A method of controlling discharge of printed sheets, which makes it possible to acquire a desired number of printed sheets as a sheet bundle. A controller determines whether or not printed sheets are stored in the stacker. The controller detects the number of printed sheets stored in the stacker. A controller causes the stored printed sheets to be discharged from the stacker as a sheet bundle when the number of printed sheets stored in the stacker is equal to a desired sheet count set by a user. In a case where the set desired sheet count has been changed, if it is determined that the printed sheets are stored in the stacker, the controller causes the printed sheets stored in the sheet discharge unit to be discharged from the stacker.

A stacker includes a placement part that stacks thereon sheets discharged from a discharge port by a conveyor that conveys the sheets; a side guide that regulates edges of the sheets in a width direction intersecting a discharge direction of the sheets; a guide driver that moves the side guide along the width direction; and a controller configured to control the guide driver to position the side guide at a position where the sheet discharged from the discharge port is supported from below by the side guide.

A system for stacking a fanfolded continuous web of sheet material of indefinite length, such as corrugated cardboard, includes a feeding device that guides the continuous web longitudinally, a creasing device downstream of the feeding device to form transverse creases on the continuous web with a constant longitudinal pitch to define a succession of adjacent partitions, a folding device downstream of the creasing device for progressively and alternately fanfolding adjacent partitions along the creases, and a collection device for collecting the folded web. The collection device includes a vertical column for retaining the stack of fanfolded adjacent partitions, and a cutting unit is mounted at the top of the column to act on the fly on the top adjacent partition of the stack while tracking stack-formation without stopping the folding device. A method of stacking a sheet material, such as a fanfolded continuous web of corrugated cardboard of indefinite length.

A machine for producing packages of folded or interfolded laminar products made of paper, in particular packages of napkins, tissues, towels, or similar products, comprising a folding or interfolding group, equipped with a first and a second folding or interfolding roll configured to fold or interfold a plurality of sheets of paper, and to obtain a stack of folded or interfolded sheets, according to a predetermined folding or interfolding configuration, which grows in height along a vertical forming direction. The machine comprises, furthermore, a separation group configured to separate a completed stack of folded or interfolded sheets, once that a predetermined height of said stack being formed is reached, from a following stack being formed. A transfer group is, furthermore, provided configured to transfer the completed stack on a discharge device configured to discharge the completed stack from the machine.