Claims:We Claim:
1. A high pressure fuel pump (100) comprising at least a plunger, said plunger (101) having an element (102) comprising gear teeth, characterized in the high pressure fuel pump (100):
a fuel control rod (103) having a first set of gear teeth (104) connected to gear teeth of the element (102);
a second set of gear teeth (105) on the fuel control rod (103);
a push rod (106) adapted to interact with the second set of gear teeth (105);
a spring (107)mounted on the push rod (106) to keep the push rod (106) in position.

2. A high pressure fuel pump (100) as claimed in claim 1, where the push rod (106) interacts with the second set of gear teeth (105) on actuation.
3. A system (200) to fulfill the excess fuel requirement in a vehicle, the system (200) comprising:
A high pressure fuel pump (100) further comprising:
plunger (101) having an element (102) comprising gear teeth;
A fuel control rod (103) having a first set gear teeth along connected to gear teeth of the element (102);
a second set of gear teeth (105) on the fuel control rod (103);
a push rod (106) adapted to interact with the second set of gear teeth (105);
a spring (107)mounted on the push rod (106) to keep the push rod (106) in position.
an actuator (108) placed on the dashboard of the vehicle, said actuator (108) connected to the push rod (106).

4. The system (200) to fulfill the excess fuel requirement in a vehicle as claimed in Claim 1, where the push rod (106) interacts with the second set of gear teeth (105) on actuation.
, 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] The present disclosure relates to a high pressure fuel pump to fulfill excess fuel requirement in a vehicle.

Background of the invention
[0002] A high pressure fuel pump pressurizes fuel coming from the fuel tank. Conventional high pressure fuel pumps comprise at least a plunger and a fuel control rod. The fuel control rod has gear teeth, which connects to the gear teeth of an element of the plunger. In conventional high pressure fuel pumps, the to and fro movement of the fuel control rod regulates the amount of fuel supplied to the plunger of the high pressure fuel pump. In cold weather conditions, achieving a minimum engine rpm requires greater amounts of fuel than that required under normal weather conditions. The present design of the fuel control rod doesn’t allow manual control of the amount of fuel going into the plunger.

[0003] Patent application US5566653A- Method and apparatus for clean cold starting of internal combustion engines discloses improved starting system for internal combustion engines that normally use a liquid fuel such as gasoline. Gaseous fuels such as hydrogen, natural gas, propane, butane and the like are used in place of the liquid fuel during engine starting and for a selected period thereafter. When starting is initiated, the gasoline introduction system is disabled and introduction of the gaseous fuel in initiated. Rapid engine start promptly occurs, even under very cold ambient conditions. Once the engine has started and has run for a period sufficient to reach a reasonable operating temperature, the gaseous fuel introduction system is interrupted and the gasoline system is enabled and provides the fuel thereafter. If desired, gaseous fuel flow may continue for a short period after liquid fuel flow has begun. This system improves the life of the catalytic converter and the engine, reduces hydrocarbon and carbon monoxide emissions during starting and eliminates the need for special, higher cost, gasoline mixes for winter cold starting.

Brief description of the accompanying drawings
[0004] An embodiment of the invention is described with reference to the following accompanying drawings:
[0005] Fig. 1 depicts a high pressure fuel pump (100).
[0006] Fig 2 depicts a system (200) to fulfill the excess fuel requirement in a vehicle.

Detailed description of the drawings
[0007] Figure 1 depicts a high pressure fuel pump (100). The high pressure fuel pump comprises a plunger (101). The plunger (101) has an element (102) comprising gear teeth. The high pressure fuel pump further comprises a fuel control rod (103). The fuel control rod (103) has a first set gear teeth connected to gear teeth of the element (102). The fuel control rod (103) further comprises a second set of gear teeth (105). The high pressure fuel pump further comprises a push rod (106) adapted to interact with the second set of gear teeth (105). A spring (107) is mounted on the push rod (106) to keep the push rod (106) in position. The push rod (106) on actuation interacts with the second set of gear teeth (105).

[0008] In an embodiment of the invention mentioned above, in the high pressure fuel pump (100), instead of a push rod (106) a ring gear is used. The push rod (106) and the element (102) of the plunger (101) is connected to the teeth of the ring gear at diametrically opposite ends. In another embodiment of the high pressure fuel pump (100) mentioned above, instead of the fuel control rod (103) having two set of gear teeth a sleeve with gear teeth is mounted on the fuel control rod (103).

[0009] Figure 2 depicts a system (200) to fulfill the excess fuel requirement in a vehicle. The system (200) comprises at least two components, a high pressure fuel pump (100) and an actuator (108) placed on the dashboard of the vehicle. The high pressure fuel pump (100) comprises a plunger, a fuel control rod (103), a push rod (106) and at least a spring (107). The plunger (101) comprises an element (102) having a gear teeth. The fuel control rod (103) has a first set of gear teeth (104) connected to gear teeth of the element (102). A second set of gear teeth (105) is present on the fuel control rod (103). The push rod (106) is adapted to interact with the second set of gear teeth (105). A spring (107) mounted on the push rod (106) to keep the push rod (106) in position. The actuator (108) placed on the dashboard of the vehicle, is connected to the push rod (106). The push rod (106) on actuation by the actuator (108) placed on the dashboard of the vehicle interacts with the second set of gear teeth (105).

[0010] In an embodiment of the system (200) described above, instead of a push rod (106) a ring gear is used. The push rod (106) and the element (102) of the plunger (101) is connected to the teeth of the ring gear at diametrically opposite ends. In another embodiment of the system (200) mentioned above, instead of the fuel control rod (103) having two sets of gear teeth a sleeve with gear teeth is mounted on the fuel control rod (103).

[0011] In order to start the vehicle or achieve a minimum engine speed, it is required that an optimum amount of fuel enters the high pressure fuel pump (100) from the fuel tank along with a minimum threshold temperature of the fuel. In cold conditions to compensate for the temperature of the fuel, more quantity of fuel is required. Using the embodiments described in the present invention, this operation can now be done manually by the user of the vehicle by operating the actuator (108) on the dashboard of the vehicle.

[0012] When the actuator (108) on the on dash board of the vehicle is operated, it pushes the push rod (106) downward and it interacts with the fuel control rod (103). Now the user of vehicle can cause to and fro motion of the fuel control rod (103) by operating the actuator (108) on the dashboard of the vehicle. The to and fro motion of the fuel control rod (103) translates to a rotational movement of the element (102) of the plunger. The rotational movement of the plunger (101) controls the amount of fuel entering the fuel gallery of the fuel pump. Hence by operating the actuator (108) on the dashboard of the vehicle, the user of the vehicle can ultimately control the amount of fuel entering the fuel gallery of high pressure fuel pump (100). Once the operation of actuator (108) is over, the spring (107) mounted on the push rod (106) restores the push rod (106) to its original position.

[0013] In an embodiment of the present invention as described above, a ring gear is used instead of a fuel control rod (103) with two sets of gear teeth. The ring gear through its gear teeth connects to the element (102) of the plunger (101) and the push rod (106) at its diametrically opposite ends. The push rod (106) when actuated connects to the ring gear. By rotating the push rod (106), the element (102) connected on the other side of ring gear makes the plunger (101) rotate. Hence the rotational motion of the push rod (106) by the user of the vehicle translates to the rotational motion of the plunger, thereby varying the amount of fuel entering the fuel gallery of the fuel pump.

[0014] In another embodiment of the present invention as described above, instead of the fuel control rod (103) having two set of gear teeth a sleeve with gear teeth is mounted on the fuel control rod (103). The sleeve acts as a cover to the fuel control rod (103). The sleeve through its gear teeth connects to the element (102) of the plunger (101) and the push rod (106) at its diametrically opposite ends. The push rod (106) when actuated connects to the gear teeth of the sleeve. By rotating the push rod (106), the element (102) connected on the other side of gear teeth of the sleeve makes the plunger (101) rotate. Hence the rotational motion of the push rod (106) by the user of the vehicle translates to the rotational motion of the plunger (101), thereby varying the amount of fuel entering the fuel gallery of the fuel pump.

[0015] This idea to develop a high pressure fuel pump (100) helps in manually regulating the amount of fuel supplied in the plunger of the high pressure fuel pump. This is specifically useful in cold conditions, when more amount of fuel is required to start the engine. This design of high pressure fuel pump (100) can help eliminate startability issues in cold conditions.

[0016] It must be understood that the embodiments explained in the above detailed description are only illustrative and do not limit the scope of this invention. Any modification to this high pressure fuel pump (100) are envisaged and form a part of this invention. The scope of this invention is limited only by the claims.