Patent ID: 7192020

Claim:
A sheet processing apparatus, comprising: sheet stacking means for stacking sheets; sheet processing means for processing the sheets stacked on the sheet stacking means; a sheet holding portion which stores supplied sheets while preceding sheets stacked on the sheet stacking means are processed by the sheet processing means; sheet conveying means for conveying the sheets stored in the sheet holding portion to the sheet stacking means in a conveying direction; an abutment stopper, provided in the sheet holding portion, against which the upstream edges of the supplied sheets abut; moving means for moving the supplied sheets in a direction opposite to the conveying direction to abut the upstream edges thereof against the abutment stopper; and a holding member which holds the supplied sheets in the sheet holding portion with their upstream edges abutted against the abutment stopper until the last sheet of the sheets to be stored is supplied in the sheet holding portion, wherein the sheet conveying means conveys the stored sheets to the sheet stacking means from the sheet holding portion when a downstream edge in the conveying direction of the last sheet of the sheets to be stored has projected from the downstream edges of the sheets held in the sheet holding portion by a predetermined amount.