assembly 34, and a torque measuring assembly 35. The outer ring mounting assembly includes a test mounting base 32 and a test load block 31. The top surface of the test mounting base 32 is the outer ring bearing surface 321, and the test load block 31 has an outer ring loading surface 311. Specifically, the test load block 31 has a clearance hole 312, which axially penetrates the test load block 31. In the test state, the test load block 31 is located above the test mounting base 32, forming an outer ring mounting area between the outer ring loading surface 311 and the outer ring bearing surface 321. The upper end of the clamping rod 341 passes through the clearance hole 312, and the torque measuring assembly 35 is connected to the upper end of the clamping rod 341.

[0045] like Figure 13 and Figure 14As shown, the inner ring clamping assembly 34 includes a clamping rod 341 and two clamping end caps 342. The clamping end caps 342 are connected to the clamping rod 341, and an inner ring clamping area is formed between the two clamping end caps 342. One end of the clamping rod 341 is integrally formed with one of the clamping end caps 342, and the other clamping end cap 342 is detachably sleeved on the clamping rod 341. The inner ring clamping assembly 34 also includes a locking ring 343, which is sleeved on the clamping rod 341 and threadedly connected to the clamping rod 341. The torque measuring assembly 35 includes a torque wrench, and the torque measuring assembly 35 is detachably connected to the clamping rod 341.

[0046] To reduce the impact of the weight of the inner ring and the inner ring clamping assembly 34 on the torque measurement results, the inner ring clamping assembly 34 is made of low-density plastic.

[0047] The measurement process uses an inner ring clamping assembly 34 to place and lock the inner ring between two clamping end caps 342. One end of the outer ring is placed on the outer ring bearing surface 321 of the test mounting base 32, and the test load block 31 is placed on the other end of the outer ring. The test load block 31 and the test mounting base 32 together press the outer ring together. The torque measuring assembly 35 is connected to the clamping rod 341, driving the inner ring and the inner ring clamping assembly 34 to rotate relative to the outer ring. The measured starting torque is obtained through the torque measuring assembly 35.

[0048] like Figure 13 and Figure 15 As shown, the outer ring bearing surface 321 is further provided with a compensation operation hole 322. The testing device also includes a self-weight compensation component 33, which includes a top plate 331 and an adjustment mechanism 332. The top plate 331 is disposed within the compensation operation hole 322, and the adjustment mechanism 332 is connected to the test mounting base 32 and is adjustable vertically. The top plate 331 is connected to the adjustment mechanism 332, and a pressure sensor is provided between the top plate 331 and the adjustment mechanism 332. Specifically, the top plate 331 and the adjustment mechanism 332 are connected by a spring 333.

[0049] During the starting torque measurement, after the inner ring and inner ring clamping assembly 34 are placed on the outer ring bearing surface 321, the position of the top plate 331 is adjusted by the adjusting mechanism 332 until the top plate 331 contacts the inner ring clamping assembly 34, and the top plate 331 compensates for the self-weight of the inner ring and inner ring clamping assembly 34. The magnitude of the compensation force can be directly obtained through a pressure sensor, and the magnitude of the compensation force can be adjusted by the adjusting mechanism 332 until the compensation force basically compensates for the self-weight of the inner ring and inner ring clamping assembly 34. The top plate 331 is floating by a spring 333, which makes the adjustment of the compensation force more convenient and the adjustment accuracy more reliable.

[0050] The optional equipment in this application can ingeniously complete the assembly of back-to-back angular contact ball bearings, achieving efficient and reliable assembly operations. It can also measure the starting torque of the bearing, using the starting torque measurement instead of the preload measurement to determine the bearing processing quality, thus ensuring the efficient and reliable production of back-to-back angular contact ball bearings.

[0051] The selection method for self-preloaded back-to-back angular contact ball bearings employs the selection equipment described above and includes at least the following steps:

[0052] S01. Spacer height measurement: Select inner ring 06, first outer ring 01, first cage 07, second outer ring 03, second cage 04 and a specific number of rolling elements 05.

[0053] Using a spacer ring fitting device, the first outer ring, the first cage, and the corresponding number of rolling elements are assembled on the first end of the inner ring. The inner ring is inserted into the inner ring receiving hole 14 with its second end facing downwards. The detection end of the end face measuring instrument 12 is in contact with the end face of the second end of the inner ring. The lower end face of the first outer ring is placed on the outer ring positioning surface 151. The inner ring loading surface 111 of the optional load block 11 is pressed against the upper end face of the first outer ring, and the reading of the end face measuring instrument 12 is recorded. Figure 4 The state shown.

[0054] Disassemble the first outer ring and the first cage. Assemble the second outer ring, the second cage, and the corresponding number of rolling elements onto the second end of the inner ring. Insert the inner ring with its first end facing downwards into the inner ring receiving hole 14. The detection end of the end face measuring instrument 12 contacts the end face of the first end of the inner ring. Place the lower end face of the second outer ring on the outer ring positioning surface 151. Press the inner ring loading surface 111 of the optional load block 11 onto the upper end face of the second outer ring and record the reading of the end face measuring instrument 12. Determine the height of the spacer ring based on the two readings of the end face measuring instrument 12 and select the corresponding spacer ring 02.

[0055] S02. Spacer Grouping: The height of the spacers is measured, and a certain number of spacers are divided into several groups with a height accuracy of 2µm. After measurement, the spacers are cut into two half-rings along the diameter line. This measurement and grouping operation facilitates the selection and replacement of spacers, improving selection efficiency. The half-rings can be easily pressed into the spacers from both sides between the first and second outer rings.

[0056] S1. First Outer Ring Assembly: Using the first assembly assembly, the inner ring is installed into the inner ring mounting hole 23 with the first end facing upwards and the second end facing downwards. At this time, the first groove on the inner ring is set higher than the first assembly boss 22, and the second groove on the inner ring is located within the inner ring mounting hole 23. The first outer ring is placed on the top surface of the first assembly mold 21 and fitted over the first assembly boss 22. At this time, the lower edge of the groove on the first outer ring is set upwards. The first cage is placed on the first assembly boss 22, and the ball pocket hole of the first cage is aligned with the first groove of the inner ring. A specific number of rolling elements are sequentially installed into the first cage. During the installation of the rolling elements, the first outer ring restricts the outward movement of the rolling elements, i.e., as shown in the image. Figure 7 The state shown is as follows. The first outer ring is lifted upwards, and the rolling elements are pressed into the grooves of the first outer ring. At this point, the inner ring, the first outer ring, the first cage, and the rolling elements together form the intermediate component, as shown. Figure 8 The state shown.

[0057] S2. Second Outer Ring Assembly: Using the second assembly assembly, the intermediate part is installed on the second assembly mold 24, wherein the inner ring is sleeved on the positioning mandrel 26 with the second end facing upwards, and the first end of the inner ring is set on the inner ring positioning step 25, i.e. Figure 10 As shown in the diagram. The second outer ring is fitted over the inner ring and abuts against the first outer ring, with the lower edge of the groove on the second outer ring facing upwards. The cage locating ring 27 is placed on the first cage, and then the second cage is placed on the cage locating ring 27, with the ball pocket hole of the second cage aligned with the second groove of the inner ring. A specific number of rolling elements are sequentially inserted into the second cage. The second outer ring is then lifted upwards, and the rolling elements are pressed into the groove of the second outer ring, i.e. Figure 11 The state shown.

[0058] S3. Spacer assembly: Press the spacer between the first and second outer rings to complete the bearing assembly, i.e., as shown below. Figure 12 The state shown.

[0059] S4. Starting torque test: Using the inner ring clamping assembly 34, place the inner ring between the two clamping end caps 342 and lock them in place. Figure 14 As shown in the diagram, one end of the outer ring is placed on the outer ring bearing surface 321 of the test mounting base 32, and the test load block 31 is placed on the other end of the outer ring. The loading surface 311 of the outer ring contacts the corresponding end face of the outer ring, and the test load block 31 and the test mounting base 32 together press the outer ring together, i.e., as shown in the diagram. Figure 13The state is shown. Connect the torque measuring component 35 to the clamping rod 341, drive the inner ring and the inner ring clamping component 34 to rotate relative to the outer ring, and obtain the measured starting torque through the torque measuring component 35. Compare the measured starting torque with the designed starting torque. If the measured starting torque is not greater than the designed starting torque, it is determined to meet the design requirements and the product is qualified. When the measured starting torque is greater than the designed starting torque, it is determined to not meet the design requirements. Remove the current spacer ring, select a spacer ring in the adjacent group of the current spacer ring, and repeat steps S3 and S4.

[0060] In summary, the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A testing device for a pre-tensioned back-to-back duplex angular contact ball bearing, characterized in that: The outer ring mounting assembly, the inner ring clamping assembly and the torque measurement assembly; the outer ring mounting assembly comprises a test mounting seat and a test load block, the top surface of the test mounting seat is an outer ring bearing surface, and the test load block is provided with an outer ring loading surface; in the test state, the test load block is located above the test mounting seat, and an outer ring mounting interval is formed between the outer ring loading surface and the outer ring bearing surface; The inner ring clamping assembly comprises a clamping rod and two clamping end covers, the clamping end covers are connected with the clamping rod, and an inner ring clamping interval is formed between the two clamping end covers; the torque measurement assembly is detachably connected with the clamping rod.

2. The test device of claim 1, wherein: The test load block is provided with an avoiding hole, the avoiding hole is arranged through the test load block in the axial direction; in the test state, the upper end of the clamping rod is arranged through the avoiding hole, and the torque measurement assembly is connected with the upper end of the clamping rod.

3. The test device of claim 2, wherein: One end of the clamping rod is integrally arranged with one of the clamping end covers, and the other clamping end cover is detachably sleeved on the clamping rod; the inner ring clamping assembly further comprises a locking ring, the locking ring is sleeved on the clamping rod and is threadedly connected with the clamping rod.

4. The test device of claim 1, wherein: The torque measurement assembly comprises a torque wrench.

5. The test device of claim 1, wherein: The inner ring clamping assembly is made of plastic.

6. The test device of any one of claims 1-4, wherein: The outer ring bearing surface is provided with a compensation operation hole; further comprising a self-weight compensation assembly, the self-weight compensation assembly comprises a top plate and an adjusting mechanism, the top plate is arranged in the compensation operation hole, the adjusting mechanism is connected with the test mounting seat and is adjusted up and down, the top plate is connected with the adjusting mechanism, and a pressure sensor is arranged between the top plate and the adjusting mechanism.

7. The test device of claim 6, wherein: The top plate and the adjusting mechanism are connected through a spring.

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