Plasticizing device for extrusion or injection molding

• US 3,310,837 A
• Filed: 08/24/1965
• Issued: 03/28/1967
• Est. Priority Date: 12/06/1961
• Status: Expired due to Term

• Current Assignee: Ludwig Wittrock
• Original Assignee: Ludwig Wittrock
• Inventors: LUDWIG WITTROCK
• Application Number:
  US04/482,215
• Time in Patent Office: 581 Days
• US Class Current: 366/76.1
• CPC Class Codes: B29C 45/50 Axially movable screw
• CPC Class Codes: B29C 48/03 characterised by the shape of the extruded material at extrusion
• CPC Class Codes: B29C 48/40 using two or more parallel screws or at least two parallel non-intermeshing screws, e.g. twin screw extruders
• CPC Class Codes: B29C 48/435 Sub-screws
• CPC Class Codes: B29C 48/44 Planetary screws
• CPC Class Codes: B29C 48/45 Axially movable screws

Claims

1. A PLASTICIZING AND FEEDING DEVICE FOR THE DISCHARGE OF MOLDABLE PLASTIC MATERIAL, COMPRISING A GENERALLY CYLINDRICAL HOUSING WITH AN INLET FOR SAID MATERIAL AND A OUTLET THEREFOR, SAID HOUSING BEING PROVIDED WITH INTERNAL TEETH FORMING A HELICAL THREAD THEREON BETWEEN SAID INLET AND SAID OUTLET, A CENTRAL FEED SCREW WITH A PERIPHERAL HELICAL THREAD MATCHING THAT OF SAID HOUSING, A PLURALITY OF PLANETARY FEED SCREWS WITH COMPLEMENTARY HELICAL THREADS MATINGLY ENGAGING THE THREADS OF SAID CENTRAL FEED SCREW AND SAID HOUSING, SAID PLANETARY FEED SCREWS BEING DISPOSED IN AN ANNULAR CLEARANCE BETWEEN SAID CENTRAL FEED SCREW AND SAID HOUSING WITH PERIPHERAL SPACING FROM ONE ANOTHER, DRIVE MEANS FOR ROTATING SAID CENTRAL FEED SCREW, A PLURALITY OF SPACER BARS OCCUPYING THE SPACES BETWEEN ADJOINING PLANETARY FEED SCREWS OVER AT LEAST PART OF THEIR LENGTH FOR SUBSTANTIALLY BLOCKING THE FLOW OF SAID MATERIAL THROUGH SAID SPACES EXCEPT BY WAY OF HELICAL CHANNELS DEFINED BY SAID THREADS UPON ROTATION