Patent ID: 7758033

Claim:
A sheet post-processing apparatus comprising: a processing mechanism that beats down an end of a sheet by a paddle which is arranged at a position where the sheet has been dropped when the sheet is dropped and supplied to a standby tray, and performs post-processing for a sheet discharged from an image forming apparatus; a sheet discharge tray which is arranged on a downstream side with respect to the processing mechanism and loads the sheet discharged from the image forming apparatus; a detection mechanism that detects whether the sheet has been placed or not on the sheet discharge tray; and a control mechanism that controls discharging a sheet to the sheet discharge tray so that when there is no sheet on the sheet discharge tray detected by the detection mechanism, one sheet of the sheet bundle is discharged to the sheet discharged tray and then the sheet bundle is discharged in a bundle from the processing mechanism onto the sheet discharge tray.