Spring fatigue test equipment

Abstract

The invention discloses spring fatigue test equipment, and relates to the technical field of spring test equipment. The device comprises a rack and a first semicircular plate, a first support is installed on the rack, a sliding rail is connected to the rack, a second support is arranged on the sliding rail in a sliding mode, and a round bar is movably inserted into the second support. A sliding plate can be pushed to slide along the inner surface of a sliding rail through a connecting rod, a second support can be pushed to move back and forth along the sliding rail through a pressure sensor, in the process, a detected spring can be repeatedly stretched and compressed, and the fatigue performance of the spring is tested; the position of the sliding plate can be adjusted, and the closer the sleeve block is to the position of the turntable, so that the pressure when the spring is compressed can be adjusted, and the pressure when the spring is detected can be adjusted while the fatigue of the spring can be tested.

Description

Technical Field

[0001] The present invention relates to the technical field of spring testing equipment, in particular to spring fatigue testing equipment. Background Art

[0002] A spring is a mechanical component that utilizes elasticity to function. Parts made of elastic materials deform under external forces and return to their original shape when the force is removed. Generally made of spring steel, springs come in a variety of shapes and sizes. All springs subject to variable loads must undergo fatigue testing during internal quality control, customer inspections, new product finalization and certification, industry spot checks, and process adjustments.

[0003] Existing spring fatigue testing equipment adjusts the pressure of the spring during the test process during the fatigue test of the spring, which is difficult to meet different testing requirements and cannot comprehensively and accurately evaluate the fatigue performance of the spring under different pressure conditions. In addition, when only a single spring model can be tested, it is not convenient to replace different molds with different springs for testing according to actual conditions. In response to the above problems, the inventors proposed a spring fatigue testing equipment to solve the above problems. Summary of the Invention

[0004] In order to solve the problem of adjusting the pressure of the spring during the fatigue test and testing springs of different sizes during the test, the purpose of the present invention is to provide a spring fatigue testing device.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: a spring fatigue testing device comprises a stand and a first semicircular plate, the stand is equipped with a first bracket, the stand is connected to a slide rail, a second bracket is slidably provided on the slide rail, a round rod is movably inserted into the second bracket, the round rod movably passes through the first bracket and the second bracket, the round rod is installed on the first bracket, a pressure sensor is fixedly provided on one side of the second bracket, the pressure sensor is arranged in the slide rail, the first semicircular plate is assembled with the second semicircular plate, and a pressure regulating reciprocating test assembly is fixedly provided on the upper surface of the stand, which is used to test the fatigue of the spring and adjust the pressure of the spring when it is tested;

[0006] The cam is fixedly mounted on the support frame, and the cam is fixedly provided with a first vertical plate, and a support shell is fixedly provided on one side of the cam frame. A driving motor is fixedly provided in the supporting shell, and an output end of the driving motor passes through the fixed seat. A combined cam is provided on the output end of the driving motor. A first round rod slides in the combined cam, and a first rotating rod is rotatably provided at one end of the first round rod. A through slot is provided on one side of the first rotating rod, and a connecting rod is rotatably provided at the other end of the first rotating rod. A slide is slidably provided in the slide rail, and a fixed block is fixed on the upper surface of the slide. The other end of the connecting rod is rotatably connected between the fixed blocks, and one side of the slide is connected to the pressure The force sensor is connected, the fixed seat is provided with a groove, the screw rod is rotated in the groove, the outer surface of the screw rod is threadedly sleeved with a sleeve block, the sleeve block is slidably fitted with the inner surface of the groove, a connecting block is fixedly provided on the upper surface of the sleeve block, one side of the connecting block is fixedly provided with a second round rod, the second round rod passes through the through-groove, the second round rod slides and fits with the inner surface of the through-groove, one end of the screw rod is fixedly provided with a round block, the round block passes through the fixed seat, the outer surface of the round block is fixedly sleeved with a turntable, a transverse groove is provided on one side of the fixed seat, and a second rotating rod is rotatably provided on the side of the first rotating rod away from the combined cam. A second vertical plate is provided on the fixed seat, and the other end of the second rotating rod is rotatably connected to the second vertical plate;

[0007] The first semicircular plate, the first bracket and the second bracket are provided with quick-release assemblies for replacing and adapting springs of the same size.

[0008] Preferably, a protrusion is fixedly provided on the outer surface of the round rod, and a mounting bolt is threadedly inserted into the side surface of the protrusion, and the end portion of the mounting bolt is threadedly inserted in the first bracket, and the outer surfaces of the first semicircular plate and the second semicircular plate are both fixedly provided with a U-shaped block, and a through hole is opened in the U-shaped block, and a first bolt is movably inserted in the through hole, and a nut is threadedly sleeved on the outer surface of the first bolt, and a plurality of heat dissipation holes are opened on the lower surface of the support shell, and a plurality of heat dissipation hole arrays are distributed on the lower surface of the support shell, and a semicircular notch is opened on the outer surface of the turntable, and a semicircular notch ring array is distributed on the outer surface of the turntable, and the transverse groove is connected to the groove, and a positioning block is fixedly provided on one side of the sleeve block, and the positioning block slides in fit with the inner surface of the transverse groove, and a scale is provided on one side of the fixing seat, and holes for matching the round rod are opened on the first bracket and the second bracket.

[0009] Preferably, the quick-disconnect assembly includes a first spring, a cylinder is fixedly provided on the upper surfaces of the first bracket and the second bracket, the first spring is fixedly connected to the inner surface of the cylinder, a circular plate is fixedly provided at the lower end of the first spring, a movable rod is fixedly provided on the upper surface of the circular plate, the movable rod movably passes through the cylinder, a limit plate is fixedly provided on the lower surface of the circular plate, a socket is provided on the side surfaces of the first bracket and the second bracket, an inserting plate is fixedly provided on one side of the first semicircular plate, the inserting plate is movably inserted in the socket, a limiting opening is provided in the inserting plate, and the limit plate is movably inserted in the limiting opening.

[0010] Preferably, four first springs are provided, and an annular array of the first springs is distributed between the inner surface of the cylinder and the circular plate, and the cross-section of the movable rod is "T"-shaped.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] 1. The present invention starts a drive motor, which drives the combined cam to rotate. The connecting rod pushes the slide plate to slide along the inner surface of the slide rail. The pressure sensor pushes the second bracket to move back and forth along the slide rail. During this process, the spring under test can be repeatedly stretched and compressed to test the fatigue performance of the spring. The position of the slide plate can be adjusted by rotating the turntable so that it passes through the round block, thereby rotating the lead screw. The closer the sleeve block is to the turntable, the more the pressure when compressing the spring can be adjusted. This allows the fatigue of the spring to be tested and the pressure of the spring to be adjusted at the same time.

[0013] 2. The present invention places the first semicircular plate and the second semicircular plate on the side surfaces of the round rod respectively. After the first semicircular plate and the second semicircular plate are fitted together, the first bolt is movably inserted into the through hole and assembled with the nut. The movable rod can be pulled to disengage the limit plate from the socket. When the movable rod is loosened, the limit plate can be inserted into the limit opening by the force of the first spring. The end of the spring to be tested enters the first semicircular plate and the second semicircular plate and can be limited. The first semicircular plate and the second semicircular plate of different sizes can be installed according to the diameter of the test spring, thereby improving the practicality of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0015] Figure 1 It is a structural schematic diagram of the present invention.

[0016] Figure 2 This is a schematic structural diagram of the pressure regulating reciprocating test assembly of the present invention.

[0017] Figure 3 For the present invention Figure 2 Enlarged structural diagram at point A in the middle.

[0018] Figure 4 It is a schematic diagram of the combined cam structure of the present invention.

[0019] Figure 5 This is a schematic diagram of the structure of the first semicircular plate of the present invention.

[0020] Figure 6 This is a schematic diagram of the first bracket structure of the present invention.

[0021] Figure 7 For the present invention Figure 6 Enlarged structural diagram at point B in the middle.

[0022] Figure 8 For the present invention Figure 6 Enlarged structural diagram at point C in the middle.

[0023] In the figure: 1. Test stand; 11. First bracket; 12. Slide rail; 13. Second bracket; 14. Pressure sensor; 15. Round rod; 16. Bump; 17. Mounting bolt; 2. First semicircular plate; 21. Second semicircular plate; 22. U-shaped block; 23. Through hole; 24. First bolt; 25. Nut; 3. Pressure regulating reciprocating test assembly; 31. Fixing seat; 32. First vertical plate; 33. Support shell; 331. Heat dissipation hole; 34. Drive motor; 35. Combined cam; 37. First round rod; 38. First rotating rod; 381. Connecting rod; 382. Slide plate; 383. Fixed block; 39. Through slot; 4. Groove; 41. Screw rod; 42. Bushing block; 43. Connecting block; 44. Second round rod; 45. Round block; 46. Turntable; 461. Semicircular notch; 47. Horizontal groove; 48. Positioning block; 49. Scale; 5. Second rotating rod; 51. Second vertical plate; 6. Quick-release assembly; 61. Cylinder; 62. First spring; 63. Round plate; 64. Movable rod; 65. Socket; 66. Limit plate; 67. Insert plate; 68. Limit opening. DETAILED DESCRIPTION

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0025] Example 1: Figure 1-8As shown, the present invention provides a spring fatigue testing device, including a stand 1 and a first semicircular plate 2, a first bracket 11 is installed on the stand 1, a display device is provided on the stand 1, and the data during the test can be displayed, a slide rail 12 is connected to the stand 1, a second bracket 13 is slidably provided on the slide rail 12, a round rod 15 is movably inserted into the second bracket 13, the round rod 15 movably passes through the first bracket 11 and the second bracket 13, the first bracket 11 and the second bracket 13 are provided with holes for matching the round rod 15, the round rod 15 is installed on the first bracket 11, and the second bracket 13 is provided with a hole for matching the round rod 15. A pressure sensor 14 is fixedly provided on one side. The spring to be tested can be placed between the first bracket 11 and the second bracket 13, and then the round rod 15 can be inserted into the hole of the matching round rod 15 opened on the first bracket 11. The round rod 15 passes through the spring, and then the round rod 15 can be connected to the first bracket 11 by installing bolts 17. The pressure sensor 14 is set in the slide rail 12. The second semicircular plate 21 is assembled on the first semicircular plate 2. The upper surface of the bench 1 is fixed with a pressure adjustment reciprocating test assembly 3, which is used to test the fatigue of the spring and adjust the pressure of the spring when it is tested;

[0026] The pressure regulating reciprocating test assembly 3 includes a fixed seat 31, which is fixedly connected to the upper surface of the test stand 1, and a first vertical plate 32 is fixed on the fixed seat 31, and a support shell 33 is fixed on one side of the first vertical plate 32, and a lower surface of the support shell 33 is provided with a plurality of heat dissipation holes 331, and a plurality of the heat dissipation holes 331 are arrayed on the lower surface of the support shell 33 to assist the drive motor 34 in dissipating heat. A drive motor 34 is fixed in the support shell 33, and the speed of the compression spring can be controlled by controlling the speed of the output end of the drive motor 34. The output end of the drive motor 34 passes through the fixed seat 31, and the output end of the drive motor 34 is provided with a combined cam 35, and a first round rod 37 slides in the combined cam 35, and a first rotating rod 38 is rotatably provided at one end of the first round rod 37, and a through slot 39 is provided on one side of the first rotating rod 38, and a connecting rod 381 is rotatably provided at the other end of the first rotating rod 38, and a slide plate 382 is slidably provided in the slide rail 12, and the upper surface of the slide plate 382 is fixed A fixing block 383 is provided, and the other end of the connecting rod 381 is rotatably connected between the fixing blocks 383. One side of the slide 382 is connected to the pressure sensor 14. A groove 4 is provided on the fixing seat 31. A screw rod 41 is rotated in the groove 4. A sleeve 42 is provided on the outer surface of the screw rod 41. The sleeve 42 slides and fits with the inner surface of the groove 4. A connecting block 43 is fixed on the upper surface of the sleeve 42. A second round rod 44 is fixed on one side of the connecting block 43. The second round rod 44 is fixed on one side of the connecting block 43. The rod 44 passes through the through-slot 39, and the second round rod 44 slides in contact with the inner surface of the through-slot 39. A round block 45 is fixed to one end of the screw rod 41. The round block 45 passes through the fixing seat 31. A rotating disk 46 is fixedly sleeved on the outer surface of the round block 45. A transverse groove 47 is formed on one side of the fixing seat 31. A second rotating rod 5 is rotatably provided on the side of the first rotating rod 38 away from the combined cam 35. A second vertical plate 51 is provided on the fixing seat 31. The other end of the second rotating rod 5 is rotatably connected to the second vertical plate 51.

[0027] The first semicircular plate 2 and the first bracket 11 and the second bracket 13 are provided with a quick-release assembly 6 for replacing and adapting springs of the same size;

[0028] A protrusion 16 is fixedly provided on the outer surface of the round rod 15, and a mounting bolt 17 is threadedly inserted into the side surface of the protrusion 16. The end of the mounting bolt 17 is threadedly inserted into the first bracket 11. The mounting bolt 17 facilitates the installation of the round rod 15 and facilitates the replacement of the spring to be tested.

[0029] A U-shaped block 22 is fixedly provided on the outer surface of each of the first semicircular plate 2 and the second semicircular plate 21. A through hole 23 is provided in the U-shaped block 22. A first bolt 24 is movably inserted into the through hole 23. A nut 25 is threadedly sleeved on the outer surface of the first bolt 24 to facilitate assembly of the first semicircular plate 2 and the second semicircular plate 21. A semicircular notch 461 is provided on the outer surface of the turntable 46, and the semicircular notches 461 are distributed in a circular array on the outer surface of the turntable 46 to facilitate rotation of the turntable 46.

[0030] The transverse groove 47 is connected to the groove 4. A positioning block 48 is fixed on one side of the sleeve block 42. The positioning block 48 slides and fits with the inner surface of the transverse groove 47. A scale 49 is provided on one side of the fixing seat 31 to assist in positioning when adjusting the pressure. Holes for matching the round rod 15 are provided on the first bracket 11 and the second bracket 13 to facilitate the installation of the round rod 15.

[0031] The quick-disassembly assembly 6 includes a first spring 62, a cylinder 61 is fixedly provided on the upper surface of the first bracket 11 and the second bracket 13, the first spring 62 is fixedly connected to the inner surface of the cylinder 61, a circular plate 63 is fixedly provided at the lower end of the first spring 62, a movable rod 64 is fixedly provided on the upper surface of the circular plate 63, the movable rod 64 movably passes through the cylinder 61, a limiting plate 66 is fixedly provided on the lower surface of the circular plate 63, a socket 65 is provided on the side of the first bracket 11 and the second bracket 13, a plug-in plate 67 is fixedly provided on one side of the first semicircular plate 2, the plug-in plate 67 is movably inserted in the socket 65, a limiting opening 68 is provided in the plug-in plate 67, and the limiting plate 66 is movably inserted in the limiting opening 68, so as to connect the first semicircular plate 2 and the second semicircular plate 21 They are placed on the side surfaces of the round rod 15 respectively. After the first semicircular plate 2 and the second semicircular plate 21 are fitted together, the first bolt 24 is movably inserted into the through hole 23 and assembled with the nut 25. The movable rod 64 can be pulled to disengage the limiting plate 66 from the socket 65, and the inserting plate 67 can be inserted into the socket 65. The movable rod 64 is released and the limiting plate 66 can be inserted into the limiting opening 68 by the force of the first spring 62. Thus, the first semicircular plate 2 and the second semicircular plate 21 can be connected to the first bracket 11 and the second bracket 13. The end of the spring to be tested enters the first semicircular plate 2 and the second semicircular plate 21 and can be limited. According to the diameter of the test spring, first semicircular plates 2 and second semicircular plates 21 of different sizes can be installed to improve the practicality of the equipment.

[0032] There are four first springs 62 , and the first springs 62 are distributed in a circular array between the inner surface of the cylinder 61 and the circular plate 63 to improve the stability after the connection. The cross-sectional shape of the movable rod 64 is “T”-shaped, which facilitates pulling the movable rod 64 to move.

[0033] Working principle: When using the present invention, the spring to be tested can be placed between the first bracket 11 and the second bracket 13. Then, the round rod 15 can be inserted into the hole of the first bracket 11 to fit the round rod 15. The round rod 15 passes through the spring. Then, the round rod 15 can be connected to the first bracket 11 by installing the bolt 17.

[0034] The first semicircular plate 2 and the second semicircular plate 21 are placed on the side surfaces of the round rod 15 respectively. After the first semicircular plate 2 and the second semicircular plate 21 are fitted together, the first bolt 24 is movably inserted into the through hole 23 and assembled with the nut 25. The movable rod 64 can be pulled to disengage the limit plate 66 from the socket 65, and the inserting plate 67 can be inserted into the socket 65. The movable rod 64 is released and the force of the first spring 62 can be used to insert the limit plate 66 into the limit opening 68, so that the first semicircular plate 2 and the second semicircular plate 21 can be connected to the first bracket 11 and the second bracket 13. The end of the spring to be tested enters the first semicircular plate 2 and the second semicircular plate 21, which can be limited. According to the diameter size of the test spring, first semicircular plates 2 and second semicircular plates 21 of different sizes can be installed to improve the practicality of the equipment.

[0035] By starting the drive motor 34, the drive motor 34 drives the combined cam 35 to rotate, and the first rotating rod 38 slides and fits along the inner surface of the combined cam 35. The second round rod 44 and the through groove 39 cooperate to make the other end of the first rotating rod 38 swing. The connecting rod 381 can push the slide plate 382 to slide along the inner surface of the slide rail 12. The pressure sensor 14 can push the second bracket 13 to reciprocate along the slide rail 12. In this process, the tested spring can be repeatedly stretched and compressed to perform a fatigue performance test on the spring.

[0036] The screw rod 41 can also be rotated by rotating the turntable 46 through the round block 45, so that the sleeve block 42 arranged on its outer surface can slide along the inner surface of the groove 4, and the position of the second round rod 44 in the groove 39 can be adjusted. The position of the slide plate 382 can be adjusted. The closer the sleeve block 42 is to the turntable 46, the smaller the pressure of the compression spring. The pressure when the positioning block 48 is aligned can be observed, so that the pressure when the spring is compressed can be adjusted. While testing the fatigue of the spring, the pressure of the spring when it is tested can also be adjusted.

[0037] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A spring fatigue testing device, comprising a stand (1) and a first semicircular plate (2), characterized in that: A first bracket (11) is installed on the platform (1), a slide rail (12) is connected to the platform (1), a second bracket (13) is slidably provided on the slide rail (12), a round rod (15) is movably inserted on the second bracket (13), the round rod (15) movably passes through the first bracket (11) and the second bracket (13), the round rod (15) is installed on the first bracket (11), a pressure sensor (14) is fixedly provided on one side of the second bracket (13), the pressure sensor (14) is arranged in the slide rail (12), a second semicircular plate (21) is assembled on the first semicircular plate (2), and a pressure regulating reciprocating test assembly (3) is fixedly provided on the upper surface of the platform (1), which is used for testing the fatigue of the spring and adjusting the pressure of the spring when it is tested; The pressure regulating reciprocating test assembly (3) comprises a fixed seat (31), the fixed seat (31) is fixedly connected to the upper surface of the bench (1), a first vertical plate (32) is fixedly provided on the fixed seat (31), a support shell (33) is fixedly provided on one side of the first vertical plate (32), a driving motor (34) is fixedly provided in the support shell (33), an output end of the driving motor (34) passes through the fixed seat (31), a combined cam (35) is provided at the output end of the driving motor (34), and the combined cam (35) A first round rod (37) is slidably mounted on one end of the first round rod (37), a first rotating rod (38) is rotatably mounted on one side of the first rotating rod (38), a through slot (39) is provided on one side of the first rotating rod (38), a connecting rod (381) is rotatably mounted on the other end of the first rotating rod (38), a slide plate (382) is slidably mounted on the slide rail (12), a fixed block (383) is fixed on the upper surface of the slide plate (382), the other end of the connecting rod (381) is rotatably mounted between the fixed blocks (383), and one side of the slide plate (382) is in contact with the pressure plate. The sensor (14) is connected, the fixing seat (31) is provided with a groove (4), the screw rod (41) is rotated in the groove (4), the outer surface of the screw rod (41) is threadedly sleeved with a sleeve block (42), the sleeve block (42) is slidably fitted with the inner surface of the groove (4), the upper surface of the sleeve block (42) is fixed with a connecting block (43), one side of the connecting block (43) is fixed with a second round rod (44), the second round rod (44) passes through the through groove (39), and the second round rod (44) and the through groove (39) are fixedly connected. ) is slidably fitted on the inner surface of the screw rod (41), a round block (45) is fixedly provided on one end of the screw rod (41), the round block (45) passes through the fixed seat (31), a rotating disk (46) is fixedly sleeved on the outer surface of the round block (45), a transverse groove (47) is provided on one side of the fixed seat (31), a second rotating rod (5) is rotatably provided on the side of the first rotating rod (38) away from the combined cam (35), a second vertical plate (51) is provided on the fixed seat (31), and the other end of the second rotating rod (5) is rotatably connected to the second vertical plate (51); The first semicircular plate (2), the first bracket (11) and the second bracket (13) are provided with a quick-disassembly assembly (6) for replacing and adapting a spring of the same size.

2. The spring fatigue testing device according to claim 1, characterized in that: A protrusion (16) is fixedly provided on the outer surface of the round rod (15), a mounting bolt (17) is threadedly inserted into the side surface of the protrusion (16), and the end of the mounting bolt (17) is threadedly inserted into the first bracket (11).

3. The spring fatigue testing device according to claim 1, wherein: A U-shaped block (22) is fixedly provided on the outer surfaces of the first semicircular plate (2) and the second semicircular plate (21), a through hole (23) is provided in the U-shaped block (22), a first bolt (24) is movably inserted in the through hole (23), and a nut (25) is threadedly sleeved on the outer surface of the first bolt (24).

4. The spring fatigue testing device according to claim 1, wherein: The lower surface of the support shell (33) is provided with a plurality of heat dissipation holes (331), and the plurality of heat dissipation holes (331) are distributed in an array on the lower surface of the support shell (33).

5. The spring fatigue testing device according to claim 1, wherein: The outer surface of the turntable (46) is provided with semicircular notches (461), and the semicircular notches (461) are distributed in a circular array on the outer surface of the turntable (46).

6. The spring fatigue testing device according to claim 1, wherein: The transverse groove (47) is connected to the groove (4); a positioning block (48) is fixedly provided on one side of the sleeve block (42); the positioning block (48) is slidably fitted with the inner surface of the transverse groove (47); and a scale (49) is provided on one side of the fixing seat (31).

7. The spring fatigue testing device according to claim 1, wherein: The first bracket (11) and the second bracket (13) are provided with holes for matching with the round rod (15).

8. The spring fatigue testing device according to claim 1, wherein: The quick-disassembly assembly (6) includes a first spring (62), a cylinder (61) is fixedly provided on the upper surface of the first bracket (11) and the second bracket (13), the first spring (62) is fixedly connected to the inner surface of the cylinder (61), a circular plate (63) is fixedly provided at the lower end of the first spring (62), a movable rod (64) is fixedly provided on the upper surface of the circular plate (63), the movable rod (64) movably passes through the cylinder (61), a limiting plate (66) is fixedly provided on the lower surface of the circular plate (63), a socket (65) is provided on the side surface of the first bracket (11) and the second bracket (13), an inserting plate (67) is fixedly provided on one side of the first semicircular plate (2), the inserting plate (67) is movably inserted in the socket (65), a limiting opening (68) is provided in the inserting plate (67), and the limiting plate (66) is movably inserted in the limiting opening (68).

9. The spring fatigue testing device according to claim 8, wherein: Four first springs (62) are provided, and the first springs (62) are distributed in an annular array between the inner surface of the cylinder (61) and the circular plate (63).

10. The spring fatigue testing device according to claim 8, wherein: The cross-section of the movable rod (64) is T-shaped.

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