JPH07164090A - Formation of forged product with hole - Google Patents

Abstract

PURPOSE:To rationally execute the piercing of a forged product with hole by removing the obstacle by a burr at the time of piercing. CONSTITUTION:At the time of forming the forged product 10 provided with holes 23, 24 opened to the parting surfaces of the upper and the lower dies for forging even in a part of holes, at first, a blank is pressed in between the upper die and the lower die to form the rough forged product 1 with burrs. Only the burrs which interfer with the opening surfaces 21, 22 of the holes in the projecting burr 3 over the whole circumference are removed. The remaining burrs 31, 32 are held to execute handling and the necessary shifting and posture turning of a work are executed, and after piercing the prescribed position, the remaining burrs are removed in order. If the whole burr is removed, there is no holding position during forging, and as the handling is made to be difficult, the piercing by machining is forced to execute, but the piercing can rationally be executed by a series of forging piercing, and the utilization of heat energy and the improvement of the productivity are remarkably made to be high.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forming method by forging, and more particularly to forming a forged product with a hole having a hole in the shape after the forming.

[0002]

2. Description of the Related Art In order to mass-produce rough forged products efficiently, when forming a material by pressing it between upper and lower molds, the treatment of burrs on the divided surfaces is a major factor. When the upper and lower molds are combined, the burr is completely filled with the material charged into the cavity provided inside, and the shape of the mold cavity is accurately transferred to the material, and the rest is the split surface. Since it extends as extra thickness, it can be said that it is unavoidable for forming a precise shape. Of course, this burr needs to be removed in a later process, so there is one side that requires extra work, but if it cannot be avoided, there are also attempts to actively use it to help streamline the process. .

For example, in the prior art disclosed in Japanese Patent Laid-Open No. 3-23026, in a two-piece forging method for producing two forged products of the same type from rough forging to finish forging, one forging commonly used in the past has been used. 2 pieces were obtained by placing the material and taking 2 pieces, but by rough forging with 2 heated preliminary rough forgings placed in the rough forging molding cavity, and joining the burr part integrally It proposes a molding method in which one set of rough forged products is molded and then finish forged. As a result, the yield of expensive materials is significantly improved, and it is possible to perform rough forging with a small forging device because of its molding ability, and it is easy to handle during forging.

Not limited to this conventional technique, generally formed rough forged products are pushed up from below by a knockout pin penetrating the lower die, and when the rough forged product slightly with burrs floats up from the dividing surface, the dividing surface and the bottom surface of the burr are formed. It can be used for handling of inserting a transfer bar finger tip into the gap between and and gripping a rough forged product with burrs and transferring or inverting it to a desired position. Or, even if it is not a transfer press, you can insert fire chopsticks etc. into this gap and grasp the rough forged product with burr effectively, so the burr is an indispensable role at the stage of handling the intermediate rough forged product heated to high temperature. It is no exaggeration to say that they are fulfilling. That is, the formed forged product body maintains the temperature at which hot forging can be performed, but the overhanging burr extends between the dies with a substantially uniform thin wall thickness, so it is rapidly cooled to support the entire body. The burr becomes an indispensable essential part in the transportation of the intermediate process of forging because it has enough strength as soon as possible.

[0005]

The forged products include a large number of forged products. Of course, there are cases where the holes are punched by machining after molding, but there are not a few cases where holes are punched (piercing). In any case, if the axis of the hole is at a right angle to the dividing surface of the mold, burr does not extend to the outer surface to be drilled,
There is no particular problem with machining or piercing. However, in many cases, naturally, many shapes in which the axis of the hole to be drilled is parallel to the dividing surface are included. Even if the axes are not parallel but oblique, if the burr is protruding to the position of the hole to be drilled, it will interfere with the drilling tool and interfere with normal work. For example, there is a problem in that it cannot proceed to the next punching process.

However, the cutting of the burr as described above deprives the handling means directly required for the subsequent forging process, and is extremely disadvantageous for moving and reversing the rough forged product. For example, assuming that the rough forged product 1a with a burr shown in FIG.
If the burr 3a along the entire circumference is cut off uniformly, the figure (B)
Although a burr-free molded product can be obtained as in the above, since all burr is lost, even if the rough forged product that is still inserted in the lower mold is knocked out and floated from the split surface, There is no way to insert the fingers, resulting in confusion in transportation. After all, after removing the burr on the entire circumference, I gave up drilling (piercing) using a press because of the difficulty of changing the position and changing the posture, and after cooling, drill with mechanical drilling with a drill or use a special jig. There is no other way but to prepare and handle it. For example, as shown in FIG.
By the steps up to (D), means for selecting only the procedure for obtaining the forged product 10a with holes remains. This is
It is nothing but the abandonment of the opportunity to complete the punching forming with high efficiency by heating the bent material to a temperature at which it can be formed.

FIG. 6A and FIG. 6B show one of the prior arts which have dealt with this problem.
No. 41 publication. That is, in order to forge a suspension arm 10b having a hole as shown in FIG. 6B, a core 10 for forming a hole portion as shown in FIG.
This is a method of casting a cast product 1b in which 1 is cast, forging the core in the state of being cast, and then removing the core. According to this manufacturing method, since the undercut portion is formed as in the conventional case, it is not necessary to perforate the forged product, which reduces the number of steps and improves the material yield. In any case, with this method, even if the burr 3b formed by forging extends over the entire circumference of the dividing surface, since the hole itself does not need to be drilled, the burr does not hinder the molding. . However, generally requiring a casting process close to the shape of a forged product is not only a casting process but also a maintenance process for removing the core, which is troublesome due to the movement of the material. It must be said that if the casting process has a sufficient punching forming capability and goes through a different procedure without making full use of the capability, the material cost will rise sharply.

In order to solve the above problems, the present invention aims to provide a method for forming a forged product with a hole in which an obstacle to the burr during drilling is removed while maintaining the usability of the burr during handling in an intermediate step. And

[0009]

According to the method for forming a forged product with holes according to the present invention, the shape after molding has a shape having a hole at least a part of which is opened to the dividing surface of the upper die and the lower die. On the other hand, the forging material is pressed between the upper mold and the lower mold to form the rough forged product 1 with burrs, and among the burrs extending to the split surface over the entire circumference, burrs that interfere with the hole opening. The above problem was solved by removing only 3 in-situ, punching the desired position, and then removing the remaining burr.

[0010]

The molding method of the present invention selectively removes only the burrs on the surface that interfere with each other during perforation, and uses the remaining burrs to handle the rough forged product with burrs to change the position and posture,
The desired effect is achieved by the procedure of completing the desired drilling and then removing the remaining burr.

[0011]

Embodiment An embodiment of the present invention will be described with reference to steps (A) to (E) of FIG.
For example. The shape of the target forged product 10 with holes is shown in FIG.
Is the same as. In FIG. 1A, the rough-formed rough forged product 1 with burrs is formed of a forged product main body 2 and burrs 3 extending over the dividing surfaces of the upper die and the lower die. In this posture, only a part of the burrs is removed on the press, and burrs 31 and 32 left on the division surface and the removed burr mark 4 are generated as shown in FIG. The burr mark 4 is cut off so that at least the outer surface at the position where the hole should be drilled becomes a smooth surface. At this point, the forged product main body 2 is still in the lower mold, so the knockout pin is pushed up from below through the lower mold, and the finger is inserted into the gap between the mold faces which is slightly generated. , Or in the case of manual work, insert the chopsticks to hold the remaining burrs 31 and 32, take out the rough forged product 1 with burrs and move it, and at the same time flip the posture at a right angle to make the perforated surfaces 21 and 22 horizontal. Convert to keep. After the posture has been changed, the material still maintains a sufficiently moldable temperature, so that the desired holes 23, 24 are made in the drilling surfaces 21, 22 in the punching press as step (C). Perform a piercing operation. After perforation, the rough forged product with burr 1 was reinserted into the original molding die and left behind.
If the steps 1 and 32 are removed as the procedure (D), the forged product 10 with holes shown in FIG.

FIG. 2 shows another embodiment corresponding to the prior art. Figures (A) to (E) show the embodiment of the present invention, and Figures (b) and (c) show the procedure according to the prior art. The rough forged product 1A with burrs includes a forged product main body 2A and burrs 3A extending over the entire split surface. It is possible to punch from directly above the punching surface 22A facing the pressing direction in this posture, but for the punching surface 21A that interferes with the dividing surface,
Cannot be pierced. In the embodiment, the burr mark 4A is formed by removing only the burr orthogonal to the perforated surface 21A in the same posture as shown in FIG.
A and 32A are left as they are, the burrs are used to pull out the rough forged product 1A from the lower die, and the holes 23A are pierced and pierced in the piercing surface 22A in that posture. This is the stage of Fig. (B), and the burrs 31A and 3 left next are
2A is grasped and the whole body is rotated at a right angle, and the perforated surface 21
After changing A to a horizontal position, a hole 24A is punched to obtain a forged product with a hole 10A as a product of FIG. FIG. 6B shows a procedure according to the conventional technique for comparison, showing a state in which one hole 123a is pierced and deburred all around, and thereafter, the hole 1a is machined after cooling.
The process of perforating the hole 24a to reach the forged product with a hole 110a is illustrated.

FIG. 3 shows an embodiment in which two workpieces are taken. The forged product body 2B is a rough forged product 1B with burrs integrally connected by the remaining burrs 31B. Burrs that interfere with the perforated surfaces 21B and 22B are removed to form burr marks 4B. From the state shown in the figure, the remaining burrs are grabbed by the piercing press, inverted, moved and inserted into the mold, and punched by the piercing action from directly above, as in the previous two examples.

FIG. 4 shows a specific example of the case where the posture of the rough forged product 1B with burrs is rotated for punching from the state of the previous figure, and the beam which repeats the three-dimensional movement of the transfer press as shown in FIG. 5A, 5B clamping device 51A,
51B is used to grab the burrs 32B projecting on both ends, and the beam acts to change the posture by 90 degrees to the state of FIG. (B). Indicates immediately before.

[0015]

As described above, according to the present invention, as is often experienced, it is possible to eliminate the difficulty regarding the shape of the forged product, which needs to be punched in the die dividing surface, and change a part of the working procedure to remove the deburring. With only a minor change that divides the blade into two steps, it is easy to form a forged product with a hole that was extremely difficult in the past and could not be handled by machining or without a special jig. As a result, there is a great effect that the waste of heat energy, which has conventionally been unavoidably dependent on the machining after cooling, is retained while maintaining the temperature at which the piercing is possible, and the molding work with high efficiency is improved.

[Brief description of drawings]

1A to 1E are a perspective view and a step name showing a procedure of an embodiment of the present invention according to FIGS.

FIG. 2 is a perspective view and step names showing symmetrically the procedure of another embodiment of the present invention and the prior art by (A) to (E), (b) and (c).

FIG. 3 is a perspective view showing still another embodiment of the present invention.

4 (A) and 4 (B) are perspective views showing the operation of the embodiment of FIG.

5 (A), (B), (C), and (D) show a procedure of the prior art by a perspective view and step names.

FIG. 6 is a perspective view showing a conventional technique by (A) and (B).

[Explanation of symbols]

 1 Rough forged product with burr 2 Main body of forged product 3 Burr 4 Burr mark 5 Beam 10 Forged product with hole 21 Perforated surface 22 Perforated surface 23 Hole 24 hole 31 Burr 32 Burr

Claims (1)

[Claims] 1. A method for molding a forged product having a hole having at least a part opened to a divided surface of an upper mold and a lower mold after molding, wherein a forging material is pressed between the upper mold and the lower mold. A rough forged product 1 with burrs is formed, and among burrs extending on the divided surface over the entire circumference, only burrs that interfere with the hole opening are removed on the spot, and a hole is punched at a desired position. After that, a method for forming a forged product with a hole is characterized in that the remaining burr is removed.