Clamp for friction stir welding

Abstract

The utility model provides a kind of clamp for friction stir welding, it is related to clamp technical field, including workbench, workbench is provided with workpiece bearing base, workpiece bearing base is provided with moving batten assembly and scale batten assembly;The scale batten assembly includes second lifting power component, the output end of second lifting power component is connected second batten, and scale mark is provided on second batten.This utility model's advantage is, by setting first batten and second batten, and setting positioning block on first batten and scale mark on second batten, to greatly facilitate the placement of workpiece, avoid personnel multiple alignment and thereby save a lot of operation time, so that every workpiece is placed on workpiece bearing base in turn can be accurately positioned, and the welding condition of different welding positions and the temperature test of different welding positions are convenient to observe by scale mark, conducive to later research and analysis work.

Description

Technical Field

[0001] This utility model relates to the field of fixture technology, and in particular to fixtures used in friction stir welding. Background Technology

[0002] Friction stir welding (FSW) is a novel material joining technology invented by the Welding Institute (TWI) in the UK in 1991. Its working principle involves inserting a specially designed stirring head into the workpiece to be welded. The stirring head rotates at high speed, generating friction and stirring with the workpiece. The resulting frictional heat brings the metal in that area to a thermoplastic state. Under the pressure of the stirring head, the metal plastically flows from the front to the rear of the stirring head, ultimately pressing the workpieces together to form a single unit.

[0003] Compared to traditional welding methods, friction stir welding (FSW) offers significant advantages. It is highly efficient, environmentally friendly, requires no special gas shielding, and is cost-effective, while avoiding many common problems associated with traditional welding. Specifically, FSW joints exhibit minimal microstructural changes in the heat-affected zone, low residual stress, and are less prone to workpiece deformation. It can complete long welds, large cross-sections, and welds in different locations in a single operation. Operation is easily mechanized and automated, requiring simple equipment, low energy consumption, high efficiency, and undemanding operating environments. No welding wire is needed during welding, and when welding aluminum alloys, pre-weld oxide film removal is unnecessary, as is shielding gas, further reducing costs. Furthermore, it is suitable for welding hot-cracking sensitive materials and dissimilar materials, and the welding process is safe, pollution-free, smoke-free, and radiation-free. Compared to traditional fusion welding methods, it is not limited to shaft parts, and the post-weld joint exhibits low internal stress and minimal deformation, enabling low-stress, deformation-free welding of sheet metal.

[0004] However, friction stir welding is prone to quality defects such as localized weld deformation during the welding process. Analysis shows that this is mainly due to the central area of ​​the weld at the intermediate joint not being clamped tightly, or the weld having a gap with the tooling table.

[0005] To address the aforementioned issues, some existing friction stir welding fixtures on the market employ a covering low-pressure method across different positions of the workpiece to clamp it as a whole, ensuring a tight fit between the workpiece and the fixture table from edge to center, thereby reducing quality problems. However, this type of fixture also has limitations. During experimental parameter testing or mass production of parts, it is difficult to guarantee consistent workpiece placement each time, thus affecting the reliability of experimental parameters and the stability of product quality. The technical content disclosed in Chinese patent document (Publication No.: CN204018958U, Patent Name: A Multifunctional Fixture for Friction Stir Welding) is as follows: It includes a base, a pad, quick clamps, a vertical pressure plate, and lateral tightening screws; the base is fixed to a machine tool platform, and an inner groove is provided inside the base. The pad is placed in the inner groove of the base. Quick clamps are arranged on both sides of the base, and the quick clamps connected to the base clamp the workpiece to be welded through the vertical pressure plate. The lateral tightening screws are located through staggered screw holes on both sides of the base. Compared with the prior art, the friction stir welding fixture of this utility model can weld a variety of structural forms, and is particularly suitable for welding thin-walled workpieces; and the fixture body has the characteristics of simple structure, convenient operation and good welding stability.

[0006] As can be seen from the content of the aforementioned patent documents, this multi-functional fixture lacks a corresponding positioning mechanism. This means that the operator must perform the calibration themselves each time a workpiece is placed, which is cumbersome and may lead to inaccurate experimental data or unstable product quality due to inaccurate calibration. Utility Model Content

[0007] The utility model overcomes the shortcomings of the prior art and provides a fixture for friction stir welding. By setting a first pressure bar and a second pressure bar, and setting a positioning block on the first pressure bar and setting a scale mark on the second pressure bar, the placement of the workpiece is greatly facilitated, avoiding multiple alignments by personnel and saving a lot of operation time. This ensures that each workpiece can be accurately positioned when it is placed on the workpiece support base in turn.

[0008] To solve the above-mentioned technical problems, the utility model is implemented through the following technical solution:

[0009] A fixture for friction stir welding includes a worktable, a workpiece support base on the worktable, and a movable pressure bar assembly and a graduated pressure bar assembly on the workpiece support base.

[0010] The scale pressure bar assembly includes a second lifting power component, the output end of which is connected to the second pressure bar, and the second pressure bar is provided with scale markings.

[0011] The movable pressure bar assembly includes a first lifting power component, the output end of which is connected to the first pressure bar, and the distance between the first pressure bar and the second pressure bar is adjustable;

[0012] A positioning block is also provided on the side of the first pressure strip near the second pressure strip.

[0013] Furthermore, the first pressure strip and the second pressure strip are arranged in parallel;

[0014] The zero point of the scale marking is coplanar with the reference plane of the positioning block.

[0015] Furthermore, the movable pressure bar assembly includes a movable adjustment motor, which is connected to a movable adjustment screw. The movable adjustment screw is threadedly connected to a first lifting power component. When the movable adjustment motor drives the movable adjustment screw to rotate, the first lifting power component moves along the length direction of the movable adjustment screw.

[0016] Furthermore, the movable adjusting screw is provided with a movable adjusting slide rail in parallel, and the first lifting power component is slidably connected to the movable adjusting slide rail.

[0017] Furthermore, the workpiece support base is connected to the worktable by bolts, and side support blocks are also provided on both sides of the workpiece support base.

[0018] Furthermore, the workpiece support base is provided with edge pressure block assemblies around its perimeter;

[0019] The edge pressing block assembly includes a third lifting power component, the output end of which is connected to the pressing block, which is located directly above the workpiece bearing base.

[0020] Furthermore, the first lifting power component, the second lifting power component, and the third lifting power component are cylinders or electric cylinders.

[0021] Furthermore, the positioning block is embedded with a strain gauge sensor for detecting workpiece clamping stress.

[0022] Furthermore, the scale markings are made using laser etching technology, achieving a scale accuracy of ±0.05mm.

[0023] Compared with existing technologies, the advantages of this utility model are:

[0024] 1. By setting a first pressure bar and a second pressure bar, and setting a positioning block on the first pressure bar and a scale mark on the second pressure bar, the placement of the workpiece is greatly facilitated, avoiding multiple alignments by personnel and saving a lot of operation time, so that each workpiece can be accurately positioned when it is placed on the workpiece support base in turn.

[0025] 2. The scale markings facilitate observation of the welding status at different welding positions and temperature testing at different welding positions, which is beneficial for subsequent scientific research.

[0026] 3. By setting the first and second pressure bars, a structure combining the calibration rod and pressure bar is achieved, which saves materials and reduces operation time. The first and second pressure bars completely cover the middle part of the workpiece, which greatly improves the flatness and deformation of the workpiece after welding, and keeps the workpiece in the same position, thereby ensuring the reliability of experimental parameters and the stability of product quality. Attached Figure Description

[0027] The accompanying drawings are provided to further illustrate the utility model and, together with the embodiments of the utility model, are used to explain the utility model. They do not constitute a limitation on the utility model. In the drawings:

[0028] Figure 1 This is a schematic diagram of the overall structure of the clamp according to an embodiment of the present utility model;

[0029] Figure 2 This is a top view of the clamp according to an embodiment of the present utility model;

[0030] Figure 3 This is an exploded view of the clamp according to an embodiment of the present invention.

[0031] In the diagram: 1. Workbench; 2. Workpiece support base; 201. Side support block; 3. Moving pressure bar assembly; 301. Moving adjustment motor; 302. Moving adjustment screw; 303. Moving adjustment slide rail; 304. First lifting power component; 305. First pressure bar; 3051. Positioning block; 4. Scale pressure bar assembly; 401. Second lifting power component; 402. Second pressure bar; 4021. Scale marking; 5. Side pressure block assembly; 501. Pressure block; 502. Third lifting power component. Detailed Implementation

[0032] The preferred embodiments of the utility model are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the utility model.

[0033] like Figures 1 to 3 As shown, a fixture for friction stir welding includes a worktable 1. The worktable 1 is the basic support component of the entire fixture, ensuring that the fixture will not shake due to external vibration or operating force during the friction stir welding process, providing a stable working environment for welding and helping to improve welding accuracy.

[0034] The workbench 1 is equipped with a workpiece support base 2, which supports the workpiece to be welded and provides a flat surface for placement and positioning. The workpiece support base 2 is connected to the workbench 1 by bolts, facilitating installation and disassembly, and allowing for easy replacement of bases of different specifications according to different welding requirements. Side support blocks 201 are also provided on both sides of the workpiece support base 2. The side support blocks 201 are triangular in shape and are used to enhance the support stability of the base.

[0035] The workpiece support base 2 is surrounded by a side pressure block assembly 5. The side pressure block assembly 5 consists of a third lifting power component 502 and a pressure block 501. The output end of the third lifting power component 502 is connected to the pressure block 501. The pressure block 501 is located directly above the workpiece support base 2 and can assist in pressing the workpiece placed on the base.

[0036] The workpiece support base 2 is equipped with a movable pressure strip assembly 3 and a scale pressure strip assembly 4;

[0037] The scale pressure bar assembly 4 includes a second lifting power component 401, the output end of the second lifting power component 401 is connected to the second pressure bar 402, and the second pressure bar 402 is provided with a scale mark 4021.

[0038] The movable pressure bar assembly 3 includes a first lifting power component 304. The output end of the first lifting power component 304 is connected to the first pressure bar 305. The first lifting power component 304 drives the first pressure bar 305 to rise and fall, which is used to press or release the workpiece.

[0039] The distance between the first pressure bar 305 and the second pressure bar 402 is adjustable; therefore, the distance between them can be adjusted according to the actual size of the workpiece during use, increasing the range of applications of the fixture.

[0040] The first pressure bar 305 and the second pressure bar 402 are arranged parallel to each other. A positioning block 3051 is also provided on the side of the first pressure bar 305 near the second pressure bar 402. The zero point of the scale mark 4021 is coplanar with the reference plane of the positioning block 3051. The positioning block 3051, in conjunction with the scale mark 4021, positions the workpiece. The embedded strain gauge sensor can detect the workpiece clamping stress. Through the combined use of the positioning block 3051 and the scale mark 4021, the accuracy of workpiece positioning is improved. The embedded strain gauge sensor in the positioning block 3051 is used to detect the workpiece clamping stress, allowing the first pressure bar 305 and the second pressure bar 402 to adjust the clamping state in a timely manner, avoiding the impact on welding quality due to excessive or insufficient clamping force.

[0041] The movable pressure bar assembly 3 includes a movable adjustment motor 301, which is connected to a movable adjustment screw 302. The movable adjustment screw 302 is threadedly connected to a first lifting power component 304. When the movable adjustment motor 301 drives the movable adjustment screw 302 to rotate, the first lifting power component 304 moves along the length direction of the movable adjustment screw 302.

[0042] A movable adjusting screw 302 is parallel to a movable adjusting slide rail 303. The first lifting power component 304 is slidably connected to the movable adjusting slide rail 303, which provides guidance and support for the movement of the first lifting power component 304. The movable pressure bar assembly 3 enables precise adjustment of the position of the first pressure bar 305, and the distance between the first pressure bar 305 and the second pressure bar 402 can be flexibly adjusted according to the size of the workpiece, improving the versatility of the fixture. Simultaneously, the slide rail ensures smooth and accurate movement.

[0043] The first lifting power component 304, the second lifting power component 401, and the third lifting power component 502 are cylinders or electric cylinders, which have the advantages of fast response speed, high control precision, and stable output force, and can accurately realize the lifting action of each component.

[0044] The 4021 scale markings are made using laser etching technology, resulting in clear and wear-resistant markings with an accuracy of ±0.05mm, ensuring the accuracy and reliability of positioning.

[0045] During the work, select a workpiece support base 2 of appropriate specifications according to the welding task requirements, and use bolts to install it on the workbench 1 to ensure a firm connection.

[0046] The workpiece to be welded is carefully placed on the workpiece support base 2. Using the precise placement and positioning plane provided by the base, the workpiece's position is initially determined. Referring to the scale mark 4021, the workpiece is pushed so that one side aligns with the positioning block 3051. Utilizing the cooperation between the positioning block 3051 and the scale mark 4021, the moving adjustment motor 301 drives the moving adjustment screw 302 to rotate. This causes the first lifting power component 304 to move smoothly along the length of the moving adjustment screw 302 on the moving adjustment slide rail 303, thereby adjusting the distance between the first pressure bar 305 and the second pressure bar 402 to fit the actual size of the workpiece to be welded, ensuring the workpiece is in an accurate welding position. The strain gauge sensor embedded in the positioning block 3051 detects the workpiece clamping stress in real time and provides feedback.

[0047] The first lifting power component 304 is activated to drive the first pressure bar 305 to descend. The second lifting power component 401 is activated to drive the second pressure bar 402 to descend and initially press the workpiece. The third lifting power component 502 is activated to drive the pressure block 501 to descend and assist in pressing the workpiece from all sides of the workpiece support base 2 to ensure that the workpiece will not be displaced during the welding process.

[0048] The friction stir welding equipment is turned on, and the clamped workpiece is welded. During the welding process, the worktable 1 remains stable, and the strain gauge sensor embedded in the positioning block 3051 continuously monitors the workpiece clamping stress to ensure the stability of the welding process and the welding quality.

[0049] After welding is completed, the third lifting power component 502, the second lifting power component 401 and the first lifting power component 304 are activated in sequence to raise the pressure block 501, the second pressure bar 402 and the first pressure bar 305, loosen the pressure on the workpiece, and carefully remove the welded workpiece from the workpiece support base 2.

[0050] Clean debris and welding residue from the workpiece support base 2, and inspect all components for damage or wear. If subsequent welding tasks require replacing the workpiece support base 2 with a different specification, use bolts to remove the current base and install a suitable new base. Through this workflow, the friction stir welding fixture can efficiently and accurately complete the workpiece clamping and welding tasks, ensuring welding quality and production efficiency.

[0051] The fixture of this utility model, by setting a first pressure bar 305 and a second pressure bar 402, and setting a positioning block 3051 on the first pressure bar 305 and a scale mark 4021 on the second pressure bar 402, greatly facilitates the placement of workpieces, avoids multiple alignments by personnel and saves a lot of operation time, and ensures that each workpiece can be accurately positioned when it is placed on the workpiece support base 2 in turn.

[0052] The 4021 scale markings facilitate observation of the welding conditions at different welding positions and temperature testing at different welding positions, which is beneficial for subsequent research and analysis.

[0053] By setting the first pressure bar 305 and the second pressure bar 402, a structure combining the calibration rod and pressure bar is achieved, which saves materials and reduces operation time. The first pressure bar 305 and the second pressure bar 402 completely cover the middle part of the workpiece, which greatly improves the flatness and deformation of the workpiece after welding, and holds the workpiece in the same position, thereby ensuring the reliability of experimental parameters and the stability of product quality.

[0054] Finally, it should be noted that the above are merely preferred embodiments of the utility model and are not intended to limit the utility model. Although the utility model has been described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. However, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the utility model should be included within the protection scope of the utility model.

Claims

1. A fixture for friction stir welding, characterized in that, It includes a worktable (1), a workpiece bearing base (2) is provided on the worktable (1), and a movable pressure strip assembly (3) and a scale pressure strip assembly (4) are provided on the workpiece bearing base (2); The scale pressure bar assembly (4) includes a second lifting power component (401), the output end of which is connected to a second pressure bar (402), and the second pressure bar (402) is provided with scale markings (4021). The movable pressure bar assembly (3) includes a first lifting power component (304), the output end of which is connected to a first pressure bar (305), and the distance between the first pressure bar (305) and the second pressure bar (402) is adjustable; A positioning block (3051) is also provided on the side of the first pressure strip (305) near the second pressure strip (402).

2. The fixture for friction stir welding according to claim 1, characterized in that, The first pressure strip (305) and the second pressure strip (402) are arranged in parallel; The zero point of the scale mark (4021) is coplanar with the reference plane of the positioning block (3051).

3. A fixture for friction stir welding according to claim 2, characterized in that, The movable pressure bar assembly (3) includes a movable adjustment motor (301), which is connected to a movable adjustment screw (302). The movable adjustment screw (302) is threadedly connected to a first lifting power component (304). When the movable adjustment motor (301) drives the movable adjustment screw (302) to rotate, the first lifting power component (304) moves along the length direction of the movable adjustment screw (302).

4. A fixture for friction stir welding according to claim 3, characterized in that, The movable adjusting screw (302) is provided with a movable adjusting slide rail (303) in parallel, and the first lifting power component (304) is slidably connected to the movable adjusting slide rail (303).

5. A fixture for friction stir welding according to claim 4, characterized in that, The workpiece support base (2) is connected to the workbench (1) by bolts, and side support blocks (201) are also provided on both sides of the workpiece support base (2).

6. A fixture for friction stir welding according to any one of claims 1 to 5, characterized in that, The workpiece bearing base (2) is provided with a side pressure block assembly (5) around its perimeter; The edge pressing block assembly (5) includes a third lifting power component (502), the output end of which is connected to the pressing block (501), and the pressing block (501) is located directly above the workpiece bearing base (2).

7. A fixture for friction stir welding according to claim 6, characterized in that, The first lifting power component (304), the second lifting power component (401), and the third lifting power component (502) are cylinders or electric cylinders.

8. A fixture for friction stir welding according to any one of claims 1 to 5, characterized in that, The positioning block (3051) has an embedded strain gauge sensor for detecting workpiece clamping stress.

9. A fixture for friction stir welding according to any one of claims 1 to 5, characterized in that, The scale markings (4021) are made using laser etching technology, with a scale accuracy of ±0.05mm.

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