An experimental extensometer
By employing a bidirectional screw-driven synchronous reverse motion and a rack and pinion meshing design in the extensometer, the transmission instability caused by screw tooth retraction was solved, achieving higher measurement accuracy and experimental precision.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- RUGAO ENG QUALITY INSPECTION CENT CO LTD
- Filing Date
- 2025-07-30
- Publication Date
- 2026-07-07
AI Technical Summary
When excessive tension is applied, the force between the screw and the clamping mechanism of the existing experimental extensometer increases sharply, which can easily lead to tooth stripping, affecting the transmission accuracy and the stability of the stretching process, resulting in measurement errors.
The design employs a bidirectional screw-driven, synchronously reversible moving clamping plate and rack plate meshing with a unidirectional rotating gear. The driving component restricts the moving clamping plate from approaching, and the combination of clamping teeth increases friction and circular block support guide ensures the stability and accuracy of the stretching process.
It effectively alleviated the problem of screw tooth delamination, improved the stability and measurement accuracy of the stretching process, reduced experimental errors, and ensured the accuracy of experimental results.
Smart Images
Figure CN224471420U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of extensometer technology, and in particular to an experimental extensometer. Background Technology
[0002] In the field of materials science and engineering, the tensile properties of elastic materials are one of the key indicators for evaluating their quality and suitability, and tensile testing is an important means of obtaining these performance parameters. In tensile testing, the extensometer plays an indispensable role, as it can accurately measure the amount of deformation of the material during tensile stress, providing fundamental data for calculating important mechanical properties such as the elastic modulus and yield strength of the material.
[0003] In existing technologies, some experimental extensometers employ a bidirectional screw-driven tensile method. A drive device rotates the screw, causing relative motion in the clamping mechanism that cooperates with the screw, thus achieving tensile testing of the elastic material specimen. The initial intention behind the bidirectional screw drive design was to ensure the symmetry of the tensile force on the specimen during the tensile process.
[0004] Regarding the aforementioned technologies, the inventors believe that when the applied tension is too large during the experiment, the force between the screw and the clamping mechanism will increase sharply, easily leading to tooth stripping of the screw. Tooth stripping not only affects the accuracy of the transmission but also disrupts the stability of the stretching process, thereby causing errors in the deformation measured by the extensometer. Utility Model Content
[0005] The purpose of this application is to provide an extensometer for experiments to improve the problem that when the applied tension is too large in the experiment, the force between the screw and the clamping mechanism will increase sharply, which will easily lead to the screw teeth deteriorating.
[0006] This application provides an extensometer for laboratory use, employing the following technical solution:
[0007] An experimental extensometer includes a base plate with a vertical plate arranged vertically. A bidirectional screw is rotatably mounted on the vertical plate along its length. A driving component is located at one end of the bidirectional screw on the vertical plate. The bidirectional screw is threadedly connected to two synchronously moving clamping plates that move in opposite directions. The moving clamping plates are slidably engaged with the vertical plate. Each moving clamping plate is equipped with a clamping assembly for holding elastic material. The clamping assembly includes a fixed block fixed to the moving clamping plate and a moving block slidably mounted to the fixed block. The moving block is equipped with a threaded rod threadedly connected to the fixed block, and the threaded rod is threadedly connected to an adjusting nut. A rack plate is located on one side of the base plate near the vertical plate. A driving component connected to the rack plate is located on the side of the base plate opposite to the vertical plate. A unidirectional rotating gear that meshes with the rack plate is rotatably mounted on the side of the moving clamping plate closest to the rack plate.
[0008] By adopting the above technical solution, the bidirectional screw drives the moving clamps to move synchronously in opposite directions under the action of the first driving component, thereby stretching the elastic material and ensuring the symmetry of the tensile force. The rack plate is driven by the second driving component and meshes with the unidirectional rotating gear, which can limit the moving clamps from getting close to each other during stretching. This effectively alleviates the problem of screw tooth derailment when the tensile force is too large in the prior art, enhances the stability of the stretching process, and improves the measurement accuracy.
[0009] Optionally, clamping teeth are provided on the side of the fixed block and the moving block that are close to each other.
[0010] By adopting the above technical solution, when the clamping component fixes the elastic material, the clamping teeth can increase the friction between the clamping teeth and the material, reduce the slippage of the elastic material during the stretching process, and further ensure the accuracy of the experimental results.
[0011] Optionally, the vertical plate is provided with graduations along its length.
[0012] By adopting the above technical solution, during the process of stretching the material by moving the clamping plates, the operator can intuitively read the change in distance between the two moving clamping plates through the scale, quickly obtain the amount of material deformation, and simplify the experimental operation process.
[0013] Optionally, a guide rod is provided through the rack plate on the side of the vertical plate closest to the rack plate.
[0014] By adopting the above technical solution, when the second driving component pushes the rack plate to move, the guide rod can guide the movement of the rack plate, reduce the shaking of the rack plate during the movement, and help ensure the stability of the meshing between the rack plate and the one-way rotating gear.
[0015] Optionally, a limiting plate is provided at the end of the guide rod away from the vertical plate.
[0016] By adopting the above technical solution, the limiting plate can effectively prevent the rack plate from moving excessively under the action of the second driving component and detaching from the guide rod, thus avoiding equipment failure caused by the rack plate detaching.
[0017] Optionally, the vertical plate is provided with a sliding groove along its length, and the movable clamping plate is provided with a slider that slides and engages with the sliding groove.
[0018] By adopting the above technical solution, the cooperation between the slider and the groove guides and limits the movement of the moving clamp, ensuring that the moving clamp can only move in a straight line along the length of the vertical plate under the drive of the bidirectional screw. This helps to prevent the moving clamp from deviating, ensures the accuracy of the stretching direction, and reduces experimental errors.
[0019] Optionally, the movable clamp is provided with a circular block, the peripheral sidewall of which is in contact with an elastic material.
[0020] By adopting the above technical solution, the circular block adheres to the elastic material, which can support and guide the material during the stretching process, reduce the displacement or shaking caused by uneven force on the material, and enable the material to deform stably along the preset stretching direction, thereby further improving the stability of the stretching process.
[0021] Optionally, the circumference of the circular block's peripheral sidewall is provided with a corner groove.
[0022] By adopting the above technical solution, the corner groove helps to stabilize the elastic material and reduce the wobbling of the elastic material on the round block.
[0023] In summary, this application includes at least one of the following beneficial technical effects of an experimental extensometer:
[0024] 1. Under the action of the first driving component, the bidirectional screw drives the moving clamping plate to move synchronously in opposite directions, thereby stretching the elastic material and ensuring the symmetry of the tensile force. The rack plate is driven by the second driving component and meshes with the unidirectional rotating gear, which can limit the moving clamping plates from getting close to each other during stretching. This effectively alleviates the problem of screw tooth derailment when the tensile force is too large in the prior art, enhances the stability of the stretching process, and improves the measurement accuracy.
[0025] 2. When the clamping assembly fixes the elastic material, the clamping teeth can increase the friction between the clamping teeth and the material, reduce the slippage of the elastic material during the stretching process, and further ensure the accuracy of the experimental results;
[0026] 3. The round blocks fit into the elastic material, which can support and guide the material during the stretching process, reducing the offset or shaking caused by uneven force on the material, and enabling the material to deform stably along the preset stretching direction, further improving the stability of the stretching process. Attached Figure Description
[0027] Figure 1 This is a schematic diagram illustrating the bidirectional screw structure in the embodiment;
[0028] Figure 2 This is a schematic diagram of the overall structure of the experimental extensometer;
[0029] Figure 3 yes Figure 2 An enlarged schematic diagram of the structure at point A in the middle.
[0030] In the diagram, 1. Base plate; 2. Vertical plate; 21. Slide groove; 3. Bidirectional screw; 31. Drive component one; 4. Moving clamping plate; 41. Slider; 5. Clamping assembly; 51. Fixed block; 52. Moving block; 521. Threaded rod; 522. Adjusting nut; 53. Clamping teeth; 6. Rack plate; 61. Drive component two; 7. One-way rotating gear; 8. Scale; 9. Guide rod; 91. Limiting plate; 10. Round block; 101. Corner groove. Detailed Implementation
[0031] The following is in conjunction with the appendix Figure 1 -Appendix Figure 3 This application will be described in further detail below.
[0032] An experimental extensometer, with reference to Figure 1 The system includes a base plate 1, on which a vertical plate 2 is fixedly mounted by welding along the vertical direction. A bidirectional screw 3 is rotatably mounted on the vertical plate 2 along its length direction via bearings. The bidirectional screw 3 has two sections of threads in opposite directions. A drive component 31 is fixedly mounted on one end of the vertical plate 2 via bolts. The drive component 31 is a servo motor that can rotate in both directions, and the output shaft of the drive component 31 is fixedly connected to the end of the bidirectional screw 3 via a coupling.
[0033] Reference Figure 2 The bidirectional screw 3 is threadedly connected to two synchronously moving clamping plates 4. The moving clamping plates 4 are slidably engaged with the vertical plate 2. The vertical plate 2 is integrally formed with a scale 8 along its length. The vertical plate 2 is provided with a sliding groove 21 along its length. The moving clamping plate 4 is integrally formed with a slider 41 that is slidably engaged with the sliding groove 21. The cross-sections of both the slider 41 and the sliding groove 21 are T-shaped, so as to achieve sliding engagement and prevent the moving clamping plate 4 from detaching from the vertical plate 2.
[0034] Reference Figure 2 , Figure 3 The movable clamping plate 4 is fixed with a clamping assembly 5 for clamping elastic material by bolts. The clamping assembly 5 includes a fixed block 51 fixed to the movable clamping plate 4 by bolts and a movable block 52 slidably disposed with the fixed block 51. Specifically, the movable block 52 is welded with a threaded rod 521 that is threadedly connected to the fixed block 51. The fixed block 51 has a threaded hole for the threaded rod 521 to pass through. The threaded rod 521 is threadedly connected with an adjusting nut 522. The fixed block 51 and the movable block 52 are both integrally formed with clamping teeth 53 on the side close to each other. The clamping teeth 53 are serrated and used to enhance the clamping force on the elastic material.
[0035] Reference Figure 2 The movable clamping plate 4 is fixed with a round block 10 by bolts. The side wall of the round block 10 is in contact with the elastic material. The side wall of the round block 10 is uniformly provided with corner grooves 101 in the circumferential direction. The corner grooves 101 are V-shaped and can restrict the elastic material to be located in the corner grooves 101.
[0036] Reference Figure 2A rack plate 6 is provided on one side of the base plate 1 and the rack plate 2. A second driving component 61 connected to the rack plate 6 is fixed to the side of the base plate 1 opposite to the rack plate 2 by bolts. The piston rod end of the second driving component 61 is fixed to the rack plate 6 by bolts. The second driving component 61 is a cylinder. A one-way rotating gear 7 that can mesh with the rack plate 6 is provided on the side of the movable clamping plate 4 near the rack plate 6 by bearings. The one-way rotating gear 7 is provided with a ratchet and pawl structure, which restricts it to rotate only in one direction. The one-way rotating gear 7 restricts the movable clamping plates 4 from getting close to each other when stretching the elastic material.
[0037] Reference Figure 2 A guide rod 9 is provided through the rack plate 6 on the side of the vertical plate 2 near the rack plate 6. The rack plate 6 has a guide hole for the guide rod 9 to pass through. A limit plate 91 is fixed to the end of the guide rod 9 away from the vertical plate 2 by bolts. The diameter of the limit plate 91 is larger than the diameter of the guide hole to prevent the rack plate 6 from detaching from the guide rod 9.
[0038] The implementation principle of this application embodiment is as follows:
[0039] In actual use, the elastic material is first placed between the clamping components 5 of the two movable clamping plates 4. The movable block 52 is brought closer to the fixed block 51 by rotating the adjusting nut 522. The clamping teeth 53 engage the elastic material and the adjusting nut 522 is tightened to fix it. At this time, the side wall of the circular block 10 is in contact with the elastic material. After the experiment is started, the second driving component 61 pushes the rack plate 6 to move along the guide rod 9, which drives the unidirectional rotating gear 7 that meshes with it to rotate, restricting the movable clamping plates 4 from getting close to each other during stretching and enhancing stability. The first driving component 31 drives the bidirectional screw 3 to rotate, so that the movable clamping plates 4 that are slidably engaged with the slide groove 21 of the vertical plate 2 move synchronously in the opposite direction to apply the initial tensile force. The distance change can be read on the scale 8 of the vertical plate 2. During the whole process, if the force is too large and the bidirectional screw 3 has a tendency to retract its teeth, the meshing of the unidirectional rotating gear 7 and the rack plate 6 will restrict the reverse movement of the movable clamping plates 4, alleviating the problem of decreased transmission accuracy and shaking.
[0040] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be included within the scope of protection of this application.
Claims
1. An extensometer for experimental use, comprising a base plate (1), characterized in that: The base plate (1) is provided with a vertical plate (2) in the vertical direction. The vertical plate (2) is rotatably provided with a bidirectional screw (3) in the length direction. The vertical plate (2) is provided with a driving component (31) at one end of the bidirectional screw (3). The bidirectional screw (3) is threadedly connected to two synchronously moving clamping plates (4). The moving clamping plates (4) are slidably engaged with the vertical plate (2). The moving clamping plates (4) are provided with a clamping assembly (5) for clamping elastic material. The clamping assembly (5) includes a fixing block (51) fixed to the moving clamping plate (4) and a fixing block (51) fixed to the fixing block (51). The sliding block (52) is provided with a threaded rod (521) that is threadedly connected to the fixed block (51), and the threaded rod (521) is threadedly connected to an adjusting nut (522); the base plate (1) is provided with a rack plate (6) on one side of the vertical plate (2), and the base plate (1) is provided with a driving component (61) connected to the rack plate (6) on the side of the rack plate (6) away from the vertical plate (2); the movable clamping plate (4) is rotatably provided with a one-way rotating gear (7) that can mesh with the rack plate (6) on the side close to the rack plate (6).
2. The experimental extensometer according to claim 1, characterized in that: Clamping teeth (53) are provided on the side of the fixed block (51) and the moving block (52) that are close to each other.
3. The experimental extensometer according to claim 1, characterized in that: The vertical plate (2) is provided with graduations (8) along its length.
4. The experimental extensometer according to claim 3, characterized in that: A guide rod (9) is provided on the side of the vertical plate (2) near the rack plate (6) that passes through the rack plate (6).
5. The experimental extensometer according to claim 4, characterized in that: A limit plate (91) is provided at the end of the guide rod (9) away from the vertical plate (2).
6. The experimental extensometer according to claim 4, characterized in that: The vertical plate (2) is provided with a sliding groove (21) along its length direction, and the movable clamping plate (4) is provided with a slider (41) that slides and engages with the sliding groove (21).
7. The experimental extensometer according to claim 1, characterized in that: The movable clamp (4) is provided with a circular block (10), and the peripheral sidewall of the circular block (10) is in contact with an elastic material.
8. The experimental extensometer according to claim 7, characterized in that: The circular block (10) has a corner groove (101) on its circumferential sidewall.