JP2520726B2 - Method for forming a component having a flange - Google Patents

Description

TECHNICAL FIELD The present invention relates to a molding method capable of molding a component having a flange in one step.

[Conventional technology]

Conventionally, when a mechanical part b having a flange a as shown in FIG. 6 (e) is formed by hot forging, first, a raw material c shown in FIG. 6 (a) is heated, and then FIG. 6 (b),
As shown in (c) and (d), they are sequentially molded and finally burr d
Are cut off to finish the parts shown in FIG.

[Problems to be Solved by the Invention]

Even the above-mentioned conventional molding requires at least four molding steps, which requires a large number of man-hours for molding, resulting in poor productivity, and molding such that burrs d are produced, resulting in poor material yield. was there.

Further, since the raw material c is heated to a hot region of 1150 to 1250 ° C. and molded, the dimensional accuracy after molding is poor, so that there is a problem that a large machining allowance must be provided in advance.

The present invention has been made for the purpose of improving the above problems, and an object of the present invention is to provide a method of forming a component having a flange that allows a pre-formed material to be formed into a product in one step.

[Means and Actions for Solving the Problems]

In order to achieve the above object, the present invention heats a preformed material in advance, then first upsets a thin flange portion in a cavity formed between an upper die and a lower die, and thereafter, When the punches provided in the die and the lower die are thrust into the cavity and the boss portion is formed by these punches, a part of the material of the boss portion is caused to flow to the flange portion, and the lacked portion generated in the flange portion Since the wall thickness is thin, even if the flange part is thinned during molding, part of the material of the boss part is made to flow to the flange part when molding the boss part to fill the lacking part. Therefore, it becomes possible to form a part having a flange of good quality with no wall thickness in one step.

〔Example〕

An embodiment of the present invention will be described in detail with reference to the drawings shown in FIGS.

In the figure, 1 is a pre-formed material, and a spherical portion 1b having a diameter larger than this is formed on one end side of the shaft portion 1a, and a small diameter portion 1c sufficiently smaller than the shaft portion 1a is formed on the other end side. There is.

After heating the material 1 to 800 to 900 ° C by a heating furnace, the spherical portion 1b is placed in the cavity 2a of the lower mold 2 as shown in Fig. 2.
Are housed so as to be located above the punch 2b.

Next, in this state, the upper die 3 is lowered as shown in FIG. 3, and first, the shaft portion 1a of the raw material 1 is hydraulically pressurized between the upper die 3 and the lower die 2 so that the flange portion of the component 4 is pressed. Upset molding of 4a.

After that, the punches 2b and 3b provided in the lower die 2 and the upper die 3 are moved up and down, and the spherical portion 1 of the material 1 is moved by these punches 2b and 3b.
A cavity for pressurizing b to form the boss portion 4b of the component 4 and at the same time to form a flange portion 4a of a part of the material 1.
It is made to flow to the 2a and 3a sides to fill the lacking portion 5 generated during flange forming as shown in FIG.

As a result, the component 4 as shown in FIG. 5 in which the flange portion 4a has no deficiency can be obtained in one step.

〔The invention's effect〕

As described in detail above, after heating the preformed material in advance, the thin flange portion is first upset in the cavity formed between the upper mold and the lower mold that are in close contact with each other. Then, when forming the boss portion with the punches provided in the upper die and the lower die, the material of the boss portion is made to flow to the flange portion so as to fill the lacking portion generated at the time of forming the flange portion. As a result, it becomes possible to mold a part having no deficiency in the flange portion in one step, and the productivity can be significantly improved as compared with the conventional method of molding in four steps.

In addition, since burr demolding is not necessary to prevent wall thinning, burrs do not impair the yield, and since it is not necessary to heat up to the hot zone, dimensional accuracy also deteriorates as in the past. There is no.

As a result, a large machining allowance is not required in advance and machining after the forming work is not required, so that the number of steps can be significantly reduced.

[Brief description of drawings]

The drawings show one embodiment of the present invention, FIG. 1 is a plan view of a preformed component, FIGS. 2 to 4 are explanatory views showing a molding process, and FIG. 5 is a plan view of the obtained component. , (A) to (e) of FIG. 6 are conventional explanatory views. 1 is a material, 2 is a lower die, 2b is a punch, 3 is an upper die, 3b is a punch, 4 is a component, 4a is a flange portion, 4b is a boss portion, and 5 is a hollow portion.

Claims (2)

(57) [Claims] 1. A preformed raw material 1 is heated, and then a thin flange portion 4a is first upset in the cavities 3a, 2a formed between the upper die 3 and the lower die 2, and thereafter, When the punches 3b, 2b provided on the upper die 3 and the lower die 2 are thrust into the cavities 3a, 2a and the boss portion 4b is formed by these punches 3a, 2a, a part of the material of the boss portion 4b is used as the flange. A method of molding a component having a flange, characterized in that the part 4a is made to flow to fill the lacking part 5 generated in the flange part 4a. 2. The molding method according to claim 1, wherein the heating temperature of the material 1 is 800 to 900 ° C.