Sheet feeding apparatus, particularly for rotary printing machines

Sheet feeding apparatus to feed separate sheets from a stack (27) to a machine (3) particularly for combination with a sheet-fed rotary offset printing machine

• comprising the combination of cooperating means;
• sheet separating means (23) separating a single sheet from the stack (27);
• a set-up or alignment table (19) adjacent the machine (3);
• front edge alignment means (43) movably positioned on a forward location of the set-up or alignment table to provide for frontal alignment of the sheet positioned on said set-up table when the alignment means are in a sheet alignment position, and release of the sheet when the alignment means are moved to a release position;
• lateral edge alignment means (45) positioned at the side or lateral location of the set-up or alignment table (19) to provide for lateral alignment and guidance of a sheet positioned on said table;
• a sheet transport conveyor means (17, 33) located between said separating means (23) and the set-up or alignment table (19) and transporting separated sheets to the set-up table;
• means ensuring engagement of a sheet being transported on said transport means with the lateral alignment means (45) as the sheet is being transported on said sheet transport means, and prealignment of the sheet in advance of said set-up or alignment table (19) including
• means positioned in advance--in the direction of sheet transport--of the alignment table (19) imparting a drive movement on the sheet while the sheet is on said sheet transport conveyor means and having a vectorial direction transverse to the direction of movement of the sheet from the separating means to the front alignment means of the set-up or alignment table (19) by superimposing a drive force transverse to said direction of movement on the force exerted on the sheet by the sheet transport conveyor means to obtain a resulting force acting on the sheet which has a lateral component directed towards said lateral alignment means (45);
• drive means (47, 53, 55;
• 29, 39) including a variable speed transmission in driving connection with said sheet transport conveyor means, and coupled to the sheet separating means (23), to the movable front alignment means (43) and to the machine (3) to synchronize operation of the separating means, the sheet transport conveyor means and the movement of the front alignment means with the machine receiving the separated sheet;
• a lateral sheet moving mechanism (57) located on said set-up or alignment table (19) and operable to move a sheet positioned in engagement with said front alignment means (43) and laterally into engagement with said lateral alignment means (45);
• and selectively operable lock-out means (82) engageable with said lateral sheet moving mechanism (57) to selectively disable said lateral sheet moving mechanism and permit placement of a sheet being fed by said sheet transport conveyor means into engagement with said lateral alignment means (45) by said transverse drive movement imparting means.