JP2003080592A - Nip roll device and nipping method for sheetlike material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a nip being uniform substantially in the direction of width irrespective of the running direction of a sheetlike material and thereby to attain stabilization of production, reduction of a flaw or a wrinkle brought about in running and consequent stabilization of a quality. SOLUTION: In a device of nip rolls 2 and 3 for the sheetlike material 1 which is equipped with the paired nip rolls 2 and 3 nipping the sheetlike material 1 in running, at least the nip roll 2 on one side is provided with a backup roll 5 which presses the central parts in the axial direction of the nip rolls 2 and 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nip roll device and a nip method for a sheet material.

[0002]

2. Description of the Related Art A nip roll device has been conventionally used for stretching a sheet material such as a resin film.

In such a nip roll device, as the width of the sheet-like material becomes wider, the nip roll is more likely to bend, and the bending of the nip roll weakens the pressure applied to the widthwise central portion of the sheet-like material, causing defective drawing. Will be.

Therefore, the nip roll itself is changed to a drum-shaped crown roll to increase the pressure applied to the central portion in the width direction of the sheet-like material, or as shown in Japanese Patent Laid-Open No. 10-45292, the nip rolls arranged above and below. Among these, the weight of the central portion of the nip roll disposed above is made heavy, and gravity is used to correct the pressure applied to the central portion in the width direction of the sheet-shaped material.

[0005]

However, when the crown roll is used, the traveling speed of the sheet-shaped material is different between the central portion and the both end portions in the axial direction of the crown roll, and therefore the speed difference causes wrinkles and scratches. May cause

Further, as shown in Japanese Patent Application Laid-Open No. 10-45292, when a nip roll having a heavy axial center portion is used, it is effective for nipping a sheet-like object traveling in the horizontal direction. Even if there is a problem that it is not effective for nipping a sheet material traveling in the vertical direction, or even if nipping a sheet material traveling in the horizontal direction, the weight of the central part in the axial direction is increased. The above nip roll has a problem that the amount of flexure changes when the nip pressure is changed, and as a result, the desired effect cannot be obtained.

Therefore, an object of the present invention is to solve the above problems and to expect a uniform nip in the width direction regardless of the traveling direction of the sheet-like material, thereby stabilizing production and An object of the present invention is to provide a nip roll device and a nip method for a sheet-like material that can stabilize the quality by suppressing the occurrence of scratches and wrinkles during traveling.

[0008]

In order to solve the above problems, according to the invention described in claim 1, at least a sheet-shaped nip roll device having a pair of nip rolls for nipping a traveling sheet-shaped product is provided. One of the features of the nip roll device is a sheet-like product in which one of the nip rolls is provided with a backup roll that presses the central portion of the nip roll in the axial direction.

According to the first aspect of the present invention having such a structure, the sheet-like material is obtained by pressing the central portion in the axial direction of at least one nip roll with the backup roll to increase the pressing force in the central portion in the axial direction. Regardless of the running direction, a uniform nip can be expected in the width direction, so that production can be stabilized, and scratches and wrinkles can be suppressed during running to stabilize quality. .

According to a second aspect of the present invention, in the nip method for nipping a traveling sheet with a pair of nip rolls, at least one of the nip rolls is pressed by a backup roll at the central portion in the axial direction, and the axial line is pressed. It is characterized by a nip method of a sheet-like material for increasing the pressing force at the central portion in the direction.

According to the invention of claim 2 having such a configuration, it is possible to obtain the same effect as that of claim 1.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Specific embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show an embodiment of the present invention.

First, the structure will be described. A pair of nip rolls 2 and 3 capable of nipping the traveling sheet 1 is provided. Here, the material of the sheet-like material 1 is, for example, PP or P.
For example, ET. The nip rolls 2 and 3 may be arranged on the left and right as shown in FIG. 1, or may be arranged on the top and bottom although not particularly shown.

The nip rolls 2 and 3 have, for example, a roll surface length of about 4000 mm and a roll outer diameter of about 300 mm.
A solid roll made of carbon steel of mm is used. One nip roll 2 is the driven side and the moving side, and the other nip roll 3 is the driving side and the fixed side. Therefore, one nip roll 2 is supported by the other nip roll 3 so as to be able to change the roll gap, and both ends of the one nip roll 2 are provided with a compression cylinder or the like that can expand and contract in the roll gap changing direction. Rolling down device 4
Are connected respectively. A drive device (not shown) is connected to the other nip roll 3. Further, a rubber lining such as an EPT rubber lining is applied to the outer peripheral surface of one nip roll 2 to form a so-called rubber roll. Further, the other nip roll 3 is a so-called iron roll without the rubber lining.

In this embodiment, at least one of the nip rolls 2 is provided with a backup roll 5 that holds the central portion of the nip roll 2 in the axial direction.

The backup roll 5 has a nipple
Roll surface length L1 1/3 to 1/2 of roll surface length L1
Use of L2 is effective for nip roll 2
It is preferable for pressing the central portion in the axial direction. For example, above
In the case of, the roll surface length of the backup roll 5 is almost
Made of carbon steel with a diameter of 2000 mm and an outer diameter of approximately 200 mm
Use a solid roll. In addition, the backup roll 5
Pressurized at both ends to expand and contract in the direction of roll gap change
A pressurizing device 6 such as a cylinder is connected to each. In addition,
The pressure applied by the pressure device 6 is, for example, a pressing pressure of 2
~ 5 kg / cm ²And so on.

Next, the operation of this embodiment will be described.

The sheet material 1 is passed between the pair of nip rolls 2 and 3, and the sheet material 1 is stretched by applying a reduction force between the pair of nip rolls 2 and 3 using a reduction device 4 such as a reduction cylinder. can do. in this case,
The final thickness of the sheet 1 is, for example, 15 to 40 μm.

At this time, one nip roll 2 is attached to the driven side,
By setting the other nip roll 3 on the drive side, it is possible to prevent slippage by matching the rotational speeds of the pair of nip rolls 2 and 3. In addition, by using one of the nip rolls 2 as a so-called rubber roll and the other nip roll 3 as a so-called iron roll, it is possible to efficiently apply a pressing force and suppress the occurrence of scratches and wrinkles on the sheet-shaped material 1.

Then, at least one nip roll 2
The central part in the axial direction is pressed by the pressurizing device 6 such as a pressurizing cylinder and the backup roll 5 to increase the pressing force in the central part in the axial direction. This makes it possible to increase the pressing force at the central portion in the axial direction regardless of the traveling direction of the sheet 1, and to expect a uniform nip substantially in the width direction, thereby stabilizing the production and It is possible to stabilize the quality by suppressing the occurrence of scratches and wrinkles during traveling.

Further, when the backup nip roll 2 on the driven side is provided, the structure of the nip roll device is simplified as compared with the case where the backup nip roll 3 on the driving side is apt to have a complicated mechanism. be able to.

Further, when the backup roll 5 is provided on the nip roll 2 constituted by a so-called rubber roll, the transfer mark by the backup roll 5 is less likely to be attached to the nip roll 2, so that the sheet-like material 1 is further scratched. It can be configured to be difficult.

[0024]

As described above, according to the first aspect of the present invention, the backup roll presses the central portion in the axial direction of at least one nip roll to increase the pressing force in the central portion in the axial direction. Regardless of the traveling direction of the object, you can expect a uniform nip in the width direction,
As a result, it is possible to stabilize production and stabilize quality by suppressing the occurrence of scratches and wrinkles during traveling.

According to the invention of claim 2, it is possible to exert a practically useful effect that the same effect as that of claim 1 can be obtained.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of the present invention.

FIG. 2 is a plan view of FIG.

[Explanation of symbols]

1 sheet 2 nip roll 3 Nip roll 5 backup roll

Claims (2)

[Claims] 1. A nip roll device for a sheet material, comprising a pair of nip rolls for nipping a traveling sheet material, wherein at least one of the nip rolls is provided with a backup roll for pressing the central portion in the axial direction of the nip roll. Nip roll device for sheet materials. 2. A nip method for nipping a traveling sheet with a pair of nip rolls, wherein at least one of the nip rolls is pressed by a backup roll at the central portion in the axial direction to increase the pressing force at the central portion in the axial direction. A nipping method for a sheet-like object, which is characterized in that