JPS5915733B2 - Method of manufacturing alloy wheels for vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an alloy wheel for a vehicle, and more specifically, a method for manufacturing an alloy wheel for a vehicle in which a rim portion and a disk portion are integrally formed with high precision and at low cost. The present invention relates to a new manufacturing method for efficient manufacturing at a low cost.

2. Description of the Related Art In recent years, alloy wheels such as aluminum wheels have become widely used as wheels for vehicles due to their light weight, durability, and aesthetic appearance when installed. This type of alloy wheel is manufactured by manufacturing the rim part and the disc part separately, and then joining them together by means such as bolting or welding.
Piece and three-piece types are known, but they have drawbacks such as increased manufacturing steps and problems with strength due to welding defects. Therefore, as a solution to the above-mentioned difficulties,
An alloy wheel in which a rim part and a disc part 5 are integrally formed from a disc-shaped forged material has been commercialized. The conventional method for forming this type of one-piece alloy wheel is to forge the outer periphery of a highly malleable, e.g., aluminum alloy disk-shaped material into an annular overhang having a rectangular cross section, and then roll the outer edge to form an annular overhang. 10, and the resulting annular crack is spun using a forming roller (Japanese Patent Publication No. 15209/1983). However, as mentioned above, in the conventional method, the outer edge of the forged material is made into a thick rectangular cross section and this is torn with a roller.
The left and right rims formed on the disk are not symmetrical in shape and have the disadvantage that one rim portion is larger than the other rim portion. In other words, the outer edge of the material is split at the center of the plate thickness, but the volume of the material is determined according to the larger volume of the left and right rim parts, so the split part with the smaller rim volume is cut. It was necessary to remove the excess portion by machining, and therefore a cutting process using a lathe had to be interposed between the tearing and spinning processes. 2
5. Therefore, as a result of repeated studies in order to solve the above-mentioned drawbacks inherent in the manufacturing method of alloy wheels according to the prior art, the inventors carried out the steps listed below in sequence.
It has been found that alloy wheels with excellent precision can be easily obtained.

30 That is, (1) A disk-shaped thick plate material is formed from an alloy material with high malleability.

(2) This disc-shaped material is mounted on a spinning machine, and the outer periphery is subjected to spinning processing 35 using a squeezing roller to offset the periphery.

(3) The outer peripheral edge of the material offset in a dish shape by this ironing is pressed in the radial direction by a tearing roller to tear the material at the center of its thickness.

(4) Subsequently, the split portion is subjected to a spinning process using a compaction roller to form a vehicle wheel in which the rim portion and the disk portion are integrally formed.

Therefore, the main object of the present invention is to provide a method for easily manufacturing an alloy wheel for a vehicle in which a rim portion and a disk portion are integrally formed, with good processing accuracy and with a small number of steps. It is in.

In order to achieve the above-mentioned object, the present invention provides a process in which a disk-shaped material made of a highly malleable alloy is attached to a first mandrel fixed to the main shaft of a spinning machine, and the outer peripheral edge of the disk-shaped material is pressed and spun. The material is offset to have a dish-shaped cross section, and then this dish-shaped material is held between a first mandrel and a second mandrel, and the outer peripheral edge is pressed in the radial direction by a tearing roller to tear the material at the center of its thickness. To provide a method for manufacturing an alloy wheel for a vehicle in which a rim part and a disc part are integrally formed, characterized in that the split part is rolled open and the split part is rolled by a spinning roller to form a desired rim shape. .

Next, the manufacturing method according to the present invention will be described in detail below with reference to preferred embodiments and the accompanying drawings. When carrying out the method according to the present invention, a wheel material 10 formed into a disk shape from a thick plate of a highly malleable alloy, for example, an aluminum alloy, was fixed to the main shaft of a spinning machine as shown in FIG. The wheel material 10 is clamped by a mandrel 12 and a tailstock 14, and the outer peripheral edge of the wheel material 10 is subjected to a so-called ironing spinning process using an ironing roller 16.
It is formed into a dish-shaped cross section as shown in the figure.

At this time, it is assumed that the mandrel 12 has an outer contour corresponding to the shape of one inner surface of the alloy wheel formed by the method according to the present invention at the time of final finishing.
In addition, this iron spinning process uses wheel material 10
The left and right annular rim portions are offset in one direction to the extent that the areas occupied in the space of the left and right annular rim portions are approximately equal. The material 10, which is formed into a dish-shaped profile in cross section as shown in FIG. 2 by the ironing and spinning process, corresponds to the shape of the other inner surface of the alloy wheel formed by the method according to the present invention at the time of final finishing. Another mandrel 18 with an external contour
and the other mandrel 12,
Rim forming processing is performed.

That is, in the state shown in FIG.
is pressed in the radial direction against the outer peripheral edge of the material 10 to tear the material 10 at the center of its thickness, forming an annular tear.
At this time, as described above, the wheel material 10 is offset in the spinning stage so that the volumes of the left and right rims at the time of finishing are equal, so the volumes of the left and right sides of the split portion are approximately equal. Next, as shown by solid lines in FIG. 3, the left and right split portions 24,
26 is performed, and each split portion is stretched so as to conform to the external contours of the mandrels 12 and 18 to form left and right rim portions of a desired shape.

In this final step, an alloy wheel for a vehicle in which the rim portion and the disk portion are integrally formed is easily manufactured with extremely high precision. Moreover, in the method according to the present invention, the disc-shaped material is offset in advance so that the volumes of the left and right rim parts are equal when finished, and then the rim parts are formed by tearing and rolling compression spinning. Although there is an extra correction cutting process in the middle, there is an advantage that no loss occurs due to cutting.

In addition, in the method of the present invention, each process of ironing and spinning of the disc-shaped material, tearing of the outer peripheral edge, and subsequent compaction spinning of the rim part can be performed continuously and consistently, so the time required for processing setup is reduced. Shortening and high efficiency can be achieved. The method for manufacturing an alloy wheel for a vehicle according to the present invention has been described above with reference to preferred embodiments, but the method of the present invention is not limited to these embodiments, and can be modified in many ways within the spirit of the invention. Improvements and changes can be made.

[Brief explanation of the drawing]

1 to 3 are schematic diagrams showing each manufacturing process for carrying out the method for manufacturing an alloy wheel for a vehicle according to the present invention. DESCRIPTION OF SYMBOLS 10... Material, 12... Mandrel, 14... Tailstock, 16... Straightening roller, 18... Mandrel, 20... Tearing roller, 22... Rolling roller, 24
, 26... dehiscence part (rim part).

Claims (1)

[Claims] 1. A disk-shaped material made of a highly malleable alloy is attached to the first mandrel fixed to the main shaft of a spinning machine, and the outer peripheral edge of the disk-shaped material is ironed and spun to offset it into a dish-shaped cross section. The first material is shaped like a plate.
It is held between a mandrel and a second mandrel, and the outer periphery is pressed in the radial direction by a tearing roller to tear it at the center of the thickness of the material, and this split portion is rolled by a spinning roller to form the desired rim shape. A method for manufacturing an alloy wheel for a vehicle in which a rim part and a disc part are integrally formed.