Injection molding apparatus
OwnerRobert F. Dray, SR.inventor
Life of this patent
Estimating the term…
Abstract
An injection molding apparatus has an injection cylinder in fluid communication with the mold, wherein movement of a piston within the cylinder injects a selected quantity of resin into the mold. A plasticizing unit includes a flighted screw rotating in a heated containment barrel for plasticizing resin the plasticizing unit in selective fluid communication with the injection cylinder for supplying the injection cylinder with plasticized resin. A conduit connects the plasticizing unit to the injection cylinder to communicate resin from the plasticizing unit to the injection cylinder.
Claims12
An injection molding apparatus for injecting resin into a mold, the apparatus comprising:
- an injection cylinder in fluid communication with the mold, wherein movement of a piston within the cylinder injects a selected quantity of resin into the mold;
- a plasticizing unit including a flighted screw rotating in a heated containment barrel for plasticizing resin the plasticizing unit in selective fluid communication with the injection cylinder for supplying the injection cylinder with plasticized resin;
- a conduit connecting the plasticizing unit to the injection cylinder to communicate resin from the plasticizing unit to the injection cylinder;
- a backpressure-prevention device associated with the injection cylinder to prevent pressure developed in the injection cylinder from acting on one of the conduit and plasticizing unit;
- a nozzle extending from the injection cylinder into a bore in the mold, the nozzle including a central bore in fluid communication with the injection cylinder, the nozzle configured to selectively permit flow of resin into the mold and to exert pressure on resin in the mold through reciprocation of the nozzle in the bore.
An injection molding apparatus for injecting resin into a mold, the apparatus comprising:
- an injection cylinder in fluid communication with the mold, wherein movement of a piston within the cylinder injects a selected quantity of resin into the mold;
- a plasticizing unit including a flighted screw rotating in a heated containment barrel for plasticizing resin the plasticizing unit in selective fluid communication with the injection cylinder for supplying the injection cylinder with plasticized resin;
- a conduit connecting the plasticizing unit to the injection cylinder to communicate resin from the plasticizing unit to the injection cylinder;
- a secondary plunger arranged for reciprocation within the piston, wherein the secondary plunger selectively exerts pressure on resin in the injection cylinder independently of the piston;
- and
- a check valve between the conduit and the injection cylinder to prevent pressure developed in the injection cylinder from acting on one of the conduit and plasticizing unit.
An injection molding apparatus for injecting resin into a mold, the apparatus comprising:
- an injection cylinder in fluid communication with the mold, wherein movement of a piston within the cylinder injects a selected quantity of resin into the mold;
- a plasticizing unit including a flighted screw rotating in a heated containment barrel for plasticizing resin the plasticizing unit in selective fluid communication with the injection cylinder for supplying the injection cylinder with plasticized resin;
- a conduit connecting the plasticizing unit to the injection cylinder to communicate resin from the plasticizing unit to the injection cylinder;
- an inlet in the injection cylinder connected to the conduit;
- and
- a channel formed in the piston that is movable between an open position aligned with the inlet and a closed position in which the piston obstructs the inlet.
Dependencies are inferred from the claim text.