JPH0711952B2 - Battery battery case lid and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE lid and its of the present invention is a battery electric tank cans
The manufacturing method of
The shape or structure of the caulking part of the battery case
Good and improved manufacturing methods of such lids
is there.

[0002]

2. Description of the Related Art FIG. 1 is a front view in half section showing a conventional silver oxide battery for explaining an interesting prior art of the present invention. 2 to 8 are central longitudinal cross-sectional views sequentially showing the manufacturing process of the lid of FIG.

The silver oxide battery as shown here is a so-called button type battery which is widely used as a power source for electronic wrist watches, for example. To describe this structure, the anode can 1 which is the main body of the battery case is made of, for example, nickel-plated iron, inside which the anode acting substance 2, the separator 3 and the cathode acting substance 4 are arranged in layers. To be done. On the cathode active substance 4, a cathode can 5 is covered as a lid of the battery case. The cathode rod 5 is made of stainless steel, and has a copper layer formed on its inner surface and a nickel layer formed on its outer surface.

The cathode can 5 has a peripheral portion 6 having a U-shaped cross section. Substantially outside this peripheral portion 6, a packing 7
Is arranged, and when the open end edge portion of the anode can 1 is caulked inside, it engages with the peripheral edge portion 6 via the packing 7.
This realizes a sealed structure that should prevent the electrolyte leakage phenomenon.

Since the cathode can 5 as described above is provided with the peripheral portion 6 having a U-shaped cross section, the buckling force of the caulking portion is strengthened. Since the hardness greatly contributes to the prevention of electrolyte leakage, further strengthening is desired.

The insufficient hardness of the peripheral edge portion 6, which is the crimped portion of the conventional cathode can 5, is considered to be due to the manufacturing process described below. First, in a conventional manufacturing process, as shown in FIG. 2, a blank 8 cut into a desired size is prepared. Next, as shown in FIG. 3, it is pressed by an upper drawing die 9 and a lower drawing die 10,
The blank 8 undergoes the first drawing process. At this time, the outer peripheral portion of the blank 8 is strongly sandwiched, for example, in order to prevent wrinkles, and thus the wall thickness of the outer peripheral portion is reduced. Next, as shown in FIG. 4, the second drawing process is performed by the upper drawing die 11 and the lower drawing die 12. Here again, the thickness of the outer peripheral portion of the workpiece 13 is further reduced. Next, as shown in FIG. 5, the workpiece 13 is cut to have a desired outer diameter. Next, as shown in FIG. 6, the flange portion 14 on the outer periphery of the workpiece 13 is preliminarily raised. Further, as shown in FIG. 7, the flange portion 14 is completely raised. Then, finally, as shown in FIG. 8, the space between the flange portion 14 and the main body portion of the workpiece 13 is narrowed by further pressing the flange portion 14 inward. As a result, the cathode can 5 is obtained, and the flange portion 14 constitutes a part of the above-mentioned peripheral portion 6 having a U-shaped cross section.

[0007]

In such a conventional process, particularly, FIGS. 3 and 4 and FIGS. 6 to 8 are used.
It was found that the above process becomes a problem. This will be described with reference to FIG. FIG. 9 is an enlarged view of the peripheral portion of the lid.

First, the first problem is that the wall thickness of the outer peripheral portion of the blank 8 or the workpiece 13 is reduced in the steps of FIGS. 3 and 4. This outer peripheral portion is finally brought to a position on the outer peripheral side 6a of the peripheral portion 6 having a U-shaped cross section. Therefore, the thinned outer peripheral side 6a is naturally inferior in strength. The second problem is the process of FIGS.
Is folded back to form the peripheral portion 6 having a U-shaped cross section. That is, in the steps of FIGS. 6 and 7, only the naturally curved portion is formed by folding back the flange portion 14, and work hardening does not occur. In this state, the process shown in FIG. 8 is performed, and as shown in FIG.
If pressure is applied so that the distance between the outer peripheral side 6a and the inner peripheral side 6b is narrowed, the curved portion 6c is thinned and becomes weak.

Due to such a cause, the strength of the outer peripheral side 6a of the peripheral edge portion 6 which is required to sufficiently withstand the pressure generated in the caulking step is reduced.

As described above, conventionally, it is simply considered that by folding the peripheral portion into a U-shaped cross section, the strength of the lid of the cathode can, that is, the lid of the battery container is increased, and accordingly, the property of preventing leakage of the electrolyte is increased. It was being done. That is, it has been considered that the liquid leakage resistance is satisfied only by performing a simple process. However, in practice, it has become clear that there is still room for improvement in terms of both strength and leakage resistance.

[0011]

The present invention seeks to remedy these remaining problems. The present invention, in short, improves the cross-sectional shape of the battery case lid.
Techniques and methods of making good Una cell battery jar cans lid to a technique for improving the. That is, by changing the cross-sectional shape of the lid of the battery case, the lid having a constant volume can exert the maximum effect in terms of strength and leakage resistance. All the volume of the lid contributes to the improvement of strength and the resistance to liquid leakage most efficiently.

More specifically, the lid of the battery case according to the present invention is formed with a peripheral portion having a U-shaped cross section, and the peripheral portion having the U-shaped cross section is the center of the battery casing. The peripheral edge portion is curved to one side to form an inner half of the peripheral edge portion having a U-shaped cross section, and the peripheral edge portion is further curved to the outer side to form an outer half of the peripheral edge portion having a U-shaped cross section,
The peripheral portion having a U-shaped cross section has a portion corresponding to the outer half of the U-shaped section bent and bent from the blank to the other side, and the tip of the bent outer half of the blank is directed and pressed to one side. , The central portion of the main plane portion of the blank is pressed toward the other side and the central portion of the main plane portion of the blank is bulged to the other side, whereby a U-shaped section in the periphery of the central portion of the main plane portion of the blank Is formed, and a curved portion having a U-shaped cross section is press-molded to the other side in a state in which the tip end of the bent outer half of the blank is directed to one side and maintained pressed. To do.

According to the present invention, the central portion of the main plane portion of the blank is bulged to the other side while the tip end portion of the outer half bent and raised from the blank is kept pressed to one side. A U-shaped section is formed on the peripheral edge of the central portion of the plane section, and a curved section having a U-shaped section is press-molded to the other side. Provided is a battery case lid which is suppressed as compared with the conventional case. As a result, the lid of the battery case can be provided that can withstand the caulking pressure more than ever before.

According to the manufacturing method of the present invention, in the lid of the battery case described above, the portion corresponding to the outer half of the U-shaped section of the periphery of the blank is bent to the other side, and the section U of the periphery is bent. The tip of the portion corresponding to the outer half of the U-shaped cross-section of the bent portion is defined by the die, while defining the outward expansion of the outer circumference of the blank in which the portion corresponding to the outer half of the character is bent and raised. A blank having the action surface for pushing the blank on one side and a knockout having a central action portion for pushing the other side on the central portion of the main plane portion of the blank in an area smaller than the peripheral portion having a U-shaped cross section Pressing in a direction intersecting with the plane, and as a result of the mutual action of the working surface facing one side of the punch and the central working part facing the other side of the knockout, the main plane part of the blank has a U-shaped cross section. By bulging to the other side with respect to the half, the U-shaped section is formed at the peripheral edge of the central portion of the main plane portion of the blank, and the bent and raised tip of the outer half is pressed and maintained on one side. In this state, the curved portion having a U-shaped cross section is press-molded to the other side.

According to the present invention, the outer half having a U-shaped cross section is bent and bent from the blank, and the bent half of the outer half is pressed and maintained on one side so that the central portion of the main plane portion of the blank is on the other side. By bulging into a blank, a U-shaped section is formed at the peripheral edge of the central portion of the main plane portion of the blank, and a curved section having a U-shaped section is pressed and formed on the other side. It is possible to easily manufacture the lid of the battery container case in which the decrease in the thickness of the outer half due to the processing of 1 is small.

Therefore, the object of the present invention is to
It withstands pressure enough to achieve the desired sealing structure.
The lid and the lid of the battery case that has a structure that can prevent electrolyte leakage.
Is to provide a method for manufacturing the same.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of a battery case according to an embodiment of the present invention will be clarified by explaining the manufacturing method thereof with reference to the drawings.

10 to 12 are central longitudinal sectional views sequentially showing steps included in the method for obtaining the lid of the battery case according to the embodiment of the present invention. 13 is shown in FIG.
It is an enlarged view of the process of.

Referring to FIG. 10, a blank 21 is prepared which is cut in accordance with the size of the cathode can as the lid of the battery case to be obtained. As for the size of the blank 21, a bending margin of bending processing described later is considered.

Referring to FIG. 11, blank 21 is bent and raised at its outer peripheral portion by punch 22 and die 23. At this time, since the bent and raised portion 24 of the blank 21 existing between the punch 22 and the die 23 has a sufficient clearance, the thickness of the blank 21 is not thinned unlike drawing. . This bend
Raised part 24 is a U-shaped cross section of the lid of the battery case.
The outer diameter of the part is the outer half of the
The inner diameter of the die 23 is selected so as to be equal to the outer diameter of the cathode rod to be obtained.

With reference to FIGS. 12 and 13, the blank 21 as the workpiece obtained in the step of FIG. 11 has a die 26 which defines the outward expansion of its outer periphery.
That is, while being confined by the die 26, it is pressed between the punch 27 and the knockout 28, and is forcibly formed into a desired shape. More specifically, the punch 27 is formed with an action portion 29 that presses the tip of the bent and bent portion 24. The acting portion 29 forms a horizontal acting surface 29a facing downward. Knockout 28 is provided with a central working portion 31 facing and upwardly for pressing the central portion of the main plane of the blank 21, the outer peripheral surface of the central working portion 31, good
Preferably, the inclined working surface 32 that faces upward and outward is formed.
Also, the knockout 28 is preferably the inclined working surface 3.
Water that extends horizontally from the outer lower end of 2 and faces upward
A flat working surface 36 is provided.

According to the present invention, first, the bent and raised portion 24 is bent and raised in the blank 21, and when the blank 21 is pressed by the punch 27 and the knockout 28 as described above, the bent and raised portion 24 is moved downward by the punch 27. In the state where the blank 21 is pressed and maintained, the central portion of the main plane portion of the blank 21 is formed to be bulged upward by the knockout 28, and as a result, the bent and raised portion 24 is maintained without a large decrease in wall thickness, A U-shaped section is formed on the peripheral edge of the main plane section, and the curved portion of the U-shaped section is press-molded by the knockout 28, and the outer section of the U-shaped section is compression-hardened. As a result, the bent and raised portion 24 remains as an outer portion having a U-shaped cross section that is thicker than in the conventional case. This enables the advantage of the invention, the strength against crimping pressure.

In a preferred embodiment of the present invention, the song
The thickness of the lower raised portion 24 can be the increase depending on the desired. That is, in the preferred embodiment, the inner peripheral side 33b at the lower end of the peripheral edge portion 33 having a U-shaped cross section, a part of which is formed by the bent and raised portion 24, by the action of the inclined action surface 32.
Is biased toward the outer peripheral side 33a. Then, as described above, a part of the meat on the inner peripheral side 33b has moved to the outer peripheral side 33b.
The a is further compressed between the horizontal working surface 29 a of the punch 27 and the horizontal working surface 36 of the knockout 28. As a result, a wall thickness that can sufficiently oppose the force in the A direction, which is the maximum stress applied during crimping, is achieved. further,
It is possible to sufficiently withstand a force in the B direction that is secondarily applied during crimping.

Further, in the preferred embodiment of the present invention , work hardening occurs in the peripheral portion 33 having a U-shaped cross section, particularly on the outer peripheral side 33a, due to the mutual pressing of the punch 27 and the knockout 28 described above. It should be noted. Further, it should be noted that, on the inner peripheral side 33b, the inclined surface 30 formed along the inclined action surface 32 of the knockout 28 exhibits a function as a rib with excess thickness. The processing effect and the rib effect act mechanically favorably with respect to the caulking. Also, in terms of leakage prevention,
That is, the work hardening and the rib effect described above are also advantageous in terms of the adhesion to the packing 7 (FIG. 1).

Further, according to a preferred embodiment of the present invention.
For example, the horizontal working surface 29a of the punch 27 acts on the tip of the bent and bent portion 24 to ensure that the upward horizontal surface 37 is formed there. Further, the horizontal action surface 36 of the knockout 28 acts on the lower end portion of the outer peripheral side 33a of the bent and bent portion 24, and forms the downward action surface 38 there.
Then, from the outer peripheral end of the upward acting surface 37 to the downward horizontal surface 3
An outer vertical surface 39 is formed by extending to the outer peripheral edge of 8. Therefore, the upward horizontal surface 37 and the outward vertical surface 39
At a position where and intersect, an edge 40 protruding relatively sharply
And a downward horizontal surface 38 and an outward vertical surface 3 are formed.
At a position where 9 and 9 intersect, a relatively sharp protruding edge 4
1 is formed. These edges 40 and 41 bite into the packing 7 (FIG. 1) and further contribute to liquid leakage prevention.
That is, since each of the edges 40 and 41 strongly meshes with the packing 7 along each line extending over the entire circumference on the inner peripheral surface of the packing 7, the rising of the electrolytic solution is difficult to be stopped.

FIG. 14 shows the effect of the preferred embodiment of the present invention .
The test method carried out to confirm With reference to FIG. 14, the cathode can 5 obtained by the conventional method and the cathode can 5 obtained by the method of the present invention are each provided with a jig 34.
It is held by and placed vertically. Then, from the top, the pressurizer 35
And the maximum compressive load at the time of primary buckling was measured. When the average value of the values measured for five samples by this method was calculated, the value of the conventional one was 16.6 kg, whereas that of the present invention was 17.25 kg, which is excellent. I understood it.

Further, when the hardness of each portion of the conventional one and the one according to the present invention was measured, the following results were obtained. That is, with a Vickers hardness tester, the Vickers hardness was obtained for each of the portions a to e in FIGS. 9 and 13 under the measurement conditions of a load of 200 grams and a duration of 15 seconds. According to this, in 1a, the conventional one is 208, in the present invention 205, and in 1b, the conventional one is 2.
96, this invention is 353, 1c is conventional, 306, this invention is 38
1, in 1d the conventional one is 369, in the present invention it is 446 and in 1e the conventional one is 3
The result obtained is 69 and that of the present invention is 420. As a result, it is confirmed that work hardening occurs particularly in the peripheral portion 33 having a U-shaped cross section.

In the above-described embodiment, the outer vertical surface 39 extending straight in the vertical direction is formed on the outer peripheral side 33a of the peripheral portion 33 having a U-shaped cross section. Moreover, with this outward facing vertical surface 39, as compared with the conventional outer peripheral side 6a (FIG. 9) which is formed by extending from the curved portion 6c in the natural curved state, the vertical dimension of the surface that extends straight. Can be made longer. This outward facing vertical surface 39 is an important portion for ensuring the close contact with the packing 7 when the anode can 1 is swaged in the direction A (FIG. 13) during the swaging operation, and this is the vertical direction. The longer it leaks
Consisting of liquid to and child prevention. According to the preferred embodiment of the present invention, it is easy to further form the outward vertical surface 39 extending straight in the vertical direction as described above.

[0029]

As described above, according to the present invention, the peripheral edge of a blank having a predetermined size is first bent and bent to one side to form an outer portion having a U-shaped cross section, and then the bent and bent outer surface. The central portion of the blank main plane portion swells while pressing the tip of the portion and the central portion of the main plane portion of the blank against each other and keeping the bent leading end of the outer portion directed toward one side. By being exposed, a peripheral edge portion having a U-shaped cross section is formed at the peripheral edge of the central portion of the main plane portion of the blank and the cross section U is formed.
Since the step of press-molding the curved portion having a U-shape and compressing and hardening the outer portion having a U-shaped cross section is used, the reduction in wall thickness due to the processing of the outer portion having a U-shaped cross section in the related art is suppressed, and as a result, the conventional In comparison, the wall thickness of the outer peripheral half of the U-shaped cross section, in particular, can be made thicker and harder than in the conventional case.

Further , according to the lid of the battery case of the present invention,
For example, the outer half of the U-shaped peripheral edge is
As it is made thick, it is suitable for the load applied during crimping.
And can withstand it enough. Therefore, strong enough
The caulking can be done once, so a more secure seal
Enables realization of the structure and works effectively to prevent electrolyte leakage
To do.

As described above, the present invention makes effective use of the limited volume of the lid by improving the cross-sectional shape of the lid of the battery case of the so-called button type battery having a small size. This is intended to improve strength and liquid leakage resistance.

The present invention is not limited to the silver oxide battery, but is equally applicable to the lid of a battery battery case such as a silver peroxide battery, a mercury battery, a lithium battery, a sealed nickel-cadmium battery, and an alkali-manganese dry battery. Applicable.

[Brief description of drawings]

FIG. 1 is a front view in half section showing a conventional silver oxide battery for explaining an interesting prior art of the present invention.

FIG. 2 is a central vertical cross-sectional view sequentially showing the manufacturing process of the lid of FIG.

FIG. 3 is a central vertical cross-sectional view sequentially showing the manufacturing process of the lid of FIG.

FIG. 4 is a central longitudinal cross-sectional view sequentially showing the manufacturing process of the lid of FIG.

5A and 5B are central longitudinal cross-sectional views sequentially showing the manufacturing process of the lid of FIG.

FIG. 6 is a central vertical cross-sectional view sequentially showing the manufacturing process of the lid of FIG.

FIG. 7 is a central vertical cross-sectional view sequentially showing the manufacturing process of the lid of FIG.

FIG. 8 is a central vertical cross-sectional view sequentially showing the manufacturing process of the lid of FIG.

FIG. 9 is an enlarged view of a peripheral portion of the lid.

FIG. 10 is a central longitudinal cross-sectional view showing sequentially the steps included in the step of manufacturing the lid of the battery container according to the embodiment of the present invention.

FIG. 11 is a central longitudinal cross-sectional view sequentially showing the steps included in the step of manufacturing the lid of the battery case according to the embodiment of the present invention.

FIG. 12 is a central longitudinal cross-sectional view showing sequentially the steps included in the step of manufacturing the lid of the battery case according to the embodiment of the present invention.

FIG. 13 is an enlarged view of the process of FIG.

FIG. 14 shows a test method carried out to confirm the effect of the present invention.

[Explanation of symbols]

 1: Anode can (main body) 5: Cathode can (lid) 7: Packing 30: Inclined surface 33: Peripheral part of U-shaped cross section 33a: Outer peripheral side 33b: Inner peripheral side 37: Upward horizontal surface 38: Downward horizontal surface 39: Outer Orientation Vertical surface 40, 41: Edge

Claims (2)

[Claims] 1. A lid of a battery case holder having a U-shaped peripheral edge portion which engages with the body via a packing when the opening edge of the body of the battery case holder is crimped inward. The peripheral portion of the U-shaped cross section bends to one side from the central portion of the battery case and forms an inner half of the peripheral portion of the U-shaped cross section, Has a cross-sectional shape that further bends to the other side to form an outer half of the U-shaped cross-section peripheral edge, and the U-shaped cross-section circumferential edge corresponds to the outer half of the U-shaped cross section. Is bent and raised from the blank to the other side, and the front end of the bent outer half of the blank is directed and pressed toward the one side, and the central portion of the main plane part of the blank is pressed and directed toward the other side. And the central part of the main plane part of the blank is on the other side By bulging, the peripheral edge portion having a U-shaped cross section is formed at the peripheral edge of the central portion of the main plane portion of the blank, and the tip end portion of the bent outer half of the blank faces the one side. A lid for a battery case, wherein the curved portion having a U-shaped cross section is pressed and formed on the other side in a state where the pressing is maintained. 2. A lid of a battery case holder having a U-shaped peripheral edge portion which engages with the body via a packing when the open end of the battery case body is crimped inward. In the manufacturing method according to claim 1, the peripheral portion having a U-shaped cross section is bent to one side from a central portion of the battery case to form an inner half of the peripheral portion having the U-shaped cross section. A step of preparing a blank that has a U-shaped peripheral portion that is bent to the other side to form an outer half of the U-shaped peripheral portion and that is cut according to the size of the lid to be obtained; Bending a portion of the periphery of the blank corresponding to the outer half of the U-shaped cross section to the other side,
A portion of the peripheral edge of the blank corresponding to the outer half of the U-shaped cross section is bent and raised, and the outer circumference of the blank is defined by a die, while the bent and raised U-shaped cross section is defined. A punch having an action surface for pressing the tip portion of the portion corresponding to the outer half toward the one side, and a region smaller than the peripheral portion having the U-shaped cross section in the central portion of the main plane portion of the blank and in the other side. A step of pressing the blank in a direction intersecting with the main plane portion by a knockout having a central action portion that presses in the direction, the action surface facing the one side of the punch and the other side of the knockout. Due to the mutual pressing with the facing central working part, the main plane part of the blank has the cross section U
By bulging to the other side with respect to the outer half of the character shape, the peripheral edge portion having the U-shaped cross section is formed at the peripheral edge of the central portion of the main plane portion of the blank, and the tip end of the bent outer half portion is formed. A method of manufacturing a lid for a battery case, wherein the curved portion having a U-shaped cross-section is pressed and formed on the other side while the portion is pressed and maintained on the one side.