Molding apparatus and methods
A plastic molding system comprises: dispensing, pre-shaping and shaping cells and a transport subsystem. The dispensing cell has a station for dispensing a dose of plastic feedstock. The pre-shaping and shaping cells each comprise a plurality of stations for shaping the workpiece into a preform shape and into a final shape, respectively. The transport subsystem advances a workpiece along a selected one of a plurality of process paths to form a molded article. Each of the plurality of process paths is defined by a combination of stations of the dispensing cell, the pre-shaping cell and the shaping cell.
1. An apparatus for transporting molten molding material, comprising:
a vessel having an internal cavity for receiving said molten molding material through an orifice and preventing flow of said material during transport;
a coupling assembly defining an orifice for transfer of molding material with a processing station, said coupling assembly having a locating surface configured to matingly engage a corresponding locating feature of a processing station to thereby align said orifice with said processing station to transfer molding material;
a displacement member received in said cavity and extendable into said cavity to displace said molten molding material out of said vessel; and
a thermal regulating assembly on said vessel for controlling a thermal profile of said molten molding material, wherein said thermal regulating assembly comprises a heat sink.
2. The apparatus of claim 1 , wherein said displacement member comprises a piston received in the cavity.
3. The apparatus of claim 1 , wherein said orifice is for receiving said molding material from a melter, and said coupling assembly comprises a seal assembly for selectively sealing said orifice.
4. The apparatus of claim 1 , wherein said orifice is a filling orifice for mating to a melter to receive said molten molding material, and an ejection orifice for mating to a mold to force said molten molding material from said vessel into said mold.
5. The apparatus of claim 1 , wherein said thermal regulating assembly comprises an insulator.
6. The apparatus of claim 1 , wherein said thermal regulating assembly includes a heating element.
7. The apparatus of claim 1 , wherein said coupling assembly comprises a movable seal assembly for selectively sealing said orifice.
8. The apparatus of claim 7 , wherein said seal assembly includes a valve stem.
9. The apparatus of claim 8 , wherein said valve stem extends along an axis of said vessel, within said internal cavity.
10. The apparatus of claim 7 , wherein said seal assembly comprises a sliding gate.
11. The apparatus of claim 1 , wherein said vessel comprises a handling feature for releasably securing said vessel to a transport device, for movement of said vessel relative to said processing station.
12. The apparatus of claim 11 , wherein said transport device comprises a guide and said handling feature comprises an adapter configured to engage said vessel and said guide.
13. The apparatus of claim 12 , wherein said coupling assembly is part of said adapter.
14. The apparatus of claim 1 , wherein the vessel comprises a barrel and a tip, the tip fits over and seals with an end portion of the barrel and the barrel and the tip cooperate to define the inner cavity.
15. The apparatus of claim 14 , wherein the barrel and tip may be formed of different materials.
16. The apparatus of claim 14 , wherein the thermal regulating assembly is positioned over at least a portion of the barrel and the tip.
17. The apparatus of claim 14 , wherein the thermal regulating assembly includes a metallic sleeve and a heating coil.
18. The apparatus of claim 14 , wherein the thermal regulating assembly includes a sleeve, wherein the sleeve is a thermal insulator and inhibits heat loss through underlying surfaces of the barrel and the tip.
19. The apparatus of claim 14 , wherein the thermal regulating assembly includes a sleeve, the sleeve is a heat sink, such that it tends to promote heat transfer out of molding material within cavity.
20. An apparatus for transferring a flowable molding material between a container having an internal cavity for holding flowable molding material and a processing station, comprising:
a holder for supporting said container, said holder comprising a nest configured to matingly receive said container;
a coupling device for selectively engaging said container with the processing station, by mating locating surfaces of said container and said processing station, to thereby establish a flow path for said flowable molding material between said container and said processing station; and
a flow actuator for causing flow of said flowable molding material through said flow path;
wherein said nest comprises an interlocking feature for maintaining a position of said container.
21. The apparatus of claim 20 , wherein said apparatus comprises a locking actuator for biasing said container against said interlocking feature.
22. The apparatus of claim 20 , wherein said apparatus comprises a seal actuator for operating a seal of said container.
23. The apparatus of claim 22 , wherein said apparatus comprises a locking actuator for biasing said container against said interlocking feature and wherein said seal actuator is in a nested relationship with one or more of said flow actuator and said locking actuator.
24. The apparatus of claim 20 , wherein said holder comprises a triggering structure for releasing a seal of said container.
25. The apparatus of claim 24 , wherein said triggering structure comprises a guide and said releasing a seal comprises receiving a locking projection in said guide and moving said locking projection as it traverses said guide.
26. The apparatus of claim 20 , wherein said processing station comprises a dispensing station for transferring said flowable molding material to said container.
27. The apparatus of claim 20 , wherein said processing station comprises an injection molding station and said flow actuator is operable to force said flowable molding material from said container to a mold of said injection molding station by displacement of a piston.