Large sheet folder including sheet securing means

Claim 2

A large sheet folder having means for effecting a plurality of folds comprising: a table having a flat surface adapted to support a spreadout sheet, said surface having an elongated aperture formed centrally therein; means on opposite sides of said aperture for securing said sheet in a spreadout position on said surface for inspection, said securing means being adapted to engage the surface of said sheet inwardly of the edges thereof; means for folding said sheet positioned below said aperture; and means for moving said sheet through said aperture into said fold means with an intermediate portion of said sheet leading.

Claim 3

A sheet folder as set forth in claim 1 wherein said means for securing said sheet in a spreadout position comprises means for engaging sheets spread out on said table in the areas of the corners of such sheets.

Claim 4

A sheet folder as set forth in claim 1 wherein said means for securing said sheet in a spreadout position comprises means forming small apertures on said table and means for applying suction through said small apertures whereby a sheet positioned over said apertures will be restrained against movement by said suction.

Claim 5

A sheet folder as set forth in claim 1 wherein said means for folding said sheet comprises: means for effecting a plurality of longitudinal folds including four parallel rolls extending longitudinally of said aperture with two of said rolls forming a first nip line below and aligned with said aperture to receive sheets passing through said aperture and to effect a first longitudinal fold, the other two of said rolls positioned below and lateral of said first nip line with the plane passing through the axis of said other two rolls nonparallel with the plane passing through the axis of said first two rolls, one of said first two rolls and one of said second two rolls positioned to form a second nip line therebetween, said other two rolls positioned to form a third nip line therebetween; means for sequentially moving an intermediate double thickness portion of a sheet moving downwardly from said first nip line laterally into said second nip line and thence at least a double thickness portion of a sheet moving from said second nip line downwardly into said third nip line; means for effecting a plurality of crossfolds subsequent to said longitudinal folds; and means for guiding said sheet toward said cross folding means from said third nip line, said guide means comprising an endless belt wrapped about one of said second two rolls so that said belt first passes about a selected peripheral portion of said third roll and then about a selected peripheral portion of said fourth roLl, said belt having a portion thereof disposed between and along a tangent to one of said second two rolls, said portion of said belt passing through said third nip line and between said second two rolls, said belt and said fourth roll being adapted to receive and grip said sheet therebetween said belt leaving said fourth roll tangentially and at least laterally in a direction toward said cross folding means to advance said longitudinally folded sheet to said cross folding means.

Claim 6

A sheet folder as set forth in claim 1 including; means for effecting a plurality of longitudinal folds including four parallel rolls extending longitudinally of said aperture with two of said rolls forming a first nip line below and aligned with said aperture to receive sheets passing through said aperture to effect a first longitudinal fold, the other two of said rolls positioned below and lateral of said first nip line with the plane passing through the axis of said other two rolls nonparallel with the plane passing through the axis of said first two rolls, one of said first two rolls and one of said second two rolls, one of said first two rolls and one of said second two rolls positioned to form a second nip line therebetween, said other two rolls positioned to form a third nip line therebetween; means for sequentially moving an intermediate double thickness portion of a sheet moving downwardly from said first nip line laterally into said second nip line and thence at least a double thickness portion of said sheet moving from said second nip line downwardly into said third nip line; means for effecting a plurality of crossfolds subsequent to said longitudinal folds; means for guiding said sheet from said third nip line to said cross folding means; conveyor means comprising a plurality of endless belts extending perpendicular to said four rolls and positioned therebelow for receiving said longitudinally folded sheet; five cross folding rolls journaled for rotation on axes perpendicular to the axes of said four parallel rolls, three of said rolls being positioned adjacent to one another to form a first cross nip line between a first and second cross folding roll and a second cross nip line between said second and third cross folding roll, a fourth and fifth cross folding roll positioned to form a third cross nip line, said fourth and fifth cross folding rolls and said third nip line defined therebetween being disposed in a location substantially remote from said first, second and third cross folding rolls; means for guiding a sheet moving from said first cross nip line laterally to said second cross nip line; means for guiding a sheet at least laterally from said second cross nip line to said third remote cross nip line; and means for receiving said sheet as it moves from said third cross nip line.

Claim 7

A sheet folder as set forth in claim 5 having a plurality of endless conveyor belts interengaging said second and third cross folding rolls for guiding said sheet downwardly from said third cross folding roll, a plurality of laterally extending endless belts positioned below said third cross folding roll and adapted to receive a sheet from said third cross folding roll and convey it to said fourth and fifth cross folding roll.

Claim 8

A sheet folder as set forth in claim 6 having conveyor means for receiving a cross folded sheet from said third cross nip line with said conveyor means extending parallel to said conveyor belts interengaging said second and third cross folding rolls.