Abstract Additive for plastic material and others being screw extruded, such as colorant, anti-oxidant and the like, is auger fed through the sidewall of the feed hopper just above the screw with the auger feed tube hooded by the upper side extending beyond the lower side and with the lower side terminating at a point in a range of distance along an approximately horizontal line extending from the in-feed sidewall, i.e., the sidewall where the auger feed tube penetrates, and substantially passing through the vertical axis of the feed hopper, and, at a distance from said axis towards said in-feed sidewall equal to about one-seventh the diameter of the hopper at that level to a distance from said axis away from said in-feed sidewall equal to about one-tenth diameter, but preferably within a distance from about one-ninth diameter from the axis towards the in-feed sidewall to about onefifteenth diameter beyond said axis, and most preferably between the said axis and about one-twelfth diameter therefrom toward the in-feed sidewall. Two or three auger tubes that substantially meet at a common point may be used to add a like number of additives simultaneously. Each hooded end may have any of various shapes from flat bevelled to arcuate to stepped. The motor drive for the screw extruder and the variable speed motor drive of the auger tube or tubes are controlled from a common electrical or other control device switch for coordinate proportional addition of additive.
The method of homogenously mixing an additive with a granular material during the screw extrusion thereof which comprises: by means of an auger feed tube having a hooded terminus metering the additive material horizontally into the feed hopper of the screw extruder above and adjacent the screw and delivering the additive from the hooded terminus of the tube at a point within about onetwelfth of the diameter distance from the vertical axis of the hopper, said diameter being of the hopper section at the auger feed tube level; and controlling the auger and the screw with a common switch whereby the operations thereof are coordinated.
Claim 2
Independent Claim
105 words
The method of homogenously mixing an additive with a granular material during the screw extrusion thereof which comprises: by means of an auger feed tube having a hooded terminus metering the additive material horizontally into the feed hopper of the screw extruder above and adjacent the screw and delivering the additive from the hooded terminus of the tube at a point within about onetwelfth of the diameter distance from the vertical axis of the hopper, said diameter being of the hopper section at the auger feed tube level; and controlling the auger and the screw with a common switch whereby the operations thereof are coordinated.
Claim 3
Dependent Claim
13 words
The method of claim 1, wherein said granular material is a plastic material.
Claim 4
Dependent Claim
12 words
The method of claim 1, wherein said granular material is thermoplastic material.