Patent ID: 7172186

Claim:
A sheet stacking apparatus comprising: a sheet transport path for transporting a sheet, discharge means disposed at the sheet transport path for transporting the sheet, a support tray disposed adjacent to the discharge means for temporarily supporting at least a part of the sheet transported by the discharge means, a stacker disposed at a downstream side of the support tray in a sheet moving direction for stacking and storing the sheet transported from the support tray, a sheet pushing member disposed adjacent to the support tray and having a touching member protruding above the support tray for abutting against a trailing edge of the sheet stacked on the support tray, and drive means capable of rotating in forward and reverse directions, said drive means including a belt member with the sheet pushing member attached thereto for reciprocally moving the sheet pushing member between a retracted position at an upstream side of a stacking position where the sheet is stacked on the support tray and a transport position at a downstream side of the stacking position, and a drive motor attached to the belt member and moving the sheet pushing member from the retracted position to the transport position and returning the sheet pushing member in a reverse direction from the transport position to the retracted position, said sheet pushing member having a posture at the transport position so that the sheet transferred onto the stacker is pressed between the stacker and the sheet pushing member.