Elastic material testing fixture

Abstract

The application relates to an elastic material test clamping tool, and belongs to the technical field of mechanical detection auxiliary tools.The tool comprises a sample to be detected and two test clamping modules; the two test clamping modules clamp the upper and lower ends of the sample to be detected respectively; the two test clamping modules simultaneously pull the sample to be detected in the upward and downward directions to realize the test on the sample to be detected; the test clamping module comprises a base, a connecting column and a connecting fastening device; the base is a vertically placed rectangular frame structure; one end of the sample to be detected extends into the base from one side wall of the base and is clamped and fixed by the base; the connecting column is vertically arranged on the side wall of the other end of the base; the connecting column is provided with a cutout; the connecting column is connected with an external force measuring device through the cutout and is locked with the external force measuring device through the connecting fastening device; the tool can complete the elastic material test clamping, improves the clamping quality during the test on the elastic material, simultaneously guarantees the clamping force after the elastic deformation and the axial precision of the sample, and improves the test data quality.

Description

Technical Field

[0001] This invention belongs to the field of mechanical testing auxiliary tools technology, and relates to a clamping fixture for testing elastic materials. Background Technology

[0002] In the manufacturing of liquid rocket engines, rubber and plastic elastic materials are used. When testing raw materials and finished products, the elastomers need to be clamped. Because the elastomers undergo large deformations under stress, the test samples may slip or detach under stress, leading to inaccurate test results or even the inability to obtain valid data. Therefore, suitable tooling is essential to ensure accurate and reliable test results for evaluating material and product quality. Currently, conventional wedge clamps are positioning and shifting clamps. After initial clamping and fixing, the sample deforms and shrinks during testing, frequently resulting in detachment. Eccentric wheel clamps cannot guarantee that the sample's axial direction coincides with the force axis. As the sample thickness increases, transverse shear stress occurs, leading to errors in the results and failing to meet requirements. Summary of the Invention

[0003] The technical problem solved by this invention is to overcome the shortcomings of the prior art and propose a clamping fixture for testing elastic materials, which can complete the clamping of elastic materials, improve the clamping quality of elastic materials testing, and at the same time ensure the clamping force and axial accuracy of the sample after elastic deformation, thereby improving the quality of test data.

[0004] The solution of the present invention is: A testing fixture for elastic materials includes a sample to be tested and two testing clamping modules; The sample to be tested is a vertically placed rectangular sheet structure; two test clamping modules clamp the upper and lower ends of the sample to be tested respectively; the two test clamping modules simultaneously pull the sample to be tested in both upward and downward directions to achieve the test of the sample to be tested.

[0005] In the above-mentioned elastic material testing fixture, the testing fixture module includes a base, a connecting column, and a connecting fastening device; The base is a vertically placed rectangular frame structure; one end of the sample to be tested extends into the base from one side wall and is clamped and fixed by the base; the connecting column is vertically set on the other side wall of the base; the connecting column is provided with a cut hole; the connecting column is connected to the external force measuring device through the cut hole; the connecting fastening device is fitted on the outer wall of the connecting column; after the connecting column is connected to the external force measuring device, the connecting fastening device locks the connecting column and the external force measuring device.

[0006] In the aforementioned elastic material testing fixture, the base includes a main frame, a clamping device, two force-applying devices, a guide plate, and a cover plate; The main frame is a vertically placed U-shaped frame; each of the two bottom inner walls of the main frame has a bottom positioning step; each of the two top inner walls of the main frame has a top positioning step; the side wall of the main frame aligned with the sample to be tested has an opening; the two side walls of the main frame have symmetrically arranged side wall grooves; each side wall groove has an operating handle; the operating handle is connected to the force application device through a threaded hole; the clamping device is vertically arranged inside the main frame; two force application devices are arranged inside the main frame and symmetrically arranged on both sides of the clamping device; the guide plate is vertically arranged on the side wall of the clamping device; the cover plate is installed on the outer side wall of the guide plate to fix the guide plate to the side wall of the main frame.

[0007] In the aforementioned elastic material testing fixture, the cover plate is positioned and installed on the side wall of the main frame via two bottom positioning steps and two top positioning steps; the cover plate is clamped by four symmetrically distributed screws and two force-applying devices.

[0008] In the aforementioned elastic material testing fixture, the clamping device consists of two vertically opposite rectangular plate structures; each rectangular plate structure has a cylindrical connecting post at its top; each rectangular plate structure is assembled with the main frame via a corresponding cylindrical connecting post to achieve lateral movement adjustment; each rectangular plate structure has an anti-slip plate attached to its inner wall; the two anti-slip plates form a clamping working surface to clamp and fix one end of the sample to be tested; each rectangular plate structure has a guide post on its front side wall; the two guide posts cooperate with the guide plate.

[0009] In the aforementioned elastic material testing fixture, the force application device is an eccentric wheel structure; the force application device is mounted on the main frame by a long screw; a spring is provided on the force application device; the force application device and the main frame are connected by a spring.

[0010] In the aforementioned elastic material testing fixture, the force application device is controlled by an operating handle; the force application device rotates relative to the main frame with a long screw as its axis; and a constant clamping force is applied to the clamping device under the action of a spring.

[0011] In the aforementioned elastic material testing fixture, the guide plate is a vertically arranged plate structure; a guide plate handle is provided on the front side wall of the guide plate; an oblique guide groove is provided on the back of the guide plate; the guide groove cooperates with the guide post, and the clamping device can be moved laterally by moving up and down, and the center of the sample to be tested is always kept coaxial with the force application axis; guide post positioning steps are provided on both sides of the guide plate to realize assembly with the main frame and cover plate.

[0012] The working process of the above-mentioned elastic material testing fixture is as follows: Insert the connecting column into the external force measuring device, connect it with a pin through the pin hole, tighten the retaining ring, and lock the connecting column and the external force measuring device. Pull the operating handle upwards to move the guide plate upwards, and the clamping device will move to both sides. The clamping device moves to both sides to open up; place the clamping end of the sample to be tested between the two anti-slip clamping surfaces on the clamping device. Release the operating handle; the force application device pulls the clamping device towards the central axis under the action of the spring force; the anti-slip clamping surface contacts the end face of the sample to be tested and clamps it firmly; The external force measuring device begins to apply force, completing the test of the sample.

[0013] In the aforementioned elastic material testing fixture, after the external force measuring device applies a force value, the test sample deforms; the traction clamping device deforms from bottom to top; the middle area of ​​the two anti-slip clamping surfaces of the clamping device changes from a cuboid to a wedge shape; the clamping device rotates with the cylindrical connecting column as the center; under the action of the force applying device, it is adjusted to an oblique direction and continues to apply a clamping force to the test sample. During the deformation process of the test sample, the clamping working surface is always in close contact with the test sample, and the clamping force remains unchanged.

[0014] The advantages of this invention compared to the prior art are: (1) The present invention can realize efficient clamping in the process of elastic material testing, and has the advantages of simple structure, novel design, reliable clamping and strong applicability; (2) The present invention is lightweight and its connection structure is compatible with the interface of ordinary testing machines, allowing it to be used directly on electronic universal testing machines; (3) The part of the present invention that contacts the sample is made of elastic anti-slip material, which effectively avoids the risk of movement and slippage during the test. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the upper part of the elastic material testing clamping fixture of the present invention; Figure 2 This is a schematic diagram of the main framework of the present invention; Figure 3 This is a schematic diagram of one of the rectangular plate-shaped structures in the clamping device of the present invention; Figure 4 This is a schematic diagram of the guide plate of the present invention. Detailed Implementation

[0016] The present invention will be further described below with reference to the embodiments.

[0017] This invention provides a clamping fixture for testing elastic materials, which can complete the clamping of elastic materials, improve the clamping quality of elastic material testing, and at the same time ensure the clamping force and axial accuracy of the sample after elastic deformation, thereby improving the quality of test data.

[0018] The elastic material testing fixture includes a sample 100 to be tested and two testing clamping modules. The sample 100 is a vertically placed rectangular sheet structure; the two testing clamping modules clamp the upper and lower ends of the sample 100 respectively; the two testing clamping modules simultaneously pull the sample 100 in both upward and downward directions to achieve the testing of the sample 100.

[0019] like Figure 1 , Figure 2 As shown, the test clamping module includes a base 1, a connecting column 2, and a connecting fastening device 4. The base 1 is a vertically placed rectangular frame structure; one end of the sample 100 to be tested extends into the base 1 from one side wall and is clamped and fixed by the base 1; the connecting column 2 is vertically arranged on the other side wall of the base 1; the connecting column 2 has a notched hole 3; the connecting column 2 is connected to an external force measuring device through the notched hole 3; the connecting fastening device 4 is fitted onto the outer wall of the connecting column 2; after the connecting column 2 is connected to the external force measuring device, the connecting fastening device 4 locks the connecting column 2 and the external force measuring device together.

[0020] In this invention, the base 1 includes a main frame 11, a clamping device 16, two force-applying devices 17, a guide plate 18, and a cover plate 19. The main frame 11 is a vertically placed U-shaped frame; a bottom positioning step 12 is provided on each of the two inner walls at the bottom of the main frame 11; a top positioning step 13 is provided on each of the two inner walls at the top of the main frame 11; a window 14 is provided on the side wall of the main frame 11 aligned with the sample 100 to be tested; side wall grooves 15 are symmetrically provided on both sides of the main frame 11; an operating handle 151 is provided in each side wall groove 15; the operating handle 151 is connected to the force application device 17 through a threaded hole; the clamping device 16 is vertically arranged inside the main frame 11; two force application devices 17 are arranged inside the main frame 11 and symmetrically arranged on both sides of the clamping device 16; a guide plate 18 is vertically arranged on the side wall of the clamping device 16; a cover plate 19 is installed on the outer side wall of the guide plate 18 to fix the guide plate 18 to the side wall of the main frame 11.

[0021] The cover plate 19 is positioned and installed on the side wall of the main frame 11 by two bottom positioning steps 12 and two top positioning steps 13; the cover plate 19 is clamped by four symmetrically distributed screw clamping devices 16 and two force application devices 17.

[0022] like Figure 3As shown, the clamping device 16 consists of two vertically placed rectangular plate-shaped structures; each rectangular plate-shaped structure has a cylindrical connecting post 162 at its top; each rectangular plate-shaped structure is assembled with the main frame 11 through the corresponding cylindrical connecting post 162 to achieve lateral movement adjustment; each rectangular plate-shaped structure has an anti-slip plate 163 attached to its inner wall; the two anti-slip plates 163 form a clamping working surface 164 to clamp and fix one end of the sample 100 to be tested; each rectangular plate-shaped structure has a guide post 161 on its front side wall; the two guide posts 161 cooperate with the guide plate 18.

[0023] The force-applying device 17 of this invention is an eccentric wheel structure; the force-applying device 17 is mounted on the main frame 11 by a long screw 171; a spring 172 is provided on the force-applying device 17; the force-applying device 17 and the main frame 11 are connected by the spring 172. The force-applying device 17 is controlled by the operating handle 151; the force-applying device 17 rotates relative to the main frame 11 with the long screw 171 as the axis; and applies a constant clamping force to the clamping device 16 under the action of the spring 172.

[0024] like Figure 4 As shown, the guide plate 18 is a vertically arranged plate structure; a guide plate handle 181 is provided on the front side wall of the guide plate 18; an oblique guide groove 182 is provided on the back of the guide plate 18; the guide groove 182 cooperates with the guide post 161, and the clamping device 16 is moved laterally by moving up and down, and the center of the sample 100 to be tested is always kept coaxial with the force axis; guide post positioning steps 184 are provided on both sides of the guide plate 18 to realize the assembly with the main frame 11 and the cover plate 19.

[0025] The working process of the elastic material testing fixture is as follows: Insert the connecting post 2 into the external force measuring device, connect it with a pin through the pin hole 3, tighten the retaining ring 4, and lock the connecting post 2 to the external force measuring device.

[0026] Pull the operating handle 151 upwards, move the guide plate 18 upwards, and move the clamping device 16 to both sides.

[0027] The clamping device 16 moves to both sides to open up; the clamping end of the sample 100 to be tested is placed between the two anti-slip clamping surfaces 163 on the clamping device 16.

[0028] Release the operating handle 151; under the spring force of the spring 172, the force application device 17 pulls the clamping device 16 to move towards the central axis; the anti-slip clamping surface 163 contacts the end face of the sample to be tested 100 and clamps it firmly.

[0029] The external force measuring device begins to apply force, completing the test of sample 100.

[0030] After the external force measuring device applies a force value, the sample 100 to be tested deforms; the traction clamping device 16 deforms from bottom to top; the middle area of ​​the two anti-slip clamping surfaces 163 of the clamping device 16 changes from a cuboid to a wedge shape; the clamping device 16 rotates with the cylindrical connecting column 162 as the center; under the action of the force applying device 17, it is adjusted to an oblique direction and continues to apply a clamping force to the sample 100 to be tested. During the deformation of the sample 100 to be tested, the clamping working surface 164 is always in close contact with the sample 100 to be tested, and the clamping force remains unchanged.

[0031] This invention features high-efficiency clamping and constant-stress clamping, effectively solving the problems of low clamping efficiency and easy slippage in existing elastic material testing.

[0032] The sample 100 to be tested in this invention is clamped by the side of the anti-slip plate 163. The clamping device 16 generates a constant clamping stress under the action of the force application device 17. During the deformation of the elastic sample, the clamping device 16 will rotate accordingly to keep the clamping surface in close contact with the sample surface. The top of the clamping device 16 is connected to the base 1 and the cover plate 19 on both sides through the cylindrical connecting column 162, which can produce lateral movement and circumferential rotation.

[0033] Furthermore, the upper surface of the base has a connecting post 2 corresponding to the force measuring device at its center. It is connected to the force measuring device through a pin hole 3. After connection, the fastening ring 4 can lock the tooling and the external force measuring device.

[0034] The base 1 has positioning steps 11 on both sides of its lower interior for positioning the guide plate 18. The upper sides have positioning steps 12 for positioning the cover plate 19. Grooves 15 are cut in the middle of both sides for moving the operating handle 151. A guide hole 14 is located at the bottom for the guide plate guide post 183 to move up and down. A window 13 is opened at the bottom, and the lower end of the clamping device 16 mates with the outlet.

[0035] The clamping device 16 has a connecting post 162 on the top and one on each side, which contacts the base and is the force-applying part during operation. The two mirror clamping devices are a set and are assembled inside the base. The lower end has a guide post 181 that cooperates with the guide groove 182. The reference surface is fixed with the anti-slip plate 163. The other side of the anti-slip plate 163 is the clamping working surface 164.

[0036] The force application device 17 consists of a set of eccentric wheels with a mirror structure, which are fixed to the base 1 by a long screw 171. It can rotate along the long screw 171 and generate a constant clamping stress under the action of the spring 172. It can be controlled by the operating handle 151.

[0037] The guide plate 18 has an oblique guide groove 182 on its back, which cooperates with the positioning post 161 of the clamping device 16. The clamping device 16 can move laterally by moving up and down, and the center line of the sample is always coaxial with the force axis. The guide plate 18 has positioning steps 164 on both sides, and the lower two sides are respectively assembled with the base and the cover plate. The bottom has a cylinder 183 assembled with the core of the spring 185, which extends into the step hole 14 of the base.

[0038] The cover plate 19 is mounted on the clamping device 16, the force application device 17, and the guide plate 18, and is fixed to the base 1 by four screws 191 at the four corners.

[0039] This invention enables efficient clamping during the testing of elastic materials, offering advantages such as simple structure, novel design, reliable clamping, and wide applicability. The entire fixture is lightweight, and its connection structure is compatible with interfaces on ordinary testing machines, allowing direct use on electronic universal testing machines.

[0040] The contact area between the present invention and the sample is made of elastic anti-slip material, which effectively avoids the risk of movement and slippage during the test. Throughout the test, the clamping device 16 is in close contact with the sample 100 to be tested, and the clamping is firm, without slippage or falling off.

[0041] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A fixture for testing elastic materials, characterized in that: Includes 100 samples to be tested and 2 test clamping modules; The sample to be tested (100) is a vertically placed rectangular sheet structure; two test clamping modules clamp the upper and lower ends of the sample to be tested (100) respectively; the two test clamping modules simultaneously pull the sample to be tested (100) in the upward and downward directions to realize the test of the sample to be tested (100).

2. The elastic material testing fixture according to claim 1, characterized in that: The test clamping module includes a base (1), a connecting column (2), and a connecting fastening device (4). Among them, the base (1) is a vertically placed rectangular frame structure; one end of the sample to be tested (100) extends into the base (1) from one of the side walls of the base (1) and is clamped and fixed by the base (1); the connecting column (2) is vertically set on the other side wall of the base (1); the connecting column (2) is provided with a shaving hole (3); the connecting column (2) is connected to the external force measuring device through the shaving hole (3); the connecting fastening device (4) is fitted on the outer wall of the connecting column (2); after the connecting column (2) is connected to the external force measuring device, the connecting column (2) and the external force measuring device are locked by the connecting fastening device (4).

3. The elastic material testing fixture according to claim 2, characterized in that: The base (1) includes a main frame (11), a clamping device (16), two force-applying devices (17), a guide plate (18), and a cover plate (19). The main frame (11) is a vertically placed U-shaped frame; a bottom positioning step (12) is provided on the inner walls of the bottom two sides of the main frame (11); a top positioning step (13) is provided on the inner walls of the top two sides of the main frame (11); a window (14) is opened on the side wall of the main frame (11) aligned with the sample (100) to be tested; side wall grooves (15) are symmetrically provided on the two side walls of the main frame (11); an operating handle (1) is provided in each side wall groove (15). 51); the operating handle (151) is connected to the force application device (17) through a threaded hole; the clamping device (16) is vertically set inside the main frame (11); two force application devices (17) are set inside the main frame (11) and symmetrically set on both sides of the clamping device (16); the guide plate (18) is vertically set on the side wall of the clamping device (16); the cover plate (19) is installed on the outer side wall of the guide plate (18) to fix the guide plate (18) on the side wall of the main frame (11).

4. The elastic material testing fixture according to claim 3, characterized in that: The cover plate (19) is positioned and installed on the side wall of the main frame (11) by two bottom positioning steps (12) and two top positioning steps (13); the cover plate (19) is clamped by four symmetrically distributed screw clamping devices (16) and two force application devices (17).

5. The elastic material testing fixture according to claim 3, characterized in that: The clamping device (16) consists of two vertically placed rectangular plate structures; each rectangular plate structure has a cylindrical connecting column (162) at its top; each rectangular plate structure is assembled with the main frame (11) through the corresponding cylindrical connecting column (162) to achieve lateral movement adjustment; each rectangular plate structure has an anti-slip plate (163) attached to its inner wall; the two anti-slip plates (163) form a clamping working surface (164) to clamp and fix one end of the sample to be tested (100); each rectangular plate structure has a guide column (161) on its front side wall; the two guide columns (161) cooperate with the guide plate (18).

6. The elastic material testing fixture according to claim 5, characterized in that: The force-applying device (17) is an eccentric wheel structure; the force-applying device (17) is installed on the main frame (11) by a long screw (171); a spring (172) is provided on the force-applying device (17); the force-applying device (17) and the main frame (11) are connected by the spring (172).

7. The elastic material testing fixture according to claim 6, characterized in that: The force application device (17) is controlled by the operating handle (151); the force application device (17) rotates relative to the main frame (11) with the long screw (171) as the axis; and applies a constant clamping force to the clamping device (16) under the action of the spring (172).

8. The elastic material testing fixture according to claim 5, characterized in that: The guide plate (18) is a vertically arranged plate structure; a guide plate handle (181) is provided on the front side wall of the guide plate (18); an oblique guide groove (182) is provided on the back of the guide plate (18); the guide groove (182) cooperates with the guide post (161) to realize the lateral movement of the clamping device (16) by moving up and down, and the center of the sample to be tested (100) is always coaxial with the force axis; guide post positioning steps (184) are provided on both sides of the guide plate (18) to realize the assembly with the main frame (11) and the cover plate (19).

9. The elastic material testing fixture according to claim 7, characterized in that: The work process is as follows: Insert the connecting column (2) into the external force measuring device, connect it with a pin through the pin hole (3), tighten the retaining ring (4), and lock the connecting column (2) and the external force measuring device. Pull the operating handle (151) upwards, move the guide plate (18) upwards, and move the clamping device (16) to both sides; The clamping device (16) moves to both sides to open up; the clamping end of the test sample (0) is placed between the two anti-slip clamping surfaces (163) on the clamping device (16); Release the operating handle (151); the force application device (17) pulls the clamping device (16) to move towards the central axis under the spring force of the spring (172); the anti-slip clamping surface (163) contacts the end face of the test sample (0) and clamps it firmly; The external force measuring device begins to apply a force value, completing the test of the test sample (0).

10. The elastic material testing fixture according to claim 9, characterized in that: After the external force measuring device applies the force value, the test sample (0) deforms; the traction clamping device (16) deforms from bottom to top; the middle area of ​​the two anti-slip clamping surfaces (163) of the clamping device (16) changes from a cuboid to a wedge shape; the clamping device (16) rotates with the cylindrical connecting column (162) as the center; under the action of the force applying device (17), it is adjusted to be inclined and continues to apply the clamping force to the test sample (0). During the deformation process of the test sample (0), the clamping working surface (164) is always in close contact with the test sample (0), and the clamping force remains unchanged.

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