Welding jig for assembling power lithium battery pack cap

Abstract

The invention relates to the technical field of welding equipment, and discloses a welding jig for assembling a power lithium battery pack cap, which comprises a fixed base, a rotating seat is movably mounted at the top of the fixed base, a battery holder is fixedly mounted at the top of the rotating seat, and a lifting device positioned on the inner side of the battery holder is movably mounted on the fixed base. An annular supporting device located over the battery holder is arranged at the top of the lifting device and comprises a positioning ring and a driven ring which are fixedly installed at the top end of the lifting device, and a cap pressing device is arranged on the inner side of the driven ring. The rotatable driven ring is arranged over the battery holder, the pressing block connected with the transverse connecting shaft is arranged on the inner side of the driven ring, after the cap is placed on the power lithium battery, the pressing block can be used for moving downwards in time to press the cap, and in the process of transferring the power lithium battery and the cap to a welding part, the welding efficiency is greatly improved. And the situation that the cap moves and is staggered is avoided, and then the welding quality of the power lithium battery pack cap is improved.

Description

Technical Field

[0001] This application relates to the field of welding equipment technology, and in particular to a welding fixture for assembling the cap of a power lithium battery pack. Background Technology

[0002] Welding of the cap for power lithium battery packs is one of the core processes in battery packaging, directly affecting the battery's sealing performance, safety, and lifespan. The cap of the lithium battery achieves complete sealing of the casing through welding and provides electrical connection. Currently, the welding of lithium battery caps is usually done using laser welding. A welding laser beam is used to weld in a circular motion on the outer edge of the cap, forming a complete circle at the welded area. During the welding of power lithium batteries, a fixture is usually used to fix the lithium battery. Then, a robotic arm is used on the loading side to place the lithium battery onto the fixture, and the cap is placed at the center of the top of the lithium battery. The fixture then transfers the power lithium battery and the cap together to the area under the laser welding head, where the laser beam emitted by the laser welding head is used for welding.

[0003] However, existing fixtures only secure the lithium-ion batteries during transfer. Because the caps are lightweight, they are prone to shifting or misaligning during transfer, affecting the welding quality and consequently impacting the overall production yield and increasing production costs. Summary of the Invention

[0004] This application proposes a welding fixture for assembling the cap of a power lithium battery pack. It has the advantage that the lightweight cap is less likely to shift or become displaced during the transfer of the power lithium battery, thus solving the problem that existing fixtures only fix the power lithium battery, which leads to the lightweight cap easily shifting or becoming displaced during the transfer of the power lithium battery.

[0005] To achieve the above objectives, this application adopts the following technical solution: a welding fixture for assembling a power lithium battery pack cap, comprising a fixed base, a rotating seat movably mounted on the top of the fixed base, and a motor for driving the rotating seat to rotate at the bottom of the fixed base. A plurality of battery seats arranged in a circular array are fixedly mounted on the top of the rotating seat. A lifting device located inside the battery seats is movably mounted on the fixed base. A ring-shaped support device is located directly above the battery seats on the top of the lifting device. The ring-shaped support device includes a positioning ring fixedly mounted on the top of the lifting device. A passive ring is mounted on the top of the positioning ring via a plane bearing. A cap-pressing device is located inside the passive ring. The cap-pressing device includes a transverse connecting shaft fixedly connected to the inner wall of the passive ring. A first vertical shaft is located at the end of the transverse connecting shaft away from the inner wall of the passive ring. The axis of the first vertical shaft is on the same straight line as the axis of the passive ring. A second vertical shaft is fixedly connected to the bottom end of the first vertical shaft. A pressing block for pressing down the cap is movably fitted onto the bottom end of the second vertical shaft. During laser welding, the transverse connecting shaft changes position with the rotation of the passive ring relative to the positioning ring.

[0006] Furthermore, the rotating seat has a groove located inside the battery holder. The lifting device includes two movable support shafts movably mounted on the rotating seat. The arrangement of the two movable support shafts allows the movable support shafts, the linkage plate, and the first magnetic block to move stably longitudinally as a whole. The bottom ends of the two movable support shafts extend into the interior of the groove and are fixedly connected to a limiting plate. A first spring is provided between the top of the limiting plate and the top of the inner cavity of the groove. The first spring is movably mounted on the outside of the movable support shaft. The top ends of the two movable support shafts are fixedly installed with a linkage plate. The outer side of the positioning ring is fixedly connected to one side of the linkage plate. Through the elastic force of the first spring, the limiting plate can drive the movable support shafts, the linkage plate, the annular support device, and the cap pressing device to move downward as a whole. Then, the pressure block firmly presses the cap onto the top of the power lithium battery. When the rotating seat rotates to transfer the power lithium battery and the cap, it avoids the cap from moving out of place, which would affect the subsequent welding quality of the lithium battery cap.

[0007] Furthermore, a first magnetic block is fixedly installed at the center of the top of the linkage plate, and two L-shaped support rods are fixedly installed on one side of the top of the fixed base. The two L-shaped support rods are located on the side of the cap feeding, and a mounting plate located directly above the first magnetic block is fixedly installed at one end of the top of the two L-shaped support rods. A first electromagnet is fixedly installed at the bottom of the mounting plate. When the first electromagnet is energized, the magnetic attraction force on the first magnetic block is greater than the elastic force of the first spring. The magnetic attraction force on the first magnetic block generated by the first electromagnet is caused by the first magnetic block to drive the linkage plate, the ring support device and the cap pressing device to move upward as a whole, so that a sufficient gap is reserved between the ring support device and the battery holder, so that the power lithium battery can be inserted into the battery holder and the cap can be placed on the top of the power lithium battery.

[0008] Furthermore, the inner diameter of the upper half of the battery holder decreases uniformly from top to bottom, making it easier for the power lithium battery to be inserted from the top of the battery holder.

[0009] Furthermore, the diameter of the first vertical shaft is smaller than that of the second vertical shaft, and a baffle is fixedly installed at the top of the first vertical shaft. A second spring is provided between the pressure block and the transverse connecting shaft, which is movably fitted on the outside of the second vertical shaft. Through the elastic force of the second spring, when the entire pressure cap device moves downward with the annular support device, the first magnetic block and the linkage plate, the elastic force of the second spring can be used for buffering when the pressure block contacts the cap.

[0010] Furthermore, the pressure block is made of rubber. The design of the rubber pressure block not only allows the pressure block to stably press down on the cap, but also prevents damage to the surface of the cap.

[0011] Furthermore, limiting shafts are fixedly installed on the outer sides of the positioning ring and the passive ring, and the limiting shafts on the positioning ring and the passive ring are connected by rubber bands. A protrusion is fixedly installed on the side of the positioning ring away from the linkage plate. One side of the protrusion is designed with a slope, and a second magnetic block is fixedly installed on the slope of the protrusion. An L-shaped support shaft is fixedly installed on the top of the fixed base, and a second electromagnet is fixedly installed on one side of the top of the L-shaped support shaft. Through the tension of the rubber band, the passive ring and the positioning ring are kept stationary under normal conditions. When welding the power lithium battery cap, the second electromagnet is energized to generate a magnetic repulsion force on the second magnetic block, which pushes the second magnetic block to drive the protrusion, the passive ring, and the transverse connecting shaft to rotate relative to the positioning ring, thereby changing the position of the transverse connecting shaft. This ensures that the welding laser beam can weld in a circular manner on the outer edge of the cap without being blocked by the transverse connecting shaft, thus ensuring the welding quality.

[0012] Furthermore, the bump and the positioning ring are integrally molded, which makes the overall structure of the positioning ring and the passive ring more stable.

[0013] The beneficial effects of this invention are as follows:

[0014] 1. This application provides a welding fixture for assembling a power lithium battery pack cap. By setting a rotatable passive ring directly above the battery holder and a horizontally connected pressure block inside the passive ring, the entire ring support device is raised and lowered with the lifting device, which does not affect the placement of the power lithium battery and the cap. At the same time, after the cap is placed on the power lithium battery, the pressure block can move downward to press down the cap in time. During the process of transferring the power lithium battery and the cap to the welding part, the cap is prevented from shifting or becoming misaligned, thereby improving the welding quality of the power lithium battery pack cap.

[0015] 2. By setting a rotatable passive ring directly above the battery holder, and a pressure block connected by a horizontal coupling inside the passive ring, when welding the cap, the passive ring drives the pressure block to rotate relative to the positioning ring. While the pressure block presses down on the cap, it prevents the cap from shifting during the welding process, thus improving the welding quality. It also adjusts the position of the horizontal coupling to avoid obstructing the laser beam, allowing the welding laser beam to weld in a circular motion on the outer edge of the cap, further improving the welding quality. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort:

[0017] Figure 1 This is a schematic diagram of the structure of the present invention;

[0018] Figure 2 for Figure 1 A schematic diagram of the cross-sectional structure of the fixed base and the rotating seat in the middle;

[0019] Figure 3 for Figure 2 A magnified schematic diagram of the structure at point A;

[0020] Figure 4 for Figure 3 Schematic diagram of the central ring support device;

[0021] Figure 5 for Figure 4 Schematic diagram of the intermediate pressure cap device;

[0022] Figure 6 This is a schematic diagram showing the position of the first vertical axis before welding in this invention;

[0023] Figure 7 This is a schematic diagram showing the state after the position of the first vertical axis changes during the welding process of this invention.

[0024] In the diagram: 1. Fixed base; 2. Rotating seat; 201. Groove; 3. Motor; 4. Battery holder; 5. Lifting device; 501. Movable support shaft; 502. Limiting plate; 503. First spring; 504. Linkage plate; 505. First magnet; 6. L-shaped support rod; 7. Mounting plate; 8. First electromagnet; 9. Annular support device; 901. Positioning ring; 902. Passive ring; 903. Protrusion; 904. Second magnet; 10. Press cap device; 101. Horizontal connecting shaft; 102. First vertical shaft; 103. Second vertical shaft; 104. Press block; 105. Second spring; 106. Baffle; 11. Limiting shaft; 12. Rubber band; 13. L-shaped support shaft; 14. Second electromagnet. Detailed Implementation

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] Examples, such as Figure 1-Figure 2 A welding fixture for assembling a cap for a power lithium battery pack includes a fixed base 1. A rotatable rotating seat 2 is mounted on the top of the fixed base 1 via a plane bearing. The rotating seat 2 is driven to rotate by a motor 3 located at the bottom of the fixed base 1. Several battery holders 4 are fixedly mounted on the top of the fixed base 1. The number of battery holders 4 is not less than two, and the several battery holders 4 are arranged in a circumferential array on the top of the fixed base 1. The power lithium battery is inserted into the battery holder 4 from top to bottom. The inner diameter of the upper half of the battery holder 4 decreases uniformly from top to bottom, which facilitates the insertion of the power lithium battery from the top of the battery holder 4.

[0027] Please see Figure 2-Figure 3The bottom of the rotating seat 2 has the same number of grooves 201 as the battery holder 4, and each groove 201 is located inside each battery holder 4. A lifting device 5 located inside the battery holder 4 is movably mounted on the rotating seat 2. The lifting device 5 includes two movable support shafts 501 movably fitted on the rotating seat 2. The bottom ends of the two movable support shafts 501 extend into the groove 201 and are fixedly connected to a limiting plate 502. A first spring 503 is provided between the top of the limiting plate 502 and the top of the inner cavity of the groove 201. The first spring 503 is movably fitted on the outside of the movable support shaft 501. A linkage plate 504 is fixedly installed at the top of the support shaft 501. A first magnetic block 505 is fixedly installed at the middle of the top of the linkage plate 504. Two L-shaped support rods 6 are fixedly installed on one side of the top of the fixed base 1. The two L-shaped support rods 6 are located on the side of the cap feeding. A mounting plate 7 located directly above the first magnetic block 505 is fixedly installed at one end of the top of the two L-shaped support rods 6. A first electromagnet 8 is fixedly installed at the bottom of the mounting plate 7. When the first electromagnet 8 is energized, the magnetic attraction force on the first magnetic block 505 is greater than the elastic force of the first spring 503, which can cause the first magnetic block 505 to drive the linkage plate 504, the movable support shaft 501 and the limiting plate 502 to move upward as a whole.

[0028] Please see Figure 3-Figure 5A ring support device 9 is fixedly connected to one side of the linkage plate 504. The ring support device 9 includes a positioning ring 901. The top of the positioning ring 901 is mounted to a passive ring 902 via a plane bearing. A pressure cap device 10 is provided in the middle of the passive ring 902. The pressure cap device 10 includes a transverse connecting shaft 101 fixedly connected to the inner wall of the positioning ring 901. A first vertical shaft 102 is movably fitted at the end of the transverse connecting shaft 101 away from the passive ring 902. The axis of the first vertical shaft 102 is on the same straight line as the axis of the passive ring 902. The bottom end of the first vertical shaft 102 is fixed. A second vertical shaft 103 is connected, the diameter of which is larger than that of the first vertical shaft 102. A pressure block 104 is movably fitted at the bottom end of the second vertical shaft 103, and the pressure block 104 can rotate relative to the second vertical shaft 103. The pressure block 104 is made of rubber. A second spring 105 is provided between the pressure block 104 and the transverse connecting shaft 101. The second spring 105 is movably fitted on the outside of the second vertical shaft 103. A baffle 106 is fixedly installed at the top end of the first vertical shaft 102. By controlling the first electromagnet 8 to be energized, a magnetic attraction force is generated on the first magnetic block 505, causing the first... A magnetic block 505 drives the linkage plate 504 and the annular support device 9 to move upward as a whole. After the empty battery holder 4 moves with the rotating seat 2 to the side close to the L-shaped support rod 6, the first electromagnet 8 is energized to generate a magnetic attraction force on the first magnetic block 505. This causes the first magnetic block 505 to drive the linkage plate 504, the annular support device 9, the capping device 10, the movable support shaft 501, and the limiting plate 502 to move upward as a whole. This leaves a sufficient gap between the annular support device 9 and the battery holder 4 so that the power lithium battery can be inserted into the battery holder 4, and the cap can be placed on the moving support shaft 6. At the top of the lithium battery, the first electromagnet 8 is de-energized, and the elastic force of the first spring 503 causes the limiting plate 502 to move the movable support shaft 501, the first magnetic block 505, the ring support device 9 and the cap pressing device 10 downward as a whole, so that the pressing block 104 presses the cap on the top of the lithium battery. Then, when the rotating seat 2 rotates as a whole and the battery holder 4 containing the lithium battery is rotated to the other side for laser welding, the cap can always be stably fixed in the middle of the top of the lithium battery. The placement of the lithium battery and the cap can be controlled by existing robotic arm equipment.

[0029] A limiting shaft 11 is fixedly installed on the outer side of the positioning ring 901 and the passive ring 902, and the limiting shaft 11 on the positioning ring 901 and the limiting shaft 11 on the passive ring 902 are connected by a rubber band 12, which can also be replaced by a tension spring. A protrusion 903 is fixedly installed on the side of the positioning ring 901 away from the linkage plate 504, and the protrusion 903 is integrally formed with the positioning ring 901. One side of the protrusion 903 is designed with a slope, and a second magnetic block 904 is fixedly installed on the slope of the protrusion 903. An L-shaped support shaft 13 is fixedly installed on the top of the fixed base 1. A top of the L-shaped support shaft 13 has a... A second electromagnet 14 is fixedly installed on the side. After the battery holder 4 is rotated from the side where the power lithium battery and the cap are placed to the other side, one end of the second electromagnet 14 faces the side of the second magnetic block 904. When the second electromagnet 14 is energized, the magnetic repulsion force of the second electromagnet 14 on the second magnetic block 904 can push the second magnetic block 904 to drive the protrusion 903 and the passive ring 902 to rotate relative to the positioning ring 901, thereby driving the transverse connecting shaft 101 to rotate. This allows the laser beam to pass through the passive ring 902 and the positioning ring 901 and strike the cap during laser welding of the power lithium battery cap, welding it in a circular motion on the outer edge of the cap. Figure 6 As shown by the dashed circle S (representing the welding area on the cap by the laser beam), by controlling the passive ring 902 to drive the transverse connecting shaft 101 to rotate relative to the positioning ring 901, the transverse connecting shaft 101 is repositioned, i.e., from... Figures 6 to 7 The state shown ensures that the welding laser beam can weld in a circular motion on the outer edge of the cap without being blocked by the transverse coupling 101, thereby ensuring welding quality.

[0030] In use, the motor 3 first drives the rotating seat 2 to rotate, causing the empty battery holder 4 on the rotating seat 2 to rotate to one side of the L-shaped support rod 6. Then, the first electromagnet 8 is energized to generate a magnetic attraction force on the first magnetic block 505, causing the first magnetic block 505 to move the linkage plate 504, the annular support device 9, and the capping device 10 upward as a whole, leaving a sufficient gap between the capping block 104 and the battery holder 4 so that the power lithium battery can be placed into the battery holder 4. The cap is then placed in the middle of the top of the power lithium battery. When the first electromagnet 8 is de-energized, the elastic force of the first spring 503 pushes the limiting plate 502 to drive the movable support shaft 501, the linkage plate 504, and the annular support device. 9 and the cap pressing device 10 move down as a whole, so that the pressing block 104 presses down on the cap. During the process of the motor 3 driving the rotating seat 2 to rotate the battery seat 4 to the other side for laser welding, it is ensured that the cap is stably fixed in the middle of the top of the power lithium battery. Finally, when welding the cap, the laser welding equipment emits a welding laser to weld in a circular motion on the outer edge of the cap. During the process of the welding laser drawing a circle, the second electromagnet 14 is energized by controlling it to generate a magnetic repulsive force on the second magnetic block 904 on the protrusion 903. This pushes the protrusion 903 to drive the passive ring 902 and the transverse connecting shaft 101 to rotate, changing the position of the transverse connecting shaft 101 to avoid the welding laser being blocked.

[0031] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A welding fixture for assembling a cap for a power lithium battery pack, comprising a fixed base, characterized in that, A rotating seat is movably mounted on the top of the fixed base, and a motor for driving the rotating seat to rotate is provided at the bottom of the fixed base. Several battery holders arranged in a circular array are fixedly mounted on the top of the rotating seat. A lifting device located inside the battery holders is movably mounted on the fixed base. An annular support device is provided on the top of the lifting device, directly above the battery holders. The annular support device includes a positioning ring fixedly mounted on the top of the lifting device. A passive ring is mounted on the top of the positioning ring via a plane bearing. A cap-pressing device is provided on the inner side of the passive ring. The cap-pressing device includes a transverse connecting shaft fixedly connected to the inner wall of the passive ring. A first vertical shaft is provided at the end of the transverse connecting shaft away from the inner wall of the passive ring. The axis of the first vertical shaft is on the same straight line as the axis of the passive ring. A second vertical shaft is fixedly connected to the bottom end of the first vertical shaft. A pressure block for pressing down the cap is movably fitted at the bottom end of the second vertical shaft. During laser welding, the transverse connecting shaft changes position with the rotation of the passive ring relative to the positioning ring.

2. The welding fixture for assembling the cap of a power lithium battery pack according to claim 1, characterized in that, The rotating seat has a groove located inside the battery holder. The lifting device includes two movable support shafts movably mounted on the rotating seat. The bottom ends of the two movable support shafts extend into the groove and are fixedly connected to a limiting plate. A first spring is provided between the top of the limiting plate and the top of the groove cavity. The first spring is movably mounted on the outside of the movable support shaft. A linkage plate is fixedly installed at the top of the two movable support shafts. The outside of the positioning ring is fixedly connected to one side of the linkage plate.

3. The welding fixture for assembling the cap of a power lithium battery pack according to claim 2, characterized in that, A first magnetic block is fixedly installed at the center of the top of the linkage plate. Two L-shaped support rods are fixedly installed on one side of the top of the fixed base. The two L-shaped support rods are located on the side of the cap feeding area. A mounting plate located directly above the first magnetic block is fixedly installed at one end of the top of the two L-shaped support rods. A first electromagnet is fixedly installed at the bottom of the mounting plate. When the first electromagnet is energized, the magnetic attraction force on the first magnetic block is greater than the elastic force of the first spring.

4. The welding fixture for assembling the cap of a power lithium battery pack according to claim 1, characterized in that, The inner diameter of the upper half of the battery holder decreases uniformly from top to bottom.

5. The welding fixture for assembling the cap of a power lithium battery pack according to claim 1, characterized in that, The diameter of the first vertical shaft is smaller than that of the second vertical shaft, and a baffle is fixedly installed at the top of the first vertical shaft. A second spring is provided between the pressure block and the transverse connecting shaft, which is movably fitted on the outside of the second vertical shaft.

6. The welding fixture for assembling the cap of a power lithium battery pack according to claim 1, characterized in that, The material of the pressure block is rubber.

7. The welding fixture for assembling the cap of a power lithium battery pack according to claim 1, characterized in that, The positioning ring and the passive ring are respectively fixedly installed with limiting shafts on their outer sides, and the limiting shaft on the positioning ring and the limiting shaft on the passive ring are connected by a rubber band. A protrusion is fixedly installed on the side of the positioning ring away from the linkage plate. One side of the protrusion is designed with a slope, and a second magnetic block is fixedly installed on the slope of the protrusion. An L-shaped support shaft is fixedly installed on the top of the fixed base, and a second electromagnet is fixedly installed on one side of the top of the L-shaped support shaft.

8. The welding fixture for assembling the cap of a power lithium battery pack according to claim 1, characterized in that, The bump and the positioning ring are integrally molded.

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