JPH01246094A - Round blade tool for cutting - Google Patents

Abstract

PURPOSE:To make it possible to obtain a web of a desired side edge surface configuration by chamfering the tip of at least one of an upper blade and a lower blade to get apart from the other blade out in the diametric direction gradually. CONSTITUTION:For a pair of round blades of an upper blade and a lower blade, the tip of the upper blade 11 is chamfered to get apart from the lower blade out in the diametric direction gradually. By this chamfering, a gap is produced between the tip of the upper blade and the lower blade, and this gap is gradually reduced as a web to be cut is cut from the tip part. The cut surface of the web 20 is formed having irregularities along the thickness of the web, and the deepness of the irregularities change corresponding to the configuration of chamfering. By setting the configuration of chanfering properly, therefore, both edge surfaces of the web can be formed protruding to be outer than applied layers of emulsion 20B or magnetic material on the surface, thereby occurrence of a failure of a camera or the like by peeling off of the emulsion inside the camera can thus be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a tool for continuously cutting webs such as plastic films, and more particularly to a cutting round blade tool consisting of two rotating round blades. It is something.

(Prior art) For example, photographic roll films and magnetic tapes are generally
After undergoing various treatments and processing while still being wider than the width of the product, it is finally cut to the width of the product.

Conventionally, as a tool for continuously cutting raw webs such as films and magnetic tapes in the longitudinal direction, an upper blade and a lower blade, both of which are round blades, are arranged so that the parts near the cutting edges overlap each other. A widely used tool is to cut the web by rotating the two blades and feeding the web between the two blades approximately parallel to the axis of rotation of the blades. In the conventional round cutting tool with the above configuration, the upper and lower blades have cutting edge shapes as shown in Fig. 8 with numbers 50 and 51, respectively, or as shown in Figs. 9 and 10. It was said to have a cutting edge shape. That is, in conventional cutting tools with round blades, the cutting edges of the upper and lower blades are at right angles, or have a sharp shape that cuts toward the opposing blade. Regarding this type of round blade, for example, Utility Model Publication No. 53-117 [18
5 and 51-117887.

(Problem to be Solved by the Invention) Photographic roll films are cut in the manner described above after an emulsion is coated on the surface of a support made of a plastic web. The shape of both ends of the film cut with the round cutting tool is as shown in FIG. 11, for example. This first
In Figure 1, 60 is a support and 81 is an emulsion.

When the film is cut into such a shape, the support 60 protrudes outward from the emulsion 61 on one side of the film, and vice versa on the other side. In this way, when the emulsion 61 protrudes outward from the support 60,
For example, when film is fed through a camera, the sides of the emulsion may rub against parts inside the camera, causing the emulsion to flake off into powder inside the camera. This flaked powdery emulsion adheres to the film surface, degrading image quality or causing camera failure. Similar failures can occur not only in cameras but also in production equipment and processing machines.

Such defects are often particularly noticeable in motion picture films.

I have described the problems with photographic film above, but
In the case of other magnetic tapes, if the support is cut so that the magnetic material coated on the web-like support protrudes outward from the support, powder of the magnetic material may be deposited on video cameras, etc. It may peel off inside. Therefore,
When cutting a product having a coating layer on a support web, it has been desired to prevent the coating layer from protruding to both side edges of the web.

The above-mentioned problem can be solved if photographic film, magnetic tape, etc. can be cut into a state in which the support protrudes outward from the coating layer at both ends thereof. SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a cutting tool with a round blade that can cut a web made of plastic or the like into a desired cutting surface shape.

(Means for Solving the Problem) The round cutting tool of the present invention is comprised of an upper blade and a lower cutting blade that are rotated round blades as described above. The cutting edge of at least one of the blade and the lower blade is chamfered with nine chamfers so as to gradually move away from the other blade toward the radial outside.

(Function) If the cutting edge of the upper or lower blade, or both, is chamfered as described above, a gap will be created between the cutting edge and the opposing blade, and this gap will cause the web to It becomes gradually narrower as it is cut in from.

Therefore, the cut surface of the web has irregularities throughout the thickness direction of the web, and the amount of the irregularities changes depending on the shape of the chamfer. Therefore, by appropriately setting the shape of the chamfer, both end surfaces of the web can be made to protrude outward beyond the coating layer of emulsion, magnetic material, etc. on the surface thereof.

(Example) Hereinafter, the present invention will be described in detail based on an example shown in the drawings.

3 and 4 show a round cutting tool according to an embodiment of the present invention. The annular lower blade 10 is fixed to a lower blade shaft 15 that is rotated by a drive device (not shown). Similarly, the annular upper blade 11 is fixed to an upper blade shaft 14 that rotates in conjunction with the lower blade shaft 15. The upper blade 11 is held by an upper blade holder 13 fixed to an upper blade shaft 14, and is pressed by a holder cap 16 fitted to the upper blade holder 13 via a buffering annular spring 12. , is fixed to the upper blade shaft 14. The lower blade ■0 and the upper blade 11 are arranged so that their cutting edges overlap each other, and each has a fourth blade.
Rotated in the direction of the arrow in the figure. The web-like film 20 is fed between the two blades 10.11 in a state substantially parallel to the lower blade rotation axis 10C and the upper blade rotation axis IIC, and is continuously cut in the longitudinal direction thereof.

Here, in this device, as shown in FIG.
The cutting edge of the upper blade 11 is at a right angle, but the cutting edge of the upper blade 11 is chamfered so as to gradually move away from the lower blade 10 toward the radial outside. Because of this chamfering, at the position where the film 20 starts to enter between the two blades 10.11 (biting point), there is a gap between the two blades 10.11 as shown in FIG. As shown in Figure 2, at the position between the rotating shafts 1OC and 111C (axis center point), the double-edged blade 10
．． 11 are in contact with each other. Therefore, by appropriately setting the shape of the chamfer described above, the cut shape of the side cross section of the film 20 can be made as shown in FIG. 5. This point will be explained in detail below.

The cut surface on the right side of the film 20 in FIG. 5 remains on the lower blade 10 when it is cut by the lower blade lO and the upper blade 11, so this is referred to as the lower blade side cut surface 20S, and -
Since the cut surface on the universal side is pressed down by the upper blade 11, this will be referred to as the upper blade side cut surface 20U, and the amount of unevenness of both cut surfaces 208 and 200 will be considered.

As shown in FIG. 5, the cut position of the upper surface of the support 20A of the film 20 is designated as D, and the average protrusion amount A1 of the upper half of the support 20A and the average protrusion of the lower half relative to this position It was investigated how ff1B changes by changing the chamfer shape. In this example, the height T of the chamfer (see FIG. 1) was kept constant at approximately 100 μm, and the protrusion amounts A and B were examined by varying the width W of the chamfer. The results are shown in FIG. 6 for the lower blade side cutting surface 205 and in FIG. 7 for the upper blade side cutting surface 20U. Note that the protrusion amount = (minus) indicates that the cut surface position is recessed inward from the cut position. Also, in this case, the meshing j1M of the double-edged blade 1O111 (second
(see figure) is approximately 1 mm.

As can be seen from FIG. 6, by changing the chamfer width W, the lower blade side cut surface 20S can be made to protrude from the cut position of the lower half of the support, or can be recessed (upper half side is always protruding). As can be seen from FIG. 7, the same applies to the upper blade side cutting surface 20U. If the chamfer width W is approximately 20 μm or more, the lower half side of the upper blade side cut surface 20U protrudes outward from the cut position, and at this time, the upper half side of the lower blade side cut surface 20S is also at the cut position. Since it protrudes further outward, the support body 20A
The film 20 can be cut in such a state that the left and right end faces of the emulsion 20B protrude outward from the end faces of the emulsion 20B (which are located at approximately the same position as the cut position).

In the embodiment described above, only the upper blade 11 is chamfered, but even if only the lower blade 10 is chamfered as shown in FIG. 12, the upper blade 11 may be chamfered as shown in FIG. Both the lower blade 10 and the lower blade 10 may be chamfered. Even in such a case, by changing the shape of each chamfer, the shape of the cut surface of the web can be made into a desired shape.

Further, the round blade cutting tool of the embodiment described above is formed for cutting photographic film, but the round blade cutting tool of the present invention can also be used for other purposes such as the above-mentioned magnetic tape offset printing plate, Of course, it is also possible to cut an original web having a coating layer on a web support such as photographic paper. Furthermore, the apparatus of the above embodiments is used to obtain a cut surface in which both end surfaces of the film support protrude laterally and outwardly than the emulsion, but according to the apparatus of the present invention, such a It is also possible to obtain a cutting surface other than the one shown in FIG. That is, as shown in FIGS. 6 and 7, for example, the shape of the cutting surface can be arbitrarily cut by changing the chamfer shape of the upper blade or the lower blade, so the shape of the chamfer can be appropriately set according to the desired cutting surface. do it.

(Effects of the Invention) As explained in detail above, the round cutting tool of the present invention has chamfered edges of the upper blade, the lower blade, or both of them, and the shape of the cutting surface can be varied depending on the shape of the chamfer. Since this tool can be changed, a web with a desired side end shape can be obtained at will. If this cutting round blade tool is used especially for cutting the aforementioned photographic film, it is possible to form a film in which both end surfaces of the support protrude laterally and outwardly than the emulsion. It is possible to solve problems such as the emulsion peeling off and causing damage to cameras and the like.

[Brief explanation of the drawing]

FIGS. 1 and 2 are cross-sectional views showing the positional relationship between the upper and lower blades at the film biting point and the shaft center point of a cutting round blade tool according to an embodiment of the present invention, and FIG. 3 and FIG. FIG. 4 is a partially cutaway elevation view and side view showing the round cutting tool of the above embodiment, respectively, and FIG. 5 is a cut surface of a photographic film cut by the round cutting tool of the above embodiment. 6 and 7 are graphs showing the relationship between the cutting edge chamfer width and the amount of unevenness on the cut surface of the film of the cutting round cutting tool of the present invention. FIG. 11 is a schematic diagram showing the shape of the cutting surface of a web by a conventional round cutting tool, and FIG. 12 and FIG. FIG. 7 is a cross-sectional view showing another example of the shape of the cutting edge of the round-blade tool.

Claims (1)

[Scope of Claims] An upper blade and a lower blade, both of which are round blades, are rotated with their respective portions near the cutting edges overlapping each other, and the rotation axis of the blade is located between the upper blade and the lower blade. In a cutting round cutting tool that continuously cuts a web that is fed approximately parallel to the cutting edge, the cutting edge of at least one of the upper blade and the lower blade is chamfered so as to gradually move away from the other blade toward the radial outside. A round blade tool for cutting.