JP2002239739A - Method of manufacturing metallic vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method which is capable of manufacturing a metallic vessel which is made smaller in its size and weight in manufacturing of the metallic vessel by joining plural vessel members formed with flanges by roller seam welding. SOLUTION: The outer peripheral parts of the flanges 11 an 21 are subjected to roller seam welding while the outer peripheries of the flanges are restrained in view of phenomena, like excessive deformation and crack caused by receiving tensile stress in these outer peripheral parts in roller seam welding. The valve metallic vessel of a small flange width can be manufactured even if such laborious means of cutting the outer peripheral parts of the flanges after welding are not adopted. More preferably, the remaining portions 13 and 23 of the metallic plate material cut from the flanges are left as the annularly continuous portions on the outer peripheries of the flanges and the outer peripheries of the flanges are restrained by these remaining portions 13 and 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a metal container formed by joining a plurality of container members, and more particularly, to an improvement in the joining method.

[0002]

2. Description of the Related Art There are various types of containers formed by joining metal plate-like materials such as steel plates, and they are used in various fields. For example, many are formed by joining container members in the shape of a half container (such as a half of a hollow container), and an automobile fuel tank as shown in FIG.
It is formed as such. Vehicle fuel tank 1 shown
Is a flange made of steel plate or the like at the opening by pressing or the like.
It is general that a semi-container-shaped container member 10 or 20 having 1, 21 is formed, the flanges 11 and 21 thereof are overlapped, and the portions are joined to form a hollow container. Roller seam welding is preferably used for joining the flange portions at this time.

[0003] Roller seam welding is a type of resistance welding, and in the case of joining the fuel tank for an automobile, as shown in FIG. 6, a flange overlapped between two rotating disk-shaped roller electrodes 41 and 42 is used. The flanges 11 and 21 are joined to each other by passing electricity through the roller electrodes 41 and 42 while pressing and holding the roller electrodes 41 and 42 in the thickness direction. Roller seam welding is preferably used for lap joining of thin plates, and has the advantages of high joining strength and excellent sealability at the joint.

However, in the case of the above-described fuel tank for automobiles, the roller electrodes 41 and 42 are connected to the container walls 12 and 22.
In order to avoid interference with the flanges, the flanges 11 and 21 serving as joints thereof need to have a certain width. At the time of welding, the portion of the flange where the seam S is formed tends to expand by being heated. However, since the seam S is constrained by both sides, a compression stress is generated in the seam S, and a tensile stress is generated as a reaction force on both sides of the seam S. The inner periphery I of the flanges 11, 21 is supported by the container walls 12, 22, while the outer periphery O is free of such support, resulting in excessive deformation and, ultimately,
Phenomena such as cracks are likely to occur. Therefore, in order to prevent such excessive deformation and cracking, it is necessary to perform roller seam welding at a position sufficiently distant from the outer peripheral end of the flange.

Further, in the case of roller seam welding, since the portion where the seam S is formed by the roller electrode is strongly compressed in the thickness direction, the tensile stress applied to the outer peripheral portion O of the flange during welding is smaller than that of other welding methods. It becomes extremely large. Therefore, the metal container to which the flange is joined by roller seam welding has a disadvantage that the flange must be formed quite wide.

[0006]

When the flange is formed wide, the outer shape of the container becomes larger and the container becomes heavier than the internal capacity.
For example, in the case of an automobile fuel tank or the like that is installed in a narrow space, the presence of a flange portion that protrudes widely imposes great restrictions on design and makes it impossible to reduce the weight, which is the original goal of the automobile.

[0007] In order to reduce the outer shape of the container and to reduce the weight, it is conceivable to remove the outer peripheral portion of the flange by press cutting or machining after roller seam welding. However, applying such processing to the outer peripheral portion of the flange of the molded container complicates the manufacturing process,
Also, spending a lot of time on it results in increased container manufacturing costs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of a metal container which is joined by roller seam welding a plurality of container members each having a flange, and has been made smaller and lighter. It is an object to provide a manufacturing method capable of manufacturing a container at low cost.

[0009]

(1) A method for manufacturing a metal container according to the present invention is a method for manufacturing a metal container formed by joining a plurality of container members. A container member forming step of forming a container member having a flange integrally formed with a metal plate material, and the flanges of the two container members are overlapped, and the portion is subjected to roller seam welding. A joining step of joining, wherein the joining step performs joining while restraining the outer periphery of at least one of the overlapped flanges in order to suppress expansion of the outer periphery of the flange.

In other words, in the manufacturing method of the present invention, in consideration of the fact that the outer peripheral portion of the flange is subjected to tensile stress during roller seam welding and excessive deformation or cracking occurs, the outer periphery of the flange is restrained. This prevents or suppresses the occurrence of the phenomenon. In other words, for example, when the outer peripheral portion of the flange is stretched by roller seam welding, by creating a state in which an external force is applied so as to suppress this stretching, the above-described phenomenon such as excessive deformation and cracking is caused. Prevention and suppression.

The specific means is not particularly limited, and the outer peripheral portion of the flange may be restrained by a jig or the like. For example, an annular rigid body whose inner periphery is substantially equal to the outer periphery of the flange is fitted to the outer periphery of the flange, that is, a roller shim with the flange fitted in a jig having an inner periphery that exactly fits the entire flange. Welding may be performed.
Alternatively, for example, roller seam welding may be performed in a state where something is wound and the outer periphery of the flange is tightened. In other words, the two modes exemplified are modes in which roller seam welding is performed in a state where a hoop is fitted on the outer periphery of the flange.

Since the roller seam welding is performed by overlapping the flanges, only one of the flanges is restrained, and both of the flanges to be overlapped are restrained. However, from the viewpoint of more surely suppressing the expansion of the flanges, it is desirable to restrain the outer circumferences of both flanges to be overlapped.

As described above, by performing roller seam welding while restraining the outer periphery of the flange in order to suppress expansion of the flange, roller seam welding in which a seam is formed near the outer periphery of the flange becomes possible. As a result, a metal container having a small flange width can be manufactured without using a complicated means such as cutting the outer peripheral portion of the flange after welding. Therefore, in the manufacture of a metal container that is joined by roller seam welding a plurality of container members formed with a flange, the manufacturing method of the present invention is more compact,
The manufacturing method can manufacture a lightweight metal container at low cost.

Not only a metal container formed by joining two container members, but also a metal container formed by joining three or more container members, The manufacturing method of the present invention can be applied to bonding. Further, the flange does not necessarily have to be annular, and may be a flange having a part that is not continuous.

(2) In the method of manufacturing a metal container according to the present invention, in the container member forming step of forming at least one container member, the flange is formed by cutting an outer periphery, and the cut metal is formed. The remaining portion of the plate-shaped material is formed in an annular shape, and the container member is formed so that the remaining portion remains in a state where the flange is fitted into the inner periphery thereof. In the joining step, the remaining portion forms the outer periphery of the flange. It is possible to carry out in such a manner as to restrict.

When the container member is formed from a metal plate material, for example, when the container member is formed from one metal plate material, the material is subjected to sheet metal processing such as pressing. It is common to form a container wall and a flange integrally formed on the container wall. In this case, the flange is generally formed to be wide and then cut so as to have a predetermined outer peripheral shape. In that case, the cut material is scrap (waste material)
Becomes

In the manufacturing method of this aspect, in such a container member forming step, the cut material, more specifically, the remaining portion of the cut metal plate-like material is formed into one annularly continuous scrap. Cut the outer circumference of the flange.
Then, the annular scrap is left so as to surround the outer periphery of the flange. That is, the flange is fitted into the inner periphery of the annular scrap. Specifically, for example, using two molds capable of sandwiching a metal plate-shaped material and providing an appropriate clearance, and holding the materials in the molds, the molds are mutually moved in the thickness direction. Shearing is performed by shifting the mold, and then the molds are returned to their original positions. After that, when the material is released, the remaining cut portion, that is, the annular scrap remains on the outer periphery of the flange. That is, a method of so-called push-back after cutting may be adopted.

In the manufacturing method of this embodiment, in the joining step, the flanges of the two container members are overlapped with each other while the annular scrap remains, and roller seam welding is performed. During welding, when the flange tries to expand its outer circumference, it acts to tighten the outer circumference, and as a result, the annular scrap restrains the outer circumference of the flange, so that the expansion of the outer circumference of the flange is suppressed, and Phenomena such as excessive deformation and cracking are prevented and suppressed.

According to the manufacturing method of this aspect, the remaining portion obtained by cutting the flange, which becomes scrap, that is, the material to be discarded, serves as the flange restraining means in the joining step. It becomes possible. Also, no special equipment is required for leaving the annular scrap on the outer periphery of the flange, and the container member forming step can be performed extremely simply. Furthermore, in the state where the roller seam welding is completed and the temperature of the flange is lowered, the outer circumference of the joined flange is reduced, and the annular scrap, which had been in the state of tightening the flange at the time of welding, easily comes off the flange. No special equipment or means is required for removing the annular flange.

In the manufacturing method of the present embodiment, the annular scrap may be left on the outer periphery of at least one flange of the two container members to be joined. As described above, merely restricting one flange restricts both of the overlapping flanges. However, as described above, from the viewpoint of more reliably suppressing the expansion of the flange, it is desirable to restrain the outer circumferences of the two overlapping flanges. It is desirable to retain the annular scrap.

(3) In the method for producing a metal container of the present invention, the kind of the metal is not particularly limited. For example, as long as the container member can be formed from a plate-shaped material such as carbon steel, stainless steel, and an aluminum alloy and the metal can be used for roller seam welding, the present invention can be applied to the production of various metal containers. Steel can be selected as a practical container material, but stainless steel has a higher thermal expansion coefficient than carbon steel but has a low thermal conductivity, so excessive deformation and cracking during welding are not likely to occur. The possibilities are great. In view of this, the method for manufacturing a metal container according to the present invention is a more effective method when the metal plate material is a stainless steel plate and applied to the manufacture of a stainless steel container.

(4) The metal container to which the production method of the present invention is applied is not particularly limited in its use, but is intended for containers used for various uses. Among various containers, the fuel tank for automobiles is limited by its shape in that it is installed in a narrow space, and it has significant restrictions in its design such as the need for lighter weight. The method for producing a metal container described above is extremely effective when provided for producing a fuel tank for an automobile.

In addition, there is a trend to replace carbon steel plates with stainless steel plates in order to improve the durability of automobile fuel tanks. In the case of a stainless steel tank, the press formability of the container member is inferior, so that the tank shape is greatly restricted in manufacturing. Therefore, in addition to the functional restriction of being installed in a small space, the internal capacity of the device often has to be reduced. Therefore, the effect of the manufacturing method of the present invention that the flange width can be reduced can be exerted without any particular problem when applied to the manufacture of a fuel tank for a stainless steel automobile.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a method for manufacturing a metal container of the present invention will be described in detail in the order of a container member forming step and a joining step, taking a case of a stainless steel automobile fuel tank as an example. The stainless steel automobile fuel tank to be manufactured has the shape shown in FIG. This fuel tank is composed of two semi-container-shaped container members, an upper container member 11 and a lower container member 20.
Numeral 0 has flanges 11 and 21, respectively. The flanges 11 and 21 are overlapped with each other, and the portions are joined by roller seam welding to form a hollow container.

<Container Member Forming Step> In the container member forming step, a container member having a container wall and a flange formed integrally with the container wall is formed from a metal plate material. FIG. 2 schematically shows how a container member is formed by a press device. In the container forming step of the present embodiment, the container members 10 and 20 are drawn and formed from a stainless steel plate using a mold. The press die 30 includes an upper die 31 and a lower die 32. The upper mold 31 is formed into a central upper mold 31a having a mold shape along the inner wall surface and the flange of the container member, and an annular outer upper mold 31b positioned around the central upper mold 31a to press the outer periphery of the flange of the container member. It is divided and can move up and down independently. Similarly, the lower mold 32 is
A central lower mold 32a shaped along the outer wall surface and the flange of the container member, and an annular lower peripheral mold 32b positioned around the central lower mold 32a for pressing the outer periphery of the flange of the container member
And can move up and down independently.

First, as shown in FIG.
Inside, a stainless steel plate 40 cut into a predetermined size and shape is set. Next, as shown in FIG. 2B, the outer peripheral upper die 31b moves downward, and the stainless steel plate 4
0 is sandwiched between the upper outer die 31b and the lower outer die 32b. This pinching is not so firm that the stainless steel plate 40 does not move, but is such that it can slide between the two dies in the subsequent drawing process, and acts as a wrinkle holder.

Next, as shown in FIG. 2C, the upper central mold 31a moves downward, and the stainless steel plate is drawn by the lower central mold 32a. As a result, the container wall 12
(22) and the flange 11 (21) are formed, and in this state, the surplus portion of the stainless steel plate, that is, the remaining portion 13 (23) remains integrally on the outer periphery of the flange 11 (21).

Next, as shown in FIG. 2D, the container wall 12 (22) and the flange 11 (21) are
1a and the lower central mold 32a, and the remaining portion 13 (23) of the stainless steel plate is fixed to the upper outer mold 31b and the lower outer mold 32.
b and the outer peripheral upper mold 31b and the outer peripheral lower mold 3
2b is moved with respect to the upper center mold 31a and the lower center mold 32a, and the remaining portion 13 (23) is cut from the flange 11 (21). That is, the upper central mold 31a and the outer peripheral mold 31b
A predetermined clearance is provided between the lower mold 32a and the lower mold 32a and the outer mold 32b.

Thereafter, as shown in FIG.
The container wall 12 (22) and the flange 11 (21) are sandwiched between the upper central mold 31a and the lower central mold 32a, and the remaining portion 13 (23) of the stainless steel plate is sandwiched between the outer peripheral upper mold 31b and the outer peripheral mold 32b. The upper outer mold 31b and the lower outer mold 32b are moved with respect to the upper middle mold 31a and the lower middle mold 32a, and the flange 11 (21) is flush with the cut remaining portion 13 (23) of the stainless steel plate. Back to the right position. In other words, the mold is pushed back,
The remaining portion is left at the position before cutting.

After the above process, the container member forming step of this embodiment is completed. FIG. 3 shows the formed container member. FIG. 1 shows an upper container member 10 in the vehicle fuel tank 1 shown in FIG. The upper container member 10 has a container wall 11 and a flange 11 formed integrally with the container wall 12.
Remaining portion of cut stainless steel plate (annular scrap) 1
3 remain, and the annular scrap 13 is annularly continuous. In other words, annular scrap 13
Remains in a state where the flange is fitted on the inner periphery thereof. It can be described as if a wide flange is formed and the flange has an annularly continuous cut C.

In the above-described container forming step, the flange is once completely cut, and the cut remaining portion is restored. Instead of cutting completely,
Partially cut state (state where part of the plate thickness remains connected)
In this case, a push-back method, that is, a so-called counter blanking method can be employed. Also,
It is also possible to leave the annular scrap on the outer periphery of the flange by adopting a method of flat pressing the half-cut state with another mold or the like.

<Joining Step> In the joining step, the respective flanges of the two container members are overlapped, and the portions are joined by roller seam welding. FIG. 4 shows a state in which the flange is subjected to roller seam welding in the joining step of the present embodiment, and FIG. 5 shows a cross section of the joined portion.
FIG. 5B is an enlarged view of the vicinity of the boundary between the flange and the annular scrap in FIG. 5A.

In the main joining step, the upper container member 10 and the lower container member 20 formed in the container member forming step are overlapped with the flanges 11 and 21 so that their outer peripheries coincide. In other words, the annular scraps 13 and 23 are superimposed together while remaining. In other words, the upper container member 10 and the lower container member 20 are overlapped so that the cuts C are aligned.

Then, the overlapped flanges 11 and 21 are pressed and sandwiched between two roller electrodes 41 and 42 to perform roller seam welding. A predetermined welding current is applied between the roller electrodes 41 and 42, the portions sandwiched between the electrodes are melted and softened, and the roller electrodes are solidified after moving, and the flanges 11 and 21 are fixed. A seam S is formed behind the roller electrodes 41 and 42 after the roller electrodes 41 and 42 have moved.
The joining is completed when 1, 42 makes one round.

In the main joining step, the annular scrap 1
Since the roller seam welding is performed with the portions 3 and 23 remaining, the annular scraps 13 and 23 restrain the outer circumferences of the flanges 11 and 21 during welding. That is, flange 1
The welding is performed with the hoops fitted on the outer circumferences of 1, 21. Therefore, when the flange, particularly its outer peripheral portion is to be elongated by welding, a state is such that a reaction force is applied from the outside so as to suppress this elongation,
Prevent and suppress phenomena such as excessive deformation and cracking.

From this, the seam S is formed by the flange 1
1, 21 can be formed in the vicinity of the outer periphery, that is, the vicinity of the outer periphery can be welded.
Can be formed to have a small width. Compared with FIG. 6 showing the state of roller shim welding in the conventional manufacturing method, in the roller seam welding of the main joining step shown in FIG. It is easy to see that the distance to) is small. In this embodiment, when the roller seam welding is completed and the temperature of the flanges 11 and 21 is lowered, the outer circumferences of the joined flanges 11 and 21 are reduced, and the flanges 11 and 21 are tightened at the time of welding. The existing annular scraps 13 and 23 easily come off the flanges 11 and 21.

<Allowance of Other Embodiments> The embodiment of the method for manufacturing a metal container of the present invention has been described above. However, the method for manufacturing a metal container of the present invention is not limited to the above embodiment. Rather, the present invention can be implemented in various modes with modifications and changes that can be made by those skilled in the art, including the above-described embodiment.

[0038]

According to the present invention, in the manufacture of a metal container in which a plurality of container members each having a flange formed thereon are joined by roller seam welding, the outer peripheral portion of the flange is subjected to tensile stress during roller seam welding and excessively deformed. In view of the occurrence of phenomena such as cracks and the like, the occurrence of these phenomena is prevented or suppressed by restricting the outer periphery of the flange.
As a result, a metal container having a small flange width can be manufactured without using a complicated means such as cutting the outer peripheral portion of the flange after welding, and therefore, the manufacturing method of the present invention is further reduced in size and weight. This is a method of manufacturing a metal container at low cost.

[Brief description of the drawings]

FIG. 1 shows a fuel tank for a stainless steel automobile to be manufactured in an embodiment of the present invention.

FIG. 2 schematically illustrates how a container member is formed by a press device in a container member forming step according to an embodiment of the present invention.

FIG. 3 shows a container member formed in a container member forming step of the embodiment of the present invention.

FIG. 4 shows a state in which a flange portion is subjected to roller seam welding in the joining step of the embodiment of the present invention.

FIG. 5 shows a cross section of a bonding portion in a bonding step according to the embodiment of the present invention.

FIG. 6 shows a cross section of a bonding portion in a bonding step of a conventional manufacturing method.

[Explanation of symbols]

 1: Fuel tank for automobile (metal container) 10: Upper container member 20 Lower container member 11, 21: Flange 12, 22: Container wall 13, 23: Annular scrap (remaining cut) 30: Press die 31: Upper die 32: Lower die 31a: Upper center die 31b: Upper outer die 32a: Lower center die 32b: Lower outer die 41, 42: Roller electrode C: Cut S: Seam

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) F02M 37/00 301 B23K 101: 12 // B23K 101: 12 B60K 15/02 A

Claims (4)

[Claims] 1. A method for manufacturing a metal container formed by joining a plurality of container members, wherein the container member having a container wall and a flange formed integrally with the container wall is formed in a metal plate shape. A container member molding step of molding from a material; and a joining step of superimposing the flanges of the two container members and joining the portions by roller seam welding. A method for manufacturing a metal container, wherein joining is performed while restraining the outer circumference of at least one of the overlapped flanges to suppress expansion of the outer circumference. 2. The container member forming step of forming at least one container member, wherein the flange is formed by cutting an outer periphery, and the remaining portion of the cut metal plate-like material forms an annular shape, and the remaining portion is formed. 2. The manufacturing of a metal container according to claim 1, wherein the container member is formed such that the resin member remains in a state where the flange is fitted to the inner periphery thereof, and the remaining portion restrains the outer periphery of the flange in the joining step. Method. 3. The method according to claim 1, wherein the metal plate material is a stainless steel plate, and the stainless steel container is manufactured. 4. A fuel tank for an automobile is manufactured.
A method for producing a metal container according to claim 3.