Patent ID: 7367733
Filing Date: 2008-05-06
Classification: B41J,B65H

Abstract:
1. An apparatus for transporting a sheet medium, comprising: an entrance drive roller paired with a corresponding entrance pressure roller to form an entrance nip for transporting the sheet medium into a scanning section between the entrance nip and an exit nip; the exit nip formed by an exit drive roller paired with a corresponding exit pressure roller for transporting the sheet medium out from the scanning section; wherein, at each end of the entrance pressure roller, an entrance pressure roller actuation arm, actuated by a rotatable entrance roller cam, actuates the entrance pressure roller to exert a variable force against the entrance drive roller; and wherein, at each end of the exit pressure roller, an exit pressure roller actuation arm, actuated by a rotatable exit roller cam, actuates the exit pressure roller to exert a variable force against the exit drive roller, the apparatus further comprising a controller continuously determining a desired entrance nip pressure and a desired exit nip pressure as the sheet medium is transported from the entrance nip to the exit nip, and varying a force applied by at least one of the entrance nip and the exit nip based on the determined desired pressures.