摘要:
A transfer belt is driven by a plurality of supporting rollers. A unit frame supports the supporting rollers in a rotatable manner. At least one of the supporting rollers includes a cylindrical member having a substantially same outer diameter over an entire length thereof. Each end portion of the cylindrical member in a longitudinal direction is supported by the unit frame via a bearing in a rotatable manner.
摘要:
A belt driving controller includes a driving roller having a radius r1, a plurality of driven rollers that is driven by rotation of the driving roller, the driven rollers having a radius r2, an endless belt that is wound on the driving roller and the driven rollers and an encoder that is attached to one of the driven rollers, and that outputs a signal. The rotation of the driving roller is controlled based on the signal from the encoder, and (α2/α1)×(r1/r2)≦1 is satisfied where α1 is a correction coefficient for a fluctuation in thickness of the endless belt caused by a belt winding angle on the driving roller, and α2 is a correction coefficient for a fluctuation in the thickness on the driven roller.
摘要:
In an image forming apparatus, a developing unit for forming an image by use of a two-ingredient type developer, i.e., toner and carrier mixture, includes a container for replenishing fresh toner and for replacing carrier deteriorated due to aging or a developer including such carrier. The developer in the developing unit will be collected based on the number of times that a part of the developer has been replenished.