Patent ID: 8226077

Claim:
A sheet processing method of a sheet processing apparatus including a stacker that holds a sheet bundle, an alignment roller that can come in contact with and be separated from a sheet surface of a sheet bundle held by the stacker, a stapler to perform a stapling process on the sheet bundle at a first position, folding portion to fold the sheet bundle and be located in a second position which is in a downward direction of the first position comprising: moving the sheet bundle to the first position; stapling the sheet bundle at the first position; causing the sheet bundle to come down from the first position to the second position by the stacker, after the stapling process is performed on the sheet bundle; causing the alignment roller to come in contact with the sheet bundle moved to a position lower than a specified position and to rotate at a peripheral speed higher than a movement speed of the stacker; bringing the rotating roller surface of the alignment roller into contact with the sheet bundle while the stapled sheet bundle is come down from the first position to the second position by the stacker; and folding the sheet bundle moved to the second position by the stacker.