JPH0671639B2 - Method for manufacturing aluminum wheel material - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for manufacturing a tube type aluminum wheel material.

2. Description of the Related Art Conventionally, a tube-type aluminum wheel material has been produced by press-forging a rough ground to produce a rough-shaped intermediate molded product, and processing this intermediate molded product by a spinning machine to finish the shape before heat treatment.

In the conventional method of press forging and spinning, it is necessary to form a sufficient taper on the inner diameter surface of the intermediate product by forging to prevent the material from sticking to the upper die during press forging. Since the product has many uneven thicknesses, it is necessary to consider the machining allowance in advance in anticipation of occurrence of this uneven thickness. Further, it is impossible to perform a series of press forging by heating once to finish the product into a shape before heat treatment, and it is necessary to finish by spinning.

Problems to be Solved by the Invention As described above, the conventional method of press forging and spinning is not suitable for mass production at low cost because it has many processing steps and the material yield is low due to uneven thickness. It was

The present invention eliminates such drawbacks and proposes a method for producing an aluminum wheel that can be molded into a shape before heat treatment by one step in one step.

Means for Solving the Problems The present invention comprises a lower mold which rotates in a horizontal plane around a vertical rotation axis and an upper mold which rotates around a rotation axis fixed at an angle α with respect to the rotation axis. A manufacturing method in which a heated aluminum block is pressed by a rotary forging machine in which an upper die is vertically movable and is pressed and forged while rotating an object to be forged to form an aluminum wheel material having a shape before heat treatment.

This invention puts a heated aluminum block in the lower die of the rotary forging machine, and rotates the upper die at the same time by the rotary axis inclined by the angle α with respect to the vertical axis and the lower die by the vertical rotary axis. At the same time, since the upper mold is lowered and the aluminum block is pressed, the contact surface with the aluminum block of the upper mold is small, and the molding can be performed without the inner diameter taper (see FIGS. 1 (b) and (c)). Further, the aluminum block is pressed by pressing the upper mold, but since the backward extrusion capability at this time is large, it is possible to finish the block from the block to the shape before heat treatment in one step by heating once.

Embodiment An embodiment of the present invention will be described with reference to FIG.

In order to carry out the present invention, a lower die that rotates in a horizontal plane about a vertical rotation axis A and a rotation axis B that is fixed at an angle α with respect to the rotation axis A are rotated, and can be raised and lowered. A rotary forging machine consisting of the configured upper mold is used.

FIG. 1 (a) is an explanatory view showing a state at the time of starting the processing of the rotary forging machine. First, the upper die (2) is raised before starting the processing (the drawing is omitted) and the temperature is about 450 ° C. The aluminum block (4) heated to the above is charged into the hole mold of the lower mold (1). Then, as shown in FIG. 1 (a), the lower mold (1) is attached to the rotation axis A.
At the same time, the upper die (2) is rotated at an angle α with respect to the rotation axis B while being rotated in a horizontal plane, and is lowered while being rotated to start plastic working. The rotation speed of the rotating shaft A and the rotating shaft B is about 90 rpm.

Then, when the upper die (2) is gradually lowered to pressurize the material, as shown in FIG. 1 (b), the material is plastically deformed and the space between the upper die (2) and the lower die (1). The material is extruded rearward into the formed space.

Further, when the upper die (2) is lowered and lowered until the guide portions (5) of the upper die (2) and the lower die (1) come into contact with each other,
As shown in FIG. 1 (c), the material is filled in the space formed between the upper die (2) and the lower die (1) to become a processing material having a desired shape, and the processing is completed.

In this way, a forged product having a shape before heat treatment of an aluminum wheel, that is, an aluminum wheel material (6) shown in FIG. 2 was manufactured. This aluminum wheel material (6) is
With the processing equipment such as lathe and turning in the subsequent process, the second
The aluminum wheel (9) of the product was finished by removing the machining allowance (8) indicated by the diagonal lines in the figure.

For comparison, a conventional method was used to press-forge an aluminum block heated to about 500 ° C using a 9000T hydraulic press to manufacture the aluminum wheel material (7) shown by the broken line in Fig. 2 and use this forged product. Spinning processing was applied to finish the shape of the aluminum wheel before heat treatment. Then, the aluminum wheel was finished by removing the processing in the same post process as above.

The cross-sectional shapes of the aluminum wheel material (6) according to the embodiment of the present invention and the aluminum wheel material (7) according to the conventional method, which are made by the above-mentioned embodiment, are overlapped for comparison and are shown in FIG.
The former is shown by a solid line and the latter is shown by a broken line. The shaded portion in the drawing is a machining allowance (8) to be machined and removed in a later step in the case of the present invention, and the inside thereof is a product aluminum wheel (9).
Becomes

As described above, according to the embodiment of the present invention, the machining allowance is small because the machining allowance (8) is removed from the aluminum wheel material (6) to finish the product aluminum wheel (9).

On the other hand, in the case of the conventional method, the machining cost is large because the aluminum wheel material (7) is removed to the inner surface of the machining cost (8) to finish the product aluminum wheel (9). Therefore, according to the present invention, it is understood that the machining allowance is remarkably reduced over the entire surface and the material yield is improved.

EFFECTS OF THE INVENTION In the present invention, since the upper die is processed by using the rotary forging machine that rotates while tilting with respect to the lower die, the inner surface of the forged product is in partial contact with the upper die, and therefore the inner surface of the forged product is There is no need to provide a taper. Also, in the forging at that time, the material is pressed by the upper mold and the space formed between the upper mold and the lower mold is processed in the state of being extruded backward, and since the deformability is large, the aluminum wheel material is manufactured in one process. It can be finished in the shape of. Moreover, since there are no defects such as uneven thickness, the machining allowance that is eliminated by machining in the subsequent process can be made sufficiently small and the material yield can be improved.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a state of being forged by a rotary forging machine according to an embodiment of the present invention. FIG. 1 (a) is at the start of processing, FIG. 2 (b) is during processing, and FIG. 1 (c) is at the end of processing. It is in a state. FIG. 2 is a sectional view of a product aluminum wheel material. 1 ... Lower mold, 2 ... Upper mold, 3 ... Forged product (aluminum wheel material), 4 ... Aluminum block, 5 ... Guide part, 6
…… Invention method aluminum wheel material, 7 …… Conventional method aluminum wheel material, 8 …… Machining allowance, 9 …… Product aluminum wheel, A …… Vertical rotation axis, B …… Inclined rotation axis.

Claims (1)

[Claims] 1. A lower die that rotates in a horizontal plane about a vertical rotation axis, and an upper die that rotates about a rotation axis fixed at an angle α with respect to the rotation axis and that can move up and down. A method for manufacturing an aluminum wheel material, characterized in that a heated aluminum block is pressed by a rotary forging machine that presses and forges a forged product while rotating it to shape it into a shape before heat treatment.