초록 ▼

Method for sealing interfaces within an injection mold having a first surface and a second surface includes structure and/or steps whereby an active material actuator configured to be disposed in a manner suitable for generating a force between the first surface and the second surface. The active ma

Method for sealing interfaces within an injection mold having a first surface and a second surface includes structure and/or steps whereby an active material actuator configured to be disposed in a manner suitable for generating a force between the first surface and the second surface. The active material actuator is configured to generate a force in response to sense signals from a transmission structure. Methods are also provided for centering a nozzle tip within a gate opening, and adjusting tip height of a nozzle tip with respect to a gate opening, also using active material inserts.

대표청구항 ▼

What is claimed is: 1. A method of sealing a nozzle body against a manifold of an injection mold, comprising: energizing an active material element actuator so as to generate a sealing force between said nozzle body and said manifold sensing pressure between said nozzle body and said manifold; and

What is claimed is: 1. A method of sealing a nozzle body against a manifold of an injection mold, comprising: energizing an active material element actuator so as to generate a sealing force between said nozzle body and said manifold sensing pressure between said nozzle body and said manifold; and controlling the energizing of said active material element actuator in a closed loop feedback system, based on sensed pressure between the nozzle body and manifold. 2. A method for sealing (i) a first surface comprising an injection molding nozzle head and (ii) a second surface comprising a hot runner manifold, in an injection mold, comprising the steps of: disposing an active material actuator to move the first surface toward the second surface; and actuating said active material actuator to cause said active material actuator to seal the injection molding nozzle head to the hot runner manifold, wherein said active material actuator comprises a tubular piezo-electric actuator configured to expand axially upon the application of an electrical voltage. 3. A method for sealing (i) a first surface comprising an injection molding nozzle head and (ii) a second surface comprising a hot runner manifold, in an injection mold, comprising the steps of: disposing an active material actuator to move the first surface toward the second surface; actuating said active material actuator to cause said active material actuator to seal the injection molding nozzle head to the hot runner manifold; disposing an active material sensor to detect pressure between the first surface and the second surface and provide a sense signal corresponding thereto; and providing to said active material actuator an actuation signal which corresponds to the pressure detected by said sensor. 4. A method according to claim 2, further comprising the steps of: disposing an insulator between the first surface and the second surface; and disposing said active material actuator between the insulator and the first surface. 5. A method for moving the nozzle tip of an injection mold hot runner nozzle with respect to a mold gate, comprising: disposing an active material actuator to move the nozzle tip with respect to the mold gate, wherein said active material actuator comprises a tubular piezo-electric actuator configured to expand axially upon the application of an electrical voltage; and supplying an actuation signal to said active material actuator to cause said active material actuator to change at least one dimension to effect relative movement between the nozzle tip and the mold gate. 6. A method according to claim 5, further comprising the step of disposing biasing structure to bias the nozzle toward the mold gate, and wherein said active material actuator is disposed to move the nozzle against the biasing structure. 7. A method according to claim 5, further comprising: using a sensor for detecting at least one of (i) a distance between the nozzle and the mold gate, and (ii) a pressure between the nozzle and the mold gate, and to output a sense signal corresponding thereto; and provide the actuation signal to cause the active material actuator to adaptively adjust the distance between the nozzle and the mold gate in accordance with the sense signal. 8. A method according to claim 7, wherein said sensor and said actuator each comprises piezoceramic element. 9. A method according to claim 5, wherein the nozzle has a nozzle head disposed adjacent a hot runner manifold, and further comprising the step of disposing a second active material actuator configured to (i) change at least one dimension upon receipt of an electrical voltage and (ii) effect a seal between the nozzle head and the hot runner manifold. 10. A sealing method in an injection mold having a manifold plate and a nozzle, comprising: disposing a piezo-electric sensor adjacent at least one of the nozzle and the manifold plate; sensing with the sensor a compressive force applied between the nozzle and the manifold plate, and generating a corresponding sense signal; disposing a piezo-electric actuator between the nozzle and the manifold plate; changing a dimension of said piezo-electric actuator upon application of the sense signal from said sensor to change a sealing force between the nozzle and the manifold plate. 11. A method according to claim 10, wherein said piezo-electric sensor is configured to be disposed in an annular groove in at least one of the nozzle and the manifold plate. 12. A method according to claim 10, further comprising the step of disposing a plurality of piezo-electric sensors at different locations between the nozzle and the manifold plate. 13. A method according to claim 10, further comprising the step of deposing a processor to receive the sense signal from said piezo-electric sensor and to generate one or more of corresponding (i) a clamping force signal, (ii) an injection pressure signal, and (iii) an injection rate signal. 14. A method according to claim 10, further comprising the step of deposing a second piezo-electric actuator between a manifold and the manifold plate to apply a sealing force between the manifold and the manifold plate. 15. A method according to claim 10, wherein said piezo-electric actuator is disposed adjacent said piezo-electric sensor, and wherein said piezo-electric sensor senses a change in dimension of said piezo-electric actuator corresponding to a change in distance between the nozzle and the manifold plate. 16. A method according to claim 10, further comprising the step of disposing a plurality of piezo-electric actuators at different locations between the nozzle and the manifold plate. 17. A method according to claim 16, wherein said plurality of piezo-electric actuators are disposed to control a deflection of the manifold plate. 18. A method according to claim 10, further comprising the step of disposing a plurality of piezo-electric sensors at different locations between the nozzle and the manifold plate, and wherein the injection molding machine includes a plurality of nozzles, and wherein at least one piezo-electric sensor and at least one piezo-electric actuator is disposed adjacent each nozzle. 19. A method according to claim 18, further comprising the step of providing a control structure configured to (i) receive sense signals from said plurality of piezo-electric sensors, and (ii) transmit actuator signals to said plurality of piezo-electric actuators to control a deflection of the manifold plate. 20. A method for sealing a nozzle head against an injection mold manifold, comprising: disposing a nozzle body with a nozzle tip insert; disposing a nozzle insulator around said nozzle body; disposing a tip insulator in said nozzle tip; disposing a manifold; disposing a manifold plate; disposing a mold cavity insert; disposing a piezoelectric actuator between at least two of: said nozzle body, said nozzle tip insert, said nozzle insulator, said tip insulator, said manifold, and said manifold plate; and providing an electrical signal to piezoelectric actuator to provide a sealing force between the nozzle head and the injection mold manifold. 21. A method for sealing a hot runner assembly, comprising: disposing a sprue bushing; disposing a manifold; disposing a nozzle body comprising a nozzle housing and a nozzle tip; sealing interfaces between the sprue bushing and the manifold and between the manifold and the nozzle, by changing a dimension of active material elements; sensing pressure between said nozzle body and said manifold; and controlling the energizing of at least one of said active material elements in a closed loop feedback system, based on sensed pressure between the nozzle body and manifold. 22. A method for controlling the position of a melt channel plug with respect to the melt channel in a molding machine, comprising: disposing the melt channel plug adjacent the melt channel; disposing a set screw adjacent the melt plug; disposing an active material element between the melt channel plug and the set screw; and providing an electrical signal to the active material element to control the position of the melt channel plug with respect to the melt channel. 23. A method for maintaining a seal around a melt channel plug provided in a melt channel of an injection molding manifold, comprising: sensing pressure between said melt channel plug and said melt channel; and regulating sealing forces applied by said melt channel plug on said melt channel by actuating a piezoelectric motor using a closed loop feedback system, based on the sensed pressure between said melt channel plug and said melt channel.