Self-locking tension test fixture
The self-locking tensile test fixture solves the problem of insufficient adaptability of traditional tensile test fixtures by using a horizontally moving lead screw slide and a self-locking adjustment component, thus achieving stable clamping and efficient testing of different samples.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GUANGDONG HAIXING PLASTIC & RUBBER CO LTD
- Filing Date
- 2025-07-15
- Publication Date
- 2026-07-03
AI Technical Summary
Traditional tensile testing equipment lacks adaptability to specimens of different shapes and sizes in terms of fixture design, resulting in frequent fixture changes, cumbersome operation, and unstable clamping, which affects testing efficiency and accuracy.
A self-locking tensile test fixture is adopted. The position of the clamping components is adjusted by driving the horizontally moving screw slide. Stable clamping is achieved by the self-locking adjustment components of the U-shaped plate and locking block. The fixture includes the cooperation of the threaded rod, pressure block, spring and wedge block. The spring preload is adjusted to adapt to different samples.
It improves the stability and adaptability of clamping, reduces the frequency of clamp replacement, ensures that the sample does not loosen during the test, improves the accuracy and efficiency of the test, and reduces the difficulty of operation and labor intensity.
Smart Images
Figure CN224456378U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of tensile testing equipment, and more specifically, to a self-locking tensile testing fixture. Background Technology
[0002] In the field of tensile testing equipment technology, accurate and efficient evaluation of the tensile properties of materials or components is crucial. With the increasing sophistication of industrial production and the continuous improvement of product quality requirements, more stringent standards have been set for the performance, ease of operation, and testing accuracy of tensile testing devices.
[0003] Traditional tensile testing methods have significant drawbacks in many aspects. Early testing methods relied heavily on manual labor, requiring staff to manually apply tension and observe the test sample's condition in real time. This approach not only consumes a large amount of manpower but also results in large fluctuations in test data and compromises accuracy due to the difficulty in maintaining stable manual force application. For example, when testing the tensile strength of a metal wire, even slight carelessness during manual force application can cause uneven stress on the wire, leading to premature breakage and incorrect test results.
[0004] To address the issues of manual operation, some existing technologies have introduced related tensile testing devices, such as the invention with application number 201711454553.4. This invention provides a tensile testing device comprising a testing platform and a power unit. The testing platform has a horizontally extending working surface, one end of which is fixed with a mounting component for connecting one end of a pull rod; the output end of the power unit is connected to the other end of the working surface and is also fixed to the other end of the pull rod. The power unit provides a preset tensile force to test the pull rod's performance. Compared to purely manual operation, this device improves testing efficiency and data accuracy to a certain extent, and reduces interference from human factors.
[0005] However, such tensile testing devices still have limitations. In terms of fixture design, they lack sufficient adaptability to test samples of different shapes and sizes. Faced with diverse specimens, the device often requires frequent changes of specific fixtures, making operation cumbersome and time-consuming. For example, when testing pipes of different diameters, each change of pipe diameter necessitates replacing the appropriate fixture, significantly impacting testing efficiency. Furthermore, regarding clamping stability, the device's fixtures fix the specimen using only a simple connection method. During the test, especially when the tensile force approaches the specimen's ultimate bearing capacity, the specimen is prone to loosening or even falling off, leading to test interruption, wasting time and resources, and potentially damaging the testing equipment. Utility Model Content
[0006] The purpose of this invention is to provide a self-locking tensile test fixture to solve the problem mentioned in the background art that the fixture design lacks sufficient adaptability to test samples of different shapes and sizes.
[0007] To achieve the above objectives, this utility model provides a self-locking tensile test fixture, including a horizontally moving lead screw slide, a movable seat, and a clamping component. The clamping component is mounted on one side of the movable seat, which is driven to move horizontally by the horizontally moving lead screw slide. The clamping component clamps and fixes the tensile test piece by self-locking. The clamping component encloses a U-shaped plate, and two symmetrical locking blocks are movably arranged inside the opening of the U-shaped plate. The back of the locking blocks is adjusted and pressure is applied by a self-locking adjustment component, thereby clamping and fixing the tensile test piece through the clamping surface on the front of the locking blocks.
[0008] This setup allows for flexible adjustment of the position of the tensile test piece by mounting the clamping component on the movable seat and using a horizontally moving lead screw slide to drive the movable seat horizontally. The clamping component uses a U-shaped plate that cooperates with a movable locking block. The back of the locking block is connected to a self-locking adjustment component. By applying pressure through the self-locking adjustment component, the clamping surface on the front of the locking block clamps and fixes the tensile test piece, forming a self-locking clamping structure.
[0009] Preferably, the self-locking adjustment component includes a threaded rod that is threadedly connected to the end of the U-shaped plate. A pressure block is rotatably mounted on the inner end of the threaded rod. Two springs are mounted on the inner side of the pressure block. A wedge block is fixedly mounted between the inner ends of the two springs. An action slope is provided on the front of the wedge block, and a force-receiving slope is provided on the back of the locking block. The action slope can slide and engage with the force-receiving slope. The springs push the wedge block to move inward, and the action slope applies a force to the force-receiving slope, thereby pressing and locking the locking block against the tensile test piece.
[0010] In this self-locking adjustment component, the threaded rod is threadedly connected to the end of the U-shaped plate. Its position on the U-shaped plate can be changed by turning the threaded rod. The pressure block, spring, and wedge block at the inner end of the threaded rod are connected in sequence. When the threaded rod is turned, the pressure block pushes the spring to compress, and the spring transmits the force to the wedge block. The action slope on the outer side of the wedge block cooperates with the force-receiving slope on the back of the locking block. The spring's thrust is converted into a force that presses the locking block against the tensile test piece through the interaction of the action slope and the force-receiving slope, thus achieving the locking block's pressing and locking of the tensile test piece.
[0011] Preferably, the spring is a compression spring, and the preload of the spring is adjusted by screwing on a threaded rod.
[0012] This setting uses a compression spring. By turning the threaded rod, the relative position between the threaded rod and the U-shaped plate is changed, thereby compressing or releasing the spring and adjusting the spring's preload. The change in preload directly affects the magnitude of the wedge block's thrust on the locking block, thus achieving adjustment of the locking block's clamping force.
[0013] Preferably, a handle is fixedly installed at the outer end of the threaded rod.
[0014] This feature includes a handle installed at the end of the threaded rod furthest from the pressure block. The operator can rotate the threaded rod by holding and turning the handle, thereby adjusting the spring preload and controlling the clamping force of the locking block.
[0015] Preferably, the wedge block has a through guide hole in the middle, and the inner side walls of the U-shaped plate are provided with grooves. The pressure block, spring and wedge block are all located in the grooves. A guide rod is installed on the inner wall of the groove, and the outer end of the guide hole slides through the guide rod.
[0016] In this configuration, the guide rod guides the movement of the wedge block, restricting the wedge block to move only in a straight line along the direction of the guide rod, ensuring that the working slope of the wedge block always accurately matches the force-bearing slope of the locking block.
[0017] Preferably, the outer end of the front of the locking block is provided with an infeed ramp, which facilitates the smooth insertion of the tensile test piece and pushes the two locking blocks to the sides respectively, so as to realize the smooth entry of the tensile test piece into the clamping surface.
[0018] This setting features an inclined infeed surface on the outer front end of the locking block. When the tensile test piece is placed, it contacts the inclined infeed surface. As the tensile test piece is pushed in, the inclined infeed surface is compressed, forcing the locking block to move to both sides, creating space for the tensile test piece to enter the clamping surface. When the tensile test piece reaches the appropriate position, the locking block resets and clamps the tensile test piece under the action of the self-locking adjustment component.
[0019] Preferably, the clamping surface on the front of the locking block is provided with anti-slip texture.
[0020] This feature includes anti-slip textures on the clamping surface of the locking block. When the locking block clamps the tensile test piece, the anti-slip textures increase the surface roughness between the clamping surface and the tensile test piece. According to the friction formula, under constant pressure, an increase in surface roughness leads to an increase in friction, thereby effectively preventing the tensile test piece from sliding due to tension during the test.
[0021] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0022] In this self-locking tensile testing fixture, the self-locking adjustment mechanism is a key advantage in terms of clamping stability. The threaded rod is threadedly connected to the U-shaped plate; by turning the threaded rod, the position of the pressure block can be adjusted, thereby changing the spring preload. The spring pushes the wedge block, and the sliding interaction between the wedge block's inclined surface and the locking block's force-bearing inclined surface converts the spring's thrust into a clamping force on the locking block, achieving reliable locking of the tensile test specimen. This self-locking structure maintains stable clamping even when the tensile force approaches or reaches the specimen's ultimate bearing capacity during testing, preventing specimen loosening or detachment, ensuring smooth testing, and effectively improving the accuracy and reliability of test data.
[0023] In terms of specimen adaptability, this fixture also performs excellently. The inclined surface design at the outer end of the locking block in the clamping component allows tensile test specimens of different shapes and sizes to be smoothly pushed in and open the locking block, entering the clamping surface. The anti-slip texture on the front of the locking block further enhances the clamping ability for various specimens. Whether it is a high-hardness metal material or a low-hardness plastic or rubber product, it can be clamped stably, greatly improving the fixture's versatility for diverse specimens, reducing the tedious operation of frequently changing fixtures due to different specimens, and significantly improving testing efficiency.
[0024] In terms of ease of operation, the handle design at the outer end of the threaded rod allows operators to quickly tighten the threaded rod, adjust the spring preload, and thus control the clamping force of the locking block, making operation simple and labor-saving. The sliding fit between the guide hole in the middle of the wedge block and the guide rod on the inner wall of the U-shaped plate ensures the stability and accuracy of the wedge block during movement, making the adjustment operation smoother and reducing the difficulty and labor intensity of the operator. Attached Figure Description
[0025] Figure 1 This is a schematic diagram of the overall structure of this utility model;
[0026] Figure 2 This is a schematic diagram of the clamping component in this utility model;
[0027] Figure 3 This is a schematic diagram of the self-locking adjustment component in this utility model;
[0028] Figure 4 This is a schematic diagram of the locking block in this utility model;
[0029] The meanings of the labels in the diagram are as follows:
[0030] 1. Horizontal moving lead screw slide; 2. Moving seat; 3. Clamping component; 31. U-shaped plate; 311. Groove; 312. Guide rod; 32. Locking block; 321. Force-bearing inclined surface; 322. Feeding inclined surface; 4. Tensile test piece; 5. Self-locking adjustment component; 51. Threaded rod; 52. Pressure block; 53. Spring; 54. Wedge block; 541. Guide hole; 542. Acting inclined surface; 541. Guide hole; 55. Handle. Detailed Implementation
[0031] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0032] This utility model provides a self-locking tensile testing fixture, such as Figure 1 , Figure 2 As shown, the device includes a horizontally moving lead screw slide 1, a movable seat 2, and a clamping component 3. The clamping component 3 is mounted on one side of the movable seat 2. The movable seat 2 is driven to move horizontally by the horizontally moving lead screw slide 1. The clamping component 3 clamps and fixes the tensile test piece 4 by self-locking. The clamping component 3 encloses a U-shaped plate 31. Two symmetrical locking blocks 32 are movably arranged inside the opening of the U-shaped plate 31. The back of the locking blocks 32 is adjusted and pressure is applied by a self-locking adjustment component 5, thereby clamping and fixing the tensile test piece 4 through the clamping surface of the front of the locking blocks 32. Among them, the horizontally moving lead screw slide 1 is a driving structure with a lead screw and a slider threadedly connected, and the movable seat 2 is fixedly connected to the slider.
[0033] In use, the clamping component 3 is mounted on the movable base 2, and the movable base 2 is driven to move horizontally by the horizontal moving screw slide 1, thus flexibly adjusting the position of the tensile test piece 4. The clamping component 3 uses a U-shaped plate 31 to cooperate with the movable locking block 32. The back of the locking block 32 is connected to the self-locking adjustment component 5. By applying pressure through the self-locking adjustment component 5, the clamping surfaces on the front of the two locking blocks 32 clamp and fix the tensile test piece 4, forming a self-locking clamping structure. The combination of the horizontal moving screw slide 1 and the movable base 2 facilitates the adjustment of the position of the clamping component 3 to adapt to tensile test pieces 4 of different lengths and testing requirements. The self-locking clamping structure ensures that the tensile test piece 4 is stably clamped during the test, avoiding test errors caused by loosening and improving the accuracy and reliability of the test. At the same time, the overall structure is simple and easy to install and operate.
[0034] In this embodiment, as Figure 3As shown, the self-locking adjustment component 5 includes a threaded rod 51, which is threadedly connected to the end of the U-shaped plate 31. A pressure block 52 is rotatably mounted on the inner end of the threaded rod 51. Two springs 53 are mounted on the inner side of the pressure block 52. A wedge block 54 is fixedly mounted between the inner ends of the two springs 53. An action slope 542 is provided on the front of the wedge block 54, and a force-receiving slope 321 is provided on the back of the locking block 32. The action slope 542 can slide and engage with the force-receiving slope 321. The springs 53 push the wedge block 54 to move inward, and the action slope 542 applies a force to the force-receiving slope 321, thereby locking the locking block 32 against the tensile test piece 4.
[0035] In use, in the self-locking adjustment component 5, the threaded rod 51 is threadedly connected to the end of the U-shaped plate 31. By turning the threaded rod 51, its position on the U-shaped plate 31 can be changed. The pressure block 52, spring 53 and wedge block 54 at the inner end of the threaded rod 51 are connected in sequence. When the threaded rod 51 is turned, the pressure block 52 pushes the spring 53 to compress, and the spring 53 transmits the force to the wedge block 54. The action slope 542 on the front of the wedge block 54 cooperates with the force-receiving slope 321 on the back of the locking block 32. The thrust of the spring 53 is converted into a force that presses the locking block 32 against the tensile test piece 4 through the interaction of the action slope 542 and the force-receiving slope 321, thereby realizing the locking block 32 pressing and locking the tensile test piece 4. By utilizing the threaded drive and the inclined plane principle of the wedge block 54, the clamping force of the locking block 32 can be precisely adjusted. The spring 53 acts as a buffer and stabilizes the pressure, making the clamping force more uniform and stable, ensuring that the tensile test piece 4 is reliably clamped throughout the test, effectively preventing the sample from loosening or falling off, and improving the stability and accuracy of the test. At the same time, the self-locking function of this structure can prevent the clamping force from weakening due to vibration and other factors during the tensile test, ensuring the safe and smooth conduct of the test.
[0036] Specifically, spring 53 is a compression spring, and its preload is adjusted by screwing on the threaded rod 51. Spring 53 is a compression spring; by screwing on the threaded rod 51, the relative position of the threaded rod 51 and the U-shaped plate 31 is changed, thereby compressing or releasing spring 53 and adjusting its preload. The change in preload directly affects the pushing force of the wedge block 54 on the locking block 32, thus adjusting the clamping force of the locking block 32. Operators can flexibly adjust the preload of spring 53 according to the material, shape, and size of different tensile test specimens 4 to adapt to different clamping requirements. For specimens with higher hardness or thicker thickness, the preload of spring 53 can be increased to ensure secure clamping; for specimens with lower hardness or thinner thickness, the preload can be reduced to prevent damage to the specimen due to excessive clamping force. This effectively improves the adaptability and versatility of the fixture for different specimens and expands its application range.
[0037] Furthermore, a handle 55 is fixedly installed on the outer end of the threaded rod 51 away from the pressure block 52. The operator grips and rotates the handle 55, causing the threaded rod 51 to rotate, thereby adjusting the preload of the spring 53 and controlling the clamping force of the locking block 32. The handle 55 greatly facilitates the operator's operation of the threaded rod 51. Compared to directly screwing the threaded rod 51, using the handle 55 allows for easier and more convenient adjustment of the clamping force. At the same time, the handle 55 increases the contact area between the operator's hand and the threaded rod 51, making the operation more stable and precise, reducing the difficulty of operation, and improving the efficiency of the test operation.
[0038] Furthermore, a through guide hole 541 is provided in the middle of the wedge block 54, and grooves 311 are provided on both sides of the inner side of the U-shaped plate 31. The pressure block 52, spring 53 and wedge block 54 are all located in the grooves 311. A guide rod 312 is installed on the inner wall of the groove 311, and the outer end of the guide hole 541 slides through the guide rod 312.
[0039] When the threaded rod 51 is tightened to adjust the clamping force, the guide rod 312 provides guidance for the movement of the wedge block 54, restricting the wedge block 54 to move only in a straight line along the direction of the guide rod 312. This ensures that the action slope 542 of the wedge block 54 always accurately matches the force-bearing slope 321 of the locking block 32. The guiding structure ensures the stability and accuracy of the wedge block 54 during movement, preventing the wedge block 54 from shifting or wobbling. It ensures that the thrust of the spring 53 can be accurately and effectively transmitted to the locking block 32, making the locking block 32 evenly stressed and improving the stability and reliability of the clamping force. At the same time, the stable guide also reduces wear between components, extends the service life of the fixture, and reduces operating costs.
[0040] Furthermore, such as Figure 4 As shown, the outer end of the front of the locking block 32 is provided with an infeed inclined surface 322. The infeed inclined surface 322 facilitates the smooth pushing of the tensile test piece 4 and pushes the two locking blocks 32 to the sides respectively, so as to realize the smooth entry of the tensile test piece 4 into the clamping surface.
[0041] The inclined surface 322 at the outer end of the locking block 32 allows the tensile test specimen 4 to contact the inclined surface 322 during placement. As the tensile test specimen 4 is pushed in, the inclined surface 322 is compressed, forcing the two locking blocks 32 to move to both sides, creating space for the tensile test specimen 4 to enter the clamping surface. When the tensile test specimen 4 reaches the appropriate position, the locking block 32 resets and clamps the tensile test specimen 4 under the action of the self-locking adjustment component 5. The design of the inclined surface 322 makes the installation process of the tensile test specimen 4 smoother and more convenient. Operators can quickly place the specimen into the clamping surface without having to adjust its position. At the same time, this design effectively improves the compatibility of the fixture with specimens of different shapes. Even if the specimen edges are irregular, it can still smoothly enter the clamping area through the inclined surface 322, further enhancing the practicality and versatility of the fixture, saving test preparation time, and improving work efficiency.
[0042] Furthermore, the clamping surface on the front of the locking block 32 is provided with anti-slip texture. The anti-slip texture increases the friction between the anti-slip texture and the tensile test piece 4, preventing the tensile test piece 4 from sliding during the test.
[0043] Anti-slip textures are provided on the clamping surface of the locking block 32. When the locking block 32 clamps the tensile test specimen 4, the anti-slip textures increase the surface roughness between the clamping surface and the tensile test specimen 4. According to the friction formula, under constant pressure, increased surface roughness leads to increased friction, thus effectively preventing the tensile test specimen 4 from slipping due to tension during the test. The anti-slip textures significantly improve the clamping effect of the fixture on the tensile test specimen 4, ensuring the specimen remains stable throughout the test and avoiding inaccurate test data or test failure due to slippage. Whether it is a smooth metal specimen or a specimen made of other materials with special surface texture, the anti-slip textures can effectively enhance the clamping force, improve the reliability and accuracy of the test, and ensure the smooth conduct of the tensile test.
[0044] In use of this self-locking tensile testing fixture, before conducting the tensile test, the operator aligns the tensile test piece 4 with the infeed ramp 322 at the outer end of the locking block 32. As the tensile test piece 4 is pushed in, the infeed ramp 322 is compressed, forcing the two locking blocks 32 to move to both sides, thus creating space for the tensile test piece 4 to enter the clamping surface. At this point, the operator can easily place the tensile test piece 4 in the appropriate position.
[0045] After the tensile test piece 4 is placed in place, the operator begins to adjust the self-locking adjustment component 5. Holding and rotating the handle 55 at the outer end of the threaded rod 51, the threaded rod 51, being threaded to the end of the U-shaped plate 31, causes the threaded rod 51 to move on the U-shaped plate 31. This movement of the threaded rod 51 moves the pressure block 52 inwards, compressing the compression spring 53. The thrust generated by the spring 53 is transmitted to the wedge block 54. The guide hole 541 in the middle of the wedge block 54 slides against the guide rod 312 on the inner wall of the U-shaped plate 31, ensuring stable movement of the wedge block 54 along a straight line. The inclined surface 542 on the outer side of the wedge block 54 interacts with the force-receiving inclined surface 321 on the back of the locking block 32. The thrust of the spring 53, through the action of these two inclined surfaces, is converted into a force that presses the locking block 32 against the tensile test piece 4. As the threaded rod 51 is continuously screwed on, the preload of the spring 53 increases, and the clamping force of the locking block 32 on the tensile test specimen 4 also increases accordingly. The operator can flexibly adjust the preload of the spring 53 according to the material, shape and size of the tensile test specimen 4 to ensure that different specimens can be firmly and appropriately clamped.
[0046] After clamping and fixing, the movable seat 2 moves horizontally under the drive of the horizontal moving screw slide 1, adjusting the tensile test piece 4 to a suitable test position. During the tensile test, the tensile force is gradually applied to the tensile test piece 4. Due to the self-locking structure formed by the self-locking adjustment component 5, even under large tensile forces, the locking block 32 can maintain stable clamping of the tensile test piece 4. The spring 53 plays a role in buffering and stabilizing the pressure, ensuring uniform and stable clamping force, and preventing the clamping force from weakening or the sample from loosening due to vibration or other factors. Throughout the test, the fixture, with its stable clamping performance and precise adjustment function, ensures the accuracy and reliability of the tensile test until the tensile test piece 4 reaches its bearing limit, completing the entire tensile test.
[0047] After the test, turn the handle 55 in the opposite direction. The threaded rod 51 drives the pressure block 52 to restore the deformation of the spring 53. The pressure of the wedge block 54 on the locking block 32 is reduced, and the operator can easily take out the tensile test piece 4 to prepare for the next test.
[0048] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.
Claims
1. A self-locking tension test fixture comprising a horizontal moving screw slide (1), a moving seat (2) and a clamping component (3), characterized in that: The clamping component (3) is installed on one side of the movable seat (2). The movable seat (2) is driven to move horizontally by the horizontal moving screw slide (1). The clamping component (3) clamps and fixes the tensile test piece (4) by self-locking. The clamping component (3) covers a U-shaped plate (31). Two symmetrical locking blocks (32) are movably arranged inside the opening of the U-shaped plate (31). The back of the locking block (32) is adjusted and pressure is applied by the self-locking adjustment component (5). Then, the clamping surface of the front of the locking block (32) clamps and fixes the tensile test piece (4).
2. The self-locking tension test fixture of claim 1, wherein: The self-locking adjustment component (5) includes a threaded rod (51), which is threaded to the end of the U-shaped plate (31). A pressure block (52) is rotatably installed on the inner end of the threaded rod (51). Two springs (53) are installed on the inner side of the pressure block (52). A wedge block (54) is fixedly installed between the inner ends of the two springs (53). An action slope (542) is provided on the front of the wedge block (54), and a force-bearing slope (321) is provided on the back of the locking block (32). The action slope (542) can slide and engage with the force-bearing slope (321). The springs (53) push the wedge block (54) to move inward, and the action slope (542) applies force to the force-bearing slope (321), thereby locking the locking block (32) against the tensile test piece (4).
3. The self-locking tension test fixture of claim 2, wherein: The spring (53) is a compression spring, and the preload of the spring (53) is adjusted by screwing the threaded rod (51).
4. The self-locking tension test fixture of claim 2, wherein: A handle (55) is fixedly installed at the outer end of the threaded rod (51).
5. The self-locking tension test fixture of claim 2, wherein: The wedge block (54) has a through guide hole (541) in the middle. The inner side of the U-shaped plate (31) has grooves (311) on both sides. The pressure block (52), spring (53) and wedge block (54) are all located in the grooves (311). The inner wall of the groove (311) is equipped with a guide rod (312). The outer end of the guide hole (541) slides through the guide rod (312).
6. The self-locking tension test fixture of claim 1, wherein: The outer end of the front of the locking block (32) is provided with an infeed slope (322). The infeed slope (322) facilitates the smooth insertion of the tensile test piece (4) and pushes the two locking blocks (32) to the sides respectively, so as to realize the smooth entry of the tensile test piece (4) into the clamping surface.
7. The self-locking tension test fixture of claim 1, wherein: The clamping surface on the front of the locking block (32) is provided with anti-slip texture.