Patent ID: 7080831

Claim:
A sheet sorting apparatus comprising: a stacking tray for stacking sheets formed with images; a processing tray for temporarily stacking sheets in a process leading to the stacking tray; a first path for discharging the sheets to the stacking tray without temporarily stacking the sheets on the processing tray; a second path for discharging the sheets to the stacking tray after discharged sheets are temporarily stacked on the processing tray; shifting means for shifting the sheets stacked on the processing tray to change a stacking position of the sheets stacked on the stacking tray via the first path and the sheets stacked on the stacking tray via the second path; capacity recognition means for recognizing whether a stacking limit of the processing tray is exceeded by detecting a volume of the sheets temporarily stacked on the processing tray; and wherein an action for discharging from the first path directly to the stacking tray, and an action for shifting a sheet bundle and discharging from the second path to the stacking tray are performed according to each sorting sheet count information, when sheet sorting is specified; means for discharging the sheets thus far temporarily stacked on the processing tray to the stacking tray, activating the shifting means so that the stacking of subsequent sheets is possible at the same stacking position on the stacking tray as the sheets just discharged from the processing tray until a predetermined number of sheets specified by sheet-sorting count information is reached, and discharging the subsequent temporarily stacked sheets from the processing tray when the predetermined number of sheets is reached, when the capacity recognition means recognizes that a stacking limit of the processing tray has been exceeded when temporarily stacking the sheets in the processing tray in the second path; wherein a sheet bundle discharged from the processing tray when the sheet-sorting count is reached and at least a first sheet of sheets discharged from the first path are overlapped and discharged to the stacking tray.