Process line cascade steering control

Abstract

Disclosed is a steering control system/method for a process line running a web material including at least two steering units, a downstream and an upstream steering unit. At least one controller is in communication with the downstream and upstream steering unit. The downstream steering unit collects downstream data concerning a downstream position of the web material and sends the downstream data to the controller. The upstream steering unit collects upstream data concerning an upstream position of the web material, and sends the upstream data to the controller. The data may be an actual position of the web material or a position of a frame or a roller of the steering unit. The controller utilizes the downstream data to effect a downstream adjustment of the downstream steering unit. The controller utilizes the downstream data and the upstream data to effect an upstream adjustment of the upstream steering unit.

1 . A steering control system for a continuous process line running a web material, comprising: 
 at least two steering units including a downstream steering unit and an upstream steering unit; and    at least one controller in communication with the downstream steering unit and the upstream steering unit,    wherein the downstream steering unit collects downstream data concerning a downstream position of the web material and sends the downstream data to the at least one controller,    the upstream steering unit collects upstream data concerning an upstream position of the web material and sends the upstream data to the at least one controller,    the at least one controller utilizes the downstream data to effect a downstream adjustment of the downstream steering unit, and    the at least one controller utilizes the downstream data and the upstream data to effect an upstream adjustment of the upstream steering unit.    
     
     
         2 . The steering control system of  claim 1 , wherein the controller is a programmable logic controller.  
     
     
         3 . The steering control system of  claim 1 , wherein: 
 the downstream steering unit includes a downstream steering assembly and a downstream measurement device,    the downstream measurement device is in communication with the controller,    the upstream steering unit includes an upstream steering assembly and an upstream measurement device, and    the upstream measurement device is in communication with the controller.    
     
     
         4 . The steering control system of  claim 3 , wherein: 
 the downstream measurement device is located proximate the downstream steering assembly,    the upstream measurement device is located proximate the upstream steering assembly,    the downstream data is a measurement of how far from a center of the process line the web material is running near the downstream steering assembly, and    the upstream data is a measurement of how far from the center of the process line the web material is running near the upstream steering assembly.    
     
     
         5 . The steering control system of  claim 1 , wherein: 
 the downstream steering assembly includes a downstream frame and a downstream roll, the downstream frame is pivotable in relation to a center of the process line, and the downstream roll is stationary in relation to the downstream frame,    the downstream adjustment of the downstream steering unit causes the downstream frame to pivot,    the upstream steering assembly includes an upstream frame and an upstream roll, the upstream frame is pivotable in relation to the center of the process line, and the upstream roll is stationary in relation to the upstream frame, and    the upstream adjustment of the upstream steering unit causes the upstream frame to pivot.    
     
     
         6 . The steering control system of  claim 1 , further including at least three steering units, wherein: 
 one of the at least three steering units is a downstream steering unit,    one of the at least three steering units is an upstream steering unit, and    remaining ones of the at least three steering units are both downstream and upstream steering units.    
     
     
         7 . The steering control system of  claim 6 , wherein when one of the remaining ones is acting as a downstream unit, the one sends downstream data to an immediate previous one of the remaining ones.  
     
     
         8 . The steering control system of  claim 6 , wherein when one of the remaining ones is acting as a downstream unit, the one sends downstream data to all previous ones of the remaining ones.  
     
     
         9 . The steering control system of  claim 1 , wherein the downstream data is a position of the web within the process line.  
     
     
         10 . The steering control system of  claim 5 , wherein the downstream data is a position of the downstream frame.  
     
     
         11 . The steering control system of  claim 5 , wherein the downstream data is a position of the downstream roller.  
     
     
         12 . The steering control system of  claim 1 , wherein the upstream data, is a position of the web within the process line.  
     
     
         13 . The steering control system of  claim 5 , wherein the upstream data is a position of the upstream frame.  
     
     
         14 . The steering control system of  claim 5 , wherein the upstream data is a position of the upstream roller.  
     
     
         15 . The steering control system of  claim 1 , wherein: 
 the at least one controller includes a downstream controller associated with the downstream steering unit and an upstream controller associated with the upstream steering unit,    the downstream steering unit receives the downstream data, and    the upstream steering unit receives the downstream data and the upstream data.    
     
     
         16 . A method for steering a web material through a continuous process line including at least a downstream steering unit and an upstream steering unit, comprising the steps of: 
 measuring a downstream position of the web material near the downstream steering unit, the downstream position being in relation to a center of the process line,    measuring an upstream position of the web material near the upstream steering unit, the upstream position being in relation to the center of the process line,    determining a downstream adjustment to be made to the downstream steering unit based on the downstream position,    determining an upstream adjustment to be made to the upstream steering unit based on the downstream position and the upstream position,    moving the downstream steering unit according to the downstream adjustment, and    moving the upstream steering unit according to the upstream adjustment.    
     
     
         17 . The method for steering a web material of  claim 16 , wherein moving the upstream steering unit does not align a center of the web material with the center of the process line at the upstream steering assembly.  
     
     
         18 . The method for steering a web material of  claim 16 , wherein: 
 moving the downstream steering unit includes the step of pivoting a downstream steering assembly, and    moving the upstream steering unit includes the step of pivoting an upstream steering assembly.