Bending fatigue test device and bending fatigue test system

Abstract

This disclosure relates to the field of fatigue testing, specifically to a bending fatigue testing apparatus and a bending fatigue testing system. The bending fatigue testing apparatus includes a test bench, a fixing fixture, and a loading fixture. The fixing fixture has two limiting ends spaced apart along a first direction, and the two limiting ends are connected to the test bench. The fixing fixture is movable relative to the test bench along a second direction to adjust the distance between the fixing fixture and the test bench. The test bench and the loading fixture are arranged sequentially along a third direction, and the loading fixture is movably arranged in the second direction, used to move the test piece along the second direction. The first direction is perpendicular to the second direction, and the third direction is perpendicular to both the first and second directions. By implementing the bending fatigue testing apparatus and system of the exemplary embodiments of this disclosure, cantilever bending fatigue tests can be performed on test pieces to test their bending fatigue performance.

Description

Technical Field

[0001] This disclosure relates to the field of fatigue testing, and more specifically, to a bending fatigue testing apparatus and a bending fatigue testing system. Background Technology

[0002] Fatigue failure is one of the main causes of structural and mechanical failures in engineering projects. Approximately 50% to 90% of structural failures in engineering are caused by fatigue failure. Therefore, obtaining the fatigue life of components is a fundamental requirement for the use of engineering structures and mechanical parts. Understanding the fatigue strength of components can predict their service life and help determine their safe service life and maintenance cycle, thereby ensuring their safe use.

[0003] Many large and complex equipment components are subjected to cantilever bending loads during use, and their components are in a swaying state. Therefore, it is crucial to evaluate the fatigue performance of components by conducting cantilever bending fatigue tests.

[0004] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] The purpose of this disclosure is to provide a bending fatigue testing apparatus and a bending fatigue testing system that can be used to perform cantilever bending fatigue tests.

[0006] According to one aspect of this disclosure, a bending fatigue testing apparatus is provided, comprising:

[0007] Test bench;

[0008] The fixed fixture has two limiting ends spaced apart along a first direction and connected to the test bench; the fixed fixture can move relative to the test bench along a second direction to adjust the distance between the fixed fixture and the test bench.

[0009] The loading fixture, the test bench, and the loading fixture are arranged sequentially along a third direction. The loading fixture is movably arranged in a second direction and is used to move the test piece along the second direction.

[0010] The first direction is perpendicular to the second direction, and the third direction is perpendicular to both the first and second directions.

[0011] In one exemplary embodiment of this disclosure, each limiting end is connected to the test bench via at least two connectors distributed sequentially along a third direction.

[0012] In one exemplary embodiment of this disclosure, the fixing clamp is detachably connected to the test bench via a connector.

[0013] In one exemplary embodiment of this disclosure, the loading fixture has a first position and a second position when it moves along a second direction;

[0014] The first and second positions are located on both sides of the test platform along the second direction, respectively.

[0015] In one exemplary embodiment of this disclosure, the number of fixing clamps and loading clamps are equal, the fixing clamps are distributed along a first direction, and the loading clamps are distributed along a first direction;

[0016] Each fixed fixture is used to hold a test specimen between the fixed fixture and the test bench; each loading fixture is used to move a test specimen along the second direction.

[0017] In one exemplary embodiment of this disclosure, the bending fatigue testing device further includes a loading head, with loading fixtures connected to the loading head. The loading head is connected to a power mechanism, which drives the loading head to move along a second direction.

[0018] In one exemplary embodiment of this disclosure, the loading fixture includes:

[0019] The first roller has two ends rotatably connected to the loading head and extends along a first direction;

[0020] The second roller has two ends rotatably connected to the loading head and extends along the first direction;

[0021] The first roller and the second roller are arranged sequentially along the second direction, and the first roller and the second roller drive the test piece held between the first roller and the second roller to move along the second direction.

[0022] In one exemplary embodiment of this disclosure, the bending fatigue testing apparatus further includes:

[0023] The displacement acquisition unit is used to acquire the distance the loading head moves along the second direction;

[0024] The load acquisition unit is used to acquire the load of the loading head on the test specimen;

[0025] The processing unit is used to generate a displacement-load curve based on the distance the loading head moves along the second direction and the load on the test specimen.

[0026] In one exemplary embodiment of this disclosure, the bending fatigue testing apparatus further includes:

[0027] Base plate;

[0028] Vertical support;

[0029] Inclined support;

[0030] The vertical support and the inclined support are fixedly connected at one end, and the other end is connected to different positions on the base plate. The test platform is fixed to the end where the vertical support and the inclined support are connected.

[0031] According to another aspect of this disclosure, a bending fatigue testing system is provided, comprising:

[0032] Power mechanism;

[0033] The bending fatigue testing device of any of the above is connected to the power mechanism for driving;

[0034] The test specimen is clamped in the bending fatigue testing device.

[0035] The bending fatigue testing apparatus and system of this disclosure, according to exemplary embodiments, can be used to perform cantilever bending fatigue tests on test specimens to test their bending fatigue performance. Simultaneously, it liberates the axial degree of freedom of the test specimen during bending, achieving a pure bending condition and eliminating the influence of axial force on the bending fatigue test results. Furthermore, the loading fixture applies a load to the unclamped end of the test specimen, eliminating the need for a fixed loading point. Therefore, conventional tensile fatigue testing machines can be used, simplifying the equipment required for the test, reducing costs, and improving the applicability of the bending fatigue testing apparatus. Attached Figure Description

[0036] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0037] To better understand this disclosure, reference may be made to the embodiments shown in the following figures. Components in the figures are not necessarily to scale, and related elements may be omitted to emphasize and clearly illustrate the technical features of this disclosure. Additionally, related elements or components may have different arrangements as known in the art. Furthermore, in the figures, the same reference numerals denote the same or similar components in various figures. Wherein:

[0038] Figure 1 The schematic diagram illustrates a structural schematic of a bending fatigue device according to an exemplary embodiment of the present disclosure;

[0039] Figure 2 The schematic diagram illustrates a structural schematic of a loading fixture according to an exemplary embodiment of the present disclosure.

[0040] The annotations in the attached figures are explained as follows:

[0041] 1. Test specimen; 10. Test bench; 20. Fixing fixture; 30. Loading fixture; 31. First roller; 32. Second roller; 40. Connecting piece; 50. Loading head; 51. Tie rod; 52. Support rod; 60. Base plate; 70. Vertical support; 80. Inclined support; 90. Horizontal support. Detailed Implementation

[0042] The technical solutions in the exemplary embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. The exemplary embodiments described herein are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure. Therefore, it should be understood that various modifications and changes can be made to the exemplary embodiments without departing from the scope of protection of this disclosure.

[0043] Unless otherwise specified or stated, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0044] Furthermore, it should be understood that the directional terms such as "up," "down," "left," and "right" described in the exemplary embodiments of this disclosure are for convenience only, for example, based on the angles shown in the accompanying drawings, and should not be construed as limiting the exemplary embodiments of this disclosure.

[0045] The inventors discovered that in some cantilever bending fatigue test procedures, clamping the test specimen typically requires fixing one end and then loading the other end. However, the test specimen is subjected not only to bending moment but also to axial force, thus no longer a purely bending condition. For some engineering components, such as flexible rocker arms, the structure itself is not subjected to axial force. In experiments, the influence of axial force on the test results leads to inaccurate bending fatigue test results and insufficient reliability in predicting the fatigue life of such engineering components.

[0046] The purpose of this disclosure is to provide a bending fatigue testing apparatus and a bending fatigue testing system capable of performing cantilever bending fatigue tests. The following is in conjunction with the accompanying drawings. Figures 1 to 2 The bending fatigue testing apparatus and bending fatigue testing system disclosed herein are described in detail.

[0047] According to one aspect of this disclosure, a bending fatigue testing apparatus is provided, comprising: a test bench 10, a fixing fixture 20, and a loading fixture 30. The fixing fixture 20 has two limiting ends spaced apart along a first direction, and the two limiting ends are connected to the test bench 10. The fixing fixture 20 is movable relative to the test bench 10 along a second direction to adjust the distance between the fixing fixture 20 and the test bench 10. The test bench 10 and the loading fixture 30 are arranged sequentially along a third direction, and the loading fixture 30 is movably arranged in the second direction, used to move the test piece 1 along the second direction. The first direction is perpendicular to the second direction, and the third direction is perpendicular to both the first and second directions.

[0048] First, for ease of description and understanding, the spatial relationships of the bending fatigue testing device structure of this disclosure are defined and explained. The first direction, second direction, and third direction mentioned above are three mutually perpendicular directions in space. For example, refer to... Figure 1 As shown, in the spatial rectangular coordinate system XYZ: the fixing fixture 20 has two limiting ends spaced apart along the X direction and connected to the test bench 10 through the two limiting ends. The fixing fixture 20 can move relative to the test bench 10 along the Z direction. The test bench 10 and the loading fixture 30 are arranged sequentially along the Y direction, and the loading fixture 30 is movable in the Z direction. It should be noted that, unless otherwise specified or stated, in the description of this disclosure, directions such as X direction, Y direction, or Z direction all refer to two directions extending along an axis. For example, the test bench 10 and the loading fixture 30 being arranged sequentially along the Y direction can be as follows: Figure 1 The positional relationship shown can also be that the positions of the test bench 10 and the loading fixture 30 are swapped, that is, the loading fixture 30 is to the left of the test bench 10 in the direction shown in the figure.

[0049] When using the bending fatigue testing apparatus of this disclosure, one end of the test piece 1 can be clamped between the fixed clamp 20 and the test table 10, and clamped between two limiting ends in the X direction. The test piece 1 is clamped by the movement of the fixed clamp 20 in the Z direction. The loading clamp 30 is used to move the end of the test piece 1 that is not clamped by the test table 10 and the fixed clamp 20 in the Z direction, thereby causing the test piece 1 to bend, so that a bending fatigue test can be performed.

[0050] By implementing the bending fatigue testing apparatus of the exemplary embodiment of this disclosure, a bending fatigue test can be performed on the test piece 1 to test its bending fatigue performance. The fixing clamp 20 and the test table 10 restrict the movement of the test piece 1 in the Z direction, while the two limiting ends are located on both sides of the test piece 1 in the X direction, restricting the movement of the limiting ends in the X direction. Therefore, when the test piece 1 is subjected to a Z-direction load from the loading clamp 30 at the other end, it can only move in the Y direction, freeing the Y-direction degree of freedom of the test piece 1, that is, the axial degree of freedom of the test piece 1 when bending, realizing a pure bending condition, and eliminating the influence of axial force on the bending fatigue test results. Moreover, the loading clamp 30 applies a load to the unclamped end of the test piece 1, causing the unclamped end of the test piece 1 to move in the Z direction. Since there is no need to fix the loading point, a conventional tensile fatigue testing machine can be used, making the equipment required for the test simpler, reducing costs, and improving the applicability of the bending fatigue testing apparatus.

[0051] Specifically, the upper surface of the test bench 10 that contacts the test piece 1 can be flat or curved, and can be adaptively adjusted according to the shape of the test piece 1; correspondingly, the lower surface of the fixing clamp 20 that contacts the test piece 1 can also be adapted to the shape of the test piece 1. For example, both the upper surface of the test bench 10 and the lower surface of the fixing clamp 20 are provided with curved grooves, so that the test piece 1 can be more securely installed between the two grooves. In another exemplary embodiment, refer to Figure 1 As shown, the upper surface of the test bench 10 and the lower surface of the fixing fixture 20 are both flat, which can be used to clamp the flat test piece 1.

[0052] Furthermore, in related technologies, tensile or compressive fatigue tests cannot be performed on thin plate-shaped test specimens 1 with a thickness of less than 0.2 mm in the plastic state. Therefore, the bending fatigue testing apparatus of the exemplary embodiment of this disclosure can be used to test the thin plate test specimens 1, and their fatigue performance can be approximately evaluated. The distance between the fixing clamp 20 and the test table 10 is adjustable, thus allowing test specimens 1 of different thicknesses to be clamped, improving the adaptability to the size of the test specimens 1. The adjustment of the distance between the fixing clamp 20 and the test table 10 can be achieved by means of threaded connection or a combination of lead screw and nut, etc.

[0053] The fixing fixture 20 is connected to the test bench 10 via a limiting end, specifically, refer to Figure 1As shown, the fixture 20 can be detachably connected to the test bench 10 via a connector 40 located at the limiting end. For example, the fixture 20 and the test bench 10 are connected by a threaded connector. The limiting end of the fixture 20 has a threaded hole, and the corresponding position on the test bench 10 also has a threaded hole with the same thread specification. When installing the test piece 1, the test piece 1 is first placed on the test bench 10 between the two limiting ends of the fixture 20, then the threaded holes on the fixture 20 and the test bench 10 are aligned, and then connected via the threaded connector; or a double-ended stud is passed through the open holes on the fixture 20 and the test bench 10, and locked with a nut on the upper surface of the fixture 20 and the lower surface of the test bench 10. In this case, on the one hand, it facilitates the assembly and disassembly of the fixture 20 and the test bench 10, and on the other hand, it can simultaneously adjust the distance between the fixture 20 and the test bench 10, thus making the structure simpler. Those skilled in the art will understand that the limiting end and the test bench 10 can also be connected by other means such as riveting or gluing, and this application does not make any special limitation in this regard.

[0054] In one exemplary embodiment of this disclosure, reference is made to Figure 1 As shown, each limiting end is connected to the test bench 10 via at least two connectors 40 distributed sequentially along the third direction. Specifically, the two loading ends are located on both sides of the fixing clamp 20 in the X direction to restrict the movement of the test piece 1 in the X direction. Furthermore, each limiting end is connected to the test bench 10 via at least two connectors 40 distributed along the Y direction, which further makes it difficult for the test piece 1 to move or deflect in the X direction, ensuring that the end of the test piece 1 fixed by the fixing clamp 20 and the test bench 10 can only move in the Y direction.

[0055] The loading fixture 30 moves the test specimen 1 along the Z direction, thereby applying a load to the test specimen 1. This can be achieved by the loading fixture 30 clamping the test specimen 1 and bending it unidirectionally, changing the load magnitude to alter the bending moment of the cantilever; or by the loading fixture 30 clamping the test specimen 1 and causing it to bend bidirectionally.

[0056] For example, in one exemplary embodiment, the loading fixture 30 has a first position and a second position when moving along the Z direction. The first and second positions are located on opposite sides of the test bench 10 along the Z direction. That is, the loading fixture 30 causes the test piece 1 to bend bidirectionally, and the loading fixture 30 applies alternating loads to the test piece 1 to test its fatigue performance.

[0057] In one exemplary embodiment of this disclosure, reference is made to Figure 1As shown, the number of fixed clamps 20 and loading clamps 30 are equal. The fixed clamps 20 are distributed along the first direction, and the loading clamps 30 are also distributed along the first direction. Each fixed clamp 20 is used to hold a test piece 1 between the fixed clamp 20 and the test table 10; each loading clamp 30 is used to move a test piece 1 along the second direction.

[0058] For example, the fixtures 20 are distributed along the X direction, and the test bench 10 also extends along the X direction. Multiple test pieces 1 can be clamped between different fixtures 20 and the test bench 10. Each fixture 20 is used to clamp one end of a test piece 1. At the other end of the test piece 1, multiple loading fixtures 30 are also distributed along the X direction in correspondence with the fixtures 20, and each loads the other end of the corresponding test piece 1 to move along the Z direction, causing the test piece 1 to bend.

[0059] The bending fatigue testing apparatus of the exemplary embodiment of this disclosure includes multiple fixing clamps 20 and multiple loading clamps 30, thus enabling simultaneous testing of multiple test pieces 1 and improving testing efficiency.

[0060] In one exemplary embodiment of this disclosure, reference is made to Figure 1 and Figure 2 As shown, the bending fatigue testing apparatus also includes a loading head 50, and loading fixtures 30 are all connected to the loading head 50. The loading head 50 is connected to a power mechanism, which drives the loading head 50 to move along a second direction. The power mechanism drives multiple loading fixtures 30 to move simultaneously through the loading head 50, loading multiple test pieces 1. This allows multiple test pieces 1 to be subjected to the same load spectrum simultaneously, improving testing efficiency and obtaining multiple sets of data at once, which is beneficial for improving the accuracy of the results.

[0061] In another exemplary embodiment, the loading fixture 30 can also be connected to the power mechanism individually or in groups, so that cantilever bending fatigue tests under different test conditions can be performed simultaneously.

[0062] The power mechanism can be a tensile fatigue testing machine or other device capable of providing a vertical load spectrum. (Reference) Figure 1 and Figure 2 As shown, the power mechanism is connected to the loading head 50. The loading head 50 may have a cylindrical tie rod 51 along the Z direction at one end away from the loading fixture 30. The upper clamp of the tensile testing machine holds the other end of the tie rod 51 and transmits the load to the loading fixture 30.

[0063] In one exemplary embodiment of this disclosure, reference is made to Figure 2As shown, the loading fixture 30 includes a first roller 31 and a second roller 32. The two ends of the first roller 31 are rotatably connected to the loading head 50 and extend along a first direction; the two ends of the second roller 32 are also rotatably connected to the loading head 50 and extend along the first direction. The first roller 31 and the second roller 32 are sequentially arranged along a second direction, and the first roller 31 and the second roller 32 drive the test piece 1, which is clamped between the first roller 31 and the second roller 32, to move along the second direction.

[0064] Specifically, refer to Figure 2 As shown, the first roller 31 and the second roller 32 can be of equal size and aligned in the Z direction. The loading head 50 may include a plurality of support rods 52 extending in pairs in the Z direction. The two ends of the first roller 31 and the two ends of the second roller 32 are respectively rotatably connected to the loading head 50 through bearings sleeved in the support rods 52. The end of the test piece 1 that is not fixed between the fixing fixture 20 and the test table 10 is clamped between the first roller 31 and the second roller 32.

[0065] When the loading head 50 moves in the Z direction, the first roller 31 and the second roller 32 cause the test piece 1 to bend. At the same time, since both the first roller 31 and the second roller 32 can rotate, the first roller 31 and the second roller 32 do not restrict the degree of freedom of the test piece 1 in the Y direction, further avoiding the influence of the axial force in the Y direction of the test piece 1 during the test.

[0066] In one exemplary embodiment of this disclosure, the bending fatigue testing apparatus further includes a displacement acquisition unit, a load acquisition unit, and a processing unit. The displacement acquisition unit is used to acquire the distance the loading head 50 moves along the second direction; the load acquisition unit is used to acquire the load of the loading head 50 on the test piece 1; and the processing unit is used to generate a displacement-load curve based on the distance the loading head 50 moves along the second direction and the load of the loading head 50 on the test piece 1.

[0067] The displacement acquisition unit and load acquisition unit can be displacement sensors and force sensors, respectively, and the processing unit can be a processor with data calculation functions and a computer with a pre-installed program for drawing graphs based on the acquired data. Of course, the above description of the displacement acquisition unit, load acquisition unit, and processing unit is only a description of their functions; their physical structures can be separate or integrated into the same entity, for example, they can be partially or completely integrated into the power mechanism. This disclosure does not impose any special limitations on this.

[0068] When faced with test specimen 1 made of different materials, the strain response of the materials to load varies. For example, when loading strain-softening materials such as plastics and concrete, since their strain reaches its maximum value, further loading will not cause a significant change in stress, and test specimen 1 is prone to sudden failure. Specifically, taking... Figure 1For example, as the loading head 50 moves downward under the drive of the power mechanism, at a certain position, the load on the test piece 1 reaches a certain value and then becomes difficult to increase further, while the deformation of the test piece 1 continues to increase. Therefore, it is necessary to adopt a displacement-controlled loading method and generate a displacement-load curve for the test piece 1, which can more comprehensively reflect the bending fatigue performance of the material.

[0069] In one exemplary embodiment, the power mechanism, such as a tensile fatigue testing machine, has at least a displacement-controlled loading mode and a stress-controlled loading mode, which can control the displacement of the loading head 50 per unit time, or the increase in load on the test piece 1 by the loading head 50 per unit time. It can also switch between different modes.

[0070] In one exemplary embodiment of this disclosure, reference is made to Figure 1 As shown, the bending fatigue testing device also includes a base plate 60, a vertical support 70, and an inclined support 80. The vertical support 70 is fixedly connected to one end of the inclined support 80, and the other ends are respectively connected to different positions on the base plate 60. The test bench 10 is fixed to the end where the vertical support 70 and the inclined support 80 are connected. Thus, the vertical support 70, the inclined support 80, and the base plate 60 form a triangular structure with good rigidity. In another exemplary embodiment, refer to... Figure 1 As shown, the two ends of the test bench 10 are fixed to the connecting ends of two sets of vertical supports 70 and inclined supports 80, forming two sets of triangular stable supports. During cantilever bending fatigue testing, this helps the entire test device maintain stability, preventing swaying and avoiding potential dangers or slight vibrations affecting the test results. The two sets of supports can be further reinforced by horizontal supports 90. The horizontal supports 90 can be connected between the two vertical supports 70.

[0071] According to another aspect of this disclosure, a bending fatigue testing system is provided, including a bending fatigue testing device, a power mechanism, and a test piece 1. The bending fatigue testing device is driven and connected to the power mechanism, and the test piece 1 is clamped in the bending fatigue testing device. Specific embodiments of the bending fatigue device have been described in detail in the foregoing exemplary embodiments and will not be repeated here. The power mechanism can be a tensile fatigue testing machine or other device capable of providing a vertical load spectrum, capable of providing test loads with a certain frequency and stress ratio. Specifically, the test piece 1 can be a rod-shaped or plate-shaped test piece 1, for example, referring to... Figure 1 As shown, the test piece 1 is a thin plate with a thickness of less than 0.2 mm. The width of the end clamped on the test bench 10 and the fixed fixture 20 and the width of the end clamped on the loading fixture 30 can be different, and the material of the test piece 1 can be changed according to the specific test requirements.

[0072] By implementing the bending fatigue testing system of the exemplary embodiments of this disclosure, bending fatigue tests can be performed to test the bending fatigue performance of the test specimen 1. Furthermore, the axial degree of freedom of the test specimen 1 during bending is freed, achieving a pure bending condition and eliminating the influence of axial force on the bending fatigue test results. The power mechanism can be a conventional tensile fatigue testing machine, simplifying the equipment required for the test, reducing costs, and improving the applicability of the bending fatigue testing device.

[0073] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

[0074] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of protection of this disclosure is limited only by the appended claims.

Claims

1. A bending fatigue testing apparatus characterized by comprising: A cantilever bending fatigue test device is used to perform a cantilever bending fatigue test, the bending fatigue test device comprising: a test bench; a fixed clamp having two limiting ends spaced apart along an X direction, the two limiting ends being connected to the test bench; the fixed clamp being movable relative to the test bench along a Z direction to adjust the distance between the fixed clamp and the test bench; a loading clamp, the test bench and the loading clamp being sequentially arranged along a Y direction, the loading clamp being movably arranged along the Z direction, the loading clamp being used to drive a test piece to move along the Z direction; a loading head, the loading clamp being connected to the loading head, the loading head being connected to a power mechanism, the power mechanism being used to drive the loading head to move along the Z direction; wherein the X direction is perpendicular to the Z direction, and the Y direction is perpendicular to both the X direction and the Z direction; the number of the fixed clamps is equal to the number of the loading clamps, the fixed clamps being distributed along the X direction, and the loading clamps being distributed along the X direction; wherein each of the fixed clamps is used to clamp one of the test pieces between the fixed clamp and the test bench; and each of the loading clamps is used to drive one of the test pieces to move along the Z direction; the loading clamp comprising: a first roller, both ends of the first roller being rotatably connected to the loading head, the first roller extending along the X direction; a second roller, both ends of the second roller being rotatably connected to the loading head, the second roller extending along the X direction; the first roller and the second roller being sequentially arranged along the Z direction, the first roller and the second roller driving the test piece clamped between the first roller and the second roller to move along the Z direction.

2. The bending fatigue test apparatus according to claim 1, characterized by Each of the limiting ends is connected to the test bench by at least two connectors sequentially arranged along the Y direction.

3. The bending fatigue test apparatus according to claim 2, characterized by The fixed clamp is detachably connected to the test bench by the connectors.

4. The bending fatigue testing apparatus according to claim 1, characterized by The loading clamp has a first position and a second position when moving along the Z direction; wherein the first position and the second position are respectively located on both sides of the test bench along the Z direction.

5. The bending fatigue test apparatus according to claim 1, characterized by The bending fatigue test device further comprises: a displacement acquisition unit configured to acquire the distance by which the loading head moves along the Z direction; a load acquisition unit configured to acquire the load on the test piece by the loading head; a processing unit configured to generate a displacement-load curve according to the distance by which the loading head moves along the Z direction and the load on the test piece by the loading head.

6. The bending fatigue test apparatus according to claim 1, characterized by The bending fatigue test device further comprises: a base plate; a vertical support; an inclined support; wherein one end of the vertical support and the inclined support is fixedly connected, the other end of the vertical support and the inclined support is respectively connected to different positions of the base plate, and the test bench is fixed to one end of the vertical support and the inclined support.

7. A bending fatigue test system characterized by comprising: comprising: a power mechanism; the bending fatigue test device according to any one of claims 1-6, being drivingly connected to the power mechanism; a test piece, the test piece being clamped in the bending fatigue test device.

Images