Edge Gated Injection Molding Apparatus

• US 20080152752A1
• Filed: 12/21/2007
• Published: 06/26/2008
• Est. Priority Date: 12/22/2006
• Status: Active Grant

• Current Assignee: Mold-Masters Limited
• Original Assignee: Mold-Masters Limited
• Inventors: Babin, Denis, Klobucar, Peter
• Granted Patent: US 7,658,606 B2
• Time in Patent Office: Days
• US Class Current: 425/549
• CPC Class Codes: B29C 2045/2813 Common drive means for several needle valves
• CPC Class Codes: B29C 2045/2831 Needle valves driven by a cam
• CPC Class Codes: B29C 45/2735 for non-coaxial gates, e.g. for edge gates
• CPC Class Codes: B29C 45/281 Drive means therefor

Abstract

An injection molding apparatus includes an injection manifold having an inlet and a melt channel. The manifold melt channel branches to a plurality of melt channel outlets. A hot runner injection nozzle includes an axial melt channel extending along a central axis and communicating with one of the manifold melt channel outlets. The nozzle further includes at least two angled melt channels disposed at an angle to the central axis. At least two nozzle tips are provided, and each includes a nozzle tip melt channel in communication with one of the angled melt channels. A valve pin is disposed at least partially within the axial melt channel coaxially with the central axis and movable within the axial melt channel. Lateral valve pins movable within the nozzle tip melt channels are disposed at an angle to the valve pin. Linkage elements continuously connect the lateral valve pins to the valve pin. Axial movement of the valve pin is transmitted through the linkage elements to the lateral valve pins to open and close communication between the nozzle tip melt channels and the lateral mold gates.

Claims

1. An injection molding apparatus comprising:

an injection manifold having an inlet and a melt channel, wherein said melt channel branches to a plurality of melt channel outlets;

a hot runner injection nozzle having an axial melt channel extending along a central axis and communicating with one of the melt channel outlets, the hot runner injection nozzle also including at least two angled melt channels disposed at an angle with respect to the central axis such that the angled melt channels and the axial melt channel are not parallel to each other;

at least two nozzle tips each including a nozzle tip melt channel, wherein the nozzle tip melt channel is in communication with one of the angled melt channels;

a primary valve pin disposed at least partially within the axial melt channel coaxially with the central axis and movable within the axial melt channel;

at least two secondary valve pins movable inside the nozzle tip melt channels, wherein the secondary valve pins are disposed at an angle with respect to the primary valve pin such that the secondary valve pins are not parallel to the primary valve pin;

a linkage element connecting the secondary valve pins to the primary valve pin; and

at least two lateral mold gates disposed at an angle with respect to the central axis such that the mold gates are not parallel to the central axis, each mold gate communicating with a mold cavity, wherein the axial movement of the primary valve pin is transmitted through the linkage element to the secondary valve pins to open and close communication between the nozzle tip melt channels and the lateral mold gates.

2. The injection molding apparatus of claim 1, wherein the hot runner injection nozzle includes a first nozzle portion including the axial melt channel and a second nozzle portion including the angled melt channels.

3. The injection molding apparatus of claim 2, wherein the first nozzle portion and the second nozzle portion are separate pieces.

4. The injection molding apparatus of claim 3, further comprising a nozzle link connecting the first nozzle portion to the second nozzle portion.

5. The injection molding apparatus of claim 1, further comprising a heater surrounding the axial melt channel.

6. The injection molding apparatus of claim 5, wherein the heater also surrounds the angled melt channels.

7. The injection molding apparatus of claim 5, further comprising a second independent heater surrounding the angled melt channels.

8. The injection molding apparatus of claim 1, wherein said linkage element includes a slider coupled to each of the secondary valve pins.

9. The injection molding apparatus of claim 8, wherein the sliders of the linkage element are each coupled to a Y-shaped element and the Y-shaped element is coupled to the primary valve pin.

10. The injection molding apparatus of claim 9, wherein in the Y-shaped element includes at least two arms and a head portion, wherein each arm is disposed in an angled slot in one of the sliders and the head portion is coupled to the primary valve pin.

11. The injection molding apparatus of claim 1, wherein said linkage element is a truncated pyramid shape and includes a notched slot in side surfaces thereof, wherein each notice slot receives a head of a respective secondary valve pin.

12. The injection molding apparatus of claim 11, wherein said at least two secondary valve pins comprise four secondary valve pins, and said at least two lateral mold gates comprise four lateral mold gates.

13. An injection molding apparatus comprising:

an injection manifold having an inlet and a melt channel;

a hot runner injection nozzle including a first nozzle portion, a separate second nozzle portion, and a nozzle link coupling the first nozzle portion to the second nozzle portion, wherein said first nozzle portion includes an axial melt channel extending along a central axis and communicating with said manifold melt channel, wherein the nozzle link includes a nozzle link melt channel communicating with said axial melt channel, and wherein said second nozzle portion includes at least two angled melt channels disposed at an angle with respect to the central axis such that the angled melt channels and the axial melt channel are not parallel to each other;

at least two nozzle tips each including a nozzle tip melt channel, wherein the nozzle tip melt channel is in communication with one of the angled melt channels;

a primary valve pin generally parallel to the central axis;

at least two secondary valve pins movable inside the nozzle tip melt channels, wherein the secondary valve pins are disposed at an angle with respect to the primary valve pin such that the secondary valve pins are not parallel to the primary valve pin;

a linkage element connecting the secondary valve pins to the primary valve pin; and

at least two lateral mold gates disposed at an angle with respect to the central axis such that the mold gates are not parallel to the central axis, each mold gate communicating with a mold cavity, wherein axial movement of the primary valve pin is transmitted through the linkage element to the secondary valve pins to open and close communication between the nozzle tip melt channels and the lateral mold gates.

14. The injection molding apparatus of claim 13, further comprising a heater surrounding the axial melt channel.

15. The injection molding apparatus of claim 14, wherein the heater also surrounds the angled melt channels.

16. The injection molding apparatus of claim 13, further comprising a second independent heater surrounding the angled melt channels.

17. The injection molding apparatus of claim 13, wherein said linkage element includes a slider coupled to each of the secondary valve pins.

18. The injection molding apparatus of claim 17, wherein the sliders of the linkage element are each coupled to a Y-shaped element and the Y-shaped element is coupled to the primary valve pin.

19. The injection molding apparatus of claim 18, wherein in the Y-shaped element includes at least two arms and a head portion, wherein each arm is disposed in an angled slot in one of the sliders and the head portion is coupled to the primary valve pin.

20. The injection molding apparatus of claim 13, wherein said linkage element is a truncated pyramid shape and includes a notched slot in side surfaces thereof, wherein each notice slot receives a head of a respective secondary valve pin.

21. The injection molding apparatus of claim 20, wherein said at least two secondary valve pins comprise four secondary valve pins, and said at least two lateral mold gates comprise four lateral mold gates.

22. The injection molding apparatus of claim 13, wherein said primary valve pin is disposed at least partially within the axial melt channel coaxially with the central axis and is movable within the axial melt channel.

23. An injection molding apparatus comprising:

an injection manifold having an inlet and a melt channel, wherein said melt channel branches to a plurality of melt channel outlets;

a hot runner injection nozzle having an axial melt channel extending along a central axis and communicating with one of the melt channel outlets, the hot runner injection nozzle also including at least two angled melt channels disposed at an angle with respect to the central axis such that the angled melt channels and the axial melt channel are not parallel to each other;

at least two nozzle tips each including a nozzle tip melt channel, wherein the nozzle tip melt channel is in communication with one of the angled melt channels;

a primary valve pin disposed parallel to the central axis;

at least two secondary valve pins movable inside the nozzle tip melt channels, wherein the secondary valve pins are disposed at an angle with respect to the primary valve pin such that the secondary valve pins are not parallel to the primary valve pin;

at least two sliders, each slider being coupled to a respective one of the secondary valve pins such that said slider move generally parallel to said secondary valve pins;

a linkage element coupling the sliders to the primary valve pin; and

at least two lateral mold gates disposed at an angle with respect to the central axis such that the mold gates are not parallel to the central axis, each mold gate communicating with a mold cavity, wherein the axial movement of the primary valve pin is transmitted through the linkage element and the sliders to the secondary valve pins to open and close communication between the nozzle tip melt channels and the lateral mold gates.

24. The injection molding apparatus of claim 23, wherein the linkage element is Y-shaped.

25. The injection molding apparatus of claim 24, wherein in the Y-shaped element includes at least two arms and a head portion, wherein each arm is disposed in an angled slot in one of the sliders and the head portion is coupled to the primary valve pin.

26. The injection molding apparatus of claim 23, wherein the hot runner injection nozzle includes a first nozzle portion including the axial melt channel and a second nozzle portion including the angled melt channels.

27. The injection molding apparatus of claim 26, wherein the first nozzle portion and the second nozzle portion are separate pieces.

28. The injection molding apparatus of claim 27, further comprising a nozzle link connecting the first nozzle portion to the second nozzle portion.

29. The injection molding apparatus of claim 23, further comprising a heater surrounding the axial melt channel.

30. The injection molding apparatus of claim 29, wherein the heater also surrounds the angled melt channels.

31. The injection molding apparatus of claim 29, further comprising a second independent heater surrounding the angled melt channels.

32. The injection molding apparatus of claim 23, wherein said primary valve pin is disposed at least partially within the axial melt channel coaxially with the central axis and is movable within the axial melt channel.