Claims:We claim:
1. A fuel injector (10) in a vehicle, said fuel injector (10) comprising;
- a first portion (12) having a multiple threads (18) formed on at least one surface;
- a second portion (14) having a nozzle (38);
- a retaining nut (16) adapted to seal said first portion (12) with said second portion (14), such that, said retaining nut (16) is tightened into said multiple threads (18) formed on said at least one surface of said first portion (12).

2. The fuel injector (10) as claimed in claim 1, wherein said second portion (14) of said fuel injector (10) comprises a high pressure path (20) comprising a first annular groove (28), a low pressure path (22) having a second annular groove (30).

3. The fuel injector (10) as claimed in claim 1, wherein said first portion (12) comprises a corresponding high pressure path (24) and a low pressure path (26) aligned with said high pressure path (20) and said low pressure path (22) of said second portion (14).

4. The fuel injector (10) as claimed in claim 1, wherein a high pressure bore (40) and a low pressure bore (42) of said first portion (12) of said fuel injector (10), swivels on said first annular groove (28) and said second annular groove (30) of said second portion (14).

5. The fuel injector (10) as claimed in claim 1, wherein said first and second annular grooves (28,30) dampens pressure fluctuations during working of said injector (10).

6. The fuel injector (10) as claimed in claim 1, wherein said second portion (14) comprises a sealing area (32) adapted to receive said retaining nut (16) when tightened between said first portion (12) and said second portion (14).
7. The fuel injector (10) as claimed in claim 1, wherein said second portion (14) comprises a leakage safety groove (34) through which said fuel is directed into said low pressure path (22) of said second portion (14).

8. The fuel injector (10) as claimed in claim 8, wherein said fuel flows from said leakage safety groove (34) to said low pressure path (26), upon detection of a leakage in said sealing area (32).
, Description:Field of the invention
[0001] This invention relates to the field of fuel injector in a vehicle.

Background of the invention
[0002] Typical fuel injectors used in, for example, internal combustion diesel engines of automotive vehicles are designed allow a high pressure fuel into a fuel supply passage selectively. When it is required to inject the fuel into the engine, the fuel pressure acting on a needle lifts up the needle for opening a spray hole to initiate the fuel injection. A fuel injector is used to deliver pressurized fuel into the combustion chamber. The fuel injector comprises a casing, one end of the casing receives fuel from the rail. Diesel fuel injector is a single piece body and with a constant high pressure inlet connector orientation with respect to the clamp wrench. Each injector is unique and customized to the specific requirement in terms of mounting and orientation.
[0003] A US patent application 20070084443 discloses a depressurizing valve and fuel injection device. The device comprises a depressurizing valve mounted to a common rail for a fuel injection device, in which a direction of a connector for the depressurizing valve can be adjusted, without affecting an air gap and a sealing performance. The depressurizing valve has a valve unit and a coil unit which is detachably assembled to the valve unit by a mounting member, such as a retaining nut.

Brief description of the accompanying drawing
[0004] Different modes of the invention are disclosed in detail in the description and illustrated in the accompanying drawing:
[0005] Figure 1 illustrates a fuel injector in according to one embodiment of the invention;
[0006] Figures 2(a) & 2(b) illustrates a first portion and a second portion of the fuel injector in according to one embodiment of the invention.

Detailed description of the embodiments
[0007] FIG. 1 illustrates a fuel injector 10 in a vehicle according to an embodiment of the invention. The fuel injector 10 comprises a first portion 12 having a multiple threads 18 formed on at least one surface and a second portion 14 having a nozzle 38. The fuel injector 10 comprises a retaining nut 16 adapted to seal the first portion 12 with the second portion 14, such that, the retaining nut 16 is tightened into the multiple threads 18 formed on at least one surface of the first portion 12.
[0008] The construction of the fuel injector 10 is explained as follows. The fuel injector 10 is located upstream with respect to a combustion engine (not shown). The second portion 14 of the fuel injector 10 comprises a high pressure path 20 having a first annular groove 28 as illustrated in Figure 2(b), a low pressure path 22 comprises a second annular groove 30. The first portion 12 comprises a corresponding high pressure path 24 and a low pressure path 26 aligned with the high pressure path 20 and the low pressure path 22 of the second portion 14 as shown in the figure 2(a). A high pressure bore 40 and a low pressure bore 42 of the first portion 12 of the injector 10, swivels on the first annular groove 28 and the second annular groove 30 of the second portion 14.
[0009] The second portion 14 of the fuel injector 10 comprises a sealing area 32 adapted to receive the retaining nut 16 when tightened between the first portion 12 and the second portion 14 as shown in the figure 2(b). The second portion 14 of the fuel injector 10 further comprises a leakage safety groove 34 through which the fuel is directed into the low pressure path 22 of the second portion 12. The fuel flows from the leakage safety groove 34 to the low pressure path 22, upon detection of a leakage in the sealing area 32. The fuel injector 10 comprises the nozzle 38 in the second portion 12. A needle (not shown) is located within the nozzle 38. The function of the nozzle 38 is to support the needle and also to enable movement of the needle within the nozzle 38.
[0010] The working of the fuel injector 10 is explained in further detail. The fuel is received into the fuel injector 10 from a common rail or a fuel distributor block. The fuel then flows through the high pressure path 24 of the first portion 12 and through the high pressure bore 40 of the first portion 12 into the first annual groove 28 of the second portion 12 and through the high pressure path 20 of the second portion 14 of the fuel injector 10 via the retaining nut 16. Then, the fuel flows into the nozzle 38 for injection. During injection, the needle lifts in a direction away from a sac hole, this causes the fuel to flow from the nozzle into the sac hole. The needle then impinges on the fuel present in the sac hole, causing the fuel to flow into the spray hole for injection into the engine cylinder/ combustion chamber.
[0011] After the injection, the fuel that is remaining in the high pressure path 20 of the second portion 14, flows into the low pressure path 22 of the second portion 14 and through the second annual groove 30, it flows into the low pressure path 26 of the first portion 12. Then, the fuel flows back into a tank via the low pressure path 26 of the first portion 12. The fuel that is leaked in the sealing area 32 during injection, flows back into the tank via the channels 36 and the leakage safety groove 34 present on the sealing area 32 of the second portion 14 of the fuel injector 10.
[0012] With the above disclosed fuel injector, leakages are reduced due to the two-piece design with the retaining nut 16 in between of the first portion 12 and the second portion 14. A variable high pressure inlet connection orientation is possible with the above fuel injector 10. The first and second annular grooves (28,30) dampens pressure fluctuations during working of the fuel injector 10.
[0013] It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention in terms of type of. Many such embodiments and other modifications and changes in the embodiment explained in the description are envisaged. The scope of the invention is only limited by the scope of the claims.
[0014] ‘Adapted’ or ‘arranged’, in the context of the instant disclosure, refers to the technical capability or the technical capacity of a component, in relation to which the term ‘adapted’ or ‘arranged’ is used, to carry out or execute a specified action or actions, upon the requirement of the specified action or actions to be carried out or executed. Moreover, the usage of the term ‘adapted’ or ‘arranged’ here, is in reference with the normal technical capability or technical capacity of the component, imparted by the design or the structure or the composition of the component, and not in reference with any special or extraneous capability or capacity, beyond the scope of the normal technical capability or technical capacity.