US 11,292,178 B2 · Nozzle shut off for injection molding system

Abstract

An injection molding apparatus and method of fabricating a molded part are provided. The apparatus may include a barrel, a nozzle enclosing an end of the barrel and defining an opening in fluid communication with an inside of the barrel, and an extrusion screw positioned at least partially inside the barrel and rotatable relative to the barrel. The extrusion screw may include a screw tip. Relative axial movement between the barrel and the extrusion screw may open or close the opening of the nozzle to permit or prevent, respectively, material flow through the opening of the nozzle. The method may include clamping a mold, opening a nozzle, rotating the extrusion screw to pump a molten material into the mold until the mold is filled, closing the nozzle, and unclamping the mold to release a molded part.

Claims20

Dependent claims

A method of molding a part, comprising:

rotating a screw within a barrel to extrude a molten material through a nozzle opening of a nozzle into a mold cavity;
and
after extruding the molten material through the nozzle opening, inserting a free end of the screw that is defined by a cylindrical tip portion and corresponding in geometry to the nozzle opening into the nozzle opening along an entire axial length of the nozzle opening to displace all of the molten material from the nozzle opening, wherein the cylindrical tip portion rotates with the screw, and wherein the cylindrical tip portion comprises a consistent circular cross-section extending along a longitudinal axis of the screw.

Dependencies are inferred from the claim text.

Facts

Application

15/726,674Filed 6 Oct 2017 · continuation

Priority

4 Dec 2014

Published

US 2018/0029262 A11 Feb 2018

Granted

5 Apr 2022

Term ends

Not estimatedThe source records don’t support an estimate.

Classification37 codes

B29C 48/92
Component parts, details or accessories; Auxiliary operations: measuring, controlling or regulating
B29C 31/04
Handling, e.g. feeding of the material to be shaped , storage of plastics material before moulding; Automation, i.e. automated handling lines in…:…
B29C 45/03
Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor: injection…
B29C 45/13
Injection moulding apparatus: using two or more injection units co-operating with a single mould

Family

Application14/960,115Parent of this continuation · filed 4 Dec 2014

Application62/087,414Us provisional application · filed 4 Dec 2014

Application62/087,449Us provisional application · filed 4 Dec 2014

Application62/087,480Us provisional application · filed 4 Dec 2014

US 2018/0029262 A1Pre-grant publication · published 1 Feb 2018

US 9,808,971 B2Parent of this continuation

US 2016/0158981 A1Published application

US 11,292,178 B2This patent

From the US filing history. Foreign family members aren’t listed.

Nozzle shut off for injection molding system

Life of this patent

Nozzle shut off for injection molding system

Life of this patent

Abstract

Claims20