Claims:We Claim:
1. An electrical gear pump (10) for a fuel injection system, said electrical gear pump (10) comprising:
a housing (12);
at least one stator (14) positioned within said housing (12);
at least one G-rotor (16) disposed within said stator (14);
a hydraulic conduit block (18) having a fuel inlet (24) and a fuel outlet (25) disposed against a first surface of said housing (12), the first surface of said housing (12) perpendicular to an axis of said rotor; characterized in that
a pump control unit (20) abutting against a second surface of said housing (12) and said hydraulic conduit block (18), the second surface of said housing (12) perpendicular to said first surface, said pump control unit (20) adapted to control a flow of fuel out of said electrical gear pump (10).
2. The electrical gear pump (10) for the fuel injection system in accordance with Claim 1 further comprising an electrical interface (22) in electronic communication with said pump control unit (20), said electrical interface (22) adapted to supply electric power to said pump control unit (20).
3. The electrical gear pump (10) for the fuel injection system in accordance with Claim 1, the fuel inlet (24) adapted to supply fuel to said at least one G-rotor (16), and the fuel outlet (25) adapted to withdraw fuel from said at least one G-rotor (16) of said gear pump (10), said fuel inlet (24) and said fuel outlet (25) parallel to the second surface of said housing.
, Description:Field of the invention
[0001] This invention relates to a gear pump and more particularly to a gear pump for a fuel injection system.
Background of the invention
[0002] IN02023CH2015A describes a fuel delivery assembly for a common rail fuel injection system. The fuel delivery assembly is located in the low pressure circuit of the common rail fuel injection system and comprises at least a filter in fuel communication with a fuel tank, an electrical gear pump, and a pump control unit for the electrical gear pump. The electrical gear pump is adapted to be controlled by the pump control unit for metering flow of fuel through the electrical gear pump in dependence of the amount of fuel to be delivered to the inlet of a high pressure pump of the common rail fuel injection system.
Brief description of the accompanying drawings
[0003] Figure 1 illustrates a schematic diagram of a gear pump for a fuel injection system.
[0004] Figure 2 illustrates a schematic diagram of a top view of the gear pump for the fuel injection system.
Detailed description of the invention
[0005] An electrical gear pump 10 for a fuel injection system is described. The electrical gear pump 10 comprises a housing 12 and at least one stator 14 positioned within the housing 12. At least one G-rotor 16 is disposed within the stator 14. A hydraulic conduit block 18 having a fuel inlet 24 and a fuel outlet 25 is disposed against a first surface of the housing 12, the first surface of the housing 12 perpendicular to an axis of the rotor. A pump control unit 20 abuts against a second surface of the housing 12 and the hydraulic conduit block 18, the second surface perpendicular to the first surface of the housing 12, the pump control unit 20 adapted to control a flow of fuel out of the electrical gear pump 10.
[0006] Figure 1 illustrates a schematic diagram of a gear pump 10 for a fuel injection system. The gear pump 10 comprises a housing 12. At least one stator 14 is positioned within the housing 12. A G-rotor 16 is disposed within each stator 14, and is activated by the stator 14. Therefore, the stator 14 facilitates activating the G-rotor 16 of the gear pump 10. A hydraulic conduit block 18 is disposed against a first surface of the housing 12. More specifically, a fuel inlet 24 is in flow communication with the hydraulic conduit block 18 and supplies fuel to the hydraulic conduit block 18. From the hydraulic conduit block 18, the fuel is channeled to the G-rotor 16 of the gear pump 10. After the fuel is compressed by the G-rotor 16 of the gear pump 10, the compressed fuel is supplied to a fuel outlet 25. From the fuel outlet 25, the compressed fuel is delivered to a high pressure pump (not shown) for additional fuel compression.
[0007] The gear pump 10 for the fuel injection system comprises a pump control unit 20 that is coupled to the housing 12 and the hydraulic conduit block 18. More specifically, the pump control unit 20 abuts against a second surface of the housing 12 and the hydraulic conduit block 18. The second surface of the housing 12 is perpendicular to the first surface of the housing 12. The second surface of the housing 12 being a side of the housing 12, the pump control unit 20 is coupled to the side of the housing 12. The pump control unit 20 is adapted to control a flow of fuel out of the gear pump 10. In an exemplary embodiment, the pump control unit 20 is secured to the housing 12 and the hydraulic conduit block 18 via any fastening means that is known in the art. The pump control unit 20 is in electronic communication with each stator 14 via a control flow path 28 and supplies electric power to each stator 14 to facilitate activating each G-rotor 16. Due to the close proximity of the pump control unit 20 from each stator 14, the control flow path 28 is short in length as compared to known electrical gear pumps.
[0008] An electrical interface 22 is in electronic communication with the pump control unit 20. More specifically, the electrical interface 22 is in electronic communication with an engine control unit (not shown) and receives electronic signals from the engine control unit. Based on the signal received from the engine control unit, the electrical interface 22 supplies electric power to pump control unit 20. Therein, the pump control unit 20 activates each stator 14 via the control flow path 28.
[0009] Figure 2 illustrates a schematic diagram of a top view of the gear pump 10 for the fuel injection system. The gear pump 10 comprises the pump control unit 20 that is secured to the hydraulic conduit block 18. A fuel inlet 24 and a fuel outlet 25 is coupled to the hydraulic conduit block 18.The fuel inlet 24 and the fuel outlet 25 are parallel to the second surface and contain reduced number of bends, thereby improving the volumetric efficiency of the gear pump 10.
[0010] The electrical interface 22 is in electronic communication with the pump control unit 20 as described earlier. A fastening means 30 is secured to the hydraulic conduit block 18 and is used to secure the hydraulic conduit block 18 to a housing of the engine. In an exemplary embodiment, any fastening means that is known in the art may be used to secure the hydraulic conduit block 18 to the engine. In the embodiment shown in Figure 2, the hydraulic conduit block 18 is secured to the engine by means of a screw.
[0011] A working of the gear pump 10 for the fuel injection system is described as an example. When it is desired to operate the gear pump 10, the engine control unit transmits a signal to the pump control unit 20 by means of the electrical interface 22. The pump control unit 20 in turn activates the stator 14 via the control flow path 28. The stator 14 activates each G-rotor 16 that creates a low pressure region in each G-rotor. The low pressure region created in each G-rotor 16 causes a suction in the fuel inlet 24. The suction created in the fuel inlet 24 causes fuel to be channeled into the G-rotor 16 from a fuel tank, wherein the G-rotor 16 pressurizes the fuel for delivery. Pressurized fuel is supplied from the G-rotor 16 to the fuel outlet 25 of the gear pump 10 where it is delivered to a high pressure fuel pump for further pressurization. The advantages of the present invention is that as the pump control unit 20 abuts against the second surface of the housing, the gear pump 10 is extremely compact with a substantially reduced height of the hydraulic conduit block 18 as compared to gear pumps that are known in the art. In addition, the fuel inlet 24 and the fuel outlet 25 are parallel to the second surface of the housing thereby increasing the volumetric efficiency of the gear pump 10. The reduction in the number of bends of the fuel inlet 24 and the fuel outlet 25 improves the volumetric efficiency of the gear pump 10.
[0012] It must be understood that the embodiments explained above are only illustrative and do not limit the scope of the disclosure. Many modifications in the embodiments with regard to leverage and dimensions of various components are envisaged and form a part of this invention. The scope of the invention is only limited by the claims.