DESC:[FIELD OF INVENTION]
[0001] The present subject matter relates to a fuel injection system of a vehicle. More particularly, the present invention relates to an electronically controlled fuel injection system of a vehicle by an ECU for a gaseous fuel.
[BACKGROUND OF THE INVENTION]
[0002] The conventional vehicles running on fossil fuels, emit a lot of pollutants and in turn pollute the environment. The curtailing of vehicle pollutants in the atmosphere can be achieved using alternate technology for reducing the emission of vehicle pollutants. To meet the need of the environmental concerns, instead of fuels made from fossils, gaseous fuel such as CNG and LPG were introduced for vehicle operation. In the conventional vehicle running on gaseous fuel, a throttle valve system is provided to control the air flow to the engine, wherein the gaseous fuel is supplied to an engine through mechanical pressure. To control the fuel into the engine, components like fuel injector, a control unit, a mechanical gas pressure regulator system, a gas cylinder is used. In such a system fuel injector supplies required amount of gaseous fuel to engine from the mechanical gas pressure regulator at a desired pressure. The mechanical pressure regulator system has a diaphragm and spring linkage mechanism to reduce and control the pressure which works based on various force balances.
[BRIEF DESCRIPTION OF DRAWING]
[0003] The detailed description is described with reference to the accompanying figures. The same numbers are used throughout the drawings with reference to the features and components.
[0004] Figure 1 (a) and Figure 1(b) represents a block diagram of the electrically controlled fuel injection system as per present invention.
[0005] Figure 2 presents a flowchart of inlet operation of the fuel injection system as per present invention.
[0006] Figure 3 presents a flowchart of for safety operation of the fuel injection system as per present invention.

[DETAILED DESCRIPTION OF THE INVENTION]
[0007] In a conventional engine running on gaseous fuel like LPG or CNG, a gas pressure reducer is used to reduce the high amount of pressure from the gas cylinder to be transferred to the engine. In ignition engine running with gaseous fuel which has a throttle valve system to control the air flow to the engine, gaseous fuel is supplied to the engine by using a mechanical pressure regulator system through a venture type mixer body arrangement. However, it is difficult to control the fuel supplied to the engine in a precise manner with a throttle valve system which results in engine inefficiency and higher emission. Also, such a system is complex requiring multiple mechanical components.
[0008] In a conventional gaseous fuel vehicle, there is a first reduction stage, where a high-pressure gas from the gas cylinder at 200 bar is reduced to a gas of 6 bar-8 bar. Furthermore, in the second reduction stage, this gas at 6 bar-8 bar pressure is further reduced to 1.5 bar using two processes which necessitates use of complicated mechanical structure involving diaphragms and levers which makes a system bulky and costly thereby requiring more cost for maintenance and manufacturing. With the advent of LPG technology, the first reduction stage got eliminated and the gas pressure reduction is being carried out through a mechanical gas pressure reduction system directly from a high-pressure gas of 6 bar-8 bar to 1.5 bar. Though this system is less complicated than earlier system, the use of a mechanical gas pressure reduction system makes it prone to damage and inaccurate pressure compression. In general, a high-pressure gas of 6 bar-8 bar is supplied from the cylinder to an inlet valve of the mechanical gas pressure reducer. This high-pressure gas is then passed to a diaphragm through a lever which also opens and closes the inlet valve. The high-pressure gas fills up an enclosed volume and a spring-like mechanism moves up the lever to compress the high-pressure gas in the enclosed volume. Once a force balance is achieved between the diaphragm and the enclosed volume, the inlet valve is closed and the compression of the high-pressure gas happens at 1.5 bar. However, the design of the lever and the diaphragm is complicated. Additionally, it is a challenge to keep the construction of the lever straight throughout its life of operation. Furthermore, dust particles can accumulate of the lever and the lever can also be affected by environmental conditions which damages its strength. This further leads to inaccurate compression of gaseous fuel over the period of time which in turn affects the functioning, performance and durability of the engine.
[0009] Additionally, for an LPG fuel-based system, the first stage of pressure reduction is not required because the LPG gas pressure pre-exists at required minimum pressure of 6 bar-8 bar. However, for a CNG fuel-based system, both the first stage and the second stage of pressure reduction are required because the CNG gas pressure pre-exists at a very high pressure for example around 200 bar and it must be reduced to 6 bar-8 bar by the first stage and this pressure is further reduced to 1.5 bar through the second stage for vehicle operation. Thus, a mechanical gas pressure reducer system requires multiple components for each stage and thereby increases the risk of failure of the system.
[00010] Hence, there is a need for a system which can efficiently control the pressure of the fuel in the fuel injection system using gaseous fuel, in simple, cost effective manner and efficient manner overcoming all problem cited above and other problems of known art.
[00011] Therefore it is an object of the present invention to provide a vehicle having an electronically controlled fuel injection system which can regulate the pressure of the gaseous fuel, hereinafter referred as fuel without any mechanical pressure reducer in a simple, cost effective, and efficient manner, increase serviceability. It is yet another object of the present invention to ensure safety of the electronically controlled fuel injection system when the pressure of the fuel is beyond a safety limit, so as to ensure no damage is caused to the sensors and other electronically controlled fuel injection system components.
[00012] As per an aspect of present invention, a vehicle is disclosed which comprises of a fuel container, an electronically controlled fuel injection system receiving fuel from the fuel container, an engine configured of receiving fuel from the a gaseous fuel injection system; and an ECU which is configured of monitoring the inlet and outlet of the electronically controlled fuel injection system based upon fuel property i.e., pressure of the fuel which is contained in the electronically controlled fuel injection system.
[00013] As per an aspect of the present invention, the electronically controlled fuel injection system, hereinafter called as ‘system’ comprises of a chamber which is adapted or configured to containing fuel by receiving from the fuel container for passing to an engine. The system also comprises of electrical inlet solenoid and an electrical outlet solenoid capable of injecting fuel into the chamber and passing fuel out of the chamber respectively. Additionally, the system is configured with a sensor which is capable of sensing pressure of fuel inside the chamber, a safety member for safety operation of the system, and a drain which can drain out the excess residue oil from the chamber.
[00014] As per yet another aspect of the present invention, a method of inlet operation of the system involves the flowing of fuel from the fuel container to the chamber, a sensor sensing the pressure of the fuel inside the chamber and sending the signal to the ECU. If the pressure of the fuel is more than a predetermined pressure value, then the electrical inlet solenoid is deactivated such that no more fuel is passed to the chamber of the system. However, if the pressure of the fuel is less than the predetermined pressure value, then the electrical inlet solenoid remains activated so that fuel from fuel container can be injected to the chamber.
[00015] As per yet another aspect of the present invention, a method of safety operation of the system involves the estimation of pressure i.e. first predetermined attribute of the fuel in the chamber. The first predetermined attribute is monitored by the controller, in case the first predetermined attribute is more than a predetermined safety limit then the safety member is activated. The activation of the safety member releases the fuel out of the chamber.
[00016] The present invention advantageously eliminates the use of mechanical pressure detector with an electronically actuated valve with a control volume system to regulate the gas pressure for achieving appropriate pressure of the fuel for supplying to the power unit i.e. engine. The present invention improves serviceability by eliminating mechanical parts and adding drain, eliminates the impact of environment such as rain and dirt on the mechanical part, improves safety requirements.
[00017] The present subject matter is further described with reference to accompanying figures. It should be noted that the description and figures merely illustrate the principles of the present subject matter. Various arrangements may be devised that, although not explicitly described or shown herein, encompass the principles of the present subject matter. Moreover, all statements herein reciting principles, aspects, and examples of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof.
[00018] The foregoing disclosure is not intended to limit the present disclosure to the precise forms or particular fields of use disclosed. As such, it is contemplated that various alternate embodiments and/or modifications to the present disclosure, whether explicitly described or implied herein, are possible in light of the disclosure. Having thus described embodiments of the present disclosure, a person of ordinary skill in the art will recognize that changes may be made in form and detail without departing from the scope of the present disclosure.
[00019] In the foregoing specification, the disclosure has been described with reference to specific embodiments. However, as one skilled in the art will appreciate, various embodiments disclosed herein can be modified or otherwise implemented in various other ways without departing from the spirit and scope of the disclosure. Accordingly, this description is to be considered as illustrative and is for the purpose of teaching those skilled in the art the manner of making and using various embodiments of the disclosure. It is to be understood that the forms of the disclosure herein shown and described are to be taken as representative embodiments. Equivalent elements, materials, processes or steps may be substituted for those representatively illustrated and described herein. Moreover, certain features of the disclosure may be utilized independently of the use of other features, all as would be apparent to one skilled in the art after having the benefit of this description of the disclosure. Expressions such as “including”, “comprising”, “incorporating”, “consisting of”, “have”, “is” used to describe and claim the present disclosure are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural.
[00020] Further, various embodiments disclosed herein are to be taken in the illustrative and explanatory sense, and should in no way be construed as limiting of the present disclosure. All joinder references (e.g., attached, affixed, coupled, connected, etc.) are only used to aid the reader's understanding of the present disclosure, and may not create limitations, particularly as to the position, orientation, or use of the systems and/or methods disclosed herein. Therefore, joinder references, if any, are to be construed broadly. Moreover, such joinder references do not necessarily infer that two elements are directly connected to each other.
[00021] Additionally, all numerical terms, such as, but not limited to, “first”, “second”, “third”, “primary”, “secondary”, “main” or any other ordinary and/or numerical terms, should also be taken only as identifiers, to assist the reader's understanding of the various elements, embodiments, variations and/or modifications of the present disclosure, and may not create any limitations, particularly as to the order, or preference, of any element, embodiment, variation and/or modification relative to, or over, another element, embodiment, variation and/or modification.
[00022] It will also be appreciated that one or more of the elements depicted in the drawings/figures can also be implemented in a more separated or integrated manner, or even removed or rendered as inoperable in certain cases, as is useful in accordance with a particular application. Additionally, any signal hatches in the drawings/figures should be considered only as exemplary, and not limiting, unless otherwise specifically specified.
[00023] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
[00024] Figure 1 (a) illustrates a block diagram of the electrically controlled fuel injection system as per present invention. Figure 1 (b) illustrates the block diagram of the system along with other components of the vehicle. Both the figure 1 (a) and 1 (b) are explained together for comprehensive understanding. An electronic fuel injection system (111) comprises a chamber (103) to which an electronically controlled inlet solenoid (104) and an electronically controlled outlet solenoid (106) is connected. The electronically controlled inlet solenoid (104) being configured to actuate opening and closing mechanism for supplying fuel into the chamber from a fuel container (100). The said electronic fuel injection system (111) further comprises a sensor (105) which is configured to be connected to the chamber (103). The sensor (105) determines the pressure of the fuel inside the chamber (103), i.e. first predetermined attribute of the fuel and then further monitoring of the first predetermined attribute of the fuel by a control unit i.e. an ECU to check if the value is within the pre-determined fuel pressure value.
[00025] The electronically controlled outlet solenoid (106) is further connected to the power unit (109). The electronically controlled outlet solenoid (106) is configured to be connected in any position between the chamber (103) and the power unit (109). The chamber (103) is further connected to a safety member (107). The safety member (107) is operated when there is an excess pressure inside the chamber (103) and this excess gas pressure is let out from the safety member (107).
[00026] The safety member (107) is further configured to be electronically operable. A drain plug (108) is configured to be connected at one end of the chamber (103). The drain plug (108) is configured to remove any contaminants and also the excess oil and soot collected in the chamber (103) due to the deposition and enclosure of high-pressure gases into the chamber (103). The drain plug (108) is primarily used for overhauling and servicing purposes. The system (111) is configured to be connected electronically with all the other elements in the vehicle.
[00027] In Figure 1 (b) a fuel cylinder (100) is configured to store gaseous fuel like LPG or CNG and the fuel cylinder (100) gives an output of a fuel pressured at desired range for vehicle operation such as 6 bar-8 bar. The pressured fuel at 6 bar-8 bar is supplied to a filter (110) which filters the fuel and further supplies this pressured fuel at 6 bar-8 bar to the electronically controlled inlet solenoid (104). The said electronically controlled inlet solenoid (104) opens and closes to allow the pressured fuel to be collected inside the chamber (103), only when the said electronically controlled inlet solenoid (104) receives a signal from the controller (101). The pressured fuel inside the chamber (103) is continuously monitored by the sensor (105), and the sensor (105) continuously sends the pressure and temperature data of the pressured fuel to the control unit (101). The pressured fuel at 6 bar-8 bar is then reduced to a low pressure gas at 1.5 bar inside the chamber (103) and when the sensor (105) senses this low pressure gas, the sensor (105) sends a signal to the controller (101). The controller (101) further sends a signal to the electrical outlet solenoid (106) to inject low- pressure gas fuel to the power unit (109) for the combustion to take place. Under the circumstances, that the electrical inlet solenoid (104) is unable to receive a signal from the controller (101) or is damaged, the safety member (107) is activated by the control unit (101) to release the extra pressured fuel out of the chamber (103) to prevent harm to the system as a whole (111).
[00028] Figure 2 illustrates a flowchart of inlet operation of the system (111). When a pressured gas at 6 bar-8 bar is flowed (step 201) through the electrical inlet solenoid (104) to the chamber (103), the pressure of fuel is continuously monitored to be at desired pressure for example at 1.5 bar by the sensor (105) and sends (step 202) the estimated pressure value to the control unit (101). If the control unit (101), determines (step 203) that the pressure inside the chamber (103) has reduced below the pre-determined desired limit for example below 1.5 bar, the control unit (101) sends a signal (step 205) to the electrical inlet solenoid (104) to open and let in adequate amount of high-pressured gas inside the chamber (103). In another condition, if the sensor (105) senses and sends (step 202) a signal to the control unit (101), and the control unit (101) determines (step 203) that the pressure inside the chamber (103) is greater than predetermined desired pressure for example 1.5 bar, the control unit (101) sends (step 204) a signal to the electrical inlet solenoid (104) to close and prevents further entry of the pressured fuel inside the volume enclosed chamber (103). Thus, the controller (111) continuously monitors the pressure inside the chamber (103) at desired pressure value. Thus, this mechanism can be adopted for any fuel system and the pre-determined pressure of the gas can be modulated based on the requirements of the fuel system with only one sensor thereby making it simple and cost effective.
[00029] Figure 3 illustrates a safety operation of the system as per present invention. A fail-safe mechanism to prevent damage to the system (111) has been adopted. The safety member (107) is operated either manually through a signal being given to an instrument cluster to open the safety member (107) or the safety member (107) is operable electronically by receiving a signal from the control unit (101). Under the circumstances, the electrical inlet solenoid (104) remains open due to system failure or due to inadequate sensing of the sensor (105), a large amount of gaseous fuel is collected inside the chamber (103). If the extra fuel is not drained immediately, it can damage the other components such as electrical outlet solenoid (106) or it can even damage the periphery walls of the chamber (103). Thus, in order to avoid this, the fuel is exited from the safety member (107). At first the pressure inside the chamber (103) is calculated (301) by the sensor (105). The calculated pressure at step (step 301) is transmitted (step 302) to the control unit (101). The control unit (101) if determines (step 303) that the pressure inside the chamber (103) is greater than a pre-determined value, the control unit (101) sends a signal to the safety member (107) to open or get activated (at step 304) for discarding and let excess pressured gas outside the chamber (103) to the environment or in a separate chamber. In other words, activating (step 304) the safety member (107) till the predetermined safety limit is achieved, Once this excess pressured fuel is let out from the chamber (103), the safety member (107) sends a signal to the control unit (101), and the control unit (101) sends a signal to close the operation of the safety member (107) and the normal mechanism of pressure reduction through electrical inlet solenoid (2) is continued. Else, if the calculated pressure in step (301) is less than the safety limit which is determined (step 303) by the control unit (101) then the pressure is again checked in cycle.
[00030] Many other improvements and modifications may be incorporated herein without deviating from the scope of the invention.

List of references:
100: Fuel container
101: Control unit
103: Chamber
104: Electrical inlet solenoid
105: Sensor
106: Electrical outlet solenoid
107: Safety member
108: Drain plug
109: Power unit
110: Filter
111: Electronically controlled fuel injection system
201-205: Flowchart of inlet operation of the system
301-304: Flowchart of safety operation of the system
,CLAIMS:We claim:
1. An electronically controlled fuel injection system (111) for a vehicle with gaseous fuel wherein said fuel injection system (111) comprising:
a chamber (103);
a fuel container (100) for supplying fuel to said chamber (103) ;
a power unit (109) configured to receive fuel from the chamber (103);
and a control unit (101) configured for monitoring first predetermined attribute of the fuel in said chamber (103) and controlling flow of fuel into said chamber (103), said fuel flow being through an inlet and an outlet of said chamber (103).
2. The system as claimed in claim 1, wherein said electronically controlled fuel injection system (111) comprises of:
said chamber (103) being configured for receiving fuel from said fuel container (100);
an electrical inlet solenoid (104) capable of injecting fuel into said chamber (103);
an electrical outlet solenoid (106) capable of passing fuel out of said chamber (103);
a sensor (105) capable of sensing said first predetermined attribute of fuel inside said chamber (103);
a safety member (107) for safe operation of said system (111) and a drain plug (108).
3. The system as claimed in claim 2, wherein a control unit (101) monitors said inlet and said outlet of said electronically controlled fuel injection system (111) based upon said first predetermined attribute of said fuel contained in said chamber (103).
4. The system as claimed in claim 2, wherein said drain plug (108) being configured for discarding a residue of said fuel from said chamber (103), said residue being formed by combustion of said fuel.
5. The system as claimed in claim 1, wherein a filter (110) being configured for filtering said fuel supplied to said inlet of said chamber (103), said filter (110) being disposed between said fuel container (100) and said electronically controlled fuel injection system (111).

6. A method of operation of an electronically controlled fuel injection system (111), wherein said method comprises steps of :
sensing (step 201) a first predetermined attribute of the fuel in a chamber (103) by a sensor (105);
sending (step 202) said first determined attribute at step 201 to an ECU (101);
monitoring (step 203) first predetermined attribute of said fuel in said chamber (103) by said ECU (101) :
deactivating (step 204) an electrical inlet solenoid (104) when said first predetermined attribute being more than a predetermined value;
activating (step 205) said electrical inlet solenoid (104) when said first predetermined attribute being less than a predetermined value.
7. The method of operation of the electronically controlled fuel injection system (111) as claimed in claim 6, said method comprising steps of:
supplying fuel (step 201) into a chamber (103) by a fuel container (100) for supplying fuel input to a power unit (109) through an inlet solenoid (104);
sending (step 202) information of a first attribute of said fuel inside said chamber (103) to an ECU (101), said first attribute being sensed by a sensor (105)
monitoring (step 203) by an Electronic Control Unit ECU (101), whether a first predetermined attribute of said fuel in said chamber (103) being greater than a predetermined value;
turning OFF of said inlet solenoid (104) by said ECU (101) on said determination being positive,
tuning ON of said inlet solenoid valve (104) by said ECU (101) on said determination being negative.
8. A method of safe operation of an electronically controlled fuel injection system (111) comprising the steps of:
sensing (step 301) a first predetermined attribute of a fuel in a chamber (103);
sending (step 302) information of said first attribute of said fuel to an EC (101), said first attribute being sensed by a sensor (105);
monitoring (step 303) by an ECU (101) the first predetermined attribute of said fuel in said chamber (103);
activating (step 304) a safety member (107) when said first predetermined attribute being more than a predetermined safety limit wherein said safety member (107) being active till predetermined safety limit being achieved.
9. A controller (101) of an electronically controlled fuel injection system (111) for a vehicle with gaseous fuel wherein said fuel injection system (111) being configured to monitor a flow of fuel in a chamber (103) for powering of a power unit (109), said monitoring being based on a first predetermined attribute sensed by an sensor (105).
10. The controller (101) of an electronically controlled fuel injection system (111) as claimed in claim 10, wherein the controller (101) monitors said first predetermined attribute of said fuel in said chamber (103) based on inputs from said sensor (105) and thereby controlling operation of an electrical inlet solenoid (104), an electrical outlet solenoid (106) and a safety member (107).
11. The controller (101) of an electronically controlled fuel injection system (111) as claimed in claim 10, wherein said controller (101) being configured to monitor a safe operation of said electronically controlled fuel injection system; monitoring said first predetermined attribute of said fuel in the chamber (103) and activating a safety member (107) when said first predetermined attribute being more than a predetermined safety limit, wherein said safety member (107) being activated till predetermined safety limit is achieved.