MOLDING APPARATUS AND METHODS

RELATED APPLICATIONS

This application claims priority from U.S. Provisional patent application 62/724,790, filed August 30, 2018, U.S. Provisional Patent Application 62/770,785, filed November 22, 2018, U.S. Provisional patent application no 62/856,833, filed June 4, 2019, and U.S. Provisional patent application no. 62/866,059, filed June 25, 2019, the disclosures of which are incorporated herein by reference.

TECHNICAL FIELD

This relates to molding, and more particularly, to molding systems defining multiple selectable process paths through process cells.

BACKGROUND

Many plastic molding systems are optimised for production of products in very large quantities. Such systems typically involve complex, multi-cavity molds for production of multiple identical parts simultaneously in each molding cycle.

Successful operation of such processes typically requires extensive custom tooling. For example, multi-cavity molds are custom designed and fabricated for each unique type of part to be produced. Complex melt control mechanisms are required to melt and thermally control molding material, and deliver molten material to each cavity. Molding material is therefore flowed through a fixed conduit to a mold.

While these systems are capable of producing large volumes of products at relatively low per-unit costs, they tend to be less cost-effective for smaller-quantity runs of products, and provide very little flexibility, as product changes generally cannot be made without significant revision or replacement of tooling.

SUMMARY

An example method for use in molding articles comprises: moving a vessel for holding molten molding material along a track to a molten molding material dispensing cell; dispensing a flowable molten molding material to the vessel at the molten molding material dispensing cell; following the dispensing, moving the vessel along the track to a molding cell; at the molding cell, injecting the molten molding material from the vessel to a molder of the molding cell.

In some embodiments, the molding cell has a plurality of molders and the method further comprises, prior to the injecting the molten molding material from the vessel to the molder, selecting the molder from amongst the plurality of molders dependent upon a characteristic of the molten molding material dispensed to the vessel at the molten molding material dispensing cell.

In some embodiments, the characteristic is a volume of the molten molding material dispensed to the vessel.

In some embodiments, the vessel is one of a plurality of vessels and the method further comprises: tracking a position of each vessel.

In some embodiments, the molten molding material dispensing cell has a plurality of dispensers, and the molding cell has a plurality of molders further comprises: moving the each vessel to a selected dispenser of the molten molding material dispensing cell to receive molten molding material, and moving the each vessel to a selected molder of the molding cell dependent upon a characteristic of molten molding material dispensed to the each vessel.

In some embodiments, the characteristic is a composition of the molding material.

In some embodiments, the composition comprises a colorant.

In some embodiments, the composition is a thermoplastic or a thermoset plastic resin.

In some embodiments, the method further comprises, following the injecting the molten molding material to the molder, returning the vessel along a return line of the track back toward the molten molding material dispensing cell.

In some embodiments, the method further comprises, following injecting the molten molding material from each the vessel, returning each the vessel along a return line of the track back toward the molten molding material dispensing cell.

In some embodiments, the selected dispenser is selected based on the characteristic of molten molding material dispensed to the each vessel when the each vessel was previously at the molten molding material dispensing cell.

In some embodiments, the method further comprises transferring articles molded at the molding cell to the return line of the track.

In some embodiments, the method further comprises transferring articles on the return line of the track to selected blow molders of a blow molding cell dependent upon the characteristic of molten molding material.

In some embodiments, the track comprises two carriages and the method further comprises: bringing the two carriages together to trap the vessel between the carriages; and subsequently maintaining the two carriages together while moving the two carriages along the track in order to convey the vessel along the track.

In some embodiments, the method further comprises gripping the vessel with grippers, thereafter separating the two carriages to release the vessel from the track, and thereafter manipulating the vessel with the grippers.

In some embodiments, the method further comprises, upstream of the molten molding material dispensing cell, swapping the vessel for another vessel.

In some embodiments, the vessel has a piston and wherein the injecting comprises moving the piston.

An example system for use in molding articles comprises: a track; a plurality of vessels carried on the track; at least one molten molding material dispenser along the track; at least one molder along the track; and a controller operatively associated with the track for selectively moving each vessel along the track (i) to a given dispenser of the at least one molten molding material dispenser whereat flowable molten molding material is dispensed to the each vessel and (ii) to a given molder of the at least one molder whereat molten molding material is dispensed from the each vessel.

In some embodiments, the system comprises a position sensor interconnected with the controller for tracking a position of the each vessel.

In some embodiments, the at least one dispenser comprises a plurality of dispensers and the at least one molder comprises a plurality of molders, and wherein the controller is configured to select the given molder from the plurality of molders dependent upon a characteristic of molding material dispensed to the each vessel at the given dispenser.

In some embodiments, the track has an outgoing line for carrying the vessels to the at least one molten molding material dispenser and to the at least one molder, and a return line for returning the vessels back toward the at least one molten molding material dispenser.

In some embodiments, the system further comprises a transfer device for transferring articles molded at the given molder to the return line.

In some embodiments, the transfer device is a first transfer device and the system further comprises at least one blow molder along the return line and a second transfer device to transfer the articles on the return line to a given blow molder of the at least one blow molder.

In some embodiments, the return line is parallel to the outgoing line.

In some embodiments, the track comprises a plurality of pairs of carriages, two carriages of each pair of carriages having complementary features for trapping the each vessel between the two carriages when the two carriages are brought together, the controller further operable to selectively bring the two carriages together and to move the two carriages while together in order to move the each vessel on the track.

In some embodiments, the track comprises a plurality of pairs of carriages, two carriages of each pair of carriages having complementary features for trapping at least one of the each vessel or an article of the articles between the two carriages when the two carriages are brought together, the controller further operable to selectively bring the two carriages together and to move the two carriages while together in order to move the each vessel or the article along the track.

In some embodiments, the system further comprises a pair of spring loaded grippers mounted for reciprocal movement transversely of the track such that the grippers may be extended toward the track to deflect around and grip a given the each vessel trapped by the two carriages.

In some embodiments, the each vessel has an identifier and the system further comprises a reader for reading the identifier of the each vessel, and wherein the controller is operatively associated with an output of the reader.

In some embodiments, the system further comprises a shunt line mounted for movement between a first position coupled to an end of the outgoing line and a second position coupled to an end of the return line in order to shunt the vessels from the outgoing line to the return line.

In some embodiments, the return line is parallel to the outgoing line and one of the outgoing line and the return line is directly above another of the outgoing line and the return line.

In some embodiments, the system further comprises at least one vessel re-ordering device upstream of the at least one molten molding material dispenser, the at least one re-ordering device comprising a reciprocal turntable with a plurality of vessel grippers.

In some embodiments, the characteristic is a composition of the molding material.

In some embodiments, the composition is a thermoplastic or a thermoset plastic resin.

An example plastic molding system comprises: a feedstock cell comprising a feedstock station for depositing plastic feedstock into a vessel, deposited plastic feedstock defining a workpiece; a pre-shaping cell comprising a plurality of pre-shaping stations each for shaping a given workpiece into a preform shape by injection into a pre-shaping mold; a shaping cell comprising a plurality of shaping stations each for shaping one workpiece from the preform shape to a final shape in a mold; a transport subsystem for advancing each workpiece along a selected one of a plurality of process paths to form a molded article from the each workpiece, wherein multiple ones of the process paths are defined by a combination of the feedstock station, a pre-shaping station of the pre-shaping cell and a shaping station of the shaping cell.

In some embodiments, the feedstock cell is a dispensing cell and wherein the feedstock station is a dispensing station for dispensing a dose of plastic feedstock defining each the workpiece.

In some embodiments, the dispensing cell comprises a plurality of dispensing stations, and wherein each of the plurality of process paths includes one the dispensing station.

In some embodiments, the system further comprises a thermal conditioning cell for producing a desired thermal profile in each the workpiece between the primary and secondary shaping cells.

In some embodiments, the plurality of process paths comprise a first process path for producing first molded articles having a first characteristic and a second process path for producing second molded articles having a second characteristic different from the first characteristic.

In some embodiments, the characteristic comprises a shape.

In some embodiments, each the pre-shaping station comprises an injection molding apparatus and each the shaping station comprises a blow molding apparatus.

In some embodiments, each the dispensing station comprises an extruder for dispensing the plastic feedstock as molten plastic.

In some embodiments, the system comprises a post-shaping cell for performing a finishing operation on the workpiece in the final shape.

In some embodiments, the workpiece in the final shape is a bottle and the post-shaping cell comprises a filling station.

In some embodiments, the post-shaping cell comprises a labelling station.

In some embodiments, the post-shaping cell comprises a capping station.

An example plastic molding system for a process comprising dispensing and shaping operations, comprises: a dispensing cell comprising a dispensing mechanism for dispensing doses of a plastic feedstock into vessels to create workpieces; a shaping cell comprising a

plurality of shaping stations, each shaping station having a mold for receiving the plastic feedstock from a vessel and for forming the workpiece into a desired shape; and a transport subsystem for advancing each the workpiece along a selected one of a plurality of possible process paths through each of the dispensing cell and the shaping cell, to form a molded article from the each workpiece, wherein multiple ones of the possible process paths are defined by a combination of the dispensing mechanism and different ones of the plurality of shaping stations.

In some embodiments, the system comprises a conditioning cell comprising a plurality of conditioning stations, each for applying a treatment to one workpiece prior to processing of the one the workpiece in the shaping cell, and wherein each of the possible process paths includes one of the conditioning stations.

In some embodiments, the conditioning cell is configured under computer control to apply the treatment.

In some embodiments, the dispensing cell comprises a plurality of dispensing mechanisms, and wherein each of the possible process paths includes one the dispensing mechanism.

In some embodiments, the dispensing cell is for dispensing individual doses of the plastic feedstock, each to form a single molded article.

In some embodiments, each of the possible process paths includes a different combination of one the dispensing mechanism, and one the shaping station.

In some embodiments, the plurality of possible process paths comprise a first process path for producing first molded articles having a first characteristic and a second process path for producing molded articles having a second characteristic different from the first characteristic.

In some embodiments, the characteristic comprises a shape.

In some embodiments, the shaping cell is a primary shaping cell and each shaping station is a primary shaping station for performing a primary shaping operation to form a pre- shaped article, and the system further comprises a secondary shaping cell for performing a secondary shaping operation to form each the molded article by re-shaping each the pre-shaped article.

In some embodiments, each the primary shaping station comprises an injection molding apparatus and wherein the secondary shaping cell comprises a plurality of secondary shaping stations each comprising a blow molding apparatus.

In some embodiments, the dispensing cell comprises an extruder for dispensing the plastic feedstock as molten plastic.

In some embodiments, the transport subsystem comprises a guide mechanism and the plurality of process paths are at least partially defined by the guide mechanism.

In some embodiments, the guide mechanism comprises a loop and a plurality of branches each connecting stations of the cells with the loop.

In some embodiments, the guide mechanism comprises a track and a carriage mounted for movement on the track.

In some embodiments, the guide mechanism comprises a plurality of carriages, and the transport subsystem comprises a plurality of diverting devices for selectively initiating directional change of the carriages to individual stations of the cells.

In some embodiments, the primary shaping cell is for performing a primary shaping operation to form a pre-shaped article, and the transport subsystem comprises a plurality of pre-shape carriages mounted for movement along the track, for receiving pre-shaped articles from the primary shaping cell and carrying the pre-shaped articles to a subsequent processing station.

In some embodiments, the system comprises a post-shaping cell for performing a finishing operation on the workpiece in the final shape.

In some embodiments, the workpiece in the final shape is a bottle and the post-shaping cell comprises a filling station.

In some embodiments, the post-shaping cell comprises a labelling station.

In some embodiments, the post-shaping cell comprises a capping station.

An example method of molding plastic articles in a molding system comprising a plurality of feedstock providing stations and a plurality of shaping stations, comprises: forming a first molded article by conveying a first quantity of feedstock through the molding system in a first process path, wherein the conveying comprises moving the first quantity in a vessel; and forming a second molded article by conveying a second quantity of feedstock through the molding system in a second process path different from the first process path and partially overlapping with the first process path, wherein the conveying comprises moving the second quantity in a further vessel; wherein each of the first process path and the second process path includes a feedstock providing station of the plurality of feedstock providing stations and a shaping station of the plurality of shaping stations.

In some embodiments, the molding system comprises at least one conditioning station and each of the first process path and the second process path includes one the dose dispensing station, one the shaping station, and one the conditioning station.

In some embodiments, the shaping stations are primary shaping stations and each of the first process path and the second process path includes one the dispensing station, a primary shaping station, one the conditioning station and a secondary shaping station.

In some embodiments, the first process path includes a first shaping station and the second process path includes a second shaping station different from the first shaping station.

In some embodiments, the conveying the first dose of feedstock comprises dispensing the first dose of feedstock into a first vessel and the conveying the second dose of feedstock comprises dispensing the second dose of feedstock into a second vessel.

In some embodiments, the conveying the first dose of feedstock comprises dispensing the first dose from a first dispensing station and the conveying the second dose of feedstock comprises dispensing the second dose from a second dispensing station different from the first dispensing station.

In some embodiments, the first molded article and the second molded article have different shapes.

In some embodiments, the first molded article and the second molded article have different sizes.

In some embodiments, the first molded article and the second molded article are formed of different materials.

In some embodiments, each one of the first process path and the second process path includes an injection molding apparatus and a blow molding apparatus.

In some embodiments, the conveying the first dose of feedstock and conveying the second dose of feedstock comprises conveying carriages along a track.

In some embodiments, the conveying the first dose of feedstock and conveying the second dose of feedstock comprises operating a diverting device to initiate a change in direction from a track loop towards individual ones of the shaping stations.

In some embodiments, the molding system comprises a post-shaping station and the method further comprises performing a finishing operation in the post-shaping station.

In some embodiments, the finishing operation comprises filling.

In some embodiments, the finishing operation comprises labeling.

In some embodiments, the finishing operation comprises capping.

An example method for use in molding articles comprises: dispensing a dose of molten plastic material into a vessel; moving the vessel with the dose therein to a selected forming station of a plurality of available forming stations; transferring the dose of molten material from the vessel to a forming apparatus at the selected forming station; forming a molded article from the dose in the forming apparatus.

In some embodiments, the molded article is a pre-shaped molded article and the method further comprises moving the pre-shaped molded article to a finishing station of a plurality of available finishing stations and forming a finished molded article from the pre-shaped molded article at the finishing station.

An example system for molding articles comprises: means for dispensing a dose of molten plastic material into a vessel; means for moving the vessel with the dose therein to a selected forming station of a plurality of available forming stations; means for transferring the dose of molten material from the vessel to a forming apparatus at the selected forming station; means for forming a molded article from the dose in the forming apparatus.

In some embodiments, the means for dispensing comprises a plurality of dispensers, each for dispensing a molten plastic material having a different composition.

An example apparatus for transporting molten molding material comprises: a vessel having an internal cavity for receiving the molten molding material through an orifice and preventing flow of the material during transport; a coupling assembly for selectively mating to a processing station to transfer molding material; an ejection mechanism operable to force the molten molding material out of the vessel.

In some embodiments, the ejection mechanism comprises a piston received in the cavity.

In some embodiments, the vessel comprises an orifice for receiving the molding material from a melter, and the coupling assembly comprises a seal assembly for selectively sealing the orifice.

In some embodiments, the orifice is a filling orifice for mating to a melter to receive the molten molding material, and an ejection orifice for mating to a mold to force the molten molding material from the vessel into the mold.

In some embodiments, the apparatus comprises a thermal regulating assembly on the container for controlling a thermal profile of the molten molding material.

In some embodiments, the thermal regulating assembly comprises an insulator.

In some embodiments, the thermal regulating assembly comprises a heat sink.

In some embodiments, the thermal regulating assembly comprises a sleeve around the vessel.

In some embodiments, the thermal regulating assembly includes a heating element.

In some embodiments, the coupling assembly is a seal assembly for selectively sealing the orifice.

In some embodiments, the seal assembly includes a valve stem.

In some embodiments, the valve stem extends along an axis of the vessel, within the internal cavity.

In some embodiments, the seal assembly comprises a sliding gate.

In some embodiments, the vessel is configured to releasably engage with a transport device, for movement of the vessel relative to a processing station.

In some embodiments, the vessel comprises a handling feature for releasably securing the vessel to a transport device.

In some embodiments, the transport device comprises a guide and the handling feature comprises an adapter configured to engage the vessel and the guide.

In some embodiments, the seal assembly is part of the adapter.

An example method of transporting molten molding material comprises: receiving molten molding material in an internal cavity of a vessel through an orifice; moving the vessel along a transport path; preventing flow of the material during the moving; mating the vessel with a mold; transferring the molten molding material to the mold by forcing the molten molding material out of the vessel.

In some embodiments, forcing the molten molding material out of the vessel comprises moving a piston in the internal cavity.

In some embodiments, the preventing flow comprises sealing the orifice.

In some embodiments, the transferring comprises forcing material out of the vessel through the orifice.

In some embodiments, the method comprises regulating heat transfer with the vessel.

In some embodiments, the regulating heat transfer comprises insulating the vessel to regulate heat loss.

In some embodiments, the regulating heat transfer comprises removing heat from the vessel with a heat sink.

In some embodiments, the regulating heat transfer comprises introducing heat to the vessel with a heating element after the receiving.

In some embodiments, the method comprises releasably engaging the vessel with a transport device for the moving.

In some embodiments, the transport device comprises a guide and the releasably engaging comprises attaching the vessel to the guide with an adapter.

In some embodiments, the method comprises sealing the orifice with the adapter.

An example apparatus for transferring a flowable molding material between a container and a processing station comprises: a holder for supporting a container having an internal cavity for holding flowable molding material, the holder comprising a nest configured to matingly receive the container; a coupling device for selectively engaging the container with the processing station, to thereby establish a flow path for the flowable molding material between the container and the processing station; a flow actuator for causing flow of the flowable molding material through the flow path.

In some embodiments, the nest comprises an interlocking feature for maintaining a position of the container.

In some embodiments, the apparatus comprises a locking actuator for biasing the container against the interlocking feature.

In some embodiments, the apparatus comprises a seal actuator for operating a seal of the container.

In some embodiments, the seal actuator is in a nested relationship with one or more of the flow actuator and the locking actuator.

In some embodiments, the holder comprises a triggering structure for releasing a seal of the container.

In some embodiments, the triggering structure comprises a guide and the releasing a seal comprises receiving a locking projection in the guide and moving the locking projection as it traverses the guide.

In some embodiments, the processing station comprises a dispensing station for transferring the flowable molding material to the container.

In some embodiments, the processing station comprises an injection molding station and the flow actuator is operable to force the flowable molding material from the container to the mold by displacement of a piston.

BRIEF DESCRIPTION OF DRAWINGS

In the drawings, which depict example embodiments:

FIG. 1 is a schematic diagram of a molding system;

FIG. 2 is a schematic diagram of a molding system with process cells defining multiple paths through the system;

FIG. 3 is an isometric view of a molding system;

FIG. 4A-4B are isometric views of a dispensing station of the system of FIG. 3;

FIGS. 4C-4E are isometric views of sub-assemblies of the dispensing station of FIG. 4A;

FIGS. 4F-4G are enlarged partial isometric views of a barrel unit;

FIG. 4F1 is a schematic view of a coupling for holding the barrel unit of FIGS. 4F-4G to a drive unit;

FIGS. 4I-4J are enlarged partial isometric views of the barrel unit of FIG. 4F with a drive unit;

FIG. 4K is a schematic diagram of a removal tool for removing a barrel unit from a drive unit;

FIGS. 4L-40 are enlarged partial cutaway views showing a process of coupling a barrel unit to a drive unit;

FIGS. 4P-4R are enlarged partial cutaway views showing a process of removing a barrel unit from a drive unit;

FIG. 4S is a schematic view of the removal tool of FIG. 4K installing a barrel unit to a drive unit;

FIG. 5 is a longitudinal cross-sectional diagram of the dispensing station of FIG. 4;

FIGS. 6A-6B are isometric and isometric cutaway views, respectively, of a vessel for transporting molding material;

FIGS. 7A-7B are isometric views of the material vessel of FIGS. 6A-6B and a carrier;

FIGS. 8A, 8B, 8C, and 8D are side and cross sectional views showing stages of a dispensing operation at the dispensing station of FIG. 4;

FIG. 9 is an exploded view of a gate assembly;

FIGS. 10A-10B are enlarged cross-sectional views showing operation of the gate assembly of FIG. 9;

FIG. 11 is an isometric view of a shaping station of the system of FIG. 3;

FIGS. 12A-12D are cross-sectional and isometric views of the shaping station of FIG. 11;

FIGS. 13A-13B are isometric and side views, respectively, of a linkage for a clamping assembly;

FIG. 13C is a diagram of forces on the linkage of FIGS. 13A-13B;

FIGS. 14A-14B are isometric and side views, respectively, of another linkage for a clamping assembly;

FIGS. 15A-15B are isometric and side views, respectively, of another linkage for a clamping assembly;

FIG. 16 is a side view of another linkage for a clamping assembly;

FIG. 17 is an isometric view of a core actuation assembly of the shaping station of FIG. 11 ;

FIGS. 18A-18B are isometric and cross-sectional views, respectively, of a core positioning actuator of the core actuation assembly of FIG. 17;

FIG. 19 is an isometric view of a loading actuator of the core actuation assembly of FIG. 17;

FIG. 20 is a partial cutaway view of the loading actuator of FIG. 19;

FIG. 21A is a schematic view showing interlocking between the core positioning actuator of FIGS. 18A-18B and the loading actuator of FIG. 17;

FIG. 21B is a partial cross-sectional view of the core positioning actuator of FIGS. 18A-18B and the loading actuator of FIG. 17, showing interlocking;

FIG. 22 is an isometric view of a secondary mold opening actuator of the core actuation assembly of FIG. 17;

FIGS. 23A-23D are side, isometric, enlarged top and enlarged perspective views, respectively, of a shaper module of the shaping station of FIG. 11 ;

FIG. 24A-24B are front isometric and top elevation views of another shaping station;

FIG. 24C is a rear isometric view of the shaping station of FIG. 24A;

FIG. 24D is front isometric view of support structures of the shaping station of FIG. 24A;

FIGS. 24E-24F are isometric views of the support structures of FIG. 24D, cutaway at lines E-E and F-F in FIG. 24B;

FIG. 24G is an isometric view of the shaping station of FIG. 24A, cutaway to show internal components;

FIG. 24F1 is an enlarged partial cross-sectional of the shaping station of FIG. 24A;

FIGS. 24I-24J are isometric and cross-sectional views of the shaping station of FIG. 24A in a mold-open state;

FIGS. 24K-24L are isometric and cross-sectional views of the shaping station of FIG. 24A in a mold-open state, with the mold core in a molding position;

FIGS. 24M-24N are isometric and cross-sectional views of the shaping station of FIG. 24A in a mold-closed state;

FIGS. 240-24P are isometric and cross-sectional views of the shaping station of FIG. 24A in a mold-closed state, with a preload force applied to the mold core;

FIGS. 24Q-24R are isometric and cross-sectional views of the shaping station of FIG. 24A in a mold-open state;

FIGS. 24S-24T are isometric and cross-sectional views of the shaping station of FIG. 24A during mold removal;

FIG. 25A is a side perspective view of a one embodiment of part of a mold assembly;

FIG. 25B is a front elevation view of a portion of the part of the mold assembly of FIG. 25 A;

FIG. 25C are side perspective views of the embodiment of portions of the part of the mold assembly of FIG. 25 A;

FIGS. 25D, E and F are similar side perspective views as FIG. 25C, of portions of the part of the mold assembly of FIG. 25 A;

FIG. 25G is top perspective view of an embodiment of a mold cavity block;

FIG. 25F1 is a is top perspective view of an embodiment of a cavity plate that includes the mold cavity block of FIG. 25G;

FIG. 251 is top perspective view of an alternate embodiment of a mold cavity block;

FIG. 25J is top plan view of the mold cavity block of FIG. 251

FIG. 25K is another top perspective view of the mold cavity block of FIG. 251;

FIG. 26A and 26B are side perspective views of an alternate embodiment of portions of a mold assembly;

FIG. 26C is a top plan section view at part marked 26C in FIG. 26A;

FIG. 26D is a side perspective view of part of the embodiment of the portions of the mold assembly of FIGS. 26A and 26B;

FIG. 26E is a perspective view of a disconnected components of the part shown in FIG. 26D;

FIG. 26F is a perspective view of another disconnected components of the part shown in FIG. 26D;

FIG. 26G are rear elevation views of the disconnected component of the part shown in FIG. 26D;

FIG. 26F1 is top plan view of the mold cavity block used in the part of FIG. 26D;

FIG. 261 is a top perspective view of the mold cavity block of the part of FIG. 26D;

FIG. 26J is a top perspective view of an alternate mold cavity block that can be employed in the part of FIG. 26D;

FIG. 27A is a top perspective view of a base block;

FIG. 27B is a rear perspective view of the base block of FIG. 27A;

FIG. 28A is an assembly diagram for part of a mold assembly; and

FIG. 28B is a schematic view of a cooling fluid circuit.

FIG. 29 is a cross-sectional view of a mold of the shaping station of FIG. 11 and a vessel;

FIG. 30 is a sequence of overhead and isometric views showing sealing of a vessel;

FIG. 31 is an isometric view showing sealing of another vessel;

FIG. 32 is an isometric view of the actuator assembly of the shaping station of FIG. 11 ;

FIGS. 33A, 33B and 33C are isometric, cutaway and cross-sectional views, respectively, of a vessel and an actuation assembly at the shaping station of FIG. 11 ;

FIGS. 34A-34K are cross-sectional and partial cross-sectional views showing stages of a shaping operation at the shaping station of FIG. 11 ;

FIGS. 35A-35F are cutaway views of the vessel and actuation assembly of FIGS. 17A-17C, showing operations of the vessel and actuation assembly;

FIG. 36 is an exploded view of a gate assembly;

FIGS. 37A-37B are enlarged cross-sectional views showing operation of the gate assembly of FIG. 36;

FIG. 38 is an isometric view of a conditioning station and a shaping station of the system of FIG. 3.

FIG. 39 is a side cross-sectional view of the conditioning station of FIG. 38;

FIGS. 40A, 40B and 40C are side and cross-sectional views showing stages of a conditioning operation at the conditioning station of FIG. 38;

FIG. 41A is an isometric view of a shaping station;

FIG. 41B is a side view of a press of the shaping station of FIG. 41;

FIG. 42 is a side view of another shaping station;

FIG. 43 is a top view of the shaping station of FIG. 42;

FIG. 44 is an exploded view of a mold and services plates of the shaping station of FIG. 42;

FIG. 45 is an exploded view of the mold of FIG. 44;

FIG. 46 is a cross-sectional view of the mold of FIG. 44;

FIGS. 47A-47B are top and side schematic views of the shaping station of FIG. 42 during mold removal;

FIGS. 48A-48B are top and side schematic views of the shaping station of FIG. 42 during mold removal;

FIGS. 49A-49B are top and side schematic views of the shaping station of FIG. 42 during mold removal;

FIG. 50 is a schematic view showing mold components at a shaping station;

FIGS. 51A, 51B, 51C and 51D are schematic views showing stages of a shaping operation with the mold components of FIG. 50;

FIG. 52 is a top plan view of the molding system of FIG. 3, showing a transport subsystem;

FIG. 53 is a plan view of an injection molding system in accordance with another embodiment;

FIG. 54 is a cross-sectional view along the lines I-I of FIG. 53;

FIG. 55A is a side view of a track section;

FIG. 55B is a cross-sectional view along the lines II-II of FIG. 55A;

FIG. 55C is a perspective fragmentary view of a portion of the track of the system of FIG. 55A;

FIG. 56 is a side view of a portion of the system of FIG. 53;

FIG. 57 is a perspective fragmentary view of another portion of the system of FIG. 53;

FIG. 58 is a perspective fragmentary view of a further portion of the system of FIG. 53;

FIG. 59 is a perspective fragmentary view of a yet a further portion of the system of FIG. 53;

FIG. 60 is a perspective detail view of a portion of FIG. 58;

FIG. 61 is a top view of a conditioner and shaper station and associated transfer system;

FIG. 62 is a side view of the stations and transfer system of FIG. 61

FIGS. 63A-63B are isometric and side views, respectively, of a carriage of the transfer system of FIG. 61;

FIG. 64 is a block diagram;

FIG. 65 is a perspective fragmentary view of a portion of a modified system;

FIG. 66 is a perspective detail view of a portion of FIG. 63.

FIG. 67 is a flow chart showing a method of transporting molding material; and

FIG. 68 is a flow chart showing a method of producing plastic molded products.

DETAILED DESCRIPTION

FIG. 1 schematically depicts an example plastic molding system 100 for producing plastic molded articles. As described in further detail below, plastic molding system 100 is capable of carrying out molding processes comprising dispensing, conditioning and shaping operations.

Plastic molding system 100 includes a plurality of process cells, each including one or more process stations at which an operation of a molding process can be performed. Specifically, the depicted embodiment comprises a dispensing cell 102, shaping cells 104, 106 and a conditioning cell 108. Other embodiments may include more or fewer cells and carry out molding processes with more or fewer process steps. Alternatively or additionally, plastic molding system 100 may include cells for other operations. For example, plastic molding system 100 may include cells for post-molding operations such as container filling, labelling or capping.

The process cells of plastic molding system 100 are connected by a transport subsystem 110.

Any of process cells 102, 104, 106, 108 may have more than one station of a given type. Transport subsystem 110 selectively connects stations of the process cells to one another. Transport subsystem 110 is configurable to define multiple possible process paths through process cells of molding system 100. For example, transport subsystem 110 may be capable of transporting an article from a given station in one process cell 102, 104, 106, 108, to a selected one of a plurality of possible stations in a another process cell 102, 104, 106, 108.

FIG. 2 schematically depicts an example embodiment with a dispensing cell 102 having 4 dispensing stations 102-1, 102-2, 102-3, 102-4; a shaping cell 104 having 8 shaping stations 104-1, 104-2, 104-3, 104-4, 104-5, 104-6, 104-7, 104-8; a shaping cell 106 having 2 shaping stations 106-1, 106-2; and a conditioning cell 108 having 2 conditioning stations 108-1, 108-2.

In the embodiment of FIG. 2, transport subsystem 110 is capable of connecting any of dispensing stations 102-1, 102-2, 102-3, 102-4 to any of shaping stations 104-1, 104-2, ...104-8; and of connecting any of shaping stations 104-1, 104-2,... 104-8 to any of conditioning stations 108-1, 108-2; and of connecting any of conditioning stations 108-1, 108-2 to any of shaping stations 106-1, 106-2. Thus, numerous possible paths are defined through molding system 100. As depicted, there exist 128 unique combinations of one dispensing station 102, one shaping station 104, one conditioning station 108 and one shaping station 106 and each unique combination corresponds to a possible path. In some embodiments, one or more of the process cells may be omitted from some paths, such that additional paths are possible. For example, conditioning at conditioning cell 108 or shaping at shaping cell 106 may not be required in all instances.

In other embodiments, more or fewer stations may be present in each process cell, and more or fewer paths through the molding system may be possible.

In some embodiments, process cells or stations of process cells may be physically separated from one another. Transport subsystem 110 may include apparatus for moving molding material through space between process cells or stations thereof. The apparatus may include one or both of vessels 124 (FIGS. 6A-6B) for holding molding material and carriers 125 (FIG. 7) for moving the vessels through space, e.g. along a guide or track, between the process cells or stations. In the embodiment described in detail herein, the vessel is selectively coupled to the carrier such that the vessel may be coupled and decoupled to the carrier at one or more process stations. In another embodiment, not shown, the vessel could otherwise be fixed to the carrier and the process stations configured to accommodate the vessel that remains connected with the carrier. In either case, the vessel may be thermally insulated from the carrier.

In the depicted embodiment, shaping cell 104 contains injection molding stations and shaping cell 106 contains blow molding stations. Conditioning cell 108 contains stations for thermally conditioning articles to prepare for blow molding. For example, injection molded articles formed at shaping cell 104 may cool after molding and be subsequently warmed to a temperature suitable for blow molding. Alternatively or additionally, stations of conditioning cell 108 may be configured to create a specific desired thermal profile in an article. For example, some shaping operations may call for an input article having a non-uniform temperature distribution. Stations of conditioning cell 108 may generate such temperature distribution by selectively heating specific regions, with or without a net transfer of heat into or out of the article. In some embodiments, articles may experience a net loss of heat in conditioning cell 108, despite

warming of specific regions. Thus, stations of conditioning cell 108 may achieve thermal profiles not easily achieved by heat input at the dispensing cell 102.

As explained in further detail below, each station may have identical or unique characteristics. For example, the dispensing stations of dispensing cell 102 may each be configured to dispense the same or a different feedstock (e.g. a different material and/or colour). The shaping stations of shaping cells 104, 106 may be configured to mold articles having identical or different shapes, features or the like. The conditioning stations of conditioning cell 108 may each be configured to condition parts in common or to a different state. Accordingly, molding system 100 may be configured so that it is simultaneously capable of producing up to 128 identical or unique parts at any time. Alternatively or additionally, molding system 100 may be configured so that identical parts may be produced on multiple paths. For example, a single dispensing station can produce shots of feedstock to feed multiple stations of shaping cells 104, 106. In some embodiments, cells can be rapidly reconfigured. Accordingly, the number of system resources being used to produce parts of a given type may vary.

Each unique path through molding system 100 includes a unique combination of selected stations of dispensing cell 102, shaping cells 104, 106 and possibly other process cells such as, for example, the conditioning cell 108. Likewise, each unique combination of stations may produce finished articles with identical or unique characteristics. For example, different stations of dispensing cell 102 may produce articles having different colour material type or weight. Different stations of shaping cells 104, 106 may produce articles having different shapes. Different stations of conditioning cell 108 may produce articles having different shapes or other characteristics.

FIG. 3 is a perspective view of molding system 100. In the depicted embodiment, molding system 100 is for forming hollow plastic articles such as bottles or other containers. Molding system 100 has two shaping cells. Specifically, shaping cell 104 is an injection molding cell for molding a dose of feedstock material into a molded preform shape. Shaping cell 106 is a blow molding cell (specifically, a stretch blow-molding cell) for transforming a preform of a particular shape into a finished hollow container of another, (e.g. a further-expanded) shape. Conditioning cell 108 prepare in-progress articles for operations performed at a shaping cell. Transport subsystem 110 links stations of the respective cells 102, 104, 106, 108. Links between cells are flexible. For example, in some embodiments, transport subsystem 110 links every station of each cell to every station of the neighboring cells. In other examples, some or all stations in a given cell are each linked to a plurality of stations in a neighboring cell. In some examples, some

stations may be linked to stations of neighboring cells in a 1:1 manner. For instance, in the embodiment of FIG. 3, each station of dispensing cell 102 is linked to a plurality of stations of shaping cell 104, and each station of shaping cell 104 is linked to a plurality of stations of conditioning cell 108. Flowever, each station of conditioning cell 108 is linked to one corresponding station of shaping cell 106.

Feedstock Dispensing

With primary reference to FIGS. 4A-4S, details of an example dispensing cell 102 will now be described.

Each station 102-1, 102-2, 102-3, 102-4 of dispensing cell 102 comprises one or more devices for melting a feedstock such as a plastic feedstock and for transferring the feedstock. In the depicted embodiment, the dispensing devices output molding material in doses of a specific size. Flowever, in other embodiments, the dispensing devices may simply perform bulk transfer of molding material, without precise metering of dose size.

In the depicted embodiment, each station of dispensing cell 102 comprises an extruder 112. Flowever, other types of dispensing devices are possible. For example, melting and dispensing doses of feedstock may be accomplished by use of a conduction melter. In the depicted example, extruders 112 receive feedstock material in the form of polyethylene terephthalate (PET) pellets. Flowever, other feedstock materials and other forms are possible. For example, feedstock may be provided as a filament (e.g. on a spool), or as bars or blocks.

Extruders 112 may dispense different feedstock materials. In some examples, extruders 112 may dispense feedstock materials in differing volume, colors, different material types or grades, or at different temperatures. In some embodiments, extruders may be capable of dosing or blending additives, such as dyes or oxygen scavenging agents, into the feedstock material. In some embodiments, extruders 112 may be of different sizes, or may be configured to dispense feedstock at different rates or in different dose sizes. For example, system 100 may be set up to form containers of different size, with each extruder 112 being configured to dispense feedstock in doses corresponding to a specific size.

FlGs. 4A-4B are isometric and exploded views, respectively of an extruder 112 showing components thereof in greater detail. As depicted, extruder 112 has a barrel 114, in which a screw 116 (FIG. 5) is housed, and a drive unit 115 for driving rotation of the screw 116. Rotation of the screw 116 is driven by a drivetrain 130 within drive unit 115, which may include an

electric motor. Barrel 114 has an inlet opening for supply of feedstock and an outlet orifice 122 (FIG. 5) for dispensing of molten feedstock into a vessel 124.

Referring to FIG. 4B, in the depicted embodiment, extruders 112 are mounted to supports 162 within dispensing cell 102. A set of supports 162 may be provided for each dispensing station 102-1, 102-2, 102-3, 102-4. As depicted, barrel 114 and the screw 116 within barrel 114

(collectively referred to as barrel unit 117) are releasably coupled to drive unit 115. Specifically, a coupling 161 rotationally couples the screw 116 to drivetrain 130 and one or more locating features 163 are received in corresponding recesses of supports 162 to position and secure barrel 114 relative to the support 162. Alternatively, alignment features 163 may be part of supports 162 and may be received in corresponding recesses on barrel 114. Supports 162 may include actuators for selectively engaging or releasing locating features 163. Thus, barrel 114 and screw 116 may be released and removed as a unit and replaced by another barrel 114 and screw 116. Coupling 161 and locating features 163 are located on one or both of a coupling block 4010 of barrel unit 117 and a frame 4012 of drive unit 115. References herein to removal, replacement or installation of extruders 112 are intended to include removal, replacement or installation of a barrel 114 and screw 116 as an assembly. In this way, extruder characteristics or characteristics of a feedstock may be rapidly and easily changed.

In some embodiments, removal, replacement or installation of extruders 112 may be affected automatically. For example, extruders 112 may be gripped and removed from supports 162 and may be moved by one or more robots under computer control. The computer control may be part of an overall control system of system 100, and releasing or engaging of locating features such as locating features 163 on barrel 114 may be coordinated with operation of the robot, such that extruders 112 are securely retained upon installation by a robot, and until subsequent removal by a robot.

FIGS. 4C and 4D depict barrel unit 117 and drive unit 115 of an extruder 112 in greater detail. In the configuration of FIG. 4C, barrel unit 117 is coupled to drive unit 115. In the configuration of FIG. 4D, barrel unit 117 is released from drive unit 115.

As depicted, barrel unit 117 includes a barrel 4002 and a screw 116 within barrel 4002. A nozzle assembly 4006 is positioned at the distal end of barrel 4002, in which outlet orifice 122 is defined. Rotation of screw 116 within barrel 4002 causes heating and melting of molding material, and conveys the molding material towards outlet orifice 122 in nozzle assembly 4006. A shroud 4008 is positioned around barrel 4002. During operation, barrel 4002 may become

very hot. Shroud 4008 serves as a barrier to guard against damage to surrounding components and to protect against injury to operators.

Barrel 4002 is mounted to coupling block 4010. For example, barrel 4002 may have a flange (not shown) which interfaces with block 4010 and is secured thereto by fasteners. As will be described in greater detail, screw 116 is received in and supported by barrel 4002.

Nozzle assembly 4006 includes a thermal conditioning element 4007 proximate outlet 122. Thermal conditioning element 4007 maintains nozzle assembly 4006 at a desired temperature, to in turn control the temperature of molding material in nozzle assembly 4006 and molding material exiting nozzle assembly 4006 through outlet 122. One or more temperature measurement devices such as thermocouples may be positioned at nozzle assembly 4006, and thermal conditioning element 4007 may be controlled based on measurements from such devices.

Drive unit 115 and barrel unit 117 are connected by way of a coupling system operated by one or more actuators. The one or more actuators are operable to couple and decouple the drive unit 115 and barrel unit 117 using the coupling system. That is, the coupling system is operable to physically fix barrel unit 117 in position relative to drive unit 115. The coupling system is further operable to connect screw 116 with the drive unit 115 for driving rotation of the screw 116. In the depicted embodiment, the coupling system includes a retaining mechanism 4014 and a drive mechanism 4016. Retaining mechanism 4014 is operable to physically hold barrel unit 117 in place against drive unit 115. Drive mechanism 4016 rotationally connects drive unit 115 to screw 116 for rotating the screw.

In the depicted embodiment, retaining mechanism 4014 and drive mechanism 4016 are operated by separate actuators. In other embodiments, a single actuator may operate both of retaining mechanism 4014 and drive mechanism 4016. In other embodiments, a single mechanism may provide both the retention and drive functions.

In the depicted embodiment, the actuators for retaining mechanism and drive mechanism 4016 are pneumatic. Flowever, other types of actuators may be used, including electro-mechanical actuators such as solenoids, magnetic actuators, or hydraulic actuators.

Barrel unit 117 further includes one or more service ports 4018, each for connecting to a corresponding port of drive unit 115 or proximate drive unit 115. Service ports may include, for example, conduits for circulation of coolant such as water to and from barrel unit 117, conduits for supply of air, e.g. pressurized air for pneumatic actuation systems, and electrical connections.

Electrical connections may, include, for example, any of power supplies, controls, and signal wiring. Drive unit 115 also includes a resin feed port 4076 (FIG. 41). Resin feed port 4076 receives a feed of molding material, e.g. pelletized molding material, and communicates with barrel unit 117 to supply molding material to the barrel. Service ports 4018 may be configured for quick connection to and disconnection from the corresponding ports of drive unit 115. In an example, service ports 4018 may couple using push-to-connect pneumatic or hydraulic connectors, magnetic connectors, barb fittings or the like. Thus, service ports 4018 may automatically connect or disconnect from the corresponding ports by application of force, e.g. due to movement of barrel unit 117, or in response to a control signal.

FIG. 4E depicts barrel unit 117, with coupling block 4010 and shroud 4008 removed to show internal features. Barrel unit 117 has a resin input port 4074 which communicates with the interior of barrel 4002 to deliver molding material to the interior of barrel 4002. Molding material is typically input to barrel 4002 in solid granular form and may be delivered, e.g. from a hopper (not shown). The hopper may be mounted to drive unit 115 or proximate drive unit 115 and deliver molding material to resin input port 4074 by way of a corresponding resin feed port 4076 on drive unit 115. In some embodiments, resin input port 4074 and resin feed port 4076 abut one another. In other embodiments, one of input port 4074 and feed port 4076 may be received within the other. In some embodiments, input port 4074 and feed port 4076 may be positively coupled to one another, for example, using quick connect fittings such as push-to-connect pneumatic or hydraulic connectors, magnetic connectors, barb fittings or the like. Connection and disconnection of such fittings may be automatically affected by application of force, e.g. due to movement of barrel unit 117, or in response to a control signal.

As best shown in FIG. 4F-4G, one or more locating devices may be provided to position drive unit 115 and barrel unit 117. The locating devices position barrel unit relative to drive unit 115 as the barrel unit is moved toward a coupling position. Specifically, the locating devices guide barrel unit 117 so that it seats against drive unit 115 in a coupling position, in which retention mechanism 4014 and drive mechanism 4016 can be engaged. That is, in the coupling position, components of the retaining mechanism 4014 and drive mechanism 4016 on barrel unit 117 align with the corresponding components on drive unit 115. The locating devices may progressively bias barrel unit 117 into its correct alignment as the barrel unit 117 is moved towards drive unit 115. In the depicted embodiment, the locating devices comprise leader pins 4020 and mating recesses 4022 (FIG. 4D). As shown, leader pins 4020 project from coupling block 4010 of barrel unit 117 and are received in recesses 4022 in frame member 4012 of drive unit 115.

Leader pins 4020 and recesses 4022 engage one another as barrel unit 117 is moved toward drive unit 115. Such engagement aligns barrel unit 117 relative to drive unit 115 such that the barrel unit 117 and drive unit 115 can be coupled by actuation of retaining mechanism 4014. In the depicted example, the alignment devices engage one another prior to engagement of the coupling system.

FIG. 4F1 depicts retaining mechanism 4014 in greater detail. In the depicted embodiment, retaining mechanism 4014 includes a stud 4024 and a socket 4026 which can selectively interlock with stud 4024. As shown, stud 4024 is part of barrel unit 117 and socket 4026 is part of drive unit 115. Stud 4024 may, for example, be threaded to coupling block 4010. Socket 4026 may be a recess cut into frame 4012 or an insert attached (e.g. threaded) to frame 4012.

Flowever, socket 4026 may instead be part of barrel unit 117 and stud 4024 may instead be part of drive unit 115.

Stud 4024 has inner and outer flanges 4028, defining a channel 4032 therebetween. Socket 4026 has an opening 4034, sized to receive stud 4024, and a gripping device 4036. Gripping device 4036 is configured for reception in channel 4032, in interlocking engagement with flanges 4028.

Gripping device 4036 is movable between engaged and disengaged states. In the disengaged state, gripping device 4036 clears flanges 4028 of stud 4024 such that stud 4024 may be freely inserted in or withdrawn from socket 4026. In the engaged state, gripping device interlocks with stud 4024, preventing stud 4024 from being withdrawn from socket 4026.

In the depicted embodiment, gripping device 4036 comprises a series of balls 4038 and a movable locking collar 4040. In the engaged state, locking collar 4040 holds balls 4038 against channel 4032. Balls 4038 bear against the distal flange 4028 of stud 4024, urging stud 4024 (and barrel unit 117) against drive unit 115. In the disengaged state, locking collar 4040 is withdrawn, allowing balls 4038 to shift away from stud 4024.

As shown, locking collar 4040 is spring-biased to the engaged state. An actuator is provided to selectively overcome the spring bias and thereby release locking collar 4040 and balls 4038. In the depicted embodiment, the spring bias is overcome by pneumatic pressure provided by a retention control line 4044, which is controlled by a valve (not shown).

Drive mechanism 4016 is shown in detail in FIGS. 4I-4J. Drive mechanism 4016 includes a driveshaft 4050 driven by an electric motor (not shown). Driveshaft 4050 has an end with a

toothed connector, e.g. spline 4052. The connector interfaces with a mating connector of screw 116, namely, spline 4054. As shown, spline 4052 of drive unit 115 and spline 4054 of screw 116 interface by way of a spline insert 4056.

Spline insert 4056 mates to both of splines 4052, 4054. Spline insert 4056 is movable along the axis of rotation of driveshaft 4050, between an engaged position and a retracted position.

In the engaged position, spline insert 4056 meshes with splines 4052, 4054 and rotationally couples driveshaft 4050 and screw 116. In the retracted position, spline insert 4056 is retracted along the axis of driveshaft 4050, to disengage from spline 4054 of screw 116. Thus, in the retracted position of spline insert 4056, driveshaft 4050 and screw 116 are de-coupled from one another. Retraction of spline insert 4056 may occur without any movement of driveshaft 4050. That is, spline insert may move along a longitudinal axis relative to both of driveshaft 4050 and spline 4054 of screw 116 to disengage.

The position of spline insert 4056 is controlled by an actuator, namely, drive actuation assembly 4060. As shown, drive actuation assembly 4060 includes a pneumatic cylinder 4062. The piston of pneumatic cylinder 4062 is connected to spline insert 4056 by way of a link 4064. Movement of the piston through its stroke in a first direction moves spline insert 4056 to its engaged position. Movement of the piston through its stroke in the opposite direction moves spline insert 4056 to its disengaged position.

A shroud is also coupled to link 4064 and moves along with link 4064 and spline insert 4056. In the engaged position, the shroud is positioned around the mating interface between spline insert 4056 and spline 4054 of screw 116. The shroud guards against ingress of objects or contaminants such as dust or other particulates, which may cause premature wear or reduced performance of the splines 4052, 4054.

Splines 4052, 4054 and spline insert 4056 define mating interfaces, namely interfaces between mating teeth at which torque can be transferred. The mating faces have relatively large axial length, such that the mating interfaces can accommodate some movement of driveshaft 4050 and screw 116 along their longitudinal axes. In other words, screw 116 and driveshaft 4050 can shift axially relative to one another without interfering with meshing of splines 4052, 4054 and spline insert 4056.

Screw 116 is rotationally supported by a bearing 4070 which is in turn supported on coupling block 4010 by a flange 4071. A support ring 4072 is secured to screw 116 above bearing 4070, by press-fit or other suitable technique.

In operation, screw 116 may be vertically supported at least in part by friction between spline insert 4056 and spline 4054 and by pressure of molding material within barrel 114. In this condition, there may be clearance between support ring 4072 and bearing 4070. When operation is terminated, screw 116 may fall until support ring 4072 abuts bearing 4070. Support ring 4072 is positioned such that, when screw 116 falls in this manner, a clearance gap opens between the ends of screw 116 and drive shaft 4050. In this state, drive unit 117 may be moved without rubbing and consequent wearing of drive shaft 4050 and screw 116 against one another.

Conveniently, in the depicted embodiment, engagement and disengagement of drive mechanism 4016 and retaining mechanism 4014 may occur independently of one another. That is, drive mechanism 4016 may be engaged or disengaged without changing the state of retaining mechanism 4014. Engagement of drive mechanism 4016 occurs by movement along the longitudinal axis of screw 116, and barrel unit 117 is physically located relative to drive unit 115 by movement in a perpendicular direction. Likewise, physical fixation of barrel unit 117 to drive unit 115 occurs by clamping in a direction perpendicular to the axis of screw 116, i.e. in a direction perpendicular to that in which engagement of drive mechanism 4016 occurs. Alignment of barrel unit 117 relative to drive unit 115 also occurs by movement along an axis perpendicular to that of screw 116. That is, leader pins 4020 extend in a direction perpendicular to the axis of screw 116. Independent operation of drive mechanism 4016 and retaining mechanism 4014 could also be achieved in other configurations. For example, the mechanisms could be configured to engage by movement along parallel axes, but the movements could be independent of one another.

Coupling block 4010 comprises at least one mating surface 4076. When barrel unit 117 is coupled to drive unit 115, mating surface 4076 abuts a corresponding face of drive unit 115 (i.e. a corresponding face of frame 4012). Mating surface 4076 may bear against frame 4012 to hold barrel unit 117 square to drive unit 115.

In some embodiments, mating surface 4076 may be located so as to limit stress on drive mechanism 4016. For example, as shown in FIG. 4F, mating surface 4076 is located at a central plane C of coupling block 4010. Longitudinal axis L of screw 116 lies within central plane C.

In operation, forces may be exerted on the tip of barrel 114. Such forces may include axial forces, i.e. forces parallel to longitudinal axis L, and transverse forces perpendicular to longitudinal axis L. Transverse forces may for example be caused by misalignment. The length of barrel 114 may act as a moment arm, such that transverse forces exert torque on barrel 114.

Contact between mating surface 4076 and frame 4012 may resist torque on barrel 114. That is, frame 4012 may exert reaction forces on mating surface 4076 which resist movement or twisting of barrel unit 117.

Alignment of plane C and longitudinal axis L may limit stress on barrel 114 and on spline 4054. Conversely, if place C and longitudinal axis L were spaced apart, transverse forces could also act around a secondary moment arm, perpendicular to longitudinal axis L. Alignment of mating face 4076 and longitudinal axis L avoids such secondary moment arms and therefore limits the torque to which spline 4054 and barrel 114 may be subjected.

Coupling block 4010 has a rear surface 4078 opposite mating surface 4076. When barrel unit 117 is coupled to drive unit 115, rear surface 4078 faces outwardly, away from drive unit 115. At least one pull stud 4080 is fixedly attached (e.g. threaded) to coupling block 4010. Each pull stud 4080 protrudes from coupling block 4010 for engagement by a removal tool to remove barrel unit 117 from drive unit 115.

FIG. 4K shows an example removal tool 4082. Removal tool 4082 is an automated (e.g. robotic) transportation device. Removal tool 4082 has a base 4084 and a rack 4086 supported on the base. Rack 4086 has a plurality of nests 4088, each capable of engaging and retaining a barrel unit 117. Two nests 4088-1 and 4088-2 are shown in FIG. 4K. However, any number of nests may be present.

Each nest 4088 has one or more couplings 4090 operable to selectively engage pull studs 4080. In some embodiments, couplings 4090 may be identical to gripping devices 4036 of drive unit 115 and pull studs 4080 may be identical to studs 4024 of barrel unit 117. Couplings 4090 are controlled by actuators (not shown). The actuators may be, for example, electronic, pneumatic or hydraulic actuators.

Rack 4086 may be mounted to base 4084 with a movable arm 4092. Arm 4092 is operable to extend to engage a barrel unit 117 for removal from drive unit 115, and to retract for transportation once the barrel unit is secured in a nest 4088. Arm 4092 may, for example, be drive by an electric servomotor or by a hydraulic or pneumatic cylinder.

As noted, plastic molding system 100 may include a plurality of barrel units 117, which may be interchangeably mountable to one or more drive units 115. For example, each barrel unit 117 may contain a different type of molding material, such as a different resin type different colour of material or the like.

Interchangeability of barrel units 117 may allow for rapid setup of molding system 100 to produce a specific variety of molded part. Removal tool 4082 may allow for automated changing of barrel units 117 at a drive unit 115. That is, removal tool 4082 may be capable of automatically approaching a drive unit 115, engaging a barrel unit 117 installed at that drive unit 115, removing the barrel unit 117 and retaining it, and installing a new barrel unit 117. Removal tool 4082 may then be capable of automatically transporting the removed barrel unit to a storage or cleaning area.

FIGS. 4L-40 depict a process of installing a barrel unit 117 to a drive unit 115.

As shown in FIG. 4L, a barrel unit 117 is carried by removal tool 4082 to a position facing drive unit 115. In some embodiments, removal tool 4082 may be guided into position relative to drive unit 115. For example, a beacon, such as an infra-red or other light-based beacon, or a radio frequency (RF) beacon may be installed at drive unit 115 or barrel unit 117 and corresponding sensors may be installed at removal tool 4082. Removal tool 4082 may be programmed to detect signals from the beacon and move toward the detected signals. In other embodiments, removal tool 4082 may be programmed to monitor and record its position. For example, removal tool 4082 may initially be manually moved into position at a particular drive unit 115 and may record coordinates corresponding to that position. Thereafter, on receipt of a specific instruction, removal tool 4082 may automatically return to the recorded position. In some embodiments, removal tool 4082 may be programmed in this manner to retain a number of transfer positions, each for engaging with a respective drive unit 115.

With removal tool 4082 aligned with drive unit 115, arm 4092 is extended to move the barrel unit 117 towards drive unit 115.

As barrel unit 117 approaches drive unit 115, gripping devices 4036 of barrel unit 117 are opened. In the depicted embodiment, opening of gripping devices 4036 entails energizing the gripping device to overcome a spring bias towards the closed state. Energizing may be by providing a stream of pressurized air or water, or by an electrical signal.

Alignment devices on the barrel unit 117 and drive unit 115 engage one another to position barrel unit 117 relative to drive unit 115. Specifically, leader pins 4020 are received in recess 4022 and guide barrel unit 117 onto drive unit 115.

As shown in FIG. 4M, stud 4024 is received in socket 4026. The tapered leading end of stud 4024 may bear against walls of socket 4026 or against gripping device 4036 to provide fine alignment of stud 4024.

What barrel unit 117 is being installed, screw 116 is supported by support ring 4072 resting atop bearing 4070. In this condition, with barrel unit 117 positioned so that stud 4024 aligns with socket 4026 of drive unit 115, a clearance gap exists between the ends of screw 116 and drive shaft 4050. Thus, as barrel unit 117 is moved into position, screw 116 passes below drive shaft 4050 and spline insert 4056 without contacting either the drive shaft or the spline insert.

As shown in FIG. 4N, Barrel unit 117 is moved towards drive unit 115 until stud 4024 is fully received within socket 4026. The retaining actuator is activated to close gripping device 4036, thereby locking stud 4024 and barrel unit 117 in place relative to the drive unit 115. Engagement of stud 4024 by gripping device 4036 pulls stud 4024 and barrel unit 117 towards drive unit 115. With stud 4024 so engaged, mating surface 4076 of coupling block 4010 is clamped tightly against drive unit 115. In some embodiments, gripping device 4036 remains closed, engaging stud 4024 unless energy is applied to release it, for example, in the form of hydraulic or pneumatic pressure.

As shown in FIG. 40, with barrel unit 117 physically fixed to drive unit 115, drive mechanism 4016 may be activated to rotationally couple screw 116 to a motor by way of drive shaft 4050. A signal is provided to drive actuation assembly 4060, causing pneumatic cylinder 4062 to extend and move spline insert 4056 to its engaged position. Extension of spline insert 4056 causes spline insert 4056 to mesh with spline 4054, thereby rotationally coupling screw 116 to drive shaft 4050 and the motor driving drive shaft 4050.

FIGS. 4P-4R and 4S depict a process of removing a barrel unit 117 from a drive unit 115.

As shown in FIG. 4P, drive actuation assembly 4060 disengages drive mechanism 4016 prior to movement of barrel unit 117. Drive actuation assembly 4060 receives a signal causing retraction of cylinder 4062 and thus, of spline insert 4056. Retraction of spline insert 4056 releases the mesh between spline insert 4056 and spline 4054 so that screw 116 and drive shaft 4050 can rotate independently of one another.

Screw 116 may fall so that support ring 4072 supports drive screw 116 on bearing 4070. Screw

116 may fall immediately after retraction of spline insert 4056, or after pressure of molding material within barrel 114 is reduced. When supported by support ring 4072 on bearing 4070, and with spline insert 4056 retracted, screw 116 does not contact drive shaft 4050 or spline insert 4056 and barrel unit 117 is clear of drive shaft 4050 and spline insert 4056 for removal.

As shown in FIG. 4S, removal tool 4082 approaches barrel unit 117 and arm 4092 extends into contact or nearly into contact with barrel unit 117.

Gripping devices 4036 of drive unit 115 are energized so that they release stud 4024. Couplings 4090 of removal tool 4082 are positioned on pull stud 4080 of barrel unit 117 and are locked in a closed position engaging the pull studs. Locking of couplings 4090 holds the barrel unit 117 to nest 4088 and to rack 4086 of removal tool 4082.

With barrel unit 117 locked to arm 4092, removal tool 4082 retracts the arm to pull barrel unit

117 away from drive unit 115. Stud 4024 is withdrawn from socket 4026 and service ports 4018 and resin input port 4076 decouple from the corresponding ports of drive unit 115. The alignment mechanism also decouples, as leader pins 4020 are withdrawn from recesses 4022 (not shown).

After barrel unit 117 is removed from drive unit 115, a new barrel unit may be installed. In some examples, removal tool 4082 moves the new barrel unit into alignment with drive unit 115. Specifically, removal tool 4082 may shift a nest 4088 carrying the new barrel unit into alignment with drive unit 115.

With the new barrel unit aligned, removal tool 4082 extends arm 4092 to couple the new barrel unit to drive unit 115, as described above with reference to FIGS. 4L-40.

In some examples, the removed barrel unit 117 may remain in its nest 4088 on arm 4092 while a new drive unit at another nest 4088 is installed to drive unit 115. Removal tool may arrive at drive unit 115 carrying a first barrel unit, and may automatically remove a second barrel unit from the drive unit 115 and replace the second barrel unit with the first barrel unit.

Upon removal from drive unit 115, a barrel unit may be stored. The barrel unit may, for example, be transferred from the removal tool 4082 to a rack or other storage area. Alternatively, the barrel unit may simply remain on the removal tool 4082 for storage. In some examples, a plurality of removal tools 4082 may be present, and each stored barrel unit may be stored on a removal tool having at least one vacant nest 4088. Accordingly, any stored barrel unit could be installed by sending its respective removal tool to a drive unit, and the removal tool would also be capable of removing the previous barrel unit from the drive unit.

Interchangeability of barrel units 117, and particularly, automated interchangeability, may allow for rapid configuration and reconfiguration of molding system 100. In particular, different barrel units may be used with different molding materials, e.g. different material types or colours. Molding system 100 can therefore be reconfigured for molding parts of different materials by simply swapping barrel units 117.

Transport Vessels

Details of transport vessels in which molten feedstock may be moved between process stations, as associated features at process stations will now be described, with primary reference to FIGS. 5-12.

FIG. 5 is an enlarged cross-sectional view of an extruder 112 and vessel 124 depicting components in greater detail.

Feedstock such as PET pellets is introduced into the cavity of barrel 114 and is urged toward outlet orifice 122 by rotation of screw 116. Rotation of screw 116 compresses the feedstock and thereby causes heating and ultimately melting of the feedstock for dispensing into a vessel 124.

Extruder 112 includes a nozzle assembly 113 positioned at the dispensing end of barrel 114. As will be explained in further detail, a vessel 124 may be positioned opposite nozzle assembly 113 to receive molten feedstock. A gate assembly 1130 may be interposed between the extruder and nozzle assembly.

In some embodiments, only a subset of available extruders may be installed at any given time. For example, molding system 100 may have four or more extruders 112 available for use, only a subset of which may be installed or in active use at any given time.

In such embodiments, each extruder 112 may be used with a specific feedstock (e.g. a specific combination of colour and material). Conveniently, this may reduce or eliminate the need to change feedstock in any given extruder 112. That is, a switch from a first to a second feedstock may be accomplished by removing an extruder containing the first feedstock and replacing it with another extruder containing the second feedstock. Optionally, the first feedstock may be left in its extruder 112 for the next time that feedstock is needed. Alternatively, the extruder may be subjected to a cleansing process, which may be automated, to remove the first feedstock and ready the extruder for its next use.

In contrast, changing a feedstock within a specific extruder 112 is relatively difficult, time consuming, expensive (wasted molding material) and labour intensive. Typically, the existing feedstock must be thoroughly purged from the extruder before a new feedstock can be introduced.

Vessel 124 is carried by transport subsystem 110 and is positioned adjacent extruder 112 to receive molten feedstock. In the depicted embodiment, vessel 124 is a cartridge with an outer wall 132 defining an internal cavity 134. Outer wall 132 may be insulated, or may be formed of a material with relatively high thermal resistance. In some embodiments, temperature control elements, such as heating and/or cooling devices, may be mounted to or integrated with wall 132 for maintaining thermal control of feedstock within internal cavity 134.

Vessel 124 may be thermally conditioned such that, prior to receiving molten feedstock, the vessel has a thermal profile consistent with a desired feedstock temperature. For example, vessel 124 may be heated prior to receiving feedstock, to limit head loss from the feedstock to vessel

124.

A buffering area may be defined, e.g. within or proximate dispensing cell 102, in which one or more vessels 124 may be collected and prepared for receiving feedstock, e.g. by thermal conditioning such as heating. Vessels may be carried to and from the buffering area by transport subsystem 110.

FIGS. 6A and 6B depict isometric and cutaway isometric views, respectively, of a vessel 124. The vessel has a gate orifice 136 designed to matingly engage outlet orifice 122 of extruder 112 to receive flow therefrom. As further described below, in the depicted embodiment, gate orifice 136 also mates to a mold of a shaping station 104-1, 104-2,...104-8 to deliver molten feedstock into the mold. In other embodiments, a separate orifice may be provided for permitting feedstock to exit vessel 124. In such embodiments, vessel 124 may be configured so that feedstock is handled in a first-in first-out manner. That is, the first feedstock that enters vessel 124 through gate orifice 136 may also be the first feedstock that is pushed out of vessel 124 through an exit orifice. This may limit degradation of material within vessel 124.

Vessel 124 comprises a barrel 1320 and a tip 1322. Tip 1322 fits over and seals with an end portion of barrel 1320 and the barrel and tip cooperate to define inner cavity 134. Barrel 1320 and tip 1322 may be formed of different materials. For example, barrel 1320 may be formed of an alloy with high surface hardness for durability. Tip 1322 may be formed of an alloy with high thermal conductivity.

A sealing member 140 (FIG. 6B) is positioned within cavity 134. Sealing member 140 is operable to control flow through the gate orifice 136. Sealing member 140 is sized to occlude and substantially seal one or both of extruder outlet orifice 122 and vessel gate orifice 136. As depicted, sealing member 140 has a shoulder 1402 that contacts and forms a seal with a corresponding shoulder 1404 of the internal wall of tip 1322. Thus, sealing member 140 and tip 1322 may seal against one another with axial facing surfaces, rather than, or in addition to, sealing between complementary circumferential surfaces of the vessel gate orifice 136 and an end portion of the sealing member 140. Such axial sealing may be less prone to leakage and wear.

Sealing member 140 includes an elongate stem, also referred to as a valve stem, which is axially moveable relative to the gate orifice 136. Sealing member 140 may be moved by manipulation of the stem. Specifically, sealing member 140 may be retracted away from gate orifice 136 to permit flow therethrough, or may be extended to occlude and seal gate orifice 136. In some embodiments, when fully extended, sealing member 140 may protrude from vessel 124 and into outlet orifice 122 of extruder 112. In such embodiments, sealing member 140 may form seals with both of orifices 136 and 122.

Vessel 124 also includes an ejection mechanism for forcing material out of cavity 134. As depicted, the ejection mechanism includes a piston 182 received within cavity 134 and movable within the cavity between an extended position in which piston 182 is proximate orifice 136, and a retracted position (shown in FIG. 6B) in which piston 182 is displaced away from orifice 136 and cavity 134 is occupied by molding material. Piston 182 is configured to seal against the inner wall of vessel 124 as the piston moves between its extended and retracted positions. Thus, piston 182 may scrape molding material from the inner wall as it moves toward orifice 136.

A thermal regulating assembly 1324 may be positioned over at least a portion of barrel 1320 and tip 1322. As depicted, thermal regulating assembly 1324 includes a metallic sleeve 1326 and a heating device, namely, heating coil 1328.

In the depicted embodiment, sleeve 1326 is a thermal insulator and inhibits heat loss through underlying surfaces of barrel 1320 and tip 1322. Sleeve 1326 may, for example, be formed of an alloy with relatively low thermal conductivity. In other embodiments, sleeve 1326 may serve as a heat sink, such that it tends to promote heat transfer out of molding material within cavity 134.

Heating coil 1328 is configured to selectively introduce heat into barrel 1320 and tip 1322, and thereby, into molding material within cavity 134. Heating coil 1328 may be provided with contacts 1330, which may be external to sleeve 1326. Contacts 1330 are configured to interface with an external power source to activate heating coil 1328. The external power source may be provided at discrete locations. For example, contacts 1330 may connect with corresponding contacts at a station of dispensing cell 102, shaping cells 104, 106 or conditioning cell 108, or at a heating station between stations of cells 102, 104, 106, 108. Alternatively, contacts 1330 may interface with corresponding power lines along the length of track 144 such that vessel 124 is heated continuously or throughout a portion of its travel between stations.

Sleeve 1326 and heating coil 1328 may be configured to produce a desired thermal profile in molding material within cavity 134. Sleeve 1326 is positioned proximate tip 1322 and the inlet end of barrel 1320, and extends toward the base of vessel 124, i.e. toward the retracted position of piston 182. In some embodiments, sleeve 1326 does not reach to the retracted position of piston 182. That is, in some embodiments, in the retracted position of piston 182, sleeve 1326 does not overlie piston 182 or the portion of barrel 1320 that surrounds the piston 182.

In an alternative embodiment, not shown, heating of the vessel 124 may be indirect. For example, the vessels 124 may be induction heated, wherein the vessel includes a heating jacket formed of a suitable material, e.g. brass, aluminum, copper or steel, for coupling with an applied electromagnetic field emanating from a coil located at a heating station or otherwise arranged along a path of travel.

In the depicted embodiment, vessel 124 has an insulator 1332 positioned at the end of tip 1322. A cap 1334 fits tightly over insulator 1332. Orifice 136 is cooperatively defined by holes in tip 1322, insulator 1332 and cap 1334, which align with one another are which are sized to receive sealing member 140.

Insulator 1332 is formed of a material selected for sufficient mechanical strength and low thermal conductivity and may be, for example, plastic, ceramic or metallic. Cap 1334 is formed of a material selected for relatively high thermal conductivity. As will be explained in further detail, cap 1334 interfaces with a mold plate of a station of shaping cell 104, such that cap 1334 is interposed between the mold and tip 1322 of vessel 124. High thermal conductivity of cap 1334 promotes heat transfer from the cap to the mold. Thus, cap 1334 tends to be cooler than tip

1322. Cap 1334 cools the distal tip of sealing member 140, which in turn promotes solidification of molding material. Thus, at the end of an injection operation, the relatively cool cap 1334 and sealing member 140 tend to promote solidification of residual material in orifice 136. Such solidification may allow for clean parting of molded articles. Insulator 1332 tends to inhibit heat transfer between tip 1322 of vessel 124 and mold. Thus, the portion of tip 1322 and insulator 1332 that surround orifice 136 may remain at a temperature close to that of the molten molding material, such that the molding material experiences a large temperature gradient upon passing through cap 1334. In some embodiments, cap 1334 may have an internal profile configured to limit surface area of contact between cap 1334 and tip 1322. For example, cap 1334 may have ridges or castellation (not shown) to locate cap 1334 relative to tip 1322 without continuous contact between components.

Tip 1322, insulator 1332, cap 1334, orifice 136 and sealing member 140 cooperatively define a coupling assembly for mating of vessel 124 to stations of the dispensing and shaping cells. External features such as the outer diameter of cap 1334 and the shoulder of tip 1322 engage with corresponding locating features of the shaping or injecting station to position orifice 136 in alignment with a mold or extruder. The coupling assembly may also serve to seal vessel 124, e.g. by sealing member 140 sealing orifice 136.

In the depicted embodiment, transport subsystem 110 comprises a track 144. Vessel 124 is received in a carriage 125, which is slidably received on the track 144. Vessel 124 and carriage 125 may be moved along the tracks, e.g. by pneumatic or electromagnetic manipulation, or by a mechanical device such as a belt or chain. Transport subsystem 110 is capable of precisely indexing the position of each carriage 125 mounted to track 144. Thus, transport subsystem 110 may align a specific carriage 125 and vessel 124 with a specific extruder 112, such that gate orifice 136 of vessel 124 aligns with outlet orifice 122 of extruder 112.

Vessel 124 is movable with carriage 125, towards or away from extruder 112. In the depicted embodiment, movement of vessel 124 within carriage 125 is in a direction perpendicular to track 144. Carriage 125 may have a channel that defines a seat for the vessel and for otherwise defining a path of motion of vessel 124.

Movement of vessel 124 within carriage 125 and operation of sealing member 140 are effected by an actuator assembly 172.

Actuator assembly 172 includes a vessel positioning actuator, a piston actuator 176 and a sealing member actuator 178.

With vessel 124 in a dispensing (i.e. filling) position aligned with extruder 112, the vessel positioning actuator is likewise aligned with vessel 124 and is operable to extend into contact with vessel 124 and urge the vessel 124 into engagement with nozzle assembly 113 of extruder 112. So engaged, the outlet orifice 122 of extruder 112 and the gate orifice 136 of vessel 124 align in fluid communication with one another.

A piston 182 is movable by piston actuator 176 between an empty position in which piston 182 is located proximate orifice 136 and a filled position, in which piston 182 is displaced by feedstock within cavity 134. Piston 182 is biased towards its empty position, for example, by a spring or by mechanical force from actuator assembly 172.

Sealing member actuator 178 is operable to engage and retract sealing member 140 from gate orifice 136, thereby permitting flow of molten feedstock through gate orifice 136 and into cavity 134 of vessel 124. In the depicted embodiment, sealing member 140 includes a detent 180 for gripping by sealing member actuator 178, such that sealing member actuator 178 can push sealing member 140 into sealing engagement with gate orifice 136 or withdraw the sealing member 140 to permit flow.

FIGS. 7A-7B show isometric views of vessel 124 and carriage 125. Carriage 125 has a base 1250 configured for mounting to track 144 and a retaining mechanism 1252 for releasably engaging vessel 124 to hold the vessel 124 to the base 1250.

Retaining mechanism 1252 has grips, e.g. tongs 1254 configured to securely hold vessel 124. In the depicted embodiment, retaining mechanism 1252 includes two sets of tongs 1254. Flowever, more or fewer sets may be present. Tongs 1254 are mounted to a carrier plate 1262, which is in turn mounted to base 1250.

Tongs 1254 are movable between an open position (FIG. 7 A) and a closed position (FIG. 7B). In the closed position, tongs 1254 retain vessel 124. Such retention may be achieved, for example, by friction or by interlocking or a combination thereof. In the depicted embodiment, one set of tongs 1254 interlocks with a corresponding detent 1255 in the surface of vessel 124. A second set of tongs 1254 frictionally grips an outer surface of the barrel 1320 of vessel 124. The second set of tongs 1254 is positioned above a second detent 1256 in vessel 124. As explained in detail below, detent 1256 is for engaging a locating feature at a processing station. Tongs 1254 are therefore positioned to avoid interfering with the locating feature. In the open position, clearance is provided between tongs 1254 and vessel 124, such that vessel 124 can freely pass between or be removed from tongs 1254.

Tongs 1254 may be biased toward a closed position. For example, tongs 1254 may be biased by a spring assembly 1260. In some embodiments, spring assembly 1260 may be double-acting such that, when tongs 1254 are partially opened, e.g. by a threshold amount, spring assembly 1260 instead biases tongs 1254 to the open position. Tongs 1254 may be configured so that insertion of vessel 124 between tongs 1254 toggles tongs 1254 to their closed position. For example, tongs 1254 may have a profile such that insertion of vessel 124 moves the tongs to an intermediate position between the open and closed positions, in which spring assembly 1260 biases tongs 1254 to snap to the closed position. The profile of tongs 1254 may be such that they tend to center vessel 124 as it is inserted between the tongs. Thus, some horizontal misalignment of vessel 124 may be tolerated and corrected during seating of the vessel inside tongs 1254 and closing of the tongs.

Tongs 1254 and carrier plate 1262 are suspended on base 1250 such that they have some vertical freedom of movement relative to base 1250. For example, tongs 1254 may be free to move vertically to align with detent 1255. Such freedom of movement may compensate for vertical mis-alignment of vessel 124.

Carrier 125 further includes a closure assembly 1270. In the embodiment of FIGS. 7A-7B, closure assembly 1270 is mounted proximate the bottom of base 1250.

Closure assembly 1270 has a movable arm 1272, which is movable between a sealing position, shown in FIGS. 7A-7B and an open position. In the embodiment of FIGS. 7A-7B, in the sealing position, arm 1272 contacts an end of sealing member 140 and urges it upwardly toward tip 1322 of vessel 124 to seal orifice 136.

Referring to FIGS. 8A-8D, a sequence of operations for dispensing feedstock from extruder 112 to vessel 124 is shown in detail. FIG. 8 A shows a side elevation view of part of extruder 112 and vessel 124 prior to engagement thereof. FIG. 8B shows a side elevation view of extruder 112 and vessel 124 after engagement and just prior to dispensing of feedstock. FIGS. 8C-8D show longitudinal cross-sectional views of extruder 112 and vessel 124 prior to and during dispensing.

As shown in FIG. 8A, vessel 124 is held in a carriage 125, movably mounted on track 144. Carriage 125 and vessel 124 are moved on track 144, into a dispensing position, between a dispensing nozzle of extruder 112 and actuator assembly 172. The vessel positioning actuator (not shown) extends to move vessel 124 into abutment with nozzle assembly 113 of extruder

112, as shown in FIG. 8B.

As shown in FIG. 8C, sealing member actuator 178 retracts sealing member 140 to permit flow of feedstock from extruder 112 into vessel 124. Piston 182 is displaced away from extruder 112, increasing the volume of cavity 134, as molten feedstock flows into vessel 124. In the depicted embodiment, vessel 124 has a stop (not shown) which limits displacement of piston 182 and thereby controls the amount of feedstock that is permitted to flow into vessel 124. The stop may be adjustable. Alternatively, extruder 112 may include a metering mechanism. For example, the extruder 112 may include a pumping device for dispensing a specific preset volume of feedstock. Screw 116 may itself function as such a pumping device. For example, rotation of screw 116 may be controlled to dispense a specific volume. Alternatively, screw 116 may be axially translated to dispense a specific volume.

A dose of feedstock is deposited in vessel 124. The dispensed dose may be referred to as a workpiece 101. As used herein, workpiece 101 refers to a dose of feedstock throughout its processing in system 100. Primes of the workpiece, i.e. 101’, 101” denote changes in form of the feedstock dose as it is processed.

When filling of vessel 124 is complete, sealing member actuator 178 extends sealing member 140 to seal gate orifice 136, as shown in FIG. 8C. The vessel positioning actuator then retracts and vessel 124 moves away from extruder 112 and into carriage 125.

A vessel 124 filled with feedstock material may be transported to a shaping station of shaping cell 104 for a molding operation.

In some embodiments, a gate assembly 1130 may be interposed between nozzle assembly 113 and vessel 124. FIG. 9 shows an exploded view of nozzle assembly 113 and vessel 124 with gate assembly 1130. The gate assembly has particular utility when used in combination with a vessel without a sealing member 140 (FIG. 8B). Gate assembly 1130 may serve to locate orifice 136 of vessel 124 with nozzle assembly 113. Gate assembly 1130 may further serve to cut a stream of feedstock between nozzle assembly 113 and vessel 124 when filling of vessel 124 is complete.

Gate assembly 1130 includes a guide block 1132 and a blade 1134. Guide block 1132 has respective recesses 1136 for receiving and aligning each of nozzle assembly 113 and the tip of vessel 124. Blade 1134 can be extended through a pocket in guide block to cut off a stream of feedstock. As depicted, blade 1134 has an arched cross-sectional shape and is compressed within the pocket of guide block 1132 such that blade 1134 is biased against nozzle 113. A scraper 1133 is positioned opposing blade 1134, such that scraper 1133 contacts blade 1134 to dislodge molding material from the blade.

Blade 1134 may be extended to cut off a stream of feedstock when filling of vessel 124 is complete. FIGS. 10A-10B are enlarged cross-sectional views of nozzle assembly 113, vessel 124 and gate assembly 1130 during cutting of a feedstock stream.

As shown in FIG. 10A, a stream of feedstock is dispensed from nozzle assembly 113 into vessel 124 through orifice 136. When filling of vessel 124 is complete, blade 1134 is advanced toward the stream.

As shown in FIG 10B, blade 1134 is biased against nozzle assembly 113. As blade 1134 is advanced into the feedstock stream, blade 1134 parts the stream. Blade 1134 fits tightly against nozzle assembly 113 such that feedstock is substantially prevented from leaking between blade 1134 and nozzle assembly 113. Blade 1134 has a tab 1138 which extends downwardly into contact with vessel 124. As blade 1134 advances across vessel 124, tab 1138 scrapes feedstock away to limit or eliminate residue on the exterior of the vessel.

Primary Shaping

With primary reference to FIGS. 11-24, features and operation of example stations of shaping cell 104 will now be described in detail. In the depicted embodiments, the example stations are for injection molding of plastic articles. Flowever, many features of the described embodiments are not limited to injection molding, as will be apparent.

FIGS. 11-12 show an enlarged isometric view and a side cross-sectional view, respectively, of a shaping station 104-1 of shaping cell 104. Shaping station 104-1 cycles between an open state for discharging a molded workpiece and a closed state for receiving a dose of feedstock to form a molded workpiece 101’. As shown in FIGS. 11-12, shaping station 104-1 is in an open state.

Shaping station 104-1 has a mold defined by a core assembly 190 and a cavity assembly 192. Cavity assembly 192 has two cavity plates 194-1, 194-2 (individually and collectively, cavity plates 194), mounted to platens 196-1, 196-2 (individually and collectively, platens 196). Platen 196-1 is mounted to a clamping mechanism, such as a hydraulic or electro-mechanical piston.

Platen 196-1 is movable relative to platen 196-2, the latter of which is fixedly mounted to a base structure.

As shown in FIG. 12A, in the open state of shaping station 104-1, platen 196-1 is withdrawn from platen 196-2. Cavity plate 194-2 is aligned with a mold axis M-M and core assembly 190 is aligned with an ejection axis E-E.

FIGS. 12B-12D depict components of shaping station 104-1 in greater detail. In the depicted example, shaping station 104-1 includes a mold subassembly 3040, a clamp subassembly 3042 and a core actuation subassembly 3044, the latter of which includes a core positioning actuator 3046 and a load actuator 3050. For simplicity, core actuation assembly is omitted from FIG. 12D.

Each of mold subassembly 3040, clamp subassembly 3042 and core actuation subassembly 3044 are mounted to a shaper frame 3052. Mold subassembly 3040, clamp subassembly 3042, core actuation subassembly 3044 and shaper frame 3052 collectively define a shaper module 3054. The shaper frame 3052 may be removably mounted to a support base 3056 of shaping station 104-1, such that shaper module 3054 may be installed or removed as a unitary assembly.

As best shown in FIG. 12C, mold subassembly 3040 may be opened and closed along multiple axes. That is, platens 196, with cavity plates 194, may be opened and closed along a clamping axis Cl -Cl. Core assembly 190 may be moved towards or away from cavity plates 194 along core axis C2-C2. Opening and closing along clamping axis Cl-Cl may be affected by clamp subassembly 3042. Movement of core assembly 190 along core axis C2-C2 may be affected by core actuation subassembly 3042.

FIG. 12D shows details of coupling between clamp subassembly 3042 and shaper frame 3052. For simplicity, core actuation subassembly 3044 is omitted from FIG. 12D.

Platens 196 may be supported by shaper frame 3052. Platens 196 and shaper frame 3052 may have mating guide features which maintain position and alignment of platens 196 during opening and closing. In the depicted embodiment, the guide features include guide rails 3062 on shaper frame 3052 which matingly receive pins (not shown) on platens 196. In other embodiments, the guide features may be interlocking tracks. Other guide structures are possible, as will be apparent.

As depicted, platen 196-1 is slidably mounted to support frame 3052 using the guide features. Platen 196-2 is rigidly mounted to support frame 3052 in a fixed position. In this embodiment, clamp subassembly 3042 causes opening and closing by movement of platen 196-1 relative to platen 196-2 along clamping axis Cl-Cl. In other embodiments, opening and closing is achieved by movement of both platens toward and away from one another.

Clamp subassembly 3042 includes a multi-bar linkage 3070. Linkage 3070 includes an anchor block 3072 rigidly mounted to support frame 3052, and a plurality of pivotably-connected links coupling a platen 196 to the anchor block 3072. In the depicted embodiment, the links include a drive link 3074 and first and second rockers 3076, 3078. Drive link 3074 is coupled to a crosshead 3080.

Crosshead 3080 may be reciprocated by a suitable linear actuator, such as a ballscrew. Drive link 3074 may pivot relative to crosshead 3080 and relative to rockers 3076, 3078 as the crosshead moves through its stroke, likewise causing rockers 3076, 3078 to pivot relative to one another to drive platen 196 in either direction along clamping axis C1-C2.

Clamp subassembly 3042 has a plurality of pivotable connections 3082, each of which may be formed by press-fitting a pin and a bushing (not shown) through holes in the links or in support frame 3052. Other connection types may be used, provided they have sufficient strength and provide adequate range of motion.

Anchor block 3072 is mounted to support frame 3052 such that the center axis of anchor block 3072 aligns with the center axis of support frame 3052. Guide rails 3062 maintain the position of platen 196 such that the center axis of platen 196 aligns with the center axis of support frame 3052. Thus, anchor block 3072 and platen 196 are coupled to linkage 3070 at the center axes of anchor block 3072, platen 196 and support frame 3052. In other words, pivotable connection 3082 between the anchor block 3072 and rocker 3076 is located along the center axis of anchor block 3072 and along the center axis of support frame 3052. Likewise, pivotable connection 3082 between platen 196 and rocker 3078 is located along the center axis of anchor block 3072 and along the center axis of support frame 3052.

Movement of crosshead 3080 causes platens 196 to move between open and closed positions. In the closed (molding) position, a clamping force may be applied through crosshead 3080 and linkage 3070 to urge the platens together. The clamping force may be substantial - in some embodiments, the clamping force may be on the order of 300 kN. As will be apparent, a reaction force is applied to support frame 3052. In the depicted embodiment, platen 196 and anchor block 3072 are loaded substantially in pure compression, and that support frame 3052 is loaded substantially in pure tension because linkage 3979 is coupled to platen 196 and anchor block 3072 at the center axis of platen 196, anchor block 3072 and frame 3052. In contrast, location of any of the pivotable connections away from the center of a given component could produce significant shear force or bending moment. For example, platens in conventional injection molding machines tend to be closed by rams (e.g. hydraulic rams or ball screws) positioned

proximate the corners of a platen. Exerting of clamping force in such configurations may produce a bending moment in the platens and may in some cases lead platens to deflect.

In some embodiments, the stroke length between the open and closed positions of platen 196 is relatively short. The length of the stroke is influenced by the amount of clearance required to remove (de-mold) a finished part. De-molding may be possible with a relatively small opening along an axis perpendicular to the longitudinal axis of the part. Thus, some example embodiments have a mold-opening stroke on the order of 60-120 mm. Conversely, if parts were to be de-molded by opening along the longitudinal axis of the part, a longer opening stroke may be required, to create a larger amount of clearance.

Other linkage configurations are possible. For example, in some embodiments, the linkage may include one or more rockers which are pivotably connected to support frame 3052. FIGS. 13A-13C show a linkage 3070’ exemplary of such a configuration.

Finkage 3070’ has a drive link 3074’ anchored to a linear actuator 3088 (as shown, a ball screw driven by an electric motor) with one or more intermediate links 3086. Drive link 3074 is mounted on a linear guide 3090. As depicted, the linear guide constrains drive link 3074’ to move in a single direction, namely, vertically. Specifically, linear actuator 3088 reciprocates horizontally, and intermediate links 3086 pivot to move the drive link through reciprocating vertical path I-I defined by linear guide 3090 (FIG. 13B).

Drive link 3074’ is pivotably connected to two rockers 3076’, 3078’ by way of further intermediate links 3086. Each rocker 3076’, 3078’ is mounted to a respective platen 196 for driving the platen through a reciprocating open-close motion. Each rocker 3076’, 3078’ is pivotably mounted to support frame 3052. Reciprocation of drive link in direction I-I (FIG. 13B) causes rockers 1-76’, 3078’ to pivot about their connection to support frame 3052, i.e. in direction II-II. Such pivoting in turn drives reciprocation of platens 196 along direction III-III. The position and orientation of platens 196 during such reciprocation is maintained by guide rails 3062 on support frame 3052.FIG. 13C shows an example loading state of linkage 3070’ and support frame 3052 when platens 196 are in a mold-closed position. As depicted, drive link 3074’ applies a force to rockers 3076’, 3078’. The rockers 3076’, 3078’ pivot to around their connections to drive platens 196 together and apply a clamping force against the platens. Because rockers 3076’, 3078’ pivot about their midpoints, the clamping force and the force applied by drive link 3074 are substantially equal in magnitude. Equal reaction forces are applied against rockers 3076’, 3078’, which are resisted by support frame 3052. Transfer of

forces between rockers 3076’, 3078’ and support frame 3052 occurs at pivotable connections 3082, which are located at the center axis of support frame 3052. Accordingly, application of clamping force loads support plate 3052 substantially in pure tension.

The length of the opening/closing stroke of platens may be determined by geometric specifications of linkage 3070’. Specifically, the stroke may be determined by a combination of the lengths of drive link 3074’, rockers 3076’, 3078’, intermediate link 3086, and the length of stroke of linear actuator 3088.

In some embodiments, the linkage may be configured to maintain position and alignment of platens 196 without the use of guiding structures such as guide rails 3082. FIGS. 14A-14B show an example of one such linkage 3070” .

Linkage 3070” is generally identical to linkage 3070’ , except that linkage 3070’’ further includes secondary rockers 3096, 3098, and that support plate 3052’ is somewhat larger than support plate 3052 in order to accommodate the extra rockers.

WHAT IS CLAIMED IS:

1. A method for use in molding articles, comprising:

moving a vessel for holding molten molding material along a track to a molten molding material dispensing cell;

dispensing a flowable molten molding material to said vessel at said molten molding material dispensing cell;

following said dispensing, moving said vessel along said track to a molding cell; at said molding cell, injecting said molten molding material from said vessel to a molder of said molding cell.

2. The method of claim 1 wherein said molding cell has a plurality of molders and further comprising, prior to said injecting said molten molding material from said vessel to said molder, selecting said molder from amongst said plurality of molders dependent upon a characteristic of said molten molding material dispensed to said vessel at said molten molding material dispensing cell.

3. The method of claim 2 wherein said characteristic is a volume of said molten molding material dispensed to said vessel.

4. The method of any one of claim 1 to claim 3 wherein said vessel is one of a plurality of vessels and further comprising:

tracking a position of each vessel.

5. The method of claim 4 wherein said molten molding material dispensing cell has a

plurality of dispensers, and said molding cell has a plurality of molders and further comprising:

moving said each vessel to a selected dispenser of said molten molding material dispensing cell to receive molten molding material, and

moving said each vessel to a selected molder of said molding cell dependent upon a characteristic of molten molding material dispensed to said each vessel.

6. The method of claim 5 wherein said characteristic is a composition of said molding material.

7. The method of claim 6 wherein said composition comprises a colorant.

8. The method of claim 6 wherein said composition is a thermoplastic or a thermoset plastic resin.

9. The method of any one of claim 1 to claim 8 further comprising, following said injecting said molten molding material to said molder, returning said vessel along a return line of said track back toward said molten molding material dispensing cell.

10. The method of claim 5 further comprising, following injecting said molten molding material from each said vessel, returning each said vessel along a return line of said track back toward said molten molding material dispensing cell.

11. The method of claim 10 wherein said selected dispenser is selected based on said

characteristic of molten molding material dispensed to said each vessel when said each vessel was previously at said molten molding material dispensing cell.

12. The method of claim 10 further comprising transferring articles molded at said molding cell to said return line of said track.

13. The method of claim 12 further comprising transferring articles on said return line of said track to selected blow molders of a blow molding cell dependent upon said characteristic of molten molding material.

14. The method of any one of claim 1 to claim 13 wherein said track comprises two carriages and further comprising:

bringing said two carriages together to trap said vessel between said carriages; and subsequently maintaining said two carriages together while moving said two carriages along said track in order to convey said vessel along said track.

15. The method of claim 14 further comprising gripping said vessel with grippers, thereafter separating said two carriages to release said vessel from said track, and thereafter manipulating said vessel with said grippers.

16. The method of claim 2 further comprising, upstream of said molten molding material dispensing cell, swapping said vessel for another vessel.

17. The method of any one of claim 1 to claim 16 wherein said vessel has a piston and

wherein said injecting comprises moving said piston.

18. A system for use in molding articles, comprising:

a track;

a plurality of vessels carried on said track;

at least one molten molding material dispenser along said track;

at least one molder along said track; and

a controller operatively associated with said track for selectively moving each vessel along said track (i) to a given dispenser of said at least one molten molding material dispenser whereat flowable molten molding material is dispensed to said each vessel and (ii) to a given molder of said at least one molder whereat molten molding material is dispensed from said each vessel.

19. The system of claim 18, comprising a position sensor interconnected with said controller for tracking a position of said each vessel.

20. The system of claim 18 or claim 19, wherein said at least one dispenser comprises a plurality of dispensers and said at least one molder comprises a plurality of molders, and wherein said controller is configured to select said given molder from said plurality of molders dependent upon a characteristic of molding material dispensed to said each vessel at said given dispenser.

21. The system of any one of claim 18 to claim 20 wherein said track has an outgoing line for carrying said vessels to said at least one molten molding material dispenser and to said at least one molder, and a return line for returning said vessels back toward said at least one molten molding material dispenser.

22. The system of claim 19 or claim 20 further comprising a transfer device for transferring articles molded at said given molder to said return line.

23. The system of claim 22 wherein said transfer device is a first transfer device and further comprising at least one blow molder along said return line and a second transfer device to transfer said articles on said return line to a given blow molder of said at least one blow molder.

24. The system of claim 22 or claim 23 wherein said return line is parallel to said outgoing line.

25. The system of any one of claim 18 to claim 24 wherein said track comprises a plurality of pairs of carriages, two carriages of each pair of carriages having complementary features for trapping said each vessel between said two carriages when said two carriages are brought together, said controller further operable to selectively bring said two carriages together and to move said two carriages while together in order to move said each vessel on said track.

26. The system of claim 22 or claim 23 wherein said track comprises a plurality of pairs of carriages, two carriages of each pair of carriages having complementary features for trapping at least one of said each vessel or an article of said articles between said two carriages when said two carriages are brought together, said controller further operable to selectively bring said two carriages together and to move said two carriages while together in order to move said each vessel or said article along said track.

27. The system of claim 25 further comprising a pair of spring loaded grippers mounted for reciprocal movement transversely of said track such that said grippers may be extended toward said track to deflect around and grip a given said each vessel trapped by said two carriages.

28. The system of any one of claim 18 to claim 27 wherein said each vessel has an identifier and further comprising a reader for reading said identifier of said each vessel, and wherein said controller is operatively associated with an output of said reader.

29. The system of claim 22 or claim 23 further comprising a shunt line mounted for

movement between a first position coupled to an end of said outgoing line and a second position coupled to an end of said return line in order to shunt said vessels from said outgoing line to said return line.

30. The system of claim 29 wherein said return line is parallel to said outgoing line and one of said outgoing line and said return line is directly above another of said outgoing line and said return line.

31. The system of claim 29 or claim 30 further comprising at least one vessel re-ordering device upstream of said at least one molten molding material dispenser, said at least one re-ordering device comprising a reciprocal turntable with a plurality of vessel grippers.

32. The system of claim 20 wherein said characteristic is a composition of said molding material.

33. The system of claim 32 wherein said composition is a thermoplastic or a thermoset plastic resin.

34. A plastic molding system comprising:

a feedstock cell comprising a feedstock station for depositing plastic feedstock into a vessel, deposited plastic feedstock defining a workpiece;

a pre-shaping cell comprising a plurality of pre-shaping stations each for shaping a given said workpiece into a preform shape by injection into a pre-shaping mold;

a shaping cell comprising a plurality of shaping stations each for shaping one said workpiece from said preform shape to a final shape in a mold;

a transport subsystem for advancing each said workpiece along a selected one of a plurality of process paths to form a molded article from said each said workpiece, wherein multiple ones of said process paths are defined by a combination of said feedstock station, a pre-shaping station of said pre-shaping cell and a shaping station of said shaping cell.

35. The plastic molding system of claim 34 wherein said feedstock cell is a dispensing cell and wherein said feedstock station is a dispensing station for dispensing a dose of plastic feedstock defining each said workpiece.

36. The plastic molding system of claim 35 wherein said dispensing cell

comprises a plurality of dispensing stations, and wherein each of said plurality of process paths includes one said dispensing station.

37. The plastic molding system of any one of claims 34 to 36 further comprising a thermal conditioning cell for producing a desired thermal profile in each said workpiece between said primary and secondary shaping cells.

38. The plastic molding system of any one of claims 34 to 37, wherein said plurality of process paths comprise a first process path for producing first molded articles having a first characteristic and a second process path for producing second molded articles having a second characteristic different from said first characteristic.

39. The plastic molding system of claim 38, wherein said characteristic comprises a shape.

40. The plastic molding system of any one of claims 34 to 39, wherein each said pre-shaping station comprises an injection molding apparatus and wherein each said shaping station comprises a blow molding apparatus.

41. The plastic molding system of claim 35 or 36, wherein each said dispensing station comprises an extruder for dispensing said plastic feedstock as molten plastic.

42. The plastic molding system of any one of claims 34 to 41, comprising a post-shaping cell for performing a finishing operation on said workpiece in said final shape.

43. The plastic molding system of claim 42, wherein said workpiece in said final shape is a bottle and said post-shaping cell comprises a filling station.

44. The plastic molding system of claim 42 or claim 43, wherein said post shaping cell comprises a labelling station.

45. The plastic molding system of any one of claims 42 to 44 wherein said post-shaping cell comprises a capping station.

46. A plastic molding system for a process comprising dispensing and shaping operations, the system comprising:

a dispensing cell comprising a dispensing mechanism for dispensing doses of a plastic feedstock into vessels to create workpieces;

a shaping cell comprising a plurality of shaping stations, each shaping station having a mold for receiving said plastic feedstock from a vessel and for forming said workpiece into a desired shape; and

a transport subsystem for advancing each said workpiece along a selected one of a plurality of possible process paths through each of said dispensing cell and said shaping cell, to form a molded article from said each said workpiece, wherein multiple ones of said possible process paths are defined by a combination of said dispensing mechanism and different ones of said plurality of shaping stations.

47. The plastic molding system of claim 46, comprising a conditioning cell comprising a plurality of conditioning stations, each for applying a treatment to one said workpiece prior to processing of said one said workpiece in said shaping cell, and wherein each of said possible process paths includes one of said conditioning stations.

48. The plastic molding system of claim 47, wherein said conditioning cell is configured under computer control to apply said treatment.

49. The plastic molding system of any one of claims 46 to 48, wherein said

dispensing cell comprises a plurality of dispensing mechanisms, and wherein each of said possible process paths includes one said dispensing mechanism.

50. The plastic molding system of any one of claims 46 to 48, wherein said dispensing cell is for dispensing individual doses of said plastic feedstock, each to form a single molded article.

51. The plastic molding system of any one of claims 46 to 50, wherein each of said

possible process paths includes a different combination of one said dispensing mechanism, and one said shaping station.

52. The plastic molding system of any one of claims 46 to 51, wherein said plurality of possible process paths comprise a first process path for producing first molded articles having a first characteristic and a second process path for producing molded articles having a second characteristic different from said first characteristic.

53. The plastic molding system of claim 52, wherein said characteristic comprises a shape.

54. The plastic molding system of any one of claims 46 to 53, wherein said shaping cell is a primary shaping cell and each shaping station is a primary shaping station for performing a primary shaping operation to form a pre-shaped article, and further comprising a secondary shaping cell for performing a secondary shaping operation to form each said molded article by re-shaping each said pre-shaped article.

55. The plastic molding system of claim 54, wherein each said primary shaping station comprises an injection molding apparatus and wherein said secondary shaping cell comprises a plurality of secondary shaping stations each comprising a blow molding apparatus.

56. The plastic molding system of any one of claims 46 to 55, wherein said dispensing cell comprises an extruder for dispensing said plastic feedstock as molten plastic.

57. The plastic molding system of any one of claims 46 to 56, wherein said transport subsystem comprises a guide mechanism and said plurality of process paths are at least partially defined by said guide mechanism.

58. The plastic molding system of claim 57 wherein said guide mechanism comprises a loop and a plurality of branches each connecting stations of said cells with said loop.

59. The plastic molding system of claim 57 or claim 58, wherein said guide mechanism comprises a track and a carriage mounted for movement on said track.

60. The plastic molding system of claim 59, wherein said guide mechanism comprises a plurality of carriages, and said transport subsystem comprises a plurality of diverting devices for selectively initiating directional change of said carriages to individual stations of said cells.

61. The plastic molding system of claim 54 or 55, wherein said primary shaping cell is for performing a primary shaping operation to form a pre-shaped article, and wherein said transport subsystem comprises a plurality of pre-shape carriages mounted for movement along said track, for receiving pre-shaped articles from said primary shaping cell and carrying the pre-shaped articles to a subsequent processing station.

62. The plastic molding system of any one of claims 46 to 61, comprising a post-shaping cell for performing a finishing operation on said workpiece in said final shape.

63. The plastic molding system of claim 62, wherein said workpiece in said final shape is a bottle and said post-shaping cell comprises a filling station.

64. The plastic molding system of claim 62 or claim 63, wherein said post-shaping cell comprises a labelling station.

65. The plastic molding system of any one of claim 62 to claim 64 wherein said post shaping cell comprises a capping station.

66. A method of molding plastic articles in a molding system comprising a plurality of feedstock providing stations and a plurality of shaping stations, the method comprising:

forming a first molded article by conveying a first quantity of feedstock through said molding system in a first process path, wherein said conveying comprises moving said first quantity in a vessel; and

forming a second molded article by conveying a second quantity of feedstock through said molding system in a second process path different from said first process path and partially overlapping with said first process path, wherein said conveying comprises moving said second quantity in a further vessel;

wherein each of said first process path and said second process path includes a feedstock providing station of said plurality of feedstock providing stations and a shaping station of said plurality of shaping stations.

67. The method of claim 66, wherein said molding system comprises at least one

conditioning station and each of said first process path and said second process path includes one said dose dispensing station, one said shaping station, and one said conditioning station.

68. The method of claim 67, wherein said shaping stations are primary shaping stations and each of said first process path and said second process path includes one said dispensing station, a primary shaping station, one said conditioning station and a secondary shaping station.

69. The method of claim 66 or claim 67, wherein said first process path includes a first shaping station and said second process path includes a second shaping station different from said first shaping station.

70. The method of any one of claims 66 to 69, wherein said conveying said first dose of feedstock comprises dispensing said first dose of feedstock into a first vessel and said conveying said second dose of feedstock comprises dispensing said second dose of feedstock into a second vessel.

71. The method of any one of claims 66 to 70, wherein said conveying said first dose of feedstock comprises dispensing said first dose from a first dispensing station and said conveying said second dose of feedstock comprises dispensing said second dose from a second dispensing station different from said first dispensing station.

72. The method of any one of claims 66 to 71, wherein said first molded article and said second molded article have different shapes.

73. The method of any one of claims 66 to 72, wherein said first molded article and said second molded article have different sizes.

74. The method of any one of claims 66 to 73, wherein said first molded article and said second molded article are formed of different materials.

75. The method of any one of claims 66 to 74, wherein each one of said first process path and said second process path includes an injection molding apparatus and a blow molding apparatus.

76. The method of any one of claims 66 to 75, wherein said conveying said first dose of feedstock and conveying said second dose of feedstock comprises conveying carriages along a track.

77. The method of claim 76, wherein said conveying said first dose of feedstock and conveying said second dose of feedstock comprises operating a diverting device to initiate a change in direction from a track loop towards individual ones of said shaping stations.

78. The method of any one of claims 66 to 77, wherein said molding system comprises a post-shaping station and said method further comprises performing a finishing operation in said post-shaping station.

79. The method of claim 78, wherein said finishing operation comprises filling.

80. The method of claim 78 or claim 79, wherein said finishing operation comprises labeling.

81. The method of any one of claim 78 to claim 80 wherein said finishing operation comprises capping.

82. A method for use in molding articles comprising:

dispensing a dose of molten plastic material into a vessel;

moving the vessel with the dose therein to a selected forming station of a plurality of available forming stations;

transferring the dose of molten material from the vessel to a forming apparatus at said selected forming station;

forming a molded article from said dose in said forming apparatus.

83. The method of claim 82 wherein said molded article is a pre-shaped molded article and further comprising moving said pre-shaped molded article to a finishing station of a plurality of available finishing stations and forming a finished molded article from said pre-shaped molded article at said finishing station.

84. A system for molding articles comprising:

means for dispensing a dose of molten plastic material into a vessel;

means for moving the vessel with the dose therein to a selected forming station of a plurality of available forming stations;

means for transferring the dose of molten material from the vessel to a forming apparatus at said selected forming station;

means for forming a molded article from said dose in said forming apparatus.

85. The system of claim 84 wherein said means for dispensing comprises a plurality of dispensers, each for dispensing a molten plastic material having a different composition.

86. 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 for selectively mating to a processing station to transfer molding material;

an ejection mechanism operable to force said molten molding material out of said vessel.

87. The apparatus of claim 86, wherein said ejection mechanism comprises a piston

received in the cavity.

88. The apparatus of claim 86 or claim 87, wherein said vessel comprises an orifice for receiving said molding material from a melter, and said coupling assembly comprises a seal assembly for selectively sealing said orifice.

89. The apparatus of claim 86, 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.

90. The apparatus of any one of claims 86 to 89, comprising a thermal regulating assembly on said container for controlling a thermal profile of said molten molding material.

91. The apparatus of claim 90, wherein said thermal regulating assembly comprises an insulator.

92. The apparatus of claim 90, wherein said thermal regulating assembly comprises a heat sink.

93. The apparatus of any one of claims 90 to 92, wherein said thermal regulating assembly comprises a sleeve around said vessel.

94. The apparatus of any one of claims 90 to 93, wherein said thermal regulating assembly includes a heating element.

95. The apparatus of any one of claims 84 to 94, wherein said coupling assembly is a seal assembly for selectively sealing said orifice.

96. The apparatus of claim 95, wherein said seal assembly includes a valve stem.

97. The apparatus of claim 96, wherein said valve stem extends along an axis of said vessel, within said internal cavity.

98. The apparatus of any one of claims 95 to 97, wherein said seal assembly comprises a sliding gate.

99. The apparatus of any one of claims 86 to 98, wherein said vessel is configured to

releasably engage with a transport device, for movement of said vessel relative to a processing station.

100. The apparatus of claim 99, wherein said vessel comprises a handling feature for

releasably securing said vessel to a transport device.

101. The apparatus of claim 100, wherein said transport device comprises a guide and said handling feature comprises an adapter configured to engage said vessel and said guide.

102. The apparatus of claim 101, wherein said seal assembly is part of said adapter.

103. A method of transporting molten molding material, comprising:

receiving molten molding material in an internal cavity of a vessel through an orifice; moving said vessel along a transport path;

preventing flow of said material during said moving;

mating said vessel with a mold;

transferring said molten molding material to said mold by forcing said molten molding material out of said vessel.

104. The method of claim 103, wherein said forcing the molten molding material out of the vessel comprises moving a piston in said internal cavity.

105. The method of claim 103 or claim 104, wherein said preventing flow comprises sealing said orifice.

106. The method of any one of claims 103 to 105, wherein said transferring comprises

forcing material out of said vessel through said orifice.

107. The method of any one of claims 103 to 106, comprising regulating heat transfer with said vessel.

108. The method of claim 107, wherein said regulating heat transfer comprises insulating said vessel to regulate heat loss.

109. The method of claim 107, wherein said regulating heat transfer comprises removing heat from said vessel with a heat sink.

110. The method of any one of claims 107 to 109, wherein said regulating heat transfer comprises introducing heat to said vessel with a heating element after said receiving.

111. The method of any one of claims 103 to 110, comprising releasably engaging said vessel with a transport device for said moving.

112. The method of claim 111, wherein said transport device comprises a guide and said releasably engaging comprises attaching said vessel to said guide with an adapter.

113. The method of claim 112, comprising sealing said orifice with said adapter.

114. An apparatus for transferring a flowable molding material between a container and a processing station, comprising:

a holder for supporting a container having an internal cavity for holding flowable molding material, said holder comprising a nest configured to matingly receive said container; a coupling device for selectively engaging said container with the processing station, to thereby establish a flow path for said flowable molding material between said container and said processing station;

a flow actuator for causing flow of said flowable molding material through said flow path.

115. The apparatus of claim 114, wherein said nest comprises an interlocking feature for maintaining a position of said container.

116. The apparatus of claim 114 or 115, wherein said apparatus comprises a locking actuator for biasing said container against said interlocking feature.

117. The apparatus of any one of claims 114 to 116, wherein said apparatus comprises a seal actuator for operating a seal of said container.

118. The apparatus of claim 117, wherein said seal actuator is in a nested relationship with one or more of said flow actuator and said locking actuator.

119. The apparatus of any one of claims 114 to 118, wherein said holder comprises a

triggering structure for releasing a seal of said container.

120. The apparatus of claim 119, 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.

121. The apparatus of any one of claims 114 to 120, wherein said processing station

comprises a dispensing station for transferring said flowable molding material to said container.

122. The apparatus of any one of claims 114 to 121, 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 said mold by displacement of a piston.