Injection nozzle and method for injection molding
AssigneeHusky Injection Molding Systems Ltd.
InventorsBruce Catoen, Rajan Puri
Life of this patent
Estimating the term…
Abstract
A valve stem is mounted in a nozzle body, with the valve stem moving from an open position retracted from the injection orifice permitting the flow of resin to the mold cavity, to a closed position blocking the injection orifice and preventing the flow of resin to the mold cavity, and to an advanced position within the gate nub area to assist in the ejection of a molded part and clear the gate nub area.
Claims76
An injection nozzle for injection molding resin from a source of molten resin to a mold cavity, which comprises:
- a mold cavity;
- an injection nozzle having a nozzle body and a nozzle tip and having an internal flow channel therein communicating with an injection orifice which in turn communicates with said mold cavity for transportation of molten resin to the mold cavity;
- a valve gate nub area between the mold cavity and injection orifice;
- a valve stem mounted in the injection nozzle;
- and
- means to move the valve stem between an open position retracted from the injection orifice permitting the flow of resin to the mold cavity, a fully closed position blocking the injection orifice and preventing flow of resin to the mold cavity, and an advanced position past the fully closed position and within the valve gate nub area to assist in ejection of a molded part and to clear the valve gate nub area.
A method for injection molding, which comprises:
- providing an injection nozzle having a nozzle body and a nozzle tip and having an internal flow channel therein communicating with an injection orifice which in turn communicates with a mold cavity;
- transporting molten resin from said internal flow channel to said mold cavity;
- positioning a valve gate nub area between the mold cavity and injection orifice;
- mounting the valve stem between an open position retracted from the injection orifice permitting the flow of resin to the mold cavity, a fully closed position blocking the injection orifice and preventing flow of resin to the mold cavity, and an advanced position past the fully closed position within the valve gate nub area to assist in ejection of a molded part and to clear the valve gate nub area.
A valve gate assembly for injection molding, in use, resin into a mold cavity, the valve gate assembly comprising:
- an injection nozzle having a nozzle body and a nozzle tip and having an internal flow channel therein communicating with an injection orifice which in turn communicates with said mold cavity for the transfer, in use, of resin to the mold cavity;
- a valve gate area between the mold cavity and injection orifice;
- a valve stem operatively positioned in the injection nozzle;
- and
- means to move the valve stem between (i) an open position retracted from the injection orifice permitting the flow of resin to the mold cavity, (ii) a fully closed position blocking the injection orifice and preventing flow of resin to the mold cavity, and (iii) an advanced position past the fully closed position and within the valve gate area to clear the valve gate area.
A valve gate assembly containing a nozzle body and a nozzle tip, the nozzle body having an internal channel terminating at the nozzle tip, the valve gate assembly further including a valve stem located within the internal channel and a valve stem actuator coupled to the valve stem to control a position of the valve stem relative to the nozzle tip, the valve gate assembly comprising:
- the valve stem actuator being configured to cause extension of the valve stem between (i) an open position, (ii) a fully closed position, and (ii) an advanced position beyond the fully closed position, the advanced position being sufficiently beyond the nozzle tip to cause the valve stem to clear away debris accumulated in front of the valve stem.
A method of operating a valve gate assembly associated with an injection mold, the valve gate assembly containing a nozzle body and a nozzle tip, the nozzle body having an internal channel terminating at the nozzle tip, the valve gate assembly further including a valve stem located within the internal channel and a valve stem actuator coupled to the valve stem to control a position of the valve stem relative to the nozzle tip, the method including the steps of:
- operating the valve stem actuator to move the valve from an open position to a fully closed position;
- and
- operating the valve stem actuator to move the valve stem beyond the fully closed position and beyond the nozzle tip such that the valve stem acts to clear away debris accumulated in front of the valve stem.
A method of clearing plastic debris from the vicinity of a gate orifice of a gate pad, the method comprising:
- moving the valve stem from an open position to a fully closed position;
- and
- forcing the valve stem beyond the fully closed position to extend through the gate orifice, to clear debris from the vicinity of the gate orifice.
An injection molding apparatus for injection molding from a source of molten material to a mold cavity, said nozzle comprising:
- a mold cavity;
- an injection nozzle having a nozzle body and a nozzle tip and having an internal flow channel therein communicating with an injection orifice which in turn communicates with said mold cavity for the transfer of molten material to the mold cavity;
- a valve gate area between the mold cavity and the injection orifice;
- a valve stem operatively positioned in the injection nozzle;
- and
- structure to move the valve stem between (i) an open position retracted from the injection orifice permitting the flow of material to the mold cavity, (ii) a fully closed position blocking the injection orifice and preventing flow of material to the mold cavity, and (iii) an advanced position past the fully closed position and within the valve gate area to clear the valve gate area.
An injection nozzle for injection molding from a source of molten material, said nozzle comprising:
- an elongated nozzle housing having an internal flow channel therein, said internal flow channel in communication with the source of molten material for communication of the molten material to a mold cavity;
- and
- a valve stem configured to (i) open the flow channel, (ii) fully close the flow channel, and (iii) move beyond the fully close position to clear said mold cavity of debris.
A method of clearing a gate orifice of an injection mold comprising the steps of:
- providing a valve stem movable between (i) a first position where molten material may flow through the gate orifice, (ii) a second position to fully stop the flow of molten material through the gate orifice, and (iii) a third position beyond the second position whereby said valve stem is placed completely through the gate orifice;
- and
- placing said valve stem through said gate orifice to remove debris therefrom.
An injection molding system for the formation of a molded article comprising:
- structure configured to provide a supply of molten material in communication with a melt channel in a manifold;
- a manifold plate having a cavity formed therein for the receipt of a nozzle housing;
- a central melt channel in said nozzle housing in fluid communication between said melt channel and a mold cavity;
- and
- a valve element configured to start and stop the flow of molten material to the mold cavity, said valve element being movable between an open position, a fully closed position, and a position beyond the fully closed position to clear debris from a gate area.
A method for injection molding, which comprises the steps of:
- providing an injection nozzle having a nozzle body and a nozzle tip, said nozzle having an internal flow channel therein communicating with an injection orifice which in turn communicates with a mold cavity;
- transporting molten material from said internal flow channel to said mold cavity;
- providing a valve gate area between the mold cavity and injection orifice;
- mounting the valve stem between (i) an open position retracted from the injection orifice permitting the flow of material to the mold cavity, (ii) a fully closed position blocking the injection orifice and preventing flow of resin to the mold cavity, and (iii) an advanced position past the fully closed position within the valve gate area to clear the valve gate area.
An injection nozzle for injection molding from a source of molten material, said nozzle comprising:
- a nozzle housing means having an internal flow channel therein, said internal flow channel in communication with the source of molten material for communication of the molten material to a mold cavity;
- a valve element means configured to move between an open position and a fully closed position to respectively start and stop the flow of the molten material to the mold cavity, said valve element means also being configured to move to a position beyond the fully closed position to clear at least a portion of said mold cavity of solidified material.
Dependencies are inferred from the claim text.