Post-processing device

A post-processing device comprising:

• a discharge port through which a sheet is discharged;
• an intermediate tray on which the sheets are stacked to form a bundle of the sheets, the intermediate tray disposed on an upstream side of the discharge port in a conveyance direction of the sheet and below the discharge port;
• a discharge tray on which the sheet and the bundle of sheets discharged through the discharge port are stacked, the discharge tray disposed on a downstream side of the discharge port in the conveyance direction and below the discharge port;
• and
• an air sending part which sends an air to the sheet and the bundle of sheets to cool the sheet and the bundle of sheets,
• wherein the air sending part includes:
• an upper air sending member which generates a downward air flow from above the discharge port;
• an upper switching member distributable the air flow generated by the upper air sending member to above the intermediate tray and to above the discharge tray;
• a lower air sending member which generates an upward air flow from below the discharge port;
• a lower switching member distributable the air flow generated by the lower air sending member to below the intermediate tray and to above the discharge tray;
• and
• a controller which controls the upper switching member and the lower switching member.