CLIAMS:We Claim:

1. A washer (12) for a fuel injector (10), said washer (12) comprising:
a first surface (14) and an opposite second surface (16), the first surface (14) defining a groove (18), said washer (12) is fitted to a nozzle (20) of said fuel injector (10), and a lock nut fastens said nozzle (20) to a fuel injector body of said fuel injector (10); characterized in that
a gasket (22) inserted within said groove (18) of said washer (12), said gasket (22) prevents exhaust gas from flowing to a collar (24) located about said nozzle (20) of said fuel injector (10).
2. The washer (12) for a fuel injector (10) in accordance with Claim 1, wherein a thickness of said gasket (22) is greater than a depth of said groove (18) of said washer (12).
3. The washer (12) for a fuel injector (10) in accordance with Claim 2, wherein a clearance (26) is provided between said nozzle (20) of said fuel injector (10) and said washer (12), the clearance (26) adapted to accommodate said gasket (22) when said washer (12) is pressed against said collar (24) of said nozzle (20) of said fuel injector (10).
4. A fuel injector (10), said fuel injector (10) comprising:
a nozzle (20) coupled to a fuel injector body of said fuel injector (10), and a lock nut that fastens said nozzle (20) to said fuel injector body of said fuel injector (10);
a washer (12) fastened to said nozzle (20) of said fuel injector (10), said washer (12) comprising a groove (18) defined therein; characterized in that
a gasket (22) inserted within said groove (18) of said washer (12), said gasket (22) prevents exhaust gas from flowing to a collar (24) located about said nozzle (20) of said fuel injector (10).
5. The fuel injector (10) in accordance with Claim 4, wherein a thickness of said gasket (22) is greater than a depth of said groove (18) of said washer (12).
6. The fuel injector (10) in accordance with Claim 5, wherein a clearance (26) is defined between said nozzle (20) of said fuel injector (10) and said washer (12), the clearance (26) adapted to accommodate said gasket (22) when said washer (12) is pressed against said collar (24) of said nozzle (20) of said fuel injector (10).
,TagSPECI:Field of the invention
[0001] This invention relates to a fuel injector and a gasket thereof.

Background of the invention
[0002] A fuel injector includes a nozzle that sprays fuel into an engine cylinder. A sealing copper washer is coupled to the nozzle to prevent exhaust gas from the engine cylinder escaping past the fuel injector. However, the exhaust gas from the engine cylinder flows upwardly through a clearance defined between the washer and the nozzle. The corrosive particles present in the exhaust gas are deposited on a collar of the nozzle. Over a period of time, the collar of the nozzle undergoes pitting corrosion and experiences high stress concentration. This in combination with hydraulic and mechanical loads result in the nozzle breakdown. To avoid pitting corrosion on the collar of the nozzle of the fuel injector, a gasket that prevents exhaust gas leakage is required to be inserted within a groove defined in the washer.

[0003] U.S. Publication Number 2009/0261286-A1 describes an assembly 54 that has a recess placed on an interior surface of a housing. A valve supporting element is placed within the housing. A washer is placed within the housing, where the washer comprises a washer surface and a projection for transferring torque. The washer surface buts against a valve supporting element surface of the valve supporting element and the projection received in the recess. A fastener e.g. screw is placed within the housing and comprises a fastener surface abutting against another washer surface of the washer.

Brief description of the accompanying drawings
[0004] Different modes of the invention are disclosed in detail in the description and illustrated in the accompanying drawing:

[0005] Figure 1 illustrates a gasket inserted within a groove of a washer in a fuel injector.
Detailed description of the embodiments

[0006] Figure 1 illustrates a washer 12 for a fuel injector 10. The washer 12 comprises a first surface 14 and an opposite second surface 16. The first surface 14 defines a groove 18, and wherein the washer 12 is fitted to a nozzle 20 of the fuel injector 10. A lock nut fastens the nozzle 20 to a fuel injector body of the fuel injector 10. A gasket 22 is inserted within the groove 18 of the washer 12. The gasket 22 prevents exhaust gas from flowing to a collar 24 located about the nozzle 20 of the fuel injector 10.

[0007] In addition, a fuel injector 10 is described. The fuel injector 10 comprises a nozzle 20 coupled to a fuel injector body of the fuel injector 10, and a lock nut that fastens the nozzle 20 to the fuel injector body of the fuel injector 10. A washer 12 is fastened to the nozzle 20 of the fuel injector 10, the washer 12 comprising a groove 18 defined therein. A gasket 22 is inserted within the groove 18 of the washer 12. The gasket 22 prevents exhaust gas from flowing to a collar 24 located aboutthe nozzle 20 of the fuel injector 10.

[0008] Figure 1 is a schematic representation of a fuel injector 10. The fuel injector 10 includes a fuel injector body, and a nozzle 20 coupled to the fuel injector body. A lock nut fastens the nozzle 20 to the fuel injector body of the fuel injector 10.

[0009] The washer 12 is inserted through the nozzle 20 of the fuel injector 10. The washer 12 includes an upper surface 14 and a lower surface 16. A clearance 26 is defined between the washer 12 and the nozzle 20. A groove 18 is defined on the upper surface 14 of the washer 12. A gasket 22 is inserted within the groove 18 defined on the upper surface 14 of the washer 12. A thickness of the gasket 22 is larger than a depth of the groove 18. An upper surface of the gasket 22 is in sealing contact with a collar 24 of the nozzle 20. When the washer 12 is pressed against the collar 24 of the nozzle 20, the gasket 22 seals the space between collar 24 of the nozzle 20 and the washer 12. Therefore, the gasket 22 is flush against the upper surface 14 of the washer 12 and seals the clearance 26 provided between the washer 12 and the nozzle 20.

[00010] The principle of working of the gasket 22 for the washer 12 of the fuel injector 10 is now explained as an example. When the washer 12 is pressed against the collar 24 of the nozzle 20, the gasket 22 presses against the collar 24 of the nozzle 20. Therein, the gasket 22 is flush against the upper surface 14 of the washer 12. The gasket 22 that is compressed between a surface of the groove 18 and the collar 24 of the nozzle 20 is squeezed through the clearance 26 provided between the nozzle 20 and the washer 12, thereby sealing the clearance 26 between the washer 12 and the nozzle 20. When exhaust gas is released from the engine cylinder, the exhaust gas cannot flow through the clearance 26 provided between the nozzle 20 and the washer 12. Therefore, exhaust gas particles are not deposited on the collar 24 of the nozzle 20, thereby extending the useful life of the nozzle 20.

[00011] Using the device of the present invention, the life of the nozzle 20 may be extended to an extent that is much greater than if the gasket 22 were not inserted within the groove 18 of the washer 12. Moreover, the use of the gasket 22 is inexpensive, making it a cost effective method of enhancing a useful life of the nozzle 20. This is important since the useful life of the nozzle 20 is required to be extended by avoiding pitting corrosion.

[00012] The above described gasket 22 for a washer 12 of a fuel injector 10 facilitates preventing particles from the exhaust gas from being deposited on the collar 24 of the fuel injector 10. Therefore, the longevity and useful life of the nozzle 20 of the fuel injector 10 is substantially increased.

[00013] It must be understood that the embodiments explained in the above detailed description is only illustrative and does not limit the scope of this invention. The scope of this invention is limited only by the scope of the claims. Many modification and changes in the embodiments aforementioned are envisaged and are within the scope of this invention.