Device for decurling a sheet of paper taken from a roll
View Patent ↗The invention is directed to a roll assembly comprising an elongated, substantially rigid, cylindrical roll; a carrier sheet wrapped around the roll, having an inner edge attached to the roll in parallel with the roll axis and upper and lower surfaces with opposed longitudinal edges extending perpendicularly to the roll axis; and a friction strip extending along each longitudinal edge of the upper surface of the carrier sheet, wherein the coefficient of friction of the strips is greater than the coefficient of friction of the upper surface of the carrier sheet. The carrier sheet attached to the roll is preferable a plastic film made of polyester or polycarbonate having a thickness in the range of 5 to 15 mils. This sheet may be made up of one film sheet or multiple sheets. Soft, tacky, rubber friction strips are attached along the longitudinal edges of the upper surface of the sheet and can be is from approximately ½ inch to 2 inches in width and approximately 10 to 30 mils in thickness running for substantially the entire length of the film carrier sheet.
1. A roll assembly for decurling a printed graphic, comprising:
an elongated, substantially rigid, cylindrical roll;
a carrier sheet wrapped around the roll, having an inner edge attached to the roll in parallel with the roll axis and upper and lower surfaces with opposed longitudinal edges extending perpendicularly to the roll axis and defining a sheet length such that when unwrapped with the lower surface of the sheet overlying a flat work surface, the sheet extends transversely to the roll axis at least about ten times the roll diameter; and
a friction strip permanently carried by and extending along each longitudinal edge of the upper surface of the carrier sheet, wherein the coefficient of friction of the strips is greater than the coefficient of friction of the upper surface of the carrier sheet.
2. The roll assembly of claim 1 , wherein the carrier sheet is plastic or paper.
3. The roll assembly of claim 1 , wherein the carrier sheet has a total thickness in the range of range of 5–30 mils.
4. The roll assembly of claim 1 , wherein the upper surface of the friction strips comprises rubbery material.
5. The roll assembly of claim 1 , wherein the upper surface of the friction strips comprises a foam material.
6. The roll assembly of claim 1 , in combination with a flat work surface having a lower coefficient of friction than the coefficient of friction of the lower surface of the carrier sheet, whereby the roll assembly may be manually rotated without displacement, on the work surface.
7. The roll assembly of claim 1 , wherein the friction strips project above the upper surface of the sheet, a distance in the range of about 10–30 mils.
8. The roll assembly of claim 1 , including a plurality of slide strips having an upper surface attached to the lower surface of the carrier sheet, wherein the slide strips have a lower surface with a coefficient of friction that is less than the coefficient of friction of the lower surface of the carrier sheet.
9. The roll assembly of claim 1 , wherein the roll is a metal tube.
10. The roll assembly of claim 1 , wherein the roll is a plastic tube.
11. The roll assembly of claim 1 , wherein the roll is a paper tube.
12. The roll assembly of claim 1 , wherein the roll is a solid cylinder.
13. The roll assembly of claim 1 , wherein the carrier sheet is a composite of laminated sheets of different materials.
14. The roll assembly of claim 13 , wherein the upper surface of the composite sheet has a higher coefficient of friction than the lower surface of the composite sheet.
15. A roll assembly for decurling a printed graphic, comprising:
a cylindrical roll having a nominal diameter in the range of about ½ inch to 3 inches and an axial length greater than said nominal diameter;
a sheet wrapped around the roll, having an inner edge attached to the roll in parallel with the roll axis and upper and lower surfaces with opposed longitudinal edges defining a sheet length such that when unwrapped, the sheet extends transversely to the roll axis at least about ten times the roll diameter; and
a friction strip permanently carried by and extending along each longitudinal edge of the sheet, wherein the strips have an upper surface with a coefficient of friction that is greater than the coefficient of friction of the upper surface of the carrier sheet.
16. The roll assembly of claim 15 , further including a printed graphic rolled and fully entrapped within the wrapped sheet of the roll assembly.
17. A roll assembly for decurling a printed graphic, comprising:
an elongated, substantially rigid, cylindrical roll;
a sheet wrapped around the roll, having an inner edge attached to the roll in parallel with the roll axis and upper and lower surfaces with opposed longitudinal edges extending perpendicularly to the roll axis and defining a sheet length such that when unwrapped with the lower surface of the sheet overlying a flat work surface, the sheet extends transversely to the roll axis at least about ten times the roll diameter; and
a friction strip permanently carried by and extending along each longitudinal edge of the upper surface of the carrier sheet, wherein the friction strip projects a height in the range of about 10–30 mm from the upper surface of the sheet.
18. The roll assembly of claim 17 , wherein the coefficient of friction of the strips is greater than the coefficient of friction of the upper surface of the sheet.
19. The roll assembly of claim 18 , further including a printed graphic rolled and fully entrapped within the wrapped sheet of the roll assembly.
20. The roll assembly of claim 17 , further including a printed graphic rolled and fully entrapped within the wrapped sheet of the roll assembly.