Three stage intermixing feed screw for polymers

A polymer-extruder screw comprising:

• a screw channel bounded by a screw core as a channel bottom and a main flight as channel walls forming screw flights extending radially outward from the screw core in helical progression intermediate a screw shank on a proximal end and a discharge tip on a distal end of an extruder screw,
• a mixing section in which the screw channel has a designed mixing depth in a direction perpendicularly to the screw core and a designed mixing width between helical walls of the main flight for receiving and mixing a desired quantity of material between the screw shank and a transition section of the extruder screw,
• a transition section having progressively shallower screw channels with the screw core having a progressively larger diameter extending helically from the mixing section of the extruder screw,
• a metering section having a plurality of at least three pressure channels juxtaposed helically between helical rotations of the main flight and extending from the transition section to the discharge tip of the extruder screw,
• channel interruptions of the pressure channels,
• the channel interruptions being comprised of helical slopes extending inward radially on opposite helical sides of interruption tops,
• the interruption tops having constancy of radii from an axis of the extruder screw,
• pressure-channel bottoms that are offset helically from the interruption tops as designed for effective plastication of different polymers and other substances,
• pressure-channel flights on edges of the pressure channels which are adjacent to other pressure channels between the screw flights,
• the pressure-channel flights taper away helically to radii equal to the radii of the interruption tops from positions where the interruption-channel bottoms of the pressure channels approach the interruption tops,
• the helical slopes are adjusted in steepness to position the interruption tops adjacent to desired depths of adjacent pressure channels, and
• the constancy of the radii of the interruption tops is complete and uniform for a desired length of constant-radii tops.

A polymer-extruder screw comprising:

• a screw channel bounded by a screw core as a channel bottom and a main flight as channel walls forming screw flights extending radially outward from the screw core in helical progression intermediate a screw shank on a proximal end and a discharge tip on a distal end of an extruder screw,
• a mixing section in which the screw channel has a designed mixing depth in a direction perpendicularly to the screw core and a designed mixing width between helical walls of the main flight for receiving and mixing a desired quantity of material between the screw shank and a transition section of the extruder screw,
• a transition section having progressively shallower screw channels with the screw core having a progressively larger diameter extending helically from the mixing section of the extruder screw,
• a metering section having three pressure channels juxtaposed helically between the screw flights and extending from the transition section to a distal end of the extruder screw,
• channel interruptions of the pressure channels,
• the channel interruptions being comprised of helical slopes extending inward radially on opposite helical sides of interruption tops,
• the interruption tops having constancy of radii from an axis of the extruder screw,
• the three pressure channels are juxtaposed with interruption tops of a center pressure channel being offset helically from the interruption tops of side pressure channels successively in helical progression,
• pressure-channel bottoms that are offset helically from the interruption tops as designed for effective plastication of different polymers and other substances,
• pressure-channel flights on edges of the pressure channels which are adjacent to other pressure channels between the screw flights,
• the pressure-channel flights taper away helically to radii equal to the radii of the interruption tops from positions where the interruption-channel bottoms of the pressure channels approach the interruption tops,
• the helical slopes are adjusted in steepness to position the interruption tops adjacent to desired depths of adjacent pressure channels, and
• the constancy of the radii of the interruption tops is complete and uniform for a desired length of constant-radii tops.