A reverse leveling tool for a lithium battery top cover

Abstract

The utility model discloses a kind of lithium battery top cover reverse leveling tool, it is related to new energy battery production equipment field, for solving the problem of unqualified flatness and pole height out-of-tolerance caused by thermal deformation after lithium battery top cover welding. Tool includes pneumatic riveting machine, leveling upper die, leveling lower die, leveling upper die is equipped with the cylindrical convex of polar column adaptation, and leveling lower die is equipped with polar column cylindrical clearance;Pneumatic riveting machine drives upper die to lift, and corrects deformation by protruding and compressing polar column area. Limiting gasket adjustment upper die stroke, cushion block protection polar column, limiting column prevents top cover deviation, limiting sleeve and rod guarantee upper die stable lifting can be additionally provided. The tool leveling precision is high, and adaptability is strong, can protect polar column, improve operating stability and efficiency, effectively improve lithium battery top cover yield, meet the demand of large-scale production.

Description

Technical Field

[0001] This utility model relates to the field of new energy battery production equipment technology, and in particular to a reverse leveling tool for lithium battery top cover. Background Technology

[0002] In the production of new energy lithium batteries, the explosion-proof valve and terminals of the lithium battery top cover need to be fixed to the cover plate by welding. However, the high temperature generated during welding can cause irregular thermal deformation of the top cover, specifically manifested as defects such as the flatness of the cover plate exceeding the acceptable range and inconsistent terminal heights. Such defects can seriously affect the smooth progress of subsequent battery assembly processes, leading to decreased battery sealing performance, poor conductivity stability, and even battery safety hazards.

[0003] To address the aforementioned issues, existing technologies often employ manual tapping or simple clamping for leveling. Manual tapping is not only inefficient but also fails to guarantee leveling accuracy, easily causing secondary damage to the top cover. While simple clamping can achieve a certain degree of leveling, it cannot flexibly adjust pressure and stroke according to the degree of top cover deformation, making it difficult to adapt to different specifications of lithium battery top covers. Furthermore, it lacks effective protection for the terminals, easily leading to overpressure damage. In addition, existing solutions do not precisely limit the placement of the top cover, making it prone to uneven leveling due to top cover misalignment, further increasing product scrap rates and labor costs, failing to meet the demands of large-scale, high-precision production of new energy batteries.

[0004] Therefore, developing a reverse leveling fixture for lithium battery top covers that can precisely adjust the leveling stroke, effectively protect the terminals, and achieve stable positioning of the top cover has become an urgent technical problem to be solved in this field. Utility Model Content

[0005] To address the technical problems existing in the background art, this utility model proposes a reverse leveling fixture for lithium battery top covers.

[0006] This utility model proposes a reverse flattening fixture for lithium battery top cover, including a pneumatic riveting machine, a flattening upper mold, and a flattening lower mold;

[0007] The size of the leveling upper mold is adapted to the size of the lithium battery top cover, and the area of ​​the leveling upper mold corresponding to the terminal post of the lithium battery top cover is provided with a cylindrical protrusion.

[0008] The dimensions of the leveling lower mold are adapted to the dimensions of the lithium battery top cover, and the area of ​​the leveling lower mold corresponding to the lithium battery top cover electrode post is provided with a cylindrical clearance.

[0009] The pneumatic riveting machine is connected to the upper leveling mold and is used to control the lifting and lowering of the upper leveling mold. This causes the cylindrical protrusions of the upper leveling mold to press against the terminal area of ​​the lithium battery top cover placed on the lower leveling mold. This adjusts the thermal deformation of the lithium battery top cover caused by high-temperature welding, ensuring that the flatness of the lithium battery top cover and the height of the terminal are up to standard.

[0010] Preferably, it also includes a set of limiting shims, which are disposed between the pneumatic riveting machine and the upper leveling die, or between the lower leveling die and the worktable, for adjusting the downward stroke of the upper leveling die to adapt to the leveling requirements of lithium battery top covers with different degrees of deformation.

[0011] Preferably, the limiting shim is a replaceable structure, and the thickness of the limiting shim is 0.1mm-5mm. By replacing the limiting shim with different thicknesses, the multi-level adjustment of the upper die pressing stroke can be achieved.

[0012] Preferably, the cylindrical clearance of the lower mold is provided with pads to limit the lithium battery top cover terminals and prevent overvoltage.

[0013] Preferably, the pad is made of wear-resistant metal, and the height of the pad is not greater than the depth of the cylindrical clearance of the leveled lower mold, so as to avoid the pad interfering with the placement of the lithium battery top cover.

[0014] Preferably, the periphery of the leveling lower mold is provided with eight limiting posts, which are used to prevent the lithium battery top cover from being placed crookedly.

[0015] Preferably, the eight limiting posts are evenly distributed around the lower leveling mold, and the height of the limiting posts is greater than the height of the lower leveling mold, so as to achieve full circumferential limiting of the lithium battery top cover.

[0016] Preferably, the upper leveling die has vertical limiting sleeves on both sides, and the lower leveling die has vertical limiting rods on both sides that are adapted to the limiting sleeves. The limiting sleeves can slide along the axial direction of the limiting rods to limit the lifting trajectory of the upper leveling die and improve the stability of the leveling process.

[0017] The reverse leveling fixture for lithium battery top cover proposed in this utility model has the following beneficial effects:

[0018] By precisely matching the cylindrical protrusions of the upper mold and the cylindrical clearance of the lower mold, directional pressure can be applied to the terminal area, effectively correcting welding thermal deformation, ensuring that the flatness of the top cover and the height of the terminal meet the requirements, significantly improving product yield. The replaceable limit shims support multi-level stroke adjustment, which can adapt to lithium battery top covers with different deformation degrees and specifications, reducing tooling change frequency and production costs. The shims can prevent damage to the terminal by overpressure, while the wear-resistant material ensures that the shims are not prone to failure after long-term use, extending the service life of the tooling. The combination of the top cover limit structure and the upper mold guide structure can prevent the top cover from shifting and the upper mold from tilting, ensuring the stability and consistency of the leveling process, making it suitable for mass production.

[0019] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of this utility model;

[0021] Figure 2 This is a schematic diagram of the structure of the leveling upper mold in this utility model;

[0022] Figure 3 This is a schematic diagram of the structure of the leveling lower mold in this utility model;

[0023] The labels in the diagram are as follows: 1. Pneumatic riveting machine; 2. Upper leveling die; 201. Cylindrical protrusion; 3. Lower leveling die; 301. Cylindrical clearance; 4. Limiting post. Detailed Implementation

[0024] The embodiments of this utility model are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar symbols denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0025] like Figures 1-3 The lithium battery top cover reverse leveling fixture shown includes a pneumatic riveting machine 1, a leveling upper mold 2, and a leveling lower mold 3. The structure and connection relationship of each component are as follows:

[0026] Pneumatic riveting machine 1: As a power output component, it is fixedly connected to the leveling upper mold 2. The lifting speed and pressing pressure of the leveling upper mold 2 can be controlled by air pressure regulation to provide a stable pressure source for leveling the top cover.

[0027] The leveling upper mold 2 has an overall size that matches the size of the top cover of the lithium battery to be processed, ensuring that the upper mold can fully cover the area of ​​the top cover to be leveled. At the position of the lithium battery top cover pole corresponding to the leveling upper mold 2, a cylindrical protrusion 201 is integrally formed. The diameter of the protrusion matches the diameter of the pole, which is used to apply precise pressure to the pole area during the leveling process to avoid incomplete leveling caused by pressure dispersion.

[0028] The lower leveling mold 3 is sized to match the upper leveling mold 2 and the lithium battery top cover, serving as the support base for the top cover. In the area of ​​the lower leveling mold 3 corresponding to the lithium battery top cover pole, a cylindrical clearance 301 is provided. The diameter of the clearance is slightly larger than the diameter of the pole, and the depth is designed according to the height of the pole to provide space for the pole and prevent interference between the pole and the lower mold during the leveling process.

[0029] The pneumatic riveting machine 1 drives the leveling upper mold 2 to rise and fall, so that the cylindrical protrusion 201 of the leveling upper mold 2 presses against the lithium battery top cover terminal area placed on the leveling lower mold 3. The reverse pressure is used to correct the thermal deformation of the top cover caused by high temperature welding, and finally ensures that the flatness of the lithium battery top cover and the height of the terminal meet the product quality requirements.

[0030] Limiting gasket assembly

[0031] To accommodate lithium battery caps with varying degrees of deformation, this fixture also includes a set of limiting shims. These shims can be selectively positioned between the pneumatic riveting machine 1 and the upper leveling die 2, or between the lower leveling die 3 and the worktable. By changing the installation position and thickness of the limiting shims, the maximum downward stroke of the upper leveling die 2 can be flexibly adjusted: when the cap deformation is small, a thicker limiting shim is used to shorten the upper die's downward stroke; when the cap deformation is large, a thinner limiting shim is used to increase the upper die's downward stroke, thereby achieving precise leveling of caps with different degrees of deformation.

[0032] Furthermore, the limiting shim adopts a replaceable structure with a thickness range of 0.1mm-5mm. A single thickness shim or a combination of multiple thickness shims can be selected according to actual production needs to achieve multi-level adjustment of the pressing stroke of the upper die 2 and improve the adaptability of the tooling.

[0033] pole protection structure

[0034] Pads are provided at the cylindrical clearances 301 of the lower leveling mold 3. The pads are made of wear-resistant metals such as stainless steel and aluminum alloy, which have good compressive strength and wear resistance, and can withstand the pressure from the upper mold for a long time without easily deforming. The height of the pads does not exceed the depth of the cylindrical clearances 301 of the lower leveling mold 3, ensuring that the pads do not protrude from the bearing surface of the lower mold and avoid interfering with the normal placement of the lithium battery top cover. At the same time, the pads can provide support for the bottom of the terminal post, preventing the terminal post from deforming or being damaged due to excessive pressure during the leveling process, thus achieving effective protection for the terminal post.

[0035] Top cover limiting structure

[0036] Eight limiting posts 4 are fixedly provided around the periphery of the leveling lower mold 3. The eight limiting posts 4 are evenly distributed along the outer periphery of the leveling lower mold 3, such as one at every 45° interval. The height of the limiting posts 4 is greater than the height of the leveling lower mold 3. When the lithium battery top cover is placed on the leveling lower mold 3, the eight limiting posts 4 can limit it from all sides, preventing the top cover from shifting horizontally during the leveling process, ensuring that the cylindrical protrusions 201 of the leveling upper mold 2 can be accurately aligned with the electrode area, and ensuring the consistency of leveling accuracy.

[0037] Upper mold guide structure

[0038] To further improve the stability of the leveling upper mold 2 during its lifting process, vertical limiting sleeves are symmetrically arranged on both sides of the leveling upper mold 2, and vertical limiting rods are correspondingly arranged on both sides of the leveling lower mold 3. The inner diameter of the limiting sleeves matches the outer diameter of the limiting rods, and the limiting sleeves can slide along the axial direction of the limiting rods. When the pneumatic riveting machine 1 drives the leveling upper mold 2 to lift, the cooperation between the limiting sleeves and the limiting rods can limit the lifting trajectory of the leveling upper mold 2, preventing the upper mold from tilting or shifting, ensuring that the downward pressure of the upper mold is evenly applied to the top cover, and improving the leveling effect.

[0039] In this embodiment, during operation:

[0040] This embodiment is for a standard lithium battery top cover (with 2 terminals and a top cover size of 150mm × 80mm). The core structure of this tooling (pneumatic riveting machine 1, upper leveling mold 2, and lower leveling mold 3) is used for leveling operations. The steps are as follows:

[0041] Tooling debugging: Fix the lower leveling mold 3 on the workbench to ensure that the lower mold is horizontal; install the pneumatic riveting machine 1 directly above the upper leveling mold 2, adjust the air pressure of the pneumatic riveting machine 1 to 0.4-0.6MPa, and test whether the upper mold can be raised and lowered smoothly.

[0042] Top cover placement: Place the welded lithium battery top cover with the back side facing up on the flattened lower mold 3, aligning the top cover poles with the cylindrical clearance 301 of the lower mold, ensuring that the top cover fits snugly against the edge of the lower mold.

[0043] Leveling operation: Start the pneumatic riveting machine 1, control the leveling upper mold 2 to slowly descend until the cylindrical protrusion 201 of the upper mold contacts the top cover pole area and applies pressure, maintain the pressure for 3-5 seconds, and use the reverse pressure to correct the thermal deformation of the top cover; then control the upper mold to rise, take out the leveled top cover, and complete one leveling process.

[0044] This embodiment addresses the issue of lithium battery top covers with significant deformation. It requires adjusting the stroke using limiting shims and protecting the terminals with pads. The steps are as follows:

[0045] Gasket installation: Based on the deformation test results of the top cover, select a 1mm thick limiting gasket and install it between the pneumatic riveting machine 1 and the leveling upper mold 2 to shorten the maximum downward stroke of the upper mold and avoid excessive pressure.

[0046] Pad installation: Place stainless steel pads at the two cylindrical clearances 301 of the leveled lower mold 3. The height of the pads is 5mm (the clearance depth of the lower mold is 8mm), ensuring that the pads do not protrude from the bearing surface of the lower mold.

[0047] Subsequent steps: Repeat steps 2-3 in Example 1 to complete the leveling of the top cover. At this time, the pad can support the bottom of the pole post to prevent overpressure; the limiting shim can precisely control the upper mold stroke to avoid secondary deformation of the top cover due to excessive pressure.

[0048] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A reverse leveling fixture for lithium battery top covers, characterized in that, Includes a pneumatic riveting machine (1), a leveling upper die (2), and a leveling lower die (3); The size of the flattening upper mold (2) is adapted to the size of the lithium battery top cover, and the area of ​​the flattening upper mold (2) corresponding to the lithium battery top cover pole is provided with a cylindrical protrusion (201). The dimensions of the leveling lower mold (3) are adapted to the dimensions of the lithium battery top cover, and the area of ​​the leveling lower mold (3) corresponding to the lithium battery top cover pole is provided with a cylindrical clearance (301). The pneumatic riveting machine (1) is connected to the leveling upper mold (2) and is used to control the leveling upper mold (2) to lift and lower, so as to drive the cylindrical protrusion (201) of the leveling upper mold (2) to press the lithium battery top cover pole area placed on the leveling lower mold (3).

2. The lithium battery top cover reverse leveling fixture according to claim 1, characterized in that, It also includes a set of limiting shims, which are located between the pneumatic riveting machine (1) and the upper leveling mold (2), or between the lower leveling mold (3) and the worktable, to adjust the downward stroke of the upper leveling mold (2) to adapt to the leveling requirements of lithium battery top covers with different degrees of deformation.

3. The lithium battery top cover reverse leveling fixture according to claim 2, characterized in that, The limiting shim is a replaceable structure with a thickness of 0.1mm-5mm. By replacing the limiting shim with different thicknesses, the multi-stage adjustment of the pressing stroke of the flattening upper mold (2) can be achieved.

4. The lithium battery top cover reverse leveling fixture according to claim 1, characterized in that, The cylindrical clearance (301) of the lower mold is provided with pads to limit the lithium battery top cover poles and prevent overvoltage.

5. The lithium battery top cover reverse leveling fixture according to claim 4, characterized in that, The pad is made of wear-resistant metal, and the height of the pad is not greater than the depth of the cylindrical clearance (301) of the leveling lower mold (3).

6. The lithium battery top cover reverse leveling fixture according to claim 1, characterized in that, The lower leveling mold (3) is provided with eight limiting posts (4) around its perimeter. The limiting posts (4) are used to prevent the top cover of the lithium battery from being placed crookedly.

7. The lithium battery top cover reverse leveling fixture according to claim 6, characterized in that, The eight limiting posts (4) are evenly distributed around the leveling lower mold (3), and the height of the limiting posts (4) is greater than the height of the leveling lower mold (3).

8. The lithium battery top cover reverse leveling fixture according to claim 1, characterized in that, The upper leveling mold (2) has vertical limiting sleeves on both sides, and the lower leveling mold (3) has vertical limiting rods on both sides that are adapted to the limiting sleeves. The limiting sleeves can slide along the axial direction of the limiting rods.

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