Patent ID: 7954802

Claim:
A discharging and stacking method of a sheet post-processing apparatus which stacks a sheet on a process tray, stacks the sheet discharged from the process tray on a storage tray, and rotates a paper discharge roller provided at the end of the process tray in a sheet discharging and conveying direction and a bundle discharge belt having a bundle hook for discharging and conveying the sheet in the storage tray direction so as to discharge the sheet to the storage tray, wherein the sheet is conveyed in the state where a first tangential speed at which the paper discharge roller conveys the sheet in the storage tray direction and a first movement speed of the bundle hook are identical with each other, and during a sheet stacking operation in which the bundle hook passes from the discharge start position to the sheet rear end contacting member of the process tray, wherein the paper discharge roller rotates at a second tangential speed slower than the first tangential speed and the bundle hook moves at a second movement speed slower than the second tangential speed until the bundle hook moves from a discharge start point to a discharge end position of the sheet during a sheet stacking operation in which the bundle hook passes from a discharge start position to a sheet rear end contacting member of the process tray, and wherein the paper discharge roller is stopped and the bundle hook moves at a third movement speed slower than the second movement speed after the bundle hook reaches the discharge end position.