A bending test fixture

Abstract

The utility model relates to the technical field of bending experiment equipment, concretely relates to a bending experiment test frock, including base and the support of setting at the two sides of base top front and back, be provided with adjusting assembly between two supports, be provided with the central shaft of moving along vertical direction on adjusting assembly, and the central shaft is pressed on the upper surface of sample piece, the support is hingedly provided with the bearing assembly, and the bearing assembly includes the bending seat of setting up symmetrically at the left and right sides of support, and one end of two bending seats all is hingedly connected with the support, and the other end of bending seat is equipped with the oil cylinder, the utility model discloses bearing assembly cooperation central axle, form the two -way clamping of up and down to sample piece, effectively prevent sample piece from moving or deviating in the testing process, and the oil cylinder telescopic drive bending seat swing when using, realize the bending loading of sample piece, and adopt two symmetric oil cylinders and drive the swing of left and right sides bending seat respectively, and the problem of eccentric load caused by traditional single -sided loading is avoided in the bilateral synchronous loading mode.

Description

Technical Field

[0001] This utility model relates to the field of bending test equipment technology, specifically to a bending test fixture. Background Technology

[0002] Bending tests are a method for evaluating a material's resistance to bending under bending loads. By conducting bending tests, the bending conditions that a material might encounter in real-world applications can be simulated, thereby assessing its physical durability and insulation properties under bending conditions. During a bending test, a certain bending stress is typically applied, and then the material is observed to determine whether it fails and the strength at failure. This testing method can be used for various materials, such as metals, plastics, fiber-reinforced plastics, and ceramics.

[0003] Traditional bending test devices typically use a manual turntable to apply bending force. Although the structure is simple and the cost is low, there are many shortcomings in practical applications: 1. The specimen is not firmly fixed: the traditional tooling fixture design is not reasonable enough, making it difficult to achieve stable clamping of the specimen. It is easy for the specimen to move or shift during the test, affecting the accuracy of the test results; 2. Uneven loading: the unilateral loading method is prone to uneven force on the specimen, resulting in large deviations in the test data. Summary of the Invention

[0004] To address the problems of unstable specimen fixation and uneven loading in traditional bending testing devices, this invention proposes a bending test fixture. The fixture supports the lower surface of the specimen through a load-bearing component, while the upper central shaft presses against the upper surface, achieving bidirectional clamping. This design effectively prevents the specimen from moving or shifting during testing, significantly improving test stability and repeatability. Furthermore, two symmetrically arranged hydraulic cylinders drive the bending seats on the left and right sides to swing, and the dual-sided synchronous loading method avoids the off-center loading problem caused by traditional single-sided loading.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows: A bending test fixture includes a base and supports positioned on the front and rear sides above the base. An adjustment assembly is provided between the two supports, and a central shaft that moves vertically is mounted on the adjustment assembly, pressing against the upper surface of a sample. A load-bearing assembly is hinged to the supports, and the load-bearing assembly includes bending seats symmetrically arranged on the left and right sides of the supports. One end of each bending seat is hinged to the support, and a hydraulic cylinder is mounted on the other end of the bending seat. The load-bearing assembly provides support to the lower surface of the sample, while simultaneously coordinating with the pressing action of the central shaft on the upper surface of the sample to achieve bidirectional clamping. Two symmetrically arranged hydraulic cylinders drive the bending seats on the left and right sides to swing.

[0006] Furthermore, the adjustment assembly includes a horizontal plate and a mounting plate. A lead screw is disposed below the horizontal plate, with both ends of the lead screw rotatably mounted on a bracket. The lead screw has a positive thread section and a negative thread section, and threaded blocks are respectively disposed on the positive thread section and the negative thread section. A connecting rod is hinged to each of the two threaded blocks. The mounting plate is an n-shaped plate, with both ends of the central shaft rotatably mounted on the n-shaped plate. A lug is disposed on the top of the mounting plate, and the lower ends of the connecting rods are hinged to the lugs. By rotating the lead screw clockwise or counterclockwise, the two threaded blocks can move synchronously inward or outward. The threaded blocks are hinged to an inclined connecting rod. When the threaded blocks move horizontally along the lead screw, on the one hand, the two threaded blocks move synchronously inward, the connecting rod pushes the mounting plate downward, and on the other hand, the two threaded blocks move synchronously outward, the connecting rod pulls the central shaft upward, thereby realizing the vertical movement of the central shaft and pressing the central shaft against the upper surface of the sample.

[0007] Furthermore, a slide rail is provided at the bottom of the horizontal plate, and a slider that cooperates with the slide rail is provided on the threaded block. The slider moves along the slide rail to achieve lateral movement, ensuring synchronization. More importantly, the slide rail bears the lateral force, preventing the lead screw from deforming under radial load.

[0008] Furthermore, the load-bearing component also includes a support shaft, which is disposed between the two supports and located below the central shaft. The bending seat is rotatably connected to the support shaft via a support. This structure enables the bending seat to swing flexibly.

[0009] Furthermore, the telescopic rod of the hydraulic cylinder is hinged to the bending seat via an upper connecting plate, and the cylinder body is hinged to the base via a lower connecting plate. The extension and retraction of the hydraulic cylinder drives the bending seat to swing, thereby achieving bending loading on the sample.

[0010] Furthermore, each of the bending seats is provided with a support assembly, which includes two bearing seats and driven rollers disposed between the two bearing seats. The two driven rollers press against the lower surface of the sample. The driven rollers pressing against the lower surface of the sample form a support point.

[0011] Furthermore, a handle is fixedly installed at one end of the lead screw after passing through the bracket. By rotating the handle, the lead screw can be rotated clockwise or counterclockwise, thereby adjusting the vertical position of the central shaft. The beneficial effects of this utility model through the above technical solution are as follows: 1. The bending test fixture provided by this utility model allows for the following steps: Before use, the sample is passed through the support shaft and placed stably on the two driven rollers. Then, the handle is turned clockwise, causing the two threaded blocks to move inward synchronously, driving the connecting rod to push the mounting plate downward, thereby moving the central axis downward until it presses against the upper surface of the sample, thus fixing the sample. During testing, the lifting and lowering of the two hydraulic cylinders is synchronously controlled by an external controller. The extension and retraction of the hydraulic cylinders drive the bending seat to swing, thereby applying a bending load to the sample to observe whether the material is damaged and the strength at the time of damage, thus evaluating the material's bending resistance under bending load. After the test, the handle is turned counterclockwise, causing the two threaded blocks to move outward synchronously, driving the connecting rod to pull the mounting plate upward, thereby moving the central axis upward and separating it from the sample, making it easy to remove the sample and completing the entire test process.

[0012] 2. The key improvement of this utility model is that the support shaft in the bearing component, together with the central shaft above, forms a two-way clamping on the sample, which effectively prevents the sample from moving or shifting during the test, and improves the stability and repeatability of the test. When in use, the hydraulic cylinder extends and retracts to drive the bending seat to swing, thereby achieving bending loading on the sample. Furthermore, two symmetrically arranged hydraulic cylinders drive the bending seats on the left and right sides to swing respectively. The dual-side synchronous loading method avoids the off-center loading problem caused by the traditional single-side loading. Attached Figure Description

[0013] Figure 1 This is a perspective view of a bending test fixture according to the present invention; Figure 2 This is a schematic diagram of the adjustment component in a bending test fixture of this utility model; Figure 3 This is a schematic diagram of the load-bearing component in a bending test fixture of this utility model; Figure 4 This is a schematic diagram illustrating the application state of a bending test fixture according to this utility model.

[0014] The numbers in the attached diagram are: 1. Base; 2. Bracket; 3. Central shaft; 4. Bending seat; 5. Hydraulic cylinder; 6. Horizontal plate; 7. Mounting plate; 8. Lead screw; 9. Threaded block; 10. Connecting rod; 11. Ear seat; 12. Slide rail; 13. Slider; 14. Support shaft; 15. Support; 16. Upper connecting plate; 17. Bearing seat; 18. Driven roller; 19. Handle; 20. Sample piece. Detailed Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings and specific embodiments: like Figures 1-4As shown, this embodiment provides a bending test fixture, including a base 1 and supports 2 arranged on the front and rear sides above the base 1. An adjustment assembly is provided between the two supports 2, and a central shaft 3 that moves vertically is provided on the adjustment assembly. The central shaft 3 presses against the upper surface of the specimen 20. A bearing assembly is hinged to the support 2, and the bearing assembly includes bending seats 4 symmetrically arranged on the left and right sides of the support 2. One end of each bending seat 4 is hinged to the support 2, and a hydraulic cylinder 5 is installed at the other end of the bending seat 4. This utility model provides support to the lower surface of the specimen 20 by setting the bearing assembly, and at the same time, the central shaft 3 above presses against the upper surface of the specimen 20, realizing bidirectional clamping. This design effectively prevents the specimen 20 from moving or shifting during the test, significantly improving the stability and repeatability of the test. Furthermore, the use of two symmetrically arranged hydraulic cylinders 5 to drive the bending seats 4 on the left and right sides to swing, and the dual-sided synchronous loading method avoids the off-center loading problem caused by traditional single-sided loading.

[0016] In this example, the adjustment assembly includes a horizontal plate 6 and a mounting plate 7. A lead screw 8 is provided below the horizontal plate 6. The two ends of the lead screw 8 are rotatably mounted on the bracket 2. The lead screw 8 is provided with a positive thread section and a negative thread section. Threaded blocks 9 are respectively provided on the positive thread section and the negative thread section of the lead screw 8. Connecting rods 10 are hinged to both of the threaded blocks 9. The mounting plate 7 is an n-shaped plate. The two ends of the central shaft 3 are rotatably mounted on the n-shaped plate. Ear seats 11 are provided on the top of the mounting plate 7. The lower ends of the connecting rods 10 are all hinged to the ear seats 11.

[0017] Please refer to this again. Figure 2 In the adjusting assembly, the two ends of the lead screw 8 are respectively machined with positive and negative thread sections. When the lead screw 8 rotates, the positive and negative thread sections on the lead screw 8 drive the two threaded blocks 9 to move synchronously in opposite directions. Furthermore, by rotating the lead screw 8 clockwise or counterclockwise, the two threaded blocks 9 can move synchronously inward or outward. The threaded blocks 9 are hinged to an inclined connecting rod 10. When the threaded blocks 9 move horizontally along the lead screw 8, on the one hand, the two threaded blocks 9 move synchronously inward, and the connecting rod 10 pushes the mounting plate 7 to move downward. On the other hand, the two threaded blocks 9 move synchronously outward, and the connecting rod 10 pulls the central shaft 3 to move upward, thereby realizing that the central shaft 3 moves in the vertical direction and presses against the upper surface of the sample 20.

[0018] It is worth mentioning that a slide rail 12 is provided at the bottom of the horizontal plate 6, and a slider 13 that cooperates with the slide rail 12 is provided on the threaded block 9. The slider 13 moves along the slide rail 12 to achieve lateral movement and ensure synchronization. More importantly, the slide rail 12 bears the lateral force, preventing the lead screw 8 from deforming under radial load.

[0019] In this embodiment, the bearing assembly further includes a support shaft 14, which is disposed between the two supports 2 and located below the central shaft 3. The bending seat 4 is rotatably connected to the support shaft 14 via a support 15. This structure allows for flexible swinging of the bending seat 4. Furthermore, the support shaft 14, in conjunction with the central shaft 3 above, exerts a pressing effect on the upper surface of the sample 20, achieving bidirectional clamping. This design effectively prevents the sample 20 from moving or shifting during testing, significantly improving the stability and repeatability of the test.

[0020] In this embodiment, the telescopic rod of the hydraulic cylinder 5 is hinged to the bending seat 4 via the upper connecting plate 16, and the cylinder body of the hydraulic cylinder 5 is hinged to the base 1 via the lower connecting plate. The telescopic movement of the hydraulic cylinder 5 drives the bending seat 4 to swing, thereby applying bending load to the sample 20. It is worth noting that in this invention, the symmetrical hydraulic cylinders 5 drive the bending seat 4, applying load synchronously on both sides, ensuring uniform force distribution and avoiding uneven loading.

[0021] In addition, each of the bending seats 4 is provided with a support assembly, which includes two bearing seats 17 and driven rollers 18 disposed between the two bearing seats 17. The two driven rollers 18 press against the lower surface of the sample 20. The driven rollers 18 press against the lower surface of the sample 20 to form a support point.

[0022] One end of the lead screw 8 passes through the bracket 2 and is fixedly fitted with a handle 19. By rotating the handle 19, the lead screw 8 can be rotated clockwise or counterclockwise, thereby adjusting the vertical position of the central shaft 3.

[0023] The working principle of this utility model is as follows: Before using this bending test fixture, please refer to... Figure 4 The sample 20 is passed over the support shaft 14 and placed smoothly on the two driven rollers 18. Then, the handle 19 is turned clockwise. At this time, the two threaded blocks 9 will move inward in sync, driving the connecting rod 10 to push the mounting plate 7 downward, thereby causing the central shaft 3 to move downward until it presses against the upper surface of the sample 20, thus completing the fixation of the sample 20.

[0024] During testing, the lifting and lowering of the two hydraulic cylinders 5 are synchronously controlled by an external controller. The extension and retraction of the hydraulic cylinders 5 will drive the bending seat 4 to swing, thereby applying a bending load to the sample 20 to observe whether the material fails and the strength at the time of failure, thus evaluating the material's bending resistance under bending load.

[0025] After the test is completed, the handle 19 needs to be turned counterclockwise. At this time, the two threaded blocks 9 will move outward in sync, driving the connecting rod 10 to pull the mounting plate 7 upward, thereby causing the central shaft 3 to move upward and separate from the sample 20, making it easier to remove the sample 20 and complete the entire test process.

[0026] The embodiments described above are merely preferred embodiments of this utility model and are not intended to limit the scope of implementation of this utility model. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the patent claims of this utility model should be included within the scope of the patent application of this utility model.

Claims

1. A bending test fixture, characterized in that, The sample includes a base (1) and brackets (2) arranged on the front and rear sides above the base (1). An adjustment assembly is provided between the two brackets (2). A central shaft (3) that moves in the vertical direction is provided on the adjustment assembly. The central shaft (3) presses against the upper surface of the sample (20). A bearing assembly is hinged on the bracket (2). The bearing assembly includes bending seats (4) symmetrically arranged on the left and right sides of the bracket (2). One end of each bending seat (4) is hinged to the bracket (2). A hydraulic cylinder (5) is installed at the other end of the bending seat (4).

2. The bending test fixture according to claim 1, characterized in that, The adjustment assembly includes a horizontal plate (6) and a mounting plate (7). A lead screw (8) is provided below the horizontal plate (6). The two ends of the lead screw (8) are rotatably mounted on the bracket (2). The lead screw (8) is provided with a positive thread section and a negative thread section. The positive thread section and the negative thread section of the lead screw (8) are respectively provided with thread blocks (9). A connecting rod (10) is hinged to each of the two thread blocks (9). The mounting plate (7) is an n-shaped plate. The two ends of the central shaft (3) are rotatably mounted on the n-shaped plate. An ear seat (11) is provided on the top of the mounting plate (7). The lower ends of the connecting rods (10) are all hinged to the ear seat (11).

3. The bending test fixture according to claim 2, characterized in that, The bottom of the horizontal plate (6) is provided with a slide rail (12), and the threaded block (9) is provided with a slider (13) that cooperates with the slide rail (12).

4. The bending test fixture according to claim 1, characterized in that, The load-bearing component also includes a support shaft (14), which is disposed between two supports (2). The support shaft (14) is located below the central shaft (3), and the bending seat (4) is rotatably connected to the support shaft (14) through a support (15).

5. The bending test fixture according to claim 1, characterized in that, The telescopic rod of the oil cylinder (5) is hinged to the bending seat (4) through the upper connecting plate (16), and the cylinder body of the oil cylinder (5) is hinged to the base (1) through the lower connecting plate.

6. The bending test fixture according to claim 1, characterized in that, Each of the bending seats (4) is provided with a support assembly, which includes two bearing seats (17) and a driven roller (18) disposed between the two bearing seats (17), the two driven rollers (18) pressing against the lower surface of the sample (20).

7. The bending test fixture according to claim 2, characterized in that, One end of the lead screw (8) passes through the bracket (2) and is fixedly provided with a handle (19).

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