High speed interfolder

• US 20070082800A1
• Filed: 10/07/2005
• Published: 04/12/2007
• Est. Priority Date: 10/07/2005
• Status: Active Grant

• Current Assignee: C.G. Bretting Manufacturing Co., Inc.
• Original Assignee: C.G. Bretting Manufacturing Co., Inc.
• Inventors: Kauppila, Greg
• Granted Patent: US 7,452,321 B2
• Time in Patent Office: Days
• US Class Current: 493/427
• CPC Class Codes: B65H 45/162 with folding jaw cylinders
• CPC Class Codes: B65H 45/24 Interfolding sheets, e.g. cigarette or toilet papers

Abstract

An interfolding apparatus including a knife roll rotatable about an axis and operable to cut successive sheets from a stream of web material issuing from a source in a downstream direction. A folding roll is positioned downstream of the knife roll and is rotatable in a first direction at a first roll speed. An additional roll is disposed adjacent to the folding roll and is rotatable about an axis in a second direction at a second roll speed. The additional roll is operable to receive the successive sheets and release the successive sheets in the downstream direction toward the folding roll. The folding roll and the additional roll define a nip therebetween, the successive sheets passing through the nip. The first roll speed of the folding roll is different from the second roll speed of the additional roll, the difference in speed between the folding roll and the additional roll operable to overlap adjacent portions of the successive sheets onto the folding roll.

Claims

1. An interfolding apparatus comprising:

a knife roll rotatable about an axis and operable to cut successive sheets from a stream of web material issuing from a source in a downstream direction;

a folding roll positioned downstream of the knife roll, the folding roll rotatable in a first direction at a first roll speed; and

an additional roll disposed adjacent to the folding roll and rotatable about an axis in a second direction at a second roll speed, the additional roll operable to receive the successive sheets and release the successive sheets in the downstream direction toward the folding roll;

wherein the folding roll and the additional roll define a nip therebetween, the successive sheets passing through the nip, and wherein the first roll speed of the folding roll is different from the second roll speed of the additional roll, the difference in speed between the folding roll and the additional roll operable to overlap adjacent portions of the successive sheets onto the folding roll.

2. The apparatus of claim 1, wherein the folding roll includes a plurality of grippers, and a plurality of tuckers.

3. The apparatus of claim 1, wherein the folding roll has a first roll speed approximately equal to ⅔

of the second roll speed of the additional roll.

4. The apparatus of claim 1, wherein the additional roll adjacent the folding roll is a lap roll, and wherein the lap roll includes a plurality of vacuum ports and a plurality of relief areas.

5. The apparatus of claim 4, wherein each of the plurality of relief areas is configured to receive a portion of one of the successive sheets during transfer of the one of the successive sheets from the lap roll to the folding roll.

6. The apparatus of claim 4, wherein the plurality of vacuum ports are spaced about a circumference of the lap roll to ensure contact between the lap roll and at least a portion of the sheets as the sheets pass through the nip between the lap roll and the folding roll.

7. The apparatus of claim 4, wherein the folding roll includes at least one vacuum port such that as the sheets pass through the nip between the lap roll and the folding roll, a leading edge of the sheets is transferred from the lap roll to the folding roll and is held on the folding roll by one of the at least one vacuum port of the folding roll.

8. The apparatus of claim 7, wherein a remaining portion of the sheet is held onto the lap roll by the plurality of vacuum ports of the lap roll as the sheets pass through the nip, and wherein the difference in roll speed between the folding roll and the lap roll creates slack in the sheet between the leading edge and the trailing portion.

9. The apparatus of claim 1, further comprising a tail roll disposed adjacent the folding roll to define a nip therebetween.

10. The apparatus of claim 9, wherein the folding roll includes at least one tucker and the tail roll includes at least one relief area, the tucker forcing a portion of a sheet within the relief area during rotation of the folding roll to form a bend in the sheet.

13. The method of claim 11, wherein transferring each sheet to the folding roll includes applying a vacuum to a leading edge of the sheet with a folding roll vacuum port, and applying a vacuum to a trailing portion of the sheet with multiple additional roll vacuum ports.

16. The method of claim 11, further comprising providing a tail roll adjacent the folding roll to define a nip therebetween.

17. The method of claim 16, further comprising providing at least one tucker on the folding roll and providing at least one relief area on the tail roll, the tucker forcing a portion of a sheet within the relief portion during rotation of the folding roll to form a bend in the sheet.

11. A method of interfolding sheets of material, the method comprising:

issuing web material in a downstream direction from a source;

cutting with a knife roll the stream of web material into successive sheets;

rotating an additional roll at a first roll speed;

transferring each sheet to the additional roll;

rotating a folding roll at a second roll speed;

transferring each sheet to the folding roll;

slowing the sheet with the folding roll, overlapping adjacent portions of the successive sheets onto the folding roll; and

interfolding the overlapped sheets.

12. The method of claim 11, wherein slowing the sheet with the folding roll includes slowing the sheet to ⅔

the first roll speed of the additional roll.

14. The method of claim 11, further comprising applying a vacuum to a leading edge of the sheet transferred to the folding roll via a single vacuum port.

15. The method of claim 14, further comprising applying a vacuum to a remaining portion of the sheet such that the remaining portion of the sheet is held onto the additional roll.

18. An interfolding apparatus comprising:

a knife roll rotatable about an axis and operable to cut sheets from a stream of web material issuing from a source in a downstream direction;

a folding roll positioned downstream of the knife roll and adapted to receive the sheets, the folding roll rotatable in a first direction; and

a lap roll adjacent the folding roll rotatable about an axis in a second direction, the lap and folding roll defining a nip therebetween;

wherein the sheets are directly transferred from the lap roll to the folding roll to overlap adjacent portions of successive sheets onto the folding roll.

19. The apparatus of claim 18, further comprising a tail roll disposed adjacent the folding roll, the tail roll and folding roll defining a second nip therebetween.

20. The apparatus of claim 19, wherein the folding roll includes at least one tucker and the tail roll includes at least one relief area, the tucker forcing a portion of a sheet within the relief area during rotation of the folding roll to form a bend in the sheet.

21. The apparatus of claim 18, wherein the folding roll rotates at a first roll speed, and wherein the lap roll rotates at a second roll speed, the first roll speed being slower than the second roll speed.

22. The apparatus of claim 21, wherein the first roll speed is approximately equal to ⅔

of the second roll speed.

23. The apparatus of claim 21, wherein the difference between the first and second roll speeds results in an overlap between adjacent portions of successive sheets.

24. The apparatus of claim 18, wherein the folding roll includes a plurality of grippers and a plurality of tuckers.

25. The apparatus of claim 24, wherein the lap roll includes a plurality of vacuum ports and a plurality of relief areas.

26. The apparatus of claim 25, wherein each of the plurality of relief areas is configured to receive a portion of a sheet during transfer of the sheet from the lap roll to the folding roll.

27. The apparatus of claim 18, wherein the folding roll includes at least one vacuum port such that as sheets pass through the nip between the lap roll and the folding roll, a leading edge of the sheets is transferred from the lap roll to the folding roll and is held onto the folding roll by one of the at least one vacuum port of the folding roll.

28. The apparatus of claim 27, wherein a remaining portion of the sheet is held onto the lap roll by a plurality of vacuum ports of the lap roll as the sheets pass through the nip, and wherein slack is created in the sheet between the leading edge and tailing portion as the sheets pass through the nip.

29. A method of interfolding sheets, the method comprising:

issuing web material in a downstream direction from a source;

cutting with a knife roll the stream of web material into sheets;

transferring each sheet to a rotating lap roll;

transferring each sheet directly from the lap roll to a rotating folding roll;

overlapping a trailing edge of a first sheet with a leading edge of a second successive sheet on the folding roll; and

interfolding the overlapped sheets.

30. The method of claim 29, wherein transferring each sheet to the rotating folding roll includes slowing the sheet.

31. The method of claim 30, wherein slowing the sheet with the folding roll includes slowing the sheet to ⅔

the first speed of the lap roll.

32. The method of claim 29, wherein transferring each sheet to a lap roll includes applying a vacuum to a leading edge of the sheet with a folding roll vacuum port, and applying a vacuum to a trailing portion of the sheet with multiple lap roll vacuum ports.

33. The method of claim 32, further comprising applying a vacuum to a leading edge of the sheet transferred to the folding roll via a single vacuum port.

34. The method of claim 32, further comprising applying a vacuum to a remaining portion of the sheet such that the remaining portion of the sheet is held onto the lap roll.

35. The method of claim 29, further comprising providing a tail roll adjacent the folding roll to define a nip therebetween, and rotating the tail roll to roll the overlapped sheets through the nip.

36. The method of claim 35, further comprising providing at least one tucker on the folding roll and providing at least one relief area on the tail roll, the tucker forcing a portion of a sheet within the relief portion during rotation of the folding roll and tail roll to form a bend in the sheet.