Sheet-handling device

A sheet-handling device comprising an intermediate tray, an intermediate conveyer passage for guiding a sheet into the intermediate tray, introduction rollers for introducing the sheet into the intermediate conveyer passage, conveying rollers for conveying, into the intermediate tray, the sheet introduced into the intermediate conveyer passage, a holder member for releasably holding the sheet introduced into the intermediate conveyer passage in a manner of being faced to the conveyer surface of the intermediate conveyer passage, holder member drive means for driving the holder member, introduction roller drive means for so driving the introduction rollers as to rotate forward, conveying roller drive means for so driving the conveying rollers as to rotate forward or reverse, and a controller for controlling the drive means;

• wherein, when a standby/overlap handling mode is set to select the number of pieces of sheets that are to stand by and are to overlap in the intermediate conveyer passage to be a predetermined number N which is equal to or more than three pieces to form a next sheaf of sheets following the preceding sheaf of sheets introduced into the intermediate tray, the controller so controls the drive means that:
• the introduction rollers and the conveying rollers are rotated forward so that a first sheet introduced into the intermediate conveyer passage is nipped at its leading end by the conveying rollers and is conveyed until the trailing end thereof separates away from the introduction rollers and, thereafter, the conveying rollers are halted;
• the conveying rollers are rotated forward for a second or subsequent sheet, except the N-th sheet, successively introduced by the introduction rollers into the intermediate conveyer passage when the leading end thereof has approached the nipping portion of the conveying rollers, so that the leading end is nipped by the conveying rollers and, after having conveyed the sheet until the trailing end separates away from the introduction rollers and passes through the holder portion of the holder member, the conveying rollers are halted, the holding by the holder member is released, the conveying rollers are rotated reverse, and the sheet is moved back while being held again by the holder member and is halted in a state where the leading end is nipped;
• and
• finally, an N-th sheet is introduced by the introduction rollers into the intermediate conveyer passage in a state where the (N−1)-th sheet is held by the holder member, and the conveying rollers are rotated forward when the leading end of the N-th sheet has approached a nipping portion of the conveying rollers, so that the leading end of the N-th sheet is nipped being overlapped on the (N−1)-th sheet that has been nipped already by the conveying rollers, and the sheets of the predetermined number N are conveyed in an overlapped manner into the intermediate tray.