Multi-station coil and tooling for electromagnetic pulse welding of flat workpieces

Abstract

The application discloses a kind of multi-station welding coil and its tooling applied to flat workpiece electromagnetic pulse welding, including multiple parallelly arranged main arms, wherein adjacent main arms are connected together by connecting arm, and the end of the main arm of the edge that is suspended is provided with a bus end, and two bus ends are used to be connected with pulse large current generator to form a loop;Multiple welding positions are sequentially and spaced apart on the main arm along its extension direction, a connecting circuit is provided between adjacent welding positions, and multiple welding positions are connected in series by the connecting circuit, and a main arm is formed;The cross-sectional area of the connecting arm, the connecting circuit and the bus end perpendicular to the current direction is greater than the welding position. It can increase the number of flat metal workpieces welded in a single discharge process, improve the utilization rate of discharge energy, and enhance the adaptability of electromagnetic pulse welding industrial applications.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic pulse welding technology, and more specifically to a multi-station coil and its tooling for electromagnetic pulse welding of flat workpieces. Background Technology

[0002] Electromagnetic pulse welding (EMP) is a solid-state welding technology widely used for joining dissimilar metal workpieces, especially flat workpieces such as copper-aluminum alloy busbars in power battery modules. The welding area is part of the EMP welding discharge circuit and also the site of metal-on-metal collision welding, making it one of the core components of an EMP welding system. Currently, EMP welding areas are typically used only for processing single flat metal workpieces, such as I-type coils, E-type coils, and double H-type coils. These methods are difficult to use for simultaneously welding multiple metal workpieces, resulting in low processing efficiency and low utilization of electromagnetic energy. Summary of the Invention

[0003] This invention aims to solve the technical problems existing in the prior art, and innovatively proposes a multi-station welding coil and its tooling for electromagnetic pulse welding of flat workpieces, which can increase the number of flat metal workpieces welded in a single discharge process, improve the discharge energy utilization rate, and enhance the adaptability of electromagnetic pulse welding to industrial applications.

[0004] To achieve the above-mentioned objective of the present invention, the present invention provides a multi-station coil for electromagnetic pulse welding of flat workpieces, including multiple parallel main arms, wherein adjacent main arms are connected in series by connecting arms, and each of the suspended ends of the edge main arms is provided with a bus terminal, and both of the bus terminals are used to connect with a pulse high current generator to form a circuit;

[0005] The main arm has multiple welding points spaced apart along its extension direction. A connecting circuit is provided between adjacent welding points to connect the multiple welding points in series and form the main arm.

[0006] The cross-sectional area of ​​the connecting arm, connecting circuit, and bus terminal perpendicular to the current direction is larger than that of the welded part.

[0007] In the above scheme: the two bus terminals are respectively provided with a large connection hole and a small connection hole. The large connection hole is used to connect the outer conductor layer of the coaxial cable, and the small connection hole is used to connect the inner conductor layer of the coaxial cable. The two bus terminals are respectively connected to the same coaxial cable through the large connection hole and the small connection hole.

[0008] In the above scheme: the number of main arms is even, the bus terminals are all located on the same side, and the large connection hole and the small connection hole are coaxially arranged to facilitate the passage of coaxial cables.

[0009] In the above solution: the welding part, the connecting circuit, the connecting arm and the bus terminal are all integrally formed by conductors, reducing processing steps and directly casting them into one piece, which can avoid energy consumption caused by secondary connection at the connection point.

[0010] In the above scheme: the connecting arm is arc-shaped.

[0011] This invention also provides an electromagnetic pulse welding fixture for flat workpieces, comprising a base, a plate fixing device, and a fixing back plate arranged sequentially from bottom to top. The top of the base is provided with a coil groove for installing the multi-station coil in the above scheme. The base is provided with a vertically arranged screw along its circumference. The plate fixing device is provided with a through hole corresponding to the screw and is detachably installed on the base through the through hole. The top surface of the plate fixing device is provided with a welding groove corresponding to each welding position. The welding groove is used to place the fly plate and the base plate to be welded. The length of the welding groove is longer than the fly plate and the base plate but less than the sum of the lengths of the fly plate and the base plate, so that the ends of the fly plate and the base plate overlap and are joined together. The welding groove is provided with elastic straps corresponding to the fly plate and the base plate, and the fly plate and the base plate are pressed tightly in the welding groove by the elastic straps.

[0012] The fixed back plate is also provided with a through hole for the screw to pass through, and the plate fixing device and the fixed back plate are locked together on the base by locking nuts. The bottom side of the fixed back plate is provided with a pressing block extending into the welding groove for each welding groove. The pressing block is used to press the base plate and the fly plate.

[0013] In the above scheme: the clamping block only presses on the overlapping part of the fly plate and the base plate. Since the overlapping part is the plate part that is welded, the clamping block only presses on this part, which is reasonable.

[0014] In the above scheme: the welding groove is provided with a pad on one side for raising the substrate, and the area on the other side of the pad is exactly matched with the size of the flyboard.

[0015] In the above scheme: the welding parts of the two adjacent main arms are symmetrically arranged, and the welding grooves are also symmetrically arranged, and the positions of the flyboard and the base plate are arranged in an orderly manner.

[0016] In the above solution: the welding area of ​​the multi-station coil is located directly below the overlapping area of ​​the flyboard and the base plate, and the busbar of the multi-station coil extends beyond the base and downwards to form a boss. Both the large and small connecting holes are formed on the boss. The welding area is precisely located at the overlapping area of ​​the flyboard and the base plate, allowing welding only on the overlapping portion. This reasonable design avoids energy waste.

[0017] In summary, due to the adoption of the above technical solutions, the beneficial effects of this invention are as follows: the cross-sectional areas of the connecting arm, connecting circuit, and bus terminal are all larger than the welding area, thereby reducing the coil resistance and improving the mechanical strength of the coil to prevent deformation. The base is used to fix the welding coil and prevent deformation. The plate fixing device is used for insulation between the welding coil, the base plate, and the fly plate, as well as to determine the placement position and gap of the base plate and fly plate. The base plate and fly plate can be placed in the fixing device in advance, allowing for quick replacement of already welded workpieces during the welding process. The fixing back plate is used to prevent the plate from shifting during the welding process, which could lead to welding failure. Within a single discharge time, the multi-station coil applied to electromagnetic pulse welding of flat workpieces can achieve welding of multiple sets of base plates and fly plates, increasing the number of welded workpieces compared to a single-station welding coil. The plate fixing device facilitates quick replacement of already welded plates. Furthermore, the narrow welding area and wide connecting circuit structure reduce the impact on the discharge current. Attached Figure Description

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0019] Figure 1 This is a perspective view of the multi-station coil of the present invention;

[0020] Figure 2 This is a perspective view of the welding fixture of the present invention;

[0021] Figure 3 This is a cross-sectional view of the welding fixture of the present invention;

[0022] Figure 4 yes Figure 3 Enlarged view of point A in the middle;

[0023] Figure 5 This is a perspective view of the base of the present invention;

[0024] Figure 6 This is a 3D view of a multi-station coil mounted on a base;

[0025] Figure 7 This is a three-dimensional view of the plate fixing device;

[0026] Figure 8 This is a sectional view of the plate fixing device;

[0027] Figure 9 This is a bottom view of the fixed back panel. Detailed Implementation

[0028] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0029] like Figures 1-9 As shown, an electromagnetic pulse welding fixture for flat workpieces includes a base 4, a plate fixing device 6, and a fixing back plate 7 arranged sequentially from bottom to top. The base 4 has vertically arranged screws 4a along its circumference. The plate fixing device 6 and the fixing back plate 7 have through holes corresponding to the screws 4a, allowing them to be detachably installed on the base 4. The plate fixing device 6 and the fixing back plate 7 are locked together on the base 4 by locking nuts.

[0030] The top of the base 4 has a coil groove, and a welding coil is installed in the coil groove.

[0031] The welding coil 5 includes two parallel main arms 1, with adjacent main arms 1 connected in series by a connecting arm 2 bent into an arc shape. Each of the two main arms 1 has a bus terminal 3 at one of its suspended ends, and both bus terminals 3 are used to connect to a pulse high current generator to form a circuit.

[0032] Specifically, one of the bus terminals 3 has two large connecting holes 3a spaced apart on the left and right, which are used to connect the outer conductor layer of the coaxial cable. The other bus terminal 3 has two small connecting holes 3b spaced apart on the left and right, which are used to connect the inner conductor layer of the coaxial cable. The large connecting holes 3a and small connecting holes 3b are coaxially arranged, and the two coaxial cables are connected through a pair of coaxially arranged large connecting holes 3a and small connecting holes 3b, that is, the two coaxial cables are connected in parallel with the pulse high current generator to reduce impedance. The coaxial cable connected in this embodiment is the coaxial cable with publication number CN207704886U, in which the two conductor layers are also the shielding layer and the center conductor, respectively.

[0033] Multiple I-shaped welding parts 1a are arranged sequentially at intervals along the extension direction of the main arm 1. A connecting circuit 1b is provided between adjacent welding parts 1a, and the multiple welding parts 1a are connected in series through the connecting circuit 1b to form the main arm 1.

[0034] The cross-sectional areas of the connecting arm 2, the connecting circuit 1b, and the bus terminal 3, which are perpendicular to the current direction, are all larger than those of the welding part 1a. Both ends of the welding part 1a are provided with arc transition parts.

[0035] The welding part 1a, the connecting circuit 1b, the connecting arm 2 and the bus terminal 3 are all integrally formed by conductors, reducing processing steps and directly casting them into one piece, which can avoid energy consumption caused by secondary connections at the connection points.

[0036] The top surface of the plate fixing device 6 has a welding groove 6a corresponding to each welding position 1a. The welding groove 6a is used to place the fly plate a and the base plate b to be welded. The length of the welding groove 6a is longer than the fly plate a and the base plate b but less than the sum of the lengths of the fly plate a and the base plate b, so that the ends of the fly plate a and the base plate b overlap and are joined together. The welding groove 6a has an elastic strap 6c corresponding to the fly plate a and the base plate b, which presses the fly plate a and the base plate b tightly in the welding groove 6a.

[0037] The bottom side of the fixed back plate 7 is provided with a pressing block 7a that extends into each welding groove 6a. The pressing block 7a is used to press the base plate b and the fly plate a.

[0038] The clamping block 7a only presses on the overlapping part of the fly plate a and the base plate b. Since the overlapping part is the plate part that is to be welded, it is reasonable to only press the clamping block 7a on this part.

[0039] The welding groove 6a has a pad 6b on one side for elevating the substrate b, and the area on the other side of the pad 6b is exactly matched with the size of the flyboard a. The height of the pad is such that the substrate b is located above the flyboard a, and a welding gap is left between the substrate b and the flyboard a. In actual use, the fixing back plate 7 of the pad 6b with different thicknesses can be selected according to the welding requirements, or an external elevating structure can be added to meet the welding requirements.

[0040] The welding points 1a of the two adjacent main arms 1 are symmetrically arranged, and the welding grooves 6a are also symmetrically arranged. The positions of the fly plate a and the base plate b are arranged in an orderly manner.

[0041] Furthermore, the welding portion 1a of the multi-station coil 5 is located directly below the overlapping area of ​​the flyer plate a and the substrate b, and the busbar 3 of the multi-station coil 5 extends beyond the base 4 and downwards to form a boss. Both the large connecting hole 3a and the small connecting hole 3b are located on the boss. The welding portion 1a is located precisely at the overlapping area of ​​the flyer plate a and the substrate b, allowing welding to be performed only on the overlapping part. This reasonable design avoids energy consumption.

[0042] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A multi-station coil for electromagnetic pulse welding of flat workpieces, characterized in that: It includes multiple parallel main arms (1), wherein adjacent main arms (1) are connected in series by connecting arms (2), and each of the suspended ends of the edge main arms (1) is provided with a bus terminal (3), and both of the bus terminals (3) are used to connect with a pulse high current generator to form a circuit; The main arm (1) is provided with a plurality of welding parts (1a) spaced apart along its extension direction. A connecting circuit (1b) is provided between adjacent welding parts (1a). The plurality of welding parts (1a) are connected in series through the connecting circuit (1b) to form the main arm (1). The cross-sectional area of ​​the connecting arm (2), the connecting circuit (1b), and the bus terminal (3) perpendicular to the current direction is larger than that of the welding part (1a). The two bus terminals (3) are respectively provided with a large connection hole (3a) and a small connection hole (3b). The large connection hole (3a) is used to connect the outer conductor layer of the coaxial cable, and the small connection hole (3b) is used to connect the inner conductor layer of the coaxial cable. The two bus terminals (3) are respectively connected to the same coaxial cable through the large connection hole (3a) and the small connection hole (3b).

2. The multi-station coil for electromagnetic pulse welding of flat workpieces according to claim 1, characterized in that: The number of main arms (1) is even, the number of bus terminals (3) are all located on the same side, and the large connection hole (3a) and the small connection hole (3b) are coaxially arranged.

3. The multi-station coil for electromagnetic pulse welding of flat workpieces according to claim 1, characterized in that: The welding part (1a), the connecting circuit (1b), the connecting arm (2) and the bus terminal (3) are all integrally formed by conductors.

4. A multi-station coil for electromagnetic pulse welding of flat workpieces according to claim 3, characterized in that: The connecting arm (2) is arc-shaped.

5. A fixture for electromagnetic pulse welding of flat workpieces, comprising the multi-station coil (5) as described in any one of claims 1 to 4, characterized in that: The device includes a base (4), a plate fixing device (6), and a fixing back plate (7) arranged sequentially from bottom to top. The top of the base (4) is provided with a coil groove for installing the multi-station coil (5) according to any one of claims 1 to 4. The base (4) is provided with a vertically arranged screw (4a) along its circumference. The plate fixing device (6) is provided with a through hole corresponding to the screw (4a) and is detachably installed on the base (4) through the through hole. The top surface of the plate fixing device (6) is provided with a through hole corresponding to each welding part (1a). A welding groove (6a) is provided, which is used to place the flyboard (a) and the base plate (b) to be welded. The length of the welding groove (6a) is longer than the flyboard (a) and the base plate (b) but less than the sum of the lengths of the flyboard (a) and the base plate (b), so that the ends of the flyboard (a) and the base plate (b) overlap and are joined together. The welding groove (6a) is provided with elastic straps (6c) corresponding to the flyboard (a) and the base plate (b), and the flyboard (a) and the base plate (b) are pressed tightly in the welding groove (6a) by the elastic straps (6c). The fixed back plate (7) is also provided with a through hole for the screw (4a) to pass through, and the plate fixing device (6) and the fixed back plate (7) are locked together on the base (4) by locking nuts. The bottom side of the fixed back plate (7) is provided with a pressing block (7a) that extends into the welding groove (6a) for each welding groove (6a). The pressing block (7a) is used to press on the base plate (b) and the fly plate (a).

6. The electromagnetic pulse welding fixture for flat workpieces according to claim 5, characterized in that: The clamping block (7a) only clamps the overlapping part of the flyboard (a) and the base plate (b).

7. The electromagnetic pulse welding fixture for flat workpieces according to claim 5, characterized in that: The welding groove (6a) has a pad (6b) on one side for raising the substrate (b), and the area on the other side of the pad (6b) is exactly matched with the size of the flyboard (a).

8. A welding fixture for electromagnetic pulse welding of flat workpieces according to claim 7, characterized in that: The welding parts (1a) of the two adjacent main arms (1) are symmetrically arranged, and the welding grooves (6a) are also symmetrically arranged.

9. The electromagnetic pulse welding fixture for flat workpieces according to claim 5, characterized in that: Furthermore, the welding part (1a) of the multi-station coil (5) is located directly below the overlapping part of the flyer plate (a) and the base plate (b), and the bus end (3) of the multi-station coil (5) extends out of the base (4) and extends downward to form a boss. The large connecting hole (3a) and the small connecting hole (3b) are both opened on the boss.

Images