Fixture for cap welding

Abstract

This invention provides a fixture for welding caps to the positive electrode of a battery cell. The fixture includes a base plate, a battery cell positioning component, and a cap positioning component. The battery cell positioning component includes a vertical support plate and a horizontal support plate. The vertical support plate is vertically mounted on the base plate. One end of the horizontal support plate is connected to the vertical support plate, and the other end of the horizontal support plate has a first recessed groove for embedding the battery cell. A mounting hole is also provided at the bottom of the first recessed groove, and a magnetic suction element is provided in the mounting hole. The cap positioning component includes a positioning plate, which is mounted on the vertical support plate and positioned above the horizontal support plate. A second recessed groove is provided on the positioning plate corresponding to the cap, and an installation gap is provided between the second recessed groove and the horizontal support plate for installing the cap. This invention, by setting up a base plate, a battery cell positioning component, and a cap positioning component, can achieve precise installation and fixation of the battery cell and cap, resulting in high positioning accuracy and a high welding yield.

Description

Technical Field

[0001] This utility model relates to the field of batteries, and more particularly to a fixture for welding caps. Background Technology

[0002] In today's battery applications, cylindrical cells such as the 18650 are widely used in various products such as barcode scanners, measuring instruments, LED flashlights, and night vision devices due to their excellent performance. In the production process of these cells, spot welding the boss cap to the positive electrode is a crucial and essential step. However, the market currently lacks specialized positioning fixtures for spot welding the positive electrode and boss cap of cylindrical cells such as the 18650. In actual production, manual assistance is often used to position the cap. This method has many drawbacks. Firstly, manual operation makes it difficult to guarantee the accuracy and consistency of positioning each time, leading to deviations in the spot welding position, which in turn affects the cell's performance, such as poor contact, increased resistance, and in severe cases, even short circuits between the positive and negative electrodes, reducing the cell's yield. Secondly, production efficiency is low and cannot meet the demands of large-scale, high-efficiency modern production. Summary of the Invention

[0003] The purpose of this utility model is to provide a fixture for welding caps, so as to solve the problem of deviation in spot welding position caused by the use of manual assistance to position the caps in the prior art.

[0004] To achieve the above objectives, this utility model provides a fixture for welding caps. The fixture is used to weld caps to the positive electrode of a battery cell without a cap. The fixture includes a base plate, a battery cell positioning assembly, and a cap positioning assembly. The battery cell positioning assembly includes a supporting vertical plate and a supporting horizontal plate connected to the supporting vertical plate. The supporting vertical plate is vertically mounted on the base plate. One end of the supporting horizontal plate is connected to the supporting vertical plate, and the other end of the supporting horizontal plate is provided with a first recessed groove for embedding the battery cell. The bottom of the first recessed groove is also provided with a mounting hole, and a magnetic suction element is provided in the mounting hole. The cap positioning assembly includes a positioning plate, which is mounted on the supporting vertical plate and located above the supporting horizontal plate. The positioning plate is provided with a second recessed groove corresponding to the cap, and a mounting gap for installing the cap is provided between the second recessed groove and the supporting horizontal plate.

[0005] Preferably, there are two support plates, which are arranged alternately in the vertical direction so that the battery cell is embedded in the two first recessed grooves.

[0006] Preferably, the two supporting horizontal plates are a first supporting horizontal plate and a second supporting horizontal plate. The first supporting horizontal plate is connected to the bottom of the supporting vertical plate and abuts against the base plate. The second supporting horizontal plate is connected to the upper part of the supporting vertical plate. The positioning plate is installed on the top surface of the supporting vertical plate. The second recessed groove of the positioning plate and the second supporting horizontal plate are provided with the installation gap.

[0007] Preferably, a buffer layer is provided on the part of the first recessed groove that contacts the battery cell.

[0008] Preferably, the battery cell is a cylindrical battery cell, the cap has a boss structure and the cap includes a circular protrusion in the middle and an annular solder pad around the circular protrusion, the first recessed groove is a semi-circular groove corresponding to the cylindrical battery cell, and the second recessed groove is a semi-circular groove corresponding to the circular protrusion.

[0009] Preferably, the distance between the bottom surface of the positioning plate and the base plate is a first distance, the height of the battery cell without the cap is a first height, the difference between the first distance and the first height is a first difference, the thickness of the annular welding sheet is a first thickness, and the difference between the first difference and the first thickness is greater than or equal to 0.4 mm and less than or equal to 0.6 mm.

[0010] Preferably, the positioning plate has a recessed opening on the side away from the supporting vertical plate, and the bottom of the recessed opening is provided with a second recessed groove.

[0011] Preferably, the vertical support plate is connected to the base plate by a first screw, the horizontal support plate is connected to the vertical support plate by a second screw, and the positioning plate is connected to the vertical support plate by a third screw.

[0012] Preferably, the magnetic attractor is a neodymium iron boron magnet.

[0013] Preferably, the base plate, the vertical support plate, and the horizontal support plate are all made of bakelite, and the positioning plate is made of fiberglass.

[0014] Compared with the prior art, the present invention, by setting a base plate, a cell positioning component, and a cap positioning component, can achieve precise installation and fixation of the cell and cap, resulting in high positioning accuracy, high welding yield, and effective improvement in production efficiency. Attached Figure Description

[0015] Figure 1 This is a structural diagram of a fixture used for cap welding according to an embodiment of the present invention, taken from one angle.

[0016] Figure 2This is a structural view of the fixture used for cap welding according to an embodiment of the present invention from another angle.

[0017] Figure 3 This is a structural diagram of the fixture after the battery cell and cap are installed on it according to an embodiment of the present invention, showing one angle.

[0018] Figure 4 This is a structural diagram from another angle of the fixture after the battery cell and cap are installed on it, according to an embodiment of this utility model.

[0019] Figure 5 for Figure 4 Enlarged view of point A in the middle.

[0020] Figure 6 This is an exploded view of the fixture after the battery cell and cap are installed in an embodiment of this utility model.

[0021] Explanation of reference numerals in the attached diagram: 10. Fixture; 1. Base plate; 2. Cell positioning assembly; 21. Support vertical plate; 22. Support horizontal plate; 2201. First support horizontal plate; 2202. Second support horizontal plate; 221. First recessed groove; 222. Mounting hole; 23. Magnetic suction component; 3. Cap positioning assembly; 31. Positioning plate; 311. Second recessed groove; 312. Recessed opening; 32. Installation gap; 41. First screw; 42. Second screw; 43. Third screw; 20. Cell; 30. Cap; 301. Circular protrusion; 302. Annular welding piece. Detailed Implementation

[0022] To explain in detail the technical content, structural features, and effects of this utility model, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0023] like Figures 1 to 6As shown, this utility model embodiment provides a fixture for cap welding. The fixture 10 is used to weld the cap 30 to the positive electrode of the battery cell 20 without the cap 30. The fixture 10 includes a base plate 1, a battery cell positioning assembly 2, and a cap positioning assembly 3. The battery cell positioning assembly 2 includes a supporting vertical plate 21 and a supporting horizontal plate 22 connected to the supporting vertical plate 21. The supporting vertical plate 21 is vertically mounted on the base plate 1. One end of the supporting horizontal plate 22 is connected to the supporting vertical plate 21, and the other end of the supporting horizontal plate 22 is connected to the supporting vertical plate 21. A first recessed groove 221 for embedding the battery cell 20 is provided. The bottom of the first recessed groove 221 is also provided with a mounting hole 222, and a magnetic suction element 23 is provided in the mounting hole 222. The cap positioning assembly 3 includes a positioning plate 31, which is installed on the support vertical plate 21 and is located above the support horizontal plate 22. A second recessed groove 311 is provided on the positioning plate 31 corresponding to the cap 30. An installation gap 32 for installing the cap 30 is provided between the second recessed groove 311 and the support horizontal plate 22. Specifically, the battery cell 20 can be an 18650 battery cell or a 21700 battery cell. The battery cell 20 and the cap 30 can be connected by spot welding. When the fixture 10 is in use, the bottom of the battery cell 20 is placed on the base plate 1 and the battery cell 20 is close to the first recessed groove 221 on the supporting horizontal plate 22. Since the outer shell of the battery cell 20 is usually a steel shell or an aluminum shell, the magnetic attraction of the magnetic attractant 23 can achieve rapid positioning and stable fixation of the battery cell 20. The cap 30 is placed in the second recessed groove 311 through the installation gap 32 and overlaps on the positive electrode of the battery cell 20. The precise fit between the second recessed groove 311 and the cap 30 achieves a complete fit of the cap 30, making it unable to move left or right. During spot welding, the welding pin completes precise spot welding on the cap 30. Therefore, the fixture 10 of this utility model embodiment has high positioning accuracy and effectively improves production efficiency. In addition, assembly holes and positioning marks can be set on the surface of the base plate 1 to adapt to the installation of production line equipment.

[0024] This utility model embodiment, by setting a base plate 1, a cell positioning component 2, and a cap positioning component 3, can achieve precise installation and fixation of the cell 20 and the cap 30. The positioning accuracy of the cell 20 and the cap 30 is high, the welding yield is high, and the production efficiency can be effectively improved.

[0025] In this embodiment of the utility model, such as Figures 1 to 6 As shown, there are two support horizontal plates 22, which are arranged alternately in the vertical direction so that the battery cell 20 is embedded in the two first recessed grooves 221. Specifically, the two support horizontal plates 22 limit the battery cell 20 to ensure the stability of the fixture 10 in limiting the battery cell 20. Of course, there can also be only one support horizontal plate 22, as long as the thickness of the support horizontal plate 22 is thick enough to stably support the battery cell 20. In addition, there can also be three or more support horizontal plates 22, depending on the actual needs such as the size of the battery cell 20.

[0026] In this embodiment of the utility model, the two supporting horizontal plates 22 are a first supporting horizontal plate 2201 and a second supporting horizontal plate 2202. The first supporting horizontal plate 2201 is connected to the bottom of the supporting vertical plate 21 and abuts against the base plate 1. The second supporting horizontal plate 2202 is connected to the upper part of the supporting vertical plate 21. A positioning plate 31 is installed on the top surface of the supporting vertical plate 21. An installation gap 32 is provided between the second recessed groove 311 of the positioning plate 31 and the second supporting horizontal plate 2202. Specifically, as shown... Figures 1 to 6 As shown, the first support plate 2201 is abutted against the base plate 1, making the installation of the first support plate 2201 more stable. The upper and lower ends of the battery cell 20 are supported by the first support plate 2201 and the second support plate 2202, resulting in better support.

[0027] In this embodiment of the invention, a buffer layer is provided at the contact point between the first recessed groove 221 and the battery cell 20. Specifically, the buffer layer can be a silicone elastic buffer layer with a thickness of 1 mm. By providing the buffer layer, hard contact between the first recessed groove 221 and the battery cell 20 can be avoided, preventing the fixture 10 from scratching the outer surface of the battery cell 20, protecting the surface and structural integrity of the battery cell 20, and reducing damage to the appearance and performance of the battery cell 20.

[0028] In this embodiment of the utility model, such as Figures 4 to 6 As shown, the battery cell 20 is a cylindrical battery cell, and the cap 30 has a boss structure. The cap 30 includes a circular protrusion 301 located in the middle and an annular welding piece 302 arranged around the circular protrusion 301. The first recessed groove 221 is a semi-circular groove arranged on the outer surface of the cylindrical battery cell, and the second recessed groove 311 is a semi-circular groove arranged on the outer surface of the circular protrusion 301. Specifically, the first recessed groove 221 and the second recessed groove 311 can be manufactured by CNC machining. The machining dimensional accuracy of the first recessed groove 221 and the second recessed groove 311 can be controlled within ±0.2 mm, so that the first recessed groove 221 and the second recessed groove 311 accurately match the outer surface of the battery cell 20 and the outer surface of the circular protrusion 301, respectively, and the positioning effect of the battery cell 20 and the cap 30 is better.

[0029] In this embodiment of the utility model, such as Figures 4 to 5As shown, the distance between the bottom surface of the positioning plate 31 and the base plate 1 is the first distance, the height of the cell 20 without the cap 30 is the first height, the difference between the first distance and the first height is the first difference, the thickness of the annular welding sheet 302 is the first thickness, and the difference between the first difference and the first thickness is greater than or equal to 0.4 mm and less than or equal to 0.6 mm. Specifically, the difference between the first difference and the first thickness is the second difference L. The second difference L is the distance between the upper surface of the annular welding piece 302 of the cap 30 and the lower surface of the second recessed groove 311 after the battery cell 20 and the cap 30 are installed in the fixture 10. The second difference L can be 0.5 mm, which makes it easy to place the cap 30 and also limits the cap 30 in the vertical direction. This ensures that the cap 30 will not jump upwards during the welding process. During spot welding, the welding needle passes through the circular protrusion 301 across the cap 30 to perform precise spot welding on the cap 30. Due to the double constraint of the cap 30's vertical and horizontal positioning structure, the cap 30 is guaranteed to have no deviation.

[0030] In this embodiment of the utility model, such as Figure 1 as well as Figure 6 As shown, the positioning plate 31 has a recessed opening 312 recessed inward from the side away from the supporting vertical plate 21, and a second recessed groove 311 is provided at the bottom of the recessed opening 312. Specifically, the recessed opening 312 facilitates the processing of the second recessed groove 311 and increases the operating space for installing the cap 30.

[0031] In this embodiment of the utility model, such as Figures 1 to 6 As shown, the vertical support plate 21 is connected to the base plate 1 by the first screw 41, the horizontal support plate 22 is connected to the vertical support plate 21 by the second screw 42, and the positioning plate 31 is connected to the vertical support plate 21 by the third screw 43. Specifically, the first screw 41 can be a flat-head hexagonal screw, which passes through the bottom surface of the base plate 1 and the supporting vertical plate 21 to connect the base plate 1 and the supporting vertical plate 21. The second screw 42 can be a cup-head hexagonal screw, which passes through the supporting vertical plate 21 from the side away from the supporting horizontal plate 22 to connect the supporting vertical plate 21 and the supporting horizontal plate 22. The third screw 43 can be a flat-head hexagonal screw, which passes through the positioning plate 31 from the side away from the supporting vertical plate 21 to connect the positioning plate 31 and the supporting vertical plate 21. With the setting of the first screw 41, the second screw 42 and the third screw 43, the connection is stable and easy to disassemble and assemble.

[0032] In this embodiment of the utility model, such as Figure 1 as well as Figure 6As shown, the magnetic attractor 23 is a neodymium iron boron magnet. Specifically, the magnetic attractor 23 is cylindrical, with a diameter of 5 mm and a height of 3 mm. Through the first recessed groove 221 and the neodymium iron boron magnet located at the bottom of the first recessed groove 221, the battery cell 20 can be quickly positioned, and the battery cell 20 will not shake during the welding process. The design is ingenious. Of course, in some other specific embodiments, the magnetic attractor 23 can also be a current-carrying coil, etc.

[0033] In this embodiment of the invention, the base plate 1, the supporting vertical plate 21, and the supporting horizontal plate 22 are all made of bakelite, while the positioning plate 31 is made of fiberglass. Specifically, the base plate 1 and the battery cell positioning assembly 2, made of bakelite, provide excellent insulation performance for the fixture 10, while the cap positioning assembly 3, made of fiberglass, provides high mechanical strength for the positioning plate 31. Both bakelite and fiberglass are suitable for use in spot welding environments.

[0034] In this embodiment of the invention, the first recessed groove 221 of the cell positioning component 2, in conjunction with a neodymium iron boron magnet, enables rapid and stable positioning of the cell 20. The second recessed groove 311 of the cap positioning component 3 precisely matches the cap 30, achieving multi-dimensional precise constraint from the cell 20 to the cap 30. The spot welding offset is less than or equal to 0.3mm, significantly reducing the risk of poor soldering and short circuits, and improving the yield of the cell 20 to over 97%. Moreover, the setting of the second recessed groove 311 ensures that the second recessed groove 311 and the circular protrusion 301 of the cap 30 are completely fitted together, completely solving the problem of the cap 30 sliding during spot welding. In addition, the bakelite base plate 1 and the cell positioning component 2 have excellent insulation performance, and the glass fiber cap positioning component 3 has mechanical properties. Both materials are of high strength and suitable for spot welding environments. Furthermore, the support vertical plate 21 and support horizontal plate 22 are connected by cup-head hexagonal screws, and the support vertical plate 21 and base plate 1 are connected by flat-head hexagonal screws. The support vertical plate 21 and positioning plate 31 are also connected by flat-head hexagonal screws, ensuring a stable connection and easy assembly / disassembly. Simultaneously, the silicone elastic buffer layer prevents the fixture 10 from making hard contact with the battery cell 20, avoiding scratches on the outer surface of the battery cell 20 by the fixture 10, protecting the surface and structural integrity of the battery cell 20, and reducing damage to the appearance and performance of the battery cell 20. The fixture 10 in this embodiment has a simple structure and can be quickly integrated into a semi-automatic spot welding production line, reducing spot welding time to 5-7 seconds and improving production efficiency by more than 30%.

[0035] The above-disclosed examples are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent changes made in accordance with the scope of the present utility model application shall still fall within the scope of the present utility model.

Claims

1. A fixture for welding caps, characterized in that: The fixture is used to weld the cap to the positive terminal of a battery cell without a cap. The fixture includes a base plate, a battery cell positioning assembly, and a cap positioning assembly. The battery cell positioning assembly includes a vertical support plate and a horizontal support plate connected to the vertical support plate. The vertical support plate is vertically mounted on the base plate. One end of the horizontal support plate is connected to the vertical support plate, and the other end of the horizontal support plate is provided with a first recessed groove for embedding the battery cell. The bottom of the first recessed groove is also provided with a mounting hole, and a magnetic suction element is provided in the mounting hole. The cap positioning assembly includes a positioning plate, which is mounted on the support vertical plate and located above the support horizontal plate. The positioning plate has a second recessed groove corresponding to the cap, and there is an installation gap between the second recessed groove and the support horizontal plate for installing the cap.

2. The fixture for cap welding as described in claim 1, characterized in that: There are two support plates, which are arranged alternately in the vertical direction so that the battery cell is embedded in the two first recessed grooves.

3. The fixture for cap welding as described in claim 2, characterized in that: The two support horizontal plates are a first support horizontal plate and a second support horizontal plate. The first support horizontal plate is connected to the bottom of the support vertical plate and abuts against the base plate. The second support horizontal plate is connected to the upper part of the support vertical plate. The positioning plate is installed on the top surface of the support vertical plate. The second recessed groove of the positioning plate and the second support horizontal plate are provided with the installation gap.

4. The fixture for cap welding as described in claim 2, characterized in that: A buffer layer is provided at the part of the first recessed groove that contacts the battery cell.

5. The fixture for cap welding as described in claim 1, characterized in that: The battery cell is a cylindrical battery cell, the cap has a boss structure and the cap includes a circular protrusion in the middle and an annular solder pad around the circular protrusion. The first recessed groove is a semi-circular groove corresponding to the cylindrical battery cell, and the second recessed groove is a semi-circular groove corresponding to the circular protrusion.

6. The fixture for cap welding as described in claim 5, characterized in that: The distance between the bottom surface of the positioning plate and the base plate is the first distance, the height of the battery cell without the cap is the first height, the difference between the first distance and the first height is the first difference, the thickness of the annular welding sheet is the first thickness, and the difference between the first difference and the first thickness is greater than or equal to 0.4 mm and less than or equal to 0.6 mm.

7. The fixture for cap welding as described in claim 1, characterized in that: The positioning plate has a recessed opening on the side away from the supporting vertical plate, and the bottom of the recessed opening is provided with a second recessed groove.

8. The fixture for cap welding as described in claim 1, characterized in that: The vertical support plate is connected to the base plate by a first screw, the horizontal support plate is connected to the vertical support plate by a second screw, and the positioning plate is connected to the vertical support plate by a third screw.

9. The fixture for cap welding as described in claim 1, characterized in that: The magnetic attractor is a neodymium iron boron magnet.

10. The fixture for cap welding as described in claim 1, characterized in that: The base plate, the vertical support plate, and the horizontal support plate are all made of bakelite, and the positioning plate is made of fiberglass.

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