JPH03138045A - Method for forming parts having flange - Google Patents

Abstract

PURPOSE:To obtain parts having uniformity in circumference of a flange without under fill in thin part by inclining bottom face of cavity for forming the flange according to thickness of the flange at the time of forming the parts having the circumferential flange by using hydraulic cushion. CONSTITUTION:After closing a raw material 1 between an upper die 2 and a lower die 3, while cushioning the lower die 3, the raw material 1 is pressurized with between upper punch 4 in the upper die 2 and lower punch 5 in the lower die 3. According to thickness of the flange 1b to be formed, the bottom face is inclined and the raw material 1 is allowed to flow in the cavity 2b to form the flange 1b. Further, the raw material 1 is allowed to flow into the cavity 3a for forming a lower hub 1c to form the parts having the flange at outer circumferential part, and the parts without under fill in the thin part of flange is obtd. By this method, by closedly forming the whole circumference of flange without any restraint, the forming method for the parts having flange, which can be formed with a small capacity press, can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of forming a component having a flange around the periphery by hot-switching forging.

[Conventional technology]

Conventionally, a flange 1 has a thick wall portion 1d and a thin wall portion 1e around the periphery.
When molding a mechanical part A as shown in FIGS. 3 and 4 having a shape of 1.b, a large press having a molding capacity of 2000 to 3000 tons is used to perform hot forging in 3 to 4 steps.

[Problem to be solved by the invention]

However, conventional molding methods use large presses and are molded in multiple steps, resulting in products that are not high or low.
There are problems such as low productivity.

Furthermore, when molding is performed using a cushion die, a lack of thickness B as shown in FIG. 5 occurs in the thin wall portion 1e, which is molded without restraint, with respect to the thick wall portion 1d where the outer peripheral portion of the flange is restrained. There were also some problems, such as a high rate of non-defective products.

This invention was made with the aim of improving the above-mentioned problems, and aims to provide a method for forming parts having flanges that does not cause underfilling and can be formed using a press with a small capacity. .

[Means and operations for solving the problem] In order to achieve the above object, the present invention has a method of closing the material between the upper mold and the lower mold, and then lowering the upper mold and the upper punch while cushioning the lower mold. Then, by pressurizing the material between the upper punch and the lower punch in the lower mold, the material flows into a cavity whose bottom surface is inclined according to the thickness of the flange to be formed, and the flange is formed. By allowing the material to flow into the cavity in which the lower hub is molded to mold a part having a flange on the outer periphery, a part with no missing thickness in the thin part of the flange can be obtained.

The present invention also provides a method for molding a part having a flange, which can be molded using a press with a small capacity by performing closed molding without restricting the entire periphery of the flange.

〔Example〕 An embodiment of the method of this invention will be described in detail with reference to the drawings.

First, a cylindrical material 1 is heated to a molding temperature of 800 to 900 DEG C., and then placed between an upper mold 2 and a lower mold 3, and the upper mold 2 and lower mold 3 are closed as shown in FIG.

An upper punch 4 and a lower punch 5 are provided in the upper die 2 and the lower die 3, respectively, and cavities 2a and 2 are formed between the upper punch 4 and the upper die 2 to form the upper hub 1a and the flange 1b.
A cavity 3a for molding the lower hub 1c is provided between the lower punch 5 and the lower mold 3, and a cavity 2b for molding the flange 1b is a portion for molding the thick portion 1d of the flange 1b. and a portion for molding the thin wall portion 1e, and the angle α of the bottom surface of the cavity 2b for molding the thick wall portion 1d is, for example, 5° with respect to the horizontal plane.
The angle β of the bottom surface of the cavity 2b in which the thin portion 1e is formed is set to 1° to 4″, roughly so that α>β.

Next, when the slide (not shown) further descends from the state shown in FIG. Material 1 is placed between the lower punches 5 in the lower mold 3.
is pressurized, and the raw material 1 first flows to the cavity 2a for molding the upper hub 1a and the cavity 3d for molding the lower hub 1c, and then to the cavity 2b for molding the flange 1b.

Since the angle β of the bottom surface of the cavity 2b that molds the thin-walled portion 1e is set in advance to α>β with respect to the angle a of the bottom surface of the cavity 2b that molds the thick-walled portion 1d of the flange 1b, the thin-walled portion 1e is The flow of the raw material 1 into the molding cavity 2b is promoted and the entire circumference becomes uniform, so that insufficient thickness is prevented from occurring in the thin-walled portion 1e. At the same time, the material 1 is also filled in the cavity 3a for forming the lower hub, and when the forming of the material 1 is completed, the upper mold 2 and the upper punch 4 are raised, and the lower mold 3 and the lower punch are 5 is the first
It rises to the position shown in the figure, and then the lower punch 5 pushes out the molded product from the inside of the lower die 3, so that a part A having a flange 1b on the outer periphery as shown in FIGS. 3 and 4 is obtained. .

〔Effect of the invention〕

As described in detail above, when molding a part having a flange around it using a hydraulic cushion, the bottom surface of the cavity in which the flange is molded is sloped according to the wall thickness of the flange, thereby making the part thinner. Since the flow of material to the flange part is promoted, parts with uniform flange circumference and no missing parts in thin parts can be obtained, and the outer periphery of the flange can be molded without restraint. This allows molding to be performed using a press with a small capacity, which allows parts to be provided at low cost.

[Brief explanation of the drawing]

1 and 2 are molding process diagrams showing one embodiment of the present invention, FIG. 3 is a plan view of the molded part, FIG. 4 is a sectional view taken along line IV-IV in FIG. 3, and FIG. The figure is an explanatory diagram of a part molded by a conventional molding method. 1 is the material, 1b is the flange, 1c is the lower hub, 1d is the thick part, 1e is the thin part, 2 is the upper mold, 2a is the cavity, 3 is the lower mold, 3a is the cavity, 4 is the upper punch, 5 is the lower part Punch, A is the part.

Claims (2)

[Claims] (1) After closing the material 1 between the upper mold 2 and the lower mold 3, lower the upper mold 2 and the upper punch 4 while cushioning the lower mold 3, and lower the upper punch 4 and the lower part of the lower mold 3. By pressurizing the material 1 between the punches 5, the material 1 flows into the cavity 2b whose bottom surface is inclined according to the thickness of the flange 1b to be formed, forming the flange 1b, and forming the lower hub 1c.
Flow the material 1 into the cavity 3a that molds the part A.
A method for forming a part having a flange, the method comprising: forming a part having a flange. (2) A claim in which the angle β of the bottom surface of the cavity 2b that molds the thin wall portion 1e is set in the relationship α>β with respect to the angle α of the bottom surface of the cavity 2b that molds the thick wall portion 1d of the flange 1b. 1. The molding method described in 1.