Shutheight adjuster for a sprue bar

A sprue bar assembly for use with an injection molding machine having at least one mold, said sprue bar assembly accommodating different mold shutheights and comprising:

• a fixed sprue bar section having a first channel through which molten material flows, said first channel communicating with a source of said molten material;
• means for accommodating molds having different shutheights;
• said accommodating means comprising at least one adjustable sprue bar section having a second channel through which molten material flows;
• said accommodating means further comprising powered means for moving said at least one adjustable sprue bar section relative to said fixed sprue bar section;
• and
• said powered means holding an end face of said at least one adjustable sprue bar section in contact with and against an opposed end face of said fixed sprue bar section so that molten material can flow from said first channel to said second channel without leaking.

A sprue bar assembly for use with an injection molding machine having at least one mold, said sprue bar assembly accommodating different mold shutheights and comprising:

• a fixed sprue bar section having a first channel through which molten material flows, said first channel communicating with a source of said molten material;
• means for accommodating different mold shutheights;
• said accommodating means comprising at least one adjustable sprue bar section having a second channel through which molten material flows;
• said accommodating means further comprising powered means for moving said at least one adjustable sprue bar section relative to said fixed sprue bar section;
• said powered means including a cylinder having a piston rod;
• and
• said piston rod being connected to said movable sleeve via a crosshead and at least one connecting rod.

A sprue bar assembly for use with an injection molding machine having at least one mold, said sprue bar assembly accommodating different mold shutheights and comprising:

• a fixed sprue bar section having a first channel through which molten material flows, said first channel communicating with a source of said molten material;
• means for accommodating different mold shutheights;
• said accommodating means comprising at least one adjustable sprue bar section having a second channel through which molten material flows;
• said accommodating means further comprising powered means for moving said at least one adjustable sprue bar section relative to said fixed sprue bar section;
• said source of molten material comprising a molten material injection unit;
• said fixed sprue bar section communicating with said injection unit via a sprue bush and a first fixed manifold, said sprue bush having a third channel communicating with an outlet nozzle of said injection unit and said first fixed manifold having a fourth channel in communication with said first and third channels;
• a sprue bar mounting section attached to a movable platen of said injection molding machine;
• and
• a fifth channel passing through said sprue bar mounting section, said fifth channel communicating with said second channel in said at least one adjustable sprue bar section and with a sixth channel within a manifold positioned within a manifold positioned within said movable platen.

A sprue bar assembly for use with an injection molding machine having at least one mold, said sprue bar assembly accommodating different mold shutheights and comprising:

• a fixed sprue bar section having a first channel through which molten material flows, said first channel communicating with a source of said molten material;
• means for accommodating different mold shutheights;
• said accommodating means comprising at least one adjustable sprue bar section having a second channel through which molten material flows;
• said accommodating means further comprising powered means for moving said at least one adjustable sprue bar section relative to said fixed sprue bar section;
• said powered means holding said at least one adjustable sprue bar section in contact with said fixed sprue bar section so that molten material can flow from said first channel to said second channel without leaking;
• said injection molding machine having a first mold formed by first and second mold halfs;
• said powered means comprising means for causing said at least one adjustable sprue bar section to maintain contact with said fixed sprue bar section when said first and second mold halfs are in contact with each other and when said first and second mold halfs are slightly separated;
• and
• said powered means further comprising means for causing said at least one adjustable sprue bar section to retract away from said fixed sprue bar section when said mold is fully opened.

A sprue bar assembly for use with an injection molding machine having at least one mold, said sprue bar assembly accommodating different mold shutheights and comprising:

• a fixed sprue bar section having a first channel through which molten material flows, said first channel communicating with a source of said molten material;
• means for accommodating different mold shutheights;
• said accommodating means comprising at least one adjustable sprue bar section having a second channel through which molten material flows;
• said accommodating means further comprising powered means for moving said at least one adjustable sprue bar section relative to said fixed sprue bar section;
• said powered means holding said at least one adjustable sprue bar section in contact with said fixed sprue bar section so that molten material can flow from said first channel to said second channel without leaking;
• a first valve gate in said fixed sprue bar section for positively closing said first channel when said fixed sprue bar section is not in contact with said at least one adjustable sprue bar section;
• and
• a second valve gate in said at least one adjustable sprue bar section for positively closing said second channel when said at least one adjustable sprue bar section is not in contact with said fixed sprue bar section.

A sprue bar assembly for use with an injection molding machine having at least one mold, said sprue bar assembly accommodating different mold shutheights and comprising:

• a fixed sprue bar section having a first channel through which molten material flows, said first channel communicating with a source of said molten material;
• means for accommodating different mold shutheights;
• said accommodating means comprising at least one adjustable sprue bar section having a second channel through which molten material flows;
• said accommodating means further comprising powered means for moving said at least one adjustable sprue bar section relative to said fixed sprue bar section;
• said fixed sprue bar section comprising a fixed manifold section;
• said accommodating means comprising a first adjustable sprue bar section movable relative to said fixed manifold section and a second adjustable sprue bar section movable relative to said first adjustable sprue bar section.

A sprue bar assembly for use with an injection molding machine having at least one mold, said sprue bar assembly accommodating different mold shutheights and comprising:

• a fixed sprue bar section having a first channel through which molten material flows, said first channel communicating with a source of said molten material;
• means for accommodating different mold shutheights;
• said accommodating means comprising at least one adjustable sprue bar section having a second channel through which molten material flows;
• said accommodating means further comprising powered means for moving said at least one adjustable sprue bar section relative to said fixed sprue bar section;
• said fixed sprue bar section comprising a fixed manifold section;
• said accommodating means comprising a first adjustable sprue bar section movable relative to said fixed manifold section and a second adjustable sprue bar section movable relative to said first adjustable sprue bar section;
• and
• said first and second adjustable sprue bar sections being movable between positions where they contact each other and positions where they are separated.

A molding machine for making molded parts, said machine comprising:

• a stationary platen having a first mold half affixed thereto;
• a center platen movable relative to said stationary platen;
• said center platen having a second mold half affixed to a first surface and a third mold half affixed to a second surface;
• a movable platen which moves relative to said center platen and said stationary platen;
• said movable platen having a fourth mold half affixed thereto;
• said first and second mold halfs forming a first mold and said third and fourth mold halfs forming a second mold;
• an injection unit for providing molten material to said first and second molds;
• a manifold in said center platen for distributing said molten material to said first and second molds when
• said first and second molds are in a mold closed position;
• a sprue bar assembly connecting an outlet of said injection unit to said manifold;
• said sprue bar assembly having means for accommodating different shutheights of said first and second molds;
• and
• said accommodating means comprising powered means for adjusting the length of the sprue bar assembly.

A molding machine comprising:

• a mold formed by first and second mold halfs;
• a sprue bar assembly for feeding a metered amount of molten material into the mold;
• and
• said sprue bar assembly including means for reducing the length of said sprue bar assembly as said mold is moved from a partially open position to a fully closed position.

A molding machine comprising:

• a mold formed by first and second mold halfs;
• a sprue bar assembly for feeding a metered amount of molten material into the mold;
• said sprue bar assembly including means for adjusting the length of said sprue bar assembly when said mold is moved to a fully closed position;
• and
• said sprue bar assembly including a fixed sprue bar section and an adjustable sprue bar section which mates with said fixed sprue bar section when said mold is partially closed and wherein said adjusting means comprises a movable sleeve connected to said adjustable sprue bar section and a power unit joined to said movable sleeve.

A molding machine comprising:

• a mold formed by first and second mold halfs;
• a sprue bar assembly for feeding a metered amount of molten material into the mold;
• said sprue bar assembly including means for adjusting the length of said sprue bar assembly when said mold is moved to a fully closed position;
• said sprue bar assembly including a fixed sprue bar section and an adjustable sprue bar section which mates with said fixed sprue bar section when said mold is partially closed and said adjusting means comprises a movable sleeve connected to said adjustable sprue bar section and a power unit joined to said movable sleeve;
• said power unit moving said movable sleeve and said adjustable sprue bar section so as to cause said length of said sprue bar assembly to decrease as said mold moves from a partially closed position to said fully closed position;
• said power unit moving said movable sleeve so as to maintain contact between said adjustable sprue bar section and said fixed sprue bar section as said mold moves from said fully closed position to a partially open position;
• said power unit moving said movable sleeve so as to break contact between said adjustable sprue bar section and said fixed sprue bar section as said mold moves from said partially open position to a full open position;
• and
• each of said adjustable sprue bar section and said fixed sprue bar section being provided with a valve gate to prevent leakage of molten material.

A molding machine comprising:

• a mold formed by first and second mold halfs;
• a sprue bar assembly for feeding a metered amount of molten material into the mold;
• said sprue bar assembly including means for adjusting the length of said sprue bar assembly when said mold is moved to a fully closed position;
• and
• said sprue bar assembly for feeding a metered amount of molten material into said mold feeding said molten material into said mold while said mold is in a closed but unclamped condition and said sprue bar assembly adjusting in length as said mold opens as said metered amount of molten material is injected therein and then moves toward a fully closed position so as to compress the molten material.

A molding machine comprising:

• a mold formed by first and second mold halfs;
• a sprue bar assembly for feeding a metered amount of material into the mold;
• said sprue bar assembly including means for adjusting the length of said sprue bar assembly when said mold is moved to a fully closed position;
• and
• said sprue bar assembly for feeding a metered amount of molten material into said mold feeding said molten material into said mold while said mold is partially closed and said sprue bar assembly adjusting in length as said mold moves from said partially closed position to said fully closed position.

A molding machine comprising:

• a stationary platen having a first mold half affixed thereto;
• a moving platen having a second mold half affixed thereto;
• said first and second mold halfs when in a closed position forming a mold for producing a molded article;
• means for injecting multiple plastic materials into said mold;
• said injecting means including a hot runner manifold mounted to said moving platen for supplying one of said plastic materials to said mold, a source of said one plastic material, and an adjustable length sprue bar assembly joining said manifold and said source for transmitting said one plastic material from said source to said manifold;
• and
• said adjustable length sprue bar assembly including a fixed sprue bar section and a movable sprue bar assembly which can be moved from a first position abutting said fixed sprue bar section to a second position spaced from said fixed sprue bar section;
• and
• said movable sprue bar assembly being movable independently of said moving platen.

A molding machine comprising:

• a stationary platen having a first mold half affixed thereto;
• a moving platen having a second mold half affixed thereto;
• said first and second mold halfs when in a closed position forming a mold for producing a molded article;
• means for injecting multiple plastic materials into said mold;
• said injecting means including a hot runner manifold mounted to said moving platen for supplying one of said plastic materials to said mold, a source of said one plastic material, and an adjustable length sprue bar assembly joining said manifold and said source for transmitting said one plastic material from said source to said manifold;
• said adjustable length sprue bar assembly including powered means to adjust the length of said sprue bar assembly;
• said adjustable length sprue bar assembly including an adjustable sprue bar section which extends or retracts relative to said manifold and said powered means comprising a power unit connected to said adjustable sprue bar section via an adjustable sleeve;
• and
• said power unit comprising a fluid actuated piston cylinder unit and said piston cylinder unit being connected to said adjustable sleeve via a crosshead and at least one connecting rod.

A process for making a molded article, said process comprising:

• providing a mold formed by first and second mold halfs and a sprue bar assembly for receiving molten material from a molten material source;
• feeding a metered amount of molten material into the mold while said mold is partially closed;
• and
• adjusting the length of said sprue bar assembly as said mold is moved to a fully closed position.

A process for making a molded article, said process comprising:

• providing a mold formed by first and second mold halfs and a sprue bar assembly for receiving molten material from a molten material source;
• feeding a metered amount of molten material into the mold while said mold is in a closed but unclamped condition;
• and
• adjusting the length of said sprue bar assembly as said mold opens as said metered amount of molten material is injected into said mold and as said mold then moves toward a fully closed position so as to compress the molten material.

A molding machine comprising:

• two platens each having a mold half affixed thereto for forming a mold, at least one of said platens moving relative to the other of said platens;
• said at least one moving platen having a manifold;
• a source of molten material;
• a sprue bar assembly communicating with said source of molten material and said manifold;
• said sprue bar assembly including a fixed sprue bar section and an adjustable sprue bar section;
• powered means for moving said adjustable sprue bar section relative to said manifold between a first position where said adjustable sprue bar section contacts said fixed sprue bar section and a second position where said adjustable sprue bar section does not contact said fixed sprue bar section;
• and
• a control unit for operating said adjustable sprue bar section.

A sprue bar assembly for use with an injection molding machine having at least one mold, said sprue bar assembly accommodating different mold shutheights and comprising:

• a first adjustable sprue bar section having a first channel through which molten material flows, said first channel communicating with a source of said molten material;
• a second adjustable sprue bar section having a second channel through which molten material flows;
• said first and second adjustable sprue bar sections allowing said assembly to accommodate said different mold shutheights;
• and
• powered means for holding said first and second adjustable sprue bar sections in contact with each other so that molten material can flow from said first channel to said second channel without leaking and for moving at least one of said first and second adjustable sprue bar sections to a retracted position where said first and second adjustable sprue bar sections are not in contact with each other.

A sprue bar assembly for use with an injection molding machine having at least one mold, said sprue bar assembly accommodating different mold shutheights and comprising:

• a first adjustable spire bar section having a first channel through which molten material flows, said first channel communicating with a source of said molten material;
• a second adjustable sprue bar section having a second channel through which molten material flows;
• said first and second adjustable sprue bar sections allowing said assembly to accommodate said different mold shutheights;
• powered means for holding said first and second adjustable sprue bar sections in contact with each other so that molten material can flow from said first channel to said second channel without leaking;
• a fixed manifold section;
• and
• a first movable sleeve mounted within said fixed manifold section, said first movable sleeve joined to said first adjustable sprue bar section for extending and retracting said first adjustable sprue bar section relative to said fixed manifold section, thereby changing the length of the sprue bar assembly.

A mechanism for sealing two adjacent material transporting passageways comprising:

• a first gate valve assembly located in a first passageway;
• said second valve gate assembly located in a second passageway;
• each valve gate assembly having a valve stem movable between an open and a closed position;
• each valve stem having a tip portion, at least one external peripheral groove surrounding the periphery of said valve stem, and a channel at said tip portion communicating with said at least one external peripheral groove;
• and
• said channel in each said valve stem tip portion removing any material trapped between said valve stems as said valve stems move to their closed positions.

A valve gate assembly for closing off a material transporting passageway comprising:

• a valve stem movable between an open position and a closed position;
• said valve stem having a longitudinal axis, a tip portion, a channel within said tip portion, and at least one external vent groove surrounding the periphery of said valve stem;
• and
• said channel communicating with said at least one external vent groove and having a first portion extending coaxially with said longitudinal axis and a second portion angled with respect to said longitudinal axis.