Plate tension and compression fatigue buckling-preventing device

Abstract

The utility model discloses a plate tension and compression fatigue buckling prevention device, which belongs to the technical field of plate detection, and comprises a testing machine wedge-shaped mechanism, a bending and stretching prevention mechanism and a plate body, the bending and stretching prevention mechanism comprises a first clamping plate and a second clamping plate and is positioned in the testing machine wedge-shaped mechanism; the plate body is located between the first clamping plate and the second clamping plate, the first clamping plate and the second clamping plate are each provided with a plurality of first threaded holes, and the first threaded holes in the first clamping plate correspond to the first threaded holes in the second clamping plate in a one-to-one mode and are connected through first bolts. An extensometer mechanism is further arranged on the side face of the bending and stretching prevention mechanism. By using the device, large friction force generated by direct contact between the buckling-restrained mechanism and the plate body can be avoided, the extensometer mechanism cannot be interfered, the device is suitable for the plate bodies with different thicknesses, and it is guaranteed that the plate body is always kept in a centering state in the test process.

Description

Technical Field

[0001] The utility model relates to the technical field of plate detection, and particularly relates to a plate tensile and compressive fatigue anti-buckling device. Background Art

[0002] In the prior art, fatigue is an important mechanical property parameter of materials. Testing the fatigue performance of raw materials is of great significance for predicting the service performance of structural components. However, for thin plates about 1-2 mm thick, during axial constant amplitude low-cycle fatigue tests, due to the small thickness of the material, the stiffness of the fatigue specimen is insufficient, and the phenomenon of fatigue specimen buckling is very likely to occur during the test, resulting in test failure and even damage to the extensometer and fatigue testing machine. Although adjusting the shape and size of the specimen can reduce the possibility of buckling to a certain extent, buckling cannot be avoided as the specimen thickness decreases.

[0003] Chinese patent with the publication number CN213956993U discloses a plate low-cycle fatigue specimen anti-buckling fixture, which includes two identical A-type jaws a and b, two identical B-type jaws a and b, and two identical positioning pins a and b. It is characterized in that the fatigue specimen is clamped at the test station of the fatigue testing machine through the combination of A-type jaws a, b and B-type jaws a, b, and the two positioning pins a and b ensure the vertical alignment of the fatigue specimen. The front baffle of A-type jaw a and the front baffle of B-type jaw b, and the front baffle of A-type jaw b and the front baffle of B-type jaw a cooperate with each other to prevent the fatigue specimen from buckling during the compression process.

[0004] Regarding the above related technologies, the inventor believes that the following problems exist:

[0005] 1. Relying on symmetric metal baffles to clamp the plate specimen, it is difficult to eliminate the friction between them, thus affecting the actual axial force and ultimately leading to the inaccuracy of the test life result;

[0006] 2. For the structure of the extensometer installation part, only a little gap is reserved, so it is easy to contact the fixture when installing the extensometer, and instability is likely to occur during the strain control test;

[0007] 3. The fixture structure is fixed and cannot be flexibly adjusted for plate specimens of different thicknesses;

[0008] 4. When installing the specimen to ensure alignment, positioning pins are used. However, for plate specimens of different widths, pin holes need to be drilled at different positions of the fixture during installation, and high geometric tolerances are required to ensure the alignment of subsequent specimen installation, increasing the difficulty of machining.

[0009] Therefore, it is urgent to design a new plate tensile and compressive fatigue anti-buckling device to solve the above problems. Utility Model Content

[0010] The purpose of the present utility model is to provide a buckling prevention device for sheet material tensile and compressive fatigue, so as to solve the problems existing in the existing buckling prevention device for sheet material tensile and compressive fatigue. The existing device relies on symmetric metal baffles to clamp the sheet material specimen, making it difficult to eliminate the friction between the two, thus affecting the actual axial force and further affecting the accuracy of the test life result. The small gap will cause the extensometer to contact the fixture when installed. The fixture structure is fixed, resulting in the inability to flexibly adjust sheet material specimens with different thicknesses. When installing sheet material specimens with different widths, pin holes need to be drilled at different positions of the fixture, which requires high geometric tolerances to ensure the centering of the subsequent specimen installation, thereby increasing the machining difficulty.

[0011] To solve the above technical problems, the present utility model provides a buckling prevention device for sheet material tensile and compressive fatigue, including a testing machine wedge mechanism, a buckling prevention mechanism, and a sheet material body. The buckling prevention mechanism includes a first clamping plate and a second clamping plate and is located in the testing machine wedge mechanism. The sheet material body is located between the first clamping plate and the second clamping plate. A plurality of first threaded holes are opened on both the first clamping plate and the second clamping plate. The plurality of first threaded holes on the first clamping plate correspond to the plurality of first threaded holes on the second clamping plate one by one and are all connected by first bolts. Groove openings are also opened on the first clamping plate and the second clamping plate.

[0012] An extensometer mechanism is further provided on the side of the buckling prevention mechanism.

[0013] Optionally, the testing machine wedge mechanism includes a type A jaw, a type B jaw, a type C jaw, and a type D jaw, wherein the type A jaw cooperates with the type B jaw, and the type C jaw cooperates with the type D jaw.

[0014] Optionally, grooves adapted to the sheet material body are opened on the inner sides of both the first clamping plate and the second clamping plate, and fixing blocks are fixed on both sides of the bottom ends thereof. Second threaded holes are opened on the sides of the fixing blocks, and second bolts are threadedly connected in the second threaded holes. The other ends of the two second bolts are respectively threadedly connected with the type C jaw and the type D jaw.

[0015] Optionally, a rubber film is provided in the groove.

[0016] Optionally, the extensometer mechanism includes an extensometer and a travel rod. Two connecting rods are fixed on the side of the extensometer. One ends of the two connecting rods are both connected to the first clamping plate through a connecting plate, and the travel rod is fixed on the two connecting rods.

[0017] Optionally, washers are sleeved on a plurality of the first bolts, and the washers are located between the first clamping plate and the second clamping plate.

[0018] Optionally, both the first clamping plate and the second clamping plate are of I-shaped structures.

[0019] In a plate tension-compression fatigue anti-buckling device provided by the present utility model, it includes a testing machine wedge mechanism, an anti-flexion and extension mechanism, and a plate body. The anti-flexion and extension mechanism includes a first clamping plate and a second clamping plate and is located in the testing machine wedge mechanism. The plate body is located between the first clamping plate and the second clamping plate. A plurality of first threaded holes are opened on both the first clamping plate and the second clamping plate. The plurality of first threaded holes on the first clamping plate correspond to the plurality of first threaded holes on the second clamping plate one by one and are all connected by first bolts. An extensometer mechanism is also provided on the side of the anti-flexion and extension mechanism. Using this device, it can avoid direct contact between the anti-buckling mechanism and the plate body to generate a large frictional force and will not interfere with the extensometer mechanism, and is applicable to plate bodies of different thicknesses, ensuring that the plate body always maintains a centered state during the test. Description of the Drawings

[0020] Figure 1 is a schematic structural diagram of the plate tension-compression fatigue anti-buckling device provided by the present utility model;

[0021] Figure 2 is a partial structural schematic diagram of the plate tension-compression fatigue anti-buckling device provided by the present utility model;

[0022] Figure 3 is a schematic structural diagram of the first clamping plate provided by the present utility model. Detailed Embodiment

[0023] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0024] It should be noted that when a component is referred to as being "fixed to" another component, it can be directly on the other component or there can also be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component at the same time. When a component is considered to be "disposed on" another component, it can be directly disposed on the other component or there may be an intermediate component at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this utility model belongs. The terms used in the description of this utility model herein are only for the purpose of describing specific embodiments and are not intended to limit this utility model. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0026] This utility model provides a buckling prevention device for sheet metal tension-compression fatigue, and its structure is as Figures 1 to 3 shown, including a testing machine wedge mechanism 1, an anti-flexion and extension mechanism 2, and a sheet metal body 9. The anti-flexion and extension mechanism 2 includes a first clamping plate 21 and a second clamping plate 22 and is located in the testing machine wedge mechanism 1. The sheet metal body 9 is located between the first clamping plate 21 and the second clamping plate 22. A number of first threaded holes 27 are opened on both the first clamping plate 21 and the second clamping plate 22. The number of first threaded holes 27 on the first clamping plate 21 corresponds one by one to the number of first threaded holes 27 on the second clamping plate 22 and are all connected by first bolts 3. Notches 25 are also opened on the first clamping plate 21 and the second clamping plate 22, ensuring that the anti-buckling 2 does not interfere with the extensometer mechanism 6 during the test. An extensometer mechanism 6 is also provided on the side of the anti-flexion and extension mechanism 2. Using the buckling prevention device for sheet metal tension-compression fatigue can avoid large frictional forces generated by direct contact between the anti-buckling mechanism 2 and the sheet metal body 9 and will not interfere with the extensometer mechanism 6, and is applicable to sheet metal bodies 9 of different thicknesses, ensuring that the sheet metal body always remains in a centered state during the test.

[0027] Specifically, the testing machine wedge mechanism 1 includes a type A jaw 11, a type B jaw 12, a type C jaw 13, and a type D jaw 14, where the type A jaw 11 cooperates with the type B jaw 12, and the type C jaw 13 cooperates with the type D jaw 14, so that.

[0028] Furthermore, grooves 23 adapted to the sheet metal body 9 are opened on the inner sides of both the first clamping plate 21 and the second clamping plate 22, and fixing blocks 4 are fixed on both sides of the bottom ends thereof. Second threaded holes 26 are opened on the sides of the fixing blocks 4, and second bolts 5 are threadedly connected in the second threaded holes 26. The other ends of the two second bolts 5 are respectively threadedly connected to the type C jaw 13 and the type D jaw 14, and the tops of the first clamping plate 21 and the second clamping plate 22 are respectively fixedly connected to the type A jaw 11 and the type B jaw 12.

[0029] Furthermore, a rubber film 24 is provided in the groove 23, avoiding large frictional forces generated by direct contact between the anti-buckling mechanism 2 and the sheet metal body 9.

[0030] Specifically, the extensometer mechanism 6 includes an extensometer 61 and a travel rod 7. Two connecting rods 62 are fixed to the side of the extensometer 61. One end of each of the two connecting rods 62 is connected to the first clamping plate 21 through a connecting plate 63, and the travel rod 7 is fixed to the two connecting rods 62.

[0031] Further, washers 8 are sleeved on several first bolts 3. The washers 8 are located between the first clamping plate 21 and the second clamping plate 22, which facilitates the testing of the sheet body 9 with different thicknesses.

[0032] Further, both the first clamping plate 21 and the second clamping plate 22 are of I-shaped structures.

[0033] The working principle of the present utility model is as follows: By providing a rubber film 24 between the anti-buckling mechanism 2 and the sheet body 9, direct contact between the two is avoided, thus generating a large frictional force. Moreover, notches 25 are provided on the first clamping plate 21 and the second clamping plate 22, ensuring that the anti-buckling mechanism 2 does not interfere with the extensometer mechanism 6 during the test. And by symmetrically installing several first bolts 3 on the first clamping plate 21 and the second clamping plate 22, the fixing requirements for sheet bodies of different thicknesses can be achieved through different washers 8. Additionally, the position of the sheet body 9 is in the middle of the wedge mechanism 1 of the testing machine, ensuring that it remains in a centered state throughout the test, further guaranteeing the effectiveness of the test results.

[0034] The above description is only a description of the preferred embodiments of the present utility model and does not limit the scope of the present utility model in any way. Any changes and modifications made by those of ordinary skill in the field of the present utility model based on the above disclosure fall within the protection scope of the claims.

Claims

1. A plate tension and compression fatigue anti-buckling device, characterized in that: The invention comprises a testing machine wedge mechanism (1), an anti-bending and stretching mechanism (2) and a plate body (9), wherein the anti-bending and stretching mechanism (2) comprises a first clamping plate (21) and a second clamping plate (22) and is located in the testing machine wedge mechanism (1), and the plate body (9) is located between the first clamping plate (21) and the second clamping plate (22), and the first clamping plate (21) and the second clamping plate (22) are both provided with a plurality of first threaded holes (27), and the plurality of first threaded holes (27) on the first clamping plate (21) correspond to the plurality of first threaded holes (27) on the second clamping plate (22) in a one-to-one manner and are both connected by a first bolt (3), and the first clamping plate (21) and the second clamping plate (22) are also provided with a notch (25); An extensometer mechanism (6) is also provided on the side of the anti-flexion mechanism (2).

2. The plate tension and compression fatigue anti-buckling device according to claim 1, characterized in that: The testing machine wedge mechanism (1) comprises an A-type jaw (11), a B-type jaw (12), a C-type jaw (13) and a D-type jaw (14), wherein the A-type jaw (11) cooperates with the B-type jaw (12), and the C-type jaw (13) cooperates with the D-type jaw (14).

3. The plate tension and compression fatigue anti-buckling device according to claim 2, characterized in that: The first clamping plate (21) and the second clamping plate (22) are each provided with a groove (23) adapted to the plate body (9) on their inner sides, and fixed blocks (4) are fixed on both sides of their bottom ends, and the fixed blocks (4) are provided with a second threaded hole (26) on the side, and a second bolt (5) is threadedly connected in the second threaded hole (26), and the other ends of the two second bolts (5) are respectively threadedly connected to the C-shaped jaw (13) and the D-shaped jaw (14).

4. The plate tension and compression fatigue anti-buckling device according to claim 3, characterized in that: A rubber film (24) is arranged in the groove (23).

5. The plate tension and compression fatigue anti-buckling device according to claim 1, characterized in that: The extensometer mechanism (6) comprises an extensometer (61) and a travel rod (7), two connecting rods (62) are fixed on the side of the extensometer (61), one end of the two connecting rods (62) are connected to the first clamping plate (21) through a connecting plate (63), and the travel rod (7) is fixed on the two connecting rods (62).

6. The plate tension and compression fatigue anti-buckling device according to claim 1, characterized in that: A plurality of the first bolts (3) are each sleeved with a washer (8), and the washer (8) is located between the first clamping plate (21) and the second clamping plate (22).

7. The plate tension and compression fatigue anti-buckling device according to claim 1, characterized in that: The first clamping plate (21) and the second clamping plate (22) are both I-shaped structures.

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