Abstract: An image forming apparatus having a cleaning mechanism for cleaning paper powder or toner pressed and remaining on the surface of the circumference of an endless belt is provided. The cleaning mechanism includes a rotational shaft part that is detachably and rotatably attached to a supporting frame. The supporting frame of the cleaning mechanism is turned with the rotation of the rotational shaft part so that the supporting frame of the cleaning mechanism faces the belt supporting frame, fixing both frames at a point where a cleaning member presses the surface of the circumference of the endless belt.

Abstract: An on-line system having a plurality of terminal equipments and host computers connectable to the terminal equipments, each host computer responsive to a job request from a terminal equipment being provided with an on-line process for transferring the control of the job request to a job execution process determined in accordance with the content of the job request, and a plurality of regular job execution processes for executing, if the job request is a regular job request, a regular job for the regular job request. The on-line control process is provided with an irregular job execution process space generating process for generating an irregular job execution process space for the irregular job execution.