JPH0767675B2 - Round blade tool for cutting - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a tool for continuously cutting a web such as a plastic film, and more particularly to a cutting circular blade tool composed of two rotating circular blades. It is a thing.

(Prior Art) For example, photographic roll films and magnetic tapes are generally
After being subjected to various kinds of processing and processing while being wider than the width of the product, it is finally cut into the width of the product.

As a tool for continuously cutting a raw web such as a film or a magnetic tape in the longitudinal direction thereof, conventionally, an upper blade and a lower blade, both of which are round blades, are arranged so that the portions near the respective cutting edges overlap each other. A tool is widely used in which the web is rotated between them by feeding them so that the web is cut substantially parallel to the rotation axis of the blades. In the conventional cutting blade having the above-mentioned construction, the upper blade and the lower blade have a cutting edge shape as shown by reference numbers 50 and 51 in FIG. 8, or as shown in FIGS. 9 and 10. It was shaped like a cutting edge. That is, in the conventional cutting blade, the upper blade and the lower blade are formed such that the blade tips have a right angle or a sharp shape cut toward the blade on the other side. Regarding this type of round blade, for example, Japanese Utility Model Laid-Open No. 53-117685 and 53-
It is described in Japanese Patent No. 117687.

(Problems to be solved by the invention) By the way, a photographic roll film is cut as described above after the emulsion is applied on the surface of a support made of a plastic web. The shape of both ends of the film cut by the cutting round blade tool is, for example, as shown in FIG. In FIG. 11, 60 is a support and 61 is an emulsion. When cut into such a shape, the support 60 projects outward from the emulsion 61 on one side end surface of the film and the opposite side on the other side end surface. In this way, if the emulsion 61 or the support 60 is projected outward from the side, for example, when the film is fed in the camera, the sides of the emulsion rub against parts in the camera, and the emulsion falls off like powder in the camera. Sometimes. The peeled powdery emulsion adheres to the surface of the film to deteriorate the image quality or cause the camera to malfunction. Similar troubles may occur not only in cameras but also in production facilities and development processors. Such defects are often noticeable especially in motion picture films.

The problems with photographic film have been described above.
Also in other magnetic tapes, when the support is cut so that the magnetic material coated on the web-shaped support protrudes downwardly from the support, the powder of the magnetic material is removed by a video camera or the like. 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 amount from projecting to both side edges of the web.

The above-mentioned problems can be solved by cutting a photographic film, a magnetic tape, or the like into a state in which both ends of the support project outside the coating layer toward the image side. Therefore, it is an object of the present invention to provide a cutting round blade tool capable of cutting a web made of plastic or the like into a desired cut sectional shape.

(Means for Solving the Problem) The cutting circular blade tool of the present invention is a cutting circular blade tool composed of an upper blade and a lower blade that are circular blades that are rotated as described above. It is characterized in that at least one of the blade tip and the lower blade is chamfered so that the surface facing the mating blade gradually separates from the mating blade radially outward.

(Operation) If the upper blade, the lower blade, or both of the blade edges are chamfered as described above, a gap is created between the blade edge portion and the blade on the other side, and this gap causes the web to move from the blade edge portion. It becomes narrower as it is cut.
Therefore, the cut surface of the web has unevenness in the web thickness direction, and the amount of coming and going of this unevenness changes depending on the chamfered shape. Therefore, by appropriately setting the chamfered shape, both end surfaces of the web can be made to project outward more than the coating layer of the emulsion, magnetic material or the like on the surface.

(Examples) Hereinafter, the present invention will be described in detail based on examples shown in the drawings.

3 and 4 show a cutting circular blade tool according to an embodiment of the present invention. The annular lower blade 10 is fixed to a lower blade shaft 15 which is rotated by a drive device (not shown). Similarly, the annular upper blade 11 is fixed to the 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 10 and the upper blade 11 are arranged so that the cutting edge portions thereof overlap each other, and are rotated in the directions of the arrows in FIG.
The web-shaped film 20 is fed between the blades 10 and 11 in a state of being substantially parallel to the lower blade rotating shaft 10C and the upper blade rotating shaft 11C, and is continuously cut in the longitudinal direction thereof.

In this device, as shown in FIG. 1, the blade edge of the lower blade 10 is at a right angle, but the surface of the blade edge of the upper blade 11 facing the blade on the other side is gradually lowered outward in the radial direction. Chamfered away from the blade 10. Since such a chamfer is made, at the position (the biting point) where the film 20 begins to enter between the double-edged blades 10 and 11, as shown in FIG.
There is a gap between the blades 10 and 11, while the blades 10 and 11 are in contact with each other at the position between the rotating shafts 1C and 11C (center point of the shaft) as shown in FIG. Therefore, by appropriately setting the above-mentioned chamfered shape, the cut shape of the side cross section of the film 20 can be made as shown in FIG. Hereinafter, this point will be described in detail.

The cut surface on the right side of the film 20 in FIG. 5 remains on the lower blade 10 when cut by the lower blade 10 and the upper blade 11, so this is referred to as the lower blade side cut surface 20S, while on the left side The cutting surface of is cut by the upper blade 11, so this is referred to as the upper blade-side cutting surface 20U, and the unevenness amount of both cutting surfaces 20S and 20U is considered. As shown in FIG. 5, a support for the film 20
The cut position of the upper surface of 20A is defined as D, and the average protrusion amount A of the upper half of the support pair 20A and the average protrusion amount B of the lower half of the support pair 20A for this position D can be changed by changing the chamfered shape. To see if it changes. In this example, the chamfer height T (see FIG. 1) is constant at about 100 μm, and the chamfer width W is variously changed to obtain the protrusion amounts A and B.
I checked. The results are shown in FIG. 6 for the lower blade side cut section 20S and in FIG. 7 for the upper blade side cut section 20U. In addition, the amount of protrusion is − (minus) means that the cutting surface position is recessed inward from the cut position D. In this case, the meshing amount M (see FIG. 2) of the double blades 10 and 11 is about 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 D on the lower half side of the support, or can be recessed (upper side). Half side is always protruding). As can be seen from FIG. 7, the same applies to the upper blade side cut surface 20U. If the chamfer width W is about 20 μm or more, the lower half side of the upper blade side cutting section 20U projects outward than the cutting position D, and at this time, the upper half side of the lower blade side cutting section 20S also has the cutting position D.
Since the film is projected further outward, the left and right end surfaces of the support 20A are finally projected outward from the end surface of the emulsion 20B (which is substantially at the same position as the cut position D).
You will be able to cut 20.

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

Further, the cutting round blade tool of the embodiment described above is formed to cut a photographic film, but the cutting round blade tool of the present invention is, for example, the magnetic tape offset printing plate described above, Of course, it is also possible to cut a web having a coating layer on a web support such as photographic paper. Further, the apparatus of the above-mentioned examples is used for obtaining a cutting surface in which both end faces of the film support respectively project outward from the emulsion, but according to the apparatus of the present invention, It is also possible to obtain a cutting surface other than a simple cutting surface. That is, for example, as shown in FIGS. 6 and 7, the chamfered shape can be arbitrarily cut by changing the chamfered shape of the upper blade or the lower blade. Therefore, the chamfered shape is appropriately set according to the desired chamfered shape. do it.

(Effects of the Invention) As described in detail above, the cutting circular blade tool of the present invention is chamfered on the upper blade or the lower blade, and further on the cutting edges of both of them, and various cutting cross-sectional shapes depending on the shape of this chamfer. Since it can be changed, the present tool can optionally obtain a web having a desired side end face shape. And if this cutting blade is used for cutting the above-mentioned photographic film, it is possible to form a film in which both end faces of the support are projected outward from the emulsion side. It is possible to solve the problem that the emulsion peels off and the camera or the like malfunctions.

[Brief description of drawings]

1 and 2 are a sectional view and a sectional view showing the positional relationship between the upper blade and the lower blade at a film biting point and a shaft center point, respectively, of a cutting circular blade tool according to an embodiment of the present invention. FIG. 4 is a partially cutaway elevational view and a side view showing the cutting circular blade tool of the above embodiment, and FIG. 5 is a cross section of a photographic film cut by the cutting circular blade tool of the above embodiment. Schematic diagrams showing the shape, FIGS. 6 and 7 are graphs showing the relationship between the cutting edge chamfering of the cutting circular blade tool of the present invention and the width and the unevenness of the film cutting cross section, FIGS. 8, 9 and 10 are Conventionally, a cross-sectional view showing a cutting edge shape of a cutting circular blade tool, FIG. 11 is a schematic view showing a shape of a web cutting surface by a conventional cutting circular blade tool, FIG. 12 and FIG. 13 are respectively of the present invention. It is sectional drawing which shows the other example of the edge shape of the round blade tool for cutting. 10, 51 …… Lower blade, 10 C …… Upper blade rotating shaft 11, 50 …… Upper blade, 11 C …… Lower blade rotating shaft 20 …… Photographic film, 20 A …… Support 20 B …… Emulsion, 20 S …… Lower blade side cutting surface 20U …… Upper blade side cutting surface, M …… Amount of engagement between upper and lower blades T …… Chamfer height, W …… Chamfer width

Claims (1)

[Claims] 1. An upper blade and a lower blade, both of which are round blades, are arranged such that the portions in the vicinity of the respective blade edges overlap and are rotated, and the upper blade and the lower blade are substantially parallel to the axis of rotation between the upper blade and the lower blade. In a cutting circular blade tool that continuously cuts the fed web, the surface of at least one of the upper and lower blades that faces the opposite blade gradually becomes radially outward. A round blade tool for cutting, characterized by being chamfered away from the edge.