Protective arrangement in web cutting

Abstract

A protective arrangement ( 37 ) for a cutting equipment ( 10 ) for dividing a continuous fiber web ( 7 ) is described, said cutting equipment being arranged in a board or paper machine and includes at least one cutting member ( 16 ) for cutting the fiber web ( 7 ). In accordance with the invention the protective arrangement includes an endless belt member ( 20 ) movably arranged and having a straight run ( 21 ) between the cutting equipment and the fiber web to screen off at least an essential part of the cutting equipment from fibers which are released from the fiber web during the cutting. It also includes one or more cleaning members ( 34, 35 ) at least one of which being arranged in connection to the outside of the belt member at a distance from the cutting member, to remove the portion of the released fibers being caught by the belt member. The invention also relates to a board or paper machine that has such a protective arrangement.

1 . A protective arrangement ( 37 ) for a cutting equipment ( 10 ) for dividing a continuous fiber web ( 7 ), said cutting equipment ( 10 ) being arranged in a board or paper machine for manufacturing said fiber web ( 7 ) and includes at least one cutting member ( 16 ) for cutting the fiber web ( 7 ), characterized in that it includes 
 an endless belt member ( 20 ) movably arranged and having a straight run ( 21 ) which is arranged between the cutting equipment ( 10 ) and the fiber web ( 7 ) to screen off at least an essential part of the cutting equipment ( 10 ) from fibers which are released from the fiber web ( 7 ) during the cutting, and    one or more cleaning members ( 34 ,  35 ) at least one of which being arranged in connection to the outside of the belt member ( 20 ) at a distance from said cutting member ( 16 ), to remove the portion of the released fibers being caught by the belt member ( 20 ).    
     
     
         2 . A protective arrangement as claimed in  claim 1 , characterized in that the belt member ( 20 ) comprises at least two parallel, endless belts ( 23 ,  24 ), each forming its part of said screening-off run ( 21 ) and in that the belts ( 23 ,  24 ) define a gap between them, at least when they pass the cutting member ( 16 ) in order to give free passage therefor.  
     
     
         3 . A protective arrangement as claimed in  claim 2 , characterized in that the belts ( 23 ,  24 ) are arranged to run around two common, parallel rolls ( 25 ,  26 ) arranged at a predetermined distance from each other.  
     
     
         4 . A protective arrangement as claimed in  claim 2  or  3 , characterized in that the belts are arranged to run at a distance from each other so that their edges facing each other define said gap between them within at least their screening-off run parts.  
     
     
         5 . A protective arrangement as claimed in any one of claims  2 - 4 , characterized in that said gap is 1-5 mm, preferably 2-3 mm larger than the thickness of the cutting member ( 16 ) measured perpendicularly to the parallel edges of the belts ( 23 ,  24 ).  
     
     
         6 . A protective arrangement as claimed in  claim 2 , characterized in that the two belts ( 23 ,  24 ) are arranged to overlap each other with their edge parts facing each other, and in that it includes a gap-opening element ( 36 ) arranged upstream of the cutting member ( 16 ), seen in the direction of movement of the belts ( 23 ,  24 ), and extending down/up between the edges of the belts ( 23 ,  24 ) facing each other in order to separate the belts ( 23 ,  24 ) upon passage of the cutting member ( 16 ) while forming said gap.  
     
     
         7 . A protective arrangement as claimed in  claim 6 , characterized in that said gap is converging and ceases a predetermined distance after the cutting member ( 16 ) seen in the direction of movement of the belts ( 23 ,  24 ).  
     
     
         8 . A protective arrangement as claimed in  claim 6 , characterized in that a gap-stabilizing element is arranged downstream of the cutting member ( 16 ), extending down/up between the edges of the belts ( 23 ,  24 ) facing each other in order to widen the gap so that it has a substantially constant width between the gap-opening element and the gap-stabilizing element, between which elements the gap extends.  
     
     
         9 . A protective arrangement as claimed in any one of claims  1 - 8 , characterized in that a cleaning member ( 35 ) is also arranged in connection to the inside of the belt member ( 20 ) at a distance from the cutting member ( 16 ), in order to remove fibers that are collecting on the inside of the belt member ( 20 ).  
     
     
         10 . A protective arrangement as claimed in any one of claims  1 - 9 , characterized in that the cutting equipment ( 10 ) includes at least one nozzle ( 11 ;  61 ) for delivering said cutting member ( 16 ) in the form of an air jet or water jet.  
     
     
         11 . A protective arrangement as claimed in any one of claims  1 - 10 , characterized in that the cutting equipment ( 10 ) is arranged for edge trimming the fiber web ( 7 ) with the aid of at least one cutting member ( 16 ) to obtain at least one trimming, and is stationary during the cutting operation.  
     
     
         12 . A protective arrangement as claimed in any one of claims  1 - 10 , characterized in that the cutting equipment ( 10 ) is movably arranged across the fiber web ( 7 ) between a resting position outside the fiber web and an active position above the fiber web for tail cutting the fiber web in order to provide a tail ( 60 ), and in that said belt member ( 20 ) is arranged to extend between at least said resting position and said active position for the cutting equipment ( 10 ) and to be activated simultaneously or substantially simultaneously with the activation of the cutting equipment ( 10 ).  
     
     
         13 . A board or paper machine for manufacturing a continuous fiber web ( 7 ), including at least one cutting equipment ( 10 ) for dividing the fiber web, including at least one cutting member ( 16 ) for cutting the fiber web ( 7 ), characterized in that it also includes a protective arrangement ( 37 ) that includes 
 an endless belt member ( 20 ) movably arranged and having a straight run ( 21 ) which is arranged between the cutting equipment ( 10 ) and the fiber web ( 7 ) to screen off at least an essential part of the cutting equipment ( 10 ) from fibers which are released from the fiber web ( 7 ) during the cutting, and    one or more cleaning members ( 34 ,  35 ) at least one of which being arranged in connection to the outside of the belt member ( 20 ) at a distance from said cutting member ( 16 ), to remove the portion of the released fibers being caught by the belt member ( 20 ).    
     
     
         14 . A board or paper machine as claimed in claim ( 13 ), characterized in that the belt member ( 20 ) comprises at least two parallel, endless belts ( 23 ,  24 ), each forming its part of said screening-off run ( 21 ) and in that the belts ( 23 ,  24 ) define a gap between them, at least when they pass the cutting member ( 16 ) in order to give free passage therefor.  
     
     
         15 . A board or paper machine as claimed in  claim 14 , characterized in that the belts ( 23 ,  24 ) are arranged to run around two common, parallel rolls ( 25 ,  26 ) arranged at a predetermined distance from each other.  
     
     
         16 . A board or paper machine as claimed in  claim 14  or  15 , characterized in that the belts are arranged to run at a distance from each other so that their edges facing each other define said gap between them within at least their screening-off run parts.  
     
     
         17 . A board or paper machine as claimed in any one of claims  14 - 16 , characterized in that said gap is 1-5 mm, preferably 2-3 mm larger than the thickness of the cutting member ( 16 ) measured perpendicularly to the parallel edges of the belts ( 23 ,  24 ).  
     
     
         18 . A board or paper machine as claimed in  claim 14 , characterized in that the two belts ( 23 ,  24 ) are arranged to overlap each other with their edge parts facing each other, and in that it includes a gap-opening element ( 36 ) arranged upstream of the cutting member ( 16 ), seen in the direction of movement of the belts ( 23 ,  24 ), and extending down/up between the edges of the belts ( 23 ,  24 ) facing each other in order to separate the belts ( 23 ,  24 ) upon passage of the cutting member ( 16 ) while forming said gap.  
     
     
         19 . A board or paper machine as claimed in  claim 18 , characterized in that said gap is converging and ceases a predetermined distance after the cutting member ( 16 ) seen in the direction of movement of the belts ( 23 ,  24 ).  
     
     
         20 . A board or paper machine as claimed in  claim 18 , characterized in that a gap-stabilizing element is arranged downstream of the cutting member ( 16 ), extending down/up between the edges of the belts ( 23 ,  24 ) facing each other in order to widen the gap so that it has a substantially constant width between the gap-opening element ( 36 ) and the gap-stabilizing element, between which elements the gap extends.  
     
     
         21 . A board or paper machine as claimed in any one of claims  13 - 20 , characterized in that a cleaning member ( 35 ) is also arranged in connection to the inside of the belt member ( 20 ) at a distance from the cutting member ( 16 ), in order to remove fibers that are collecting on the inside of the belt member ( 20 ).  
     
     
         22 . A board or paper machine as claimed in any one of claims  13 - 21 , characterized in that the cutting equipment ( 10 ) includes at least one nozzle ( 11 ;  61 ) for delivering said cutting member ( 16 ) in the form of an air jet or water jet.  
     
     
         23 . A board or paper machine as claimed in any one of claims  13 - 22 , characterized in that the cutting equipment ( 10 ) is arranged for edge trimming the fiber web ( 7 ) with the aid of at least one cutting member ( 16 ) to obtain at least one trimming, and is stationary during the cutting operation.  
     
     
         24 . A board or paper machine as claimed in any one of claims  13 - 22 , characterized in that the cutting equipment ( 10 ) is movably arranged across the fiber web ( 7 ) between a resting position outside the fiber web and an active position above the fiber web for tail cutting the fiber web in order to provide a tail ( 60 ), and in that said belt member ( 20 ) is arranged to extend between at least said resting position and said active position for the cutting equipment ( 10 ) and to be activated simultaneously or substantially simultaneously with the activation of the cutting equipment ( 10 ).