Patent ID: 8929774
Filing Date: 2015-01-06
Classification: G03G

Abstract:
1. A belt unit detachably attachable to a housing of an image forming apparatus, the belt unit comprising: an endless belt stretched in a looped state having openings in its lateral sides; front and rear side plates between which the endless belt is disposed; and a holder comprising at least two belt supporters provided between the front and rear side plates within the loop of the endless belt to stretch and support the endless belt, the at least two belt supporters including: wherein the holder changes a state of tension of the endless belt by moving the at least one transfer roller between a first state and a second state, the first state allowing the endless belt to circulate for image formation, the second state allowing the belt unit to be detached from the housing, wherein the holder is configured to move the at least one transfer roller adjacent supporter independently of the at least one transfer roller and lift the opening in the endless belt to a prescribed position to expose it from the front side plate in a third state, the third state enabling detachment and attachment of the at least one transfer roller to and from the loop of the endless belt.