Sheet conveying apparatus and image forming apparatus having the same
AssigneeCanon Kabushiki Kaisha
InventorsKazuo Ohyama, Makoto Kashimura
Life of this patent
Estimating the term…
Abstract
To provide a sheet conveying apparatus of low cost and high durability and also to provide an image forming apparatus having the same. A sheet S1 is pinched and conveyed by a metal driving roller having roughness provide on its surface and a pinch roller coming in pressure contact with the driving roller and thereby driven to rotate. And the pinch roller is formed of synthetic resin, so that the pinch roller can be manufactured less costly and the durability of the same can be increased.
Claims19
A sheet conveying apparatus comprising a pair of conveying rollers for pinching and conveying a sheet by a driving roller having roughness provided on a surface thereof and a pinch roller coming in pressure contact with the driving roller and driven to rotate, wherein the pinch roller is formed of resin of which a main raw material is polyacetal, wherein the pinch roller is formed with a die, the die is parted in a longitudinal direction so that a parting line does not appear on a circumference of the pinch roller, an inside diameter of a portion of the die for forming the end portion near a core side of the pinch roller is smaller than an inside diameter of a portion of the die for forming the substantial center portion of the pinch roller, and is set in such a manner that scoring is not caused on the pinch roller by the die during a mold releasing operation in expectation of some percentage for shrinkage of the substantial center portion of the pinch roller during resin filling-cooling-releasing processes.
A sheet conveying apparatus comprising a pair of conveying rollers for pinching and conveying a sheet by a driving roller having roughness provided on a surface thereof and a pinch roller coming in pressure contact with the driving roller and driven to rotate, wherein the pinch roller is formed of resin of which a main raw material is polyacetal, wherein said pinch roller is formed with a die, the die is parted in a longitudinal direction so that a parting line does not appear on a circumference of the pinch roller, an inside diameter of a portion of the die for forming the end portion near a core side of the pinch roller is smaller than an inside diameter of the die for forming the substantial center portion of the pinch roller, and the substantial center portion of the pinch roller shrinks during resin filling—cooling—releasing processes in such a manner that the diameter of the substantial center portion of the pinch roller becomes smaller than the inside diameter of the die for forming the end portion near a core side of the pinch roller.
A sheet conveying apparatus comprising a pair of conveying rollers for pinching and conveying a sheet by a driving roller having roughness provided on a surface thereof and a pinch roller coming in pressure contact with the driving roller and driven to rotate, wherein the pinch roller is formed of resin, and wherein the pinch roller is formed with a die, the die is parted in a longitudinal direction so that a parting line does not appear on a circumference of the pinch roller, an inside diameter of a portion of the die for forming the end portion near a core side of the pinch roller is smaller than an inside diameter of a portion of the die for forming the substantial center portion of the pinch roller, and is set in such a manner that scoring is not caused on the pinch roller by the die during a mold releasing operation in expectation of some percentage for shrinkage of the substantial center portion of the pinch roller during resin filling-cooling-releasing processes.
Dependencies are inferred from the claim text.