JPH0222981B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for manufacturing an anode can for a button-type battery. [Prior art] The conventional method for producing anode cans for button-type batteries is to draw a flat steel plate into the shape of an anode can, and then cut it using a mold with a diameter approximately equal to the external dimensions of the opening. As a result, the inner surface of the opening of the manufactured anode can had a rounded shape as shown in FIG. Conventionally, such anode cans were used to manufacture button-type batteries as shown in Figure 2, but the local digging force of the packing at the anode can opening was not sufficient, and sufficient leakage resistance was still required. is not obtained. In order to solve these problems, Figures 6 and 7
A method of manufacturing an anode can as shown in the figure has been proposed. In other words, the method for manufacturing the anode can shown in FIGS. 6 and 7 is to cut the vertical surface of the recess formed by drawing from the inner or outer surface. teeth,
When cutting from the inner surface, burrs as shown in FIG.
When cutting from the outside surface, burrs will be formed along the cutting direction as shown in Figure 7 (arrows indicate the cutting direction), and it cannot be used as an anode can for button-type batteries. I learned that there isn't. [Problems to be Solved by the Invention] As a result of examining the relationship between the anode can, the cathode can, and the packing, the present inventors found that the penetration of the inner surface of the anode can opening into the packing has a large influence on leakage resistance. They discovered that if an edge is formed on the inner surface of the anode can opening, excellent clamping force can be obtained. From this point of view, according to the conventional examples shown in FIG. 2, the inner surface of the opening of the anode can is rounded, while in the ones shown in FIGS. 6 and 7, a burr is provided. There is a problem in that these are formed during the manufacturing process, and an improvement is desired. [Means for solving the problem] A circular plate connected to the peripheral edge of the steel plate by a connecting piece is punched out from a flat steel plate, and this circular plate is drawn to form a circular concave portion with a warm surface shape. At the same time, a flat plate part is formed on the peripheral edge of the circular recess to form a dish-shaped part, and the flat plate part of the dish-shaped part is held on the peripheral part of the mold, and then a punch having an inner diameter equal to the inner diameter of the circular recess is formed. By pressing the circular recess, the flat plate portion is raised vertically between the peripheral edge of the mold and the punch to form an anode can, thereby causing burrs at the opening of the anode can and deformation of the anode can. This makes it possible to manufacture anode cans in an extremely short process without any problems. [Example] Hereinafter, an example of the present invention will be described in detail based on FIG. 4. A flat steel plate 1 made of a cold-rolled steel plate formed into a band with a width of 20 mm and a thickness of 0.25 mm is pulled out from the hoop 2 by the conveying roller 3 in the required amount, and a punch 4 is used to punch out the flat steel plate 1. A disk 6 is punched out and connected to the peripheral edge by connecting pieces 5, 5'. The disk 6 is drawn to a depth of 2 mm by a drawing die 7,
A circular recess 8 having a cross-sectional shape is formed, and a portion larger than the size of the circular recess is punched concentrically using a punching die 9, and a flat plate portion 10 is formed at the peripheral edge.
A dish-shaped part 11 having a thickness of 1.5 mm and a depth of 2 mm is formed. After that, the flat plate part 10 of the dish-shaped part 11 is molded into the mold 1.
2, and press the portion excluding the flat plate portion 10 with a punch 13 having an inner diameter equal to the inner diameter of the dish-shaped component 11. At this time, a space 18 equal to the length of the flat plate part 10 is provided below the plate-shaped part 11 held by the mold 12, and when the punch 13 is moved by this spatial distance, the flat plate part 10 is gradually raised between the punch 13 and the inner wall of the mold 12, and after the punch 13 has finished lowering, the anode can 14 with the flat plate portion 10 vertical is manufactured.
An edge 15 is formed on the inner surface of this anode can 14 . In addition, 19 in FIG. 3 is the bottom part 19 of the dish-shaped part 11 in FIG. 4, and 10 in FIG. 3 is the flat plate part 10 formed at the peripheral part of the dish-shaped part 11 in FIG. Corresponds to each. When a battery is assembled using the anode can 14 manufactured in this way, as shown in FIG. Since the rising edges 16 face each other and pinch the packing 17, it is possible to obtain a battery with extremely excellent leakage resistance. The following table shows how 100 LR1130 type alkaline batteries were made using the anode can manufactured by the present invention and the conventional anode can shown in Figure 1 at 60℃ and relative humidity.
The table shows the results of investigating the number of leaks when stored at 90%, 20 days, and 40 days.

〔Effect of the invention〕

As is clear from the table, batteries manufactured using the anode can of the present invention have a small number of leaks and are excellent in leakage resistance, but batteries manufactured using the conventional anode can shown in FIG. It is thought that the battery leaked because the inner surface of the opening of the anode can was rounded, and strong clamping by the edges could not be achieved as in the present invention. Further, the manufacturing method of the present invention does not produce burrs even after cutting, and the anode can can be manufactured in an extremely short process.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an anode can manufactured by a conventional manufacturing method, and FIG. 2 is a partial sectional view of a button-type alkaline battery sealed using the anode can of FIG. 3 and 4 are diagrams showing the manufacturing process of the anode can of the present invention. The steel plate shown in FIG. 4 is a cross-sectional view taken along the line A-A in FIG. A partial cross-sectional view of a button-type alkaline battery showing a sealed state using a can, and FIGS. 6 and 7 are cross-sectional views showing anode cans manufactured by other conventional methods. 1... Flat steel plate, 5, 5'... Connection piece, 6
... Disk, 8 ... Circular recess with cross-sectional shape, 10
... Flat plate part, 11 ... Dish-shaped part, 12 ... Mold, 13 ... Punch, 14 ... Anode can, 15 ...
Etsuji.

Claims (1)

[Claims] 1 A circular plate is punched out from a flat steel plate to be connected to the peripheral edge of the steel plate by a connecting piece, and this circular plate is drawn to form a circular recess with a cross-sectional shape, and a circular recess is formed on the peripheral edge of the circular recess. By forming a flat part to form a dish-shaped part, holding the flat part of the dish-shaped part on the peripheral edge of a mold, and then pressing the circular recess with a punch having an inner diameter equal to the inner diameter of the circular recess. . A method for manufacturing an anode can for a button-type battery, characterized in that the flat plate portion is raised vertically between a peripheral edge of a mold and a punch to form an anode can.