Method and apparatus for correcting running state and tension for an endless belt in an image-forming apparatus

Abstract

An image-forming apparatus adjusts the running state of a belt by displacing one of the rolls supporting an endless belt, wherein the roll is displaced to prevent the belt from being twisted by a change in the tension of the endless belt that stems from the operation for displacing the roll. When the image-forming apparatus is provided with a belt running adjusting mechanism 20 which adjusts the running state of the endless belt 21 by displacing one (drive roll 22) of plural rolls supporting the belt 21 in the adjusting directions J, K, there is provided a tension correction mechanism 60 which corrects a change in the tension of the endless belt 21 that is caused by the operation of the belt running adjusting mechanism 20 for displacing the roll 22, by displacing, in the correction directions L, M, a contact member (tension roll 25) which is in contact with the belt 21 along the direction of width thereof.

Dependencies are inferred from the claim text.