Device for controlling or regulating the basis weight of a paper or cardboard web

Abstract

Device for controlling or regulating a basis weight of a web in a web manufacturing process of a web producing machine. The device includes a first control circuit, adapted to adjust the basis weight, that includes at least one adjustable device for influencing the basis weight and at least one basis weight sensor. A second control circuit having at least one sensor for detecting a concentration of incoming backwater is also provided. The instant abstract is neither intended to define the invention disclosed in this specification nor intended to limit the scope of the invention in any way.

What is claimed:  
     
         1 . A device for controlling or regulating a basis weight of a web in a web manufacturing process of a web producing machine, comprising: 
 a first control circuit, adapted to adjust the basis weight, comprising at least one adjustable device for influencing the basis weight and at least one basis weight sensor;    a second control circuit having at least one sensor for detecting a concentration of incoming backwater.    
     
     
         2 . The device according to  claim 1 , wherein said at least one device for influencing the basis weight comprises a plurality of adjustable elements which are arranged across a width of the machine.  
     
     
         3 . The device according to  claim 1 , wherein said at least one adjustable device for influencing the basis weight is an actuator for said second control circuit.  
     
     
         4 . The device according to  claim 1 , wherein said at least one sensor for detecting the concentration of the backwater is positioned one of before and in a backwater container.  
     
     
         5 . The device according to  claim 1 , wherein said at least one sensor for detecting the concentration of the backwater is positioned in a backwater supply to a headbox.  
     
     
         6 . The device according to  claim 1 , further comprising at least one actuator coupled to said at least one adjustable device, 
 wherein said second control circuit is coupled to said at least one actuator.    
     
     
         7 . The device according to  claim 1 , wherein said at least one basis weight sensor is located in a vicinity of a drying section.  
     
     
         8 . The device according to  claim 7 , wherein said at least one basis weight sensor is located at an end of the drying section.  
     
     
         9 . The device according to  claim 1 , wherein said at least one basis weight sensor is located between a press section and a drying section.  
     
     
         10 . The device according to  claim 9 , wherein said at least one basis weight sensor is located directly after the press section.  
     
     
         11 . The device according to  claim 1 , wherein the material web comprises one of a paper and cardboard web, and the machine is one of a paper and cardboard machine.  
     
     
         12 . An apparatus for controlling or regulating a basis weight of a web in a web manufacturing process of a web producing machine, comprising: 
 a first control circuit;    at least one adjustment element coupled to said first control circuit adapted to adjust the basis weight of the web;    at least one basis weight sensor coupled to said first control circuit adapted to measure the basis weight, wherein said first control unit controls said at least one adjustment device in accordance with a measured basis weight;    a second control circuit;    at least one sensor adapted for detecting a concentration of incoming backwater, wherein said second control circuit is adapted to adjust the basis weight in accordance with the detected concentration.    
     
     
         13 . The apparatus according to  claim 12 , further comprising a headbox having a stock inlet; 
 a backwater supply coupled to said stock inlet, wherein said at least one adjustment element is coupled to said backwater supply, and wherein said second control circuit is coupled to said at least one adjustment device.    
     
     
         14 . The apparatus according to  claim 13 , wherein said at least one adjustment element comprises a backwater adjustment element and a stock adjustment element, 
 wherein said first control circuit and said second control circuit are each coupled to said backwater adjustment element and said stock adjustment element.    
     
     
         15 . The apparatus according to  claim 12 , further comprising a headbox having a stock inlet with a stock inlet control; 
 a backwater supply coupled to said stock inlet with a backwater supply control,    wherein said at least one adjustment element is coupled to said stock inlet and,    wherein said second control circuit is coupled to said backwater supply control and to said stock inlet control.    
     
     
         16 . The apparatus according to  claim 12 , further comprising a headbox having a stock inlet having a first stock inlet adjustment element and a second stock inlet adjustment element; 
 a backwater supply coupled to said stock inlet,    wherein said at least one adjustment element is coupled to said backwater supply, and    wherein said first control circuit is further coupled to said second stock inlet adjustment element, and said second control circuit is coupled to said at least one adjustment device and to said first stock inlet adjustment element.