Compressible nip rolls for multiribbon transport
View Patent ↗A folder superstructure includes a former, a first nip roll located downstream of the former and having a compressible outer layer, and a second nip roll forming a nip with the first nip roll. A nip roll for nipping a plurality of superimposed printed ribbons or webs is also disclosed, the nip roll including a roll body and a compressible layer disposed about the roll body. A method for operating a printing press is also provided.
1. A printing press comprising:
printing units printing on a web, the web being slit and formed into a ribbon bundle;
a former folding the printed ribbon bundle;
a first nip roll located downstream of the former and having a compressible outer layer; and
a second nip roll forming a nip with the first nip roll.
2. The printing press as recited in claim 1 wherein the second nip roll includes a second compressible outer layer.
3. The printing press as recited in claim 1 wherein at least one of the first and second nip rolls is driven.
4. The printing press as recited in claim 3 further comprising an individual drive motor connected to at least one of the first and second nip rolls.
5. The printing press as recited in claim 1 further comprising a second former and a third nip roll downstream of the second former, the third nip roll having a third compressible outer layer.
6. The printing press as recited in claim 1 wherein the compressible layer is made of a foamed material.
7. The printing press as recited in claim 1 wherein the compressible layer has a Poisson's ratio of 0.50 or less.
8. The printing press as recited in claim 1 wherein the compressible layer is made of urethane with gas inclusions.
9. The printing press as recited in claim 1 wherein the compressible layer is made of rubber with gas inclusions.
10. The printing press as recited in claim 1 further comprising an RTF.
11. The printing press as recited in claim 10 further comprising a pull roll upstream of the RTF.
12. The printing press as recited in claim 11 further comprising a gathering roll upstream of the RTF.
13. The printing press as recited in claim 2 wherein the second compressible outer layer is formed of urethane with gas inclusions or rubber with gas inclusions.
14. The printing press as recited in claim 8 wherein the urethane with gas inclusions has a hardness of 40 durometer and a Poisson's ratio of 0.35.
15. The printing press as recited in claim 6 wherein the second nip roll includes a second compressible outer layer made of foamed material.
16. The printing press as recited in claim 6 wherein the foamed material has a hardness of 40 durometer and a Poisson's ratio of 0.35.
17. A printing press comprising:
printing units printing on a web, the web being slit and formed into a ribbon bundle;
a former folding the printed ribbon bundle;
a first nip roll located downstream of the former and having a compressible outer layer;
a second nip roll forming a nip with the first nip roll; and
a second former and a third nip roll downstream of the second former, the third nip roll having a third compressible outer layer,
wherein the first nip roll and third nip roll share a common axle.