Patent ID: 9457600
Filing Date: 2016-10-04
CPC Classification: B41J,B65H

Claim Text:
1. A conveyance device comprising: an upstream roller that supplies a sheet medium to be processed to a conveyance path; a downstream roller that conveys the supplied medium to a processing position; at least two encoders respectively sensing the speed of the upstream and downstream rollers, and a conveyance control unit that is configured to convey the sheet medium at a target speed, V the conveyance control unit is further configured to change the target speed of the upstream roller to eliminate a conveyance difference, which is a difference between a length of media conveyed by the upstream roller and a length of media conveyed by the downstream roller from a start of a conveyance operation, based on the conveyance difference; wherein the conveyance control unit is configured to control the change of the target speed of the upstream roller and downstream roller by way of a proportional intergral derivative (PID) controller based on output from the at least two encoders, wherein the conveyance control unit is further configured to control the start time of driving the upstream roller to be before the start time of driving the downstream roller.