Magnetic pulse welding device

Abstract

The utility model provides a magnetic pulse welding device which is used for welding a first workpiece and a second workpiece into a welding piece. The magnetic pulse welding device comprises a mold used for forming a welding piece; and the coil is used for generating a pulsed magnetic field, the coil and the mold are oppositely arranged, and the first workpiece and the second workpiece are contained between the coil and the mold during welding. And the first workpiece and the second workpiece collide and are welded into a welding part under the action of the pulsed magnetic field. The first workpiece and / or the second workpiece move / moves towards the die in the moving direction in the welding process, a surface structure is arranged on the working face of the die and comprises a groove, and the included angle between the side face of the groove and the moving direction is an acute angle. According to the magnetic pulse welding device, the welding speed and the welding quality of workpieces can be improved.

Description

Magnetic pulse welding device Technical Field

[0001] This utility model relates to welding equipment, and more specifically, to a magnetic pulse welding device, which is particularly suitable for welding bipolar plates. Background Technology

[0002] Magnetic pulse welding, an ultra-high-speed impact welding technology, works by using electromagnetic force to join materials through rapid collisions. During the welding process, the magnetic field generated by the coil penetrates the workpiece, inducing eddy currents within it. The magnetic field formed by these eddy currents interacts with the magnetic field generated by the coil, causing the workpieces to accelerate and collide, thus welding them together. This welding technology is characterized by its high welding speed, reaching speeds of several kilometers per second. However, currently, there are no magnetic pulse welding devices suitable for welding products such as bipolar plates.

[0003] Bipolar plates are one of the key components in fuel cell stacks, typically welded together from two monopolar plates, resulting in a large number of weld joints. For mass production, the welding speed of bipolar plates has a significant impact on the production cycle. Even with the latest laser welding technology, welding bipolar plates several meters long still takes tens of seconds, resulting in a relatively long welding cycle and thus low welding efficiency.

[0004] Therefore, there is a need in the art for a welding apparatus that can significantly shorten the welding cycle. Summary of the Invention

[0005] The technical problem to be solved by this invention is to improve the welding speed and welding quality of workpieces.

[0006] To solve the above-mentioned technical problems, this utility model provides a magnetic pulse welding device for welding a first workpiece and a second workpiece into a weldment. The magnetic pulse welding device includes: a mold for forming the weldment; and a coil for generating a pulsed magnetic field, wherein the coil is disposed opposite to the mold, and the first workpiece and the second workpiece are housed between the coil and the mold during welding. The first workpiece and the second workpiece are collided and welded into the weldment under the action of the pulsed magnetic field. During the welding process, the first workpiece and / or the second workpiece move towards the mold along a direction of motion, and the working surface of the mold has a surface structure including a groove, the angle between the side of the groove and the direction of motion being an acute angle.

[0007] According to a preferred embodiment of the present invention, the two sides of the groove have the same angle with the direction of movement.

[0008] According to a preferred embodiment of the present invention, the cross-sectional shape of the groove is an inverted V shape.

[0009] According to a preferred embodiment of the present invention, the number of grooves is multiple.

[0010] According to a preferred embodiment of the present invention, the depths of the plurality of grooves are different.

[0011] According to a preferred embodiment of the present invention, the magnetic pulse welding device includes multiple molds.

[0012] According to a preferred embodiment of the present invention, the surface structures of the plurality of molds are different.

[0013] According to a preferred embodiment of the present invention, the mold has two working surfaces.

[0014] According to a preferred embodiment of the present invention, the first workpiece and the second workpiece are made of different materials.

[0015] According to a preferred embodiment of the present invention, the welded component is a bipolar plate.

[0016] This invention features a grooved surface on the working surface of the mold, with the sides of the groove forming an acute angle with the direction of workpiece movement, thereby ensuring welding quality under high-speed welding. Furthermore, this invention allows for improved process development efficiency and increased compatibility of the welding equipment with different product models by allowing for mold replacement. Attached Figure Description

[0017] To enable those skilled in the art to more fully understand this utility model, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Wherein:

[0018] Figure 1 is a schematic side view of a magnetic pulse welding device according to an embodiment of the present invention;

[0019] Figure 2 is a schematic perspective view of the magnetic pulse welding device shown in Figure 1 before and after the installation of the first and second workpieces.

[0020] Figure 3 is a schematic perspective view of the first and second workpieces before they are welded together using the magnetic pulse welding device shown in Figure 1, wherein the first workpiece has already been formed.

[0021] Figure 4 is a schematic perspective view of the first and second workpieces in Figure 3 before and after they are welded together; and

[0022] Figure 5 is a schematic diagram of the welded joint during the welding process shown in Figure 3. Detailed Implementation

[0023] To make the present invention clearer, a specific embodiment of the present invention will be described in detail below with reference to the accompanying drawings, but the present invention is not limited to the embodiment described below.

[0024] It should be noted that the directional terms used in this article, such as "up" and "down", "top" and "bottom", "left" and "right", are only for the purpose of explaining the structure of the device with reference to the accompanying drawings. The directions indicated are only the approximate directions shown in the accompanying drawings and do not represent the actual direction of use of the product.

[0025] This invention provides a magnetic pulse welding device 1 for welding a first workpiece 21 and a second workpiece 22 together. The two workpieces are, for example, welded as a bipolar plate. While a bipolar plate is a preferred embodiment of the welded component, this invention is not limited thereto; any workpieces that can be welded together by magnetic pulse can be welded using the device of this invention.

[0026] A preferred embodiment of the present invention is described below with reference to the accompanying drawings. As shown in FIG1, the magnetic pulse welding device 1 includes a mold 11 and a coil 12, which are arranged opposite to each other. The space between the mold 11 and the coil 12 can accommodate a first workpiece 21 and a second workpiece 22 to be welded. The coil 12 generates a pulsed magnetic field, providing a power source for the entire welding process. The mold 11 provides positioning, support, and shaping for the workpiece, and as part of the sensor, it can guide and optimize the magnetic field. The mold 11 and the coil 12 are typically respectively housed in a base. The structure of the base is not limited and can be configured according to the structure of the mold and the coil to be accommodated, as well as the motion requirements, etc., and the present invention does not impose any limitations on this. For the sake of brevity, the term "mold" mentioned below does not exclude the base, wiring, etc. associated with the mold, and similarly, the term "coil" mentioned below does not exclude the base, wiring, etc. associated with the coil. One of the mold and the coil is movable, while the other is fixed. Typically, the mold remains fixed to ensure the accuracy of positioning and the stability of the collision path. The first workpiece 21 and the second workpiece 22 to be welded can be fixed in the space between the mold 11 and the coil 12 by a clamp, respectively, for welding. The clamp can be any tool that can perform the clamping function, and this utility model is not limited to this. When the magnetic pulse welding device 1 is running, the coil 13 generates a pulsed magnetic field. This pulsed magnetic field acts on the first workpiece 21, the second workpiece 22 and the mold in the magnetic field environment, causing the first workpiece 21 and the second workpiece 22 to move at high speed towards the mold along the movement direction Y. Through plastic deformation, they collide and fit with the mold 11 to form a shape, and at the same time, the first workpiece 21 and the second workpiece 22 are welded together.

[0027] Figure 2 shows a schematic diagram of the first workpiece 21 and the second workpiece 22 before and after being clamped and fixed onto the magnetic pulse welding device 1 by a fixture. As shown in Figure 2, the first workpiece 21 is fixed near the mold 11, and the second workpiece 22 is fixed below the first workpiece 21, near the coil 12. Preferably, the first workpiece 21 and the second workpiece 22 are vertically aligned. However, depending on the requirements of the welded product, the first and second workpieces may not be aligned. When the magnetic pulse welding device 1 is running, the pulsed magnetic field of the coil 12 acts simultaneously on the first workpiece 21, the second workpiece 22, and the mold 11, inducing eddy currents in the first and second workpieces 21 and 22. These eddy currents interact with the pulsed magnetic field, causing the first and second workpieces to generate large accelerations, thus moving at high speed towards the mold in a certain direction, thereby deforming and fitting into the mold. During this process, the magnetic field of the mold also drives the workpieces to move at high speed. During the forming process, when the two workpieces collide at high speed, the energy generated by the collision causes plastic deformation and atomic diffusion in the collision area, thereby forming a strong weld bond, thus realizing the magnetic pulse welding of the first and second workpieces. This bonding method not only provides high connection strength but also preserves the original physical and chemical properties of the materials. During magnetic pulse welding, the different requirements of various workpieces can be met by controlling the current in the coil.

[0028] Of course, bonding and welding can be performed separately. For example, Figure 3 shows another welding process. As shown in Figure 3, the first workpiece 21 can first be subjected to high-speed impact against the mold 11 and thus bonded together. Then, the second workpiece 22 is subjected to high-speed impact against the already formed first workpiece 21, thereby achieving magnetic pulse welding of the two workpieces. Figure 4 correspondingly shows a schematic diagram of the first workpiece 21 and the second workpiece 22 before and after welding according to the welding process of Figure 3. As can be seen from the figure, the two workpieces (welded parts) are completely bonded together after welding. This is an embodiment of a welded product. Depending on the requirements of the welded product, there can be space between the two workpieces, or the weld joint can be only a single weld seam, as long as the required welding effect of the product is guaranteed.

[0029] The working surface of the mold 11 of the magnetic pulse welding device 1 of this invention has a surface structure, as shown in Figure 3, which includes one or more grooves 110. Referring to Figure 5, which shows details of one of the grooves included in the surface structure, the figure illustrates the collision process of the first workpiece 21 and the second workpiece 22. The angle α between the side 111 of the groove 110 and the movement direction Y of the workpiece is acute. This arrangement of the side 111 of the groove allows the two workpieces to achieve a joint with good welding effect during welding. Compared with existing welding devices using molds with flat working surfaces, the magnetic pulse welding device of this invention achieves better welding results. During magnetic pulse welding, the first workpiece and / or the second workpiece need to collide with the mold at high speed along the movement direction Y. The acute angle between the side 111 of the groove and the movement direction of the workpiece allows the workpiece to undergo appropriate plastic deformation at the moment of collision, thereby assisting in the strong bonding of the workpieces under the action of the magnetic pulse, thus significantly improving the welding effect. Furthermore, the magnetic pulse welding device of this invention achieves a significant increase in welding speed compared to existing technologies such as laser welding, thereby shortening the production cycle.

[0030] The two sides of the groove 110 form the same angle with the direction of movement of the workpiece. This groove structure ensures that the plastic deformation of the workpiece is uniform during welding, thereby achieving better welding quality. More preferably, the two sides form a V-shape, as shown in Figure 4. The two sides 111 of the groove form different angles α with the direction of movement Y. The bottom of the groove 110 can also be flat, as long as the angle between the sides of the groove and the direction of movement is acute. According to this invention, the surface structure of the mold can have only one groove or multiple grooves. The multiple grooves 110 can be different from each other or partially different. The width and depth of the multiple grooves 110 are not limited, depending on the requirements of the welded product. Figure 4 shows an embodiment of the welded part of this invention. The welded part is a bipolar plate. As shown in Figure 4, the welded part has multiple bends, some of which are connected to each other, and the heights of these bends are not exactly the same. The structure of the welded part reflects the surface structure of the corresponding mold, that is, the depth of the multiple grooves 110 in the surface structure may be different, the angle between the side and the direction of movement may be different, and the multiple grooves 110 may be spaced apart.

[0031] The first workpiece 21 is fixed facing the working surface of the mold 11 during welding. A mold 11 is not limited to having only one working surface; for example, the mold 11 shown in Figure 3 has two working surfaces. The surface structures of the two working surfaces can be different to accommodate different types of welded products.

[0032] This invention relates to a magnetic pulse welding device that can include multiple molds. Each working surface of each mold can have a different surface structure to adapt to the needs of different welding products. This allows for mold replacement based on product requirements, thereby improving product development efficiency and compatibility. Furthermore, each mold can have more than one working surface. As shown in Figure 3, both opposite surfaces of the mold 11 are working surfaces, thus allowing for the adaptation of more products with fewer molds compared to a mold having only one working surface.

[0033] The first and second workpieces of this invention are made of conductive materials, preferably metallic materials with good conductivity, such as titanium alloys, aluminum alloys, magnesium alloys, and stainless steel. These materials have good conductivity and generate a large electromagnetic force under the same conditions, thus facilitating the magnetic pulse welding process. Furthermore, these materials possess a certain degree of plasticity during welding, which is beneficial for deformation upon impact, thereby improving the welding quality of the magnetic pulse welded joint. According to a preferred embodiment of this invention, the first and second workpieces are made of different materials, preferably different metals. Since magnetic pulse welding can achieve welding between different metals without high temperatures, it can ensure a reliable weld joint while maintaining the original properties of the materials. The mold material of this invention is, for example, oxygen-free copper, carbon steel, alloy steel, or titanium alloy, to withstand the electromagnetic force generated during the magnetic pulse welding process while maintaining mechanical strength.

[0034] This invention utilizes magnetic pulse welding, thus significantly improving welding speed and quality compared to existing laser welding technologies. The magnetic pulse welding device of this invention ensures the quality of the weld joint by setting a special surface structure on the working surface of the mold. Compared to the planar working surface of the mold, this invention significantly improves the weld quality by making the sides of the grooves on the working surface of the mold form acute angles with respect to the direction of workpiece movement. Furthermore, this invention's magnetic pulse welding device has multiple molds, each with a different surface structure on its working surface. This allows for mold replacement, improving process development efficiency and enhancing the compatibility of the magnetic pulse welding device with different products.

[0035] The specific embodiments described above are for illustrative purposes only and are not intended to limit the scope of this utility model. Those skilled in the art can make various modifications and variations without departing from the inventive concept of this utility model, and all equivalent technical solutions fall within the protection scope of this utility model. The protection scope of this utility model is defined by the appended claims.

Claims

1. A magnetic pulse welding device (1) for welding a first workpiece (21) and a second workpiece (22) into a weldment, characterized in that, The magnetic pulse welding device (1) includes: a mold (11) for forming the weldment; and a coil (12) for generating a pulsed magnetic field, wherein the coil (12) is disposed opposite to the mold (11), and the first workpiece (21) and the second workpiece (22) are housed between the coil (12) and the mold (11) during welding; the first workpiece (21) and the second workpiece (22) are collided and welded into the weldment under the action of the pulsed magnetic field, wherein the first workpiece (21) and / or the second workpiece (22) move toward the mold (11) along a movement direction during the welding process, and the working surface of the mold (11) is provided with a surface structure, the surface structure including a groove, and the angle between the side (111) of the groove and the movement direction is an acute angle.

2. The magnetic pulse welding device (1) according to claim 1, characterized in that, The two sides (111) of the groove have the same angle with the direction of movement.

3. The magnetic pulse welding device (1) according to claim 2, characterized in that, The groove has an inverted V-shaped cross-section.

4. The magnetic pulse welding device (1) according to claim 1, characterized in that, The number of grooves is multiple.

5. The magnetic pulse welding device (1) according to claim 4, characterized in that, The depths of the multiple grooves are different.

6. The magnetic pulse welding apparatus (1) according to any one of claims 1 to 5, characterized in that, The magnetic pulse welding device (1) includes multiple molds (11).

7. The magnetic pulse welding apparatus (1) according to claim 6, characterized in that, The surface structures of the plurality of molds (11) are different.

8. The magnetic pulse welding apparatus (1) according to any one of claims 1 to 5, characterized in that, The mold (11) has two working surfaces.

9. The magnetic pulse welding apparatus (1) according to any one of claims 1 to 5, characterized in that, The first workpiece (21) and the second workpiece (22) are made of different materials.

10. The magnetic pulse welding apparatus (1) according to any one of claims 1 to 5, characterized in that, The welded component is a bipolar plate.

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