Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
188 words
In an extruder of the type having an axially rotatable feed screw disposed within a feed cylinder and in which material is fed from a hopper through a hopper opening into the screw cylinder, and having a gear drive unit including a feed screw driving shaft to which the feed screw is detachably coupled and by which it is rotatably driven, the improvement comprising, a. a chamber between the end of the feed screw cylinder and the feed screw driving shaft of the gear drive unit, b. a gear drive unit feed screw driving shaft having a pressure sealed drive connection presenting into said chamber, c. a feed screw in a feed cylinder, said feed screw having a drive end which extends through a portion of said cylinder and through said chamber to a sealed drive connection with the gear unit feed screw driving shaft, said chamber being closed except for communication with the hopper opening through a small annular clearance between the feed screw drive end and the wall of the feed cylinder, and d. at least one conduit connection into said chamber from the exterior thereof.
Claim 2
Dependent Claim
188 words
In an extruder of the type having an axially rotatable feed screw disposed within a feed cylinder and in which material is fed from a hopper through a hopper opening into the screw cylinder, and having a gear drive unit including a feed screw driving shaft to which the feed screw is detachably coupled and by which it is rotatably driven, the improvement comprising, a. a chamber between the end of the feed screw cylinder and the feed screw driving shaft of the gear drive unit, b. a gear drive unit feed screw driving shaft having a pressure sealed drive connection presenting into said chamber, c. a feed screw in a feed cylinder, said feed screw having a drive end which extends through a portion of said cylinder and through said chamber to a sealed drive connection with the gear unit feed screw driving shaft, said chamber being closed except for communication with the hopper opening through a small annular clearance between the feed screw drive end and the wall of the feed cylinder, and d. at least one conduit connection into said chamber from the exterior thereof.
Claim 3
Dependent Claim
33 words
An extruder as described in claim 1 wherein the seal of said sealed drive connection between said feed screw drive end and said gear unit feed screw driving shaft is a wiper seal.
Claim 4
Dependent Claim
20 words
An extruder as described in claim 1 further including a vacuum pump connected to said at least one conduit connection.
Claim 5
Dependent Claim
38 words
An extruder as described in claim 1 further including a vacuum pump connected to said at least one conduit connection into said chamber, and a filter between said vacuum pump inlet and any material drawn through said chamber.
Claim 6
Dependent Claim
31 words
An extruder as described in claim 1 further including a vacuum pump connected to said at least one conduit connection, and means coupled to said chamber for measuring the chamber pressure.
Claim 7
Dependent Claim
28 words
An extruder as described in claim 1 further including a vacuum pump connected to said at least one conduit connection and a hermetic seal at the hopper top.
Claim 8
Dependent Claim
22 words
An extruder as described in claim 1 further including a pressurizing additive feed device connected to said at least one conduit connection.
Claim 9
Dependent Claim
33 words
An extruder as described in claim 1 further including a pressurizing additive feed device connected to said at least one conduit connection, and means coupled to said chamber for measuring the chamber pressure.
Claim 10
Dependent Claim
55 words
An extruder as described in claim 1 further including a pressurizing additive feed device connected to said at least one conduit connection including means for adjusting the pressure in said chamber to be higher than the pressure in the said annular clearance between said feed screw drive end and the wall of the feed cylinder.