Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
183 words
A method of operating a fuel system supplying metered quantities of fuel for delivery to an internal combustion engine, said system having a cyclically operable fuel pump, a metering means to receive fuel supplied by the pump, and a processor to control the metering means to deliver a metered quantity of fuel to the engine, said processor determining the metered quantity of fuel required by the engine in response to signal inputs thereto indicating engine operating conditions, said method including intermittently operating said pump under control of the processor to maintain a fuel supply to the metering means at a pressure between selected limits, said limits being selected so that the pump delivers during each period of operation a quantity of fuel greater than a multiple of the maximum single metered quantity of fuel deliverable by the metering means, sensing the pressure of the fuel supply to the metering means, and inputting to the processor a signal indicative of the sensed pressure, said processor applying said fuel pressure signal in the control of the metering means to deliver the required quantity of fuel.
Claim 2
Independent Claim
183 words
A method of operating a fuel system supplying metered quantities of fuel for delivery to an internal combustion engine, said system having a cyclically operable fuel pump, a metering means to receive fuel supplied by the pump, and a processor to control the metering means to deliver a metered quantity of fuel to the engine, said processor determining the metered quantity of fuel required by the engine in response to signal inputs thereto indicating engine operating conditions, said method including intermittently operating said pump under control of the processor to maintain a fuel supply to the metering means at a pressure between selected limits, said limits being selected so that the pump delivers during each period of operation a quantity of fuel greater than a multiple of the maximum single metered quantity of fuel deliverable by the metering means, sensing the pressure of the fuel supply to the metering means, and inputting to the processor a signal indicative of the sensed pressure, said processor applying said fuel pressure signal in the control of the metering means to deliver the required quantity of fuel.
Claim 3
Dependent Claim
39 words
A method of operating a fuel system as claimed in claim 1 wherein the processor also applies said fuel pressure signal in the control of the intermittent operation of the pump to maintain the fuel pressure within said limits.
Claim 4
Dependent Claim
22 words
A method of operating a fuel system as claimed in claim 2, wherein the fuel pump delivers the fuel to an accumulator.
Claim 5
Dependent Claim
44 words
A method of operating a fuel system as claimed in claim 1 wherein the fuel pump delivers fuel to an accumulator, and the intermittent operation of the pump is controlled in response to predetermined variations in the pressure of the fuel in the accumulator.
Claim 6
Dependent Claim
50 words
A method of operating a fuel system as claimed in claim 4 including sensing the pressure of the fuel in the accumulator, and inputting to the processor a signal indicative of said sensed fuel pressure, said processor applying said signal in the control of the intermittent operation of the pump.
Claim 7
Dependent Claim
50 words
A method of operating a fuel system as claimed in claim 1 wherein the metering means delivers the metered quantity of fuel into a gas charge, and said sensing of the pressure of the fuel is determined by reference to the pressure differential between the fuel and said gas charge.
Claim 8
Independent Claim
227 words
A method of operating a fuel system supplying metered quantities of fuel for delivery to an internal combustion engine, said system having a cyclically operable fuel pump, a metering means to receive fuel supplied by the pump and a processor to control the metering means to deliver a metered quantity of fuel into a gas charge delivered to the engine, said processor determining the metered quantity of fuel required by the engine in response to signal inputs thereto indicating engine operating conditions, said method including intermittently operating said pump under control of the processor to maintain a fuel supply to the metering means at a pressure between selected limits, said limits being selected so that the pump delivers during each period of operation a quantity of fuel greater than a multiple of the maximum single metered quantity of fuel deliverable by the metering means, sensing the pressure of the fuel supply to the metering means by reference to a pressure differential between the fuel and said gas charge, inputting to the processor a signal indicative of the sensed pressure, said processor applying said fuel pressure signal in the control of the metering means to deliver the required quantity of fuel, and controlling the pressure of the gas charge by said processor to vary said gas charge pressure in response to predetermined changes in engine load and/or speed.
Claim 9
Independent Claim
227 words
A method of operating a fuel system supplying metered quantities of fuel for delivery to an internal combustion engine, said system having a cyclically operable fuel pump, a metering means to receive fuel supplied by the pump and a processor to control the metering means to deliver a metered quantity of fuel into a gas charge delivered to the engine, said processor determining the metered quantity of fuel required by the engine in response to signal inputs thereto indicating engine operating conditions, said method including intermittently operating said pump under control of the processor to maintain a fuel supply to the metering means at a pressure between selected limits, said limits being selected so that the pump delivers during each period of operation a quantity of fuel greater than a multiple of the maximum single metered quantity of fuel deliverable by the metering means, sensing the pressure of the fuel supply to the metering means by reference to a pressure differential between the fuel and said gas charge, inputting to the processor a signal indicative of the sensed pressure, said processor applying said fuel pressure signal in the control of the metering means to deliver the required quantity of fuel, and controlling the pressure of the gas charge by said processor to vary said gas charge pressure in response to predetermined changes in engine load and/or speed.
Claim 10
Dependent Claim
25 words
A method as claimed in claim 7 wherein the processor increases the gas charge pressure when the engine fuel requirement is above a predetermined level.
Claim 11
Dependent Claim
125 words
A fuel system for an internal combustion engine, said system comprising a fuel pump for delivering fuel from a fuel reservoir to a fuel metering means, including an intermediate reservoir downstream of the fuel pump and located between the fuel pump and the fuel metering means, sensor means to generate a signal indicative of the pressure of the fuel in the intermediate reservoir, and a processor to receive and process said signal to maintain said pressure of the fuel in the intermediate reservoir within predetermined limits by selectively and intermittently switching the fuel pump on and off to deliver during each period of operation a quantity of fuel greater than a multiple of the maximum single metered quantity of fuel deliverable by the metering means.
Claim 12
Dependent Claim
125 words
A fuel system for an internal combustion engine, said system comprising a fuel pump for delivering fuel from a fuel reservoir to a fuel metering means, including an intermediate reservoir downstream of the fuel pump and located between the fuel pump and the fuel metering means, sensor means to generate a signal indicative of the pressure of the fuel in the intermediate reservoir, and a processor to receive and process said signal to maintain said pressure of the fuel in the intermediate reservoir within predetermined limits by selectively and intermittently switching the fuel pump on and off to deliver during each period of operation a quantity of fuel greater than a multiple of the maximum single metered quantity of fuel deliverable by the metering means.
Claim 13
Dependent Claim
100 words
A fuel system for an internal combustion engine, said system comprising a fuel pump for delivering fuel from a fuel reservoir to a fuel rail in communication with a fuel metering means, including an intermediate reservoir downstream of the fuel pump and located between the fuel pump and said fuel rail, sensor means to generate a signal indicative of the pressure of the fuel in the intermediate reservoir, and a processor to receive and process said signal to maintain said pressure of the fuel in the intermediate reservoir within predetermined limits by selectively switching the fuel pump on and off.
Claim 14
Dependent Claim
100 words
A fuel system for an internal combustion engine, said system comprising a fuel pump for delivering fuel from a fuel reservoir to a fuel rail in communication with a fuel metering means, including an intermediate reservoir downstream of the fuel pump and located between the fuel pump and said fuel rail, sensor means to generate a signal indicative of the pressure of the fuel in the intermediate reservoir, and a processor to receive and process said signal to maintain said pressure of the fuel in the intermediate reservoir within predetermined limits by selectively switching the fuel pump on and off.
Claim 15
Dependent Claim
28 words
The method of operating a fuel system as claimed in claim 3, wherein fuel passes through an accumulator located between the fuel pump and the fuel metering means.
Claim 16
Dependent Claim
33 words
The method of operating a fuel system as claimed in claim 3, wherein fuel passes through an accumulator located between the fuel pump and a fuel rail in communication with said metering means.
Claim 17
Dependent Claim
43 words
The method of operating a fuel system as claimed in claim 3 wherein the accumulator stores during each period of pump operation said quantity of fuel greater than a multiple of the maximum single metered quantity of fuel deliverable by the metering means.
Claim 18
Dependent Claim
114 words
A fuel system for an internal combustion engine, said system comprising a fuel pump for delivering fuel from a fuel reservoir to a fuel metering means, including an intermediate reservoir downstream of the fuel pump, sensor means to generate a signal indicative of the pressure of the fuel in the intermediate reservoir, and a processor to receive and process said signal to maintain said pressure of the fuel in the intermediate reservoir within predetermined limits by selectively and intermittently switching the fuel pump on and off to deliver during each period of operation a quantity of fuel greater than a multiple of the maximum single metered quantity of fuel deliverable by the metering means.
Claim 19
Dependent Claim
114 words
A fuel system for an internal combustion engine, said system comprising a fuel pump for delivering fuel from a fuel reservoir to a fuel metering means, including an intermediate reservoir downstream of the fuel pump, sensor means to generate a signal indicative of the pressure of the fuel in the intermediate reservoir, and a processor to receive and process said signal to maintain said pressure of the fuel in the intermediate reservoir within predetermined limits by selectively and intermittently switching the fuel pump on and off to deliver during each period of operation a quantity of fuel greater than a multiple of the maximum single metered quantity of fuel deliverable by the metering means.
Claim 20
Dependent Claim
48 words
A fuel system as claimed in claim 9 wherein the processor is arranged to process said signal indicative of the pressure of the fuel in the intermediate reservoir in the control of the fuel metering means to deliver the quantity of fuel to meet the engine fuel demand.
Claim 21
Dependent Claim
41 words
The fuel system as claimed in claim 14 wherein the intermediate reservoir stores during each period of pump operation a quantity of fuel greater than a multiple of a maximum single metered quantity of fuel deliverable by the fuel metering means.
Claim 22
Dependent Claim
44 words
A method of operating a fuel system as claimed in claim 1, wherein the fuel pump delivers fuel to an accumulator, and the intermittent operation of the pump is controlled in response to predetermined variations in the level of the fuel in the accumulator.
Claim 23
Dependent Claim
50 words
A method of operating a fuel system as claimed in claim 17 including sensing the level of the fuel in the accumulator, and inputting to the processor a signal indicative of the sensed fuel level, said processor applying said signal in the control of the intermittent operation of the pump.