JPH09298056A - Molding method for collecting terminal for storage battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a collecting terminal having a protruded part which is substantially perpendicular to a plate part manufactured by cold forging or warm forging, and a manufacturing method thereof. SOLUTION: A thin diameter end of a material member 7 is inserted into a cavity 21 provided in a lower die 11. An upper die 12 is then engaged with a cavity 22 provided in the lower die 11, and the upper die 12 is moved in an arrow direction by a pressurizing mechanism of a cold forging press for pressure-deforming the material member 7 to fill material in the cavity 22 to be formed to be a product. The material is nickel or nickel alloy, and it is possible that heat treatment is not applied in a molding process. A collecting terminal for a storage battery of excellent mechanical characteristics can thus be provided, mechanical work cost can be largely reduced, material cost can be reduced, and product weight can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current collector for a storage battery, which has protrusions that are substantially perpendicular to a plate-like portion by cold forging or warm forging a metal material having excellent conductivity. The present invention relates to a method of molding a terminal.

[0002]

2. Description of the Related Art A terminal having protrusions which are substantially perpendicular to a plate-like portion, for example, a current collector terminal for a sealed storage battery,
Since it is made of metal, the plate-shaped part has large vertical and horizontal dimensions compared to the thickness of the protruding part, and the thickness is thin, so conventionally, the protruding member is welded to the metal plate-shaped member or the precision casting method is used. The method of integrally molding by the hot forging method has been adopted. But,
Welded products and cast products had problems in stability of mechanical strength and soundness of structure.

If the projection and the plate-like portion are integrally formed by forging, the problems of stability of mechanical strength and soundness of tissue can be avoided. However, conventional forging methods, such as upset forging, make it difficult to manufacture a plate-shaped part having a larger dimension than the protrusion, and it is extremely difficult to manufacture a plate having an asymmetrical shape. It was Further, in the case of die forging, it is difficult to avoid the formation of burrs, so that there is a problem that the material yield is reduced.

An attempt is made to manufacture a metal part, such as the above-mentioned current collector terminal for a sealed type storage battery, in which the plate-shaped portion has a large vertical and horizontal dimensions with respect to the thickness of the protrusion and the thickness is thin by the conventional forging method. In this case, it is necessary to perform hot working such as hot forging, and it is difficult to obtain a product having good mechanical strength, dimensional accuracy, and surface quality. For example, 3-76
In the one disclosed in Japanese Patent Laid-Open No. 360, a triangular reinforcing portion is provided to reinforce bending due to insufficient strength of the protrusion and the plate-like portion, or a slit portion is machined after forging to secure dimensional accuracy. Had to do.

The current collecting terminal is required to have excellent conductivity, and further, it is required to have corrosion resistance against an alkaline solution used as an electrolytic solution. In order to satisfy these requirements, nickel or nickel alloy is conventionally used, and it is manufactured into a current collector terminal by a method such as shaving from a bar material or a precision casting method. The collector terminal is fixed to the battery case by a nut screwed into the mounting screw portion. To ensure the retention of the electrodes and prevent leakage of the electrolyte,
Since the nut is tightly tightened, a large tensile force acts on the mounting thread. Therefore, in the current collector terminal made of nickel or nickel alloy manufactured by the conventional method as described above, inconvenience such as breakage of the screw portion may occur.

If the size of the current collector terminal is increased in order to improve the strength of the threaded portion, the weight of the component is increased and the usefulness as a power source for transportation is impaired. In addition, there is a problem that when the alloy is alloyed to improve the strength, the conductivity of the material is lost.

[0007]

SUMMARY OF THE INVENTION In view of the above-mentioned situation, the problem to be solved by the present invention is to provide a projection which is formed by cold forging or warm forging at a right angle to the plate-shaped portion. It is to provide a method of molding a collector terminal for a storage battery having a portion.

[0008]

In order to solve the above-mentioned problems, the method of molding a collector terminal for a storage battery according to the present invention comprises: (1) Protrusions that are substantially perpendicular to each other with respect to a plate-like portion. When the current collector terminal for a storage battery is formed by cold forging or warm forging, the end face shape of the terminal is matched with the cavity of the first mold having the cavity for forming the plate-like portion and the protrusion of the terminal. A second mold having an end surface for sliding and engaging with the cavity,
Between the cavity provided in the first die and the second die by compressing and deforming the material inserted in the cavity forming the protrusion of the terminal provided in the first die by moving the die of the first die. It is characterized in that it is filled with a material and molded. (2) In the method for forming a storage battery current collector terminal described in (1), the material is made of any one of nickel and nickel alloys. (3) In the method of molding a current collector terminal for a storage battery according to (1), the plate-shaped portion and the protrusion portion are provided with a hollow lightening portion. (4) In the method of molding a current collector terminal for a storage battery according to (1), the side surface of the plate-shaped portion is provided with an electrode plate connecting portion in a direction perpendicular to the protruding portion. (5) In the method of molding a current collector terminal for a storage battery according to (1), the electrode plate connecting portion is provided in a direction opposite to the protruding portion of the plate-shaped portion. (6) In the method of molding a current collector terminal for a storage battery according to (1), the heat treatment is not performed during the molding step. (7) In the method for molding a current collector terminal for a storage battery according to (1), the hardness of the protrusion is 190 to 370 HV.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the method for molding a collector terminal for a storage battery of the present invention, the terminal is manufactured by cold forging or warm forging. Warm forging is preferably performed at a temperature of 600 ° C or lower. As a result, the heating scale does not adhere to the surface of the product, and the surface quality and dimensional accuracy of the product can be improved.

In the method of molding the current collecting terminal for the storage battery of the present invention,
The material to be processed is inserted into the cavity forming the protrusion of the first mold. At this time, if the gap between the material to be processed and the cavity is large, the mounting of the material to be processed becomes unstable. Therefore, it is preferable to fit the material so that there is no rattling. The second mold slides into the cavity of the first mold. Then, it is driven by a separately provided driving device to relatively move the first mold and the second mold, and the second mold is fitted into the cavity provided in the first mold. At this time, the end surface of the second mold comes into contact with the work piece attached to the first mold, and then the work piece is compressed and deformed. further,
When the second mold is moved, the material to be processed is plastically deformed and enters the cavity forming the plate-shaped portion to form the plate-shaped portion.
When the above-mentioned processing is performed, the second mold and the first mold are brought into a sliding state so that the second mold can smoothly enter the first mold cavity. . Then, the unbalanced stress generated when the work material is deformed is supported by the sliding surface between the second mold and the first mold, which enables smooth processing. In particular, this effect is great in a product in which the plate-shaped portion is asymmetric with respect to the protrusion.

Since the end surface of the second mold has a shape that matches the shape of the end surface of the product, the end surface shape of the product is formed.
After the molding is completed, the product may be taken out by a commonly used knockout pin or the like. INDUSTRIAL APPLICABILITY The method for forming a collector terminal for a storage battery according to the present invention can be applied to nickel and nickel alloys which are excellent in conductivity and corrosion resistance to an alkaline solution used as a storage battery electrolyte. As a result, compared with the conventional method of manufacturing a current collector terminal by a method such as shaving from a bar material or precision casting, it is possible to reduce shavings and improve the strength, save the expensive nickel material, and significantly Economic effect is raised.

Further, according to the method of molding the current collecting terminal for a storage battery of the present invention, it is possible to provide the hollow portion in the plate portion and the protrusion. This can save material and reduce weight. Further, according to the method for molding the current collecting terminal for a storage battery of the present invention, the current collecting terminal for a storage battery, which is provided on the side surface of the plate-shaped portion with an electrode plate connecting portion in a direction perpendicular to the protrusion, the protrusion of the plate-shaped portion It is possible to form a collector terminal for a storage battery, which is provided with the electrode plate connecting portion in the opposite direction.

According to the method of molding the current collecting terminal for the storage battery of the present invention, the material to be processed undergoes work hardening in the molding process, so that the material strength is increased. This work hardening disappears when heat treatment such as annealing is applied. In the method of molding the current collecting terminal for a storage battery of the present invention, by not performing heat treatment during the molding step, the material strength can be improved simultaneously with molding.

It is preferable that the hardness of the product, particularly the hardness of the protrusions, is set to 190 to 370 HV by processing without heat treatment during the molding process. The protruding portion forms a mounting screw portion in the storage battery current collecting terminal and generates high stress. Therefore, it is desirable that the hardness is at least 190 HV. However, if it is excessively hardened, processing becomes difficult and the material becomes brittle, so the upper limit of hardness is set to 370 HV.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. One embodiment of the present invention will be described for the case of cold forging pure nickel to manufacture the terminal shown in FIG. The protrusion 1 has a diameter of 8 mm and a length of 10 mm and the protrusion 2 has a diameter of 12 m.
It is composed of m × 6 mm long protrusions 3. The protrusion 3 has a plate-like portion 4 having a square-like plate-like portion 5 having a side of 21 mm and a thickness of 6 mm and a plate-like portion 6 having a thickness of 15 mm × 12 mm × a thickness of 6 mm, which is substantially perpendicular to the protrusion 3 at one end thereof. Equipped with.

In manufacturing the above terminal, a diameter of 1
6 mm x 24.4 mm long pure nickel bar (hardness HR
B68-70), diameter 8 mm × length 10 mm, diameter 12 mm × length 6 mm, side 21 mm ×
A base material 7 including each part having a thickness of 8.5 mm was manufactured.
In this example, the lower mold 11 was used as the first mold. The lower mold 11 includes a cavity 21 for forming the protrusion 1 of the terminal and a cavity 22 for forming the plate-like portion 4. The upper mold 12 slides into the cavity 22 and has an end face matching the end face shape of the terminal. In this embodiment, the upper mold 1
The end face shape of No. 2 was flat.

As shown in FIG. 1, the small-diameter end of the blank 7 is inserted into the cavity 21 forming the protrusion of the lower mold 11.
Then, the upper mold 12 is fitted into the cavity 22 provided in the lower mold 11. By a pressing mechanism of a cold forging press (not shown), the upper die 12 is moved in the direction of the arrow in FIG. 1 to deform the raw material 7 under pressure, and the voids in the cavities 22 are filled with the material to form the terminals into the product shape. .

After the completion of molding, the upper die 12 was moved in the direction opposite to the direction of the arrow in FIG. 1 to remove the upper die 12 from the cavity 22, and then the terminal was taken out by the knockout pin 23. As a result of measuring the hardness of the terminal thus processed, a value of 220 to 250 HV was obtained. From this result, it is recognized that the present invention has the effect of improving the mechanical properties of the material.

The conventional method of manufacturing terminals by using a material such as pure nickel by hot forging, lost wax or cutting from a rod cannot increase the hardness of the terminals beyond the hardness of the material. When it is necessary to increase the hardness of the terminal manufactured by the conventional method, it is necessary to perform cold working on that portion and increase the hardness by work hardening. On the other hand, according to the molding method of the present invention, it is possible to improve the mechanical properties of the terminal while forming the shape of the terminal.

In order to adjust the desired shape or size as necessary, after molding, the product is finished by machining or the like to obtain a final product. In addition, as the material of the terminal, pure nickel is given as an example in the embodiment, but nickel alloy or other metal / alloy having excellent conductivity may be used. Compared to a cut product obtained by finishing the material into the same shape as the final product of this embodiment only by cutting, in the case of this embodiment, the material cost reduction was 82% and the machining cost reduction was 90%.

When the plate-like portion is formed symmetrically with respect to the protrusion, more stable plastic flow can be obtained, and a complicated forged shape such as making a hole in a part of the product is possible. In the example of the present invention, a shaft-shaped hole is formed in the center of the protrusion to reduce the weight of the product and the material cost. The details will be described below with reference to the drawings. One embodiment of the present invention will be described for the case of cold forging pure nickel to produce the terminal with holes shown in FIG. The protrusion 31 is composed of a protrusion 32 having a diameter of 9 mm and a length of 12 mm and a protrusion 33 having a diameter of 17 mm and a length of 7 mm. The protruding portion 33 has a rectangular shape of 35 × 25 mm and a thickness of 3 mm, which is substantially right-angled with the protruding portion 33 at one end thereof and which is substantially symmetrical with respect to the axial center line of the protruding portion 33.
The plate-shaped portion 34 is provided. The plate-like portion 34 has a length of 25 m at one end.
The plate-like portions 35 of m × 2 mm × height of 5 mm are provided symmetrically with respect to the axial center line, one for each and two in total. further,
7 mm diameter along the central axis of the protrusion 33 and the plate-like portion 34
It has a hole-shaped portion 36 having a depth of 6 mm.

FIG. 4 shows a schematic view of a forging process in manufacturing the above terminal. First, the first step is 20m in diameter
An intermediate material 38 having no hole portion 36 was manufactured by upsetting from a pure nickel material 37 of m × length 16 mm. Next, in the second step, a hole-shaped portion 36 is formed in the central portion of the intermediate member 38 by extrusion, and the hole-shaped portion 36 is formed.
A terminal 39 having

FIG. 5 shows an outline of the mold structure in this embodiment. The lower mold 40 was used as the first mold. Lower mold 40
Has a cavity 47 into which the intermediate member 38 is inserted. An upper mold 41 for fixing the inserted intermediate member 38 is provided as a second mold. Further, a punch 43 for extruding and forming the hole-shaped portion 36 is provided as a third mold. The upper die 41 is provided with a slide guide 42 and a punch 4 in order to extract the punch 43 from the product and separate the punch 43 after completion of punching.
Sliding motion is performed for 3. The sliding motion is performed by the upper die 41.
And punch 43, upper die base 45, slide guide 42
This is performed by the restoring force of the spring 44 included between the and.

As shown in FIG. 5, the intermediate member 38 is inserted into the cavity 47 of the lower mold 40. Then, the punch 43 was extruded by moving the punch 43 in the direction of the arrow while fixing the intermediate material 38 with the upper die 41 by a pressing mechanism of a cold forging press (not shown). After molding is completed, upper mold 41
Punch 43 is removed from the product by the sliding motion of
Move in the direction opposite to the arrow and then knock out pin 4
The terminal was taken out according to 6.

As a result of measuring the weight of the processed terminal, a weight reduction of 6% in the material weight and 7% in the product weight was recognized with respect to the terminal having no hole 36.

[0026]

As described above, according to the molding method of the present invention, the projections which are formed by cold forging or warm forging and which have a relatively large area and are substantially perpendicular to each other. A terminal having a portion can be provided. Further, according to the molding method of the present invention, it is possible to obtain a terminal having excellent mechanical properties and high reliability of the soundness of the metal structure, and at the same time, it is possible to significantly reduce the machining cost and the material cost. In addition, the product weight can be reduced, and a great economic effect can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a mold according to an embodiment of the present invention.

FIG. 2 is a perspective view of a terminal according to an embodiment of the present invention.

FIG. 3 is a front view of a terminal having a hole-shaped portion at the center of a protrusion.

FIG. 4 is a schematic view of a forging process in an example of the present invention.

FIG. 5 is a schematic view showing a mold structure according to an example of the present invention.

[Explanation of symbols]

 1, 2 and 3 Protrusions 4, 5 and 6 Plate-shaped part 7 Elemental material 11 Lower mold 12 Upper mold 21, 22 Cavity 23 Knockout pin 31, 32, 33 Projection part 34, 35 Plate-shaped part 36 Hole-shaped part 37 Material 38 Intermediate material 39 Terminal 40 Lower mold 41 Upper mold 42 Slide guide 43 Punch 44 Spring 45 Upper mold base 46 Knockout pin 47 Cavity

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroumi Kajiya 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. Inventor Hisashi Honda 23-27 Kamisanhonmatsu, Honjuku-cho, Okazaki City, Aichi Prefecture

Claims (7)

[Claims] 1. Forming a plate-shaped portion and a protruding portion of the terminal when forming a current collecting terminal for a storage battery having a protruding portion that is substantially perpendicular to the plate-shaped portion by cold forging or warm forging. A second mold having an end face matching the end face shape of the terminal and sliding in the cavity is fitted into the cavity of the first mold including the cavity, and the second mold is moved. By doing so, the material inserted into the cavity forming the protrusion of the terminal included in the first mold is compressed and deformed, and the material is filled between the cavity included in the first mold and the second mold. A method for forming a current collecting terminal for a storage battery, which comprises: 2. The method for molding a current collector terminal for a storage battery according to claim 1, wherein the material is one of nickel and a nickel alloy. 3. The method for molding a current collector terminal for a storage battery according to claim 1, wherein the plate-shaped portion and the projection portion are provided with hollow hollow portions. 4. The method for molding a collector terminal for a storage battery according to claim 1, wherein a side surface of the plate-shaped portion is provided with an electrode plate connecting portion in a direction perpendicular to the protruding portion. 5. The method for molding a collector terminal for a storage battery according to claim 1, further comprising a pole plate connecting portion in a direction opposite to the protruding portion of the plate-shaped portion. 6. The method of molding a collector terminal for a storage battery according to claim 1, wherein heat treatment is not performed during the molding step. 7. The hardness of the protrusion is 190 to 370 HV.
The method for forming a collector terminal for a storage battery according to claim 1, wherein