Patent ID: 8682233

Claim:
An apparatus to reduce registration errors in a marking device, the apparatus comprising: a transfer belt having a lateral edge, the transfer belt moving in a process direction across a transfer zone; an edge sensor to detect lateral positions of the lateral edge as the lateral edge passes the edge sensor; and a steering actuator including a belt steering roll having a longitudinal axis of rotation that is angularly adjustable in order to laterally shift a position to control lateral movement of the transfer belt along an axial extent of the axis of rotation of the belt steering roll, the belt steering roll rotatably mounted maintaining rolling engagement with the transfer belt, adjustments to lateral positions of the transfer belt by the steering actuator inducing a lateral shift profile to the lateral edge, the lateral shift profile defined by changes to the lateral positions of the lateral edge during a period in response to a change in angle of the longitudinal axis of the belt steering roll, the belt steering roll angle being adjusted based on a differential between a currently detected lateral position of a segment of the lateral edge and a predetermined lateral position derived from the lateral shift profile.