Claims:We Claim:
1. A fuel injection pump , comprising at least:
a housing (102) enclosing a plunger; and
a pump shaft (104) adapted to receive rotary motion from an engine crank shaft (106) and drive said plunger, characterized in that:
at least one arc spring (108) located concentric to said pump shaft (104), a first end (103) of said arc spring (108) connected to said pump shaft (104);
a gear (110) disposed co-axial to said pump shaft and connected to a second end (105) of said arc spring 108.

2. The fuel injection pump of claim 1, wherein said gear (110) is engaged to a drive gear (112), said drive gear (112) mounted on a crankshaft of an engine.
, Description:Complete Specification:

The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed.
Field of the invention
[0001]This invention relates to the field of fuel injection pump.

Background of the invention
[0002]A fuel injection pump is used to pressurize fuel received from a fuel tank and direct the pressurized fuel for injection into the engine cylinder. A plunger located in the fuel injection pump pressurizes the fuel, the plunger is driven by a cam mounted on a cam shaft. The cam shaft is driven by an engine crank shaft. The vibrations from the engine crankshaft is transferred to the cam shaft. Also, since the cam shaft and the crank shaft are connected with the help of belt and/ or chain drives, failure in one of the drive mechanism leads to loss of transmission from the engine crank shaft to the cam shaft of the fuel injection pump. Hence, there is need to ensure that the vibrations from the engine are not transferred to the fuel injection pump and also to ensure uninterrupted transfer of motion from the engine crankshaft to the fuel injection pump.

Brief description of the accompanying drawing
[0003] Different modes of the invention are disclosed in detail in the description and illustrated in the accompanying drawing:

[0004] FIG. 1 illustrates a fuel injection pump.

Detailed description of the embodiments
[0005] FIG. 1 illustrates a fuel injection pump. The fuel injection pump comprises a housing 102 enclosing a plunger, a pump shaft 104 adapted to receive rotary motion from an engine crank shaft 106 and drive the plunger. At least one arc spring 108 is located concentric to the pump shaft 104. A first end 103 of the spring is connected to the pump shaft 104. A gear 110 is disposed coaxial to the pump shaft 104 and connected to a second end 105 of the arc spring 108.

[0006]The working of the fuel injection pump will be explained in further detail. The fuel injection pump comprises a plunger. In order to pressurize the fuel within the fuel injection pump, the plunger needs to reciprocate within the housing 102. The drive to the plunger happens through the rotation of the pump shaft 104. The pump shaft 104 is a driven shaft, in other words, the pump shaft 104 receives rotary motion via an arc spring 108 and a gear. The gear is adapted to receive motion from the engine crank shaft 106, also called as the drive shaft. Mounted on the drive shaft is a drive gear 112. The drive gear 112 is engaged to the gear that is disposed co-axial to the pump. The rotation of the drive gear 112 on the crank shaft 106 causes the gear that is located co-axial to the pump to rotate. The rotational force on the gear is transferred to the second end 105 of the arc spring 108. The second end 105 of the arc spring 108 transfers the rotary motion to the pump shaft 104 through the first end 103 of the spring. This causes the pump shaft 104 to rotate, the rotation of the pump shaft 104 results in reciprocatory movement of the plunger.

[0007]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 the type of pump 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.