Patent ID: 7588241

Claim:
A sheet processing apparatus connected to an image forming apparatus that forms images corresponding to a set operation mode on sheets, comprising: a first stacking section that stacks sheets; a curved inversion path that inverts the sheets; a sheet feed section that feeds the sheets stacked in said first stacking section in one of a first sheet feed mode in which sheets are fed after being inverted by said inversion path and a second sheet feed mode in which sheets are fed without passing through said inversion path; a conveying section that conveys the sheets fed by said sheet feed section and the sheets with the images formed thereon; a second stacking section that stacks the conveyed sheets; a sheet processing section that performs predetermined processing on the sheets stacked in said second stacking section; a setting section that sets sheet information about the sheets stacked in said first stacking section; a determining section that determines whether a predetermined information is included in the set sheet information; a display section that displays a predetermined message when the predetermined information is included in the set sheet information; and an inhibiting section that inhibits the inversion of the sheets by said inversion path when the predetermined information is included in the set sheet information.