Abstract: An improved automatic shutoff nozzle tip which is mounted on the downstream end of a nozzle body of an injection molding machine or the like who's purpose is to act as a passageway for molten plastic fluid allowing the fluid to flow in one direction when urged to open by the pressure created by the forward motion of the plasticizing screw of said molding machine and to close when said pressure is lower than the designed opening pressure. The nozzle, having an convex outwardly extended portion that mates up with a sprue bushing or mold having complimentary convex radii, said nozzle having a orifice on the distal end that mates with a complimentary orifice of said sprue bushing. A nozzle that has a means for attachment to a nozzle body or the like with a rear seat, poppet and spring or similar device who's poppet is normally in the closed position until pressure is applied urging the poppet to move in the downstream direction and providing for a passageway for molten plastic fluid.

Abstract: An improved precise control non-return valve assembly which is mounted on the front end of a helical rotating plasticating screw of an injection molding machine or the like that is surrounded by a heated elongated barrel and end-cap that forms a distribution chamber, whose purpose is to allow means for passage of molten plastic fluid in the downstream direction while preventing it in the opposite direction. The valve having an outwardly extended portion of a shaft and has a means to accept a ring that is sandwiched between a bushing assembly and a rear seating area. The bushing assembly consists of at least two bushings and one pin whose dual purpose is to govern the forward movement of the ring and to absorb the force that is being applied to it. The non-return valve assembly when moved forward with the screw, forms a seal, builds pressure, and displaces molten plastic fluid from the distribution chamber through a discharge chamber passageway and into a mold.

Abstract: An improved positive control non-return valve assembly which is mounted on the front end of a helical plasticating screw of an injection molding machine. The valve assembly comprises a thread retainer with means for attachment to the plasticating screw. The valve assembly also comprises a distribution chamber that has an annular shaped flow gap and a cylindrical passageway that leads to a plurality of discharge ports. The non-return valve assembly forms a seal, builds pressure, and displaces molten plastic fluid from the distribution chamber through a discharge chamber passageway, and into a mold.