Device and method for manipulating a fibrous web

摘要

The invention relates to a device and a method for manipulating a fibrous web (10). The device comprises at least one blower (21A, 21B) provided with a flow-preventing element (24A, 24B) which is arranged to produce at least one blow (26A, 26B) substantially in the direction of the fibrous web (10), and a friction element (28) against which the fibrous web (10) is arranged to be pressed at least partially from the effect of said blow (26A, 26B) and flow-preventing element (24A, 24B) to apply a friction force resisting the motion of the fibrous web (10) to the fibrous web (10). According to the invention, the blow (26A, 26B) is directed substantially away from the friction element (28) and the friction element (28) comprises a surface profile which is arranged such that, from the effect of said at least one blow (26A, 26B), a continuous vacuum is created on the surface of the fibrous web (10) on the side of the friction element (28). Due to its intensified friction effect, the device according to the invention is applicable especially for board and, by means of it, it is possible to form e.g. an air cutting device in the tail-threading section of a board machine.

主权项

1. A device (14) for manipulating a fibrous web (10), which device comprises
a first blower (21A) provided with a flow-preventing element (24A) to produce a first blow (26A) substantially opposite to the motion direction of the fibrous web (10), a second blower (21B) provided with a flow-preventing element (24B) to produce a second blow (26B) substantially in the direction of the motion direction of the fibrous web (10), a friction element (28) against which the fibrous web (10) is arranged to be pressed at least partially from the effect of said blows (26A, 26B) and flow-preventing elements (24A, 24B) to apply a friction force resisting the motion of the fibrous web (10) to the fibrous web (10),whereby
the friction element (28) is located between the first and the second blower (21A, 21B), whereby the blows (26A, 26B) are directed substantially away from said friction element (28) such that at least the most part of the friction element is located on the backside of a plane defined by the outlet opening and/or openings and the start direction of each blow (26A, 26B), and the friction element (28) comprises a surface profile which is arranged such that, from the effect of said blows (26A, 26B) and flow-preventing elements (24A, 24B), a continuous vacuum is provided on the surface of the fibrous web (10) on the side of the friction element (28), characterized in that said surface profile deviates from a planar one.