JP2003266137A - Forging device, and forging method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a forging device to prevent occurrence of burrs as much as possible when forming a recessed part on a cylindrical side surface by pressing a punch against a stock. <P>SOLUTION: This forging device comprises a first punch 7 disposed in a die 1 in a vertically movable manner, a second punch 2 disposed at the position facing the first punch 7 in a vertically movable manner, a cavity 3 formed by the second punch 2 and the die 1, and a side punch 5 disposed movably in the cavity 3 via the die. When the side punch 5 presses the stock disposed in the cavity 3, both the first punch 7 and the second punch 2 also press the stock, and the pressing load of the second punch 2 is set smaller than that of the first punch 7. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forging apparatus and a forging method for a metal part having a recess on its side surface.

[0002]

2. Description of the Related Art A forging apparatus as shown in FIG. 7 is used when performing processing (embossing) for forming a recess 101 on a side surface of a cylindrical body 100 as shown in FIG. A side punch 5 is pressed against a bottomed cylindrical material (cup shape) 4 located in a cavity 3 surrounded by a die 1 and a knockout pin 2 to form a recess 4a on the side surface. The side punch 5 can be driven in cooperation with a cam die 6 arranged outside the die 1 and a tapered surface 5 a of the side punch 3. 7 is a punch for preventing deformation when forming the recess.

[0003]

When a lateral punch is extruded from the radial direction in order to form a recess in the above-mentioned cup-shaped or cylindrical material, the material extruded by pressing the punch into the material is Movement is hindered by friction with the punch and die. This makes it difficult to insert the side punch deeply, and at the same time, there is a problem that the material enters the clearance between the side punch and the die to generate burrs and damage due to die sticking.

[0004]

SUMMARY OF THE INVENTION The present invention has been made based on the above-mentioned problems, and it provides a first punch which is vertically movable in a die and a position where the first punch faces each other. Arranged up and down movable second punch, a cavity formed by this second punch and a die, and a side punch arranged so that it can be inserted into and removed from the cavity through the die, When the side punch presses the material arranged in the cavity, the first punch and the second punch also press the material, and the pressing load of the second punch is the first punch. The forging device is characterized by being set smaller than the above.

According to the present invention, when the lateral punch is inserted into the blank, the first punch is moved in the axial direction (downward) so that the volume of the lateral punch inserted into the blank is formed downward. It is possible to move the insertion punch smoothly and to facilitate the processing of the recess. At this time, since there is a risk that the side wall may be broken only by the first punch in the axial direction, by applying a load in the opposite direction to the second punch installed at the position opposite to the first punch, the punch is punched. It is possible to bring the material near the tip into a stress state close to hydrostatic pressure. As a result, it is possible to facilitate the downward flow of the material while suppressing the breakage of the side wall and facilitate the insertion of the side punch.

Further, the side punches are driven by a cam die which cooperates with a taper portion of the side punches arranged outside the die, whereby driving means such as a hydraulic cylinder is arranged in the axial direction. Therefore, the forging device can be set compactly.

Further, by making the diameter of the second punch smaller than the diameter of the first punch, it is possible to bring the second punch side into a stress state of rearward extrusion, causing downward material flow. Therefore, it is possible to absorb the insertion volume of the side punch into the material and suppress the occurrence of burrs.

Further, a step of disposing a cylindrical material having a bottom in the cavity, a step of inserting a first punch through an opening of the material, and a lateral punch of the material is driven to form a concave portion. When driving the side punch to press the material, the first punch and the second punch arranged at the position opposite to the first punch are also pressed to move the side punch to the side punch material. The forging method is characterized in that the pressing volume of is absorbed by the material flow due to the difference in pressing force between the first punch and the second punch.

In the present invention, as a microscopic processing step, when the side punch is inserted, the material extruded becomes a surplus. Almost at the same time or with a slight delay, the first punch moves downward, and it is possible to absorb the excess amount of the side punch. By repeating the generation of the excess thickness due to the insertion of the side punch and the absorption of the excess thickness due to the movement of the first punch, it becomes possible to form the concave portion without the occurrence of burrs. By applying the hydrostatic pressure by the second punch, it is possible to prevent the peripheral punch from shrinking when it is excessively moved in the axial direction.

Further, a step of arranging the material in the cavity, a step of driving the first punch toward the material to extrude the material backward to form a bottomed cylindrical body, and a step of forming the bottomed cylindrical body A step of driving a side punch from a side to form a concave portion, and driving the side punch to press a material, the first punch and a second punch arranged at a position opposite to the first punch. Also, the forging method is characterized in that the material is pressed and the pressing volume of the side punches to the material is absorbed by the material flow due to the difference in pressing force between the first punch and the second punch.

In the present invention, in addition to the above-described effects, the bottomed tubular body can be molded in one step, so that the molding efficiency can be improved.

Further, a step of punching out the material of the bottom portion of the bottomed cylindrical state by the cooperation of the first punch and the second punch is further added, and a metal part having a concave portion on the side surface of the cylindrical body is added in one step. Can be molded.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A detailed description will be given below with reference to FIGS.

2 to 6 show a recess 10 as shown in FIG.
It is explanatory drawing which shows the process for shape | molding the molded article 100 which has 1, and the sectional view in the LL line of FIG. 1 (a) is shown in (b) figure. The inner surface shown in FIG. 1 (b) is straight, but the outer surface is formed with a recess (emboss). The embossed shape can be molded into various shapes such as a sphere and a rectangle depending on the specifications required for the product. The arrows in FIGS. 3 to 6 indicate the driving directions of the punch and the die.

FIG. 2 is a view showing the initial state of forging.
Regarding the reference numerals, the reference numerals corresponding to those used in the description of FIG. 7 as the conventional technique are incorporated. A material 4 is placed in the cavity 3, and a first punch 7 stands by in the vertical direction of the material 4.

As shown in FIG. 3, first, the first punch 7
Is extruded toward the material 5, and the material 4 is extruded rearward to form a bottomed cylindrical body. At this time, the first punch 7
By applying a pressing force smaller than the pressing force (overweight) of the first punch 7 to the second punches 2 arranged at the opposite positions of, the tubular body can be formed without cracks in the side wall. ing.

Next, as shown in FIG. 4, when the bottomed tubular body 4 is extruded rearward to a substantially desired length, the side punch 5 movably arranged in the hole 1a of the die 1 is opened. It is extruded toward the material, and the recessed portion 4 is
a is formed. When the side punch 5 is driven by using a driving means such as a hydraulic cylinder (not shown) such as a hydraulic cylinder, the side punch 5 cooperates with the taper portion 5a of the side punch 5 to push the side punch 5 toward the material. I have to. At this time, the first punch 7 and the second punch 2 continue to press-form the material although the overweight is slightly reduced. For this reason, the material (extra thickness) extruded by inserting the side punch 5 into the material is the first punch 7 and the second punch 2.
The material is absorbed by the flow of the material, and it does not become a burr like in the past.

FIG. 5 shows that the recess 4a can be formed into a desired shape.
As shown in, the cam die 6 and the first punch 7 are returned to their initial positions. When the cam die 6 is returned to the initial position, the side punch 5 also retracts. Then, the cylindrical body 4 is pushed out by the second punch 2 and discharged from the die.

Although the side punch 5 is driven by using the cam die in the above embodiment, it may be connected to a driving means such as a hydraulic cylinder so as to directly drive the side punch 5. .

The formation position, number and shape of the recesses can be easily set by appropriately changing the shape of the side die.

The bottomed cylindrical body after molding is made into a cylindrical metal part by punching or cutting the bottom. When punching out the bottom, for example, the second punch is placed on the outside of the inner punch having the same outer diameter as the first punch, and the outer punch on the cylinder having the same thickness as the wall thickness of the molded body is arranged. The bottom part is sandwiched between the first punch and the second punch and is moved downward. At that time, the outer punch of the second punch can be punched out by staying on the spot without moving.

[0022]

According to the present invention, when the punch is pressed toward the raw material to form the concave portion on the side surface of the cylindrical body, the raw material extruded by the concave portion is absorbed by the material flow in the axial direction. Therefore, it is possible to provide a forging device capable of preventing the occurrence of burrs.

[Brief description of drawings]

1A and 1B are views showing a metal part molded according to the present invention, in which FIG. 1A is a schematic view, and FIG.
It is an L line sectional view.

FIG. 2 is a diagram showing a manufacturing process of an example of the present invention and a diagram showing an initial stage of forging.

FIG. 3 is a diagram showing a manufacturing process of an embodiment of the present invention, and a diagram showing a process of forming a tubular body by backward extrusion.

FIG. 4 is a diagram showing a manufacturing process according to an embodiment of the present invention, which is a diagram showing a process of molding a portion on the side surface of the concave tubular body.

FIG. 5 is a diagram showing a manufacturing process according to the embodiment of the present invention, which is a diagram showing the end of molding.

FIG. 6 is a diagram showing a manufacturing process according to the embodiment of the present invention, and a process showing a step of taking out a molded product.

FIG. 7 is a diagram for explaining a conventional problem, and FIG. 7B is an enlarged view of a circled portion in FIG.

[Explanation of symbols]

1 die 2 second punch 3 cavities 4 material 5 side punches 6 Cam Dice 7 first punch 100 metal parts 101 recess

Claims (6)

[Claims] 1. A first punch, which is arranged so as to be movable up and down in a die, a second punch, which is arranged at a position opposite to the first punch, which is vertically movable, and the second punch and the die. When a cavity formed by and a side punch that is removably arranged in the cavity through the die are arranged and the side punch presses the material arranged in the cavity, A forging device characterized in that the first punch and the second punch also press the material, and at that time, the pressing load of the second punch is set to be smaller than that of the first punch. 2. The forging device according to claim 1, wherein the side punch is driven by a cam die which cooperates with a taper portion of the side punch arranged outside the die. 3. The forging device according to claim 1, wherein the diameter of the second punch is smaller than the diameter of the first punch. 4. A step of arranging a cylindrical material having a bottom in a cavity, a step of inserting a first punch through an opening of the material, and a lateral punch of the material is driven to form a concave portion. When driving the side punch to press the material, the first punch and the second punch arranged at the position opposite to the first punch are also pressed to move the side punch to the side punch material. The forging method is characterized in that the pressing volume of is absorbed by the material flow due to the difference in pressing force between the first punch and the second punch. 5. A step of disposing a material in the cavity, a step of driving a first punch toward the material to extrude the material backward to form a bottomed tubular body, and a step of forming the bottomed tubular body. A step of driving a side punch from a side to form a concave portion, and driving the side punch to press a material, the first punch and a second punch arranged at a position opposite to the first punch. Also, the forging method is characterized in that the pressing volume of the side punch to the material is absorbed by the material flow due to the difference in pressing force between the first punch and the second punch. 6. The step of punching out the material of the bottom portion in the bottomed tubular state by the cooperation of the first punch and the second punch,
The forging method according to claim 4, wherein the forging method is added.