KR20160046959A

KR20160046959A - Manufacturing method of wheel rim and Wheel rim manufactured thereby

Info

Publication number: KR20160046959A
Application number: KR1020140141737A
Authority: KR
Inventors: 정연일; 권혁선; 이민성; 김돈건
Original assignee: 주식회사 포스코
Priority date: 2014-10-20
Filing date: 2014-10-20
Publication date: 2016-05-02

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an automotive wheel rim and a wheel rim produced thereby, more particularly, to a rim forming step of joining a plate material and forming a rim; And a bead molding step of deforming a cross section of the rim using a roll.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a wheel rim manufacturing method and a wheel rim manufactured thereby,

The present invention relates to a method for manufacturing an automotive wheel rim and a wheel rim produced thereby.

A typical automobile wheel is provided with a rim for maintaining the shape of a tire coupled to the outer periphery, and is composed of a disc coupled to the rim and coupled to the axle to prevent deformation of the rim.

A typical method of manufacturing such an automobile wheel is a method in which a disk and a rim are respectively molded and then joined together by arc welding or the like, or a method mainly used in an aluminum alloy, in which a melted metal such as casting or die- There is a way.

In particular, in the case of an automobile wheel rim, it can be manufactured by a process as shown in Fig. First, the material 1 made of a specific material is prepared, and the material 1 is formed into a plate material 10 of an appropriate size through a process such as blanking.

The joining portion 11 is formed by machining the plate member 10 into a cylindrical shape using the upper die 20 and the lower die 30 or a plurality of rotating rolls 40a and 40b and welding the end portions.

Then, the plate member 10 may be formed as a cylindrical body 12 by connecting ends thereof by welding. The flange (not shown) of the cylindrical body 12 can be expanded by performing a trimming process to remove burrs and performing a flaring process to adjust the dimensions. In addition, in order to process and correct the dimension of the wheel rim, a press process using the upper mold 20 and the lower mold 30 or a roll forming process using a plurality of rolls 40a and 40b may be performed a plurality of times.

Finally, grinding is applied to polish the surface and precise dimension compensation can be used to manufacture automotive wheel rims, which can then be welded together with a specially manufactured disk to form an automobile wheel.

However, in order to improve the strength and durability of an automobile wheel, it is essential to form a bead (not shown) in the wheel rim. At this time, a technique called hydro-forming is commonly used to form beads.

Hydroforming technology is a technology to make a steel plate into a tube shape when making a complex shaped automobile part, and then to produce a final product in a desired shape by applying a strong hydraulic pressure (hydrostatic pressure) into the tube. When this technology is applied, durability It has the advantage of being able to make a light product with 10-20% weight, but it has a disadvantage that the manufacturing cost is large and the working time is very long.

Therefore, it is necessary to study a manufacturing method of a wheel rim that can improve the durability of an automobile wheel, reduce manufacturing cost, and shorten the working time.

KR 10-2008-0009464 A (2008.01.29. Public)

The present invention aims to provide a method for manufacturing an automotive wheel rim having increased durability and a wheel rim produced thereby.

It is another object of the present invention to provide a method for manufacturing an automotive wheel rim that reduces the manufacturing cost by efficiently designing the manufacturing process and shortens the working time, and a wheel rim produced by the method.

According to another aspect of the present invention, there is provided a method of manufacturing a vehicle wheel rim comprising: a rim forming step of joining a plate material and forming a rim; And a bead molding step of deforming the cross section of the rim using a roll.

Preferably, the bead forming step may apply a stamping structure to the surface of the roll to form a bead in the rim.

More preferably, the bead forming step may be performed by a first rotating roll having a shape corresponding to the beads formed on the surface of the first rotating roll, and a second rotating roll having a shape corresponding to the beads formed on the surface of the first rotating roll.

Also preferably, the rim forming step may further include a flanging step of deforming the size or cross-section of the diameter of the rim.

Further, preferably, in the bead forming step, the outer diameter of the roll may be the same as the inner diameter of the rim.

And, preferably, the plate material may be provided with TWIP steel.

On the other hand, the present invention as another aspect provides a wheel rim produced by the method for manufacturing the wheel rim.

According to a preferred embodiment of the present invention, an automobile wheel rim can be manufactured which is simple and efficient in manufacturing process.

Specifically, since a plurality of roll forming or hydroforming steps required for forming beads in the wheel rim can be omitted, it is possible not only to increase the utilization of the material but also to reduce the manufacturing time.

Further, since the bead can be formed through roll stamping on the wheel rim, the durability and strength of the automobile wheel rim can be secured more easily.

In addition, since the wheel rim including the bead can be easily manufactured, there is an effect that the additional process for securing the durability and strength of the automobile wheel rim can be omitted.

As a result, it is possible to reduce not only the cost of manufacturing the automobile wheel rim but also the manufacturing cost of the automobile wheel including the automobile wheel rim, and it is possible to rapidly mass-produce the automobile wheel due to the reduction of the working time, thereby contributing to productivity improvement.

1 schematically shows a manufacturing process of a vehicle wheel rim according to the prior art.
2 shows a concept of a method for manufacturing a vehicle wheel rim according to a preferred embodiment of the present invention.
3 schematically shows a method of manufacturing a vehicle wheel rim according to a preferred embodiment of the present invention.
4A schematically illustrates a method of forming beads in a vehicle wheel rim according to a preferred embodiment of the present invention.
FIG. 4B is a schematic view illustrating a method of molding a bead in a vehicle wheel rim according to another embodiment of the present invention.
5 is a perspective view of a vehicle wheel rim manufactured by a method for manufacturing a vehicle wheel rim according to a preferred embodiment of the present invention.
Figure 6 shows the stress-strain curves of TWIP 980 steel.
7 is a schematic view of an automotive wheel including a wheel rim according to a preferred embodiment of the present invention.

In order to facilitate an understanding of the description of the embodiments of the present invention, elements denoted by the same reference numerals in the accompanying drawings are the same element, and among the constituent elements that perform the same function in each embodiment, Respectively.

Further, in order to clarify the gist of the present invention, a description of elements and techniques well known in the prior art will be omitted, and the present invention will be described in detail with reference to the accompanying drawings.

It is to be understood, however, that the spirit and scope of the present invention are not limited to the embodiments shown, but may be suggested by those skilled in the art in other forms, additions, or alternatives, .

As shown in FIG. 2, a method of manufacturing a wheel rim according to an embodiment of the present invention includes a preparation step (S100) of preparing a workpiece, a welding step (S100) of forming a cylindrical body by welding an end of the prepared workpiece Forming a bead in the rim by using a roll; and forming a bead in the rim by using a roll (S400).

A feature of the present invention resides in the rim shaping step and the bead shaping step because the bead can be formed in the rim by using a roll even in the bead shaping step as in the rim shaping step using the roll.

3, the material 1 made of a specific material is cut into a plate material 10 having a predetermined shape by a process such as blanking, and a circular tube shape is formed by the plate material 10 And then the end portion is welded to form the joint portion 11.

Then, the initial plate 10 can be machined into the shape of the cylindrical body 12. At this time, in order to compensate for the strength of the welded joint 11 and prevent deformation, a groove process may be added to the edge of the cylindrical body to give a predetermined bending or a proper deformation.

Next, a press forming process using the upper mold 20 and the lower mold 30 or a roll forming process using a plurality of rolls 40a and 40b is performed to expand the diameter of the cylindrical body 12 Or to shape and expand the flange. For example, such a process has a flaring process.

On the other hand, the rim can be molded in a size initially designed. Here, either the press process or the roll forming process may be performed or may be replaced only by the roll forming process according to the judgment of the operator, which can be appropriately changed depending on the operator and the working environment. Further, it goes without saying that an additional dimension correction work can be performed under the judgment of the operator.

When the molding of the wheel rim 13 is completed by the above-described process, a bead molding step may be performed in which the cross-sectional shape of the wheel rim 13 is deformed to reinforce the strength of the wheel rim 13.

As shown in FIG. 4A, along the circumferential surface of the wheel rim 13 formed by the above-described processes, the bead 13a protruding or concaved in the center direction of the wheel rim 13 is machined, The cross-sectional shape of the wheel rim 13 is deformed, thereby reinforcing the strength. It should be noted that the shape and size of the beads 13a are not limited to the present invention and can be appropriately changed by those skilled in the art.

The bead 13a which has conventionally been processed by a conventional hydroforming process can be processed by a plurality of rolls rotated in the present invention. That is, in the bead forming step according to the preferred embodiment of the present invention, a plurality of beads 13a may be formed along the circumferential surface of the wheel rim 13 by applying a stamping structure to each surface of the roll.

That is, the shape of the bead 13a to be machined is formed on the surface of one side roll, and the shape of the bead 13a is formed on the surface of the other side roll at an obtuse angle to rotate the two rolls, The circumferential surface of the wheel rim 13 is placed between the rolls and pressed to stamp the shape of the bead 13a.

Therefore, in the bead forming step according to the preferred embodiment of the present invention, the first rotating roll 51 in which the shape corresponding to the bead 13a is etched in a relief shape on the roll surface, and the bead 13a The second rotating roll 52 may be provided with a stamping roll preparing step of preparing a second rotating roll 52 in which the shape corresponding to the second rotating roll 52 is etched at an angle.

However, a person skilled in the art can apply the shape and size of the surface of a plurality of rolls differently. That is, the shape corresponding to the bead may be etched at an obtuse angle on the surface of the first rotating roll 51, and the shape corresponding to the bead may be relieved at the surface of the second rotating roll 52 by an embossing. A roll surface processing method widely known by conventional techniques including laser etching can be appropriately selected and used.

In addition, a person skilled in the art can change the outer diameter of the roll. That is, the outer diameter of the first rotating roll 51 and the second rotating roll 52 may be the same as the inner diameter of the wheel rim 13 as shown in FIG. 4B. In addition, the outer diameter of the first rotating roll and the second rotating roll can be freely changed within the limit size with the inner diameter of the wheel rim 13 being a limit size.

In such a case, the size of the outer diameter of the first rotating roll and the second rotating roll can be determined by reflecting the conditions such as the characteristics or physical properties of the material to be prepared, the shape, size, and depth of the bead to be processed, It will be obvious to those skilled in the art that the larger the size of the material, the greater the force to press the material.

According to the above-described method, the wheel rim 13 having a plurality of beads 13a as shown in Fig. 5 can be manufactured. In addition, since roll forming is also used for forming the bead 13a, which is a post-process, by using roll forming, which is necessarily used in the process of forming the wheel rim 13, continuity and convenience of the process can be ensured. In addition, due to the fact that the wheel rim 13 and the bead 13a are formed by using the roll, there is little need to replace the peripheral equipment or the apparatus with a large amount, so that the working time can be shortened and the flexibility of the production process can be secured .

In addition, in the method of manufacturing an automobile wheel rim according to a preferred embodiment of the present invention, the material may be provided as TWIP steel. Figure 6 shows the stress-strain curves of TW980 steel, a kind of DP980 steel, TRIP980 steel and TWIP steel.

TWIP980 steel is a high strength and high strength steel which contains iron (Fe), carbon (C), silicon (Si), manganese (Mn), aluminum (Al), sulfur (S) and other impurities. And the structure includes at least one of ferrite, martensite and austenite, whereby the steel has an elongation of 45 to 65%. The TWIP980 steel having such physical properties is a suitable material for the method of manufacturing an automobile wheel rim according to the present invention, but it is not limited to the present invention, and various kinds of steel may be applied according to the judgment of those skilled in the art.

According to another aspect of the present invention, there is provided a wheel rim manufactured by the wheel rim manufacturing method as described above, and the wheel rim including the wheel rim can be manufactured by referring to the wheel rim. 7, the automobile wheel 100 including the wheel rim manufactured by the automobile wheel rim manufacturing method according to the preferred embodiment of the present invention includes the bead 13a manufactured by the automobile wheel rim manufacturing method as described above, And a disc member 60 coupled to the wheel rim.

The disc member 60 may be welded to engage the wheel rim 13, or a bolt 61c may be used as shown in Fig. However, the method for joining the disk member to the wheel rim is not limited to the present invention, and for example, the joining method using the bolt as shown in Fig. 7 will be described.

An auxiliary rim 70 having the same diameter as the wheel rim may be provided for coupling the disc member 60 to the wheel rim 13.

That is, a flange is formed on one side of the wheel rim 13 including the bead 13a, and a plurality of coupling holes 61a are formed in the flange in the circumferential direction. A flange is formed on one side of the auxiliary rim 70 so as to form a plurality of coupling holes 61a corresponding to the coupling holes 61a in the circumferential direction of the flange.

A plurality of disk coupling holes 61b corresponding to the coupling holes 61a provided in the wheel rim 13 and the auxiliary rim 70 are formed in the circumferential direction of the disk member 60, (60) is arranged between the wheel rim (13) and the auxiliary rim (70) so that the coupling hole (61a) and the disk coupling hole (61b) are aligned with each other.

A bolt 61c passing through the coupling hole and the disk coupling hole is inserted and the end thereof is fixed by inserting a nut 61d to join the disk member 60 to the wheel rim 13, .

It should be understood, however, that the methods described are by way of preferred embodiments of the present invention and are not intended to be limited by the present invention.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. It will be apparent to those of ordinary skill in the art.

1: Material 10: Plate
11: joint part 12: cylindrical body
13: Wheel rim 13a: Bead
20: upper mold 30: lower mold
40a, 40b: roll 51: first rotating roll
52: second rotating roll

Claims

A rim forming step of joining the plate members and forming a rim; And
A bead forming step of deforming a cross section of the rim using a roll;
Of the vehicle wheel.

The method according to claim 1,
The bead forming step includes:
Wherein a stamping structure is applied to the surface of the roll to form a bead in the rim.

3. The method of claim 2,
The bead forming step includes:
A first rotating roll having a surface formed in a convex shape corresponding to the beads,
And a second rotating roll having a shape corresponding to the beads formed on the surface thereof at an obtuse angle.

The method according to claim 1,
A flanging step of deforming the size or cross-section of the diameter of the rim;
Further comprising the steps of:

5. The method according to any one of claims 1 to 4,
The bead forming step includes:
Wherein the outer diameter of the roll is prepared to be the same as the inner diameter of the rim.

6. The method of claim 5,
The plate member
Wherein the step of preparing the wheel rim comprises the steps of:

A wheel rim produced by the method for manufacturing an automobile wheel rim as set forth in any one of claims 1 to 4.