Field of the invention
[0001] This invention relates to the field of connectors for dosing fuel for enabling hydro carbon injection.
Background of the invention
[0002] A fuel control unit is consists of a housing, which carries a metering unit to meter fuel to the high pressure pump via a outlet connector. It also houses an overflow valve and sometimes a throttle & a connection back to the tank after the metering unit. The Fuel control unit has an inlet connector.
[0003] In the low pressure circuit of the fuel injection system, Fuel control unit is placed before the main high pressure pump. The fuel is fed to the main pump through the Fuel control unit, which the fuel control unit receives fuel from the feed pump either placed in the tank or in the low pressure line upstream of Fuel control unit.
[0004] By taking an additional connection from the fuel control unit before the metering unit, either by a separate outlet connector on the fuel control unit or a modified inlet connector, some amount of fuel can be diverted to a HCI (hydro carbon injection) dosing injector or module for dosing HCI into exhaust for regeneration of after treatment system.
Brief description of the accompanying drawing
[0005] Different modes of the invention are disclosed in detail in the description and illustrated in the accompanying drawing:
[0006] FIG. 1 illustrates an inlet connector for a fuel control unit; and
Detailed description of the embodiments
[0007] FIG. 1 illustrates an inlet connector 100 for a fuel control unit 102. The fuel control unit 102 is located downstream from a fuel tank 104 and upstream from

a fuel injection pump 106, and comprises at least an inlet 108 adapted to receive fuel from the fuel tank 104 through a second opening 110 of an inlet connector, the first opening 112 of inlet connector 100 is in flow communication with the fuel tank 104. The inlet connector 100 comprises a third opening 114, the third opening 114 is in flow communication with a dosing line 116. The dosing line 116 is in flow communication with a dosing injector for injecting the fuel into an exhaust path for hydro-carbon injection.
[0008] The constructional details and function of the inlet connector 100 used in the fuel control unit 102 will be explained in further detail. The inlet connector 100 for the fuel control unit 102, connects fuel tank 104 with the fuel control unit 102. The inlet connector 100 is connected to the fuel tank 104 through the first opening 112. The second opening 110 of the inlet connector 100 is connected to the fuel control unit 102. The inlet connector 100 has a third opening 114 that is located before the fuel control unit 102. The dosing line 116 is connected to the third opening 114. The dosing line 116 is in flow communication with the dosing inj ector.
[0009] FIG. 2 illustrates a fuel injection system 200. The fuel injection system 200 comprises a fuel tank 202, a fuel control unit 204 located downstream from a fuel tank 202 and upstream from a fuel injection pump 206 The fuel control unit 204 receives fuel from an inlet connector 208, the fuel injection pump 206 is in flow communication with a rail 210. The inlet connector 208 is adapted to supply fuel to a dosing injector 212 for hydro-carbon injection, the dosing injector 212 is located external to the fuel injection system 200.
[00010] The working of the fuel injection system 200 with reference to FIG. 2 will now be explained in further detail. The primary function of the fuel injection system 200, is to ensure that the fuel is pressurized to an adequate extent that is so required for combustion to happen in the engine cylinder. In addition to this, the proposed fuel injection system 200 is configured so as to enable combustion to happen in the exhaust path. This is the additional functionality that is satisfied in

the proposed fuel injection system 200. The working of the fuel injection system 200 will be explained with reference to a) flow of fuel within the system for the purpose of supplying pressurized fuel to the common rail/ injector, and b) flow of fuel from the fuel injection system to a component (dosing injector 212) located outside the fuel injection system 200.
[00011] Fuel flow from the fuel tank 203 flows through a feed pump to reach the metering unit. The metering unit decides the amount of fuel that needs to be delivered to the inlet of the fuel injection pump 206. The fuel injection pump 206 pressurizes the pump and sends the pressurized fuel to the rail 210. Fuel from the rail 210 is injected into the engine cylinder for combustion to happen, the exhaust from combustion passes through the exhaust path. This exhaust contains hydro¬carbons that needs to be burnt in order to satisfy the emission norms. This happens through hydro-carbon injection (HCI). An injector also called as dosing injector 212 is located along the exhaust path. The pressure at which fuel needs to be supplied to the dosing injector 212 is comparatively less than pressure required for high pressure injection in the injector for combustion in the engine cylinder. Hence, instead of using high pressure fuel that is being delivered to the rail 210, a part of the fuel that flows from the feed pump to the fuel control unit is now diverted to supply fuel to the dosing injector 212.
[00012] 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 design of inlet connector used and the type of inlet connector used. 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.
Claims:We Claim:
1. An inlet connector (100) for a fuel control unit (102):
said fuel control unit (102) located downstream from a fuel tank (104) and upstream from a fuel injection pump (206), and comprising at least an inlet (108) adapted to receive fuel from said fuel tank (104) through a second opening (110) of an inlet connector, said first opening (112) of inlet connector in flow communication with said fuel tank (104);
characterized in that:
said inlet connector comprising a third opening (114), said third opening (114) in flow communication with a dosing line (116), said dosing line in flow communication with a dosing injector (118) for injecting said fuel into an exhaust path for hydro-carbon injection.

2. The inlet connector of claim 1, wherein a T-joint is provided in said third opening (114).

3. The inlet connector of claim 1, wherein said inlet connector is integrated with said fuel control unit (102).

4. A fuel injection system (200), comprising at least:

a fuel tank (202);
a fuel filter (203)
a fuel control unit (204) located downstream from a fuel tank (202) and upstream from a fuel injection pump (206), said fuel control unit adapted to receive fuel from an inlet connector (208);
said fuel injection pump 206 in flow communication with a rail (210);
characterized in that
said inlet connector (208) adapted to supply fuel to a dosing injector (212) for hydro-carbon injection, said dosing injector located external to said fuel injection system (200). , Description:Field of the invention
[0001] This invention relates to the field of connectors for dosing fuel for enabling hydro carbon injection.
Background of the invention
[0002] A fuel control unit is consists of a housing, which carries a metering unit to meter fuel to the high pressure pump via a outlet connector. It also houses an overflow valve and sometimes a throttle & a connection back to the tank after the metering unit. The Fuel control unit has an inlet connector.
[0003] In the low pressure circuit of the fuel injection system, Fuel control unit is placed before the main high pressure pump. The fuel is fed to the main pump through the Fuel control unit, which the fuel control unit receives fuel from the feed pump either placed in the tank or in the low pressure line upstream of Fuel control unit.
[0004] By taking an additional connection from the fuel control unit before the metering unit, either by a separate outlet connector on the fuel control unit or a modified inlet connector, some amount of fuel can be diverted to a HCI (hydro carbon injection) dosing injector or module for dosing HCI into exhaust for regeneration of after treatment system.
Brief description of the accompanying drawing
[0005] Different modes of the invention are disclosed in detail in the description and illustrated in the accompanying drawing:
[0006] FIG. 1 illustrates an inlet connector for a fuel control unit; and
Detailed description of the embodiments
[0007] FIG. 1 illustrates an inlet connector 100 for a fuel control unit 102. The fuel control unit 102 is located downstream from a fuel tank 104 and upstream from a fuel injection pump 106, and comprises at least an inlet 108 adapted to receive fuel from the fuel tank 104 through a second opening 110 of an inlet connector, the first opening 112 of inlet connector 100 is in flow communication with the fuel tank 104. The inlet connector 100 comprises a third opening 114, the third opening 114 is in flow communication with a dosing line 116. The dosing line 116 is in flow communication with a dosing injector for injecting the fuel into an exhaust path for hydro-carbon injection.
[0008] The constructional details and function of the inlet connector 100 used in the fuel control unit 102 will be explained in further detail. The inlet connector 100 for the fuel control unit 102, connects fuel tank 104 with the fuel control unit 102. The inlet connector 100 is connected to the fuel tank 104 through the first opening 112. The second opening 110 of the inlet connector 100 is connected to the fuel control unit 102. The inlet connector 100 has a third opening 114 that is located before the fuel control unit 102. The dosing line 116 is connected to the third opening 114. The dosing line 116 is in flow communication with the dosing injector.
[0009] FIG. 2 illustrates a fuel injection system 200. The fuel injection system 200 comprises a fuel tank 202, a fuel control unit 204 located downstream from a fuel tank 202 and upstream from a fuel injection pump 206 The fuel control unit 204 receives fuel from an inlet connector 208, the fuel injection pump 206 is in flow communication with a rail 210. The inlet connector 208 is adapted to supply fuel to a dosing injector 212 for hydro-carbon injection, the dosing injector 212 is located external to the fuel injection system 200.
[00010] The working of the fuel injection system 200 with reference to FIG. 2 will now be explained in further detail. The primary function of the fuel injection system 200, is to ensure that the fuel is pressurized to an adequate extent that is so required for combustion to happen in the engine cylinder. In addition to this, the proposed fuel injection system 200 is configured so as to enable combustion to happen in the exhaust path. This is the additional functionality that is satisfied in the proposed fuel injection system 200. The working of the fuel injection system 200 will be explained with reference to a) flow of fuel within the system for the purpose of supplying pressurized fuel to the common rail/ injector, and b) flow of fuel from the fuel injection system to a component (dosing injector 212) located outside the fuel injection system 200.
[00011] Fuel flow from the fuel tank 203 flows through a feed pump to reach the metering unit. The metering unit decides the amount of fuel that needs to be delivered to the inlet of the fuel injection pump 206. The fuel injection pump 206 pressurizes the pump and sends the pressurized fuel to the rail 210. Fuel from the rail 210 is injected into the engine cylinder for combustion to happen, the exhaust from combustion passes through the exhaust path. This exhaust contains hydro-carbons that needs to be burnt in order to satisfy the emission norms. This happens through hydro-carbon injection (HCI). An injector also called as dosing injector 212 is located along the exhaust path. The pressure at which fuel needs to be supplied to the dosing injector 212 is comparatively less than pressure required for high pressure injection in the injector for combustion in the engine cylinder. Hence, instead of using high pressure fuel that is being delivered to the rail 210, a part of the fuel that flows from the feed pump to the fuel control unit is now diverted to supply fuel to the dosing injector 212.
[00012] 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 design of inlet connector used and the type of inlet connector used. 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.