Apparatus for the high-pressure cross-linking molding of polymers

Claim 1

A high-pressure fluid cross-linking molding apparatus for molding polymers, comprising: extruder means for melting and kneading a mixture composed of a polymer and a cross-linking agent by applying such temperature and pressure as will not give rise to a cross-linking reaction; a plurality of reaction units each having a reaction compartment and relatively movable reaction plunger therein, each said reaction compartment being adapted to receive therein the molten mixture from said extruder means, and said reaction unit each having means associated therewith for applying a higher temperature and pressure on said mixture than is applied by said extruder means for causing a cross-linking reaction to occur when said mixture is located within said reaction compartment; first passageway means providing communication between the discharge end of said extruder means and said reaction compartments, said first passageway means including a plurality of first passageways connecting and providing communication between each of said reaction compartments and the discharge end of said extruder means; a molding heaD assembly adapted for molding the cross-linked polymer; second passageway means providing communication between said reaction compartments and said molding head assembly, said second passageway means including a plurality of second passageways connected to and providing communication between each of said reaction compartments and said molding head assembly; transfer valve means associated with said first and second passageways for alternately opening and closing said first and second passageways to provide for the continuous flow from said reaction compartments to said molding head assembly while permitting intermittent and alternating flow from said extruder means to each of said reaction compartments; said transfer valve means including a shiftable valve member movable between first and second positions, said valve member when in said first position providing communication between said extruder means and one of said reaction compartments while isolating the other reaction compartment from said extruder means, said other reaction compartment being connected in communication with said molding head assembly when said valve member is in said first position; said valve member when in said second position providing direct communication between said other reaction compartment and said extruder means while isolating said one reaction compartment from said extruder means, said one reaction compartment being in communication with said molding head assembly when said valve member is in said second position; and said valve member when being shifted between said first and second positions totally disconnecting all of said reaction compartments from said extruder means, said valve member when being shifted between said first and second positions, at least when in an intermediate location disposed between said first and second positions, resulting in all of said reaction compartments being in communication with said molding head assembly.