A power battery top cover positioning and welding device

Abstract

The application relates to the technical field of power battery production, in particular to a power battery top cover positioning and welding device, which comprises a welding table and a machining cover fixedly installed on the top of the welding table, openings are formed in the bottoms of the two sides of the machining cover, clamping mechanisms for positioning the battery top cover are arranged in the interiors of the two openings, heating mechanisms for reducing hydrogen-induced cracks at the welds of the battery top cover are arranged on the inner side walls of the machining cover; first, the extension end of the lifting cylinder is elongated to the longest, so that the lifting plate drives the power battery to ascend to the set position; then, the extension end of the turnover cylinder is elongated to the longest, the roller rolls to push the rotating rod to rotate, so that the electric heating ring is turned over to be directly above the battery top cover; at this time, a gap exists between the electric heating ring and the battery top cover, the welds of the battery top cover are heated by the electric heating ring to eliminate residual stress, and nitrogen gas blown out from the gap between the electric heating ring and the battery top cover is used to accelerate the hydrogen escape speed and reduce the generation of hydrogen-induced cracks.

Description

Technical Field

[0001] This invention relates to the field of power battery manufacturing technology, specifically to a power battery top cover positioning and welding device. Background Technology

[0002] A power battery is a power source that provides power to tools, and it is mainly different from a starter battery used to start a car engine. Among them, the power battery top cover positioning and welding device is a key piece of equipment in the production of power batteries. Its core function is to achieve a sealed connection between the top cover and the battery casing through precise positioning and efficient welding.

[0003] Existing power battery top cover welding equipment uses multiple clamping plates to limit the position of the battery top cover during operation. However, during this limiting process, the multiple clamping plates can obstruct laser welding and affect the efficiency of welding the battery top cover. At the same time, during the welding process, hydrogen may be absorbed at the weld seam, forming hydrogen-induced cracks. Furthermore, the weld seam and heat-affected zone may generate residual stress due to uneven local high-temperature expansion and cooling contraction, which can easily affect the sealing performance of the power battery. Summary of the Invention

[0004] The technical problem that this solution addresses is:

[0005] How to solve the problem that hydrogen may be absorbed at the weld during the welding process of the battery top cover, forming hydrogen-induced cracks, and that residual stress may be generated in the weld and heat-affected zone due to uneven local high temperature expansion and cooling contraction, which may easily affect the sealing performance of the power battery.

[0006] How to solve the problem that multiple clamping plates hinder laser welding and affect the welding efficiency of the battery top cover when the battery top cover position is limited.

[0007] The objective of this invention can be achieved through the following technical solution: a power battery top cover positioning welding device, including a welding table and a processing cover fixedly installed on its top, with openings on both sides of the bottom of the processing cover, and clamping mechanisms for positioning the battery top cover provided inside the two openings, and a heating mechanism for reducing hydrogen-induced cracking at the weld of the battery top cover provided on the inner side wall of the processing cover.

[0008] The heating mechanism includes a mounting plate fixedly connected to the inner wall of the processing cover. The mounting plate is arranged horizontally, and a rotating rod is rotatably mounted on the top of the mounting plate. An electric heating ring is fixedly mounted on the end of the rotating rod away from the mounting plate, and the position of the electric heating ring corresponds to the position of the battery top cover.

[0009] A further technical improvement of the present invention is that: a horizontally arranged tilting cylinder is fixedly installed on the top of the mounting plate, and a roller is rotatably arranged on the extended end of the tilting cylinder, and the roller is rolledly connected to the middle part of the rotating rod.

[0010] A further technical improvement of the present invention is that a sealing cover is fixedly installed on the electric heating ring, and a flexible tube is fixedly connected to the top of the sealing cover, with the input end of the flexible tube penetrating the processing cover.

[0011] A further technical improvement of the present invention is as follows: the center of the front of the rotating rod is fixedly connected to the top of the mounting plate by a tension spring; before opening the laser welding fixture, the gas supply fixture is first opened, so that nitrogen gas flows through the hose and blows out from the sealed cover, squeezing the air in the processing cover out from the two openings, reducing the oxygen content in the processing cover, thereby preventing the weld from contacting oxygen in the air to generate oxides. After completing the laser welding of the battery top cover, the extension end of the lifting cylinder is first controlled to extend from the shortest to the longest, so that the lifting plate drives the power battery to the set position. Then, the extension end of the flipping cylinder is controlled to extend to the longest, and the roller rolls to push the rotating rod to rotate, so that the electric heating ring flips to the top of the battery top cover. At this time, there is a gap between the electric heating ring and the battery top cover. The electric heating ring is turned on to heat the weld of the battery top cover to eliminate residual stress. Then, the nitrogen gas blown out from the gap between the electric heating ring and the battery top cover accelerates the speed of hydrogen gas escape from the weld, reduces the generation of hydrogen-induced cracks, and ensures the sealing of the power battery.

[0012] A further technical improvement of the present invention is that the clamping mechanism includes a clamping cylinder fixedly connected to the top of the welding table, the clamping cylinder is arranged horizontally, and the extended end of the clamping cylinder is fixedly connected to a U-shaped frame for limiting the power battery.

[0013] A further technical improvement of the present invention is that: both ends of the U-shaped frame are fixedly connected to inclined guide plates, and the guide surfaces of the two guide plates are both facing the power battery.

[0014] A further technical improvement of the present invention is as follows: two connecting brackets are fixedly installed on the inner side wall of the U-shaped frame away from the power battery, and positioning rods for limiting the power battery are fixedly connected to the ends of the two connecting brackets away from the U-shaped frame; by controlling the extended ends of the two clamping cylinders to extend from their shortest to their longest length, the two U-shaped frames are brought closer to each other. During this process, the battery top cover is centered and aligned by four guide plates, and then the battery top cover is initially limited by the two U-shaped frames. At the same time, the battery top cover is further limited by four positioning rods, so that the position of the battery top cover is completely in contact with the position of the top of the power battery. At this time, the battery top cover between the two adjacent positioning rods is not... The battery top cover, which was previously obstructed, was now unobstructed between the two contacting guide plates. The robotic arm and laser welding fixture were then activated to perform laser welding on the unobstructed area of ​​the battery top cover. After the welding was completed, the extended ends of the two clamping cylinders were retracted and reset to ensure the top of the battery top cover was unobstructed. The laser welding fixture was then used to perform full-scale welding on the battery top cover. During this process, the battery top cover was first positioned using two U-shaped frames, and then local laser welding was performed on the unobstructed area of ​​the battery top cover to prevent displacement during the laser welding process. Finally, the two U-shaped frames were separated, and the battery top cover was laser welded from all angles to avoid affecting the efficiency of the battery top cover welding.

[0015] A further technical improvement of the present invention is that: a vertically arranged lifting cylinder is fixedly installed at the bottom of the welding table by a support plate, and a groove for positioning the power battery is opened at the top of the welding table. A lifting plate is slidably arranged on the inner wall of the groove, and the extended end of the lifting cylinder moves through the groove and is fixedly connected to the bottom of the lifting plate.

[0016] A further technical improvement of the present invention is that a gas supply fixture for conveying nitrogen is fixedly installed on the outer wall of the processing cover. The gas supply fixture is existing technology, and the output end of the gas supply fixture is fixedly connected to the input end of the hose.

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] In use, before activating the laser welding fixture, the gas supply fixture is activated first, allowing nitrogen gas to flow through a hose and blow out from the sealed cover. This forces air out of the processing cover through two openings, reducing the oxygen content and preventing the weld from contacting oxygen in the air to form oxides. After laser welding of the battery top cover is completed, the extension end of the lifting cylinder is first controlled to extend from its shortest to its longest length, causing the lifting plate to lift the power battery to a set position. Then, the extension end of the tilting cylinder is controlled to extend to its longest length, cooperating with the rollers to rotate the rotating rod, causing the electric heating ring to tilt directly above the battery top cover. At this time, there is a gap between the electric heating ring and the battery top cover. The electric heating ring is activated to heat the weld of the battery top cover, eliminating residual stress. In addition, nitrogen gas blown out from the gap between the electric heating ring and the battery top cover accelerates the escape rate of hydrogen gas from the weld, reducing the generation of hydrogen-induced cracks and ensuring the sealing of the power battery.

[0019] In use, this invention controls the extension ends of the two clamping cylinders to extend from their shortest to their longest length, bringing the two U-shaped frames closer together. During this process, four guide plates center and align the battery top cover, and the two U-shaped frames provide initial positioning of the battery top cover. Simultaneously, four positioning rods provide auxiliary positioning of the battery top cover, ensuring that the position of the battery top cover is completely flush with the top of the power battery. At this point, the battery top cover area between two adjacent positioning rods is not obstructed, nor is the battery top cover area between two contacting guide plates. Then, the robotic arm is activated. Using a laser welding fixture, laser welding is performed on the unobstructed areas of the battery top cover. After welding is completed, the extended ends of two tilting cylinders are retracted and reset to ensure the top of the battery top cover is unobstructed. Then, the laser welding fixture is used to perform full-scale welding on the battery top cover. During this process, the battery top cover is first positioned using two U-shaped frames, and then local laser welding is performed on the unobstructed areas of the battery top cover to prevent displacement during laser welding. Finally, the two U-shaped frames are separated, and the battery top cover is laser welded from all angles to avoid affecting the efficiency of welding the battery top cover. Attached Figure Description

[0020] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0021] Figure 1 This is a three-dimensional schematic diagram of the overall structure of the present invention;

[0022] Figure 2 This is a cross-sectional view of the overall internal structure of the present invention;

[0023] Figure 3 This is a three-dimensional schematic diagram of the heating mechanism structure of the present invention;

[0024] Figure 4 This is a cross-sectional view of the heating mechanism structure of the present invention;

[0025] Figure 5 This is a three-dimensional schematic diagram of the clamping mechanism structure of the present invention;

[0026] Figure 6 For the present invention Figure 5 Enlarged view of the structure at point A in the middle.

[0027] In the diagram: 1. Opening door; 2. Processing cover; 3. Support plate; 4. Lifting cylinder; 5. Welding table; 6. Air supply fixture; 7. Heating mechanism; 8. Robotic arm; 9. Clamping mechanism; 10. Lifting plate; 11. Groove; 12. Opening; 701. Electric heating ring; 702. Rotating rod; 703. Tension spring; 704. Mounting plate; 705. Tilting cylinder; 706. Roller; 707. Hose; 708. Sealing cover; 901. Guide plate; 902. U-shaped frame; 903. Clamping cylinder; 904. Positioning rod; 905. Connecting frame. Detailed Implementation

[0028] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Please see Figures 1-6 As shown, a power battery top cover positioning welding device includes a welding table 5 and a processing cover 2 fixedly installed on its top. Openings 12 are provided on both sides of the bottom of the processing cover 2. Clamping mechanisms 9 for positioning the battery top cover are provided inside the two openings 12. A heating mechanism 7 for reducing hydrogen-induced cracking at the weld of the battery top cover is provided on the inner side wall of the processing cover 2.

[0030] Please see Figure 2 and Figure 3 As shown, the heating mechanism 7 includes a mounting plate 704 fixedly connected to the inner wall of the processing cover 2. The mounting plate 704 is arranged horizontally, and a rotating rod 702 is rotatably arranged on the top of the mounting plate 704. An electric heating ring 701 is fixedly installed at the end of the rotating rod 702 away from the mounting plate 704. The position of the electric heating ring 701 corresponds to the position of the battery top cover.

[0031] Please see Figure 3 and Figure 4 As shown, a horizontally arranged tilting cylinder 705 is fixedly installed on the top of the mounting plate 704. A roller 706 is rotatably arranged at the extended end of the tilting cylinder 705. The roller 706 is rolledly connected to the middle part of the rotating rod 702.

[0032] Please see Figure 3 and Figure 4 As shown, a sealing cover 708 is fixedly installed on the electric heating ring 701. A flexible hose 707 is fixedly connected to the top of the sealing cover 708, and the input end of the flexible hose 707 passes through the processing cover 2.

[0033] Please see Figure 3 As shown, the center of the front of the aforementioned rotating rod 702 is fixedly connected to the top of the mounting plate 704 via a tension spring 703. Before opening the laser welding fixture, the gas supply fixture 6 is first opened, allowing nitrogen gas to flow through the hose 707 and blow out from the sealing cover 708, squeezing the air in the processing cover 2 out through the two openings 12, reducing the oxygen content in the processing cover 2, thereby preventing the weld from contacting oxygen in the air to generate oxides. After completing the laser welding of the battery top cover, the extended end of the lifting cylinder 4 is first controlled to extend from its shortest to its longest length, so that the lifting plate 10... The power battery rises to the set position, and then the extended end of the tilting cylinder 705 is extended to its maximum length. In conjunction with the roller 706, the rotating rod 702 is rotated, causing the electric heating ring 701 to flip to the top of the battery cover. At this time, there is a gap between the electric heating ring 701 and the battery cover. The electric heating ring 701 is turned on to heat the weld of the battery cover, eliminating residual stress. In addition, nitrogen gas blown out from the gap between the electric heating ring 701 and the battery cover accelerates the escape speed of hydrogen gas from the weld, reduces the generation of hydrogen-induced cracks, and ensures the sealing of the power battery.

[0034] Please see Figure 2 and Figure 5 As shown, the clamping mechanism 9 includes a clamping cylinder 903 fixedly connected to the top of the welding table 5. The clamping cylinder 903 is arranged horizontally, and a U-shaped frame 902 for limiting the power battery is fixedly connected to the extended end of the clamping cylinder 903.

[0035] Please see Figure 5 and Figure 6 As shown, both ends of the U-shaped frame 902 are fixedly connected to inclined guide plates 901, and the guide surfaces of the two guide plates 901 are facing the power battery.

[0036] Please see Figure 5 and Figure 6As shown, two connecting brackets 905 are fixedly installed on the inner wall of the U-shaped frame 902 away from the power battery. Positioning rods 904 for limiting the power battery are fixedly connected to the ends of the two connecting brackets 905 away from the U-shaped frame 902. By controlling the extended ends of the two clamping cylinders 903 to extend from their shortest to their longest length, the two U-shaped frames 902 are brought closer together. During this process, the battery top cover is centered and aligned by four guide plates 901, and the battery top cover is initially limited by the two U-shaped frames 902. Simultaneously, the battery top cover is further limited by the four positioning rods 904, ensuring that the position of the battery top cover is completely flush with the top of the power battery. At this point, the battery between the two adjacent positioning rods 904... With the top cover unobstructed and the battery top cover between the two contacting guide plates 901 also unobstructed, the robotic arm 8 and laser welding fixture are activated to perform laser welding on the unobstructed area of ​​the battery top cover. After the welding is completed, the extended ends of the two clamping cylinders 903 are controlled to retract and reset, ensuring that the top of the battery top cover is unobstructed. Then, the laser welding fixture is controlled to perform full-scale welding on the battery top cover. During this process, the two U-shaped frames 902 are used for positioning first, and then local laser welding positioning is performed on the unobstructed area of ​​the battery top cover to prevent displacement during the laser welding process. Finally, the two U-shaped frames 902 are separated to perform all-round laser welding on the battery top cover, avoiding affecting the efficiency of welding the battery top cover.

[0037] Please see Figure 2 As shown, the bottom of the welding table 5 is fixedly installed with a vertically arranged lifting cylinder 4 via a support plate 3, and the top of the welding table 5 is provided with a groove 11 for positioning the power battery. A lifting plate 10 is slidably arranged on the inner wall of the groove 11. The extended end of the lifting cylinder 4 moves through the groove 11 and is fixedly connected to the bottom of the lifting plate 10.

[0038] Please see Figure 2 and Figure 3 As shown, a gas supply fixture 6 for conveying nitrogen is fixedly installed on the outer wall of the processing cover 2. The gas supply fixture 6 is prior art, and the output end of the gas supply fixture 6 is fixedly connected to the input end of the hose 707.

[0039] Please see Figure 2 As shown, a robotic arm 8 is fixedly installed on the top of the inner wall of the processing cover 2. A laser welding fixture for welding the battery top cover is movably installed at the output end of the robotic arm 8. The laser welding fixture is existing technology. An opening and closing door 1 is hinged to the front of the outer wall of the processing cover 2.

[0040] Working principle: When using this invention, firstly, as... Figure 1 and Figure 2As shown, open the opening and closing door 1, place the power battery into the groove 11, position the power battery using the groove 11, then place the battery top cover on top of the power battery, and close the opening and closing door 1 promptly to prevent external air from entering the processing chamber 2 during laser welding, which would affect the efficiency of laser welding; Figure 2 and Figure 5 As shown, by controlling the extended ends of the two clamping cylinders 903 to extend from their shortest to their longest length, the two U-shaped frames 902 are brought closer together. During this process, as... Figure 5 and Figure 6 As shown, four guide plates 901 guide the battery top cover to center it, and two U-shaped frames 902 initially limit its position. Simultaneously, four positioning rods 904 provide auxiliary positioning, ensuring the battery top cover is perfectly aligned with the top of the power battery, guaranteeing the accuracy of laser welding. At this point, the area of ​​the battery top cover between two adjacent positioning rods 904 is unobstructed, and the area between two contacting guide plates 901 is also unobstructed. Then, the robotic arm 8 and the laser welding fixture are activated, and the laser welding fixture precisely performs laser welding on the unobstructed areas of the battery top cover. Figure 5 and Figure 6 As shown, after completing the laser welding at this location, the extended ends of the two clamping cylinders 903 are controlled to retract and reset, ensuring the top of the battery cover is unobstructed. Then, the laser welding fixture is controlled to perform comprehensive laser welding on the battery cover. During this process, the battery cover is first positioned using two U-shaped frames 902, and then localized laser welding is performed on the unobstructed area of ​​the battery cover to prevent displacement during the laser welding process. Finally, the two U-shaped frames 902 are separated, and the battery cover is laser welded from all angles to avoid affecting the efficiency of the welding process. Before activating the laser welding fixture, as shown... Figures 2-4 As shown, first turn on the gas supply fixture 6, so that the nitrogen gas flows through the hose 707 and blows out from the sealing cover 708, forcing the air in the processing cover 2 out through the two openings 12, reducing the oxygen content in the processing cover 2, thereby preventing the weld from coming into contact with oxygen in the air and generating oxides; as Figure 3 and Figure 4As shown, after laser welding of the battery top cover is completed, the extended end of the lifting cylinder 4 is first controlled to extend from its shortest to its longest length, so that the lifting plate 10 drives the power battery to rise to the set position. Then, the extended end of the flipping cylinder 705 is controlled to extend to its longest length, and the roller 706 rolls to push the rotating rod 702 to rotate, so that the electric heating ring 701 flips to the top of the battery top cover. At this time, there is a gap between the electric heating ring 701 and the battery top cover. The electric heating ring 701 is turned on to heat the weld of the battery top cover to eliminate residual stress. In addition, nitrogen gas blown out from the gap between the electric heating ring 701 and the battery top cover accelerates the escape speed of hydrogen gas from the weld, reduces the generation of hydrogen-induced cracks, and ensures the sealing of the power battery.

[0041] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A power battery top cover positioning and welding device, comprising a welding table (5) and a processing cover (2) fixedly installed on its top, characterized in that: The processing cover (2) has openings (12) at the bottom of both sides. The two openings (12) are equipped with clamping mechanisms (9) for positioning the battery top cover. The inner sidewall of the processing cover (2) is equipped with a heating mechanism (7) for reducing hydrogen-induced cracking at the weld of the battery top cover. The heating mechanism (7) includes a mounting plate (704) fixedly connected to the inner wall of the processing cover (2). A rotating rod (702) is rotatably provided on the top of the mounting plate (704). An electric heating ring (701) is fixedly installed at the end of the rotating rod (702) away from the mounting plate (704). The position of the electric heating ring (701) corresponds to the position of the battery top cover. A tilting cylinder (705) is fixedly installed on the top of the mounting plate (704), and both the mounting plate (704) and the tilting cylinder (705) are arranged horizontally. A roller (706) is rotatably provided on the extended end of the tilting cylinder (705), and the roller (706) is rolledly connected to the middle of the rotating rod (702). A sealing cover (708) is fixedly installed on the electric heating ring (701), and a flexible hose (707) is fixedly connected to the top of the sealing cover (708). The input end of the flexible hose (707) passes through the processing cover (2). The center of the front of the rotating rod (702) is fixedly connected to the top of the mounting plate (704) by a tension spring (703); A gas supply fixture (6) for conveying nitrogen is fixedly installed on the outer wall of the processing cover (2). The output end of the gas supply fixture (6) is fixedly connected to the input end of the hose (707). The nitrogen gas flows through the hose (707) and is blown out from inside the sealing cover (708).

2. The power battery top cover positioning and welding device according to claim 1, characterized in that, The clamping mechanism (9) includes a clamping cylinder (903) fixedly connected to the top of the welding table (5). The extended end of the clamping cylinder (903) is fixedly connected to a U-shaped frame (902) for limiting the power battery, and the clamping cylinder (903) is arranged horizontally.

3. The power battery top cover positioning and welding device according to claim 2, characterized in that, Both ends of the U-shaped frame (902) are fixedly connected to inclined guide plates (901), and the guide surfaces of the two guide plates (901) are both facing the power battery.

4. The power battery top cover positioning and welding device according to claim 3, characterized in that, Two connecting brackets (905) are fixedly installed on the inner side wall of the U-shaped frame (902) away from the power battery. The ends of the two connecting brackets (905) away from the U-shaped frame (902) are fixedly connected to positioning rods (904) for limiting the power battery.

5. The power battery top cover positioning and welding device according to claim 1, characterized in that, The bottom of the welding table (5) is fixedly installed with a lifting cylinder (4), and the top of the welding table (5) is provided with a groove (11) for positioning the power battery. The inner wall of the groove (11) is slidably provided with a lifting plate (10). The extended end of the lifting cylinder (4) moves through the groove (11) and is fixedly connected to the bottom of the lifting plate (10).

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