Manual adjustment double-shaft pretension flat plate type test piece impact test clamp

Abstract

The utility model discloses a manual adjustment double-shaft pretension flat plate type test piece impact test fixture, which belongs to the technical field of tool fixtures, and comprises an L-shaped clamping block and two rectangular clamping blocks, the L-shaped clamping block and the two rectangular clamping blocks form a rectangular frame fixture, the rectangular frame fixture clamps and fixes a test piece from four ends, and the test piece is clamped by the rectangular frame fixture. The center of each L-shaped clamping block is provided with a fixture fixing bolt, the fixture fixing bolts fix the rectangular frame fixture to facilitate positioning in a subsequent impact experiment, the outer side surfaces of the two rectangular clamping blocks are both provided with tensioning devices, and the tensioning devices apply pre-tension force to the rectangular clamping blocks through the cooperation of hard springs and screw rods, so that the rectangular frame fixture can be positioned in the subsequent impact experiment. The two tensioning devices respectively apply pretension force from two directions, and different application conditions of the pretension force can be simulated. According to the flat plate type test piece impact test fixture capable of manually adjusting the pretension force of the double shafts, the test piece is clamped by the rectangular frame fixture, and the pretension force is applied to the test piece by the tensioning device.

Description

Technical Field

[0001] The utility model relates to the technical field of tooling fixtures, in particular to a manually adjustable biaxial pre-tension flat plate type test piece impact test fixture. Background Art

[0002] In recent years, hydrogen-powered vehicles have gained an opportunity for rapid development. As a key special equipment in modern industry, composite wrapped gas cylinders are used in the field of hydrogen-powered vehicles due to their advantages such as large volume and light weight, and are mainly used for the storage of high-pressure hydrogen. From the time the composite hydrogen storage cylinder leaves the factory, it will go through the stages of transportation, installation, storage, use, and maintenance. In each stage, the hydrogen storage cylinder may encounter dynamic impact loads from human or environmental sources. Once the hydrogen storage cylinder is damaged by impact, it will cause serious hidden dangers to the safety performance of the cylinder. Therefore, before the composite material is truly applied to actual industrial applications, its impact resistance needs to be assessed through a large number of flat plate impact tests, and the impact test research of composite materials is of great significance for the design of impact protection performance of composite hydrogen storage cylinders. At present, during the service of composite hydrogen storage cylinders, the high-pressure hydrogen inside will cause a certain biaxial pre-tension to the composite gas cylinder itself. However, in the current impact test standard for flat specimens, the existence of pre-tension is not considered, but the existence of pre-tension will have a greater impact on the impact damage of the material. At present, there are a small number of impact test fixtures that can realize the loading of pre-tension for impact tests on flat specimens, but these devices have certain limitations. Either they can only realize unidirectional pre-tension loading and cannot meet the biaxial pre-tension loading requirements of flat specimens, or the pre-tension loading process needs to be driven by a motor or a hydraulic cylinder, which is often large in size and the overall device is relatively complex, which is not conducive to small-scale experiments and cannot meet the requirements of test efficiency and portability of impact test fixtures. Utility Model Content

[0003] The purpose of the utility model is to provide a manually adjustable biaxial pre-tension flat plate specimen impact test fixture, which is used to clamp metal or composite material flat plate specimens. The fixture applies biaxial pre-tension to the specimen by rotating the screw rod and cooperating with the movable plate and the hard spring, fixing one end and releasing the degree of freedom in one direction at the other end, and manually twisting the threaded rod, so as to realize the impact test of the specimen under the condition of bearing biaxial pre-tension. At the same time, by adjusting the number of rotations, different sizes of pre-tension in different directions can be set.

[0004] To achieve the above-mentioned purpose, the utility model provides a manually adjustable biaxial pre-tensioned flat plate specimen impact test fixture, including an L-shaped clamp block and two rectangular clamp blocks, the L-shaped clamp block and the two rectangular clamp blocks form a rectangular frame clamp, a clamp fixing bolt is arranged at the center position of the L-shaped clamp block, and the outer sides of the two rectangular clamp blocks are vertically provided with tensioning devices.

[0005] Preferably, the L-shaped clamp block and the rectangular clamp block are both configured as a double-layer structure, the L-shaped clamp block includes an L-shaped upper clamp plate and an L-shaped lower clamp plate, the rectangular clamp block includes a rectangular upper clamp plate and a rectangular lower clamp plate, and the double-layer structures of the L-shaped clamp block and the rectangular clamp block are connected up and down by bolts.

[0006] Preferably, the tensioning device includes a connecting plate arranged on the outer side of the rectangular clamping block, a plurality of hard springs are arranged on the connecting plate, the other end of the hard spring passes through the rectangular fixed bottom plate to connect to the rectangular movable plate, both ends of the fixed bottom plate are provided with horizontal support rods passing through the movable plate and connected to the rectangular fixed top plate, a threaded hole is arranged at the center position of the fixed top plate, and a screw is arranged to pass through the threaded hole and be connected to the center position of the movable plate through a fixed sleeve.

[0007] Preferably, a rotating handle is provided on the outer end of the screw.

[0008] Preferably, the connecting plate and the rectangular clamping block are fixed by screws.

[0009] Preferably, the connecting plate, the fixed bottom plate, the movable plate and the fixed top plate are all arranged in parallel in the same horizontal plane.

[0010] Therefore, the utility model adopts a manually adjustable biaxial pre-tensioned flat plate specimen impact test fixture of the above structure, which has the following beneficial effects:

[0011] (1) In the utility model, a circular groove is provided on the movable plate, and a sleeve and a screw are used to fix the screw rod and the movable plate. At the same time, the screw rod rotates and moves the movable plate through the threaded hole on the fixed top plate, thereby driving the hard spring to apply pre-tension to the specimen, thereby realizing the function of applying biaxial pre-tension of different sizes in two directions.

[0012] (2) In the present invention, the pre-tensioning force is transmitted between the connecting plate and the fixed base plate in the tensioning device through a hard spring, thereby realizing the transmission function of the biaxial pre-tensioning force.

[0013] (3) In the present invention, the tensioning device adopts a manual rotation screw method. Compared with the currently commonly used electric method, the manual method is more suitable for testing small specimens and can conveniently control the size of the pre-tensioning force.

[0014] The technical solution of the utility model is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic structural diagram of a manually adjustable biaxial pre-tension flat plate specimen impact test fixture of the utility model;

[0016] Figure 2 It is an exploded schematic diagram of a manually adjustable biaxial pre-tension flat plate type specimen impact test fixture structure of the utility model;

[0017] Figure numerals: 1. clamp fixing bolt; 2. L-shaped upper clamp; 3. L-shaped lower clamp; 4. rectangular upper clamp; 5. rectangular lower clamp; 6. connecting plate; 7. screw; 8. hard spring; 9. movable plate; 10. fixed bottom plate; 11. support rod; 12. fixed top plate; 13. screw; 14. rotating handle. DETAILED DESCRIPTION

[0018] The technical solution of the utility model is further described below through the accompanying drawings and embodiments.

[0019] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the usual meanings understood by persons with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" and the like mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0020] Example

[0021] like Figure 1-2The utility model provides a manually adjustable biaxial pre-tension flat plate specimen impact test fixture, including an L-shaped clamp block and two rectangular clamp blocks. The L-shaped clamp block and the rectangular clamp block are both set as a double-layer structure. The double-layer structure is used to clamp the horizontally placed flat plate specimen. The L-shaped clamp block includes an L-shaped upper clamp plate 2 and an L-shaped lower clamp plate 3. The rectangular clamp block includes a rectangular upper clamp plate 4 and a rectangular lower clamp plate 5. The double-layer structures of the L-shaped clamp block and the rectangular clamp block are connected up and down by bolts. After placing the specimen, tighten the bolts and use the bolts to clamp and fix the flat plate specimen. The L-shaped clamp block and the two rectangular clamp blocks form a rectangular frame clamp, which can clamp the flat specimen from four directions in total. A clamp fixing bolt 1 is arranged at the center of the L-shaped clamp block. The clamp fixing bolt 1 is arranged to penetrate the L-shaped clamp block, and can fix the clamp in position during the test to avoid the clamp from shifting when the impact test is performed. The outer sides of the two rectangular clamp blocks are vertically provided with tensioning devices, which are used to apply pre-tensioning force. The tensioning device includes a connecting plate 6 arranged on the outer side of the rectangular clamp block, and the connecting plate 6 and the rectangular clamp block are connected by screws 7 A fixed connection is performed to pull the rectangular clamp block to apply pre-tension. A plurality of hard springs 8 are arranged on the connecting plate 6. The other end of the hard spring 8 passes through the rectangular fixed bottom plate 10 to connect the rectangular movable plate 9. Both ends of the fixed bottom plate 10 are provided with horizontal support rods 11 that pass through the movable plate 9 and are connected to the rectangular fixed top plate 12. The support rods 11 connect the fixed bottom plate 10 with the fixed top plate 12 and form a rectangular frame. The movable plate 9 slides up and down along the support rods 11. A threaded hole is arranged at the center of the fixed top plate 12. A screw rod 13 is arranged to pass through a threaded hole and be connected to the center position of the movable plate through a fixed sleeve. The movable plate 9 is moved back and forth by rotating the screw rod 13 in the threaded hole. During the movement of the movable plate 9, the hard spring 8 is involved. The hard spring 8 deforms and pulls the connecting plate 6, thereby applying a pre-tension to the specimen. A rotating handle 14 is provided at the outer end of the screw rod 13 to facilitate the rotation of the screw rod 13. The connecting plate 6, the fixed bottom plate 10, the movable plate 9 and the fixed top plate 12 are all arranged in parallel in the same horizontal plane, so as to facilitate the application of a horizontal pre-tension to the specimen.

[0022] In specific use, the flat-plate specimen is placed on the L-shaped lower clamp in the L-shaped clamp, and the L-shaped upper clamp is installed and fixed with bolts. The L-shaped clamp fixes two axial directions of the specimen, and the other two axial directions are fixed through the double-layer structure of the rectangular clamp to achieve clamping of the four ends of the flat-plate specimen. After fixing the specimen, the clamp is fixed with the clamp fixing bolts to facilitate subsequent impact tests. Then, the screws on the two tensioning devices are used to apply pre-tension. The screws rotate in the threaded holes and cooperate to pull the movable plate backward. The movement of the movable plate will lengthen the hard spring, and the hard spring will pull the rectangular clamp outward to apply pre-tension to the specimen clamped therein. The displacement distance of the movable plate determines the size of the traction force applied.

[0023] Therefore, the utility model adopts a manually adjustable biaxial pre-tensioned flat plate specimen impact test fixture of the above-mentioned structure, which is used to clamp metal or composite material flat plate specimens. The fixture applies biaxial pre-tension to the specimen by rotating the screw and cooperating with the movable plate and the hard spring. One end is fixed and the other end releases the freedom in a single direction. The biaxial pre-tension is applied to the specimen by manually twisting the threaded rod. The specimen can be subjected to impact testing under biaxial pre-tension. At the same time, pre-tensions of different sizes in different directions can be set by adjusting the number of rotation circles.

[0024] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that they can still modify or replace the technical solution of the utility model with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the utility model.

Claims

1. A manually adjustable biaxial pre-tension flat plate specimen impact test fixture, characterized in that: It comprises an L-shaped clamp block and two rectangular clamp blocks, wherein the L-shaped clamp block and the two rectangular clamp blocks form a rectangular frame clamp, a clamp fixing bolt is arranged at the center position of the L-shaped clamp block, and tensioning devices are arranged vertically on the outer sides of the two rectangular clamp blocks.

2. A manually adjustable biaxial pre-tension flat plate specimen impact test fixture according to claim 1, characterized in that: The L-shaped clamp block and the rectangular clamp block are both configured as double-layer structures, the L-shaped clamp block includes an L-shaped upper clamp plate and an L-shaped lower clamp plate, the rectangular clamp block includes a rectangular upper clamp plate and a rectangular lower clamp plate, and the double-layer structures of the L-shaped clamp block and the rectangular clamp block are both connected up and down by bolts.

3. A manually adjustable biaxial pre-tension flat plate specimen impact test fixture according to claim 2, characterized in that: The tensioning device includes a connecting plate arranged on the outer side of the rectangular clamping block, and a plurality of hard springs are arranged on the connecting plate. The other end of the hard spring passes through the rectangular fixed bottom plate to connect to the rectangular movable plate. Both ends of the fixed bottom plate are provided with horizontal support rods that pass through the movable plate and are connected to the rectangular fixed top plate. A threaded hole is arranged at the center position of the fixed top plate, and a screw is arranged to pass through the threaded hole and be connected to the center position of the movable plate through a fixed sleeve.

4. A manually adjustable biaxial pre-tensioned flat plate specimen impact test fixture according to claim 3, characterized in that: The outer end of the screw rod is provided with a rotating handle.

5. A manually adjustable biaxial pre-tension flat plate specimen impact test fixture according to claim 4, characterized in that: The connecting plate and the rectangular clamping block are fixed by screws.

6. A manually adjustable biaxial pre-tension flat plate specimen impact test fixture according to claim 5, characterized in that: The connecting plate, the fixed bottom plate, the movable plate and the fixed top plate are all arranged in parallel in the same horizontal plane.

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