Injection molding method and apparatus

A method of injection molding comprising:

• transmitting, by a screw auger, a material along a barrel, the barrel having an interior with a longitudinal axis, the screw auger positioned within the barrel interior, the screw auger being substantially concentric with the barrel, the screw auger being operable to rotate, and the screw auger including a bore also substantially aligned with the longitudinal axis;
• heating, by a plurality of heating elements, the material within the barrel, the plurality of heating elements being in thermal communication with the barrel and capable of heating the material to a flowable state;
• transmitting, to a channel and by the screw auger, the material, the material being in a flowable state;
• receiving, by an injection chamber and from the channel, the material, wherein the channel provides fluid communication between the injection chamber and the barrel;
• urging, by a plunger, the material in the injection chamber into an injection tube, wherein the plunger is substantially aligned for movement along the longitudinal axis and with the bore, wherein the plunger is substantially coaxial with the screw auger, and wherein the plunger is capable of translating along an axis of the plunger relative to the screw auger, wherein the plunger in a first position impedes fluid communication between the barrel and the injection chamber, wherein the plunger in a second position does not impede fluid communication between the barrel and the injection chamber;
• receiving by an injection tube, the material urged by the plunger, wherein the injection tube is in fluid communication with the injection chamber, and wherein the injection tube is located opposite the plunger;
• sensing, by a plurality of sensors, pressure and temperature;
• wherein at least one of the plurality of sensors is in communication with at least one of the barrel, the injection chamber, the injection tube;
• relating the rotation of the screw auger upon a first pressure reading obtained from a first pressure sensor and a second reading of a second pressure sensor, wherein the first reading is indicative of a force applied to the screw auger in a direction that is substantially along the longitudinal axis, and wherein the second reading is indicative of a pressure of the material when heated to at least a flowable state, said screw auger configured within said barrel in a manner that substantially prevents the plastic being conveyed therein from being sheared, with tolerances between said screw and said barrel being sufficient such that gaps between an inside diameter of said barrel and an outside diameter of said screw are small enough so that plastic pellets cannot be sheared therebetween;
• and
• forming a barrier by compacting pellets within said barrel to prevent melting plastic from flowing backward as said pellets travel toward a melting zone, the injection molding method performed without employing a valve that substantially prevents a flowback of melted plastic.