STRUCTURE OF MULTIPURPOSE SHEET FOLDING AND STACKING MACHINE

• US 20120202670A1
• Filed: 08/05/2009
• Published: 08/09/2012
• Est. Priority Date: 08/05/2009
• Status: Active Grant

• Current Assignee: Mtc-Macchine Trasformazione Carta SRL
• Original Assignee: M.T.C. - Macchine Trasformazione Carta, Srl
• Inventors: De Matteis, Alessandro
• Granted Patent: US 9,388,016 B2
• Time in Patent Office: Days
• US Class Current: 493/405
• CPC Class Codes: B65H 45/24 Interfolding sheets, e.g. cigarette or toilet papers

Abstract

A folding and stacking machine of a web of paper has first and second feed lines. The machine also has a folding section with folding rollers having a linear folding speed, VP. The folding rollers are adapted to receive a plurality of sheets of length L that can overlap each other for a fraction Y of their length L and to fold them into a plurality of panels P. The machine also has rollers adapted to feed at the folding speed V_P the series of cut sheets but not yet folded towards the folding rollers. The rollers are located at the confluence of the two sheet feeding lines. Upstream of the first and feed lines a single cutting section is provided to cut a web of paper that proceeds along a direction of movement at a speed V(1).

Claims

1. Folding and stacking machine, for making packages of folded and stacked sheets starting from a web of paper, or similar material, comprising:

a folding section comprising a first and a second folding roller, said first and second folding rollers adapted to fold said sheets into a plurality of panels and to form a stack of folded sheets;

a sheet feeding section for feeding sheets to said folding rollers, said sheet feeding section comprising a first sheet feeding means that is adapted to feed a first plurality of sheets to said folding rollers along a first feed line and a second sheet feeding means, that is distinct from said first sheet feeding means and that is adapted to feed a second plurality of sheets to said folding rollers along a second feed line,

characterised in that

upstream of said sheet feeding section one sheet supply section is provided for unwinding and conveying a single web of paper according to a feeding direction, in that one cutting section is provided that is adapted to cut said web of paper, coming from said feeding direction, into sheets of paper having a determined length L, and in that a means is provided for distributing alternatively, and selectively, said sheets of paper to said first sheet feeding means for creating said first plurality of sheets and to said second sheet feeding means for creating said second plurality of sheets.

2. Folding and stacking machine, according to claim 1, wherein said means for distributing alternatively the sheets of paper between said first and said second sheet feeding means is arranged in said cutting section.

3. Folding and stacking machine, according to claim 1, wherein said cutting section comprises a cutting roller that has as input said web and as output said sheets, said means for distributing alternatively said sheets of paper between said first and said second means for moving comprising:

a first hold means for holding said sheets on a first angular portion of the surface of said cutting roller,

second hold means for holding alternately said sheets on a second angular portion of the surface of said cutting roller, such that when said second hold means holds said sheets on said second angular portion a sheet it supplied to said second plurality of sheets on said second feed line, whereas when said second hold means does not hold said sheets on said second angular portion a sheet is supplied to said first plurality of sheets on said first feed line.

4. Folding and stacking machine, according to claim 1, wherein said first angular portion extends substantially from a point downstream of said cutting means up to a tangent point between said cutting roller and the first roller of said first feed line, whereas the second angular portion extends substantially from said tangent point between said cutting roller and said first roller of said first feed line and a tangent point between said cutting roller and said second roller of said second feed line.

5. Folding and stacking machine, according to claim 1, wherein said cutting roller comprises a plurality of holes, said first hold means comprising a first suction means that is adapted to pneumatically connect said holes with a vacuum system at said first angular portion of said roller, for holding said sheets on said first angular portion, and said second hold means comprising a second suction means that is adapted to selectively connect said suction holes with said vacuum system at said second angular portion of said roller, for holding selectively on said second angular portion only sheets that have to form said second plurality of sheets.

6. Folding and stacking machine, according to claim 1, wherein, furthermore, a means is provided to create a path-length difference between the path of the second feed line and the path of the first feed line, said path-length difference being such that the sheets of the first and second pluralities of sheets reach the folding section according to a determined configuration.

7. Folding and stacking machine, according to claim 6, wherein said means to create a path-length difference comprises at least one phase reset roller in at least one among said first and said second sheet feeding means.

8. Folding and stacking machine, according to claim 7, wherein said, or each, phase reset roller is adapted to extend the path of said second feed line with respect to said first feed line for a length Δ

L that is equal to half sheet, or equal to an odd multiple of half sheet.

9. Folding and stacking machine, according to claim 1, wherein said first and said second feed lines comprise each a first portion in which said sheets are brought to a first speed V₁ and a second portion that is downstream of said first portion in which said sheets are brought to a second speed V_P, with V_P<

V₁.

10. Folding and stacking machine, according to claim 9, wherein said sheet feeding section comprises a first speed deceleration roller in said first feeding means, said first speed deceleration roller adapted to decelerate the feeding speed of said first plurality of sheets from V₁ to V_P before they reach said first folding roller and a second speed deceleration roller in said second feed line, said second speed deceleration roller adapted to decelerate the feeding speed of the second plurality of sheets from V₁ to V_P before they reach the second folding roller.

11. Folding and stacking machine, according to claim 1, wherein said linear speed of said speed deceleration roller is equal to a half of the linear speed of said transfer roller.

12. Folding and stacking machine, according to claim 1, wherein said supply speed of said web is double with respect to the linear speed of said folding rollers V_P.

13. Folding and stacking machine, according to claim 1, wherein a first actuating means is provided that is adapted to selectively start/stop said first sheet feeding means and a second actuating means is provided that is adapted to selectively start/stop said second sheet feeding means and a drive unit being provided, said drive unit adapted to operate said actuating means between a first and a second configuration, in such a way that:

in said first configuration said actuating means of said second feed line are stopped and said machine operates in a multi-fold way, interfolded or not interfolded, with sheets that are fed only through said first feed line;

in said second configuration said second actuating means is operated so that the sheets of said first plurality and the sheets of said second plurality reach from the respective feed lines a point of confluence, so that said machine operates in a single-fold way.

14. Folding and stacking machine, according to claim 13, wherein, in said first operative condition said speed deceleration roller acts as “

overlap”

roller, and therefore according to a ratio X between the speed V₁ upstream of the speed deceleration roller and the speed V_P downstream of the speed deceleration roller, a corresponding portion Y of the length L of a sheet 11 being overlapped to a next sheet 11′

obtaining a determined interfolded configuration.

15. Folding and stacking machine,

according to claim 13, wherein, in said first operative condition said first feeding speed V₁ has a ratio X₁ with respect to the folding speed V_P, said ratio selected from the group comprised of:

X₁=3/2, for Z-type folded sheets with one interfolded panel;

X₁=4/2, for W-type folded sheets with two interfolded panels;

X₁=5/4 for five panel folded sheets with one interfolded panel;

X₁=6/3, for six panel folded sheets with three interfolded panels;

X₁=6/4 for six panel folded sheets with two interfolded panels.

16. Folding and stacking machine, according to claim 1, wherein said folding section is independently removable as a unit with respect to said cutting section, said folding section comprising at least two folding rollers and being replaceable with an equivalent unit.

17. Folding and stacking machine, according to claim 7, wherein said phase reset roller is independently removable as a unit in order to change the length of the sheet, the width of the sheet, the folding configuration.

18. Folding and stacking machine, according to claim 1, wherein said folding and stacking machine has a support frame for supporting the cutting roller, the folding rollers, the transfer rollers etc., and the removable portion of the folding section is independently removable as a unit from the support frame of the machine, so that the folding rollers are removed as a unit, or as two sub-unities, and can be replaced with an equivalent portion, wherein said, or each, unit or modular portion comprises also the supports of the rollers and the transmission parts, already set with respect to one another.

19. Folding and stacking machine, according to claim 1, wherein said folding section has a left speed deceleration roller and a left folding roller that are removable independently from said frame as a left modular portion, and a right speed deceleration roller and a right folding roller that are removable independently from said frame as a right modular portion, said left and right modular portions being replaceable with equivalent portions, comprising any motion transmission means, all movable at said speed VP, whereby for adjusting the diameter of said folding rollers it is possible to change said folding section and said overlap rollers.

20. Folding and stacking machine, according to claim 1, wherein said phase reset roller can be replaced with a modular equivalent portion, but of different diameter in order to obtain a different delay of the sheets of the second feed line.