Patent ID: 8596630

Claim:
A sheet processing apparatus that flattens a curved folded spine which is a bent portion of a folded sheet bundle formed by folding sheets stacked one upon another, comprising: a conveyance unit configured to convey the sheet bundle to a flattening position at which flattening of the folded spine of the sheet bundle is performed; a flattening unit configured to press the folded spine of the sheet bundle positioned at the flattening position to thereby flatten the folded spine; a holding unit provided independently of said conveyance unit and configured to hold the sheet bundle such that the sheet bundle is not moved when said flattening unit performs flattening; and a control unit configured to stop a driving signal for driving said conveyance unit when the sheet bundle is conveyed to a predetermined location upstream of the flattening position in a conveying direction of the sheet bundle, and hold the sheet bundle with said holding unit before the conveyance of the sheet bundle is stopped, to thereby stop the sheet bundle at the flattening position.