JPH05317987A - Method and device for shearing - Google Patents

Abstract

PURPOSE:To exactly separate a product and a scrap without generating a burr. CONSTITUTION:A material 30 to be cut is set between a punch 16 and a die 6, the material 30 to be cut is cut by the die 6 lowered following to a lowered blank holder 10. The material to be cut is classified into product part 30W and a scrap part 30S at the cut part to form a part having a small sectional area and a stretching die 20 and the blank holder 10 are neared closer and the scrap part 30S is held between them. Then, the die 6 is lowered toward the blank holder 10 and the punch 16 is lowered toward the stretching die 20 when compressing springs 8 and 18 are conpressed. Thus, the scrap part 30S held between the blank holder 10 and the stretching die 20 is applied with a bending stress toward the blank holder 10 side and a tension stress is method on the boundary line between the product part 30W and the scrap part 30S and both parts are flactured to be separated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shearing method and a shearing apparatus for cutting a work material with a shearing tool so as to cut it into a product portion and a chip portion. In particular, the present invention is
The present invention relates to a shearing method and a shearing apparatus capable of shearing an edge of a separated product portion without causing burr.

[0002]

2. Description of the Related Art A shearing process in which a shearing tool is cut into a work material to separate the product from the work material has the advantage that the product and the chips can be separated in one step, and the productivity is extremely higher than that of the cutting process.
However, shearing has a problem in that it is difficult to obtain a flat separation surface as compared with a cut surface. The shape of the separation surface of the product obtained by the conventional shearing method is shown in FIG. In FIG. 5, the shearing tool is cut from the bottom to the top of the drawing. As shown in FIG. 5, the separating surface of the sheared product 50 is constituted by a burr 52, a fracture surface 54, a shear surface 56, and a drool 58.
Of these, the burr 52 is caused by the occurrence of cracks at the time of fracture from the fracture surface side. Due to the burr 52, the edge of the sheared product 50 becomes a sharp edged tool, which is not only dangerous when handled, but also the fitting between the parts is deteriorated, and the coating film is thin only on the burr 52. As a result, various adverse effects such as deterioration of corrosion resistance are caused.
In particular, in the case of electronic parts or the like, the burr 52 that has fallen off during use comes into contact with an electronic circuit, causing a problem such as insulation failure or a short circuit.

Therefore, in order to prevent such a problem, various techniques have been developed as a shearing method that does not cause burr, and typical methods include a vertical punching method and a flat pressing method. As shown in FIG. 7, the upper and lower punching method is performed on the workpiece 80 in the first step by punching the punch 72 and the die 7
6 and half-sheared (Fig. 7 (A)), followed by the second
In the process, the reverse presser 78 is moved toward the plate presser 74 (FIG. 7 (B)). As a result, the final separation is performed while restoring the shear deformation of the workpiece 80. As shown in FIG. 7C, the product 80W thus obtained is said to have no burrs due to the sags 82A and 82B formed at the upper and lower ends of the separation surface. However, actually, as a result of the smooth surface 84B generated in the first step being rubbed by the protruding portion of chips (not shown) corresponding to the fracture surface 86 in the second step, a burr may be generated in the portion of the droop 82B. Many.

The flat pressing method shown in FIG. 6 has been developed in order to solve the problems of the upper and lower punching methods. In this flattening method, the work piece 60 half-sheared in the first step is set in the flattening die 64 as shown in FIG. 6 (A). And
As shown in FIG. 6B, this is a method of separating the products by pushing back the workpiece 60 in the semi-sheared state by the upper plane die 66 and the lower plane die 68. In this flat pressing method, in the first step, as shown in FIG. 6 (A), shearing is performed with a negative clearance 60c, thereby eliminating the problem of scraping due to chips in the vertical punching method. ..

[0005]

However, in such a flat pressing method, depending on the material of the material to be processed and the processing conditions of the first step, the material 60 to be semi-sheared by the flat pressing die 64 is used. There was a problem that the products could not be separated by pushing back. In particular, for ultra-thin plate materials used for electronic parts and the like, it is extremely difficult to reliably separate products without causing burr by shearing in the conventional techniques such as the vertical punching method or the flat pressing method. It was difficult. Therefore, it is an object of the present invention to provide a shearing method and a shearing apparatus capable of reliably separating a product and chips without causing a burr on the product.

[0006]

[Means for Solving the Problems] Therefore, claim 1 of the present application
In the invention according to, in order to solve the above problems, there is provided a processing method of separating a work material into a product portion and a chip portion by shearing, wherein the work material is interposed between a pair of shearing tools that are offset from each other. A step of sandwiching a work material, further cutting the pair of shearing tools to a depth at which a crack does not occur on the product part side of the work material, and the chip part of the cut work material, A step of applying tensile stress between the chip portion and the product portion to separate them while bending the portion cut by the pair of shearing tools toward the cut side with respect to the center. Created a shearing method that

Further, in the invention according to claim 2 of the present application, there is provided a processing device which separates a material to be processed into a product portion and a chip portion by shearing, and is an overhang provided so as to face each other and can be separated from each other. A die and a plate retainer, a punch having a projection having the shape of the product portion, slidably fitted to the overhanging die and always moving integrally with the overhanging die, and the shape of the product portion A die that has a slanting portion that projects in a ring shape along with, is slidably fitted to the plate retainer, and that is always moved integrally with the plate retainer, and the die and the punch are close to each other. A direction in which the work material is cut, and after the chip portion of the work material is sandwiched between the overhanging die and the plate retainer, the die approaches the overhanging die with respect to the plate retainer. The punch with sliding has created a shearing device, characterized in that it comprises a sliding means for sliding in a direction away from the plate retainer relative to said flared die.

[0008]

In the shearing method according to the first aspect of the present invention having the above structure, the work piece is separated into the product portion and the chip portion as follows. First, the material to be processed is sandwiched between a pair of shearing tools that are offset from each other, and then the shearing tool is cut to a depth that does not cause cracks on the product side. As a result, the material to be processed is divided into a product portion and a chip portion at the cut portion, and a portion having a small cross-sectional area is formed at the boundary portion between the two. Next, the chip portion of the work material is bent toward the cut side with the cut portion as the center. At the same time, a tensile stress is applied between the chip part thus bent and the product part. Here, since a portion having a small cross-sectional area is formed by being cut at the boundary between the product portion and the chip portion, the tensile stress concentrates on this portion and the two are separated by constriction breakage. As a result, a dripping accompanying the cut occurs on the cut surface of the product portion on the cut side. On the opposite side, dripping due to pulling occurs. Therefore, the work piece is separated into the product portion and the chip portion without causing burr on the separation surface of the product portion. In this way, the shearing process ensures that the products can be separated without causing burr on the product parts.

Further, the shearing of the material to be processed by the shearing device according to the second aspect is performed as follows.
First, a punch having a projecting portion having the shape of the product portion and a die having an inclined portion projecting annularly along the shape of the product portion are provided between the overhanging die and the plate retainer which are provided so as to face each other and can be spaced apart from each other. In the meantime, the work material is set.
Next, the overhanging die and the plate retainer move relatively to approach each other, and the punch and the die also move toward each other accordingly. Then, the workpiece is cut by the depth of the recessed portion of the inclined die. As a result, the material to be processed is divided into a product portion and a chip portion at the cut portion, and a portion having a small cross-sectional area is formed at the boundary portion between the two. Since the depth of the recess of the inclined die is adjusted to a depth that does not cause cracks on the product portion side, cracks that are a source of burrs do not occur at the product portion at this stage.

Then, the overhanging die and the plate retainer are brought closer to each other, and the chip portion of the workpiece is sandwiched between them. After that, the slide means is actuated so that the die is slid in the direction approaching the overhanging die with respect to the plate retainer, and the punch is slid in the direction away from the plate retainer with respect to the overhanging die. As a result, bending stress to the plate pressing side is applied to the chip part sandwiched between the overhanging die and the plate retainer, and tensile stress is applied between this chip part and the product part sandwiched between the punch and die. Be done. Here, since the boundary between the product portion and the chip portion is cut to form a portion having a small cross-sectional area, tensile stress concentrates and this portion is constricted and fractured. This separates the two. In this way, the shearing process ensures that the products can be separated without causing burr on the product parts. Further, according to the shearing device of the present invention, such shearing can be performed by one device and by only one step of bringing the overhanging die and the plate retainer close to each other.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment embodying the present invention will be described with reference to FIGS. First, the overall configuration of the shearing device will be described with reference to FIG. FIG. 1 is a diagram showing an overall configuration of a shearing device of this embodiment, and reference numeral 1 is a shearing device. This shearing device 1 includes a die 6 with inclination, a plate retainer 10, a punch 16,
The overhanging die 20 is mainly configured. A pair of guide posts 1 are provided on the upper surface of the overhanging die 20.
4A and 14B are fixed, and this guide post 14
The plate retainer 10 is slidably fitted to A and 14B via slide portions 12A and 12B. As a result, the plate retainer 10 and the overhanging die 20 can approach and separate from each other.

The plate retainer 10 is provided with a through hole 10a having a varying inner diameter, and the inclined die 6 is slidably fitted in the through hole 10a. However, as shown in FIG. 1, the large-diameter portion of the inclined die 6 abuts on the stepped portion of the through hole 10a, so that the upward movement of the inclined die 6 with respect to the plate retainer 10 is limited. The upper pressure plate 4 is screwed and fixed to the upper end surface of the inclined die 6 by a fixing bolt 2. A compression coil spring 8 is fitted and inserted between the upper pressure plate 4 and the plate retainer 10.

On the other hand, the overhanging die 20 has a through hole 20.
a is provided, and the punch 1 is provided in the through hole 20a.
6 is slidably fitted. Then, as shown in FIG. 1, the flange portion of the punch 16 contacts the through hole 20a, so that the punch die 2 for the punch 16 is extended.
The rise above 0 is limited. Overhanging dice 20
A lower pressure plate 24 is provided on the lower end surface of the pair of fixing bolts 22.
It is screwed and fixed by A and 22B. A compression coil spring 18 is fitted between the lower pressure plate 24 and the flange portion of the punch 16.

Here, the compression coil springs 8 and 18 are
A spring whose deformation limit pressure is greater than or equal to the shearing force of the workpiece is used, and an initial displacement corresponding to the shearing force of the workpiece is applied. As a result, as will be described later, the upper pressing plate 4 is pushed and the inclined die 6 is lowered, so that the workpiece is cut without compressing the compression coil springs 8 and 18, and the cut amount is inclined. The compression coil springs 8 and 18 are compressed at the same time when the depth of the die recess is reached.

Next, the structure of the processed portion of the inclined die 6 and punch 16 will be described with reference to FIG. FIG. 2 shows the lower end of the inclined die 6 and the plate retainer 1.
It is an expanded sectional view which shows the upper end part of 0. Sloped dice 6
As shown in FIG. 2, a concave portion 6b having a depth of 6h is provided on the lower end surface of the concave portion 6b, and the periphery of the concave portion 6b is a conical surface having an inclination angle θ. The shape of the recess 6b is made according to the product shape, and the depth 6h of the recess 6b is
The depth is such that no cracks occur when the inclined die 6 is cut into the workpiece. On the other hand, the upper end portion of the punch 16 has a shape in which a central portion 16a projects as shown in FIG. .. And
Projection height of the punch 16 from the upper surface of the punch die 20 when the punch 16 and the punch die 20 are in the original position 1
6h corresponds to the depth 6h of the recess 6b.

1 to 5 for the procedure of the shearing process using the shearing device 1 having the above configuration.
Will be described with reference to. First, the inclined die 6, the plate retainer 10, the punch 16, and the overhanging die 20 are set to the original position. As shown in FIGS. 2 and 4 (1),
In the original position, the height of the tip of the inclined die 6 matches the lower surface of the plate retainer 10. Further, as described above, the protrusion height 16 of the punch 16 from the upper surface of the overhanging die 20 is increased.
h corresponds to the depth 6h of the recess 6b. The shearing device 1 set in this way is installed in the upper and lower dies of a single-acting press device (not shown). Then, a thin plate-shaped workpiece 30 as shown in FIG. 4 (2B) is formed as shown in FIG. 4 (2A).
Then, the punch 16 is placed on the punch 16 as shown in FIG. As a result, FIG.
The upper pressurizing plate 4 shown in FIG. 2 is pushed down by the upper die of the single-acting type press device, and the inclined die 6 and the plate retainer 10 are integrally lowered.

Then, the lower end of the inclined die 6 comes into contact with the workpiece 30 (FIG. 4 (2A)), and further descends, so that the concave die 6b of the inclined die 6 has a depth 6h. 30 is cut (FIG. 4 (3A)). As a result, as shown in FIG. 4 (3B), the work material 30 is divided into the product portion 30W and the chip portion 30S in the cut portion, and a portion having a small cross-sectional area is formed at the boundary portion between the both. To be done. As mentioned above, depth 6h
Has a depth that does not cause a crack when the inclined die 6 is cut into the workpiece 30, so that a crack which is a source of burr does not occur in the product portion 30W at this stage. Further, the protrusion height 16h of the punch 16 is equal to the recess 6
Since the depth 6h of b corresponds to the depth of 6h, when the inclined die 6 cuts into the work piece 30 by a depth of 6h, the work piece 30 is simultaneously cut by the plate holder 10 and the overhanging die 20.
The chip portion 30S is sandwiched (FIG. 4 (3A)).

In this state, the upper pressurizing plate 4 is further pushed down by the upper die of the single-acting type press device so that the shearing force of the work material 30 which is the deformation limit pressure against the compression coil springs 8 and 18 is more than the shearing force. Power is added. As a result, the compression coil springs 8 and 18 start to deform, and as the upper die of the single-acting press machine descends, the inclined die 6 presses the plate holder 1
Slide down to 0. The punch 16 is also pushed by the inclined die 6 and slides downward with respect to the overhanging die 20. As a result, the product portion 30W held between the inclined die 6 and the punch 16 and the plate retainer 1
0 and the chip portion 30 sandwiched between the overhanging die 20
Tensile stress due to bending is applied between S and S (Fig. 4 (4
A), (4B)). Here, since the boundary between the product portion 30W and the chip portion 30S is cut to form a portion having a small cross-sectional area, tensile stress concentrates, and this portion is constricted and fractured, so that they are separated from each other. (FIG. 4 (5A), (5B)).

As described above, by using the shearing device 1 of this embodiment, as shown in FIGS. 3 and 4 (5B), the product portion 30W does not have a burr and is surely produced. It is possible to separate 30W and the chip portion 30S. Further, according to the shearing device 1 of the present embodiment, the shearing process can be performed by a single device and by only one step of bringing the overhanging die and the plate retainer close to each other. Therefore, as the pressurizing mechanism, a simple pressurizing device such as the single-acting press device can be used as described above.

In the above embodiments, the length and thickness of the inclined die 6 and the punch 16 and the shape of each tip portion are merely examples, and other various sizes and shapes can be used. Further, in the present embodiment, the compression coil spring is used as the slide means for sliding the die and the punch with respect to the plate retainer and the overhanging die at a predetermined stage, but other mechanisms may be used. The structure, shape, size, material, number, arrangement, etc. of the other parts of the shearing device are not limited to those in this embodiment.

Further, as an effect peculiar to this embodiment, since the compression coil spring is used as the slide means for sliding the die and the punch with respect to the plate retainer and the overhanging die at a predetermined stage, the shearing device 1 is added. The desired effect can be obtained by one step of continuously compressing by the pressure mechanism. Further, by providing the conical surface in the cut portion at the tip of the die, there is an advantage that tensile stress is applied more effectively.

[0022]

According to the present invention, a step of cutting a shearing tool to a depth such that a crack does not occur on the side of a product portion of a work material, and a pulling while applying a bending stress between the product portion and the chip portion. Since a shearing method having a step of applying a stress to separate the product is created, the product and the chips can be reliably separated without causing burr in the product. This makes it possible to obtain a non-burr processed product by highly productive shearing, which is a very practical shearing method.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of a shearing device of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a die and a punch of the shearing device.

FIG. 3 is a diagram showing separation of a product and chips by the shearing method of the present invention.

FIG. 4 is an explanatory diagram showing a procedure of an embodiment of a shearing method.

FIG. 5 is a diagram showing a conventional sheared product.

FIG. 6 is an explanatory diagram showing an example of a conventional shearing method.

FIG. 7 is an explanatory diagram showing another example of a conventional shearing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shearing device 6 Dies 8, 18 Sliding means 10 Plate retainer 16 Punch 20 Overhanging die 30 Work material 30W Product part 30S Chip part

Claims (2)

[Claims] 1. A processing method for separating a work material by shearing into a product portion and a chip portion, wherein the work material is sandwiched between a pair of shearing tools that are offset from each other and face each other. A step of cutting the shearing tool to a depth that does not cause a crack on the side of the product part of the work material, and the chip part of the cut work material is cut by the pair of shearing tools. A step of applying tensile stress between the chip portion and the product portion while bending toward the side that is cut centering on a point and separating,
And a shearing method. 2. A processing device for separating a work material into a product portion and a chip portion by shearing, wherein an overhanging die and a plate retainer which are provided so as to face each other and can be separated from each other, and a shape of the product portion are provided. A punch that has a protruding portion that is slidably fitted to the overhanging die and always moves integrally with the overhanging die; and an inclined portion that annularly protrudes along the shape of the product portion. A die that is slidably fitted to the plate retainer and always moves integrally with the plate retainer; and the die and the punch are brought close to each other to cut the workpiece, and the overhanging die is provided. After the chip portion of the work material is sandwiched between the plate retainers, the die is slid relative to the plate retainer in a direction approaching the overhanging die, and the punch is set to Sliding means for sliding in a direction away from said plate presser against die out, shearing apparatus characterized by having a city.