Sheet processing machine

Abstract

A sheet processing machine (10) has a device (44) for monitoring sheets (12) and a transfer mechanism (26) for moving sheets (12) along a handling direction within the sheet processing machine (10). The device (44) comprises a light emitting element forming a light barrier in a sheet passage between the light emitting element and the light receiving element. A control unit (46) is connected to the light receiving element and is adapted to register each sheet (12) passing the sheet passage.

1 . A sheet processing machine with a device for monitoring sheets and a transfer mechanism for moving the sheets along a handling direction within the sheet processing machine, the sheet processing machine comprising:
 the device comprising a light emitting element and a light receiving element assigned to the light emitting element forming a light barrier in a sheet passage between the light emitting element and the light receiving element, and   a control unit connected to the light receiving element and adapted to register each sheet passing the sheet passage,   wherein the control unit comprises a storage module for storing information about the sheets and/or the sheet processing machine, and   wherein a target shape of the sheets is stored in the storage module of the control unit.   
     
     
         2 . The sheet processing machine according to  claim 1 , wherein the light barrier formed in the sheet passage by the light emitting element and the light receiving element is a light curtain. 
     
     
         3 . The sheet processing machine according to  claim 2 , wherein the light curtain extends over at least 80% of a width of the sheet passage, especially over at least 90% of the width of the sheet passage. 
     
     
         4 . The sheet processing machine according to  claim 1 , wherein the light receiving element and the light emitting element are mounted on a first rail and a second rail, respectively. 
     
     
         5 . The sheet processing machine according to  claim 4 , wherein the first rail and the second rail are parallel to each other. 
     
     
         6 . The sheet processing machine according to  claim 1 , wherein an expected number of sheets is stored in the storage module of the control unit, the expected number being determined based on the number of sheets provided in a loading station of the sheet processing machine and/or the number of sheets taken from the loading station, and the control unit is adapted to compare a current number of sheets having passed the sheet passage with the expected number of sheets. 
     
     
         7 . The sheet processing machine according to  claim 1 , wherein the target shape of the sheets is determined based on a reference sheet being passed through the sheet passage. 
     
     
         8 . The sheet processing machine according to  claim 1 , wherein the target shape of the sheets is determined by the control unit based on a reference file transferred to the sheet processing machine from a remote computer. 
     
     
         9 . The sheet processing machine according to  claim 1 , wherein the target shape comprises a target size of the sheet and/or a target contour of the sheet. 
     
     
         10 . The sheet processing machine according to  claim 6 , wherein the sheet processing machine comprises a human-machine-interface connected to the control unit. 
     
     
         11 . The sheet processing machine according to  claim 10 , wherein the control unit is adapted to transmit a warning message to the human-machine-interface of the sheet processing machine if the current number of sheets is lower than the expected number of sheets, especially if there are no more sheets in the loading station. 
     
     
         12 . The sheet processing machine according to  claim 10 , wherein the control unit is adapted to transmit a warning message to the human-machine-interface if the target shape of at least one sheet is not matching the target shape. 
     
     
         13 . The sheet processing machine according to  claim 1 , wherein the device for monitoring sheets is arranged between a waste removal station and a blank separation station of the sheet processing machine. 
     
     
         14 . The sheet processing machine according to  claim 1 , wherein the sheets are made of paper, cardboard, foil or a composite material thereof.