JPH0418968B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a multi-slitting device for metal strips.

More specifically, the present invention eliminates so-called slit distortion, a phenomenon in which residual stress formed at the slit edges of a metal strip processed with multiple slits deteriorates the dimensional accuracy of products made from the strip. This invention relates to a multi-slitting device.

BACKGROUND ART The above-mentioned problem of slit distortion will be explained with reference to the attached drawings.

As shown in the attached Figure 2A, a wide coiled metal strip material 1 is slit into multiple narrow strips 2,
As shown in FIG. 2B, a product 3 including an edge 2' of a strip 2 is manufactured by press punching or the like. At this time, the slit edge 3' of the product 3 shown in FIG.
becomes uneven. In particular, the width w of the product portion including the slit edge 3' shown in Fig. 2C is small;
In addition, when the length ll is large, the degree of flatness failure becomes significant. This phenomenon is known as slit distortion.

This slit distortion is measured from the edge 2' of the strip after slitting, at most 2 to 200 mm thick, as shown by diagonal lines in Figure 3.
It disappears when the region 4, which is three times the width, is removed by cutting, etching, or other methods.

Slit distortion is formed by slit processing using a rotating blade, which is the most commonly used method. The slitters generally used for this type of slitting process are
As shown in the figure, a plurality of rotary blades 7, according to a predetermined slit width and number of slits, are mounted on upper and lower arbor shafts 6, 6' whose both ends are rotatably supported by stands 5, 5'.
This is a so-called gangster slitter 8 in which 7' is arranged.

FIG. 5 is a front view showing the positional relationship between two upper and lower rotary blades 7, 7' which cut into strips having a width w. Horizontal gap (clearance) between the upper and lower rotating blades
δ is normally set to 0.05 to 0.15t (t: strip thickness).
When viewed in the vertical direction, in the case of a slit in a band plate, the upper and lower rotary blades are set in a slightly overlapping state, as shown in FIG. The amount of overlap L varies depending on the thickness and material of the strip, and the state of wear of the rotary blade, but it is basically set to a small value within the range that allows cutting.

Next, the deformation of the material during slitting with a rotary blade will be explained. Slit line c- shown in Figure 6
c, the positional relationship between the material and the upper and lower rotary blades 7, 7' is as shown in FIG. The material strip 1 advancing from the left reaches a position a-a where the vertical interval α of the circumference of the upper and lower rotary blades 7, 7' is equal to the strip thickness t.
It gets caught in the rotating blade. Shearing begins from here, and cutting down by the upper rotating blade 7 and cutting up by the lower rotating blade 7' proceed simultaneously, and in many cases,
By the time it reaches position b-b where α=0, a break occurs and it is separated into a strip 2B cut down by the upper rotary blade 7 and a strip 2A cut up by the lower rotary cutter 7'. That is, on the slit line c-c in FIG. 6, the direction in the height direction in which the material travels suddenly changes at the biting position a-a,
Between the distance g between the position connecting the center O-O' of the upper and lower rotary blades, there is a height difference h between the strips 2A and 2B as shown by the formula below.

h=L+t/2 (L: overlap, t: strip thickness) By the way, the phenomenon in which the height difference of h from the biting position is seen only at the slit line c-c in Figure 6, and the strip width from the rotary blade to Lines separated in the direction, such as the line c′-c′ or c″- in FIG.
The c'' line shows only a gradual change as shown in FIG.

Therefore, in the width direction cross section passing through the biting position a-a, the material is warped vertically alternately as shown in FIG. 9. Of course, this warping is facilitated by the bending of the material due to the bending moment M during shearing as shown in FIG.

In the end, regarding the strip 2A shown in Fig. 7,
The cross-sectional shapes of the slitter entry side in the c-c cross section and the c'-c' cross section are as shown in FIG. The cross-sectional shape of the entrance side is as shown in Figure 11B.

Obviously, the line length of the c-c cross section is longer than the line lengths of c'-c' and c''-c'', and when viewed in the width direction of the strip, only the material on the slit line is undergoing tensile deformation in the threading direction. It is processed into slits.

However, if we look at the strip material after slitting, the edge c-c and the central part c゜-c' or c''-
c'' have the same length, and it is impossible for only edge c-c to become longer.In other words, as shown in Figure 12, compressive residual stress is formed on the slit edge, and in order to balance this, Small tensile residual stress occurs in areas other than the edges.This residual stress has little effect on the shape of the strip when it is in its original state, but in the case of a product like the one shown in Figure 2 C above, The compressive residual stress is released by twisting the slit edge.The conventional practice of minimizing the overlap between the upper and lower rotary blades mentioned above has resulted in the reduction of the line length difference as shown in Figure 11. This also has the effect of lowering the residual stress level of the slit edge.

However, in order to completely eliminate the wire length difference, it is necessary to set g=0 as shown in FIG. 7, which makes it impossible to perform slitting. Therefore, as a practical measure against slit distortion, a method is adopted in which the slitted strip is repeatedly bent using a leveler to reduce the residual stress at the slit edge.

However, with this method, it is only possible to confirm whether the residual stress has decreased below the limit value after punching the product, and if it is insufficient, leveling processing must be performed again, making the process complicated.
Furthermore, since cold working with a leveler is added, it cannot be applied at all to products where work hardening would be harmful.

Problems to be Solved by the Invention The present invention aims to solve the problems of the prior art described above.

That is, an object of the present invention is to provide a novel slitting device that does not form residual stress on the slit edge while the slit remains in place.

Means for Solving the Problems The present invention is a longitudinal multi-line slitting device for a metal strip that is provided with a plurality of upper blades and lower blades provided in parallel at predetermined intervals, the upper blades or one of the lower blades is a rotating blade, and the other is a straight fixed blade with a horizontal plane between at least the biting position of the metal strip and the position where cutting is completed;
The rotary blade is arranged between straight fixed blades having opposing blades, and the mounting positions of the straight fixed blade and the rotary blade are adjusted relative to the metal strip to be cut by running on the surface of the straight fixed blade. This is a multi-strip slitting device for a metal strip, characterized in that the edges of the strips are fixed and run on the linear fixed blade without forming any residual stress.

Hereinafter, the present invention will be explained by way of examples and with reference to the accompanying drawings. It goes without saying that these examples are merely illustrative of the present invention and do not limit the technical scope of the present invention.

Embodiment FIG. 1 is a schematic diagram of a slittor of the present invention,
Particularly, FIG. 1A shows the A-type device, and FIG. 1B shows the B-type device. These FIGS. 1 particularly shows the positional relationship between the workpiece material, the upper blade, and the lower blade, and the threading state.

The A-type slitter shown in Fig. 1A has an upper rotary blade 7.
and a fixed lower straight blade 9'.

The upper surface of the lower straight blade 9' is from a point P on the entry side of the biting position a-a to at least a point Q where cutting is completed.
The section up to this point is horizontal. Therefore, the lower straight blade 9'
The slit line C-C of the strip 2A placed on top becomes horizontal, and no difference in line length between the center and edge portions of the strip as shown in FIG. 11A occurs, and as a result, no residual stress is formed.

Note that the moment (first
In order to prevent warping due to the following (see Figure 0), a presser roll 10 is used at the biting position a-a. The pressing roll 10 presses the material strip 1 against the upper surface of the lower straight blade 9', for example, by means of a pressure cylinder 12 via an arm 11.

On the other hand, to explain the strip 2B cut down by the upper rotary blade 7, the slit line C-C is suddenly pushed down at the biting position, causing width warping, and eventually the material strip 1 at the biting position a-a.
The cross section in the width direction has a shape as shown in FIG. 13A, and residual stress is formed in the strip 2B.

Therefore, in the case of method A, the strip 2B should be used for applications where slit distortion is not a problem, or the width of the strip 2B should be increased by changing the width of the upper rotary blade 7 as shown in FIG.
It will be reduced to a thickness of about

On the other hand, the B-type slitter shown in FIG.

In this case, the slit line of the strip 2B passing directly under the upper straight blade 9 becomes horizontal, and no residual stress is formed. The strip 2 cut up by the lower rotating blade 7'
A shows the biting position a of the slit line C-C.
- Residual stress is formed due to the warping of the width due to the sudden push-up at -a, so it is used in applications where slit distortion is not a problem, or the width of the strip 2A is reduced to about the thickness of the lower rotary blade 7'. It will be disposed of.

Effects of the Invention As described above, the present invention is based on the novel idea of using a slitter that combines a rotating blade and a straight blade to prevent residual stress from being generated in the strip where the plate surface is in contact with the straight blade.

The strips slit by the method of the present invention have no slit distortion, do not require leveling processing,
It can be used as is for press processing, etc.

[Brief explanation of drawings]

FIGS. 1A and 1B are schematic diagrams of embodiments of the slitter of the present invention, and FIG. 2 is an explanatory diagram of slit distortion occurring in strips obtained by slitting a wide material strip.
Figure 3 is an explanatory diagram of the width of the residual stress generation area of the slit edge, Figure 4 is a configuration diagram of the gang slit, and Figure 5
The figure is an explanatory diagram of the setting of the upper and lower rotary blades, Fig. 6 is an explanatory diagram of the widthwise position of the strip plate, and Fig. 7 is a side view showing changes in the slit line in a conventional slitter.
Fig. 8 is an explanatory diagram of the longitudinal side shape of the widthwise portion other than the slit line, Fig. 9 is an explanatory diagram of the width warping of the strip at the biting position, and Fig. 10 is an explanatory diagram of the bending due to the moment during shearing. , 11th
The figure is an explanatory diagram of the difference in side shape depending on the position in the width direction on the entrance side of the sliver and the resulting difference in line length.
Figure 2 is an explanatory diagram of the residual stress formed in the strip after slitting, and Figures 13A and 13B are diagrams showing the structure of the present invention shown in Figure 1A with different distances between the upper rotary blade and the lower straight fixed blade. FIG. 3 is a cross-sectional view in the width direction at the biting position of the slit. Main reference numbers, 1: Metal strip material, 2, 2A,
2B: strip material, 2': edge of strip material, 3s product,
3': Slit edge, 5,5': Stand, 6:
Upper arbor shaft 6, 6': Lower arbor shaft, 7: Upper rotating blade, 7': Lower rotating blade, 9: Upper straight fixed blade, 9':
Lower straight fixed blade, 10: Presser roll, 11: Arm, O: Center of rotation of upper rotating blade, O': Center of rotation of lower rotating blade.

Claims (1)

[Claims] 1. A longitudinal multi-slitting device for a metal strip, which is equipped with a plurality of upper blades and lower blades arranged in parallel at predetermined intervals, wherein either the upper blade or the lower blade is a rotary blade. and the other is a linear fixed blade whose horizontal plane is at least between the biting position of the metal strip and the position where the cutting is completed, and the rotary blade is arranged between the linear fixed blades with opposing blades,
The installation positions of the linear fixed blade and the rotary blade are fixed with respect to the metal strip that is cut by running on the surface of the linear fixed blade, and residual stress is applied to the edge of the strip running on the linear fixed blade. A multi-slit processing device for a metal strip, characterized in that it does not form.