Perforation device
The present invention relates to perforation device for the manufacture of a perforated nonwoven material, whereby a prebonded nonwoven with embossing points is guided to a nonwoven perforation device, needles of a needle roller engage into the prebonded nonwoven and perforate it, and the perforated nonwoven material then undergoes further processing. A ratio is set between the number of needles to the number of embossed points of between 0.15 and 0.25 and a ratio of hole size to embossed point size of between 0.15 and 0.25.
1. A perforation device for perforating a nonwoven material, comprising at least one needle roller and a counter-roller having a peripheral surface, wherein the needle roller and the counter-roller from a gap through which a nonwoven material is conducted for the purpose of perforation, wherein the needle roller has a number of needles of between 10 needles/cm 2 and 25 needles/cm 2 , and wherein the needles have at least in part a circular diameter, have an effective needle diameter of between 1.5 mm and 2.5 mm, and a needle area component of the surface of the needle roller of between 35% and 65%.
2. The perforation device of claim 1 , wherein the needle roller and the counter-roller are mounted so that the needles of the needle roller engage the peripheral surface of the counter-roller.
3. The perforation device of claim 2 , wherein the peripheral surface of the counter-roller is made of a material that yields to the needles.
4. The perforation device of claim 3 , wherein the peripheral surface comprises a felt material.
5. The perforation device of claim 1 , additionally including an unwinder positioned adjacent the needle roller and counter-roller for receiving a roll of nonwoven material.
6. The perforation device of claim 5 , including rolls positioned adjacent the unwinder and said rollers for guiding the nonwoven material from the unwinder to said rollers.
7. The perforation device of claim 6 , wherein said rolls include a tension measuring roll positioned for engaging the nonwoven material in its path of travel from the unwinder to said rollers and operable for measuring tension.
8. The perforation device of claim 7 , additionally including guide rolls positioned between the unwinder and said rollers for guiding the nonwoven material in its path of travel.
9. The perforation device of claim 6 , wherein said rolls are oriented for directing the nonwoven material onto the peripheral surface of the counter-roller and partially around the counter roller before the nonwoven material enters said gap between the needle roller and the counter-roller.
10. The perforation device of claim 9 , wherein the nonwoven material loops around the counter-roller through an arc greater than 45 degrees.
11. The perforation device of claim 1 , including rolls adjacent the needle roller and oriented for directing the nonwoven material to remain on the needle roller for a certain looping range after emerging from said gap.
12. The perforation device of claim 11 , wherein the rolls are oriented so that the nonwoven material remains on the needle roller through an arc of greater than 45 degrees.
13. The perforation device of claim 12 , wherein the rolls are oriented so that the nonwoven material remains on the needle roller through a range of 90 to 270 degrees.
14. The perforation device of claim 11 , wherein the rolls include a tension measuring roll.
15. The perforation device of claim 14 , wherein the rolls additionally include at least one guide roll.
16. The perforation device of claim 15 including a winder for receiving the perforated nonwoven material from said at least one guide roll and for winding the material into the form of a roll.