Field of the invention:
The present invention relates to a gravity-fed fuel injection system for a vehicle and a mounting arrangement of a fuel injection module.
Background of the invention:
A gravity-fed fuel injection system has no pump or fuel supply module, therefore the droplet size of the fuel is bigger than the pressurized system. This directly impacts the mixture preparation in the intake manifold of an engine of a vehicle. The mixture preparation can be relatively improved by selecting an appropriate mounting location and orientation of mounting in the intake manifold of the engine.
According to a prior art 3875/CHE/2013, a pulse count injector (PCI) module is disclosed. The PCI module comprises a PCI holder and a PCI cover which form a PCI housing to enclose the PCI. The PCI module further includes a fuel inlet adapter; a fuel chamber is formed between the PCI and said PCI housing, a vapor separator and a fuel outlet. The PCI module in accordance with one embodiment of the invention can replace the existing gasoline fuel injector without major changes to the intake manifold or the existing throttle body assembly.
Brief description of the accompanying drawings:
[0004] An embodiment of the disclosure is described with reference to the following accompanying drawing,
[0005] Fig. 1 illustrates a gravity-fed fuel injection system, according to an embodiment of the present invention.
Detailed description of the embodiments:
[0006] Fig. 1 illustrates a gravity-fed fuel injection system, according to an embodiment of the present invention. The system 100 comprises a fuel tank 102, a fuel injection module 110 having the Pulse Count Injector (PCI). The PCI (not shown) is electronically controlled by a controller, such as Engine Control Unit

(ECU). The fuel injection module 110 is connected to and between the fuel tank 102 and an intake manifold 108. The system 100 is characterized by, the fuel injection module 110 mounted on the intake manifold 108 within a distance of ten times a diameter 112 of the intake manifold 108 from an intake valve 124 of the engine 114. The fuel injection module 110 is also referred to as Unified Pump Injector (UPI), because the fuel injection module 110 functions as a pump and an injector. Specifically, the distance is considered from the seat of the intake valve 124. The seat is provided in the engine block.
[0007] The fuel injection module 110 is mountable to a port 122 of the intake manifold 108 through a threaded mechanism. The port 122 comprises threads on an inner surface to accommodate a connection of the fuel injection module 110. Further, the fuel injection module 110 is mounted to the port 122 of the intake manifold 108 at an angle towards the intake valve 124 of the engine 114. The fuel injection module 110 comprises a fuel reservoir (not shown) within which the PCI is located.
[0008] The Fig. 1 shows the fuel injection module 110 connected to the fuel tank 102 through connecting tubes 118. The fuel injection module 110 receives the fuel from the fuel tank 102 through these connecting tubes 118. Further, an air-filter 104 is connected at the entry of the intake manifold 108. A throttle body 106 is also provided in the intake manifold 108. The throttle body 106 is any one selected from a manually operated or electronically operated. In accordance to an embodiment of the present invention, the fuel injection module 110 is fluidly and directly interfaced/connected to the fuel tank 102 without any connecting tubes 118. Without the connecting tubes 118, the assembly of the fuel injection module 110 between the intake manifold 108 and the fuel tank 102 is simplified and is more economical. The fuel injection module 110 further comprises a conduit 116 to vent fuel vapors back to the fuel tank 102. The system 100 is preferably applicable for vehicle which is a two-wheeler, equipped with at least one cylinder engine 114, but not limited thereto.

[0009] According to an embodiment of the present invention, a mounting arrangement 120 of the fuel injection module 110 in the vehicle is disclosed. The fuel injection module 110 is part of the gravity-fed fuel injection system 100. The fuel injection module 110 is mounted on the intake manifold 108 of the engine 114 of the vehicle. The mounting arrangement 120 is characterized by, the fuel injection module 110 is mounted within a distance of ten times the diameter 112 of the intake manifold 108 from the intake valve 124 of the engine 114. The distance is considered from the seat of the intake valve 124. The seat is provided in the engine block.
[0010] The mounting arrangement 120 further comprises the fuel injection module 110 to be fluidly and directly connected to the fuel tank 102 of the vehicle.
[0011] According to the present invention, the mixture preparation is improved by positioning the fuel injection module 110 as per the aforesaid mounting location and orientation of mounting from the intake valve 124 of the engine 114. With mounting location close to intake of the engine 114, the targeted spray utilizes the heat from hot surface to vaporize which improves the mixture preparation. Thus, avoiding the need of high injection pressure and low injector outlet diameter.
[0012] The fuel injection module 110 is mounted on the intake manifold 108 of the engine 114. The injected fuel mixes with the air when the intake valve 124 opens and enters the engine 114. The droplet size of the injected fuel and quality of the mixture depends on the mounting location, injector outlet diameter (orifice plate), pressure at which fuel is injected, air velocity, injector orientation etc. The quality of the mixture impacts the air fuel ratio, Hydro Carbon (HC) emissions and drivability. The position, orientation and distance to the intake valve 124 directly impacts the mixture preparation, and the present invention discloses the same to achieve the optimal performance.

[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.

We claim:
1. A gravity-fed fuel injection system (100) for a vehicle, said system (100)
comprising:
a fuel tank (102);
a fuel injection module (110) having a Pulse Count Injector (PCI),
said PCI electronically controlled by a controller, said fuel injection
module (110) connected to and between said fuel tank (102) and an
intake manifold (108),
characterized by
said fuel injection module (110) mounted on said intake manifold (108) within a distance of ten times a diameter (112) of said intake manifold (108) from an intake valve (124) of said engine (114).
2. The system (100) as claimed in claim 1, wherein said fuel injection module (110) is mountable to a port (122) of said intake manifold (108) through a threaded mechanism.
3. The system (100) as claimed in claim 2, wherein said port (122) comprises threads on an inner surface to accommodate a connection of said fuel injection module (110).
4. The system (100) as claimed in claim 1, wherein said fuel injection module (110) is mounted to a port (122) of said intake manifold (108) at an angle towards said intake valve (124) of said engine (114).
5. The system (100) as claimed in claim 1, wherein said fuel injection module (110) comprises a fuel reservoir within which said PCI is located.
6. The system (100) as claimed in claim 1, wherein said fuel injection module (110) is fluidly and directly interfaced with said fuel tank (102).

7. The system (100) as claimed in claim 1, wherein said fuel injection module (110) comprises a conduit (116) to vent fuel vapors back to said fuel tank (102).
8. The system (100) as claimed in claim 1, wherein said vehicle is a two-wheeler, equipped with at least one cylinder engine (114).
9. A mounting arrangement (120) of an fuel injection module (110) in a vehicle, said fuel injection module (110) is part of a gravity-fed fuel injection system (100), said fuel injection module (110) mounted on an intake manifold (108) of an engine (114) of said vehicle, characterized by
said fuel injection module (110) is mounted within a distance of ten times a diameter (112) of said intake manifold (108) from an intake valve (124) of said engine (114).
10. The mounting arrangement (120) as claimed in claim 9, wherein said fuel
injection module (110) is fluidly and directly connected to a fuel tank (102)
of said vehicle.