JPH10272532A - Female die for forging - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the development of strain in a formed product and crack on a female die body by releasing the air enclosed in the female die body to outside of the die, at the time of press-forming a material. SOLUTION: A female die is provided with the female die body 3 having forming surface 3A for regulating the outer shape of the formed product 1 and a holding ring 2 for holding the female die body 3. The female die body 3 is divided into plural divided bodies 3a, 3b, 3c. Fine gaps mutually communicated with between the divided surfaces 4, 5 of the divided bodies 3a, 3b, 3c and between a fitting surface 8 between the female die body 3 and the holding ring 2, are formed. The air enclosed in the female die body 3 at the time of press-forming the material 1a is released to outside of the die through the gaps.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a female die for forging.

[0002]

2. Description of the Related Art For example, iron, aluminum, nickel,
In the case of obtaining a metal molded product 1 having a three-stage cylindrical shape as shown in a front view in FIG. 12A and a side view in FIG. Is
Normally, a columnar material 100 shown in a front view in FIG. 13A and a side view in FIG.
Alternatively, as shown in a sectional view in FIG. 14, the molten metal 201 is often cast into a mold 200 by high-pressure casting. In FIG. 12B, L indicates the axis of the molded article 1, and 1A indicates a plane orthogonal to the axis L.

Since the productivity is low in the above-mentioned cutting or casting, it is conceivable to increase the productivity and reduce the cost by manufacturing the molded article 1 by forging. What can be easily considered when forging the molded product 1 is a general female die for forging shown in a sectional view in FIG. The female die for forging of FIG. 15 has a female main body 303 (also referred to as a die) having a molding surface 303A that regulates the outer shape of the molded product 1, and reinforcement for holding the female main body 303 by press-fitting or shrink-fitting. And a ring 302. The molded article 1 is formed by pressing the metal material 1 a in the female mold body 303 with the lower punch 306 and the upper punch 307.

[0004]

According to the above-mentioned female mold for forging, when the metal material 1a is press-formed, the female mold main body 3 is formed.
The air confined in 03 is compressed by the lower punch 306 and the upper punch 307. But the air
Since there is no escape from the inside of the female mold body 303 to the outside of the mold, the material 1a in the middle of molding is locally peeled off from the molding surface 303A, thereby causing distortion in the molded article 1. In addition, when the pressing force is simply increased, there is a problem that a crack called "breaking" occurs in the female main body 303 due to a reaction force forcibly pressing the material 1a. For these reasons, conventionally, it is difficult to produce the molded product 1 by forging, so that it is currently necessary to produce the molded product 1 by cutting or casting.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to solve the problem that the air trapped in the female mold body during the pressure molding of the material is removed from the mold. It is an object of the present invention to provide a female die for forging which can be made to escape to prevent distortion of a molded product and generation of sharpness of a female die body.

[0006]

According to a first aspect of the present invention, there is provided a female mold body having a molding surface for regulating the outer shape of a molded product, and a holding ring for holding the female mold body. A female die for forging, wherein the female die body is divided into a plurality of divided bodies in an axial direction or a circumferential direction.
According to the female die for forging according to the first aspect, fine fine particles communicate with each other between divided surfaces of the plurality of divided bodies constituting the female die main body and between fitting surfaces of the female die main body and the retaining ring. Gaps are created. For this reason, the air trapped in the female mold main body during the pressure molding of the material can escape to the outside of the mold through the gap, thereby preventing the molded product from being distorted and the female mold main body from being distorted. .

According to a second aspect of the present invention, there is provided the female die for forging according to the first aspect, wherein the divided body is made of ceramic. According to the forged female mold ceramic divided body according to claim 2, even if the surface of the material to be processed is not subjected to a coating treatment such as lubricating oil, the material is compared with that of a super steel alloy. Does not occur under high-pressure and high-temperature conditions, and friction due to the fusion phenomenon is small.
Since the molding surface and the molded product are hardly damaged by galling or the like, a molded product having excellent durability and high quality can be obtained. Also, according to the ceramic divided body, since it is a non-magnetic body,
Since no static electricity is generated, adhesion of foreign matter due to static electricity can be prevented, so that the number of times of cleaning the molding surface can be reduced.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments 1 to 3 of the present invention will be described in order. Embodiment 1 Embodiment 1 will be described with reference to FIGS. The present embodiment is a female die for forging for forming the metal molded product 1 (see FIG. 12) described in the conventional example. In FIG. 2 showing an explanatory view of a female die for forging, FIG.
Is a plan view, and (b) is a front sectional view. In FIG. 2, the female die for forging includes a female main body 3 including three divided bodies 3a, 3b, 3c, and a holding ring 2 for holding the female main body 3.

FIG. 3A is a plan view of the holding ring 2,
As shown in the front sectional view of FIG. The holding ring 2 is made of a metal such as nickel chrome molybdenum steel (SNCM-8) steel, SK steel, or the like.

[0010] As shown in FIG.
Reference numerals a, 3b, and 3c denote a molding surface 3A that regulates the outer shape of the molded product 1 (see FIG. 12) in a set of a total of three upper, middle, and lower stages in the axial direction. The division plane (reference numeral 4 is attached) between the upper divided body 3a and the middle division body 3b and the division plane (reference numeral 5 is attached) between the middle divided body 3b and the lower divided body 3c are shown. 12 and the plane 1A orthogonal to the axis L of the molded article 1 shown in FIG. The upper divided body 3a is shown in FIG. 4, the middle divided body 3b is shown in FIG. 5, and the lower divided body 3c is shown in FIG.
Are respectively shown in explanatory diagrams. 4A to 6, (a) is a plan view, and (b) is a front sectional view. Each of the divided bodies 3a, 3b, 3c is made of, for example, Si ₃ N ₄ , ZrO.
_{2 and the} like, and is firmly assembled in the holding ring 2 by shrink fitting.

[0011] The material (code, 1
a is attached. 1), the material 1a is put into the female mold body 3, and the material 1a is put into the lower punch 6 and the upper punch 7 as shown in the sectional view of FIG.
Then, the molded article 1 (see FIG. 12) is molded by applying pressure. The lower punch 6 and the upper punch 7 are pressurized using a press machine as is well known.

According to the forging female mold described above, the female mold body 3
A minute gap communicating with each other between the divided surfaces 4 and 5 of the divided bodies 3a, 3b and 3c, and between the fitting surfaces (reference numerals 8) between the female body 3 and the holding ring 2 Can be. For this reason, the air trapped in the female mold body 3 during the pressure molding of the material 1a can be released to the outside of the mold through the gap, thereby preventing distortion of the molded article 1 and generation of sharpness of the female mold body 3. can do. This makes it possible to mass-produce the molded article 1 having a complicated shape with high accuracy and to manufacture it at low cost, while improving the durability of the female die for forging. The gaps 4 between the divided bodies 3a, 3b, 3c,
Reference numeral 5 denotes a minute gap of, for example, about several μm, which is not large enough for the material 1a to be formed by forging, so that the formed article hardly generates burrs.

Further, since each of the divided bodies 3a, 3b, 3c is made of ceramic, the surface of the material 1a to be processed is not treated with a coating agent such as lubricating oil, so that it is compared with that of a super steel alloy. As a result, friction due to the fusion phenomenon under high-pressure and high-temperature conditions with the material 1a is small, and the molding surface 3A and the molded product 1 are not easily damaged by galling or the like, so that the molded product 1 having excellent durability and high quality can be obtained. In addition, ceramic divided body 3
According to a, 3b, and 3c, since there is no generation of static electricity because it is a non-magnetic material, it is possible to prevent the adhesion of foreign matter due to static electricity,
Therefore, the number of times of cleaning the molding surface 3A can be reduced. The divided bodies 3a, 3b, 3c may be made of a super-steel alloy, hardened SK steel, or the like, instead of ceramic. In this case, each of the divided bodies 3a, 3b, 3c can be assembled into the holding ring 2 by press fitting instead of shrink fitting.

Further, each of the divided bodies 3a, 3b, 3c is formed by dividing surfaces 4A, 4A which are the same as the surface 1A orthogonal to the axis L of the molded product 1.
By dividing by 5, the molding surface 3A of each of the divided bodies 3a, 3b, and 3c has a simple shape as compared with the case of dividing by other parts, so that each of the divided bodies 3a, 3b, and 3c is easily manufactured. It is possible.

Second Embodiment A second embodiment will be described with reference to FIGS. The second embodiment and a third embodiment to be described later are modifications of the first embodiment, and therefore, only the changed portions will be described in detail, and redundant description will be omitted. This embodiment considers the case of forging a molded article 11 having a polygonal column shape (the figure shows a regular octagonal column) shown in a perspective view in FIG. 7, and a female mold body is shown in a perspective view in FIG. ing.

As shown in FIG. 8, the female mold body 13 is composed of eight divided bodies 13a equally divided in the circumferential direction. Dividing surface 1 between divided bodies 8a
Reference numeral 4 denotes the same plane as the surface on which the axis L of the molded product 1 shown in FIG. 7 and each side 11B of the molded product 11 parallel to the axis L are located.

According to this embodiment, the same operation and effect as those of the first embodiment can be obtained. In addition, each divided body 13a is
And each side 11 of the molded article 11 parallel to the axis L
By dividing by the dividing surface 14 which forms the same plane as the surface on which B is located, the molding surface 13A of each of the divided bodies 13a has a simple shape as compared with the case of dividing by another part. It can be easily manufactured.

[Third Embodiment] A third embodiment will be described with reference to FIGS. This embodiment considers the case of forging a hexagonal bolt-shaped molded product 21 shown in a perspective view in FIG. 9, and FIG. 10 is a cross-sectional view of a female die for forging, and FIG. An exploded perspective view is shown.
The molded product 21 shown in FIG. 9 includes a hexagonal prism-shaped head 21a and a shaft 21b. The female mold main body 3 shown in FIGS. 10 and 11 is divided into two upper and lower lower divided bodies 23a and an upper divided body 23b on the same plane as a plane 21A orthogonal to the axis L of the molded product 21 shown in FIG. Further, the upper divided body 23b is equally divided in the circumferential direction on the same plane as the surface on which the axis L of the molded article 21 and the side 21B of the molded article 21 parallel to the axis L are provided, thereby obtaining six divided bodies 23c. It is. According to this embodiment, the same operation and effect as those of the first and second embodiments can be obtained.

[0019]

According to the female mold for forging of the present invention, the air trapped in the female mold during the pressure molding of the material can be released, thereby preventing the distortion of the molded product and the generation of sharpness of the female mold body. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a female mold for forging according to a first embodiment in a state where a material is press-formed.

FIG. 2 is an explanatory view of a female die for forging.

FIG. 3 is an explanatory diagram of a retaining ring.

FIG. 4 is an explanatory diagram of an upper divided body.

FIG. 5 is an explanatory diagram of a middle divided body.

FIG. 6 is an explanatory diagram of a lower divided body.

FIG. 7 is a perspective view showing a molded product according to a second embodiment.

FIG. 8 is a perspective view of a female die body of a female die for forging according to a second embodiment.

FIG. 9 is a perspective view showing a molded product according to a third embodiment.

FIG. 10 is a sectional view of a female die for forging according to a second embodiment.

FIG. 11 is an exploded perspective view of the female die for forging.

FIG. 12 is an explanatory view showing an example of a molded product.

FIG. 13 is an explanatory diagram of a cutting material according to a conventional example.

FIG. 14 is a sectional view of the same mold.

FIG. 15 is a cross-sectional view showing the female mold for forging in a state of press-molding a material.

[Explanation of symbols]

 Reference Signs List 1 molded product 2 retaining ring 3 female mold body 3A molded surface 3a divided body 3b divided body 3c divided body 11 molded article 13 female mold body 13A molded surface 13a divided body 21 molded article 23 female mold body 23A molded surface 23a divided body 23b divided Body 23c divided body

Claims (2)

[Claims] 1. A female mold body having a molding surface for regulating the outer shape of a molded article, and a holding ring for holding the female mold body, wherein the female mold body is divided into a plurality of divided bodies in an axial direction or a circumferential direction. A female mold for forging characterized by being divided into two. 2. The female die for forging according to claim 1, wherein the divided body is made of ceramic.