Injection molding apparatus having an edge-gated runnerless nozzle

1. A runnerless nozzle comprising:

a nozzle body defining an upstream channel;

a downstream bracing component having an internal space and a lateral bore extending outwardly from the internal space through the bracing component;

a nozzle tip and a sealing component installable through the internal space and extending outwardly through the lateral bore, the sealing component having a sealing surface for engaging a gate component that defines a mold gate;

a securing component separate from the nozzle body and disposed in the internal space to hold the nozzle tip and the sealing component against the bracing component;

wherein at least one of the bracing component and the securing component defines a lateral channel in communication with the upstream channel for delivering molding material to the nozzle tip.

2. The runnerless nozzle according to claim 1 , wherein the sealing surface of the sealing component is circumferential for mating with a bore in the gate component.

3. The runnerless nozzle according to claim 1 , wherein the nozzle tip and the sealing component are separate pieces.

4. The runnerless nozzle according to claim 1 , wherein the bracing component includes a plurality of lateral bores radially spaced evenly around the bracing component, and wherein the nozzle tip and sealing component comprise a plurality of nozzle tips and sealing components, each of the nozzle tips and sealing components installable through the internal space and extending outwardly through a corresponding one of the lateral bores.

5. The runnerless nozzle according to claim 1 , wherein the nozzle tip and the sealing component each has a shoulder and the nozzle tip shoulder presses the sealing component shoulder against the bracing component when the securing component is disposed in the internal space of the bracing component.

6. The runnerless nozzle according to claim 5 wherein the nozzle tip shoulder and the sealing component shoulder are stepped shoulders.

7. The runnerless nozzle according to claim 5 , wherein the nozzle tip shoulder and the sealing component shoulder are tapered shoulders.

8. The runnerless nozzle according to claim 1 , wherein the securing component has an outside surface which contacts an upstream surface of the nozzle tip to engage a downstream shoulder of the nozzle tip with a shoulder of the bracing component when the securing component is disposed in the internal space.

9. The runnerless nozzle according to claim 8 , wherein the outside surface of the securing component and the upstream surface of the nozzle tip are angled.

10. The runnerless nozzle according to claim 1 , wherein at least one of the bracing component and securing component is slidably coupled to the nozzle body.

11. The runnerless nozzle according to claim 1 , further comprising a locator for locating the securing component with respect to a mold plate.

12. The runnerless nozzle according to claim 11 , wherein the locator is a point of support for the securing component.

13. A runnerless nozzle comprising:

a nozzle body defining an upstream channel;

a downstream bracing component having an internal space and a lateral bore extending outwardly from the internal space through the bracing component;

a nozzle tip and a sealing component extending outwardly through the lateral bore from the internal space, the sealing component having a sealing surface for engaging a gate component that defines a mold gate; and

a securing component separate from the nozzle body and disposed in the internal space to hold the nozzle tip and the sealing component against the bracing component;

wherein at least one of the bracing component and the securing component defines a lateral channel in communication with the upstream channel for delivering molding material to the nozzle tip.

14. The runnerless nozzle according to claim 13 , wherein the sealing surface of the sealing component is circumferential for mating with a bore in gate component.

15. The runnerless nozzle according to claim 13 , wherein the nozzle tip and the sealing component are separate pieces.

16. The runnerless nozzle according to claim 13 , wherein the bracing component includes a plurality of lateral bores radially spaced evenly around the bracing component, and wherein the nozzle tip and sealing component comprise a plurality of nozzle tips and sealing components, each of the nozzle tips and sealing components installable through the internal space and extending outwardly through a corresponding one of the lateral bores.

17. The runnerless nozzle according to claim 13 , wherein the nozzle tip and the sealing component each has a shoulder and the nozzle tip shoulder presses the sealing component shoulder against the bracing component when the securing component is disposed in the internal space of the bracing component.

18. The runnerless nozzle according to claim 17 , wherein the nozzle tip shoulder and the sealing component shoulder are stepped shoulders.

19. The runnerless nozzle according to claim 17 , wherein the nozzle tip shoulder and the sealing component shoulder are tapered shoulders.

20. The runnerless nozzle according to claim 13 , wherein the securing component has an outside surface which contacts an upstream surface of the nozzle tip to engage a downstream shoulder of the nozzle tip with a shoulder of the bracing component when the securing component is disposed in the internal space.

21. The runnerless nozzle according to claim 20 , wherein the outside surface of the securing component and the upstream surface of the nozzle tip are angled.

22. The runnerless nozzle according to claim 13 , wherein at least one of the bracing component and securing component is slidably coupled to the nozzle body.

23. The runnerless nozzle according to claim 13 , further comprising a locator for locating the securing component with respect to a mold plate.

24. The runnerless nozzle according to claim 23 , wherein the locator is a point of support for the securing component.