JP2001276950A - Forging equipment - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To form a relatively long product whose entire length is regulated without deforming the inner diameter of a hollow material by one-step press forging. SOLUTION: A material 1 is set in an apparatus, a punch 5 of an upper die 6 is lowered, and the material 1 is pressed into a die 2 of a lower die 4, and the entire length is regulated by the punch 5 and the counter punch 3, and molding is performed. At this time, the first mandrel 7 is inserted into the hollow portion 1a of the material 1 from the upper end side and the second mandrel 9 is inserted from the lower end side, so that the entire length of the material 1 can be reduced without deforming the hollow portion 1a. Forming with the outer shape restricted. This makes it possible to finish the entire length, outer shape, and inner diameter of a long hollow product in one step, thereby improving production efficiency and reducing product cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forging device for preventing deformation of a hollow portion when forging a long hollow material.

[0002]

2. Description of the Related Art Generally, in order to form a long hollow product,
It is necessary to go through a multi-step process using a double-acting press or the like, and there is a problem that the production efficiency is reduced due to an increase in processing time. To cope with this, Japanese Patent Application Laid-Open No. Hei 5-7922 discloses that a press-forging is performed while pressing and fixing a mandrel for forming the inner diameter of a hollow material against a bolster, thereby preventing the mandrel from being broken or broken. A technique of extruding a pipe-shaped article with a reduced inner diameter and outer shape has been disclosed.

[0003]

However, the molding according to the prior art described above is an extrusion process in which the overall length of the material is not restricted, and the overall length and outer shape of the hollow material are restricted by a single-step impact using a single-acting press. When molding by molding, it is inevitable that the hollow portion of the material is deformed.

In this case, even if the mandrel is inserted into the hollow portion of the material while pressing and fixing the mandrel to a bolster or the like as in the prior art, a long material may bite into a molded product due to the falling of the mandrel, The malfunction that knock-out cannot be performed from the mold occurs.

[0005] Therefore, conventionally, in a single-step press forging in which the total length and outer shape of a hollow product are regulated, the length that can be formed is limited, and only a product having a relatively short total length can be formed.

The present invention has been made in view of the above circumstances, and provides a forging device capable of forming a relatively long product whose entire length is regulated without deforming the inner diameter of the hollow material by one-step press forging. It is intended to provide.

[0007]

In order to achieve the above object, an invention according to claim 1 is a forging apparatus for forming a forged product in which a hollow material is press-forged in one step to control a total length and an outer shape. A first mandrel is provided on the punch side for regulating the upper end of the hollow material, and a second mandrel is provided on the counterpunch side for regulating the lower end of the hollow material. The first mandrel and the second mandrel are inserted into the hollow portion of the hollow material so as to face each other.

That is, according to the first aspect of the present invention, when forming the hollow material, the first mandrel provided on the punch side for regulating the upper end of the hollow material and the counterpunch side for regulating the lower end of the hollow material are provided. By inserting the provided second mandrel into the hollow portion of the hollow material facing each other,
The material is formed by controlling the overall length and outer shape of the material by one-step press forging while preventing deformation of the hollow portion.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 relate to a first embodiment of the present invention. FIG. 1 is a configuration diagram of a main part of a forging device, and FIG. 2 is a cross-sectional view showing an example of a material.

FIG. 1 shows a single-acting press-type forging device capable of forming a product having a restricted overall length and outer shape without deforming a hollow portion from a long hollow material. 2 and a counter punch 3 which regulates the lower end of the material 1 and pushes out the molded product from the die 2.
A lower die 4 having a die 2 and a die 2
And an upper die 6 for holding a punch 5 pressed inward.

Hereinafter, in the present embodiment, as shown in FIG. 2, for the material 1 having a hollow portion 1a with a stepped outer peripheral portion having a different diameter, the overall length and outer shape are regulated without deforming the inner diameter of the hollow portion 1a. An example of forming by molding will be described.

The upper die 6 is moved up and down by a single-acting cylinder (not shown), and the lower die 4 and the upper die 6 are fitted concentrically when descending. A first mandrel 7 is slidably fitted in the center of the shaft. The first mandrel 7 is provided in the axial direction as an escape when the small diameter portion 7a inserted into the hollow portion on the upper end side of the material 1 and a second mandrel 9 described later facing the first mandrel 7 are abutted. A large diameter portion 7b movably inserted into the upper portion of the punch 5 with a predetermined stroke, and a spring 8 for urging the first mandrel 7 in the direction of the lower mold 4 is interposed at the upper end of the large diameter portion 7b. Have been.

On the other hand, a counter punch 3 is slidably inserted in the die 2 of the lower die 4 under a stepped shaped portion 2a of an irregular shape for forming the outer periphery of the raw material 1.
While reducing the outer shape of the material 1 with the die 2
The whole length of the raw material 1 is reduced to a specified length by the punch 5 of the upper die 6 and the counter punch 3 of the lower die 4 and then molded.

The counter punch 3 comprises a sliding portion 3a which slides in the die 2 in the axial direction and a base 3b having a larger diameter than the sliding portion 3a, and the lower end face of the base 3b of the counter punch 3 is a lower die. Abuts on the plate 10 fixed to the
The load from the punch 5 is received.

Further, at the center of the axis of the counter punch 3,
A second mandrel 9 which is inserted into the hollow portion of the material 1 from the lower end side and opposes the first mandrel 7 is slidably inserted therein. The lower end of the second mandrel 9 has a hole in the center of the plate 10. And is fixed in contact with the central part of the plate 11 disposed at the lower stage of the plate 10.

The plates 10 and 11 are members for supporting a plurality of knockout pins 12 that push up the lower end face of the counter punch 3. The plate 10 has a central hole through which a large diameter head of the knockout pin 12 is inserted. The plate 11 is provided with a hole through which the small-diameter pin body of the knockout pin 12 is inserted. An ejector 13 connected to a driving mechanism (not shown) is provided below the knockout pin 12.

That is, the head of the knockout pin 12 is inserted into the plate 10 which comes into contact with the end face of the counter punch 3 and is prevented from falling off by the plate 11. After the molding is completed, when the ejector 13 rises with the rise of the upper mold 6, Counter punch 3 via knockout pin 12
Is pushed up, and the material 1 is pushed out of the die 2.

In the forging apparatus having the above structure, the blank 1 is set in the apparatus, the punch 5 of the upper mold 6 is lowered, and the blank 1 is pressed into the die 2 of the lower mold 4, and the punch 5 and the counter punch 3 are pressed. The step of shaping while regulating the total length is performed in one step.

At this time, the first mandrel 7 is inserted into the hollow portion 1a of the raw material 1 from the upper end and the second mandrel 9 is inserted from the lower end, and the first mandrel 7 is urged by the spring 8. Are arranged so as to press the second mandrel 9, so that the inner diameter of the hollow portion 1a of the material 1 can be regulated and the entire length and outer shape can be regulated.

In addition, even if the material 1 is long, the first mandrel 7 and the second mandrel 9 are both short, so that the material 1 does not bite due to falling, and the material 1 can be used. After molding, the upper die 6 is raised to eject the ejector 1
Also, when the counter punch 3 is pushed up through the knockout pin 12 to knock out the material 1 from the die 2, the material 1 can be pushed out of the die 2 without any trouble.

Thus, it is possible to finish the entire length, outer shape, and inner diameter of a long hollow product in one process only by improving the ordinary press forging machine, thereby improving production efficiency and reducing product cost. Can be planned.

Also, the hollow portion 1 of the material 1 finally formed is
Even when a is cut with a drill or the like, since the pilot hole can be formed with high precision, the drill does not escape in the process of exposing the hole diameter, and it is possible to perform precise processing and improve the finishing accuracy. it can.

FIG. 3 relates to a second embodiment of the present invention.
It is a principal part block diagram of a forging apparatus.

The forging device according to the second embodiment includes a first mandrel 7 and a second mandrel 9 according to the first embodiment.
Each of the upper and lower ends of the hollow portion 1a of the raw material 1 is reduced to a length that allows the first and second mandrels to penetrate to a predetermined depth, so that the first mandrel and the second mandrel do not abut each other.

That is, during molding while regulating the overall length and outer shape of the raw material 1, the places where the inner diameter of the hollow portion 1 a may be deformed are the upper end side where the punch 5 of the upper die 6 receives large stress, and the lower die side. 4 is a lower end side subjected to a large stress by the counter punch 3.

Therefore, as shown in FIG. 3, the first mandrel 14 and the second mandrel 15 in the second mode are provided.
Reduces the first mandrel 7 and the second mandrel 9 in the first embodiment to a minimum length necessary to prevent deformation at the upper end and the lower end of the hollow portion 1a of the raw material 1 during molding, The first mandrel 14 is fixed to the upper mold 6 and the spring 8 is eliminated.

In the second embodiment, similarly to the first embodiment, the deformation of the hollow portion can be prevented when the long hollow product is formed while regulating the entire length and outer shape thereof. By molding the overall length, outer shape, and inner diameter of the product, it is possible to reduce product cost by improving production efficiency.

[0028]

As described above, according to the first aspect of the present invention, when forming the hollow material, the first mandrel provided on the punch side for regulating the upper end of the hollow material, and the lower end of the hollow material. By inserting a second mandrel provided on the counter punch side for regulating the part into the hollow part of the hollow material while facing each other, the entire length and the outer shape of the material are formed by one-step press forging while preventing the deformation of the hollow part. , So that it is possible to mold a relatively long product whose length is regulated without deforming the inner diameter of the hollow material by one-step press forging, thereby improving production efficiency and reducing product costs. Can be achieved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a main part of a forging device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an example of a material according to the first embodiment;

FIG. 3 is a configuration diagram of a main part of a forging device according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Material (hollow material) 1a ... Hollow part 3 ... Counter punch 5 ... Punch 7 ... First mandrel 9 ... Second mandrel

Claims (1)

[Claims] 1. A forging device for press-forging a hollow material in a single step to form a forged product having a regulated overall length and outer shape, wherein a first mandrel is provided on a punch side for regulating an upper end portion of the hollow material. At the same time, a second mandrel is provided on the counterpunch side that regulates the lower end of the hollow material. During the molding of the hollow material, the first mandrel and the second mandrel are opposed to each other to form the hollow material. A forging device characterized by being inserted into a hollow part.