JPH06320492A - Web parting method and device - Google Patents

Abstract

PURPOSE:To perform parting of a raw fabric web accurately and beside in a state to prevent the occurrence of meandering even when a web surface is locally continued and brought into elongation deformation, in a parting device to part a wide raw fabric web by means of a cutter to form a narrow belt body. CONSTITUTION:A stretch frame 11 to perform stretching operation of a raw fabric web 1 is arranged in an entrance passage to a cutter 2 for the raw fabric web 1. The stretching frame 11 has a groove 12 brought into external contact with the raw fabric web 1. A vacuum pressure is exerted on the groove 12, a web surface is pulled in the groove 12, and the raw fabric web 1 is forcibly stretched in a longitudinal direction. Under a stretched state, the raw fabric web 1 is parted by means of the cutter 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting method and a device for cutting a wide web into small pieces.

[0002]

2. Description of the Related Art When the surface state of a web to be cut is irregular, for example, when the web surface is stretched and deformed to form gentle wrinkles, the cutting is performed with a high-precision cutting device. Even if it does, the shapes and dimensions of the divided strips greatly vary, resulting in defective processing. For example, the dividing line meanders or the dividing width dimension varies widely.

As a conventional technique for avoiding such a defect at the time of cutting, it is known that an expanding roll is arranged in a web entrance path to the cutting blade and the roll is used to stretch the web surface (unknown document). Expanding roll
A roll shaft that is curved, a spiral groove that twists in the opposite direction from the center of the roll peripheral surface to the left and right ends,
Some rubber rolls have different friction coefficients embedded in a spiral shape on the peripheral surface, but they are common in that the web is stretched in the width direction.

[0004]

As described above, the form in which the web is expanded in the width direction by the expanding roll is effective when the entire surface of the web is stretched or distorted, but the stretch deformation or the like is locally generated. In the case where it partially occurred, it could not be sufficiently expanded and still failed. For example, when manufacturing a magnetic tape, a raw web having a magnetic layer coated on one side is divided into a predetermined width to form a magnetic tape, and a stretch deformation region is formed at a width of several tens of centimeters in the widthwise center of the raw web. When the stretch deformation region is continuous in the longitudinal direction of the web, the expanded roll cannot be used to sufficiently stretch the web surface, and the separated magnetic tape has a defective width dimension. There was a meander. It is considered that this is because the base film on the proper web surface continues to maintain its position against the tension in the width direction.

Therefore, an object of the present invention is to apply a tension equivalent to that of a normal web surface to a partially stretched and deformed portion generated on the web surface so that the web can be appropriately cut, and the yield based on the failure of the cutting can be improved. To eliminate the decline of.

[0006]

According to a method of cutting a web of the present invention, a raw web 1 which is continuously fed in one direction is divided into narrow strips 3 by a cutter 2 provided on a feeding path. To do. A stretch frame 11 that crosses the original web 1 in the width direction and circumscribes one side of the original web 1 is provided in the approach path of the original web 1 to the cutter 2. Applying vacuum pressure to the groove 12 provided in the expansion frame 11,
The original web 1 passing through the opening of the groove 12 is drawn into the groove 12, and the original web 1 is divided by the cutter 2 in a state of being stretched in the longitudinal direction.

Further, in the web cutting apparatus of the present invention, the cutter 2 is arranged in the feed path of the original web 1. Original web 1
A stretch frame 11 for stretching the original web 1 is arranged on the approach path to the cutter 2. The stretch frame 11 has a groove 12 that traverses the original web 1 in the width direction and circumscribes one side thereof. The groove 12 is connected to a separately provided vacuum source 14 via a passage 13. The original web 1 is fed to the cutter 2 while a vacuum pressure is applied to the original web 1 passing through the opening of the groove 12.

[0008]

[Function] Original web 1 fed toward cutter 2
Is drawn into the groove 12 by the vacuum pressure acting on the groove 12 when passing through the expansion frame 11. That is, the original web 1 passes through the fictitious detour in the groove 12 and then the stretch frame 1
Pass 1. At this time, if the web surface of the original web 1 is stretched and deformed, the web surface is excessively drawn into the groove 12 in accordance with the amount of deformation. As a result, the original web 1 is stretched in the longitudinal direction, and the web surface when passing the cutter 2 can be made flat.

[0009]

According to the present invention, a stretch frame 11 for sucking the web surface by vacuum pressure is provided in the entrance path of the raw web 1 to the cutter 2, and the raw web 1 passes through the groove 12 of the stretch frame 11. In between, the web surface is pulled into the groove 12 and the original web 1
Was fed to the cutter 2 in a state of being stretched in the longitudinal direction and cut into pieces. As a result, even if a stretch deformation portion or the like is locally or partially generated on the web surface, it can be appropriately divided in a state where the deformation portion is flatly extended, and the division width at the extension deformation portion exceeds the allowable amount, It is possible to eliminate the defective dividing such as the dividing line meandering, eliminate the decrease in the yield, and improve the productivity accordingly.

[0010]

1 to 4 show an embodiment in which the present invention is applied to a cutting device for a magnetic tape. In FIG. 2, reference numeral 1 is a wide-width feeding device which continuously feeds in one direction at a constant speed. The original web. In the original web 1, a magnetic layer is formed by coating on the upper surface of the base film, and a back coat layer is formed on the lower surface of the film if necessary. The raw web 1 is divided into a large number of narrow strips (magnetic tapes) 3 while passing through the cutter 2, and is guided up and down via guide rollers 4 and 5, respectively, and then wound up respectively. It is rolled up into a disk shape at 6. As shown in FIG. 3, the cutter 2 is configured by arranging a pair of upper and lower disc-shaped cutter blades 7 and 8 in a linear array, and the upper and lower cutter blades 7 and 8 are respectively arranged in the arrow direction. The original web 1 is rotatably driven and divided into a predetermined width. The center axis of rotation of each cutter blade 7 and 8 is orthogonal to the feed direction of the original web 1.

Although the original web 1 is originally formed flat, it may be locally or partially stretched and deformed during various processings and treatments. In the case of the original web 1 shown in FIG. 4, the center in the width direction is continuously stretched and deformed in the longitudinal direction. Reference numeral 10 indicates the deformed portion. In this way, even when the deformed portion 10 is formed on a part of the web surface,
In order to divide the web 3 from the raw web 1 in an appropriate state, a stretching frame 11 is provided on the lower surface of the approach path of the raw web 1 to the cutter 2, and the raw web 1 is stretched in the longitudinal direction. is doing.

The expansion frame 11 is made of steel or a metal material equivalent to steel, and the original web 1 is arranged in a state of traversing in the direction orthogonal to the longitudinal direction thereof, and the upper surface 11a of the frame is arranged.
Is brought into contact with the lower surface of the original web 1. A groove 12 that opens on the frame upper surface 11a is formed in the expansion frame 11 along the longitudinal direction, and this groove 12 is connected to a vacuum source 14 such as a vacuum pump or a vacuum blower via a passage 13.

In order to prevent abrasion of the original web 1 passing through the frame upper surface 11a, both end edges 15 of the frame upper surface 11a and the opening edges 16 of the grooves 12 are rounded with appropriate radius values as shown in FIG. deep. Further, after the frame upper surface 11a and the above-mentioned edge portions 15 and 16 are finished to be smooth, they are subjected to a plating treatment or a polytetrafluoroethylene-impregnated plating treatment to give them high hardness and sufficient surface smoothness.

The opening width of the groove 12 is 1 / the width of the original web 1.
The groove depth is set to 1000 to 1/10, preferably about 1/100, and the groove depth is set to 1 to 10 times the opening width. In this embodiment, the width of the original web 1 is 100 cm, while the width of the groove 1 is 100 cm.
The opening width of 2 was 10 mm, and the groove depth was 7 mm. The cutting device configured as described above feeds the original web 1 to the cutter 2 in a state in which a vacuum pressure is applied to the groove 12 and performs the cutting.

When the original web 1 passes through the opening of the groove 12, the inside of the groove 12 is in a negative pressure state, so that all the parts in the width direction are drawn into the groove 12 in an inverted Ω shape (large). Pressed at atmospheric pressure). At this time, since the suction force that balances the feeding tension of the original web 1 acts on the entire surface of the web,
The deformed portion 10 is drawn deeper into the groove 12 than the proper web surface and stretched in the longitudinal direction of the original web 1.
Therefore, between the expansion frame 11 and the cutter 2, the deformation portion 10
Is also flattened like other web surfaces and is divided in that state. The strip 3 thus divided has no variation in width dimension, and the dividing line does not meander. Further, in the case of a magnetic tape, the cut state may directly affect the magnetic characteristics, but the cut state is not defective.

In order to confirm the cutting accuracy when the spreading frame 11 according to the present invention is used, the case where the raw web 1 is cut according to the above-mentioned embodiment and the vacuum pressure supply to the spreading frame 11 is stopped. The deformation part 1
The strip 3 containing 0 was measured. The measurement items were the width of the strip 3 and the amount of meandering. Regarding the amount of meandering, the deviation between the actual center line in the width direction and the true center line in the width direction of the strip 3 was measured using a meandering amount measuring device (#ZDR type manufactured by Kosaka Laboratory). The result is shown in FIG. As is clear from the chart shown in FIG. 5, in the comparative example in which the supply of the vacuum pressure to the spreading frame 11 is stopped, the width dimension exceeds the allowable value and the fluctuation range is large, but in the embodiment of the present invention, The width dimension is located near the center of the allowable range, and its fluctuation range is small. Regarding the meandering of the dividing line, the comparative example meanders to both sides in the width direction with respect to the true center line, and the change width is large (about 35 μm).
On the other hand, in the example of the present invention, the meandering width could be suppressed to about 20 μm.

FIG. 6 shows another embodiment of the present invention. There, a guide surface 18 having a partial arc shape is provided on the approach path to the cutter 2.
The tape guide 19 having the above is arranged, and the expansion frame 11 is formed using this tape guide 19. Specifically, the groove 12 is opened in the middle of the guide surface 18, the groove 12 is connected to the vacuum source 14 through the passage 13, and the original web 1 that moves along the guide surface 18 is vacuumed in the groove 12. It was made to expand in the longitudinal direction by the action of pressure. In a transient operating state such as starting, accelerating, decelerating, or stopping the cutting device, the tension of the original web 1 fluctuates, but in such a case, the web surface is excessively drawn into the groove 12. In order to avoid the
It is preferable that the vacuum pressure applied to 2 is synchronized and varied.

In addition to the above-described embodiment, the spreading frame 11 can be arranged so as to be circumscribed on the upper surface side of the original web 1. Cutter 2
Does not need to use a circular blade as a cutter blade.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part of a cutting device.

FIG. 2 is an explanatory diagram showing an outline of a cutting device.

FIG. 3 is a cross-sectional view of a cutter.

FIG. 4 is a perspective view of a cutting device.

FIG. 5 is a chart showing a measurement result of a divided strip along with a comparative example.

FIG. 6 is a cross-sectional view showing another embodiment of the spreading frame.

[Explanation of Codes] 1 Original web 2 Cutter 3 Band 11 Extension frame 12 Groove 13 Passage 14 Vacuum source

Claims (2)

[Claims] 1. A method of dividing a raw web 1 which is continuously fed in one direction into a narrow strip 3 by a cutter 2 provided on a feeding path. An extension frame 11 that crosses the original web 1 in the width direction and is circumscribed on one side of the extension web 11 is provided on the approach path of the cutter 2 by applying a vacuum pressure to the groove 12 provided in the extension frame 11. , Groove 1
2. A method for cutting a web, characterized in that the original web 1 passing through the opening 2 is drawn into a groove 12, and the original web 1 is cut in a state of being stretched in a longitudinal direction by a cutter 2. 2. A cutter 2 is arranged in a feed path of the original web 1, and a stretch frame 11 for expanding the original web 1 is arranged in an approach path of the original web 1 to the cutter 2. The expansion frame 11 has a groove 12 that traverses the original web 1 in the width direction and circumscribes one surface thereof. The groove 12 is connected to a separately provided vacuum source 14 through a passage 13. A web cutting device configured to feed the raw web 1 to the cutter 2 in a state where a vacuum pressure is applied to the raw web 1 passing through the opening of the groove 12.