JPH0810865A - Device for finishing circumferential face of press article and method therefor - Google Patents

Abstract

PURPOSE:To obtain a press article which acts surely by forming an inclining face to make a prescribed angle against the moving direction of a punch at a corner part of a top end face of the punch and a shearing side face, and making a major part of the circumferential face smoothly. CONSTITUTION:An inclining face to make an angle alpha of 30+ or -5 deg. against the moving direction of a punch 2 is installed at a corner part of a top end face of the punch and a shearing side face 9. A material to be worked 3 is placed on the upper face 4 of a die 1 so as to make the working tolerance 7 to project from an edge 6, and the working tolerance 7 is cut down by moving the punch 2 down. Therefore, the working tolerance 7 of the material to be worked 3 is slipped downward with the edge 6 of the die 1 and the edge 11 of the punch 2, the smooth shearing face is formed without generating the broken face, and the press article with the excellent appearance is obtained. Further, because the clearance B of the die 1 and the punch 2 is enough as well as the same degree of a general punching press, the life of the die is made long.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a finishing apparatus and method for finishing a peripheral edge of a pressed product obtained by punching and pressing a metal plate to obtain a squareness of a draft.

Generally, a plate-shaped metal product is formed by punching from a metal plate, but the peripheral edge of this type of pressed product is
About 30 to 40% of the thickness forms a smooth smooth surface, but the remaining 60 to 70% has a rough fracture surface.

That is, when punching a metal plate with a die and a punch in a punching press, a shearing force acts on the metal plate. Then, in the initial stage of the shearing, the punch advances into the material and the shearing progresses, but since there is a clearance between the die and the punch in the middle of the shearing, the material breaks at a stretch between the edge of the die and the punch. As a result, a pressed product having a predetermined shape can be obtained.

Therefore, a smooth and smooth surface is formed on the peripheral surface of the portion where the metal plate is deformed by shearing by the die and punch, but the broken surface of the portion where the material is broken at once becomes rough.

When the press product obtained as described above is used as various mechanical parts, etc., when the peripheral surface of the press product is subjected to some action, there is the above-mentioned rough fracture surface. Various malfunctions may occur, such as uncertain operation and non-sliding with other parts.

[0006]

2. Description of the Related Art A fine blanking method or the like is known as a pressing technique that does not cause the fracture surface, but the clearance between the die and the punch is extremely small. It requires extremely high precision die, and the impact stress at the time of punching is large, resulting in poor die durability.

A technique for smoothing the peripheral surface of a pressed product by shaving is also known, but in this method, the die is extremely complicated and the processing cost is high.

The present invention has been made in view of the above circumstances, and can be processed as a part of a normal punching press process, and high smoothness such as fine blanking and shaving cannot be obtained. However, it is an object of the present invention to provide an apparatus and method for finishing the peripheral surface of a pressed product, which is capable of obtaining smoothness to the extent that it can operate sufficiently smoothly as a normal machine part.

[0009]

The peripheral surface finishing device of the present invention comprises a die and a punch that slides along the shearing side surface of the die, and the corners between the tip surface and the shearing side surface of the punch. In addition, an inclined surface of 30 ± 5 ° with respect to the moving direction of the punch is formed.

The angle of the inclined surface in this apparatus is preferably 30 ± 2 ° with higher accuracy.

Further, in the peripheral surface finishing method of the present invention, the work material is placed on the die, and the machining allowance of the work material is projected from the upper edge of the shearing side surface of the die so that the tip surface and the shearing side surface are separated from each other. It is characterized in that the machining allowance of the material to be machined is cut off by a punch having an angled surface with an angle of 30 ± 5 ° with respect to the sliding direction.

In this method, it is preferable that the width of the inclined surface of the punch in the direction perpendicular to the sliding direction is larger than the protruding width of the machining allowance of the workpiece.

FIG. 1 shows a peripheral surface finishing apparatus of the present invention, in which 1 is a die, 2 is a punch, and 3 is a work piece placed on the die 1.

The die 1 has an edge 6 formed at the corner between the upper surface 4 and the shearing side surface 5, and the work material 3 has a machining allowance (white) 7 cut off for finishing. It is placed so as to project from 6.

The punch 2 is adapted to reciprocate with respect to the die 1 in the direction of arrow A, and the corners of the tip surface 8 and the shearing side surface 9 are cut off to form an inclined surface 10.
Is formed, and an obtuse edge 11 is formed at a corner between the inclined surface 10 and the movable plate 9. The angle α formed by the inclined surface 10 with respect to the moving direction is about 3
It is 0 °.

The range for setting this angle α is 30 ± 5 °
Should be set within the range of, preferably 30 ± 2 °, and even more preferably 3 as accurately as possible.
It is preferably 0 °.

If the angle α is too large, a fractured surface is produced in a large range on the peripheral surface of the finished work material 3, and a sufficiently smooth peripheral surface cannot be obtained. On the other hand, if the angle α is too small, the peripheral surface of the work piece 3 becomes a completely smooth surface, but this is also not preferable because burrs are generated at the edges of the peripheral surface.

In this apparatus, the shearing side surface 5 of the die 1 is
The clearance between the punch 2 and the movable plate 9 of the punch 2 is about the same as the clearance in the die of a normal punching press, and is 0.
It is suitable to set it to about 01 to 0.1 mm.

The width C of the inclined surface 10 in the direction perpendicular to the moving direction A of the punch 2 is preferably larger than the protrusion width D of the machining allowance 7 of the workpiece 3, and the protrusion width D is 1 It is suitable to be about 2 to 2 times.

The protrusion width D of the machining allowance 7 is the inclined surface 1 of the punch 2.
If it is excessively larger than the width C of 0, the range in which a fracture surface occurs when the machining allowance 7 is cut off tends to be large, which is not preferable.

The protrusion width D of the machining allowance 7 on the workpiece 3 is 1 of the clearance B between the die 1 and the punch 2.
About 0 to 50 times is appropriate. If the protrusion width D of the machining allowance 7 is excessively large, the load applied to the die at the time of cutting off will increase,
If the protrusion width D is too small, burrs are likely to occur due to the deformation of the machining allowance 7 at the time of cutting.

[0022]

In the present invention, the workpiece 3 is placed on the upper surface 4 of the die 1 with the machining allowance 7 protruding from the edge 6, and the punch 2 is moved downward from above. The work material 3 is sheared by the die 1 and the punch 2, and the machining allowance 7
Cut off.

At this time, when the punch 2 is moved downward, the inclined surface 10 of the punch 2 first comes into contact with the machining allowance 7 of the workpiece 3,
As shown in FIG. 2 (a), the machining allowance 7 is bent downward and deformed into a substantially parallelogram shape.

When the punch 2 is further moved downward as it is, as shown in FIG. 2B, the workpiece 3 is sheared by the edge 6 of the die 1 and the edge 11 of the punch 2, and the workpiece 3 is processed. The margin 7 is shifted downward, and a smooth surface 13 is formed on the peripheral surface of the main body portion 12 of the workpiece 3 by shearing.

In a normal punching press, the punch 2
It can be considered that the edge 11 of is a right angle and the machining allowance 7 is not deformed into a parallelogram, but in this case, the shearing progresses to some extent, and the edge between the edge 6 and the edge 11 The material ruptures at once and a fracture surface occurs.

In the present invention, however, breakage unlike in a usual punching press does not occur, and the shearing shifts the machining allowance 7 downward so that the cutting proceeds and the fracture surface does not occur.

The reason why such breakage does not occur in the present invention is not fully understood theoretically, but when the machining allowance 7 is deformed by the inclined surface 10, the machining allowance 7 is used. It is considered that the force acts to press the peripheral surface of the main body portion 12 of No. 3 and the force prevents the occurrence of breakage.

The force pressed against the main body of the work piece 3 due to the deformation of the work piece 7 and the force of the sheared and displaced part of the work piece 7 to separate from the work piece 3 result in the inclined surface 10. It is considered that the smooth surface 12 can be obtained by just balancing when the angle is 30 °.

In the present invention, the punch 2 is further moved downward from the state shown in FIG. 2 (b) so that the punch 2 does not break even if the shearing proceeds further, and a smooth smooth surface 13 is formed on the peripheral surface of the main body portion 12. It is formed.

Then, as the shearing progresses further, and as shown in FIG. 2 (c), when the main body portion 12 of the workpiece 3 and the machining allowance 7 are connected by only a very small portion, For the first time here, a fracture 14 occurs between edges 6 and 11,
The main body portion 12 and the machining allowance 7 are separated.

[0031]

EXAMPLE A die 1 and a punch 2 according to the present invention were manufactured, and a machining allowance 7 formed on a work piece 3 was cut off and finished. The obtained pressed product 15 was as shown in FIG.
A slight fracture surface 16 is formed on the lower edge of the peripheral surface, but the range is small and the thickness of the pressed product 15 is 2
Even in the case of mm, the range E of the fracture surface 16 is 0.1 to 0.3 mm
The degree was large, and most of the rest was occupied by the smooth smooth surface 13 obtained by shearing.

On the other hand, when the machining allowance 7 of the work piece 3 is cut off by the die 1 and the punch 2 having the angle α of 45 °, as shown in FIG. The area E, which is more than half, was occupied by the fracture surface 16, which was almost the same as the peripheral surface obtained by the ordinary punching press.

When the angle α is 15 °,
As shown in FIG. 5, the peripheral surface of the pressed product 15 was entirely occupied by the smooth surface 13, and the fracture surface 16 was not formed.
The burr 17 protruded downward from the lower edge of the peripheral surface and could not be used as it was.

Therefore, in the present invention, the angle α is 3
Only when it is 0 °, an ideal peripheral surface can be obtained in which most of the peripheral surface can be the smooth surface 13 and burrs do not occur, and the error range of the angle α is It should be kept within ± 5 ° at maximum.

[0035]

As described above, according to the present invention, the peripheral surface of the pressed product 15 obtained by cutting off the machining allowance 7 has a very small fracture surface 16 and most of it is a smooth surface 13. ing. Therefore, the appearance is good, and even when the press product 15 is used as a mechanical part, the fracture surface 16 does not become an obstacle and a smooth operation can be obtained.

Further, in the apparatus of the present invention, the clearance B between the die 1 and the punch 2 may be about the same as that of a general punching press, so that the precision of the die is required as compared with the conventional fine blanking. Not.

Further, unlike a shaving process, a complicated die is not required, and it can be carried out as an extension of the ordinary punching press technique, so that it is inexpensive.

Further, the method of the present invention can be implemented at a low cost because the present invention can be introduced as a part of a continuous pressing step and does not require a separate step for finishing.

Further, since the mold is not subjected to excessive load or impact during processing, the life of the mold is extended. Compared with the conventional fine blanking and shaving processes, the mold has about 10 times the durability.

[Brief description of drawings]

FIG. 1 is a central longitudinal sectional view of a main part showing an apparatus of the present invention.

FIG. 2 is a central longitudinal cross-sectional view of a main part showing stepwise a state in which a machining allowance is cut off from a workpiece by the method of the present invention.

3A and 3B show a main part of a pressed product finished according to the present invention, FIG. 3A is a longitudinal sectional view, and FIG. 3B is a front view of a finished peripheral surface.

4A and 4B show a main part of a pressed product finished by a punch in which an angle of an inclined surface is 45 °, FIG. 4A is a longitudinal sectional view, and FIG. 4B is a front view of a finished peripheral surface. .

5A and 5B show a main part of a pressed product finished by a punch in which an angle of an inclined surface is 15 °, FIG. 5A is a longitudinal sectional view, and FIG. 5B is a front view of a finished peripheral surface. .

[Explanation of symbols]

 1 Die 2 Punch 3 Work Material 5 Shear Side 7 Machining Allowance 8 Tip Surface 9 Shear Side 10 Inclined Surface

Claims (4)

[Claims] 1. A die (1) and a punch (2) that slides along the shearing side surface (5) of the die (1), and the tip surface (8) and the shearing side surface of the punch (2). (9)
At the corner of and 30 with respect to the moving direction of the punch (2).
A peripheral surface finishing device for a pressed product, characterized in that an inclined surface (10) having an angle (α) of ± 5 ° is formed. 2. The angle (α) of the inclined surface (10) is 30.
The peripheral surface finishing device for a pressed product according to claim 1, wherein the peripheral surface finishing device is ± 2 °. 3. A work material (3) is placed on a die (1), and a machining allowance (7) of the work material (3) is placed from the upper edge of the shearing side surface (5) of the die (1). The punch (2) having the inclined surface (10) at an angle (α) of 30 ± 5 ° with respect to the sliding direction at the corner between the tip surface (8) and the shearing side surface (9) is projected by Processing allowance (7) for the work material (3)
Surface finishing method for pressed products, characterized by cutting off 4. The width (C) of the inclined surface (10) of the punch (2) in the direction perpendicular to the sliding direction is larger than the protruding width (D) of the machining allowance (7) of the workpiece (3). The peripheral surface finishing method for a pressed product according to claim 3, which is large.