Machine and Method for the Production of a Web of Fiber Material with an Increased Volume

Abstract

A machine for the production of a web of paper or other fiber material ( 1, 6, 17, 37 ), comprising a belt ( 14, 26, 43 ), wherein the length of the belt ( 14, 26, 43 ) is elastically extendable, the web of fiber material ( 1, 6, 17, 37 ) can be fed to the belt ( 14, 26, 43 ) when the belt ( 14, 26, 43 ) is in extended state and the belt ( 14, 26, 43 ) can be slackened when the web of fiber material ( 1, 6, 17, 37 ) is placed thereon, such that the web of fiber material ( 1, 6, 17, 37 ) is compressed and the adhesion forces between the web of fiber material ( 1, 6, 17, 37 ) and the belt ( 14, 26, 43 ) are sufficiently high in order to avoid the formation of folds in the compressed web ( 1, 6, 17, 37 ).

1 . A machine for producing a fibrous web of paper or some other material ( 1 ,  6 ,  7 ,  37 ) with a belt ( 14 ,  26 ,  43 ), characterized in that the belt ( 14 ,  26 ,  43 ) is elastically extensible longitudinally, it being possible for the fibrous web ( 1 ,  6 ,  17 ,  37 ) to be led to the belt ( 14 ,  26 ,  43 ) in its elongated condition after which the belt ( 14 ,  26 ,  43 ) with the superimposed fibrous web ( 1 ,  6 ,  17 ,  37 ) can be relaxed so that the fibrous web ( 1 ,  6 ,  17 ,  37 ) is compressed and the adhesive forces between the fibrous web ( 1 ,  6 ,  17 ,  37 ) and the belt ( 14 ,  26 ,  43 ) being sufficiently great that fold formation in the compressed fibrous web ( 1 ,  6 ,  17 ,  37 ) is prevented.  
   
   
       2 . The machine as claimed in  claim 1 , characterized in that the machine comprises at least one pressing section ( 8 ,  19 ,  38 ) with at least one press-nip ( 12 ,  13 ,  21 ,  22 ,  39 ,  40 ,  51 ) and that the belt ( 14 ,  26 ,  43 ) can be elongated in front of or during its passage through the first press-nip ( 21 ) and relaxed after passing through the last press-nip ( 22 ) and that the fibrous web ( 1 ,  6 ,  17 ,  37 ) and the belt ( 14 ,  26 ,  43 ) can be led together in front of or within the first press-nip ( 21 ).  
   
   
       3 . The machine as claimed in  claim 1 , characterized in that the machine comprises at least one pressing section ( 8 ,  19 ,  38 ) with at least one press-nip ( 12 ,  13 ,  21 ,  22 ,  39 ,  40 ) and that the belt ( 14 ,  26 ,  43 ) can be elongated in front of or during its passage through a press-nip ( 40 ,  51 ) and relaxed after passing through the same press-nip ( 40 ,  51 ) and that the fibrous web ( 1 ,  6 ,  17 ,  37 ) and the belt ( 14 ,  26 ,  43 ) can be led together in front of or within the press-nip ( 40 ,  51 ).  
   
   
       4 . The machine as claimed in  claim 1 , characterized in that a deflection roll ( 31 ,  44 ) is provided before the at least one press-nip ( 21 ,  22 ,  40 ) and this can be driven at a lower speed than the first press roller ( 23 ,  41 ) and the second press roller ( 20 ,  42 ).  
   
   
       5 . The machine as claimed in  claim 1 , characterized in that a deflection roll ( 32 ,  47 ) is provided after the at least one press-nip ( 21 ,  22 ,  40 ) and this can be driven at a lower speed than the first press roller ( 23 ,  41 ) and the second press roller ( 20 ,  42 ).  
   
   
       6 . The machine as claimed in  claim 1 , characterized in that after passing through the press-nip ( 12 ,  13 ,  21 ,  22 ,  39 ,  40 ,  51 ) the fibrous web ( 1 ,  6 ,  17 ,  37 ) led forward together with a belt can be transferred to a second belt running at a lower speed relative to the belt.  
   
   
       7 . The machine as claimed in  claim 6 , characterized in that the second belt is a transport belt to transfer the fibrous web ( 1 ,  6 ,  17 ,  37 ) to a third belt by means of which the fibrous web ( 1 ,  6 ,  17 ,  37 ) is led through a third press-nip.  
   
   
       8 . The machine as claimed in  claim 6 , characterized in that the second belt is a transport belt to transfer the fibrous web ( 1 ,  6 ,  17 ,  37 ) to a third belt by means of which the fibrous web ( 1 ,  6 ,  17 ,  37 ) can be led through a drying section following the pressing section.  
   
   
       9 . The machine as claimed in  claim 1 , characterized in that the belt ( 14 ,  26 ,  43 ) is a fabric, a felt or a transfer belt or a smoothing belt.  
   
   
       10 . A process for the production of a fibrous web of paper or some other material ( 1 ,  6 ,  17 ,  37 ) having the following steps: 
 the elongation of a belt ( 14 ,  26 ,  43 ) length-wise    the forward movement of a fibrous web ( 1 ,  6 ,  17 ,  37 ) on the belt ( 14 ,  26 ,  43 ) in its elongated condition    the relaxation of the belt ( 14 ,  26 ,  43 ) so that the fibrous web ( 1 ,  6 ,  17 ,  37 ) is compressed and    ensuring that the adhesive forces between the fibrous web ( 1 ,  6 ,  17 ,  37 ) and the belt ( 14 ,  26 ,  43 ) are sufficiently high that fold formation in the compressed fibrous web ( 1 ,  6 ,  17 ,  37 ) is avoided.    
   
   
       11 . A process for operating a machine as claimed in  claim 10 , characterized in that in order to smooth the fibrous web ( 1 ,  6 ,  17 ,  37 ) when it is transferred from the belt ( 14 ,  26 ,  43 ) the web is pressed against a succeeding transport belt.  
   
   
       12 . The process as claimed in  claim 10 , characterized in that the fibrous web ( 1 ,  6 ,  17 ,  37 ) is compressed by less than 5%.  
   
   
       13 . The process as claimed in  claim 10 , characterized in that the fibrous web ( 1 ,  6 ,  17 ,  37 ) is led forward with a dry-weight content of less than 60%.  
   
   
       14 . The process as claimed in  claim 10 , characterized in that the fibrous web ( 1 ,  6 ,  17 ,  37 ) is compressed by less than 3%.  
   
   
       15 . The process as claimed in  claim 10 , characterized in that the fibrous web ( 1 ,  6 ,  17 ,  37 ) is led forward with a dry-weight content of less than 40%.