Interfolder with pre-forming transfer roll

• US 20070082801A1
• 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: Ryczek, Chad, Kauppila, Greg, Couturier, Dennis
• Granted Patent: US 7,458,927 B2
• Time in Patent Office: Days
• US Class Current: 493/435
• 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, a first interfolding roll, a second interfolding roll, and a transfer roll. The knife roll cuts sheets from a stream of web material issuing from a source in a downstream direction. The first interfolding roll is positioned downstream of the knife roll and receives the sheets. The first interfolding roll rotates in a first direction and the second interfolding roll rotates in a second direction. The first and second interfolding rolls interfold the sheets with additional sheets received by the second interfolding roll. A transfer roll is positioned between the knife roll and the first interfolding roll. The transfer roll has a non-uniform surface configuration and rotates in the second direction and receives the sheets from the knife roll, forms a bend in each of the sheets, and transfers the formed sheets to the first interfolding roll.

Claims

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

a second interfolding roll rotatable in a second direction and disposed adjacent to the first interfolding roll to define a nip therebetween, the first and second interfolding rolls rotatable to interfold the sheets with additional sheets received by the second interfolding roll; and

a transfer roll positioned between the knife roll and the first interfolding roll, the transfer roll having a non-uniform surface configuration, the transfer roll rotatable in the second direction and operable to receive the sheets from the knife roll, to form a bend in each of the sheets received from the knife roll, and to transfer the formed sheets to the first interfolding roll.

2. The apparatus of claim 1, wherein the transfer roll includes a plurality of forming blades, and wherein each of the plurality of forming blades contacts a middle portion of a respective sheet to form the bend in the middle portion of the sheet.

3. The apparatus of claim 2, wherein the interfolding roll includes a plurality of grippers, and wherein each of the plurality of grippers receives one of the plurality of tuckers during the transfer of the sheet from the transfer roll to the first interfolding roll.

4. The apparatus of claim 1, wherein the transfer roll includes a plurality of vacuum ports, and wherein a first vacuum port of the plurality of vacuum ports retains a leading edge of the sheet and wherein a second vacuum port of the plurality of vacuum ports retains a trailing edge of the sheet.

5. The apparatus of claim 1, wherein the first interfolding roll includes a plurality of vacuum ports, and wherein a third vacuum port of the plurality of vacuum ports retains a leading edge of the sheet, and wherein a fourth vacuum port of the plurality of vacuum ports retains a trailing edge of the sheet.

6. The apparatus of claim 1, wherein each sheet has a leading edge, a middle portion, and a trailing edge, and wherein the leading edge of each sheet on the transfer roll remains the leading edge of the sheet on the first interfolding roll after being transferred to the first interfolding roll.

7. The apparatus of claim 1, wherein each sheet extends across a circumferential length on the cutting roll and extends across a second circumferential length on the transfer roll, wherein the first circumferential length is greater than the second circumferential length.

8. The apparatus of claim 1, wherein each sheet extends across a first circumferential length on the transfer roll and a second circumferential length on the first interfolding roll, wherein the first circumferential length is the same as the second circumferential length.

9. The apparatus of claim 1, wherein the knife roll is disposed adjacent the transfer roll to define a nip therebetween, wherein each sheet is transferred directly from the knife roll to the transfer roll.

10. The apparatus of claim 9, wherein the transfer roll includes at least one tucker and the knife roll includes at least one groove, the tucker forcing a portion of a sheet within the groove during rotation of the knife roll and transfer roll to form the bend.

11. The apparatus of claim 1, wherein the transfer roll is disposed adjacent to the first interfolding roll to define a nip therebetween, wherein each sheet is transferred directly from the transfer roll to the first interfolding roll.

12. The apparatus of claim 11, wherein the nip between the transfer roll and the first interfolding roll defines a tight roll gap operable to iron the transferred sheet as the transfer roll and first interfolding roll rotate together.

13. The apparatus of claim 1, wherein the knife roll, the transfer roll, and the first interfolding roll include vacuum ports operable to transfer sheets from the knife roll to the transfer roll and to transfer sheets from the transfer roll to the first interfolding roll.

14. The apparatus of claim 1, wherein the transfer roll defines a roll radius, and wherein the bend is substantially different from the roll radius.

15. The apparatus of claim 14, wherein the bend defines a bend radius, the bend radius being substantially smaller than the roll radius.

16. 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 sheets;

transferring each sheet to a transfer roll;

forming with the transfer roll a bend in the middle portion of each sheet;

transferring each formed sheet to an interfolding roll; and

interfolding the formed sheet on the interfolding roll with at least one other sheet from an adjacent interfolding roll.

17. The method of claim 16, further comprising

extending each sheet across a first circumferential length on the knife roll;

and

extending each sheet across a shorter, second circumferential length on the transfer roll.

18. The method of claim 17, further comprising

extending each sheet across a third circumferential length on the first interfolding roll that is the same as the second circumferential length.

19. The method of claim 16, further comprising

maintaining a leading edge of each formed sheet on the transfer roll as the leading edge of the formed sheet on the interfolding roll.

20. The method of claim 16, wherein transferring each formed sheet to an interfolding roll includes transferring a leading edge of the formed sheet on the transfer roll to the first interfolding roll.

21. The method of claim 16, wherein forming a bend includes forcing a middle portion of a sheet within a groove of the knife roll with a forming blade of the transfer roll.

22. The method of claim 16, further comprising receiving the bend of the sheet in a gripper of one of the interfolding rolls and inserting a tucker of the adjacent interfolding roll into the gripper after the sheet has been received in the gripper.