JP4505569B2 - Drawing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a drawing method, and more particularly to a drawing method of a clad material such as an aluminum clad material in which aluminum and a steel plate are laminated, which is used for a case of a coin-type battery.
[0002]
[Prior art]
Since the coin-type battery is small and thin, it is widely used when it is required to reduce the size of a wristwatch or a hearing aid, or when it is required to be thin such as an IC card. Recently, there has been developed a coil-type battery case in which a group of electrode plates having a winding structure is accommodated so as to obtain high load discharge characteristics.
[0003]
The structure of the coin-type battery in which the electrode group having the winding structure is housed in the coin-type battery case will be described with reference to FIG. As shown in a sectional view in FIG. 8, a gasket 33 is mounted between a battery case 31 formed in a circular half-shell and a sealing plate 32, and the battery case 31 is caulked and sealed in a winding structure. The electrode plate group 34 is accommodated.
The electrode plate group 34 is formed by winding a positive electrode plate and a negative electrode plate with a separator interposed therebetween, and space efficiency is ensured so that a useless space is not formed in a circular space formed by the sealing plate 32. Therefore, it is possible to construct a battery with a high volume efficiency and a large battery capacity per volume of the battery in combination with the winding structure.
[0004]
When manufacturing this coin-type battery, the negative electrode lead of the electrode plate group 34 is resistance-welded to the sealing plate 32, the positive electrode lead is ultrasonically welded to the inner surface of the battery case 31, and then the gasket is formed on the outer peripheral surface of the sealing plate 32. 33, the battery case 31 is put on the sealing plate 32, and the opening end side of the side peripheral surface of the battery case 31 is bent inward, so that the battery case 31 and the sealing plate 32 are connected as shown in FIG. It is possible to obtain a coin-type battery in which the electrode plate group 34 having a wound structure is accommodated while the space is sealed (see, for example, Patent Document 1).
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 2002-117900
[Problems to be solved by the invention]
Conventionally, SUS (stainless steel) has been used as the material for the battery case and sealing plate of the coin-type battery having the above-described structure, but SUS is excellent in corrosion resistance but has a high contact resistance. In recent years, the use of a clad material in which a soft metal such as aluminum or an aluminum alloy and a steel plate such as SUS are laminated has been studied in consideration of mechanical strength, drawability, corrosion resistance, and low contact resistance. ing.
[0007]
On the other hand, when manufacturing the battery case of the coin type battery as described above, after punching the material into a disk shape, the battery case is manufactured by drawing the punched material, but aluminum and SUS are used as the material. When the laminated aluminum clad material is used, there is a problem that burrs (small protrusions) are generated on the aluminum side at the time of drawing because the elongation amounts of SUS and aluminum are different.
In the coin-type battery as described above, when a burr occurs in the battery case, the battery easily causes an internal short circuit. When such an internal short circuit occurs, the battery function is lost, so that the above burr does not occur. It is necessary to. Therefore, conventionally, has been to eliminate the burr at the mold of the narrowing device, had been to eliminate the burr by adjusting the punch and die centering accuracy, prevents this adjustment alone is burrs I couldn't.
[0008]
Further, as shown in FIG. 8, it is necessary to form a shoulder R on the sealing plate of the coin-type battery, and when an aluminum clad material is used as the sealing plate material, an end face is formed to form the shoulder R on the sealing plate. When aluminum is struck up, the thickness of the aluminum is so thick that the surplus aluminum is on the end surface and the SUS end surface is covered with aluminum. If such aluminum protrusion does not occur, the shoulder R of the sealing plate cannot be reduced, and the shoulder R of the sealing plate becomes large.
[0009]
The present invention has been made in view of the above-described problems, and hardly generates burrs of soft metal such as aluminum during drawing, and can be made minute even if burrs are generated. It is an object of the present invention to provide a drawing method for a clad material in which the end face of a steel plate is not covered with a soft metal.
[0010]
[Means for Solving the Problems]
The invention according to claim 1 is a drawing method of a clad material in which a soft metal and a steel plate are laminated, and a blanking step of punching the clad material into a disc shape, and a cylindrical body shape having a flange portion of the punched disc-like clad material A first drawing step of drawing into a flange, a flange crushing step of crushing a portion of the soft metal of the flange portion, a trimming step of cutting out a portion of the flange portion at a position where the soft metal is crushed, and the flange portion And a second drawing step to be started.
The invention according to claim 2 is characterized in that, in the method of drawing a clad material according to claim 1, the soft metal is aluminum or an aluminum alloy, and the steel plate is SUS.
[0011]
According to the first or second aspect of the invention, since the thickness of the soft metal such as aluminum around the flange portion of the clad material is reduced by the flange crushing step, the flange portion is reduced in the second drawing step. , The soft metal burrs hardly occur, and even if burrs are generated, they can be made minute.
[0012]
According to a third aspect of the present invention, in the drawing method of the clad material in which the soft metal and the steel plate are laminated, the blanking step of punching the clad material into a disc shape, and the punched disc-like clad material has a flange portion and an inclined portion. Drawing the head into a shape and crushing a part of the soft metal in the flange part, crushing the head part and crushing the flange, trimming the part of the flange part at the position where the soft metal is crushed, and the flange part It consists of a second drawing step to be launched, a first forming step in which the soft metal protruding from the upper end by the second drawing step is hit, and a second forming step in which only the end surfaces of the steel plates are hit and the end surfaces are aligned. It is characterized by.
According to a fourth aspect of the present invention, in the method for drawing a clad material according to the third aspect, the soft metal is aluminum or an aluminum alloy, and the steel plate is SUS.
[0013]
According to the invention according to claim 3 or claim 4, since the thickness of the soft metal such as aluminum around the flange portion of the clad material is reduced by the flange crushing step, the flange is formed in the second drawing step. When the part is started up, there is less soft metal protruding, and there is a process of hitting the protruding soft metal, so that the shoulder metal is not exposed to the end surface of the soft metal in the process of forming the shoulder R. It is possible to prevent the situation where the soft metal is covered, and even if the shoulder R is reduced, the soft metal does not protrude.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment in which the method for drawing a clad material of the present invention is applied to the manufacture of a battery case of a coin-type battery using an aluminum clad material will be described with reference to FIGS.
FIG. 1 shows each step of finishing an aluminum clad material into a battery case, a blanking step (a) in which the aluminum clad material is punched into a disc shape, and the punched disc-shaped aluminum clad material 1 into a cylindrical shape having a flange portion 2. A first drawing step (b) for drawing, a flange crushing step (c) for crushing a portion of the aluminum of the flange portion 2, a trimming step (d) for cutting off a portion of the flange portion 2 at a location where the aluminum is crushed, It comprises a second drawing step (e) for raising the flange portion 2 and a molding step (f) for adjusting the shape of the battery case.
[0015]
For aluminum clad material, SUS with nickel plating on the surface and aluminum or aluminum alloy are superposed and cold rolled and joined, followed by diffusion annealing, and then cold finish rolling or cold finish rolling and final annealing. It is obtained by applying. In the blanking step (a), this aluminum clad material is punched into a disk shape by a punching die and a punching punch corresponding thereto. In the first drawing step (b), the punched disc-shaped aluminum clad material 1 is drawn into a cylindrical shape having a flange portion 2 by a die and a drawing punch for drawing the outer contour. Is done.
[0016]
Then, in the next flange crushing step (c), as shown in detail in FIG. 2, a part of the aluminum 4 of the flange portion 2 is crushed by the flange crushing punch 5, knockout 6, and die 7 to thin the aluminum. . In FIG. 2, an opening is formed in the center of the die 7, and a knockout 6 connected to a base via a spring (not shown) is disposed in the opening of the die 7. A flange crushing punch 5 is arranged so as to face the knockout 6. When the flange crushing punch 5 is lowered with the aluminum clad material 1 in which the SUS 3 and the aluminum 4 are laminated and the flange portion 2 is formed on the knockout 6 and the die 7, the knockout 6 is spring-loaded. It moves downward against the elastic force, and a part of the aluminum 4 of the flange portion 2 is crushed.
[0017]
Next, as shown in detail in FIG. 3 in the trimming step (d), the aluminum clad material 1 in which a part of the aluminum 4 of the flange portion 2 is crushed is trimmed punch 8, knockout 9, trimming die 10, product guide. 11, a part of the flange portion 2 is cut off at a position where the aluminum 4 is crushed. As in FIG. 2, the trimming die 9 has an opening at the center, and the knockout 9 is disposed in the opening of the trimming die 10. When the trimming punch 8 is lowered in a state where the flange portion 2 of the aluminum clad material 1 on which the product guide 11 is placed in the cylindrical body is placed on the upper surface of the trimming die 10, the trimming punch 8 opens the opening of the trimming die 10. The knockout 9 moves downward against the elastic force of the spring, and a part of the flange portion 2 is cut off at the position where the aluminum 4 is crushed.
[0018]
As shown in detail in FIG. 4 in the second drawing step (e), the aluminum clad material 1 from which a part of the flange portion 2 has been cut is then formed into the flange portion 2 by the punch 12, the knockout 13 and the die 14. You can stand up. That is, when the punch 12 is lowered while the flange portion 2 of the aluminum clad material 1 is placed on the die 14, the punch 12 enters the opening of the die 14, and the knockout 13 is the spring Since it moves downward against the elastic force, the flange portion 2 enters the gap between the die 14 and the punch 12, and the flange portion rises.
[0019]
The battery case is completed by further forming the cylindrical workpiece with the flange portion 2 raised in the next forming step (f). In the second drawing step and the forming step, the flange portion of the aluminum clad material 1 is formed. Since the thickness of the aluminum at the end portion 2 is thin as shown in FIG. 4, almost no burrs of aluminum are generated, and even if burrs are generated, it can be made minute.
[0020]
Next, an embodiment in which the method for drawing a clad material according to the present invention is applied to the manufacture of a sealing plate for a coin-type battery using an aluminum clad material will be described with reference to FIGS.
FIG. 5 shows a partial enlarged view of each process of finishing the aluminum clad material into a sealing plate, a blanking process (a) in which the aluminum clad material is punched into a disk shape, and the punched disk-shaped aluminum clad material 1 is inclined with respect to the flange portion 2. The head is squeezed into a shape having a part, and part of the aluminum of the flange part 2 is crushed. c), a second drawing step (d) for raising the flange portion 2; a first forming step (e) for striking the aluminum protruding from the upper end in the second drawing step; and hitting only the end surface of the SUS. And a second molding step (f).
[0021]
As in the case of the battery case, the aluminum clad material is punched into a disk shape by a punching die and a punching punch corresponding thereto in the blanking step (a). The punched disk-shaped aluminum clad material 1 is then subjected to a disk-shaped aluminum clad by punch 15, knockout 16 and die 17 as shown in detail in FIG. 6 in the head drawing and flange crushing step (b). While the head of the material 1 is squeezed, the flange portion 2 is formed. At the same time, a part of the aluminum 4 of the flange portion 2 is crushed. That is, when the punch 15 is lowered while the disc-shaped aluminum clad material 1 is placed on the knockout 16 and the die 17, the punch 15 enters the opening of the die 17, and the knockout 16 is elastic of the spring. It moves downward against the force, the head is squeezed, and the flange portion 2 is formed. At the same time, a part of the aluminum 4 of the flange portion 2 is crushed by the step portion on the periphery of the punch 15.
[0022]
Next, in the trimming step (c), the aluminum clad material 1 in which a part of the aluminum 4 of the flange part 2 is crushed is cut out at a position where the aluminum 4 is crushed in the same manner as in FIG. After that, the flange portion 2 is raised in the second drawing step (d) as in FIG.
The workpiece from which the flange portion 2 has risen is the next first forming step (e). As shown in detail in FIG. 7, the punch 18, the knockout 19, the die 20, and the simple 21, only the bare aluminum 4 is used. Is crushed. That is, when the punch 18 is lowered along the simple 21 in a state where the workpiece having the flange portion raised is placed on the knockout 19 and the die 20, the knockout 19 is moved downward against the elastic force of the spring. It moves, only the aluminum 4 is beaten by the step 23 on the peripheral edge of the punch 18, and the protruding aluminum is crushed. At this time, since the protrusion 22 is formed at the end of the die 20, a slight shoulder R is formed on the lower surface of the workpiece. Next, in the second forming step (f), only the end face of SUS3 is hit by this work, and the upper end face is aligned and a shoulder R is formed at the lower part of the work. The punch, die, etc. in this case have the same configuration as in FIG. 7, and by using a device in which the stepped portion of the peripheral edge of the punch 18 is formed up to the end of SUS3, the SUS3 is hit and the shoulder is placed on the lower part of the workpiece. R can be formed.
[0023]
As described above, a coin-type battery sealing plate can be manufactured. However, since the thickness of the aluminum in the flange portion at the end of the aluminum clad material is reduced by the flange crushing step, the second diaphragm When the flange part is raised in the process, the amount of protruding aluminum is reduced, and after the process of crushing the protruding aluminum, the shoulder R is formed by hitting only SUS. Therefore, the surplus aluminum in the process of forming the shoulder R Does not protrude from the end face, and even if the shoulder R is reduced, the aluminum meat can be prevented from protruding.
[0024]
In the above embodiment, the example in which the drawing method of the present invention is applied to a battery case or a sealing plate of a coin type battery has been described. However, the drawing method of the present invention is applicable to a case of a coin type electronic component or the like. It can also be applied to the molding of other workpieces, and is also applicable to the battery case and sealing plate of coin-type batteries using a normal flat plate group, not a wound plate group. be able to.
Furthermore, in the above-described embodiment, the aluminum clad material in which the SUS and the aluminum plate on which the surface is plated with nickel is overlapped and cold-rolled and joined as a clad material has been described as an example. Can also be applied to clad materials using soft metals such as lead other than aluminum and clad materials using steel plates other than SUS.
[0025]
【The invention's effect】
As described above in detail, according to the drawing method of the invention according to claim 1 or 2, the thickness of the soft metal such as aluminum around the flange portion of the clad material is reduced by the flange crushing step. In addition, since only the flange portion is raised in the second drawing step, soft metal burrs hardly occur in the second drawing step, and even if burrs are generated, it can be made minute .
[0026]
Further, according to the drawing method according to claim 3 or claim 4, since the thickness of the soft metal such as aluminum around the flange portion of the clad material is reduced by the flange crushing step, the second drawing When the flange part is raised in the process, the amount of protruding soft metal is reduced, and the process of hitting the protruding soft metal is provided, so that the excess metal of the soft metal does not appear on the end face in the process of forming the shoulder R. Even if the shoulder R is made small, it is possible to prevent the situation that the end surface of the steel plate is covered with a soft metal.
[Brief description of the drawings]
FIG. 1 is a diagram showing each step of an embodiment in which a drawing method of a clad material of the present invention is applied to manufacture of a battery case.
FIG. 2 is a diagram showing details of a flange crushing process.
FIG. 3 is a diagram showing details of a trimming process.
FIG. 4 is a diagram showing details of a second drawing process.
FIG. 5 is a diagram showing each step of an embodiment in which the method for drawing a clad material of the present invention is applied to manufacture of a sealing plate for a coin-type battery.
FIG. 6 is a diagram showing details of a head drawing and flange crushing process.
FIG. 7 is a diagram showing details of a first molding step.
FIG. 8 is a diagram showing a structure of a coin-type battery in which a wound electrode group is housed in a case.
[Explanation of symbols]
1 Aluminum clad material 2 Flange part 3 SUS
4 Aluminum 5 Flange crushing punch 6, 9, 13, 16, 19 Knockout 7, 14, 17, 20 Die 8 Trimming punch 10 Trimming die 11 Product guide 12, 15, 18 Punch 21 Simple 22 Protruding part 23 Step part

Claims (4)

In a drawing method of a clad material in which a soft metal and a steel plate are laminated, a blanking process in which the clad material is punched into a disc shape, and a first draw in which the punched disc-like clad material is drawn into a cylindrical shape having a flange portion. A flange crushing step of crushing a part of the soft metal of the flange portion, a trimming step of cutting off a part of the flange portion at a position where the soft metal is crushed, and a second drawing step of raising the flange portion A method for drawing a clad material, comprising: The method for drawing a clad material according to claim 1, wherein the soft metal is aluminum or an aluminum alloy, and the steel plate is SUS. In a drawing method of a clad material in which a soft metal and a steel plate are laminated, a blanking process in which the clad material is punched into a disc shape, a punched disc-like clad material is drawn into a shape having a flange portion and an inclined portion, and a flange is formed. A head squeezing and flange squeezing step for smashing a part of the soft metal; a trimming step for cutting off a part of the flange portion at the position where the soft metal is smashed; and a second squeezing step for raising the flange portion; A clad material comprising: a first forming step of hitting a soft metal protruding from an upper end by a second drawing step; and a second forming step of hitting only an end face of a steel plate to align the end faces. Drawing process. The method for drawing a clad material according to claim 3, wherein the soft metal is aluminum or an aluminum alloy, and the steel plate is SUS.

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