PURPOSE: To prevent the generation of burst noise owing to jump collision of a paper material by a method wherein a tapered paper material guide means is disposed in a sheet material conveying direction extending from the upper stream sheet material conveyance regulating member side toward a space in which the resist loop of a sheet material is formed.

CONSTITUTION: Sheet materials P are conveyed by a conveyance roller 7 and a separation belt 8 in a state to be separated one by one. After the sheet material is guided by a separation regulating plate 23 and brought into contact with a guide member 24, it is nipped between resist roller pair 9a and 9b and conveyed to a turn-over sheet path (b). In which case, a sheet path part (a curvature path part) (a) is formed by a different guide member 25 positioned facing the guide member 24. In this case, the separation regulation plate 23 is formed as a sheet material guide means and protruded in the space of the sheet path part (a) and the forward end 23a thereof is formed in a taper-form state toward a sheet material conveying direction. This constitution prevents jump collision of the rear end part of the sheet material P with the guide member 24.