Claims:STATEMENT OF CLAIMS
We claim:
1. A system (100) for controlling fuel flow to a dual fuel engine, said system (100) comprising:
a primary fuel control means (102);
at least one linkage (104), where one end of said linkage (104) is connected to said primary fuel control means (102) and another end of said linkage (104) is connected to a stop lever (L) of a fuel feed unit (F);
at least one locking element (106); and
at least one stopper (105) adapted to be connected onto said linkage (104),
wherein
said primary fuel control means (102) is adapted to move the stop lever (L) of the fuel feed unit (F) to at least a partly open position therein to regulate the primary fuel flow to the dual fuel engine on movement of said primary fuel control means (102); and
said locking element (106) is adapted to engage said stopper (105) to restrict a movement of said linkage (104) thereby maintaining the stop lever (L) at the partly open position.

2. The system (100) as claimed in claim 1, wherein said system (100) comprises a user interface unit adapted to provide information to a controller unit to operate the engine in at least one of a dual fuel mode and a primary fuel mode.

3. The system (100) as claimed in claim 2, wherein said system (100) comprises a sensor (110) adapted to be connected to said locking element (106),
wherein
said sensor (110) provides information about dual fuel mode to the controller unit to operate the engine in dual fuel mode on engagement of said locking element (106) with the stopper (105).

4. The system (100) as claimed in claim 3, wherein a secondary fuel is provided to the dual fuel engine by actuating at least one of at least one secondary fuel injector and at least one secondary fuel control valve through the controller unit to facilitate substitution of at least a portion of the primary fuel with corresponding amount of secondary fuel to the dual fuel engine based on the information from at least one of said user interface unit and said sensor (110).

5. The system (100) as claimed in claim 1, wherein said system (100) comprises a lock nut (108) adapted to secure said locking element (106) on a mounting member (M) therein to restrict a movement of said locking element (106), wherein the mounting member (M) is connected to a front scuttle of the vehicle.

6. The system (100) as claimed in claim 1, wherein said primary fuel control means (102) is adapted to be move the stop lever (L) to a closed position to restrict primary fuel flow to the dual fuel engine thereby switching off the engine on movement of said primary fuel control means (102).
7. The system (100) as claimed in claim 3, wherein the stop lever (L) is adapted to be moved to an open position to allow primary fuel flow to the engine on movement of said primary fuel control means (102) to its initial position in response to dis-engagement of said locking element (106) from said stopper (105); and
the controller unit is adapted to cut off secondary fuel flow to the engine based on the information about primary fuel mode from at least one of said sensor (110) and said user interface unit.

8. The system (100) as claimed in claim 2, wherein said primary fuel control means (102) is at least one of a handle and a hand operated knob;
said linkage (104) is at least a cable;
said stopper (105) is at least a nut;
said user interface unit is at least one of a switch, a lever, a knob, a button and a an application present on a user device, a user interface on vehicle infotainment system and a user interface on vehicle dashboard; and
said locking element (106) is at least one of a lever and a hand operated bracket.

9. A method (300) for controlling fuel flow to a dual fuel engine, said method (300) comprising:
moving a primary control means (102) which in turn moves a stop lever (L) of a fuel feed unit (F) to at least a partly open position to regulate primary fuel flow to the dual fuel engine;
maintaining the stop lever (L) at the partly open position by engaging a locking element (106) with a stopper (105) to restrict a movement of at least one linkage (104) which connects the stop lever (L) with the primary fuel control means (102);
providing information by, a sensor (110), about a dual fuel mode to a controller unit on engagement of the locking element (106) with the stopper (105); and
controlling secondary fuel flow to the dual fuel engine through the controller unit to facilitate substitution of at least a portion of the primary fuel with corresponding amount of secondary fuel to the dual fuel engine based on the information from at least one of the sensor (110) and a user interface unit.

10. The method (300) as claimed in claim 9, wherein said method (200) comprises,
moving the stop lever (L) to an open position to allow primary fuel flow to the engine on movement of the primary fuel control means (102) to its initial position in response to dis-engagement of the locking element (106) from the stopper (105); and
cutting off the secondary fuel flow to the engine through the controller unit thereby operating the engine in a primary fuel mode when at least one of the sensor (110) and the user interface unit provides information about the primary fuel mode to the controller unit.

11. A system (200) for controlling fuel flow to a dual fuel engine, said system (300) comprising:
an electric motor (202) adapted to be provided in communication with a controller unit (206);
a plurality of linkages (204F, 204S) adapted to couple said electric stepper motor (202) with a stop lever (R) of a fuel feed unit (M); and
a user interface unit (208) adapted to be provided in communication with the controller unit (206),
wherein
the controller unit is adapted to actuate said electric motor (202) which in turn moves the stop lever (R) to an open position to allow primary fuel flow to the dual fuel engine based on the information from said user interface unit (208).

12. The system (200) as claimed in claim 11, wherein the controller unit (206) is adapted to control secondary fuel flow to the engine when said electric motor (202) is being actuated by said user interface unit (208) through the controller unit (206).

13. The system (200) as claimed in claim 11, wherein the controller unit (206) is adapted to receive information about engine boost mode from a control means (208A) of said user interface unit (208); and
the controller unit (208) is adapted to actuate said electric motor (202) to allow primary fuel flow to the engine for a time period to generate desired power by the engine to at least one of restrict switching off of the engine and improve operability of a vehicle in agricultural fields.
14. The system (200) as claimed in claim 11, wherein the controller unit (206) is adapted to receive information about engine switch off mode from an engine switch off means (208B) of said user interface unit (208); and
the controller unit (206) is adapted to actuate said electric motor (202) which in turn moves the stop lever (R) of the fuel feed unit (M) to a closed position to restrict primary fuel flow to the engine thereby switching off the engine, where said electric motor (202) is at least an electric stepper motor.

15. The system (300) as claimed in claim 11, wherein said controller unit (206) is configured to:
receive information about at least one of operating speed of the engine and exhaust gas temperature of engine through an engine speed sensor (210) and an exhaust gas temperature sensor (212) respectively;
determine operating load of the engine based on the measured exhaust gas temperature;
actuate said electric motor (202) which in turn moves the stop lever (R) of the fuel feed unit (M) to a partly open position to regulate primary fuel flow to the engine; and
actuate at least one of at least one secondary fuel control valve and at least one secondary fuel injector to allow secondary fuel flow to the dual-fuel engine to facilitate substitution of at least a portion of the primary fuel with corresponding amount of secondary fuel flow to the dual-fuel engine based on at least one a part throttle operation, a full throttle operation, the operating load of the engine, and the operating speed of the engine.

16. A method (400) for controlling fuel flow to a dual fuel engine, said method (400) comprising:
actuating an electric motor (202) through a controller unit (206) based on an information about engine boost mode from a control means (208A) of a user interface unit (208);
moving by, the electric motor (202), a stop lever (R) of a fuel feed unit (M) to an open position to allow desired primary fuel flow to the engine for a time period to generate desired power by the engine to at least one of restrict switching off the engine and improve operability of a vehicle; and
controlling a secondary fuel flow to the engine through the controller unit (206) when the electric motor (202) is being actuated by the control means (208A) of the user interface unit (208) through the controller unit (206)

17. The method (400) as claimed in claim 16, wherein said method (400) comprises,
actuating the electric motor (202) through the controller unit (206), where the electric motor (202) is at least an electric stepper motor;
moving by, the electric motor (202), the stop lever (R) of the fuel feed unit (M) to a partly open position to regulate the primary fuel flow to the engine; and
controlling secondary fuel flow to the dual fuel engine through the controller unit (206) to facilitate substitution of at least a portion of the primary fuel with corresponding amount of secondary fuel to the dual fuel engine based on at least one of a part throttle operation, a full throttle operation in the vehicle, an operating speed of the engine and an operating load of the engine.

18. The method (400) as claimed in claim 16, wherein said method (400) comprises,
actuating the electric motor (202) through the controller unit (206) based on the information about engine switch off mode from an engine switch off means (208B) of the user interface unit (208); and
moving by, the electric motor (206), the stop lever (L) of the fuel feed unit (F) to a closed position to restrict primary fuel flow to the dual fuel engine thereby switching off the dual fuel engine.
, Description:TECHNICAL FIELD
[001] The embodiments herein relate to systems and methods for controlling fuel flow to a dual fuel engine.

BACKGROUND
[002] Dual fuel engine is a type of engine which combusts two types of fuels to reduce emissions and to improve operating economy. Usually, the dual fuel engine is a compression ignition (CI) engine which operates on a primary fuel and a secondary fuel. The primary fuel includes any of diesel, petro-diesel, bio-diesel and so on. The secondary fuel includes any of compressed natural gas (CNG), liquefied petroleum Gas (LPG) and so on. In the dual fuel engine, the diesel is injected directly into a combustion chamber and the CNG is inducted into an intake manifold with air or directly into engine cylinder. The inducted CNG results in reduction in the flow of diesel depending on the operating zone of the engine.
[003] The dual fuel engine is associated with a mechanical fuel injection pump which is used to control the diesel flow to the dual fuel engine. The position of the mechanical fuel injection pump lever is almost around same operating angle for a particular no load engine speed and for varying engine loads which in turn limits the flexibility in controlling diesel flow at different operating zones. Therefore, controlling the diesel flow from the mechanical fuel injection pump to the dual fuel engine is difficult and is one of the challenges posed to the original equipment manufacturers (OEM’S).
[004] Generally, fuel substitution rate is most important in dual fuel operation as this determines the operating economy which benefits the user gains when the dual fuel engine is running on dual fuel mode. It is difficult to interpret the CNG flow to the dual fuel engine based on the position of the fuel injection pump lever and engine speed. During full throttle operation and part throttle operation, diesel is provided to the dual fuel engine resulting in limited or zero CNG flow to the dual fuel engine which in turn creates a negative impact on total fuel consumption and emissions. For example, the diesel flow to the dual fuel engine remains same when the fuel injection pump lever is in full lock position (100% throttle) and substitution of diesel by CNG to the dual fuel engine is not possible in this operating zone which in turn reduces the overall operating efficiency.
[005] When tractors are operated in agricultural fields, there could be random speed drop or switching off of the engine due to the difference in the load acting on the engine due to field conditions or operating requirements affecting the operability of the vehicle.
[006] Therefore, there exists a need for systems and methods for controlling fuel flow to a dual fuel engine, which obviates the aforementioned drawbacks.

OBJECTS

[007] The principal object of embodiments herein is to provide systems for controlling fuel flow to a dual fuel engine.
[008] Another object of embodiments herein is to provide methods for controlling fuel flow to a dual fuel engine.
[009] Another object of embodiments herein is to provide fuel control systems in a vehicle, which achieves primary fuel substitution by reducing the excess primary fuel flow to an all speed governed dual-fuel engine and increasing secondary fuel flow to the dual-fuel engine and also reduces emissions during at least one of a part throttle operation and a full throttle operation in the vehicle and also based on operating load of the dual fuel engine.
[0010] Another object of embodiments herein is to provide systems for controlling fuel flow to a dual fuel engine, which has better primary fuel substitution rate thereby achieving fuel economy and reduced emissions and improves operating economy.
[0011] Another object of embodiments herein is to provide systems and methods for controlling fuel flow to a dual fuel engine based on requirement of user.
[0012] Another object of an embodiment herein is to provide systems for controlling primary fuel flow to an all speed governed dual fuel engine during a full throttle operation in a vehicle, which reduces emission, improves substitution of primary fuel, improves overall fuel economy and improves operating economy.
[0013] Another object of embodiments herein is to provide systems for controlling fuel flow to a dual fuel engine, which enables the dual fuel engine to produce desired power to restrict switching off of the engine and/or to improve operability of a vehicle.
[0014] Another object of embodiments herein is to provide systems for controlling primary fuel flow to a dual fuel engine for better substitution of at least a portion of a primary fuel with corresponding amount of a secondary fuel to the dual fuel engine during at least a part throttle operation in a vehicle and when the dual fuel engine is at a full load condition.
[0015] These and other objects of embodiments herein will be better appreciated and understood when considered in conjunction with following description and accompanying drawings. It should be understood, however, that the following descriptions, while indicating embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF DRAWINGS
[0016] The embodiments are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0017] Fig. 1 depicts a schematic view of a system for controlling fuel flow to a dual fuel engine, where the engine is being operated in a primary fuel mode, according to first embodiments as disclosed herein;
[0018] Fig. 2 depicts a schematic view of the system, where the engine is being operated in dual fuel mode, according to first embodiments as disclosed herein;
[0019] Fig. 3 depicts a schematic view of the system, where fuel flow to engine is cut off to switch off the engine, according to first embodiments as disclosed herein;
[0020] Fig. 4 depicts a flowchart indicating a method of controlling fuel flow to the dual fuel engine, according to first embodiments as disclosed herein;
[0021] Fig. 5 depicts a block diagram of a system for controlling fuel flow to a dual fuel engine, according to second embodiments as disclosed herein;
[0022] Fig. 6 depicts a perspective view of an electric stepper motor coupled to a stop lever of a fuel feed unit, according to second embodiments as disclosed herein; and
[0023] Fig. 7 depicts a flowchart indicating a method of controlling fuel flow to the dual fuel engine, according to second embodiments as disclosed herein.

DETAILED DESCRIPTION
[0024] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0025] The embodiments herein achieve systems and methods for controlling fuel flow to a dual fuel engine. Further, embodiments herein achieve a system for providing desired primary fuel flow to the dual fuel engine with control in secondary fuel flow thereof, which enables the engine to produce desired power to restrict switching off the engine and/or for better operability of the vehicle in agricultural fields. Referring now to the drawings Figs 1 through 7, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.
[0026] Fig. 1 depicts a schematic view of a system (100) for controlling fuel flow to a dual fuel engine, where the engine is being operated in a primary fuel mode, according to first embodiments as disclosed herein. In the first embodiment, the system (100) is adapted to control a primary fuel flow to the dual fuel engine for better substitution of at least a portion of the primary fuel with corresponding amount of a secondary fuel to the dual fuel engine based on requirement of user. In the first embodiment, the system (100) comprises a primary fuel control means (102), at least one linkage (104), at least one stopper (105), a locking element (106), a lock nut (108), a sensor (110) and a user interface unit (not shown). For the purpose of this description and ease of understanding, the system (100) is explained herein below with reference to controlling primary fuel flow to an all speed governed diesel engine for substitution of a portion of the primary fuel with corresponding amount of secondary fuel to the dual fuel engine present in an agricultural vehicle based on requirement of user. However, it is also within the scope of this invention to practice/ implement the system (100) to control primary fuel flow to any other type of dual fuel engine or multi fuel engine present in any of agricultural vehicle, off-road vehicle, any other type of vehicles and machines based on requirement of user without otherwise deterring the intended function of the system (100) as can be deduced from the description and corresponding drawings.
[0027] For the purpose of this description and ease of understanding, the primary fuel provided to the dual fuel engine is at least diesel and the secondary fuel provided to the dual fuel engine is at least compressed natural gas (CNG). However, it is also within the scope of the invention to provide any of petro-diesel, bio-diesel and other fuels as primary fuel and to provide any of liquefied petroleum gas (LPG) and other fuel as secondary fuel to the dual fuel engine without otherwise deterring the intended function of the system 100 for regulating primary and secondary fuel flow to the dual fuel engine as can be deduced from the description and corresponding drawings.
[0028] In the first embodiment, the primary fuel control means (102) is adapted to control the primary fuel flow to the dual fuel engine based on requirement of the user. For the purpose of this description and ease of understanding, the primary fuel control means (102) is considered to be at least one of a handle and a hand operated knob. However, it is also within the scope of this invention to provide any of levers or any other manual operated means for controlling the primary fuel flow to the dual fuel engine based on requirement of user without otherwise deterring the intended function of the primary fuel control means (102) as can be deduced from the description and corresponding drawings. The primary fuel control means (102) is adapted to be mounted onto a front scuttle (not shown) of the vehicle. However, it is also within the scope of this invention to mount the primary fuel control means (102) on any other components of vehicle with respect to the pull to stop linkage (cable) line without otherwise deterring the intended function of the primary fuel control means (102) as can be deduced from the description and corresponding drawings. The primary fuel control means (102) is connected to a stop lever (L) of a fuel feed unit (F), as shown in fig. 1) through the linkage (104). For the purpose of this description and ease of understanding, the fuel feed unit (F) is considered to be a fuel injection pump and the stop lever (L) is a pull to stop lever. The primary fuel control means (102), as shown in fig. 2) is moved by user and the primary fuel control means (102) in turn moves the stop lever (L) to a partly open position (as shown in fig. 2) therein to regulate the primary fuel flow to the dual fuel engine and a controller unit (not shown) is adapted to receive an information about dual fuel mode from at least one of the user interface unit (not shown) and the sensor (110) and accordingly the controller unit (not shown) is adapted to control the secondary fuel flow to the dual fuel engine by actuating at least one of at least one secondary fuel injector (not shown) and at least one secondary fuel control valve (not shown) to facilitate substitution of at least a portion of the primary fuel with corresponding amount of secondary fuel to the dual fuel engine. For example, the primary fuel control means (102) is adapted to move the stop lever (L) of the fuel feed unit (F) to the partly open position (as shown in fig. 2) to decrease the primary fuel flow to the engine and the controller unit is adapted to receive an information about dual fuel mode from at least one of the user interface unit (not shown) and the sensor (110) and accordingly the controller unit (not shown) is adapted to control the secondary fuel flow to the engine to substitute the decrease in amount of primary fuel to the engine. The partly open position of the stop lever (L) is defined as a half open position of the stop lever (L). The opening percentage of the stop lever (L) in the partly open position is 50 percentage. In another example, the partly open position of the stop lever (L) is defined as opening percentage of the stop lever (L) ranging between 25 percentage to 50 percentage.
[0029] The primary fuel control means (102) is adapted to be moved by the user and the primary fuel control means (102) in turn moves the stop lever (L), as shown in fig. 3) to a closed position to restrict primary fuel flow to the dual fuel engine thereby switching off the dual fuel engine. The stop lever (L) is adapted to be moved to an open position (as shown in fig. 1) to allow primary fuel flow to the engine on movement of the primary fuel control means (102) to its initial position in response to dis-engagement of the locking element (106) from the stopper (105) and the controller unit (not shown) is adapted to cut off secondary fuel flow to the engine based on the information about primary fuel mode from at least one of the sensor (110) and the user interface unit (not shown).
[0030] The controller unit (not shown) is configured to receive information about the dual fuel mode from at least one of the user interface unit (not shown) and the sensor (110) and accordingly the controller unit (not shown) is configured to actuate at least one of at least one secondary fuel control valve and at least one secondary fuel injector to allow secondary fuel flow to the dual-fuel engine to facilitate substitution of at least a portion of the primary fuel with corresponding amount of secondary fuel flow to the dual fuel engine.
[0031] In the first embodiment, the linkage (104) is adapted to connect the primary fuel control means (102) with the stop lever (L) of the fuel feed unit (F). One end (104f), as shown in fig. 1) of the linkage (104) is connected to the primary fuel control means (102) and another end (104s), as shown in fig. 1) of the linkage (104) is connected to the stop lever (L) of the fuel feed unit (F). For the purpose of this description and ease of understanding, the linkage (104) is considered to be a cable. However, it is also within the scope of this invention to provide any of rods, chains, ropes and other type of linkages for connecting the primary fuel control means (102) with the stop lever (L) of the fuel feed unit (F) without otherwise deterring the intended function of the linkage (104) as can be deduced from the description and corresponding drawings.
[0032] In the first embodiment, the stopper (105) is adapted to engage the locking element (106) to restrict a movement of the linkage (104) thereby maintaining the stop lever (L) in the partly open position when the engine is operated in dual fuel mode. For the purpose of this description and ease of understanding, the stopper (105) is considered to be a nut. However, it is also within the scope of this invention to provide any other means to restrict the movement of the linkage (104) without otherwise deterring the intended function of the stopper (105) as can be deduced from the description and corresponding drawings. The stopper (105) is provided on the linkage (104).
[0033] In the first embodiment, the locking element (106) is adapted to be moved to a locked position (as shown in fig. 2) in which the locking element (106) is engaged with the stopper (105) to restrict a movement of the linkage (104) thereby maintaining the stop lever (L) at the partly open position during the dual fuel mode. The locking element (106) is adapted to be moved to an unlocked position (as shown in fig. 1) in which the locking element (106) is dis-engaged from the stopper (105) to operate the dual fuel engine in primary fuel mode. The locking element (106) is adapted to engage the stopper (105) to restrict a movement of the linkage (106) thereby maintaining the stop lever (L) at the partly open position. The locking element (106) is movably connected to a mounting member (M), as shown in fig. 1), where the mounting member (M) is connected to the front scuttle (not shown) of the vehicle. For example, the locking element (106) defines an elongated slot (not shown) adapted to receive the mounting member (M) to mount the locking element (106) on the mounting member (M) and to facilitate vertical movement of the locking element (106) with respect to the mounting member (M) to engage the locking element (106) with the stopper (105) or to disengage the locking element (106) from the stopper (105). For the purpose of this description and ease of understanding, the locking element (106) is considered to be at least one a lever and a hand operated bracket. However, it is also within the scope of this invention to provide any other means for restricting the movement of the linkage (104) without otherwise deterring the intended function of the locking element (106) as can be deduced from the description and corresponding drawings. The locking element (106) defines a slot (not shown) provided at a bottom end of the locking element (106), where the slot (not shown) of the locking element (106) is adapted to receive a portion of the linkage (104) to engage the locking element (106) with the stopper (105) to restrict the movement of the linkage (104).
[0034] The lock nut (108) is adapted to secure the locking element (106) on the mounting member (M) to restrict the movement of the locking element (106). The sensor (110) is adapted to be connected to the locking element (106). The sensor (110) is provided in communication with the controller unit (not shown). The sensor (110) is adapted to indicate about at least one of the primary fuel mode and the dual fuel mode to the controller unit (not shown). The sensor (110) provides the information to the controller unit (not shown) to operate the engine in dual fuel mode when the locking element (106) engages the stopper (105). For example, the sensor (110) engages with the stopper (105) on engagement of the locking element (106) with the stopper (105) and accordingly the sensor (110) provides information about dual fuel mode to the controller unit (not shown) to operate the engine in the dual fuel mode. The sensor (110) dis-engages from the stopper (105) on dis-engagement of the locking element (106) from the stopper (105) and accordingly the sensor (110) provides information about primary fuel mode to the controller unit (not shown) to operate the engine in the primary fuel mode. For the purpose of this description and ease of understanding, the sensor (110) is considered to be a micro switch which is provided to the locking element (106). However, it is also within the scope of the invention to provide any other type of sensors for detecting the engagement or dis-engagement of the locking element (106) with respect to the stopper (105) to indicate the primary fuel mode or dual fuel mode to the controller unit (not shown).
[0035] The user interface unit (not shown) is adapted to be provided in communication with the controller unit (not shown). The user interface unit (not shown) is adapted to indicate the user defined inputs such as dual fuel mode or primary fuel mode to the controller unit therein to operate the engine in dual fuel mode or primary fuel mode. For the purpose of this description and ease of understanding, the user interface unit is considered to be a manual operated switch. However, it is also within the scope of the invention the user interface unit in form of any of levers, knobs, buttons and any other manual operated means without otherwise deterring the intended function of the user interface unit as can be deduced from the description and corresponding drawings. In another first embodiment, the user interface unit (not shown) is considered to be an application present on a user device (such as a mobile phone, a smart phone, a computer, a laptop, and so on), a user interface on the vehicle infotainment system, a user interface on the vehicle dashboard, and so on. The switch in an ON position is adapted to provide information about dual fuel mode to the controller unit (not shown) to operate the engine in the dual fuel mode. The switch in an OFF position is adapted to provide information about primary fuel mode to the controller unit to operate the engine in the primary fuel mode. The controller unit (not shown) continues to operate the engine in dual fuel mode even when the user interface unit indicate primary fuel mode to the controller unit (not shown) unless the sensor (110) indicate primary fuel mode to the controller unit (not shown). Similarly, the controller unit (not shown) continues to operate the engine in primary fuel mode even when the user interface unit indicate dual fuel mode to the controller unit (not shown) unless the sensor (110) indicate dual fuel mode to the controller unit (not shown).
[0036] Fig. 4 depicts a flowchart indicating a method (300) of controlling fuel flow to the dual fuel engine, according to first embodiments as disclosed herein. For the purpose of this description and ease of understanding, the method (300) is explained herein below with reference to controlling primary fuel flow to an all speed governed diesel engine for substitution of a portion of the primary fuel with corresponding amount of secondary fuel to the dual fuel engine present in an agricultural vehicle. However, it is also within the scope of this invention to practice/implement the entire steps of the method (300) in a same manner or in a different manner or with omission of at least one step to the method (300) or with any addition of at least one step to the method (300) for controlling primary fuel flow to any other type of dual fuel engine or multi fuel engine present in any of agricultural vehicle, off-road vehicle, any other type of vehicles and machines, where substitution of a portion of the primary fuel with corresponding amount of secondary fuel is required, without otherwise deterring the intended function of the method (300) as can be deduced from the description and corresponding drawings. In the first embodiment, the method (300) includes, moving a primary fuel control means (102) which in turn moves a stop lever (L) of a fuel feed unit (F) to at least a partly open position to regulate primary fuel flow to the dual fuel engine, step (302), maintaining the stop lever (L) at the partly open position by engaging a locking element (106) with a stopper (105) to restrict a movement of the at least one linkage (104) which connects the stop lever (L) with the primary fuel control means (102), step (304), providing information by, a sensor (110), about a dual fuel mode to a controller unit on engagement of the locking element (106) with the stopper (105), step (306) and controlling secondary fuel flow to the dual fuel engine by actuating at least one of at least one secondary fuel injector and at least one secondary fuel control valve through the controller unit to facilitate substitution of at least a portion of the primary fuel with corresponding amount of secondary fuel to the dual fuel engine based on the information from at least one of an user interface unit and the sensor (110), step (308).
[0037] The method (300) includes moving the primary fuel control means (102) which in turn moves the stop lever (L) of the fuel feed unit (F) to a closed position to restrict primary fuel flow to the dual fuel engine thereby switching off the dual fuel engine.
[0038] The method (300) includes moving the stop lever (L) to an open position (fully open position) to allow primary fuel flow to the engine on movement of the primary fuel control means (102) to its initial position in response to dis-engagement of the locking element (106) from the stopper (105) and cutting off the secondary fuel flow to the engine through the controller unit thereby operating the engine in a primary fuel mode when at least one of the sensor (110) and the user interface unit provides information about the primary fuel mode to the controller unit.
[0039] The method (300) includes, providing by, the user interface unit, information about the dual fuel mode to the controller unit step (301) prior to the method step (302) of moving the primary fuel control means (102) to move the stop lever (L) of the fuel feed unit (F) to at least the partly open position to regulate primary fuel flow to the dual fuel engine.
[0040] Fig. 5 depicts a block diagram of a system (200) for controlling fuel flow to a dual fuel engine, according to second embodiments as disclosed herein. In the second embodiment, the system (200) is adapted to provide desired primary fuel flow to the dual fuel engine and controls secondary fuel flow to the dual fuel engine for a time period to generate desired power by the dual fuel engine to restrict switching off of the dual fuel engine when the vehicle is operated in agricultural fields and/or to improve operability of the vehicle in agricultural fields based on the requirement of the user. In the second embodiment, the system (200) is adapted to control the primary fuel flow to the dual fuel engine for better substitution of at least a portion of the primary fuel with corresponding amount of the secondary fuel to the dual fuel engine based on at least one of a part throttle operation, a full throttle operation in a vehicle, an operating load of the dual fuel engine and an operating speed of the engine. In the second embodiment, the system (200) includes an electric motor (202), a plurality of linkages (204F, 204S), a controller unit (206) and a user interface unit (208), an engine speed sensor (210), an exhaust gas temperature sensor (212) and a throttle position sensor (214). For the purpose of this description and ease of understanding, the system (200) is explained herein below with reference to providing desired primary fuel flow to an all speed governed dual fuel engine and controlling secondary fuel flow to the engine to restrict switching off of the engine and/or to improve operability of the vehicle, and also to controlling primary fuel flow to the all speed governed diesel engine for substitution of a portion of the primary fuel with corresponding amount of secondary fuel to the dual fuel engine present in an agricultural vehicle. However, it is also within the scope of this invention to practice/implement the system (200) for controlling fuel flow to any other type of dual fuel engine or multi fuel engine present in any of agricultural vehicle, off-road vehicle, any other type of vehicles and machines, where restricting of switching off of the engine and/or operability of the vehicle and substitution of a portion of the primary fuel with second fuel is required, without otherwise deterring the intended function of the system (200) as can be deduced from the description and corresponding drawings.
[0041] Fig. 6 depicts a perspective view of an electric motor (202) coupled to a stop lever (R) of a fuel feed unit (M), according to second embodiments as disclosed herein. For the purpose of this description and ease of understanding, the electric motor (202) is considered to be an electric stepper motor. However, it is also within the scope of this invention to provide any other type of electric motors without otherwise deterring the intended function of the electric motor (202) as can be deduced from the description and corresponding drawings. In the second embodiment, the electric motor (202) is adapted to control the primary fuel flow to the dual fuel engine. The electric motor (202) is coupled with the stop lever (R) of the fuel feed unit (M) through the plurality of linkages (204). For the purpose of this description and ease of understanding, the fuel feed unit (M) is considered to be a fuel injection pump. The electric motor (202) is adapted to move the stop lever (R) to an open position to allow desired primary fuel flow to the dual fuel engine for a time period to generate desired power by the engine to restrict switching off of the engine and/or to improve operability of the vehicle when the electric motor (202) is actuated by the controller unit (206) based on the information from a control means (208A), as shown in fig. 5) of the user interface unit (208), where controller unit controls the secondary fuel flow to the dual fuel engine when the electric motor (202) is actuated by the control means (208A) of the user interface unit (208) through the controller unit (206).
[0042] The electric motor (202) is adapted to be actuated by the controller unit (206) and the electric motor (202) is adapted to move the stop lever (R) to a partly open position therein to regulate the primary fuel flow to the dual fuel engine when the electric stepper motor (202) is actuated by the controller unit (206) and accordingly the controller unit (206) is adapted to control the secondary fuel flow to the dual fuel engine by actuating at least one of at least one secondary fuel injector (not shown) and at least one secondary fuel control valve (not shown) to facilitate substitution of at least a portion of the primary fuel with corresponding amount of secondary fuel to the dual fuel engine based on the part throttle operation, the full throttle operation in the vehicle, the operating speed of the engine and the operating load of the engine.
[0043] The electric motor (202) is adapted to move the stop lever (R), as shown in fig. 6) of the fuel feed unit (M) to a closed position to restrict primary fuel flow to the dual fuel engine thereby switching off the dual fuel engine when the electric motor (202) is actuated by the controller unit (206) based on the information from an engine switch off means (208B), as shown in fig.5) of the user interface unit (208).
[0044] It is also within the scope of the invention to provide any of hydraulic cylinders, pneumatic cylinders, electric motor with extendable and retractable shaft, an slidable mechanism, a ratchet and pinion gear mechanism, telescopic adjustable mechanism, an extendable and retractable mechanism, an adjustable screw mechanism, a linear adjustable actuators and a telescopic cylinder mechanism, in place of the electric motor (202) for moving the stop lever (R) of the fuel feed unit (M) to control primary fuel flow to the engine.
[0045] In the second embodiment, the plurality of linkages (204F, 204S) is adapted to couple the electric motor (202) with the stop lever (R) of the fuel feed unit (M). The plurality of linkages (204F, 204S) includes a first linkage (204F) and a second linkage (204S). One end of the first linkage (204F) is connected with a shaft (not shown) of the electric motor (202) and another end of the first linkage (204F) is connected to the second linkage (204S). One end of the second linkage (204S) is connected to the stop lever (R) of the fuel feed unit (M) and another end of the second linkage (204S) is connected to the first linkage (204F). For the purpose of this description and ease of understanding, the first linkage (204F) is considered to be a bracket and the second linkage (204S) is considered to be a rod. However, it is also within the scope of this invention to provide any of cables, ropes, chains and any other connecting means for coupling the electric motor (202) with the stop lever (R) of the fuel feed unit (M) without otherwise deterring the intended function of the linkages (204F, 204S) as can be deduced from the description and corresponding drawings.
[0046] The controller unit (206) is adapted to actuate the electric motor (202) which in turn moves the stop lever (R) to the partly open position therein to regulate the primary fuel flow to the dual engine and the controller unit (206) is adapted to control the secondary fuel flow to the dual fuel engine by actuating at least one of at least one secondary fuel injector (not shown) and at least one secondary fuel control valve (not shown) to facilitate substitution of at least a portion of the primary fuel with corresponding amount of secondary fuel to the dual fuel engine based on the part throttle operation, the full throttle operation in the vehicle, the operating speed of the engine and the operating load of the engine.
[0047] The controller unit (206) is adapted to receive information from the control means (208A) of the user interface unit (208) and accordingly the controller unit (206) actuates the electric motor (202) to move the stop lever (R) of the fuel feed unit (M) to the open position to allow desired primary fuel flow to the dual fuel engine for the time period to generate desired power by the engine to restrict switching off of the engine and/or to improve operability of the vehicle, where the controller unit (206) controls the secondary fuel flow to the dual fuel engine when the electric motor (202) is being actuated by the controller unit (206) based on the information about engine boost mode from the control means (208A) of the user interface unit (208).
[0048] The controller unit (206) is adapted to actuate the electric motor (202) which in turn moves the stop lever (R) of the fuel feed unit (M) to the closed position to restrict primary fuel flow to the dual fuel engine thereby switching off the dual fuel engine when the controller unit (206) receives information about engine switch off mode from the engine switch off means (208B) of the user interface unit (208).
[0049] The controller unit (206) is configured to receive information about at least one of operating speed of the engine and exhaust gas temperature of engine through the engine speed sensor (210) and the exhaust gas temperature sensor (212) respectively. The controller unit (206) is configured to determine operating load of the engine based on the measured exhaust gas temperature. However, it is also within the scope of this invention to determine the operating load of the engine by using any of any other operating parameters of the engine, any other type of sensors and methods associated thereof. The controller unit (206) is adapted to receive information about the throttle position through the throttle position sensor (214).
[0050] The user interface unit (208) is adapted to provide user defined inputs such as the engine boost mode and the engine switch off mode to the controller unit (206). In the engine boost mode, the controller unit (206) actuates the electric motor (202) to move the stop lever (R) of the fuel feed unit (M) to the open position to allow desired primary fuel flow to the dual fuel engine for the time period to generate desired power by the engine to restrict switching off of the engine and/or to improve operability of the vehicle in agricultural fields. In the engine switch off mode, the controller unit (206) is adapted to actuate the electric motor (202) which in turn moves the stop lever (R) of the fuel feed unit (M) to the closed position to restrict primary fuel flow to the dual fuel engine thereby switching off the dual fuel engine. The user interface unit (208) includes a control means (208A) and an engine switch off means (208B), as shown in fig. 5). For the purpose of this description and ease of understanding, the control means (208A) and the engine switch off means (208B) of the user interface unit (208) are considered to be manual operated switches. However, it is also within the scope of the invention to consider the control means (208A) and the engine switch off means (208B) of the user interface unit (208) as any of levers, knobs, buttons and any other manual operated means without otherwise deterring the intended function of the control means (208A) and engine switch off means (208B) of the user interface unit (208) as can be deduced from the description and corresponding drawings. In another second embodiment, the user interface unit (208) is considered to be an application present on a user device (such as a mobile phone, a smart phone, a computer, a laptop, and so on), a user interface on the vehicle infotainment system, a user interface on the vehicle dashboard, and so on. The control means (208A) is a switch when moved to an ON position provides information about the engine boost mode to the controller unit (206). For example, the control means (208A) is switched ON for 30 to 60 seconds to allow primary fuel flow to the dual fuel engine to generate desired power to restrict switching off of the engine and/or to improve operability of the vehicle. The engine switch off means (208B) is a switch when moved to an ON position provides information about the engine switch off mode to the controller unit (206).
[0051] The engine speed sensor (210) is adapted to detect the operating speed of the engine and accordingly the engine speed sensor (210) provides the information to the controller unit (206). The exhaust gas temperature sensor (212) is adapted to detect the exhaust gas temperature and accordingly the exhaust gas temperature sensor (212) provides the information to the controller unit (206). The throttle position sensor (214) is adapted to detect the throttle position of at least one of a hand operated throttle means (not shown) and a foot operated throttle means (not shown) and accordingly the throttle position sensor (214) provides the information to the controller unit (206).
[0052] Fig. 7 depicts a flowchart indicating a method (400) of controlling fuel flow to the dual fuel engine, according to the second embodiment as disclosed herein. For the purpose of this description and ease of understanding, the method (400) is explained herein below with reference to providing desired primary fuel flow to an all speed governed dual fuel engine and controlling secondary fuel flow to the engine to restrict switching off of engine and to improve operability of the vehicle based on the requirement of user and to controlling primary fuel flow to the all speed governed diesel engine for substitution of a portion of the primary fuel with corresponding amount of secondary fuel to the dual fuel engine present in an agricultural vehicle. However, it is also within the scope of this invention to practice/implement the entire steps of the method (400) in a same manner or in a different manner or with omission of at least one step to the method (400) or with any addition of at least one step to the method (400) for controlling fuel flow to any other type of dual fuel engine or multi fuel engine present in any of agricultural vehicle, off-road vehicle, any other type of vehicles and machines, where substitution of a portion of the primary fuel with corresponding amount of secondary fuel and also restricting switching off of the engine and to improve operability of the vehicle is required, without otherwise deterring the intended function of the method (400) as can be deduced from the description and corresponding drawings. In an embodiment, the method (400) includes, actuating an electric motor (202) through a controller unit (206) based on the information about engine boost mode from a control means (208A) of the user interface unit (208), step (402), moving by, the electric motor (202), a stop lever (R) of a fuel feed unit (M) to an open position to allow desired primary fuel flow to the engine for a time period to generate desired power by the engine to restrict switching off of the engine and/or to improve operability of the vehicle in agricultural fields, step (404) and controlling a secondary fuel flow to the engine through the controller unit (206) when the electric motor (202) is being actuated by the controller unit (206) based on the information from the control means (208A) of the user interface unit (208), step (406).
[0053] The method (400) includes, actuating the electric motor (202) through the controller unit (206) and moving by, the electric stepper motor (202), the stop lever (R) of the fuel feed unit (M) to a partly open position to regulate the primary fuel flow to the engine and controlling secondary fuel flow to the dual fuel engine by actuating at least one of at least one secondary fuel injector and at least one secondary fuel control valve through the controller unit (206) to facilitate substitution of at least a portion of the primary fuel with corresponding amount of secondary fuel to the dual fuel engine based on at least one of the part throttle operation, the full throttle operation in the vehicle, the operating speed of the engine and operating load of the engine.
[0054] The method (400) includes, receiving, by the controller unit (206), the information about at least one of operating speed of the engine and exhaust gas temperature of engine through an engine speed sensor (210) and an engine exhaust temperature sensor (212) respectively.
[0055] The method (400) includes, actuating the electric motor (202) through the controller unit (206) based on the information about engine switch off mode from an engine switch off means (208B) of the user interface unit (208) and moving by, the electric motor (206), the stop lever (L) of the fuel feed unit (F) to a closed position to restrict primary fuel flow to the dual fuel engine thereby switching off the dual fuel engine.
[0056] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modifications within the spirit and scope of the embodiments as described herein.