JPH0364204B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a processing method for forming an axial groove in a pipe material by press working.

(Prior technology) For products made of aluminum, it is well known that axial grooves or protrusions are formed by extrusion or drawing, but when the material is iron, press processing is used. Grooves are often formed by

For example, if a product shape 1 as shown in FIG. 5 is to be obtained from a pipe material, the mold needs to have the same shape as the internal shape of the product. FIG. 7 shows a die according to the prior art, in which the die 2 is formed into a rectangular plane, and an axial groove 3 is provided on the opposing side walls, and the die 2 corresponds to the groove 3 and has a groove 3 extending in the axial direction. A punch 4 that moves forward and backward is provided. After the pipe material 5 is set outside the die 2, the punch 4 is pushed into the groove 3, thereby forming the groove 1a in the material 5.

In the above conventional technology, the bending width b of the product and the R of the die groove are regulated by the thickness of the material, and the balance of material drawing is likely to be lost depending on the condition of the die R, and the product shape and accuracy can be maintained. It is difficult to bend, the processing load increases depending on the bending width dimension b of the product, the material always slides on the R part of the die and is drawn into the concave groove, so the die is subject to severe wear. has many problems, including being easily scratched.

(Problem to be Solved by the Invention) The problem to be solved by the present invention is to use a split core metal and a knife-shaped bending punch to bend the pipe material in the axial direction. An object of the present invention is to provide a processing method for forming grooves.

(Means for solving the problem) Means for solving the problem in the present invention are as follows:
A pair of core metals are installed facing each other and are spaced apart from each other by a distance twice the depth of the groove to be formed into the product, and a pair of core metals are installed facing each other in a direction perpendicular to the opposing positions of the core metals. A knife-shaped bending punch is provided so as to be movable toward the center of the mold, and after the pipe material is set outside the core metal, the bending punch is moved toward the center of the mold. A first bending step of bending a V-groove in the side wall of the pipe material by moving the core metal toward the center of the mold under no load as the material deforms at the same time as the pipe material is being moved; A second bending step of moving the core bar toward the center of the mold while keeping the bending punch in contact with the groove portion of the processed portion to form a concave groove in the side wall of the pipe material. It is characterized by being molded.

(Example) FIGS. 1 to 3 are diagrams for explaining the steps of the processing method of the present invention. A pair of core metals 10 are provided at positions facing each other, and a slider 11 is in contact with the back surface of each core metal 10. Further, a pair of knife-shaped bending punches 12 are provided in a direction perpendicular to each of the core metals 10, and both are provided so as to be movable toward the center of the mold.

A first cam 13 is provided on the back of each bending punch 12, and a second cam 14 is provided on the back of each slider 11. The first cam 13 and the second cam 14 are attached to the upper die of a press slide (not shown), and when the slide is lowered, the first cam 13 moves the bending punch 12 first, and then the second cam 14
is installed at the timing when the slider 11 is moved.

When installing the core metals 10, each core metal 10 should be installed at a distance twice the depth of the groove to be formed in the product, and when the pipe material 15 is set outside the core metal 10, In order to position the material, it is preferable to urge it outward with a weak spring (not shown) in the backward direction. In addition, the inner dimensions of the material and the outer dimensions of the core bar 10 should have a margin that allows the material to be easily set, and furthermore, when the slider 11 is retracted, the material 15 should be spaced between it and the core bar 10. The positional relationship is good so that there is a gap for insertion.

FIG. 1 shows a state in which the material 15 is set outside the core metal 10 and ready for processing, and as the slide descends, the first cam 13 first comes into contact with the bending punch 12 and bends the punch 12. Move toward the center of the mold. The core bar 10 moves toward the center of the mold by the amount that the material 15 is drawn in by the bending punch 12, and as a result, the cross section V
A groove semifinished product 16 is formed (FIG. 2).

In addition, bending punch 12 for material 15
Since it is V-bending while moving, only a small machining load is required during this time, and the core metal 1 corresponding to the die
0 moves, no slippage occurs between the material and the core metal 10.

Next, the material 1 is
5 is bent into a V groove, the second cam 14
contacts the slider 11. After the second cam 14 comes into contact with the slider 11 by setting the angle of the cam, the slider 11 performs the forming, and the side wall of the material 15 is clamped by the core metal 10 and the slider 11. Although the bending punch 12 does not directly participate in molding while the slider 11 is in operation, it is moved further toward the center of the mold by the first cam 13.

When the press slide reaches the bottom dead center in the state shown in FIG. 3, the core metal 10 and the bending punch 12 are in close contact with each other through the material, so that the portion bent into the V groove is the bending punch 12. The material 15 is compressed by the core metal 10 to form a concave groove along the axial direction in the material 15 with the required R dimension and product accuracy.

When the press slide passes the bottom dead center and reaches the top dead center to complete one process, the slider 11 and bending punch 12 return to the position shown in FIG. Take out.

The product manufactured by the above processing has the same shape as the product shown in FIG.

FIG. 4 shows a process sequence for processing products having other shapes by applying the processing method of the present invention.
A square pipe material 20 is formed into a semi-finished product 22 having grooves 21 on opposing surfaces in a first bending process, and then into a product 24 having grooves 23 in a surface perpendicular to the grooves 21 in a second bending process. Molded.
Since the first bending process to obtain the semi-finished product 22 in this processing process has the same shape as the product in FIG.
It may be rectangular as shown in the figure, but semi-finished products 22
When processing a blank into a product 24, four square core metals 25 are used and set at each corner of the semi-finished product 22. However, as shown in FIG. 4A, it goes without saying that the square core metal 25 can be used in advance from the time of the first bending process.

(Effects of the Invention) The present invention can form an axial groove in a pipe material only by bending, so the groove can be formed with a small processing load, which prevents damage caused by wear of the mold and improves the quality of the product. It has the effect of not getting scratched.

[Brief explanation of drawings]

1 to 3 are process diagrams sequentially explaining the processing steps of the present invention, Figures 4A to C are process diagrams of forming materials in other products to which the method of the present invention is applied, and Figures 5 and 3 are FIG. 6 is a perspective view of the product, and FIG. 7 is a plan view of a die according to the prior art. 10... core metal, 11... slider, 12... bending punch, 13... first cam, 14...
Second cam, 15...pipe material, 16...semi-finished product, 17... finished product.

Claims (1)

[Claims] 1 A pair of core metals installed facing each other and separated by a distance twice the depth of the groove to be formed into the product, and a pair of core metals installed facing each other in a direction perpendicular to the opposing position of the core metals. A knife-shaped bending punch is provided so as to be movable toward the center of the mold, and after the pipe material is set outside the core metal, the bending punch is moved toward the center of the mold. a first bending step of bending a V-groove on the side wall of the pipe material by moving the core metal toward the center of the mold under no load as the material deforms; a second bending step in which the bent portion is moved toward the center of the mold while the bending punch is abutted against the groove, and a concave groove is bent on the side wall of the pipe material; A method of forming an axial groove in a pipe material, which is characterized by forming an axial groove in a pipe material.