Vacuum conveyor

Abstract

Vacuum conveyor and process for transporting at least a portion of a material web in a web travel direction. The vacuum conveyor includes a suction box is positioned within a loop having a conveyor run adapted to contact and guide the material web and a return run moving in a direction opposite the conveyor run. The suction box includes a suction opening positioned adjacent the conveyor run to suction the material web onto the conveyor belt and an exhaust opening positioned adjacent the return run. A vacuum source is coupled to the exhaust opening through the return run. The process includes creating a suction air flow through the return run of the conveyor belt and suctioning at least a portion of the material web onto the conveying run.

What is claimed:  
     
         1 . A vacuum conveyor for guiding at least a portion of a running web into a machine for one of producing, finishing, or processing the web, comprising: 
 two rotatably mounted pulleys;    an air-pervious endless conveyor belt tensioned over said two pulleys to form a loop including a conveying run and a return run;    a vacuum source; and    a suction box located in the loop of said conveyor belt which is coupled to said vacuum source through an air flow path, such that a vacuum propagates through said conveying run to suction the web to be guided onto said conveyor belt,    wherein said air flow path is arranged through said return run of said conveyor belt.    
     
     
         2 . The vacuum conveyor in accordance with  claim 1 , wherein the at least a portion of the running web comprises a threading tail.  
     
     
         3 . The vacuum conveyor in accordance with  claim 2 , wherein the web comprises one of a paper and board web, and 
 wherein at least one of said two pulleys is a driven pulley.    
     
     
         4 . A process for conveying at least a portion of a material web with an apparatus that includes two rotatably mounted pulleys, an air-pervious endless conveyor belt tensioned over the two pulleys to form a loop including a conveying run and a return run, a vacuum source, and a suction box located in the loop of the conveyor belt, said process comprising: 
 creating a suction air flow from the vacuum source to the suction box through the return run of the conveyor belt;    suctioning the at least a portion of the material web onto a conveying run of an endless conveyor with a suction box having a suction opening positioned adjacent at least a portion of the conveying run; and    moving the endless conveyor to transport the at least a portion of the material web.    
     
     
         5 . The process in accordance with  claim 4 , further comprising blowing the at least a portion of the material web away from the conveying run at an end of the conveying run.  
     
     
         6 . The process in accordance with  claim 4 , wherein the at least a portion of the material web comprises a threading strip.  
     
     
         7 . The process in accordance with  claim 4 , wherein at least one of the two pulleys are driven by a motor, thereby moving the conveyor belt.