Process for alignment of sheet material on a reference edge

Abstract

The invention relates to a process for alignment of sheet material ( 1 ) which is processed in a machine which processes sheet material ( 1 ). To do this the sheet material ( 1 ) is aligned into one conveyor plane ( 9 ) laterally and with respect to its twisting ( 6 ) with reference to its conveyor direction ( 22 ). The position of the sheet material ( 1 ) in the conveyor plane ( 9 ) is always acquired at a point ( 35 ) on one side edge ( 24 ) of the sheet material with a position which is defined to the reference edge ( 23 ) of the sheet material ( 1 ).

1 . Process for alignment of sheet material ( 1 ) which is processed in a machine which processes sheet material ( 1 ), and is aligned thereto in one conveyor plane ( 9 ) laterally and with respect to its twisting ( 6 ) with reference to its conveyor direction ( 22 ), wherein the position of the sheet material ( 1 ) in the conveyor plane ( 9 ) is always acquired on each copy at a point ( 35 ) on one side edge ( 24 ) of the sheet material ( 1 ) with a position which is defined to the reference edge ( 23 ) of the sheet material ( 1 ).  
     
     
         2 . Process as claimed in  claim 1 , wherein a line sensor ( 30 ) is used to determine the position of the sheet material ( 1 ).  
     
     
         3 . Process as claimed in  claim 2 , wherein CCD lines ( 30 ) are used to determine the position of the sheet material ( 1 ).  
     
     
         4 . Process as claimed in  claim 2 , wherein diode lines are used to determine the position of the sheet material ( 1 ).  
     
     
         5 . Process as claimed in  claim 1 , wherein the sheet material ( 1 ) is further conveyed during its alignment in the conveyor direction ( 22 ).  
     
     
         6 . Process as claimed in  claim 1 , wherein the formats of the sheet material ( 1 ) which are to be variably processed and its cutting tolerances ( 39 ) do not influence the image position ( 37 ) by measuring the position of the sheet material ( 1 ) always at the same locations ( 35 ,  23 ).  
     
     
         7 . Process as claimed in  claim 1 , wherein the position of the operating points ( 40 , 41 ) which is dependent on the original error ( 39 ) of the sheet material ( 1 ) for activation of the lateral alignment elements ( 25 ,  27 ) is replaced by defined acquisition of the position ( 35 ,  23 ) of the sheet material ( 1 ).  
     
     
         8 . Process as claimed in  claim 7 , wherein the position  37  of the printed image is defined relative to the position of the sheet material ( 1 ) via reference distances ( 36 ,  38 ).  
     
     
         9 . Process as claimed in  claim 8 , wherein the first reference distance is formed by the distance of the printed image ( 37 ) from the reference edge ( 23 ) of the sheet material ( 1 ).  
     
     
         10 . Process as claimed in  claim 8 , wherein the second reference distance is formed by the distance of the printed image ( 37 ) from the reference point ( 35 ) of the side edge ( 24 ) of the sheet material ( 1 )>.