Multifunctional spring fatigue testing machine

Abstract

The invention relates to the field of reset element testing, in particular to a multifunctional spring fatigue testing machine which comprises a testing frame, a flat spring installation device and a testing device, the flat spring installation device and the testing device are installed on the testing frame, the flat spring installation device comprises an installation box body, and a plurality of testing cavities used for containing flat springs are arranged in the installation box body. The top of the mounting box body is provided with a cover plate used for sealing each test chamber, the flat spring mounting device further comprises a space adjusting mechanism used for adjusting the space size of the test chambers, and the space adjusting mechanism comprises a width adjusting unit and a thickness adjusting unit; the testing device comprises testing shafts which are connected in the testing cavities in a reciprocating sliding mode and a driving mechanism which is used for controlling the testing shafts to slide. The driving mechanism is provided with a stroke adjusting mechanism which is used for adjusting the stroke of the testing shafts. By implementing the scheme, the problem that equipment debugging is time-consuming and tedious before a flat spring test is solved.

Description

Technical Field

[0001] The present invention relates to the field of testing reset components, and particularly to a multi-functional spring fatigue testing machine. Background Art

[0002] A spring is an important component for resetting and buffering, and is widely used in various fields such as automobile manufacturing, aerospace engineering, electronic equipment, medical devices, etc. Since the fatigue performance of a spring is directly related to the overall life and operating stability of the equipment, it is particularly crucial to conduct accurate fatigue tests on the spring. Currently, for ordinary springs such as helical springs, the spring is usually sleeved on a test shaft for fatigue testing. In this way, regardless of how the size and specifications of the spring change, there is no need to perform complex debugging on the test equipment. Just directly sleeve the spring onto the test shaft, and the fatigue test can be quickly carried out. For example, the spring fatigue testing machine of the patent technology with the publication number of CN106442184A applied by the inventor at an early stage.

[0003] However, for special springs such as flat springs, especially flat springs used in firearms, the above-mentioned equipment cannot be used normally. Since such flat springs are directly installed in the gun magazine during use, in order to simulate the real use environment, the flat spring cannot be sleeved and fixed during the test. This requires that the space size of each flat spring test chamber be extremely matched with the flat spring. Otherwise, if it is too large, it will cause the flat spring to be skewed during the test, resulting in distorted test results or even test damage. Therefore, before testing different models of flat springs, it is necessary to adjust parameters such as the width and thickness of the test chamber to conform to the shape and size of the flat spring to be tested. However, during the test, not only a single flat spring is tested, but several flat springs are tested batchwise at the same time, and each test chamber is an independent space. Therefore, when debugging the parameters of each test chamber, corresponding gaskets need to be designed according to the specific size of the flat spring, and then the gaskets are correspondingly installed in each test chamber. The whole process is very time-consuming and cumbersome; even during the installation process, due to factors such as the accuracy of the gasket itself and installation errors, it is very difficult to debug each test chamber uniformly, resulting in large deviations in the test results of each flat spring. Summary of the Invention

[0004] The present invention aims to provide a multi-functional spring fatigue testing machine to solve the problem that the equipment debugging before flat spring testing is time-consuming and cumbersome.

[0005] To achieve the above object, the present invention adopts the following technical solutions: a multi-functional spring fatigue testing machine, including a testing frame, a flat spring mounting device and a testing device mounted on the testing frame. The flat spring mounting device includes a mounting box body, and a plurality of testing chambers for accommodating flat springs are provided in the mounting box body. A cover plate for closing each testing chamber is provided on the top of the mounting box body. The flat spring mounting device further includes a space adjusting mechanism for adjusting the size of the space in the testing chamber. The space adjusting mechanism includes a width adjusting unit and a thickness adjusting unit; the testing device includes a testing shaft reciprocally slidably connected in each testing chamber and a driving mechanism for controlling the sliding of the testing shaft, and a stroke adjusting mechanism for adjusting the stroke size of the testing shaft is provided on the driving mechanism.

[0006] Preferably, as an improvement, the width adjusting unit includes width adjusting components provided on the side walls of each testing chamber and a width driving part for controlling the width adjusting components. The width adjusting components include two adjusting blocks, the two adjusting blocks are slidably connected to each other in the mounting box body in opposite directions, a wedge-shaped groove is formed between the two adjusting blocks, and a reset component is provided between the two adjusting blocks; the width driving part includes a connecting plate and a plurality of reciprocating width driving blocks. One end of each width driving block is wedge-shaped and reciprocally slides in the wedge-shaped groove, and the other end thereof is located outside the mounting box body and is fixedly connected to the connecting plate.

[0007] Preferably, as an improvement, the thickness adjusting unit includes a thickness block and a thickness driving part for driving the thickness block to move. The thickness block is slidably connected to the side walls of each testing chamber and is located between the two width adjusting components. The thickness driving part includes a thickness push plate and two thickness driving shafts rotatably mounted on the testing frame. The two thickness driving shafts are respectively located on both sides of the mounting box body. Both ends of the thickness push plate are threadedly connected to the two thickness driving shafts, and each thickness block is fixedly connected to the thickness push plate.

[0008] Preferably, as an improvement, a stroke plate is connected to the end of the testing shaft away from the testing chamber. The driving mechanism includes a rotary power unit and a stroke connecting rod. One end of the stroke connecting rod is connected to the rotary power unit, and the other end thereof is rotatably connected to the stroke plate.

[0009] Preferably, as an improvement, a displacement unit is provided between the stroke connecting rod and the rotary power unit. The displacement unit includes a support block fixed on the rotary power unit. A displacement lead screw is rotatably provided in the support block. A threaded seat is threadedly connected to the displacement lead screw. A bearing is provided on the side of the threaded seat away from the support block. The stroke connecting rod is sleeved on the bearing.

[0010] Preferably, as an improvement, the stroke adjusting mechanism includes a docking shaft for being clamped with a docking groove, a rotary driving unit for driving the docking shaft to rotate, and a displacement driving unit for adjusting the displacement of the docking shaft.

[0011] Preferably, as an improvement, there are two driving mechanisms, and the two stroke connecting rods are respectively connected to both ends of the stroke plate. The rotary driving unit includes a driving motor and a rotating shaft. Both ends of the rotating shaft are connected with first bevel gears. Second bevel gears meshing with the first bevel gears are connected to both docking shafts. The driving motor is connected to the rotating shaft through a worm and worm gear mechanism; the displacement driving unit is a driving cylinder, and the output end of the driving cylinder is fixedly connected to the rotary driving unit.

[0012] Preferably, as an improvement, it further includes an initial position adjusting mechanism. The initial position adjusting mechanism includes a reciprocating driving mechanism. The reciprocating driving mechanism is connected to a flat spring mounting device, and the flat spring mounting device slides on the test stand through a guide rail.

[0013] Preferably, as an improvement, a fixed frame body is provided outside the test stand, and a shock absorption device is provided between the test stand body and the fixed frame body.

[0014] The advantages of this solution are as follows:

[0015] 1. The equipment debugging is convenient and efficient: Through the width adjusting unit and the thickness adjusting unit in this solution, the widths or thicknesses of several test chambers can be batch-debugged at one time. The whole debugging process takes no more than 5s. Compared with the traditional debugging method which often takes dozens of minutes or even longer, the efficiency is significantly improved; at the same time, the operation process is extremely simple. The debugging personnel only need to easily rotate the width adjusting shaft and the thickness driving shaft to quickly complete all debugging work, greatly saving labor and time costs, and significantly improving the efficiency of the equipment put into use.

[0016] 2. The equipment debugging is accurate: In this solution, by uniformly driving and adjusting the widths or thicknesses of each test chamber through the width adjusting unit and the thickness adjusting unit, the traditional complex adjusting process is simplified, and the risk of errors caused by the mutual influence of multiple links during the adjustment process is reduced from the root. After actual test verification, after debugging with this solution, the parameters of each test chamber are highly consistent, and the deviation can be controlled within a very small range, effectively ensuring the accuracy of the test results of each test chamber and providing a reliable data basis for subsequent data analysis and product quality evaluation.

[0017] 3. Automatic stroke adjustment: By setting a stroke adjustment mechanism in this solution, under normal conditions, the stroke adjustment mechanism is separated from the driving mechanism to ensure that the equipment operation is not interfered. When the stroke needs to be adjusted, only need to start the driving cylinder to move the docking ring upward until it is key-connected to the displacement lead screw, and then start the driving motor to drive the docking ring to rotate. The docking ring drives the stroke connecting rod to move vertically a preset distance through the displacement lead screw, so as to complete the debugging of the stroke size of the test shaft in the test chamber. This automatic stroke adjustment method is not only easy to operate, but also has extremely high adjustment accuracy, and the stroke adjustment error can be controlled within a very small range. Brief Description of the Drawings

[0018] Figure 1 This is the front view of the present invention.

[0019] Figure 2 This is the axonometric view of the internal structure of the present invention (the left travel link is removed).

[0020] Figure 3 This is the top axonometric view of the flat spring mounting device of the present invention.

[0021] Figure 4 is Figure 3 The partial enlarged view of B in

[0022] Figure 5 is Figure 1 The partial enlarged view of A1 in

[0023] Figure 6 This is the axonometric view of the internal structure of the present invention.

[0024] Figure 7 This is the structural schematic diagram of the stroke adjustment mechanism. Detailed Description of the Preferred Embodiments

[0025] The following is a further detailed description through specific embodiments:

[0026] The reference numerals in the accompanying drawings of the specification include: test stand 1, flat spring mounting device 2, width adjustment unit 21, mounting box body 211, test chamber 212, cover plate 213, adjustment block 214, limit block 215, width drive block 216, connecting plate 217, thickness adjustment channel 218, width adjustment bracket 219, thickness adjustment unit 22, thickness block 221, thickness push plate 222, thickness drive shaft 223, pressure sensor 224, opening 225, sliding groove 226, closing block 227, test device 3, test shaft 301, stroke plate 302, stroke link 303, support block 304, rotary power unit 305, displacement lead screw 306, threaded seat 307, docking shaft 308, docking ring 309, rotating shaft 310, first box body 311, second box body 312, first bevel gear 313, second bevel gear 314, drive cylinder 315, drive motor 316, fixed frame body 4, shock absorption spring 5.

[0027] The embodiment is basically as shown in the attached Figures 1-7As shown in the figure: a multi-functional spring fatigue testing machine, including a testing frame 1, a flat spring mounting device 2 and a testing device 3 mounted on the testing frame 1. The flat spring mounting device 2 includes a mounting box body 211. Inside the mounting box body 211, there are multiple testing chambers 212 for accommodating flat springs. On the top of the mounting box body 211, there is a cover plate 213 for closing each testing chamber 212. The flat spring mounting device 2 further includes a space adjusting mechanism for adjusting the size of the space of the testing chamber 212. The space adjusting mechanism includes a width adjusting unit 21 and a thickness adjusting unit 22. The testing device 3 includes a testing shaft 301 vertically and reciprocally slidably connected in each testing chamber 212 and a driving mechanism for controlling the sliding of the testing shaft 301. A rectangular testing head is detachably connected to the top of the testing shaft 301. The lower ends of each testing shaft 301 are all connected to a stroke plate 302. The driving mechanism includes a rotary power unit 305 and a stroke connecting rod 303. The rotary power unit is a motor or the rotating shaft of the motor after deceleration. The lower end of the stroke connecting rod 303 is connected to the rotary power unit 305, and its upper end is rotatably connected to the stroke plate 302. There are two driving mechanisms, which are respectively vertically connected to both ends of the stroke plate 302, so that the stroke plate 302 can move up and down more stably and prevent vibration.

[0028] As Figures 3-4 shown, the width adjusting unit 21 includes width adjusting components arranged on the side walls of each testing chamber and a width driving part for controlling the width adjusting components. The width adjusting components include two adjusting blocks 214. The adjusting blocks 214 slide horizontally in the mounting box body 211. A wedge-shaped groove is formed between the two adjusting blocks 214. A return spring is provided between the two adjusting blocks 214. On the top surface of the wedge-shaped groove where the two adjusting blocks 214 are located, limit blocks 215 are fixedly installed. The two limit blocks 215 are arranged oppositely. The width of the limit block 215 is greater than the width of the adjusting block 214 at the position where the limit block 215 is located. The purpose of this structure is that when the width driving block 216 withdraws, there is always a certain opening between the two adjusting blocks 214 supported by the limit blocks 215, so that the width driving block 216 can be inserted between the two adjusting blocks 214 smoothly again.

[0029] The width driving part includes a connecting plate 217 and a reciprocating width driving block 216. One end of the width driving block 216 is wedge-shaped and located in the wedge-shaped groove. The other ends of each width driving block 216 are located outside the mounting box body 211 and are detachably connected to the connecting plate 217. In this way, when any width driving block 216 is damaged, only the corresponding one needs to be removed and replaced, without overall disassembly and assembly. In this embodiment, bolt connection is adopted.

[0030] In addition, a thickness adjustment groove is horizontally provided between each width driving block 216 and the connecting plate. Each thickness adjustment groove is located on the same straight line and forms a thickness adjustment channel 218. In this way, when installing the thickness push plate later, it can be installed in this thickness adjustment channel. On the one hand, opening the thickness adjustment groove on the width driving block has a weight reduction effect on the equipment itself. On the other hand, setting the thickness push plate in the thickness adjustment channel makes full use of the limited space and makes the equipment more compact.

[0031] On one side of the installation box body 211 facing the connecting plate, a width adjustment bracket 219 is fixedly installed. A width adjustment shaft is threadedly connected to the width adjustment bracket 219. One end of the width adjustment shaft passes through the width adjustment bracket 219 and is rotatably connected to the connecting plate. An adjustment handle (manual adjustment) or a reduction motor (automatic adjustment) is installed at the outer end of the width adjustment shaft. In addition, as an alternative to automatic adjustment, a reciprocating transmission mechanism, such as a cylinder or an electric telescopic shaft, can be installed on the width adjustment bracket 219. The reciprocating transmission mechanism is fixed on the width adjustment bracket, and its output end is connected to the connecting plate.

[0032] When it is necessary to adjust the width space of each test chamber 212, rotate the adjustment handle to drive the width driving block 216 to slide between the two adjustment blocks 214 through the connecting plate. When the width adjustment block 214 moves deeper into the two adjustment blocks 214, the width of the test chamber 212 decreases, and vice versa.

[0033] As Figures 3-4 shown, the thickness adjustment unit 22 includes a thickness block 221 and a thickness driving part for driving the movement of the thickness block 221. The thickness block 221 is slidably connected to the front and rear side walls of each test chamber 212 and is located between the two width adjustment components. One end of the thickness block 221 is located outside the test chamber 212. The thickness driving part includes two thickness push plates 222 and two thickness driving shafts 223 rotatably installed on the test rack 1. The two ends of each thickness block 221 are respectively fixed on the front and rear thickness push plates 222. The front thickness push plate 222 is located in the thickness adjustment channel 218. Both thickness push plates 222 are threadedly connected to the thickness driving shafts 223. The two threads on the thickness driving shafts 223 have opposite helix directions. When the thickness driving shafts 223 are rotated, the two thickness push plates 222 drive the front and rear thickness blocks 221 to move towards or away from each other, thereby increasing or decreasing the thickness space of the test chamber 212.

[0034] As Figure 5As shown, in order to detect whether the flat spring is abnormal during the test, at least one force testing mechanism is provided on the cover plate 213 in this solution. The force testing mechanism includes an opening 225 formed in the cover plate 213. The opening 225 corresponds to the test chamber 212. Horizontal sliding grooves 226 are formed on both side walls of the cover plate 213 corresponding to the opening 225. A closing block 227 for closing the opening 225 is slidably connected in the sliding grooves 226. The cross-section of the closing block 227 is T-shaped. The bottom surface of the closing block 227 is flush with the bottom surface of the cover plate 213. The thickness of the wing plate of the closing block 227 is less than the height of the sliding groove 226, so that the closing block 227 has a space for vertical displacement in the sliding groove 226. A pressure sensor 224 is slidably connected vertically on the test rack 1. The pressure sensor 224 corresponds to the closing block 227 (one pressure sensor 224 detecting the state of one closing block 227 is shown in the figure). During the entire flat spring test process, the pressure sensor 224 is slid to contact the closing block 227 until after the test is completed, the pressure sensor 224 resets upward to open the closing block 227 and take out the flat spring.

[0035] Through the above ingenious design, the closing block can achieve the following multiple effects simultaneously:

[0036] 1. On the one hand, it can detect whether the flat spring is abnormal: Under normal circumstances, during the test of the flat spring, the flat spring will press against the closing block 227 upward at a certain frequency, causing the closing block 227 to float upward under force and transmit the force to the pressure sensor 224. At this time, the fact that the pressure sensor 224 detects pressure proves that the flat spring is normal. If the flat spring gets stuck in the test chamber 212 or is deformed, the closing block 227 is in a non-force state or a state of infinite force, and then the equipment needs to be shut down for inspection.

[0037] 2. On the other hand, it can play a role in limiting the flat spring to ensure that the flat spring is always in the specified position during the test process and avoid affecting the test results due to displacement.

[0038] 3. On the other hand, it can also play the role of a sliding door. When it is necessary to take in and out the flat spring, the staff only needs to gently slide the closing block 227, and the operation is extremely convenient.

[0039] Such as Figure 6As shown, since the test strokes of flat springs of different models are different, before testing each flat spring, it is necessary to adjust the test stroke of the flat spring. Therefore, in this solution, a displacement unit is provided between the stroke connecting rod 303 and the rotary power unit 305. The displacement unit includes a support block 304. The support block 304 is fixed on the output shaft of the rotary power unit 305. A vertical groove is axially formed in the support block 304. A displacement lead screw 306 is installed in the vertical groove. The displacement lead screw 306 is rotatably connected to the support block 304 through a bracket. A threaded seat 307 is threadedly connected to the displacement lead screw 306. A bearing is provided on the side of the threaded seat 307 away from the support block 304. The lower end of the stroke connecting rod 303 is sleeved on the bearing.

[0040] As Figure 7 shown, in order to make this test system achieve automatic adjustment to improve the stroke adjustment efficiency and convenience, in this solution, a stroke adjustment mechanism for automatically adjusting the stroke size of the test shaft 301 is provided on the drive mechanism. The stroke adjustment mechanism includes a docking shaft 308 for connecting with the displacement lead screw 306, a rotary drive unit for driving the docking shaft 308 to rotate, and a displacement drive unit for adjusting the displacement of the docking shaft 308.

[0041] Specifically: a docking ring 309 is flange-connected to the top of the docking shaft 308, and the docking ring 309 is key-connected to the displacement lead screw 306. The rotary drive unit includes a drive motor 316, a rotating shaft 310, a first box body 311 and a second box body 312. The rotating shaft 310 is rotatably connected in the first box body 311, and first bevel gears 313 are fixedly connected to both ends thereof. The docking shaft 308 is rotatably connected in the second box body 312 through a bearing. A second bevel gear 314 meshing with the first bevel gear 313 is fixedly connected to the lower end of the docking shaft 308. The second box body 312 is communicated with and fixedly connected to the first box body 311. The drive motor 316 is fixed on the first box body 311, and a worm is fixedly connected to its output end. The other end of the worm is rotatably connected to the first box body 311. A worm gear meshing with the worm is sleeved on the middle of the rotating shaft 310; the displacement drive unit is a drive cylinder 315, and the output end of the drive cylinder 315 is fixedly connected to the first box body 311.

[0042] Under normal conditions, the stroke adjustment mechanism is separated from the displacement lead screw. When the stroke needs to be adjusted, the drive cylinder is started to drive the docking ring 309 to move upward through the first box body until it is key-connected to the displacement lead screw 306. Then the drive motor is started to drive the docking ring to rotate through two bevel gears. The docking ring drives the stroke connecting rod to move vertically through the displacement lead screw, so as to complete the debugging of the stroke size of the test shaft in the test chamber.

[0043] According to the different lengths of flat springs of each model, an initial position adjustment mechanism is also designed. The initial position adjustment mechanism includes a reciprocating drive mechanism. In this solution, the reciprocating drive mechanism adopts a lead screw and nut mechanism. The nut seat is connected to the flat spring mounting device 2, and the left and right sides of the flat spring mounting device 2 slide vertically on the test stand 1 through guide rails. When the length of the flat spring is short, the lead screw and nut mechanism drives the flat spring mounting device 2 to move vertically downward until the test shaft 301 abuts against the flat spring.

[0044] In addition, since the vibration of the test stand 1 is relatively large during the entire test process, in order to avoid affecting the ground and surrounding equipment, a fixed frame body 4 is provided outside the test stand 1 in this solution, and shock absorption devices are provided between the test stand 1 body and the fixed frame body 4 except for the front and top surfaces. The shock absorption device is a shock absorption spring 5.

[0045] The above are only embodiments of the present invention. Specific technical solutions and / or common knowledge such as characteristics well known in the art are not described in detail herein. It should be noted that for those skilled in the art, without departing from the technical solution of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicality of the patent. The protection scope required by this application should be based on the content of its claims, and the specific implementation manners described in the specification can be used to explain the content of the claims.

Claims

1. Multifunctional spring fatigue testing machine, characterized in that: It includes a test stand, a flat spring mounting device mounted on the test stand, and a test device. The flat spring mounting device includes a mounting box body. Inside the mounting box body, there are multiple test chambers for accommodating flat springs. On the top of the mounting box body, there is a cover plate for closing each test chamber. The flat spring mounting device further includes a space adjustment mechanism for adjusting the space size of each test chamber. The space adjustment mechanism includes a width adjustment unit and a thickness adjustment unit. The test device includes a test shaft that reciprocally slides in each test chamber and a driving mechanism for controlling the sliding of the test shaft. On the driving mechanism, there is a stroke adjustment mechanism for adjusting the stroke size of the test shaft.

2. The multi-functional spring fatigue testing machine according to claim 1, wherein: The width adjustment unit includes width adjustment components arranged on the side walls of each test chamber and a width driving part for controlling the width adjustment components. The width adjustment components include two adjustment blocks. The two adjustment blocks slide towards each other and are connected inside the mounting box body. A wedge-shaped groove is formed between the two adjustment blocks, and a reset component is provided between the two adjustment blocks. The width driving part includes a connecting plate and multiple reciprocally moving width driving blocks. One end of each width driving block is wedge-shaped and reciprocally slides in the wedge-shaped groove, and the other end is located outside the mounting box body and is fixedly connected to the connecting plate.

3. The multi-functional spring fatigue testing machine according to claim 2, characterized in that: The thickness adjustment unit includes a thickness block and a thickness driving part for driving the movement of the thickness block. The thickness block slides and is connected to the side walls of each test chamber and is located between the two width adjustment components. The thickness driving part includes a thickness push plate and two thickness driving shafts rotatably mounted on the test stand. The two thickness driving shafts are respectively located on both sides of the mounting box body. The two ends of the thickness push plate are threadedly connected to the two thickness driving shafts, and each thickness block is fixedly connected to the thickness push plate.

4. The multi-functional spring fatigue testing machine according to claim 3, characterized in that: One end of the test shaft away from the test chamber is connected to a stroke plate. The driving mechanism includes a rotational power unit and a stroke connecting rod. One end of the stroke connecting rod is connected to the rotational power unit, and the other end is rotatably connected to the stroke plate.

5. The multi-functional spring fatigue testing machine according to claim 4, wherein: A displacement unit is provided between the stroke connecting rod and the rotational power unit. The displacement unit includes a support block fixed to the rotational power unit. Inside the support block, a displacement lead screw is rotatably provided. A threaded seat is threadedly connected to the displacement lead screw. A bearing is provided on the side of the threaded seat away from the support block. The stroke connecting rod is sleeved on the bearing.

6. The multi-functional spring fatigue testing machine according to claim 5, wherein: The stroke adjustment mechanism includes a docking shaft for being clamped with a docking groove, a rotational driving unit for driving the rotation of the docking shaft, and a displacement driving unit for adjusting the displacement of the docking shaft.

7. The multi-functional spring fatigue testing machine according to claim 6, wherein: There are two driving mechanisms. The two stroke connecting rods are respectively connected to both ends of the stroke plate. The rotational driving unit includes a driving motor and a rotating shaft. First bevel gears are connected to both ends of the rotating shaft. Second bevel gears meshing with the first bevel gears are connected to both docking shafts. The driving motor is connected to the rotating shaft through a worm and worm gear mechanism. The displacement driving unit is a driving cylinder, and the output end of the driving cylinder is fixedly connected to the rotational driving unit.

8. The multifunctional spring fatigue testing machine according to claim 7, characterized in that: It further includes an initial position adjustment mechanism. The initial position adjustment mechanism includes a reciprocating driving mechanism. The reciprocating driving mechanism is connected to the flat spring mounting device. The flat spring mounting device slides on the test stand through a guide rail.

9. The multi-functional spring fatigue testing machine according to claim 8, wherein: A fixed frame body is provided outside the test stand. A shock absorption device is provided between the test stand body and the fixed frame body.

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