Reducing winding needle for winding lithium battery cell

Abstract

The utility model relates to a lithium battery cell winding reducing winding needle which comprises a needle core and a needle body, a guide rod and a mounting seat are arranged on the needle core in parallel, the mounting seat is fixedly connected with the needle body, the guide rod is arranged between the needle core and the mounting seat in a transmission mode, and the guide rod has the freedom degree of moving in the length direction of the needle core; a slope is convexly arranged on the guide rod towards the direction of the mounting seat, a follow-up rolling shaft is correspondingly arranged on the mounting seat, a guide component and an elastic component which are connected with the needle core are arranged on the mounting seat in the thickness direction, the mounting seat moves along the thickness direction of the needle core under the limitation of the guide component, and the follow-up rolling shaft is always in contact with the slope under the elastic action of the elastic component. And the movement of the guide rod in the length direction is converted into the movement of the mounting seat in the thickness direction. Through mutual cooperation of the guide rod, the mounting base, the guide assembly and the elastic assembly, movement of the guide rod in the length direction is converted into movement of the mounting base and the needle body in the thickness direction, and diameter changing of the winding needle is achieved.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery production technology, and in particular to a variable diameter winding needle for lithium battery cells. Background Technology

[0002] In the manufacturing process of lithium battery cells, the winding machine winds the positive and negative electrode sheets and the separator into a cell according to the requirements. Before winding, the electrode sheets need to undergo coating, rolling, slitting, and sheet making processes in sequence. During the sheet making process, the electrode sheets are mostly cut out of the electrode sheets by laser cutting. Due to the cumulative error during the laser cutting process, the position of the electrode tabs will be different. In addition, the thickness of the electrode sheets will affect the alignment of the electrode tabs during the winding process, which will cause the electrode tabs to fail to meet the quality requirements of the cell, resulting in the scrapping of the cell.

[0003] If the winding needle is designed to have a variable diameter, the winding diameter of the battery cell can be adjusted based on the electrode position detected during electrode feeding, ensuring that the alignment of the positive and negative electrode tabs after winding meets requirements. Currently, the diameter of the winding needle is changed by attaching Teflon to it. This method is time-consuming and labor-intensive, and the adjustment accuracy is uncontrollable. Alternatively, mechanical methods such as linkages are used to control the diameter of the winding needle, but the control accuracy is low, reducing production efficiency and battery cell quality. Utility Model Content

[0004] To address the shortcomings of existing technologies, this utility model provides a variable diameter winding needle for winding lithium battery cells.

[0005] This utility model provides a variable diameter winding needle for lithium battery cells, including a needle core and a needle body. A guide rod and a mounting seat are arranged parallel to each other on the needle core. The mounting seat is fixedly connected to the needle body. The guide rod is driven between the needle core and the mounting seat and has the freedom to move along the length direction of the needle core. The guide rod has a ramp protruding towards the mounting seat. The mounting seat is correspondingly provided with a follower roller. The mounting seat is provided with a guide component and an elastic component connected to the needle core in the thickness direction. The mounting seat moves along the thickness direction of the needle core under the restriction of the guide component. The follower roller is always in contact with the ramp under the elastic force of the elastic component, and converts the movement of the guide rod in the length direction into the movement of the mounting seat in the thickness direction.

[0006] In some embodiments, the needle core is provided with guide grooves on both sides in the thickness direction, the opening of the guide groove is provided with a side cover, the guide rod is elongated, the guide rod moves along the guide groove under the restriction of the side cover, and the mounting base is arranged parallel to the outside of the guide groove.

[0007] In some embodiments, the bottom of the guide groove is provided with a support roller, and the guide rod is provided with a support surface on the side near the needle core, and the support roller makes rolling contact with the support surface.

[0008] In some embodiments, a support column is provided at the bottom of the guide groove towards the mounting base. The support column is higher than the guide rod and cooperates with the side of the mounting base facing the needle core.

[0009] In some embodiments, the guide rod is recessed in the direction away from the mounting base, and the ramp protrudes from the bottom of the transmission groove.

[0010] In some embodiments, the guiding assembly includes a guide post and a guide sleeve. The guide post is vertically fixed on the mounting base, the needle core has a fixing hole through it along the thickness direction, the guide sleeve is fixed in the fixing hole, and the guide post is inserted into the guide sleeve.

[0011] In some embodiments, the elastic assembly includes a connecting rod, a connecting block, and a compression spring. The connecting rod passes through the connecting hole of the needle core and is vertically fixed between the connecting block and the mounting base. The guide rod is provided with a collision part that cooperates with the locking nozzle. The collision part passes through a bayonet between two connecting rods. The needle core is provided with a blind hole on the side away from the mounting base. The connecting block is located outside the blind hole. The compression spring is installed in the blind hole of the needle core and contacts the connecting block.

[0012] In some embodiments, the width of the guide rod collision part is smaller than the width of the guide rod body, the width of the body is larger than the width of the bayonet, a limiting step is provided between the collision part and the body, and the limiting step cooperates with the connecting rod.

[0013] In some embodiments, the other end of the guide rod opposite the collision part is provided with a connecting part, and a pin extends outward from the end of the connecting part. A return spring is sleeved on the pin, and the return spring acts on the connecting part and the back seat of the needle core respectively.

[0014] In some embodiments, the needle core is provided with a plug that mates with the locking nozzle. The plug includes two inserts symmetrically arranged on the end face of the needle core along the width direction of the needle core, forming a mating groove between the two inserts. The end face of the inserts is provided with a conical surface that is inclined toward the mating groove.

[0015] Compared with the prior art, the beneficial effects of this utility model are: by restricting the mounting seat to move only in the thickness direction through the guide component, and by ensuring that the follower roller can always be in contact with the slope through the elastic component, the movement of the guide rod in the length direction is converted into the movement of the mounting seat in the thickness direction, thereby realizing the position adjustment of the needle body in the thickness direction to meet the variable diameter requirements of lithium battery cell winding. Attached Figure Description

[0016] Figure 1 This is an exploded structural diagram of the variable diameter winding needle for winding lithium battery cells according to an embodiment of this application.

[0017] Figure 2 This is a three-dimensional structural diagram of a variable-diameter winding needle for a lithium battery cell, according to an embodiment of this application.

[0018] Figure 3 This is a side view of the variable diameter winding needle for winding lithium battery cells according to an embodiment of this application.

[0019] Figure 4 This is a top view of the variable diameter winding needle for winding lithium battery cells according to an embodiment of this application.

[0020] Figure 5 This is a cross-sectional structural diagram of the variable diameter winding needle for winding lithium battery cells according to an embodiment of this application.

[0021] Figure label:

[0022] 1. Needle core; 11. Guide groove; 12. Support roller; 13. Support column; 14. Fixing hole; 15. Blind hole; 16. Rear seat; 17. Clearance hole;

[0023] 2. Guide rod; 21. Ramp; 22. Support surface; 23. Transmission groove; 24. Collision part; 25. Limiting step; 26. Connecting part; 27. Pin; 28. Return spring; 29. ​​Alternating hole;

[0024] 3. Mounting base; 31. Follower roller;

[0025] 4. Guide assembly; 41. Guide post; 42. Guide sleeve;

[0026] 5. Elastic component; 51. Connecting rod; 52. Connecting block; 53. Compression spring;

[0027] 6. Side cover;

[0028] 7. Insert block; 71. Connecting groove; 72. Conical surface. Detailed Implementation

[0029] The specific embodiments of this utility model are described with reference to the accompanying drawings.

[0030] refer to Figure 1 The figure shows an exploded view of the variable diameter winding needle for lithium battery cells. The needle core 1 is in the middle. Two sets of guide rods 2 and mounting seats 3 are respectively set on the upper and lower sides of the needle core 1. The mounting seats 3 are used to connect with the needle body (not shown in the figure). The needle body is set as a cylinder. The guide rods 2 drive the mounting seats 3 to move radially relative to the needle core 1, thereby changing the diameter of the needle body and the entire winding needle to achieve variable diameter.

[0031] refer to Figures 1 to 5A variable diameter winding needle for lithium battery cells includes a needle core 1 and a needle body. A guide rod 2 and a mounting base 3 are arranged parallel to each other on the needle core 1. The mounting base 3 is fixedly connected to the needle body. The guide rod 2 is driven between the needle core 1 and the mounting base 3 and has the freedom to move along the length direction of the needle core 1. The guide rod 2 has a ramp 21 protruding towards the mounting base 3. The mounting base 3 is correspondingly provided with a follower roller 31. The mounting base 3 is provided with a guide component 4 and an elastic component 5 connected to the needle core 1 in the thickness direction. The mounting base 3 moves along the thickness direction of the needle core 1 under the restriction of the guide component 4. The follower roller 31 is always in contact with the ramp 21 under the elastic force of the elastic component 5 and converts the movement of the guide rod 2 in the length direction into the movement of the mounting base 3 in the thickness direction.

[0032] The lithium battery cell winding variable diameter winding needle of this application restricts the mounting base 3 to move only in the thickness direction through the guide component 4, and ensures that the follower roller 31 can always be in contact with the ramp 21 through the elastic component 5, thereby converting the movement of the guide rod 2 in the length direction into the movement of the mounting base 3 in the thickness direction, realizing the position adjustment of the needle body in the thickness direction to meet the variable diameter requirements of lithium battery cell winding.

[0033] It should be further explained that the guide assembly 4 restricts the mounting seat 3 to move only away from or towards the needle core 1. In the initial state, the guide rod 2 and the mounting seat 3 are reset under the action of the return spring 28 and the compression spring 53, respectively, bringing the mounting seat 3 close to the needle core 1. When the needle insertion operation is performed before winding, the plug of the needle core 1 is inserted into the locking nozzle (not shown in the attached figure) for positioning. The locking nozzle pushes the guide rod 2 to move relative to the needle core 1, squeezing the mounting seat 3 outward to change its diameter. The amount of diameter change is related to the depth of the plug of the needle core 1 inserted into the locking nozzle. The deeper it is inserted into the locking nozzle, the more the guide rod 2 moves relative to the needle core 1, which in turn drives the mounting seat 3 to move outward more. When the winding is completed and the needle needs to be withdrawn, after the plug of the needle core 1 separates from the locking nozzle, the guide rod 2 is reset under the action of the return spring 28, causing the mounting seat 3 to move close to the needle core 1 again.

[0034] To restrict the degrees of freedom of guide rod 2, in this embodiment, reference is made to... Figures 1 to 4 The needle core 1 has guide grooves 11 on both sides in the thickness direction. A side cover 6 is provided at the opening of the guide groove 11. The guide rod 2 is long and narrow. The guide rod 2 moves along the guide groove 11 under the restriction of the side cover 6. The mounting base 3 is arranged parallel to the outside of the guide groove 11.

[0035] Understandably, with this configuration, the side cover 6 is L-shaped and is fixed to the outer wall of the needle core 1 by screws. Part of the side cover 6 extends to the opening of the guide groove 11. The needle core 1 installs the guide rod 2 by opening the guide groove 11. The guide groove 11 is set in a straight line. The side cover 6 at the opening of the guide groove 11 prevents the guide rod 2 from detaching from the opening, thereby ensuring that the guide rod 2 only has the freedom of movement in the length direction of the needle core 1, thus ensuring the stability of the movement of the guide rod 2.

[0036] To reduce the frictional force during the movement of guide rod 2, in this embodiment, reference is made to... Figure 1 and Figure 5 The bottom of the guide groove 11 is provided with a support roller 12, and the guide rod 2 is provided with a support surface 22 on the side near the needle core 1. The support roller 12 and the support surface 22 are in rolling contact.

[0037] Understandably, with this configuration, two support rollers 12 are provided at the bottom of the guide groove 11. The two support rollers 12 are located on both sides of the follower roller 31. The axes of the support rollers 12 and the follower roller 31 are parallel to each other. The two support rollers 12 roll in contact with the support surface 22, which reduces the friction between the guide rod 2 and the needle core 1 when the guide rod 2 moves. The follower roller 31 of the mounting base 3 presses against the guide rod 2 under the action of the elastic component 5, which reduces the contact between the guide rod 2 and the side cover 6, thus reducing the friction between the guide rod 2 and the side cover 6.

[0038] To avoid excessive pressure on the guide rod 2 by the mounting base 3, in this embodiment, reference is made to... Figure 1 , Figure 3 and Figure 5 A support column 13 is provided at the bottom of the guide groove 11 towards the mounting base 3. The support column 13 is higher than the guide rod 2, and the support column 13 cooperates with the side of the mounting base 3 facing the needle core 1.

[0039] Understandably, with this configuration, the support column 13 acts as a limiting structure, restricting the minimum distance between the mounting base 3 and the guide rod 2, ensuring that the mounting base 3 does not excessively press against the guide rod 2, and preventing the guide rod 2 from getting stuck.

[0040] To make the internal structure of the needle coil more compact, in this embodiment, reference is made to... Figure 1 and Figure 5 The guide rod 2 is recessed in the direction away from the mounting base 3, and the ramp 21 is protruding on the bottom of the transmission groove 23.

[0041] Understandably, with this configuration, the guide rod 2 is plate-shaped, and the recessed transmission groove 23 allows the ramp 21 to sink relative to the plane of the guide rod 2. This allows for a smaller distance between the mounting base 3 and the guide rod 2, while also preventing the guide rod 2 from being too thick. The back of the transmission groove 23 intrudes towards the needle core 1, and the needle core 1 allows for clearance by opening clearance holes 17 at appropriate positions. This ensures that the guide rod 2 has sufficient structural strength while making the internal structure of the coiled needle more compact.

[0042] To restrict the degrees of freedom of the mounting base 3, in this embodiment, reference is made to... Figure 1 and Figure 5 The guide assembly 4 includes a guide post 41 and a guide sleeve 42. The guide post 41 is vertically fixed on the mounting base 3. The needle core 1 is provided with a fixing hole 14 through it along the thickness direction. The guide sleeve 42 is fixed in the fixing hole 14 and the guide post 41 is inserted into the guide sleeve 42.

[0043] Understandably, with this configuration, the fixing hole 14 of the needle core 1 and the guide sleeve 42 are interference fit, so that the guide sleeve 42 is stably fixed on the needle core 1. The guide post 41 is fixedly connected to the mounting base 3 by screws. The guide post 41 and the guide sleeve 42 are in sliding contact, so that the mounting base 3 can move relative to the needle core 1 in the thickness direction, ensuring the linearity and stability of the movement of the mounting base 3 in the thickness direction. The guide rod 2 is correspondingly provided with a clearance hole 29. The guide post 41 and the support post 13 are both located in the corresponding clearance hole 29 to avoid interfering with the movement of the guide rod 2.

[0044] To ensure that the follower roller 31 is always in contact with the ramp 21, in this embodiment, reference is made to... Figure 1 and Figure 5 The elastic component 5 includes a connecting rod 51, a connecting block 52, and a compression spring 53. The connecting rod 51 passes through the connecting hole of the needle core 1 and is vertically fixed between the connecting block 52 and the mounting base 3. The guide rod 2 is provided with a collision part 24 that cooperates with the locking nozzle. The collision part 24 passes through the bayonet between the two connecting rods 51. The needle core 1 is provided with a blind hole 15 on the other side away from the mounting base 3. The connecting block 52 is located outside the blind hole 15. The compression spring 53 is installed in the blind hole 15 of the needle core 1 and contacts the connecting block 52.

[0045] Understandably, with this configuration, the elastic force of the compression spring 53 is transmitted to the mounting base 3 through the connecting block 52 and the connecting rod 51, pulling the mounting base 3 towards the needle core 1. The compression spring 53 is always in a compressed state after assembly. The limit of the mounting base 3 being pulled is limited by the support column 13, so that the compression spring 53 always applies force to the mounting base 3, ensuring that the follower roller 31 is always in close contact with the ramp 21 of the guide rod 2. The compression spring 53 is installed in the blind hole 15, and the connecting block 52 on the outside of the blind hole 15 can block the compression spring 53, preventing the compression spring 53 from detaching from the blind hole 15 on its own, thus ensuring structural stability.

[0046] To ensure that guide rod 2 has sufficient space to move, in this embodiment, reference is made to... Figure 1 and Figure 2 The width of the collision part 24 of the guide rod 2 is smaller than the width of the main body of the guide rod 2, and the width of the main body is larger than the width of the bayonet. A limiting step 25 is provided between the collision part 24 and the main body, and the limiting step 25 cooperates with the connecting rod 51.

[0047] Understandably, with this setup, the main body of the guide rod 2 needs to be wide enough to ensure the setup of the ramp 21 structure and the clearance hole 29 structure. The narrower collision part 24 can easily pass through the bayonet. The limiting step 25 between the collision part 24 and the main body can play a limiting role, preventing the guide rod 2 from extending excessively under the action of the return spring 28, and ensuring stable contact between the ramp 21 and the follower roller 31.

[0048] In order to achieve the reset of guide rod 2, in this embodiment, refer to Figures 1 to 5 The other end of the guide rod 2 opposite to the collision part 24 is provided with a connecting part 26. A pin 27 extends outward from the end of the connecting part 26. A return spring 28 is sleeved on the pin 27. The return spring 28 acts on the connecting part 26 and the back seat 16 of the needle core 1 respectively.

[0049] Understandably, with this configuration, the pin 27 is positioned along the length of the guide rod 2, and the return spring 28 sleeved on the pin 27 acts on the connecting part 26 and the needle core 1 rear seat 16, thereby pushing the guide rod 2 to move and reset along the length direction.

[0050] In order to achieve the docking of the pin core 1 and the lock cylinder, in this embodiment, refer to Figure 1 and Figure 2 The needle core 1 is provided with a plug that mates with the locking nozzle. The plug includes two insert blocks 7 symmetrically arranged on the end face of the needle core 1 along the width direction of the needle core 1. A mating groove 71 is formed between the two insert blocks 7. A conical surface 72 inclined towards the mating groove 71 is provided on the end face of the insert block 7.

[0051] It should be further noted that the locking nozzle structure and needle body structure mentioned in the above scheme can refer to the locking nozzle and outer needle structure in an automatic diameter changing structure for coiled needles disclosed in Chinese Utility Model Patent Application No. CN 202323201311.8.

[0052] Understandably, with this setup, the pin core 1 engages with the locking nozzle via the plug, the two plug blocks 7 of the plug are symmetrically arranged along the width direction, and the collision parts 24 of the two guide rods 2 are symmetrically arranged along the length direction, forming a cross-shaped distribution, which makes it more stable when docking with the locking nozzle. The conical surface 72 of the end face of the plug block 7 can better dock and position the locking nozzle.

[0053] In the operation process of this application, when the coiled needle extends, the plug of the needle core 1 contacts the locking nozzle. The coiled needle is supported at both ends by the rear seat 16 and the locking nozzle, ensuring the overall structural rigidity of the coiled needle. The coiled needle extends further, and the locking nozzle contacts the collision part 24 of the guide rod 2. The ramp 21 pushes the mounting seat 3 outward through the follower roller 31. The mounting seat 3 and the needle body move away from the needle core 1. The coiled needle stops moving when it reaches the designated position. The required diameter of the coiled needle is calculated based on the detected position of the electrode tab. After the diameter of the coiled needle is determined, the battery cell is wound. After the battery cell is wound, the coiled needle is withdrawn and retracted. The return spring 28 pushes the guide rod 2 back to the initial position. The mounting seat 3 returns to the direction closer to the needle core 1 under the action of the compression spring 53, so that the diameter of the coiled needle becomes smaller, which facilitates the feeding of the battery cell.

[0054] This application uses the ramp 21 and the follower roller 31 to convert the linear motion of the guide rod 2 in the length direction into the movement of the mounting base 3 in the thickness direction, so as to meet the requirements of the variable diameter of the battery cell winding. Under the constraints and action of the guide component 4 and the elastic component 5, the mounting base 3 can achieve stable and reliable movement.

[0055] The above does not limit the technical scope of this utility model. Any modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this utility model shall still fall within the scope of the technical solution of this utility model.

Claims

1. A lithium battery cell winding diameter-changing winding mandrel, characterized in that, The device includes a needle core and a needle body. A guide rod and a mounting base are arranged parallel to each other on the needle core. The mounting base is fixedly connected to the needle body. The guide rod is driven between the needle core and the mounting base and has the freedom to move along the length direction of the needle core. The guide rod has a ramp protruding towards the mounting base. The mounting base is correspondingly provided with a follower roller. The mounting base is provided with a guide assembly and an elastic assembly connected to the needle core in the thickness direction. The mounting base moves along the thickness direction of the needle core under the restriction of the guide assembly. The follower roller is always in contact with the ramp under the elastic force of the elastic assembly and converts the movement of the guide rod in the length direction into the movement of the mounting base in the thickness direction.

2. The lithium battery cell winding diameter changing winding mandrel of claim 1, wherein, The needle core has guide grooves on both sides in the thickness direction, and a side cover is provided at the opening of the guide groove. The guide rod is long and narrow, and moves along the guide groove under the restriction of the side cover. The mounting base is arranged parallel to the outside of the guide groove.

3. The lithium battery cell winding diameter changing winding mandrel of claim 2, wherein, The bottom of the guide groove is provided with a support roller, and the guide rod is provided with a support surface on the side near the needle core. The support roller makes rolling contact with the support surface.

4. The lithium battery cell winding diameter changing winding mandrel of claim 2, wherein, A support column is provided at the bottom of the guide groove towards the mounting base. The support column is higher than the guide rod, and the support column cooperates with the side of the mounting base facing the needle core.

5. The lithium battery cell winding variable diameter winding mandrel of claim 1, wherein, The guide rod is recessed in the direction away from the mounting base, and the ramp protrudes from the bottom of the transmission groove.

6. The variable diameter winding needle for lithium battery cells according to claim 1, characterized in that, The guiding assembly includes a guide post and a guide sleeve. The guide post is vertically fixed on the mounting base. The needle core has a fixing hole through it along the thickness direction. The guide sleeve is fixed in the fixing hole. The guide post is inserted into the guide sleeve.

7. The variable diameter winding needle for lithium battery cells according to claim 1, characterized in that, The elastic assembly includes a connecting rod, a connecting block, and a compression spring. The connecting rod passes through the connecting hole of the needle core and is vertically fixed between the connecting block and the mounting base. The guide rod is provided with a collision part that cooperates with the locking nozzle. The collision part passes through the bayonet between the two connecting rods. The needle core is provided with a blind hole on the side away from the mounting base. The connecting block is located outside the blind hole. The compression spring is installed in the blind hole of the needle core and contacts the connecting block.

8. The variable diameter winding needle for lithium battery cells according to claim 7, characterized in that, The width of the guide rod collision part is less than the width of the guide rod body, the width of the body is greater than the width of the bayonet, a limiting step is provided between the collision part and the body, and the limiting step cooperates with the connecting rod.

9. The variable diameter winding needle for lithium battery cells according to claim 7, characterized in that, The guide rod is provided with a connecting part at the other end opposite to the collision part. A pin extends outward from the end of the connecting part, and a return spring is sleeved on the pin. The return spring acts on the connecting part and the back seat of the needle core.

10. The variable diameter winding needle for lithium battery cells according to claim 1, characterized in that, The needle core is provided with a plug that mates with the locking nozzle. The plug includes two inserts symmetrically arranged on the end face of the needle core along the width direction of the needle core. A mating groove is formed between the two inserts. A conical surface inclined towards the mating groove is provided on the end face of the insert.

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