Electrophotography-based additive manufacturing system with transfer-medium service loops

An additive manufacturing system for printing a three-dimensional part using electrophotography, the additive manufacturing system comprising:

• a rotatable photoconductor component having a surface configured to receive layers of at least one material using electrophotography;
• a rotatable transfer medium configured to travel through a first region to receive the layers from the rotatable photoconductor component, and further configured to travel through a second region to transfer the received layers;
• a platen configured to receive the transferred layers from the rotatable transfer medium in the second region in a layer-by-layer manner to print the three-dimensional part from at least a portion of the received layers from the rotatable transfer medium;
• and
• a plurality of service loops configured to move a first portion of the rotatable transfer medium through the first region at a constant rate line speed, and further configured to move a second portion of the rotatable transfer medium through the second region at an intermittent line speed.

A method for printing a three-dimensional part, the method comprising:

• rotating a transfer medium such that a first portion of the transfer medium in a first region moves at a first line speed, and such that a second portion of the transfer medium moves at a second line speed that is different from the first line speed;
• rotating a photoconductor component at a rate that is synchronized with the first line speed;
• developing layers of the three-dimensional part from a development station onto a surface of the rotating photoconductor component while the photoconductor component is rotating;
• transferring the developed layers from the rotating photoconductor component to the rotating transfer medium in the first region;
• and
• pressing the developed layers between the platen and a transfusion plate to transfer the developed layers from the rotating transfer medium to a platen in the second region.