Variable-area fuel injector with improved circumferential spray uniformity

Patent metadata

Field	Value
Publication number	US-9683739-B2
Application number	US-61507309-A
Country	US
Kind code	B2
Filing date	Nov 9, 2009
Priority date	Nov 9, 2009
Publication date	Jun 20, 2017
Grant date	Jun 20, 2017

Abstract

A fuel injector having a body with a bore, which defines a fuel manifold. The injector also has a variable-area injector arrangement having a pintle with a conical head and a pintle spring connected to the body. The pintle spring urges a tip of the pintle to seal against an exit orifice of the body, such that application of pressurized fuel within the body causes the pintle to move. Above some threshold pressure, the pressurized fuel causes the conical head to move out of contact with the exit orifice of the body. This, in turn, provides a corresponding variable area for passage of the pressurized fuel through the exit orifice about the conical head of the pintle. The injector further includes a swirler configured to create a swirling action in the flow of pressurized fuel through the fuel manifold, wherein the manifold is upstream of the exit orifice.

First claim

What is claimed is:

1. A fuel injector apparatus, comprising:
an injector body having a bore therethrough, the bore defining a fuel manifold;
a variable-area injector arrangement having a pintle with a conical head and a pintle spring operatively connected to the injector body in such a manner that the spring urges the conical head to seal against a variable-area exit orifice located at one end of the body to thereby prevent the passage of pressurized fuel through the variable-area exit orifice, and such that application of pressurized fuel within the injector body causes the pintle to move such that the conical head of the pintle is moved out of contact with the variable-area exit orifice of the body as a function of the pressure of the pressurized fuel in the injector body, to thereby provide a corresponding variable area for passage of the pressurized fuel through the variable-area exit orifice about the conical head of the pintle; and
a fuel swirler positioned within the manifold and configured to create a swirling action in the flow of pressurized fuel within the fuel manifold, wherein the fuel manifold is upstream of the variable-area exit orifice.

2. The fuel injector apparatus of claim 1 , wherein the fuel swirler is configured to hold the pintle substantially centered within the injector body.

3. The fuel injector apparatus of claim 2 , wherein the fuel swirler is attached to the injector body by one of brazing and welding.

4. The fuel injector apparatus of claim 2 , wherein the fuel swirler is press fit, threaded or keyed into the bore in the injector body.

5. The fuel injector apparatus of claim 2 , wherein the fuel swirler is held in place by pressure from the pintle spring and by the fuel pressure.

6. The fuel injector apparatus of claim 1 , wherein the amount of pressure needed to move the conical head of the pintle out of contact with the variable-area exit orifice is determined by a pre-load on the pintle spring.

7. The fuel injector apparatus of claim 6 , wherein the pre-load is placed on the pintle spring by a retaining nut assembly.

8. The fuel injector of claim 7 , wherein the retainer nut assembly comprises a retaining nut, a washer, and a locking nut.

9. The fuel injector apparatus of claim 1 , wherein the injector body includes a threaded portion to facilitate assembly of the fuel injector into an engine.

10. The fuel injector apparatus of claim 1 , wherein the injector body includes a hexagonal portion.

11. The fuel injector apparatus of claim 1 , wherein the pintle includes a cylindrical portion having conical head at one end.

12. The fuel injector apparatus of claim 11 , wherein the pintle includes a threaded portion onto which a retaining nut assembly can be attached.

13. The fuel injector apparatus of claim 12 , wherein the retaining nut assembly is configured to be threaded onto the threaded portion to place a pre-load on the pintle spring.

14. The fuel injector apparatus of claim 1 , wherein the pintle spring is a coil spring.

15. The fuel injector apparatus of claim 1 , wherein the fuel swirler comprises a cylindrical body having one or more vanes that spiral around an outer surface of the cylindrical body.

16. The fuel injector apparatus of claim 15 , wherein the vanes are integral with the cylindrical body.

17. A fuel injector, comprising:
an injector housing having an opening therethrough, the opening defining a fuel manifold;
an injector arrangement having a pintle with a conical head and a pintle spring operatively connected to the injector housing in such a manner that the spring urges a tip of the pintle to seal against an exit orifice of the body to thereby prevent the passage of pressurized fuel through the exit orifice, the injector arrangement being configured such that the conical head is moved out of contact with the exit orifice as a function of the pressure of the pressurized fuel in the injector housing; and
a fuel swirler coupled to the injector housing and positioned within the fuel manifold, the fuel swirler configured to create a swirling action in the flow of pressurized fuel within the fuel manifold.

18. The fuel injector of claim 17 , wherein the fuel swirler comprises a cylindrical body having one or more integral vanes that spiral around an outer surface of the cylindrical body.

19. The fuel injector of claim 17 , wherein the fuel swirler is configured to hold the pintle substantially centered within the injector housing.

20. The fuel injector of claim 17 , wherein the amount of pressure needed to move the conical head of the pintle out of contact with the exit orifice is determined by a pre-load on the pintle spring.

21. The fuel injector of claim 20 , wherein the pre-load is placed on the pintle spring by a retaining nut assembly.

22. The fuel injector of claim 17 , wherein the injector housing includes a threaded portion to facilitate assembly of the fuel injector into an engine.

23. The fuel injector of claim 17 , wherein the pintle includes a cylindrical portion having the conical head at one end, and further includes a threaded portion, at the other end, onto which a retaining nut assembly can be attached.

24. The fuel injector of claim 17 , wherein the fuel swirler comprises a cylindrical plug having a cylindrical body, a shoulder portion, and a plurality of angled holes configured to create a swirling motion in fuel exiting from the plurality of angled holes.

25. The fuel injector of claim 24 , wherein the cylindrical body is configured to fit into the opening in the injector housing, and wherein the shoulder portion is configured to abut an end of the injector housing.

Assignees

• Hicks Paul G
• Woodward Inc

Inventors

• Hicks Paul G

Classifications

• F01N2610/1453

  Sprayers or atomisers; Arrangement thereof in the exhaust apparatus · CPC title

• F23D11/26

  with provision for varying the rate at which the fuel is sprayed · CPC title

• F23D11/383 Primary

  with swirl means · CPC title