Claims
- 1-13. (canceled)
- 14. An apparatus for transferring a threading tail of a web, comprising:
a first drying cylinder having a first surface; a second drying cylinder having a second surface, the first drying cylinder and the second drying cylinder being spaced apart forming an empty space between the first surface and the second surface, the second surface being downstream of the first surface; a first turnover roll and a second turnover roll mounted to an arm in spaced apart relation, the first turnover roll and a second turnover roll positioned in the empty space between the first surface and the second surface with the first turnover roll nearer the first surface and the second turnover roll nearer the second surface; an air permeable belt mounted to form a loop about and supported by the first turnover roll and the second turnover roll and which is arranged to rotate so as to transport the threading tail of the web from the first surface to the second surface; at least one foil strip arranged within the belt loop to create a vacuum effect on a part of the belt loop between the first turnover roll and the second turnover roll; and a vacuum effect arranged in connection with the first turnover roll.
- 15. The apparatus of claim 14 wherein the first turnover roll is positioned at a distance of 2-10 mm from the first surface.
- 16. The apparatus of claim 14 wherein the first turnover roll is positioned at a distance of 3-6 mm from the first surface.
- 17. The apparatus of claim 14 wherein the vacuum effect arranged in connection with the first turnover roll comprises the first turnover roll having a perforated jacket with an inner circumference, on which the vacuum effect is arranged.
- 18. The apparatus of claim 17, wherein a vacuum box, which covers 20-70% of the inner circumference is fitted inside the perforated jacket.
- 19. The apparatus of claim 14 wherein, in order to create the vacuum effect, the first turnover roll has a jacket which has an outer circumference on which are defined longitudinally arranged grooves; and further comprising a chamber fitted inside the belt loop and arranged so that the chamber is delimited by the turnover roll and wherein a vacuum is arranged in the chamber and the vacuum extends from the chamber through the grooves in the jacket outer circumference to the belt loop.
- 20. The apparatus of claim 19, wherein the longitudinally arranged grooves essentially cover the total outer circumference of the first turnover roll and the grooves increase the surface area of the outer circumference of the turnover roll by 10-30%.
- 21. The apparatus of claim 19 wherein the longitudinally arranged grooves essentially cover the total outer circumference of the first turnover roll and the grooves increase the surface area of the outer circumference of the turnover roll by 15-25%.
- 22. The apparatus of claim 14 wherein the arm is articulated and supports the first turnover roll, the second turnover roll and th air permeable belt, so as to permit swiveling between a threading and a rest position.
- 23. The apparatus of claim 14 wherein the first turnover roll and the second turnover roll are separated by a distance of between 200-600 mm.
- 24. The apparatus of claim 14 wherein the first turnover roll and the second turnover roll are separated by a distance of between 300-500 mm.
- 25. The apparatus of claim 14 wherein at least two foil strips are arranged within the belt loop to create a vacuum effect on a part of the belt loop between the first turnover roll and the second turnover roll.
- 26. The apparatus of claim 14 wherein the belt loop has a longitudinal guide member arranged in the belt loop, and wherein the first turnover roll and the second turnover roll have portions defining a space corresponding to the longitudinal guide member which receives the guide member for retaining the belt loop on the the first turnover roll and the second turnover roll.
- 27. The apparatus of claim 26 wherein the guide member is selected from the group consisting of a protrusion attached to the belt loop and a fold in the belt loop.
- 28. The apparatus of claim 14 wherein the first drying cylinder and the second drying cylinder are part of a twin-wire dryer section of a paper machine;
wherein a plurality of drying cylinders belonging to the twin-wire dryer section are arranged on a first level and a second level, and on the first level there are third turnover rolls between the drying cylinders for leading a first wire through the consecutive drying cylinders, the first drying cylinder forming one dryer of the first level; wherein on the second level there are fourth turnover rolls between the drying cylinders for leading a second wire through the consecutive drying cylinders, the second drying cylinder forming one dryer of the second level; wherein the first turnover roll and the second turnover roll mounted to the arm are arranged between the first level and the second level to lead the threading tail of the web from an opening throat on the first level, the opening throat formed between a first drying cylinder and the first wire on the first level, over the empty space to a closing throat on the second level, the closing throat being formed between the second drying cylinder and the second wire on the second level; wherein the first turnover roll and the second turnover roll mounted to the arm are arranged to detach the threading tail of the web from the surface of the first drying cylinder and lead the detached threading tail of the web to the closing throat, and the first turnover roll and the second turnover roll mounted to the arm is arranged closely spaced from the first drying cylinder.
- 29. An apparatus for transferring a threading tail of a web in a paper machine, comprising:
a first surface; a second surface, the first surface and the second surface being spaced apart forming a empty space, the second surface being downstream of the first surface; a first turnover roll and a second turnover roll mounted to an arm in spaced apart relation, the first turnover roll and the second turnover roll being positioned in the empty space between the first surface and the second surface with the first turnover roll nearer the first surface and the second turnover roll nearer the second surface; an air permeable belt mounted to form a loop about and supported by the first turnover roll and the second turnover roll, the belt being arranged to rotate so as to transport a threading tail of the web from the first surface to the second surface; at least one foil strip arranged within the belt loop to create a vacuum effect on a part of the belt loop between the first turnover roll and the second turnover roll; and a vacuum effect arranged in connection with the first turnover roll.
- 30. The apparatus of claim 29, wherein the the first turnover roll and the second turnover roll mounted to the arm are positioned in a press section of the paper machine having at least one press roll, and at least one support fabric spaced from the press roll defining the empty space;
wherein the first turnover roll and the second turnover roll mounted to the arm are positioned to lead the web threading tail over the empty space from the press roll to the at least one support fabric and which the first turnover roll and the second turnover roll mounted to the arm is arranged to detach the threading tail of the web from the press roll and lead the detached web threading tail to the support fabric following the empty space; and wherein the first turnover roll is spaced from the at least one press roll.
- 31. The apparatus of claim 29 wherein the first turnover roll is positioned at a distance of 2-10 mm from the first surface.
- 32. The apparatus of claim 29 wherein the vacuum effect arranged in connection with the first turnover roll comprises, the first turnover roll having a perforated jacket with an inner circumference, on which the vacuum effect is arranged, and wherein a vacuum box, which covers 20-70%, of the inner circumference is fitted inside the perforated jacket.
- 33. The apparatus of claim 29 wherein, in order to create the vacuum effect, the first turnover roll has a jacket which has an outer circumference on which are defined longitudinally arranged grooves; and further comprising a chamber fitted inside the belt loop and arranged so that the chamber is delimited by the turnover roll and wherein a vacuum is arranged in the chamber and the vacuum extends from the chamber through the grooves in the jacket outer circumference to the belt loop.
- 34. The apparatus of claim 29 wherein the arm is articulated and supports the first turnover roll, the second turnover roll, and the air permeable belt, so as to permit swiveling between a threading and a rest position.
- 35. The apparatus of claim 29 wherein the first turnover roll and the second turnover roll are separated by a distance of between 200-600 mm.
- 36. The apparatus of claim 29 wherein the belt loop has a longitudinal guide member arranged in the belt loop, and wherein the first turnover roll, and the second turnover roll have portions defining a space corresponding to the longitudinal guide member which receives the guide member for retaining the belt loop on the the first turnover roll and the second turnover roll.
Priority Claims (1)
Number |
Date |
Country |
Kind |
20015023 |
Aug 2001 |
FI |
|
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application is a U.S. national stage application of International Application No. PCT/FI02/00687, filed Aug. 22, 2002, and claims priority on Finnish Application No. FI 20015023, Filed Aug. 22, 2001.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/FI02/00687 |
8/22/2002 |
WO |
|