Four-point bending test tool

Abstract

The utility model provides a four-point bending test tool, which is used for testing the bending strength of a tested flat plate and comprises two loading mechanisms which are oppositely arranged up and down, and the tested flat plate is clamped between the two loading mechanisms. The loading mechanism comprises an adjusting assembly and a clamping assembly which are telescopically connected in the height direction, one part of the clamping assembly can make contact with the tested flat plate, the adjusting assembly is located on the side, away from the tested flat plate, of the clamping assembly, and the adjusting assembly can drive the clamping assembly to move in the horizontal direction. The four-point bending test tool solves the problems that a four-point bending test tool in the prior art is difficult to install and debug and large in measurement error.

Description

Technical Field

[0001] The utility model relates to the technical field of flat plate strength testing, in particular to a four-point bending testing tool. Background Art

[0002] The flat plate strength test uses a four-point bending test, which needs to meet the standard of line contact and has extremely high requirements for the parallelism of the upper and lower test claws. The existing upper and lower test structures are both hard contacts, and the upper and lower planes in contact with the flat plate must meet the parallelism required for the test. The tooling processing accuracy is extremely high, and it needs to be constantly debugged during installation to meet the test requirements. In addition, there is a big problem with the existing tooling with integrated upper and lower rods. When the test plate itself is not very large, it often breaks. At this time, the test claws of the upper and lower rods will directly touch each other under the additional pressure, which will eventually damage the equipment.

[0003] That is to say, the four-point bending test tooling in the prior art has the problems of difficult installation and debugging and large measurement errors. Utility Model Content

[0004] The main purpose of the utility model is to provide a four-point bending test tool to solve the problems of difficult installation and debugging and large measurement errors of the four-point bending test tool in the prior art.

[0005] In order to achieve the above-mentioned purpose, the utility model provides a four-point bending test fixture, which is used to test the bending strength of a flat plate to be tested. The four-point bending test fixture includes two loading mechanisms arranged relatively up and down, and the flat plate to be tested is clamped between the two loading mechanisms. The loading mechanism includes an adjustment component and a clamping component which are telescopically connected along the height direction, a part of the clamping component can contact the flat plate to be tested, the adjustment component is located on the side of the clamping component away from the flat plate to be tested, and the adjustment component can drive the clamping component to move in the horizontal direction.

[0006] Furthermore, the adjustment component includes: a slide rail extending in a horizontal direction; two sliders symmetrically arranged in an extension direction perpendicular to the slide rail, one end of the slider is slidably connected to the slide rail, and the other end of the slider is telescopically connected to the clamping component.

[0007] Furthermore, the slider has a recessed portion recessed away from the measured plate, and an opening of the recessed portion faces away from another slider located in the same adjustment assembly.

[0008] Furthermore, the slider includes a connecting section and a sliding section which are perpendicular to each other, one side of the sliding section is slidably connected to the slide rail, and the other side of the sliding section is connected to the connecting section, and the connecting section extends toward the clamping assembly to form a recessed portion.

[0009] Furthermore, a side of the connecting section facing the clamping assembly has a mounting groove, and at least a portion of the clamping assembly is telescopically connected in the mounting groove.

[0010] Furthermore, the portion of the clamping assembly extending into the mounting groove has at least one mounting hole, and the connecting section also has at least one adjustment groove extending horizontally from one side of the opening, and the adjustment groove passes through the mounting groove. The adjustment assembly also includes at least one fixing screw, and the fixing screw can pass through the mounting hole from the adjustment groove to fix the clamping assembly and the slider, and the mounting hole, the mounting slot and the fixing screw are arranged in a one-to-one correspondence.

[0011] Furthermore, there are a plurality of mounting holes, and the plurality of mounting holes are spaced apart along the extension direction of the clamping assembly, and the extension direction of the clamping assembly is perpendicular to both the horizontal direction and the height direction.

[0012] Further, along the extension direction of the slide rail, at least one side surface of the slide rail has a scale, the scale is arranged along the extension direction of the slide rail, and the scale is located at the edge of the slide rail close to the slider.

[0013] Furthermore, the loading mechanism also includes a mounting block, which is slidably connected to a side of the slide rail away from the sliding block.

[0014] Furthermore, the clamping assembly includes two clamping parts symmetrically arranged along an extension direction perpendicular to the slide rail, and the clamping parts include: a support rod, one end of the support rod is telescopically connected to the slider, and the other end of the support rod extends in a direction close to the tested plate; a test rod, the test rod is detachably connected to the other end of the support rod, and the extension direction of the test rod is perpendicular to both the horizontal direction and the height direction.

[0015] Furthermore, one end of the support rod close to the measured plate has a bent portion, and the bent portion is bent in a direction close to the symmetry axis of the clamping assembly.

[0016] Furthermore, the loading mechanism also includes a spring, and the spring is arranged between the adjusting assembly and the clamping assembly.

[0017] Furthermore, the four-point bending test fixture also includes a straightening plate, which is used to adjust the parallelism of the contact surfaces of the two loading mechanisms and the tested plate so that the parallelism of the two contact surfaces is less than or equal to 1 micron.

[0018] By applying the technical solution of the utility model, the four-point bending test fixture is used to test the bending strength of the plate to be tested. The four-point bending test fixture includes two loading mechanisms of the four-point bending test fixture that are arranged opposite to each other up and down, and the plate to be tested is clamped between the two loading mechanisms. The loading mechanism includes an adjustment component and a clamping component that are telescopically connected in the height direction, a part of the clamping component can contact the plate to be tested, and the adjustment component is located on the side of the clamping component away from the plate to be tested, and can drive the clamping component to move in the horizontal direction.

[0019] The four-point bending test fixture provided by the present application can be installed on a universal testing machine, and the flat plate to be tested is set between the upper and lower loading mechanisms, and the flat plate to be tested is pressurized by the loading mechanism, so as to test the bending strength of the flat plate to be tested. By setting the clamping assembly to contact the flat plate to be tested, the flat plate to be tested can be directly pressurized, and the adjusting assembly can drive the clamping assembly to move in the horizontal direction, and the contact position of the clamping assembly and the flat plate to be tested can be adjusted, so as to simulate and test different stress conditions. The adjusting assembly and the clamping assembly are telescopically connected in the height direction, and the relative position of the clamping assembly and the adjusting assembly is adjusted, so as to facilitate the debugging of the parallelism of the contact surface between the upper and lower clamping assemblies and the flat plate to be tested, reduce the requirements for the processing accuracy of the four-point bending test fixture, and reduce the requirements for the minimum test size under the relative strength requirements, reduce the measurement error caused by the four-point bending test fixture as much as possible, and facilitate the adjustment of the relative position of the adjusting assembly and the clamping assembly, and improve the installation and debugging efficiency before measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0021] Figure 1 A schematic structural diagram of a four-point bending test tooling according to an optional embodiment of the utility model is shown;

[0022] Figure 2 Shows Figure 1 Schematic diagram of the four-point bending test fixture during the test process;

[0023] Figure 3 Shows Figure 1 A schematic diagram of the coordination of the adjustment component and the clamping component of the four-point bending test fixture;

[0024] Figure 4 Shows Figure 1 A schematic diagram of the structure of the slide rail of the four-point bending test fixture;

[0025] Figure 5 Shows Figure 1 Schematic diagram of the deformation state of the straightening plate when it is subjected to straightening force;

[0026] Figure 6 Shows Figure 1 Comparison chart of the test results and calibration values ​​of the four-point bending test fixture on the calibration product;

[0027] Figure 7 A partial crack of a plate under test in an optional embodiment of the utility model is shown;

[0028] Figure 8 Another part of cracks on a plate under test according to an optional embodiment of the present invention is shown.

[0029] The above drawings include the following reference numerals:

[0030] 10. Loading mechanism; 11. Mounting block; 12. Spring; 20. Adjustment assembly; 21. Slide rail; 211. First slideway; 212. Second slideway; 22. Slider; 23. Connecting section; 24. Sliding section; 25. Mounting groove; 30. Clamping assembly; 31. Clamping part; 32. Support rod; 33. Test rod; 34. Fixing hole; 35. Bending part; 40. Test plate; 50. Straightening plate. DETAILED DESCRIPTION

[0031] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present utility model will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0032] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0033] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above-mentioned directional words are not used to limit the present invention.

[0034] In order to solve the problems in the prior art that a four-point bending test tool is difficult to install and debug and has a large measurement error, the utility model provides a four-point bending test tool.

[0035] like Figures 1 to 8 As shown, the four-point bending test fixture is used to test the bending strength of the plate 40 to be tested. The four-point bending test fixture includes two loading mechanisms 10 arranged opposite to each other up and down, and the plate 40 to be tested is clamped between the two loading mechanisms 10. The loading mechanism 10 includes an adjustment component 20 and a clamping component 30 that are telescopically connected in the height direction, and a portion of the clamping component 30 can contact the plate 40 to be tested. The adjustment component 20 is located on the side of the clamping component 30 away from the plate 40 to be tested, and can drive the clamping component 30 to move in the horizontal direction.

[0036] The four-point bending test fixture provided by the present application can be installed on a universal testing machine, and the plate 40 to be tested is set between the upper and lower loading mechanisms 10, and the loading mechanism 10 is used to pressurize the plate 40 to be tested, thereby testing the bending strength of the plate 40 to be tested. By setting the clamping assembly 30 to contact the plate 40 to be tested, the plate 40 to be tested can be directly pressurized, and the adjustment assembly 20 can drive the clamping assembly 30 to move in the horizontal direction, and the contact position between the clamping assembly 30 and the plate 40 to be tested can be adjusted, thereby simulating and testing different stress conditions. The adjusting assembly 20 and the clamping assembly 30 are telescopically connected in the height direction, and the relative positions of the clamping assembly 30 and the adjusting assembly 20 are adjusted, so as to facilitate debugging of the parallelism of the contact surfaces between the upper and lower clamping assemblies 30 and the tested plate 40, thereby reducing the requirements for the machining accuracy of the four-point bending test fixture, and reducing the requirements for the minimum test size under the relative strength requirements, thereby minimizing the measurement error caused by the four-point bending test fixture, and facilitating the adjustment of the relative positions of the adjusting assembly 20 and the clamping assembly 30, thereby improving the installation and debugging efficiency before measurement.

[0037] like Figure 1 and Figure 2 As shown, the adjustment assembly 20 includes a slide rail 21 extending in the horizontal direction and two sliders 22 symmetrically arranged in a direction perpendicular to the extension of the slide rail 21, one end of the slider 22 is slidably connected to the slide rail 21, and the other end of the slider 22 is telescopically connected to the clamping assembly 30. That is to say, the adjustment assembly 20 is provided with a slide rail 21 extending in the horizontal direction, and the two sliders 22 are symmetrically arranged in a direction perpendicular to the extension of the slide rail 21. Along the extension direction of the slide rail 21, at least a part of the slide rail 21 has a slideway, and one end of the slider 22 contacts the slideway so that the slider 22 slides on the slide rail 21. The slide rail 21 plays a role in flexibly adjusting the horizontal position of the two sliders 22, which can meet the requirements of the four-point bending test fixture to simulate different stress scenarios. The other end of the slider 22 is telescopically connected to the clamping assembly 30, so as to adjust the relative position of the clamping assembly 30 and the slider 22, so that the parallelism of the contact surface between the upper and lower clamping assemblies 30 and the measured plate 40 meets the high-precision requirements, avoiding the measurement error caused by the processing error.

[0038] Specifically, the slider 22 has a concave portion that is concave away from the measured plate 40, and the opening of the concave portion faces away from the other slider 22 located in the same adjustment assembly 20. In other words, from the side of the slider 22 close to the measured plate 40 to the direction away from the measured plate 40, the slider 22 is concave, and from the side of the two sliders 22 facing each other to the opposite side, the slider 22 is also concave. The setting of the concave portion reserves space for the pressure impact of the upper and lower clamping assemblies 30 after the measured plate 40 is broken, which can effectively avoid equipment damage and reduce measurement costs.

[0039] As shown in FIG. 3 , the slider 22 includes a connecting section 23 and a sliding section 24 which are perpendicular to each other. One side of the sliding section 24 is slidably connected to the slide rail 21, and the other side of the sliding section 24 is connected to the connecting section 23. The connecting section 23 extends in a direction close to the clamping assembly 30 to form a recessed portion. In other words, the slider 22 is divided into two functional areas, wherein the sliding section 24 is slidably connected to the slide rail 21. The sliding section 24 slides along the extension direction of the tested flat plate 40, which can meet the requirements of adjusting the relative position of the slider 22 at will and adapt to the diversified flat plate testing requirements. The connecting section 23 is telescopically connected to the clamping assembly 30. The connecting section 23 extends in a direction perpendicular to the extension direction of the tested flat plate 40. At the same time, there is a gap between the connecting section 23 and the sliding section 24 to form a recessed portion.

[0040] Optionally, in order to ensure the consistency of the size of the slider and reduce the error caused by the complexity of the process, the connecting section 23 and the sliding section 24 are integrally formed into the slider 22 .

[0041] like Figure 3 As shown, the connecting section 23 has a mounting groove 25 on one side facing the clamping assembly 30, and at least a portion of the clamping assembly 30 is telescopically connected in the mounting groove 25. The mounting groove 25 is provided to allow at least a portion of the clamping assembly 30 to extend therein. The shape of the portion of the clamping assembly 30 in the mounting groove 25 matches the size of the mounting groove 25, so that the clamping assembly 30 in the mounting groove 25 can be stably telescopically adjusted and fixed.

[0042] Specifically, the portion of the clamping assembly 30 extending into the mounting groove 25 has at least one mounting hole, and the connecting section 23 also has at least one adjustment groove extending horizontally from one side of the opening, and the adjustment groove passes through the mounting groove 25. The adjustment assembly 20 also includes at least one fixing screw, and the fixing screw can pass through the mounting hole from the adjustment groove to fix the clamping assembly 30 and the slider 22. The mounting holes, the mounting groove 25 and the fixing screw are arranged in a one-to-one correspondence. In other words, the number and corresponding positions of the mounting holes and the adjustment grooves are consistent. After at least a portion of the clamping assembly 30 extends into the mounting groove 25, the fixing screw can pass through the mounting hole from the adjustment groove to fix the clamping assembly 30 and the slider 22, which effectively ensures the stability of the clamping assembly 30 and meets the pressure requirements for the use of the tooling.

[0043] Specifically, there are multiple mounting holes, which are spaced apart along the extension direction of the clamping assembly 30, and the extension direction of the clamping assembly 30 is perpendicular to both the horizontal direction and the height direction. The arrangement of multiple mounting holes enhances the stability of the clamping assembly 30 and meets the pressure requirements of various tooling.

[0044] Preferably, the plurality of mounting holes are arranged at equal intervals.

[0045] like Figure 1 and Figure 2 As shown, specifically, along the extension direction of the slide rail 21, at least one side of the slide rail 21 has a scale, the scale is set along the extension direction of the slide rail 21, and the scale is located at the edge of the slide rail 21 close to the slider 22. By setting the scale, it is convenient to record the position and distance between the two sliders 22, so as to realize the loading of different loads.

[0046] like Figure 1 and Figure 2 As shown, the loading mechanism 10 further includes a mounting block 11, which is slidably connected to the side of the slide rail 21 away from the slider 22. The mounting block 11 can slide arbitrarily along the horizontal direction of the tested plate 40. By providing two mounting blocks 11, the detachable requirements of the tooling can be met, which is convenient for connection with the universal testing machine, and at the same time has a sliding function to adapt to various application scenarios.

[0047] Alternatively, if Figure 4 As shown, the slide rail 21 has a first slide track 211 and a second slide track 212 , the mounting block 11 can slide on the first slide track 211 , and the slider 22 can slide on the second slide track 212 .

[0048] like Figure 3 As shown, the clamping assembly 30 includes two clamping parts 31 symmetrically arranged along the extension direction perpendicular to the slide rail 21, and the clamping part 31 includes a support rod 32 and a test rod 33. One end of the support rod 32 is telescopically connected to the slider 22, and the other end of the support rod 32 extends in a direction close to the measured plate 40; the test rod 33 is detachably connected to the other end of the support rod 32, and the extension direction of the test rod 33 is perpendicular to both the horizontal direction and the height direction. That is to say, along the extension direction perpendicular to the slide rail 21, the clamping assembly 30 includes two symmetrically arranged clamping parts 31, and the clamping parts 31 are sequentially provided with the support rod 32 and the test rod 33. One end of the support rod 32 extends into the mounting groove 25, and is telescopically connected to the slider 22, and can be fixed by being telescopically connected with the adjusting groove and the fixing screw, and the other end of the support rod 32 extends toward the measured plate 40, and can fix the test rod 33 at the same time. The test rod 33 is detachably connected to the support rod 32, which is convenient for replacement when worn, and test rods 33 of various diameters can be used, which greatly improves the convenience of the tooling, and the easy replacement reduces the maintenance cost of the tooling. By providing two symmetrical clamping parts 31, two test rods 33 are used to form a test plane to contact one side of the plate 40 to be tested.

[0049] Optionally, both the support rod 32 and the test rod 33 have fixing holes 34 , and tension springs are used to fix both ends to the fixing holes 34 to achieve connection between the support rod 32 and the test rod 33 .

[0050] like Figure 3As shown, the end of the support rod 32 close to the tested flat plate 40 has a bent portion 35, and the bent portion 35 is bent in the direction close to the symmetry axis of the clamping assembly 30. The setting of the bent portion 35 can effectively prevent the support rods 32 located on the upper and lower sides of the tested flat plate 40 from being damaged due to pressure collision after the tested flat plate 40 is broken during the test process, which greatly improves the service life of the tooling.

[0051] like Figure 3 As shown, the loading mechanism 10 also includes a spring 12, which is arranged between the adjustment component 20 and the clamping component 30. This arrangement can make the leveling and positioning of the tooling much easier, and facilitates the precise control of the parallelism of the contact surface between the clamping component 30 and the measured plate 40. At the same time, it greatly reduces the requirements on the size of the workpiece, reduces the cost, and speeds up the debugging and installation. Figure 1 As shown, the four-point bending test fixture also includes a straightening plate 50, which is used to adjust the parallelism of the contact surfaces of the two loading mechanisms 10 and the tested plate 40, so that the parallelism of the two contact surfaces is less than or equal to 1 micron. By leveling the straightening plate 50, the parallelism of the contact surfaces of the loading mechanism 10 and the tested plate 40 is ensured, and the measurement error caused by the loading mechanism 10 itself is avoided.

[0052] The debugging method of the four-point bending test fixture of the present application is as follows: connect the upper and lower mounting blocks 11 to the universal testing machine respectively, place the straightening plate 50 between the two loading mechanisms 10, and loosen the fixing screws of the slider 22 and the support rod 32; control the universal testing machine to move up and down, so that the spring 12 is in a compressed state, and tighten the fixing screws of the slider 22 and the support rod 32. At this point, the debugging is completed. Such debugging greatly reduces the installation time and improves the test accuracy.

[0053] In an optional embodiment, the plate 40 to be tested is glass, and the cracks appearing therein are as follows: Figure 7 and Figure 8 The shown is irregular and not fixed.

[0054] like Figure 5 As shown, it is the deformation state of the straightening plate 50 when subjected to stress during straightening, and the entire deformation amount is 0.076 microns, which can meet the requirement that the parallelism of the two planes where the upper and lower test rods 33 are located is within 1 micron.

[0055] like Figure 6 The results shown are those of the calibration test, which are consistent with the calibration values, indicating that the accuracy is up to standard.

[0056] From the above description, it can be seen that the above embodiments of the utility model achieve the following technical effects:

[0057] 1. By setting the clamping assembly 30 in contact with the plate 40 to be tested, the plate 40 to be tested can be directly pressurized. The adjusting assembly 20 can drive the clamping assembly 30 to move in the horizontal direction, and the contact position between the clamping assembly 30 and the plate 40 to be tested can be adjusted, thereby simulating and testing different stress conditions.

[0058] 2. The adjusting assembly 20 and the clamping assembly 30 are telescopically connected in the height direction, and the relative position of the clamping assembly 30 and the adjusting assembly 20 is adjusted, so as to facilitate the debugging of the parallelism of the contact surfaces between the upper and lower clamping assemblies 30 and the measured plate 40, reduce the processing accuracy requirements of the four-point bending test fixture, and reduce the minimum test size requirements under the relative strength requirements, thereby minimizing the measurement error caused by the four-point bending test fixture. At the same time, it is convenient to adjust the relative position of the adjusting assembly 20 and the clamping assembly 30, thereby improving the installation and debugging efficiency before measurement.

[0059] Obviously, the embodiments described above are only some embodiments of the utility model, not all embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0060] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0061] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0062] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A four-point bending test tool, characterized in that: The four-point bending test fixture is used to test the bending strength of a plate (40) to be tested. The four-point bending test fixture comprises two loading mechanisms (10) arranged opposite to each other in an upper and lower direction. The plate (40) to be tested is clamped between the two loading mechanisms (10). The loading mechanism (10) comprises an adjustment component (20) and a clamping component (30) which are telescopically connected in a height direction. A portion of the clamping component (30) can contact the plate (40) to be tested. The adjustment component (20) is located on a side of the clamping component (30) away from the plate (40) to be tested. The adjustment component (20) can drive the clamping component (30) to move in a horizontal direction.

2. The four-point bending test fixture according to claim 1, characterized in that: The adjustment component (20) comprises: A slide rail (21) extending in a horizontal direction; Two sliding blocks (22) are symmetrically arranged along an extension direction perpendicular to the slide rail (21), one end of the sliding block (22) is slidably connected to the slide rail (21), and the other end of the sliding block (22) is telescopically connected to the clamping assembly (30).

3. The four-point bending test fixture according to claim 2, characterized in that: The slider (22) has a recessed portion that is recessed away from the measured plate (40), and an opening of the recessed portion faces away from another slider (22) located in the same adjustment assembly (20).

4. The four-point bending test fixture according to claim 3, characterized in that: The slider (22) comprises a connecting section (23) and a sliding section (24) which are perpendicular to each other. One side of the sliding section (24) is slidably connected to the slide rail (21), and the other side of the sliding section (24) is connected to the connecting section (23). The connecting section (23) extends in a direction close to the clamping assembly (30) to form the recessed portion.

5. The four-point bending test fixture according to claim 4, characterized in that: The connecting section (23) has a mounting groove (25) on one side facing the clamping assembly (30), and at least a portion of the clamping assembly (30) is telescopically connected in the mounting groove (25).

6. The four-point bending test fixture according to claim 5, characterized in that: The portion of the clamping assembly (30) extending into the mounting groove (25) has at least one mounting hole, and the connecting section (23) also has at least one adjustment groove extending from one side of the opening to the horizontal direction, and the adjustment groove passes through the mounting groove (25). The adjustment assembly (20) also includes at least one fixing screw, and the fixing screw can pass through the mounting hole from the adjustment groove to fix the clamping assembly (30) and the slider (22), and the mounting hole, the mounting groove (25) and the fixing screw are arranged in a one-to-one correspondence.

7. The four-point bending test fixture according to claim 6, characterized in that: There are a plurality of mounting holes, and the plurality of mounting holes are arranged at intervals along the extension direction of the clamping assembly (30), and the extension direction of the clamping assembly (30) is perpendicular to both the horizontal direction and the height direction.

8. The four-point bending test fixture according to claim 2, characterized in that: Along the extension direction of the slide rail (21), at least one side surface of the slide rail (21) has a scale, and the scale is arranged along the extension direction of the slide rail (21), and the scale is located at the edge of the slide rail (21) close to the slider (22).

9. The four-point bending test fixture according to claim 2, characterized in that: The loading mechanism (10) further comprises a mounting block (11), wherein the mounting block (11) is slidably connected to a side of the slide rail (21) away from the slide block (22).

10. The four-point bending test fixture according to claim 2, characterized in that: The clamping assembly (30) comprises two clamping parts (31) symmetrically arranged along an extension direction perpendicular to the slide rail (21), and the clamping parts (31) comprise: A support rod (32), one end of which is telescopically connected to the slider (22), and the other end of which extends in a direction close to the measured plate (40); A test rod (33), the test rod (33) is detachably connected to the other end of the support rod (32), and the extension direction of the test rod (33) is perpendicular to both the horizontal direction and the height direction.

11. The four-point bending test fixture according to claim 10, characterized in that: The support rod (32) has a bent portion (35) at one end close to the measured plate (40), and the bent portion (35) is bent in a direction close to the symmetry axis of the clamping assembly (30).

12. The four-point bending test fixture according to any one of claims 1 to 11, characterized in that: The loading mechanism (10) further comprises a spring (12), wherein the spring (12) is arranged between the adjustment assembly (20) and the clamping assembly (30).

13. The four-point bending test fixture according to any one of claims 1 to 11, characterized in that: The four-point bending test fixture further comprises a straightening plate (50), and the straightening plate (50) is used to adjust the parallelism of the contact surfaces of the two loading mechanisms (10) and the tested plate (40) so that the parallelism of the two contact surfaces is less than or equal to 1 micron.

Images