Postprocessing apparatus and image forming apparatus

An image forming apparatus, comprising

• a postprocessing apparatus;
• wherein a print sheet after printing is supplied to the post processing apparatus;
• and
• the postprocessing apparatus comprises:
• a processing tray on which a print sheet as a target of a postprocess is put;
• a stopper guide with which the print sheet on the print sheet makes contact;
• an intermediate roller configured to transport the print sheet;
• a registration mechanism configured to move the incoming print sheet transported by the intermediate roller onto the processing tray and align print sheets on the processing tray;
• a guide mechanism configured to guide the print sheet moved by the registration mechanism toward the stopper guide;
• a driving device of the registration mechanism;
• a transmission mechanism configured to transmit driving force of the driving device to the guide mechanism with a delay;
• wherein the registration mechanism comprises a holder having a registration roller, and a first roller configured to make contact with the holder, rotate by the driving force of the driving device and swing the holder;
• the guide mechanism comprises a sheet contact member configured to make contact with an end of the print sheet, and a second roller configured to make contact with the sheet contact member, rotate by the transmission mechanism and swing the sheet contact member;
• and
• the transmission mechanism comprises a reduction roller configured to make a rotation angle of the second roller smaller than a rotation angle of the first roller.