CLIAMS:I claim:
1. A fuel injector nozzle (10) for a fuel injector (12), said fuel injector nozzle (10) fitted to a nozzle holder (14) of said fuel injector (12), said fuel injector nozzle (10) comprising:
- a bore (16) adapted to accommodate a needle (18) within;
- a fuel flow path (20) adapted to allow fuel to flow towards said needle (18);
characterized in that
a barfilter (22) located in said fuel flow path (20) of said fuel injector nozzle (10), said barfilter (22) adapted to trap particulate matter present in fuel.

2. A fuel injector (12), said fuel injector comprising:
- a nozzle holder (14); and
- a fuel injector nozzle (10) fitted to said nozzle holder (14);
characterized in that
a barfilter (22) is located in said fuel injector nozzle (10), said barfilter (22) adapted to trap particulate matter present in fuel.
,TagSPECI:Complete specification: The following specification particularly describes the invention and the manner in which it is to be performed.

Field of the invention
[001] This disclosure relates to a fuel injector nozzle.
Background of the invention:
[002] EP1787021 discloses a filter which prevents the holes of the injector nozzle from being clogged. The filter has a collection volume which has a structure to allow accumulation of solid particles. The external surface of the needle of the injector covers a portion of the holes provided on the filter when the needle is in closed position, thus changing the cross-section of flow in the course of injection process proceeding from the start of injection and that hence a step-by-step injection becomes possible.

Brief description of the accompanying drawings:
[003] An embodiment of the disclosure is described with reference to the following accompanying drawings;
[004] Figure 1 illustrates a fuel injector in accordance with this disclosure; and
[005] Figure 2 illustrates a fuel injector nozzle in accordance with this disclosure.
Detailed description of the embodiments:
[006] Figure 1 illustrates a fuel injector in accordance with this disclosure. The fuel injector 12 comprises a nozzle holder 14 and a fuel injector nozzle 10 fitted to the nozzle holder 14. The fuel injector 12 is characterized such that a barfilter 22 is located in the fuel injector nozzle 10. The barfilter 22 is adapted to trap particulate matter present in fuel.

[007] Figure 2 illustrates a fuel injector nozzle 10 for a fuel injector 12. The fuel injector nozzle 10 is fitted to the nozzle holder 14 of the fuel injector 12. The fuel injector nozzle 10 comprises a bore 16 adapted to accommodate a needle 18 within and a fuel flow path 20 adapted to allow fuel to flow towards the needle 18. The fuel injection nozzle 10 is characterized such that a barfilter 22 is located in the fuel flow path 20 of the fuel injector nozzle 10. The barfilter 22 adapted to trap particulate matter present in fuel.

[008] For better understanding of the fuel injector and fuel injection nozzle of this disclosure the following description provides background understanding of a fuel injection system and its components. Fuel injection systems are used in IC engines to inject fuel which is stored in the fuel tank to the engine cylinder through one or more injectors. Also in most cases the fuel cannot be directly injected into the engine cylinder, the fuel needs to be pressurized and then injected. Different components of the fuel injection system help in pressurizing the fuel. The component of the fuel injection system which helps in pressurizing the fuel is the fuel pump. However, even before the fuel reaches the fuel pump from the fuel tank at least one stage of filtration is used to filter out any impurities that may be present in the fuel.

[009] The filtration component used to filter the fuel not only influences the size of the particulate impurities that can be filtered out but also influences the cost of the overall system. More importantly the size of the particulate matter in the fuel also influences the wear and tear that the components of the fuel injection system may be subjected to. In the fuel injection system the effect of the particulate matter in the fuel is most pronounced on the fuel injector. For the purpose of this disclosure we will focus on the particulate matter in the fuel and its effects on the fuel injector.

[0010] The fuel injector has a plurality of components, from the point of view of the particulate matter in the fuel and the component of the fuel injector that are affected by the particulate matter are the various flow paths in the fuel injector, the needle of the fuel injector and the holes provided in the nozzle of the fuel injector. The nozzle of the fuel injector is provided with a plurality of holes which help in injecting fuel into the engine cylinder. Depending on the type of engine (i.e. gasoline or diesel), the fuel injector may inject fuel into the inlet manifold or directly into the engine cylinder.

[0011] For ensuring that the air/fuel mixture that is supplied to the engine cylinder is mixed well, it is required to ensure that the fuel provided by the fuel injector is broken into as small droplets as possible. One way of ensuring this is having the diameter of the holes in the injector as small as possible. However, one of the effects of small very small diameter holes in the injector nozzle is that the particulate matter which is larger than the diameter of the holes in the injector nozzle will get stuck in the holes thereby clogging or narrowing the injector holes. This will lead to insufficient injection of fuel. Due to insufficient injection the engine would be starved of the fuel and efficiency of the fuel will reduce. The insufficient injection may cause deviations from the conditions of forming a proper mixture determined during design and development stage as well as increases in exhaust emissions by affecting the combustion event in the cylinder. The aforesaid narrowing or clogging in the injector nozzle may be due to solid particles or due to wears in pump, fuel line and injector in the fuel injection system, and it also depends on the quality of fuel used. Such a case may cause a substantial increase in maintenance expenses in addition to occurrence of such adversities as loss of power in the engine and increase in exhaust emissions, depending on the aforesaid conditions.

[0012] In accordance with this disclosure the barfilter 22 is provided in the fuel flow path 20 of the fuel injector nozzle 10. The working of the barfilter 22 can be explained as follows. When the fuel flows from the nozzle holder towards the fuel injector nozzle 10, it enters the fuel flow path 20. The barfilter 22 entraps the particulate matter that may be present in the fuel. As the high pressure fuel in the flow path 20 continues to impinge on the entrapped particles are cut into smaller pieces. As the entrapped particles are cut into smaller pieces, these particles do not get caught up into the holes 24 of the fuel injector nozzle 10. This prevents clogging of the holes 24 and possibility of the increasing size of the holes 24 due to wear and tear due to clogging. As clogging is prevented the fuel injector nozzle and the fuel injector life is increased.

[0013] It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention. 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.