JP2000225432A - Production of disk for automobile wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an economically excellent production method for a disk for an automobile wheel by using a good precision and simple die as compared to a conventional one. SOLUTION: In a production method of a disk for automobile wheel consisting of a hub mounting part 12, a inner side inclined part 14, a hat part 15, a decoration part 16 and a rising part 18, forming plural decorative holes 17 to the peripheral direction of the decoration part 16, forming of a decorative hole 17, after drawing forming of the inner side inclined part 14 and the hat part 15, is conducted at a state of a flat face before drawing forming of the decoration part 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a disk for an automobile wheel, particularly a disk frequently used for a passenger car.

[0002]

2. Description of the Related Art As shown in FIG. 4, an automobile wheel disc 1 used for a passenger car has a hub hole 2 at a center portion, a hub mounting portion 3 radially outward of the hub hole, and a hub mounting portion 3. Are usually 4 to 6 bolt holes 4 in the circumferential direction.
Is provided. And it continues to the hub mounting part 3,
An inner inclined portion 5 which rises toward the outside in the radial direction, and a hat portion 6 which is connected to the inner inclined portion 5 and corresponds to the top of the mountain is formed. Further, the design part 7 which is gently inclined outward from the hat part 6 in the radial direction.
Is formed, and in the circumferential direction of the design portion 7, the design
For the purpose of cooling inside the disc 1 and reducing the weight,
Alternatively, a plurality of oval decorative holes 8 are formed. A rising portion 9 is connected to the design portion 7, and the rising portion 9 rises inward in the axial direction of the disk 1 in parallel with the axial direction of the disk 1. This is the basic structure of a general disk often used for passenger car wheels. Shape. Conventionally, in order to form a disk having this shape, the disk is formed through a process shown in FIG. First, a plate-shaped blank 1 ′ shown in step (1) of FIG. 5 is prepared. Next, the basic sectional shape of the disk shown in the step (7) is completed through the drawing forming step, the outer peripheral cutting, and the center drilling step of 4 to 6 steps. To several (4-1
(About 5 holes).

[0003]

However, this decorative hole 8
In order to prevent the formation of burrs in the decoration hole 8 and the sharpness of the periphery of the decoration hole 8 to cause a problem in safety measures, the design portion 7 of the disc 1 As shown in FIG. 6, the punch 113 and the die 111 need to be inclined at a certain angle with respect to the axial direction of the decorative hole punching die, and the punch 113 and the die 111 need to be assembled into the die 112. In order for the movement of the 113 to be inclined with respect to the axial direction, it is necessary to provide the upper mold 115 with the cam 114. For this reason, precision is required in the production of the decorative hole mold, which increases the cost of the mold. In addition, since the vertical movement is converted into an inclined movement, the movement is not easy, and the punch 113 and the die 111 The punch 113 and the die 111 were easily damaged by the interference. SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a wheel disk for an automobile, which can eliminate punch and die breakage accidents and greatly reduce mold manufacturing costs by simplifying a decorative hole punching die when forming decorative holes. The purpose is to provide.

[0004]

The present invention to achieve the above object is as follows. (1) In a method of manufacturing a disc for an automobile wheel, comprising a hub mounting portion, an inner inclined portion, a hat portion, a design portion, and a rising portion, and having a plurality of decorative holes in the design portion in a circumferential direction, the decorative hole is formed. After the drawing process of the inner inclined portion and the hat portion, before the drawing process of the design portion, the portion to be the design portion after the drawing process has a flat surface parallel to a plane orthogonal to the axial direction of the disk. A method of manufacturing a disc for a vehicle wheel, wherein the method is performed when the disc is in a state. (2) The method of manufacturing a disc for an automobile wheel according to (1), wherein after forming the decorative hole, an inclined wall which rises from the front side in the axial direction of the disk toward the inside in the axial direction is formed around the decorative hole. . (3) The method of manufacturing a disc for an automobile wheel according to (1), wherein after the decorative hole is formed, an inclined wall which rises from the inside in the axial direction toward the front side in the axial direction is formed around the decorative hole. . (4) The method for manufacturing a disc for an automobile wheel according to (1), wherein after the decorative hole is formed, a chamfered portion is formed by performing a chamfering process around the decorative hole on the inner side in the axial direction of the disk.

In the method of manufacturing a disc for an automobile wheel according to the above (1), the decorative hole is formed after the drawing process of the inner inclined portion and the hat portion, before the drawing process of the design portion, and after the drawing process. This is performed when the part to be formed is on a flat surface parallel to a plane perpendicular to the axial direction of the disk, so the mold can be simplified and the movement of the punch with respect to the die in the same direction as the vertical movement of the press Because it ’s easy,
The mold is easy to manufacture and the punch and die are less damaged. In the above methods (2) to (4), after the decorative hole is formed, a sloped wall and a chamfered portion are formed by chamfering around the decorative hole. In addition, deformation and cracking of the decorative hole can be prevented.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for manufacturing an automobile disk according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 shows steps of a method for manufacturing a vehicle wheel disc according to the present invention. First, as shown in (1), a blank material 10 'for a disk is prepared. Next, in the step (2), after the basic shape of the disc is completed, a portion radially inward of the hat portion 15 is narrowed down. Next, in step (3), the hat portion 15 and the inner inclined portion 14 radially inward of the hat portion 15 are formed.
Of the flat hub mounting portion 12 where a bolt hole is to be formed later, by reverse drawing. At this time, after drawing, the design part 16 and the rising part 1
The portion to be 8 is left flat. Reference numeral 16a denotes a design part in a planar state. Further, at the time of completion, a plurality of portions 13 in which the bolt holes are formed may be formed in the circumferential direction by pressing.

Next, in step (4), the flat design portion 16 is formed.
A plurality of decorative holes 17 are punched out in the circumferential direction of the disk. The decorative holes 17 are formed when the flat design portion 16a has a flat surface parallel to a plane perpendicular to the axial direction of the disk 10. Therefore, the decorative holes 17 are formed as shown in FIG.
Can be performed with the mold shown in FIG. The formation of the decorative hole 17 in the process of FIG.
9 and the die 20 are parallel, and the mold 22 can be manufactured simply. Further, unlike the conventional case, the die is complicated by tilting the punch and the die, and the damage to the punch 19 and the die 20 due to poor accuracy and the like are small. As a result, the die production cost can be greatly reduced.

Next, in the step (5), the design portion 16a from which the decorative hole 17 has been pressed is drawn and formed into a curved design portion 16. In this state, the rising portion 18 remains flat. Reference numeral 18a indicates a rising portion in a flat stage. Next, in the step (6), the hub hole 11 is punched out. Then, trimming of the disk outer peripheral portion 18a is performed as necessary. In the next step (7), the rising portion 18 is drawn and the flat outer periphery 18a is raised inward in the axial direction of the disk 10 to be in a state parallel to the axial direction of the disk 10. Also, the periphery of the hub hole 11 is
0, and is raised in the axially outward direction to form a hub bore cylindrical portion 11a. Thus, the forming of the basic shape of the disk 10 is completed.

After the decorative hole 17 is formed and before the drawing process of the design portion 16, the peripheral portion of the formed decorative hole 17 is
As shown in (1), an inclined wall 17a that rises from the front side in the axial direction of the disk 10 toward the inner side (back side) in the axial direction is formed. It is desirable to form the inclined wall 17b from the inside toward the front side or, as shown in (3), to form a chamfered portion 17c by performing chamfering around the decorative hole on the inner side in the axial direction of the disk. Inclined wall 17a, 1
In the case of the formation of 7b, the rigidity and strength of the peripheral portion of the decorative hole 17 are increased, and in the case of the formation of the chamfered portion 17c, the cutout effect of the peripheral portion of the decorative hole 17 is reduced. As a result, when the design portion 16 is drawn after the decoration hole 17 is formed, it is possible to prevent the decoration hole 17 from being deformed due to the forming, and to prevent a crack from being generated around the decoration hole 17.

[0010]

According to the method for manufacturing a vehicle wheel disc of the first aspect, the decorative hole is formed in the design portion after the drawing process of the inner inclined portion radially inside the hat portion and the hat portion. Before the drawing process, since the part to be the design part after the drawing is a flat surface parallel to the plane perpendicular to the axial direction of the disc, it can be performed, so the mold for punching decorative holes can be simplified and the punch Of the die in the same direction as the vertical movement of the press, it is easy to manufacture the die, the punch and the die are less damaged, and the die manufacturing cost can be greatly reduced. Claim 2
According to the fourth aspect, after forming the decorative hole, the peripheral portion of the decorative hole is subjected to an inclined wall or chamfering process. And the occurrence of cracks from the decorative holes can be suppressed.

[Brief description of the drawings]

FIG. 1 is a manufacturing process diagram of a vehicle wheel disc of the present invention.

FIG. 2 is a partial cross-sectional view showing a state in which peripheral processing of a decorative hole is performed.

FIG. 3 is a cross-sectional view illustrating a forming process of a decorative hole according to the present invention.

FIG. 4 is a sectional view showing a basic shape of a disc for an automobile wheel according to the present invention and a conventional one.

FIG. 5 is a process diagram showing a manufacturing process of a conventional automobile wheel disc.

FIG. 6 is a cross-sectional view showing a state in which a decorative hole of a conventional automobile wheel disc is formed and a mold structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Disc 12 Hub mounting part 14 Inside inclined part 15 Hat part 16 Design part 17 Decorative hole 18 Rise part 17a, 17b Inclined wall 17c Chamfer part

Claims (4)

[Claims] A hub mounting portion, an inner inclined portion, a hat portion,
In a method of manufacturing a disc for an automobile wheel, comprising a design portion and a rising portion, the design portion having a plurality of decorative holes in a circumferential direction, the forming of the decorative hole is performed by a drawing process of the inner inclined portion and the hat portion. Later, before the drawing process of the design portion, the process is performed when the portion to be the design portion after the drawing process is in a flat surface parallel to a plane orthogonal to the axial direction of the disk, for an automotive wheel. Disc manufacturing method. 2. An automobile wheel disc according to claim 1, wherein after the ornament hole is formed, an inclined wall which rises from the front side in the axial direction of the disc toward the inside in the axial direction is formed around the ornament hole. Production method. 3. An automobile wheel disc according to claim 1, wherein an inclined wall which rises from the inside in the axial direction of the disc toward the front side in the axial direction is formed around the ornament hole after the formation of the ornament hole. Production method. 4. The method of manufacturing a disk for an automobile wheel according to claim 1, wherein after the decorative hole is formed, a chamfered portion is formed by performing a chamfering process around the decorative hole on the inner side in the axial direction of the disk.