JPS61232029A - Metal die device for closed incremental forging - Google Patents

Abstract

PURPOSE:To increase the quality of a large-sized closed forging product by forming the relief part of the specified shape at the specified position on the forming face of the upper die of the metal die device for prestage and post stage and by forming the boundary of the relief part and forming face in circular arc shape as well. CONSTITUTION:The relief part 5 in opposition to the part where the underfill of a forming product is apt to be caused is provided on the upper die 4a for the first stage. On the other hand the forming surface 6 is provided over the larger area than the part equivalent to the relief part 5a of the upper die 4a for the first stage on the upper die 4b for the second stage and a relief part 7 is provided on the other part. The boundary part of the relief parts 5, 7 of this both upper dies 4a, 4b and the forming surface is continued with smooth circular arcs. By forging with metal dies like this the materials gathered to the relief part with being in excess in the forming part are filled up smoothly on the forming surface in the second stage and a good closed forging product can be obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a punch for closed incremental forging.

Conventional technologyForged products with complex shapes, such as track links, require multiple processes in normal die forging, such as pasta, blocker,
The material must go through a process such as a finisher to make it into a product, and then the mold must be filled with the material by producing a large number of holes to perform the forging process. For this reason, the normal forging method is not preferable in terms of resource and energy conservation.

Therefore, closed forging that does not emit paris can be considered, but at the moment it is 0.1 to 2 K? It is only applied to small parts with relatively simple shapes.

Problems to be Solved by the Invention When the conventional closed forging method is used to mold large parts with complex shapes such as track links, the mold is filled with material, making it difficult to produce a satisfactory molded product. If you try to achieve this, the forming load will be large and a very large press will be required.

Means and Effects for Solving the Problems The present invention was conceived in view of the above-mentioned problems, and includes a molding surface of a mold device for a pre-processing process, which is provided with a relief portion facing a portion where underfilling of the molded product is likely to occur. Further, on the molding surface of the mold device for the post-process, a molding surface is provided over an area larger than the portion corresponding to the relief portion of the molding surface of the mold device for the pre-process, and relief portions are provided in other parts. In addition, the boundary between the relief part of each mold device and the molding surface has a smooth arc shape, so that the material is transferred to areas where underfilling of the molded product is likely to occur in the pre-process, and The parts where underfilling is likely to occur are molded, and the material is moved in each step.

Example Embodiments of the present invention will be described based on the drawings.

In the figure, 1 is a mold device for the first process, and 2 is a mold device for the second process.
b, and upper molds 4a and 4b. Both mold equipment 1
, 2 lower mold 3a.

The mold 3b has a hole shape, and the mold is engraved on the bottom of the hole. Further, the upper molds 4a and 4b of both mold apparatuses 1 and 2 are the lower mold 3a.

It has a punch shape that fits tightly into the hole-shaped portion 3b, and a mold as an upper mold is carved at the tip of the punch.

In the upper molds 4a and 4bVc of both the mold apparatuses 1 and 2, the upper mold 4a for the first step is provided with a relief portion 5 facing a portion where underfilling of the molded product is likely to occur. On the other hand, the upper mold 4b for the second step has a relief part 5 in the upper mold 4a for the first step.
The molded product 6 is provided over an area larger than the area corresponding to the part, and relief parts 7 are provided in other parts. The boundary between the relief part 5.7 of the rain top m4a, 4b and the molding surface is continuous with a smooth circular arc. Note that the relief section refers to a space created by cutting out the forming surface of the punch in the closed forging method.

In the above configuration, in the mold apparatus 1 for the first step, when molding is performed using the lower mold 3a and the upper mold 4a, the material left over at the molding section formed by both molds 3a and 4a is moved to the relief section 5. .

Next, in the mold device 2 for the second step, the portion released in the first step is molded by the molding surfaces 6 of the lower mold 3b and the upper mold 4b, and the material of this portion is filled and molded. The material left over at this time is moved to the relief part 7 of this upper mold 4b,
The amount is small. Note that by shaping the molding surface of the mold device 1 for the first step in a shape that takes into account the amount of relief in the second step, the amount of relief in the second step can be absorbed.

If necessary after this second molding step, molding is performed in a plurality of subsequent molding steps using an upper mold provided with a similar relief part, and a sizing step is included in the final step.

Effects of the Invention According to the present invention, large parts with complex shapes such as track links can be hermetically forged with a smaller forming load than normal hermetic forging, and without any underfilling. In addition, when the part that became the relief part in the previous process is molded in the later process, the material moves smoothly, and the fluidity is particularly good at the boundary between the relief part and the non-relief part. It is possible to prevent the occurrence of cracks.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a perspective view of a mold device for the first step, FIG. 2 is a perspective view of a mold device for the second step, and FIG. 3 is a perspective view of a mold device for the second step. 8 is a sectional view taken along the line I-III in the figure, and FIG. 4 is a sectional view taken along the line ■-■ in FIG. 1.2 is a mold device, 3a and 3b are lower molds, and 4a. , 4b is an upper mold, 5 and 7 are relief parts, and 6 is a molding surface.

Claims (1)

[Claims] Lower molds 3a and 3b in which a mold is carved on the bottom of the hole-shaped part;
In the mold apparatuses 1 and 2 for multiple processes, which are made up of upper molds 4a and 4b that fit tightly into the hole-shaped portions of the lower molds 3a and 3b and have molding molds engraved on their tip surfaces, A relief part 5 is provided on the molding surface of the mold device 1 to face a portion where underfilling of the molded product is likely to occur, and a relief portion 5 is provided on the molding surface of the mold device 2 for the post-process, and the mold device 1 for the pre-process is provided on the molding surface of the mold device 2 for the post-process. A molding surface 6 is provided over a larger area than the portion corresponding to the relief portion 5 of the molding surface, relief portions 7 are provided in other portions, and each mold device 1, 2 is provided with a relief portion 7.
A mold device for closed incremental forging, characterized in that the boundary between the relief parts 5 and 7 and the forming surface is shaped into a smooth arc.