SLACK PREVENTING DEVICE FOR ENDLESS BELT

PURPOSE:To provide a slack preventing device for an endless belt which prevents non-uniformization of a conveyance speed, deformation of a belt surface, and lowering of image quality owing to the deformation by a method wherein a mechanism to prevent a slack in the shape of a taper wherein size is increased toward an end part is arranged to the end part on the non-drift side of at least the one of rollers. CONSTITUTION:A slack absorbing member 21 in the shape of a hollow truncated cone having a given length in an axial direction is fixed to the outer periphery of the end part on the non-drift side of the one of cylindrical rollers 12 and 13, for example, the roller 12. The slack absorbing member 21 is formed of a resilient member in the shape of a taper in cross section where thickness is gradually increased toward the end part on the non-drift side of the roller 12, the slack absorbing member being formed of rubber and soft resin. The outer peripheral surface of the slack absorbing member 21 is covered with a low friction film 22 formed of a material having a low friction factor between the inner peripheral surface of the belt 11 and the outer peripheral surface of the slack absorbing member. This constitution absorbs a slack on the slack side without disturbing drift movement, prevents lowering of image quality due to the slack, and reduces the cost of a device.