Kneading apparatus and method for kneading rubber-based composition using the same

Abstract

A kneading apparatus includes a barrel having a cylindrical chamber; a screw assembly rotating in the chamber so that a material to be kneaded is extruded in the axial direction by the rotation, the screw assembly including a screw section having helical blades and a kneading blade section in order to allow the material to flow into the clearance between the inner wall of the chamber and the kneading blade section, and to apply shearing forces to the material; a metering feeder for feeding the material at a substantially constant volumetric or gravimetric rate into the chamber; an injecting device for injecting a heat-removing medium into the chamber; and a discharging device for separating the heat-removing medium from the material and discharging the heat-removing medium from the chamber. A kneading method using the kneading apparatus is also disclosed.

1 . A kneading apparatus comprising: 
 a barrel having a cylindrical chamber;    a screw assembly rotating in the chamber for extruding a material to be kneaded in the axial direction, said screw assembly comprising a screw section having helical blades and a kneading blade section for allowing the material to flow into the clearance between the inner wall of the chamber and a kneading blade of said kneading blade section, and for applying shearing forces to the material to be kneaded;    a metering feeder for feeding the material at a substantially constant volumetric rate or at a substantially constant gravimetric rate from a feed port provided on the barrel into the chamber;    an injecting device provided on the barrel for injecting a heat-removing liquid medium into a first portion of the chamber; and    a discharging device including a reduced pressure producing device for separating the heat-removing medium from the material at a second portion of the chamber downstream from the first portion; and    means for densely filling the material to be kneaded at positions adjacent the second portion of the chamber, and for sealing the second portion of the chamber such that said reduced pressure producing device can provide a reduced pressure at said second portion.    
   
   
       2 - 10 . (canceled)  
   
   
       11 . The kneading apparatus according to  claim 1 , wherein said means for densely filling the material to be kneaded at positions adjacent the second portion of the chamber comprises an increased density of a pitch for the helical blades at positions adjacent the second portion of the chamber.  
   
   
       12 . The kneading apparatus according to  claim 1 , wherein said means for densely filling the material to be kneaded at positions adjacent the second portion of the chamber comprises helical blades or sheets capable of blocking the material to be kneaded.  
   
   
       13 . The kneading apparatus according to  claim 1 , wherein said means for densely filling the material to be kneaded at positions adjacent the second portion of the chamber comprises reverse flighted screws.  
   
   
       14 . The kneading apparatus according to  claim 1 , wherein said means for densely filling the material to be kneaded at positions adjacent the second portion of the chamber comprises rotors or kneading disks as return segments.