Device and method for longitudinally stretching a film web

Patent metadata

Field	Value
Publication number	US-9333699-B2
Application number	US-201013509090-A
Country	US
Kind code	B2
Filing date	Nov 2, 2010
Priority date	Nov 10, 2009
Publication date	May 10, 2016
Grant date	May 10, 2016

Abstract

An apparatus for the longitudinal stretching of a film web includes at least one heater in which the film web can be heated, at least one cooling device in which the film web can be cooled, and at least a stretching unit in which the film web is stretched in its longitudinal direction. The stretching unit has a first transport roller having a first peripheral speed in the stretching operation, followed by a second transport roller having a second peripheral speed along the transport path of the film web from the first transport roller, with the second peripheral speed being greater than the first transport roller speed. The apparatus includes a pressing device with which the film web is pressed against the first transport roller along a line which is in the area of the release line of the film web from the first transport roller.

First claim

What is claimed is:

1. An apparatus for the longitudinal stretching of a film web, comprising:
a heater in which the film web can be heated;
a cooling device in which the heated film web is cooled;
a stretching unit disposed between the heater and the cooling device in a transport path of the film web, in which the film web is stretchable in a longitudinal direction thereof, the stretching unit including a first transport roller which runs at a first peripheral speed during stretching, and, along the transport path of the film web from the first transport roller, a second transport roller having a second peripheral speed that is higher than the first peripheral speed; and
at least one of a first pressing device with which the film web is pressed against the first transport roller along a line which is in an area of a release line of the film web from the first transport roller, and a second pressing device with which the film web is pressed against the second transport roller along a line which is in area of an input line of the film web to the second transport roller.

2. The apparatus according to claim 1 ,
further comprising
a first adjusting device that enables the at least one of the first pressing device and the second pressing device to be adjustable in a radial direction of a respective one of the first transport roller and the second transport roller.

3. The apparatus according to claim 1 ,
further comprising
a second adjusting device that enables the at least one of the first pressing device and the second pressing device to be adjustable in a circumferential direction of a respective one of the first transport roller and the second transport roller.

4. The apparatus according to claim 1 ,
wherein
the at least one of the first pressing device and the second pressing device is a pressure roller.

5. The apparatus according to claim 4 ,
wherein
at least areas of a peripheral surface of the pressure roller are coated with an elastomer.

6. A method of longitudinal stretching a film web, comprising:
heating the film web in a heater;
cooling the film web in a cooling device;
stretching the film web in a longitudinal direction thereof in a stretching unit disposed between the heater and the cooling device in a transport path of the film web, the stretching unit including a first transport roller having a first peripheral speed during the stretching, followed by a second transport roller along the transport path of the film web from the first transport roller, the second transport roller having a second peripheral speed that is higher than the first transport roller speed; and
with at least one of a first pressing device with which the film web is pressed against the first transport roller along a line which is in an area of a release line of the film web from the first transport roller, and a second pressing device with which the film web is pressed against the second transport roller along a line which is in the area of an input line of the film web to the second transport roller, pressing the film web,
with an area of −1 to +5 degrees from the release line and from −5 to +1 degrees from the input line lying in a rotational direction of the transport rollers, and
the at least one of the first pressing device and the second pressing device pressing the film web along a line that represents the line of contact of a tangential plane to the first transport roller or the second transport roller, and with said tangential plane being a common tangential plane of the first transport roller and the second transport roller.

Assignees

• Linkies Juergen
• Windmoeller & Hoelscher

Inventors

• Linkies Juergen

Classifications

• B29C48/08

  flexible, e.g. films · CPC title

• B29C55/065 Primary

  in several stretching steps · CPC title

• B29C48/914

  Cooling drums · CPC title

• B29C48/91

  Heating, e.g. for cross linking · CPC title