Formed foil connecting method
By trimming the head and tail of the roll into a specific shape and using a plum blossom hammer to form multiple rows of hammer marks, the problem of easy breakage at the joint of the foil is solved, and stable connection and efficient production are achieved.
Patent Information
- Application Number
- CN202511054329.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-30
- Publication Date
- 2025-10-03
AI Technical Summary
In existing foil splicing methods, the overlapping area is prone to breakage, resulting in production discontinuity and low efficiency.
By trimming the roll head and tail into a specific shape, cleaning and drying the overlapping surface, and using a plum blossom hammer to form multiple rows of hammer marks of different numbers and curvatures, the stress is evenly distributed to ensure the stability of the connection.
The connection strength and expansion performance of the foil joint are improved, which ensures the continuity and stability of production and improves production efficiency.
Smart Images
Figure CN120748930A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of foil splicing, and in particular relates to a method for splicing formed foils. Background Art
[0002] Formed foil is the core raw material for aluminum electrolytic capacitors. Its surface is electrochemically treated to form a nanoscale dielectric oxide film (Al2O3). The uniformity and density of this film directly determine the capacitor's withstand voltage, leakage current, and lifespan. In roll-to-roll continuous production, the length of a single roll of aluminum foil is limited (typically ≤3000m), necessitating splicing to maintain continuous production line operation. Therefore, the splicing process is crucial for production efficiency and product consistency.
[0003] The commonly used foil splicing method is to overlap the tail end of the previous roll of aluminum foil and the head end of the next roll of aluminum foil, and then use a plum blossom hammer or a flat hammer to hammer the overlapping area in sequence to form dense hammer marks in the overlapping area. However, after the foil is spliced using this method, the overlapping area is easily broken when passing through the chemical forming equipment, causing the previous roll of aluminum and the next roll of aluminum to be disconnected, and continuous production cannot be guaranteed. Summary of the Invention
[0004] In view of this, the present invention provides a method for joining formed foils to solve the technical problem in the prior art that the overlapping area is easily broken after joining the foils.
[0005] To achieve the above objectives, this application adopts the following scheme: A method for joining formed foils, comprising the following steps: S10. The front end of the head of the rear roll of foil is trimmed into a curved edge, and the front end of the tail of the front roll of foil is trimmed into a right angle edge, and ensure smooth and burr-free edges; S20 clean and dry the roll head and the roll tail portion of the overlapping surface; S30. The roll head is overlapped above the roll tail, the overlapping area is the overlapping area, and press to smooth the overlapping area; S40. Using a plum hammer to strike the overlap area to complete the front and rear rolled foil joining operation: striking a first number of hammer marks on the curved edge of the roll head to form a first row of hammer marks, wherein the curvature of the first row of hammer marks is consistent with the curvature of the curved front end of the roll head; A second row of hammer marks is struck below the first row of hammer marks, offset from the first row of hammer marks, to form a second row of hammer marks, wherein the second number is smaller than the first number, and the arc of the second row of hammer marks is smaller than that of the first row of hammer marks; The second number of hammer marks are struck below the second row of hammer marks, offset from the second row of hammer marks, to form a third row of hammer marks, wherein the arc of the third row of hammer marks is smaller than that of the second row of hammer marks; A third number of hammer marks are struck below the third row of hammer marks, offset from the third row of hammer marks, to form a fourth row of hammer marks, which are arranged in a straight line.
[0006] Preferably, when "cleaning and drying the overlapping surface of the roll head and the roll tail", the humidity is ensured to be less than 10%.
[0007] Preferably, the length of the overlapping area is 80-100 mm.
[0008] Preferably, the first row of hammer marks is 4-5 mm away from the arc edge.
[0009] Preferably, the step of “striking a first number of hammer marks on the arc-shaped edge of the roll head” includes: sequentially striking a first number of hammer marks from the middle of the arc-shaped edge of the roll head toward both sides.
[0010] Preferably, the second number of hammer marks are struck from left to right below the first row of hammer marks and offset from the first row of hammer marks.
[0011] Preferably, the second number of hammer marks are struck from right to left below the second row of hammer marks and offset from the second row of hammer marks.
[0012] Preferably, the third number of hammer marks are struck in sequence from the middle to both sides below the third row of hammer marks and offset from the third row of hammer marks.
[0013] Preferably, the S40 includes: S41. A first number of hammer marks are struck on the curved edge of the volume head from the middle to the sides to form the first row of hammer marks. S42. Strike a second number of hammer marks below the first row of hammer marks, offset from left to right, to form a second row of hammer marks. S43. Striking the second number of hammer marks below the second row of hammer marks from right to left, offset from the second row of hammer marks, to form a third row of hammer marks; S44. Below the third row of hammer marks, strike a third number of hammer marks from the center outward, offset from the third row of hammer marks, to form a fourth row of hammer marks.
[0014] In the above-mentioned method of joining formed foils, since the curvature of the first row of hammer marks is consistent with the curvature of the curved edge, when subjected to external force, the stress can be evenly transmitted along the curved edge, avoiding stress concentration at the curved edge; the smaller curvature and fewer connection points of the second row of hammer marks enable the stress to be more evenly distributed during the expansion and contraction process, reducing the possibility of local stress concentration leading to fracture; the curvature of the third row of hammer marks is further reduced, which can further refine the stress transfer path, so that the stress can be more evenly distributed in various parts of the roll head; the fourth row of hammer marks is arranged in a straight line, which can adjust the local stress in the area of the right-angle edge near the tail of the roll, so that the stress distribution in the entire overlap area is more balanced. The method provided in the present application realizes a tight and firm connection between two rolls of chemical foil in the overlapping area after a series of operations such as trimming, cleaning, drying and hammering with a plum blossom hammer. The design of multiple rows of hammer marks with different numbers and curvatures makes the overlapping area have good elasticity. When the chemical foil passes through the chemical forming equipment, it can better adapt to the operation and deformation of the equipment, and the overlapping area will not be broken due to expansion and contraction, thereby ensuring the continuity and stability of production, thereby improving the efficiency of the entire chemical foil production process. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 It is a schematic diagram of the roll head and roll tail in the present invention.
[0016] Figure 2 Schematic diagram of the overlapping area in the present invention.
[0017] Figure 3 This is a schematic diagram of foil connection in the present invention.
[0018] Figure 4 It is a partial enlarged view of the foil connection schematic diagram in the present invention.
[0019] In the figure, there is a roll head 100 , a roll tail 200 , an overlapping area 300 , a first row of hammer marks 310 , a second row of hammer marks 320 , a third row of hammer marks 330 , and a fourth row of hammer marks 340 . DETAILED DESCRIPTION
[0020] To facilitate understanding of the present application, a more comprehensive description of the present application will be provided below with reference to the accompanying drawings. Preferred embodiments of the present application will also be described. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present application.
[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0022] Please see Figures 1 to 4 In a specific embodiment, a method for joining formed foils comprises the following steps: S10. The front end of the rear roll of the foil head 100 is trimmed into a curved edge, and the front end of the front roll of the foil tail 200 is trimmed into a right angle edge, and ensure smooth and burr-free edges; S20 cleaning and drying the roll head 100 and the roll tail 200 of the overlapping surface; S30. The roll head 100 is overlapped above the roll tail 200, the overlapping area is the overlapping area 300, and presses to smooth the overlapping area 300; S40 using a plum hammer to hit the overlap area 300, to complete the front and back rolled into foil foil operation: A first number of hammer marks are struck on the curved edge of the roll head 100 to form a first row of hammer marks 310 , wherein the curvature of the first row of hammer marks 310 is consistent with the curvature of the front end of the roll head 100 ; A second number of hammer marks are struck below the first row of hammer marks 310 and offset from the first row of hammer marks 310 to form a second row of hammer marks 320 , wherein the second number is smaller than the first number, and the arc of the second row of hammer marks 320 is smaller than the arc of the first row of hammer marks 310 ; The second number of hammer marks are struck below the second row of hammer marks 320 and offset from the second row of hammer marks 320 to form a third row of hammer marks 330 , wherein the arc of the third row of hammer marks 330 is smaller than that of the second row of hammer marks 320 ; A third number of hammer marks are struck below the third row of hammer marks 330 , offset from the third row of hammer marks 330 , to form a fourth row of hammer marks 340 , which is arranged in a straight line.
[0023] When joining foils, the front end of the next roll of formed foil (100) is first trimmed into an arc. This can be done using a pre-designed arc mold with an arc-shaped edge that meets the required curvature. This arc mold is placed on the roll head (100) and the front end is trimmed along the arc mold to form the arc. This allows for a more uniform stress distribution in the overlap region (300) when subjected to stress. Compared to traditional right-angle or straight-line overlaps, the curved front end can reduce stress concentration and lower the risk of breakage due to excessive localized stress during the formation process. Then, impurities and oil stains are cleaned from the overlap surface to ensure full contact between the metal surfaces of the two rolls of formed foil, avoiding impurities that could affect the connection. The overlap surface is then dried to prevent moisture from affecting the bonding strength between the metals during the overlap process and ensure the stability of the connection. Next, the roll head (100) is overlapped above the roll tail (200), with the overlapping area forming the overlap region (300). The overlap region (300) is then pressed and smoothed to ensure a smooth surface. Finally, use a plum blossom hammer to strike the overlap area 300 times to form multiple rows of hammer marks. The specific operation is as follows: A first number (for example, 15) of hammer marks are struck on the arc-shaped edge of the roll head 100 to form a first row of hammer marks 310 that is consistent with the arc of the front end of the roll head 100. This is mainly to provide a starting basis for the subsequent connection of multiple rows of hammer marks, and at the same time preliminarily fix the relative positions of the roll head 100 and the roll tail 200. The distribution of hammer marks along the arc-shaped edge can adapt to the shape of the roll head 100, so that the stress begins to disperse in the arc area; below the first row of hammer marks 310, a second row of hammer marks 320 with a smaller number (for example, 14) and a smaller arc is struck offset from the first row of hammer marks 310. Since the arc of the second row of hammer marks 320 is smaller than that of the first row of hammer marks 310, the stress distribution of the roll head 100 in the longitudinal direction is more reasonable, forming a gradual stress dispersion pattern; below the second row of hammer marks 320, a second number (for example, 14) and a smaller arc is struck offset from the second row of hammer marks 320 The third row of hammer marks 330 further increases the connection points and connection area, improves the ability of the roll head 100 to resist external forces, reduces the possibility of loosening or separation due to external forces, and further refines the stress transfer path through a smaller arc and staggered arrangement, so that the stress can be more evenly distributed in various parts of the roll head 100; below the third row of hammer marks 330, a third number (for example: 12) of fourth row of hammer marks 340 are staggered with the third row of hammer marks 330 to strike, and the fourth row of hammer marks 340 are arranged in a straight line, which can adjust the local stress in the area close to the right-angled side of the roll tail 200, and can be combined with the rows of arc hammer marks above to form a three-dimensional stress dispersion network. When the roll head 100 is subjected to external force, the stress can be transmitted and dispersed in the entire roll head 100 through the network composed of the arc hammer marks and the straight hammer marks, thereby effectively reducing the possibility of stress concentration and deformation.
[0024] In the above-mentioned method of joining formed foils, since the curvature of the first row of hammer marks 310 is consistent with the curvature of the curved edge, when subjected to external force, the stress can be evenly transmitted along the arc, avoiding the stress concentration at the curved edge; the smaller curvature and fewer connection points of the second row of hammer marks 320 enable the stress to be more evenly distributed during the expansion and contraction process, reducing the possibility of local stress concentration leading to fracture; the curvature of the third row of hammer marks 330 is further reduced, which can further refine the stress transfer path, so that the stress can be more evenly distributed in various parts of the roll head 100; the fourth row of hammer marks 340 is arranged in a straight line, which can adjust the local stress in the area of the right-angled edge near the roll tail 200, so that the stress distribution of the entire overlapping area 300 is more balanced. After a series of operations such as trimming, cleaning, drying and hammering with plum blossom hammers, the method provided by this application achieves a tight and firm connection between the two rolls of formed foil in the overlapping area 300. The design of multiple rows of hammer marks with different numbers and curvatures makes the overlapping area 300 have good elasticity. When the formed foil passes through the forming equipment, it can better adapt to the operation and deformation of the equipment and will not cause the overlapping area 300 to break due to expansion and contraction, thereby ensuring the continuity and stability of production and improving the efficiency of the entire formed foil production process.
[0025] In a preferred embodiment, when “cleaning and drying the overlapping surface of the roll head 100 and the roll tail 200 ”, the humidity is ensured to be less than 10%.
[0026] In another preferred embodiment, the overlapping region 300 is 80-100 mm long, which is neither too short to make connection difficult nor too long to increase operational difficulty and time costs. This allows workers to more conveniently perform steps such as trimming, cleaning, overlapping, and hammering during foil splicing, thereby improving efficiency and accuracy.
[0027] Furthermore, the first row of hammer marks 310 is positioned 4-5 mm from the arc edge, which allows for a reasonable distribution of the stress generated by hammering within the overlap region 300. If the distance is too close, hammering may cause excessive deformation of the metal at the arc edge, reducing the strength at the edge and making the arc edge susceptible to cracking during subsequent passage through the forming equipment. If the distance is too far, the stress-dispersing effect of the arc front end cannot be fully utilized, potentially concentrating stress elsewhere in the overlap region 300 and reducing connection reliability.
[0028] Furthermore, the "striking a first number of hammer marks on the arc-shaped edge of the roll head 100" includes: striking a first number of hammer marks in sequence from the middle of the arc-shaped edge of the roll head 100 to both sides. The formed foil will undergo expansion and contraction deformation when passing through the forming equipment. In this embodiment, striking the hammer marks from the middle to both sides can make the overlapping area 300 more coordinated during the expansion and contraction process. The middle is first hammered to form a connection point, and then expands to both sides, so that the expansion and contraction deformation at the foil joint can be more naturally transmitted from the middle to both sides, avoiding the stress concentration phenomenon caused by the expansion and contraction disharmony, thereby improving the expansion and contraction performance of the foil joint and reducing the possibility of the foil joint breaking during the expansion and contraction process.
[0029] Furthermore, a second number of hammer marks are struck from left to right, offset from the first row of hammer marks 310 and below the first row of hammer marks 310. In this embodiment, the staggered arrangement of the first row of hammer marks 310 and the second row of hammer marks 320 forms a synergistic structure. During expansion and contraction, this structure enables the overlap region 300 to better coordinate deformation in different directions. The order of strikes from left to right ensures the orderly nature of this coordinated deformation, allowing the foil joint to better adapt to changes in external force, thereby improving expansion and contraction performance and overall performance.
[0030] Furthermore, the second number of hammer marks 320 are struck from right to left below the second row of hammer marks 320 and offset from the second row of hammer marks 320. In this embodiment, the order of striking in different directions (the second row can be from left to right, and the third row from right to left) allows the overlapping area 300 to have better flexibility and coordination during expansion and contraction. When the formed foil expands and contracts through the forming equipment, this staggered hammer mark structure can disperse and buffer the expansion and contraction deformation in different directions and levels, avoiding stress concentration at a certain point or in a certain area. This allows the foil joint to adapt to expansion and contraction changes more naturally, greatly improving the expansion and contraction performance and reducing the risk of damage to the foil joint due to expansion and contraction. Since the reverse side, that is, the end of the coil tail 200 of the previous coiled foil, is not trimmed into an arc, but a right angle, in order to ensure the connection strength and expansion performance of the foil joint, it is still necessary to perform a reasonable foil joint operation on the right-angle end. Further, below the third row of hammer marks 330 and offset from the third row of hammer marks 330, a third number of hammer marks are struck in sequence from the middle to both sides. For the right-angle end, the stress distribution during expansion and contraction is different from that of the arc end. The method of striking the hammer marks in sequence from the middle to both sides can guide the expansion and contraction deformation to expand in an orderly manner from the middle to both sides, avoid stress concentration at the edge of the right angle, improve the coordination and stability of expansion and contraction, and reduce the damage to the foil joint caused by expansion and contraction.
[0031] In a preferred embodiment, the step S40 includes: S41. The curved edge of the volume head 100 is sequentially struck from the middle to both sides by a first number of hammer marks to form a first row of hammer marks 310; S42 below the first row of hammer marks 310 and the first row of hammer marks 310 staggered from left to right strike the second number of hammer marks to form a second row of hammer marks 320; S43 below the second row of hammer marks 320 and the second row of hammer marks 320 staggered from right to left strike the second number of hammer marks to form a third row of hammer marks 330; S44. Below the third row of hammer marks 330 and offset from the third row of hammer marks 330 , a third number of hammer marks are struck sequentially from the center to both sides to form a fourth row of hammer marks 340 .
[0032] The hammering sequence, from the center outwards and alternating left and right, ensures more uniform and coordinated expansion and contraction deformation at the foil joint. When the formed foil expands and contracts during production, stress is distributed and distributed in an orderly manner along the distribution of hammer marks. For example, hammering from the center allows the expansion and contraction to spread from the center outwards, avoiding stress concentration at one end or in a localized area. Alternating left and right hammering further enhances this coordination. This allows the foil joint to better adapt to expansion and contraction changes, reducing stress concentration and fracture caused by uncoordinated expansion and contraction, and further improving expansion and contraction performance.
[0033] The following is a detailed description of the technical solutions and effects of the present invention. It should be noted that the following examples are only intended to further explain the present invention and do not limit the technical solutions of the present invention. Example 1
[0034] On the foil splicing platform, first trim the front end of the roll head 100 of the next roll of formed foil into an arc shape, and ensure that it is smooth and free of burrs. Clean and dry the overlapping surface of the roll head 100 of the next roll of formed foil and the roll tail 200 of the previous roll of formed foil, with the humidity less than 10%. Then overlap the roll head 100 on top of the roll tail 200, and the overlapping area is the overlapping area 300. The length of the overlapping area 300 is 100 mm. Press and smooth the overlapping area 300. Use a plum blossom hammer to knock 15 hammer marks on the curved edge of the roll head 100 (at a distance of 5 mm) to form a first row of hammer marks 310. The curvature of the first row of hammer marks 310 is kept consistent with the curvature of the curved front end of the roll head 100. 14 hammer marks are struck below the first row of hammer marks 310 and offset with the first row of hammer marks 310 to form a second row of hammer marks 320, and the curvature of the second row of hammer marks 320 is smaller than that of the first row of hammer marks 310; 14 hammer marks are struck below the second row of hammer marks 320 and offset with the second row of hammer marks 320 to form a third row of hammer marks 330, and the curvature of the third row of hammer marks 330 is smaller than that of the second row of hammer marks 320; 12 hammer marks are struck below the third row of hammer marks 330 and offset with the third row of hammer marks 330 to form a fourth row of hammer marks 340, and the fourth row of hammer marks 340 is distributed in a straight line; after the foil is joined, the tensile test is used to test its fracture resistance, and the specific results are shown in Table 1; Comparative Example 1 Comparative Example 1 differs from Example 1 in that the four rows of hammer marks have the same number of hammer marks, i.e., each row has 11 hammer marks, and the arc of each row of hammer marks is also consistent. The other methods and steps are the same as those in Example 1. After the foils were joined, a tensile test was performed to test their fracture resistance. The specific results are shown in Table 1. Example 2
[0035] The difference between Example 2 and Example 1 is that the first row of hammer marks 310 is struck sequentially from the center to the sides, the second row of hammer marks 320 is struck from left to right, the third row of hammer marks 330 is struck from right to left, and the fourth row of hammer marks 340 is struck sequentially from the center to the sides. The remaining methods and steps are the same as those in Example 1. After the foils were joined, a tensile test was performed to test their fracture resistance. The specific results are shown in Table 1. Table 1 Comparison of fracture resistance of overlapped areas
[0036] The data in Table 1 above show that, using the method provided in the present application, i.e., Example 1, after a series of operations such as pruning, cleaning, drying, and hammering with a plum blossom hammer, the design of multiple rows of hammer marks with different numbers and curvatures makes the overlapping area 300 have good elasticity, thereby enhancing its fracture resistance and reducing the fracture rate; the method provided in Example 2 can further reduce the fracture rate to 9%.
[0037] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should all be included in the scope of protection of the present invention.
Claims
1. A method for joining formed foils, characterized in that: The following steps are involved: S10. The front end of the head of the rear roll of foil is trimmed into a curved edge, and the front end of the tail of the front roll of foil is trimmed into a right angle edge, and ensure smooth and burr-free edges; S20 clean and dry the roll head and the roll tail portion of the overlapping surface; S30. The roll head is overlapped above the roll tail, the overlapping area is the overlapping area, and press to smooth the overlapping area; S40. Using a plum hammer to strike the overlap area to complete the front and rear rolled foil joining operation: striking a first number of hammer marks on the curved edge of the roll head to form a first row of hammer marks, wherein the curvature of the first row of hammer marks is consistent with the curvature of the curved front end of the roll head; A second row of hammer marks is struck below the first row of hammer marks, offset from the first row of hammer marks, to form a second row of hammer marks, wherein the second number is smaller than the first number, and the arc of the second row of hammer marks is smaller than that of the first row of hammer marks; The second number of hammer marks are struck below the second row of hammer marks, offset from the second row of hammer marks, to form a third row of hammer marks, wherein the arc of the third row of hammer marks is smaller than that of the second row of hammer marks; A third number of hammer marks are struck below the third row of hammer marks, offset from the third row of hammer marks, to form a fourth row of hammer marks, which are arranged in a straight line.
2. The method for joining chemically formed foils according to claim 1, characterized in that: When "cleaning and drying the overlapping surface of the roll head and the roll tail", the humidity is ensured to be less than 10%.
3. The method for joining chemically formed foils according to claim 1, characterized in that: The length of the overlapping area is 80-100 mm.
4. The method for joining chemically formed foils according to claim 1, characterized in that: The first row of hammer marks is 4-5 mm away from the arc edge.
5. The method for joining chemically formed foils according to claim 1, characterized in that: The “striking a first number of hammer marks on the arc-shaped edge of the roll head” includes: sequentially striking a first number of hammer marks from the middle of the arc-shaped edge of the roll head toward both sides.
6. The method for joining chemically formed foils according to claim 1, characterized in that: Below the first row of hammer marks, strike the second number of hammer marks from left to right, offset from the first row of hammer marks.
7. The method for joining chemically formed foils according to claim 1, characterized in that: The second number of hammer marks are struck from right to left below the second row of hammer marks, offset from the second row of hammer marks.
8. The method for joining chemically formed foils according to claim 1, characterized in that: Below the third row of hammer marks, the third number of hammer marks are struck in sequence from the middle to both sides, offset from the third row of hammer marks.
9. The method for joining chemically formed foils according to claim 1, characterized in that: The S40 includes: S41. A first number of hammer marks are struck on the curved edge of the volume head from the middle to the sides to form the first row of hammer marks. S42. Strike a second number of hammer marks below the first row of hammer marks, offset from left to right, to form a second row of hammer marks. S43. Striking the second number of hammer marks below the second row of hammer marks from right to left, offset from the second row of hammer marks, to form a third row of hammer marks; S44. Below the third row of hammer marks, strike a third number of hammer marks from the center outward, offset from the third row of hammer marks, to form a fourth row of hammer marks.