Fuel injection and control system

Claim 3

A system as recited in claim 1 wherein said means for varying the pressure of the application of fuel by said means for applying fuel under pressure does not reduce the pressure of said fuel below a predetermined minimum value.

Claim 4

A system as recited in claim 1 wherein there is included transducer means for establishing a first signal responsive to the square of mass air flow to said internal combustion engine which signal represents a desired fuel pressure, transducer means for establishing a second signal responsive to fuel pressure applied to said fuel injection valve which signal represents actual fuel pressure, means to which said first and second signals are applied for establishing a third signal respresentative of the square root of the ratio of said first and second signals, and means for reducing each interval over which said fuel injection valve is maintained open to an amount proportional to the amplitude of said third signal.

Claim 5

A system as recited in claim 1 wherein said means for applying fuel under pressure to said fuel injection valve from said source includes a first passageway between said source of fuel and said fuel injection valve, pump means for applying fuel under pressure from said source to said first passageway, and a second passageway communicating with and extending from said first passageway toward said source of fuel; said means for varying the pressure of the application of fuel includes a controllable spill valve coupling to said second passageway with said source of fuel.

Claim 6

A system as recited in claim 1 wherein said means for opening said fuel injection valve for a time varies inversely with the speed of said engine includes: means for generating a time signal having an amplitude proportional to the time required for said engine to rotate through a predetermined crank angle, transducer means for establishing a first signal responsive to the square of mass air flow to said internal combustion engine which signal represents a desired fuel pressure, transducer means for establishing a second signal responsive to fuel pressure applied to said fuel injection valve which signal represents actual fuel pressure, means to which said first and second signals are applied for establishing a third signal having an amplitude representative of the square root of the ratio of said first and second signals, means for reducing the amplitude of said time signal by said third signal amplitude, a ramp voltage generator, means responsive to said engine attaining a predetermined point in a cycle of its operation for generating a valve opening signal and for initiating operation of said ramp voltage generator, comparator means for comparing the output of said ramp voltage generator with said reduced time signal and producing a valve closing signal when they are equal, and means for applying said valve opening signal and thereafter said valve closing signal to said fuel injector valve causing it to open and then close in response thereto.

Claim 7

A system as recited in claim 1 wherein said means for opening said fuel injection valve for a time which varies inversely with the speed of said engine includes a source of a hydraulic fluid under pressure, means for applying hydraulic fluid under pressure from said source to said fuel injection valve to maintain said fuel injection valve upon the crankshaft of said engine attaining a first predetermined position in its cycle of operation, means for relieving the Pressure of said hydraulic fluid applied to said fuel injection valve when said engine attains a second predetermined position in its cycle of operation.

Claim 8

A system as recited in claim 6 wherein said means for applying hydraulic fluid under pressure from said source to said fuel injection valve to maintain said valve open upon the crankshaft of said engine attaining a first predetermined position in its cycle of operation includes: a housing having walls surrounding a central cavity therein, a ported shaft rotatably supported within said central cavity, means for rotatably driving said ported shaft from said engine, a first passageway extending through said housing walls to said ported shaft, means coupling said valve to said first passageway on the outside opening of said housing, an axial passageway in said ported shaft extending from said source of fluid under pressure part way through said ported shaft, and a radial passageway extending from said axial passageway in said ported shaft to communicate with said first passageway for every cycle of rotation of said ported shaft to enable application of fluid under pressure to said hydraulic fuel injection valve.

Claim 9

A system as recited in claim 7 wherein said means for relieving the pressure of said hydraulic fluid applied to said fuel injection valve when said engine attains a second predetermined position in its cycle of operation comprises: a sleeve rotatably supported on said ported shaft within said central cavity; a first pressure relief passageway extending through said housing walls to said source; a second pressure relief passageway in said ported shaft having one end extending to communicate with said first pressure relief passageway; a groove in the outer periphery of said sleeve extending for a predetermined distance along a circumference of said sleeve; a fourth pressure relief passageway extending from one end of said groove radially through said sleeve to communicate with the other end of said second pressure relief passageway in said ported shaft at least once during rotation of said ported shaft; a fifth pressure relief passageway coupling said first passageway extending through said housing walls to said groove in said sleeve periphery; motor means for moving said sleeve over an arc defined by said radial groove to position said fourth passageway in said sleeve at a desired location along the rotational path of said second relief passageway in said ported shaft; and means for controlling said motor means.

Claim 10

A system as recited in claim 8 wherein said means for controlling said motor means includes: transducer means for establishing a first signal responsive to the square of the mass air flow to said internal combustion engine which signal represents a desired fuel pressure; transducer means for establishing a second signal responsive to fuel pressure applied to said fuel injection valve which signal represents actual fuel pressure; means to which said first and second signals are applied for establishing a third signal representative of the square root of the ratio of said first and second signals; and means for operating said motor responsive to said third signal to position the opening of said fifth pressure relief passageway at said groove a distance from the other end thereof which is proportional to the amplitude of said third signal.

Claim 11

In a system for introducing fuel into the piston chamber of an internal combustion engine of the type which rotates a crank shaft, wherein there is a fuel injection valve for ach piston chamber, and the fuel injection valves are supplied with fuel under pressure from a common passageway, the improvement comprising means for opening each fuel injection valve over an interval required for said engine to operate through a predetermined crank shaft angle including, means for establishing for each cycle of rotation of said crank shaft a first timing signal hAving an amplitude representative of the maximum desirable open interval of said fuel injection valves for the speed at which said engine is then operating; means for successively opening each fuel injection valve at a predetermined point in the cycle of operation of said crank shaft; means for generating for each opened fuel injection valve a second timing signal whose amplitude starts from an initial value less than said first timing signal and increases in amplitude with the passage of time; means for comparing the amplitude of said first timing signal with the amplitude of each of said second timing signals and producing a fuel injection valve closing signal when they are equal, and means for modifying said interval by an amount determined by the square root of the ratio of the square of the mass air flow to said internal combustion engine and the pressure of the fuel being supplied to the common passageway.

Claim 12

In a system for introducing fuel into the piston chamber of an internal combustion engine of the type which rotates a crank shaft, wherein there is a fuel injection valve for ach piston chamber, and the fuel injection valves are supplied with fuel under pressure from a common passageway, the improvement comprising means for opening each fuel injection valve over an interval required for said engine to operate through a predetermined crank shaft angle including, means for establishing for each cycle of rotation of said crank shaft a first timing signal hAving an amplitude representative of the maximum desirable open interval of said fuel injection valves for the speed at which said engine is then operating; means for successively opening each fuel injection valve at a predetermined point in the cycle of operation of said crank shaft; means for generating for each opened fuel injection valve a second timing signal whose amplitude starts from an initial value less than said first timing signal and increases in amplitude with the passage of time; means for comparing the amplitude of said first timing signal with the amplitude of each of said second timing signals and producing a fuel injection valve closing signal when they are equal, and means for modifying said interval by an amount determined by the square root of the ratio of the square of the mass air flow to said internal combustion engine and the pressure of the fuel being supplied to the common passageway.

Claim 13

In a system as recited in claim 10 wherein said means for modifying said interval by an amount determined by the square root of the ratio of the square of the mass air flow to said internal combustion engine and the pressure of the fuel being supplied to the common passageway includes: means establishing a venturi passageway in the air intake passageway to said engine; first transducer means responsive to the air flow through said venturi passageway for generating a first electrical signal responsive to the air flow therethrough; second transducer means responsive to the pressure of the fuel in said common passageway for generating a second electrical signal; means to which said first and second electrical signals are applied for generating a third signal representative of the ratio thereof; means responsive to said third signal for generating a fourth signal representative of the square root thereof; and means for reducing said first timing signal amplitude by the amplitude of said fourth signal.

Claim 14

In a system as recited in claim 11 wherein there is included a fourth transducer means responsive to the air flow through the air intake passageway downstream of said venturi passageway for establishing a fifth electrical signal representative thereof; and means for determining which is the larger of said fifth signal and said second signal; and means for applying the fifth signal to said means to which said first and second signals are applied in place of said second signal when it is the larger.

Claim 15

In a system for controlling the amount of fuel introduced into the piston chambers of an internal combustion engine by fuel injection valves which are supplied fuel under pressure from a common rail having one end connected to a fuel pump and the other end to a spill valve, fuel passing through the spill valve being collected in a reservoir said pump pumping fuel from said reservoir; said spill valve being controlled by the differential air pressure applied to a diaphragm between a venturi passageway formed in the air intake passageway for said engine and a location in said air intake passageway preceding said venturi passageway; the improvement comprising means for opening each fuel injection valve over an interval required for said engine to rotate its crank shaft through a predetermined crank shaft angle; and means for modifying said interval over which each fuel injection valve is open by an amount determined by the square root of the ratio of the square of the mass air flow through said venturi passageway and the pressure of fuel being applied to said fuel injection valves including a first transducer coupled to said venturi passageway for generating a first signal representative of the mass air flow therethrough; a second transducer coupled to said spill valve for generating a second signal representing actual fuel pressure; a third transducer coupled to said air intake passageway downstream of said venturi passageway for measuring idling air flow pressure and producing a Third signal representative thereof; comparator means to which said second and third signals are applied for producing an output which is the larger of the two; ratio means to which said comparator means output and said first signal is applied for producing an output which is the ratio of its inputs; square root means to which said ratio means output is applied for producing an output which is the square root of its input; and means responsive to the output of said square root means for modifying the interval over which each fuel injection valve is opened.

Claim 16

In a system for controlling the amount of fuel introduced into the piston chambers of an internal combustion engine by fuel injection valves which are supplied fuel under pressure from a common rail having one end connected to a fuel pump and the other end to a spill valve, fuel passing through the spill valve being collected in a reservoir said pump pumping fuel from said reservoir; said spill valve being controlled by the differential air pressure applied to a diaphragm between a venturi passageway formed in the air intake passageway for said engine and a location in said air intake passageway preceding said venturi passageway; the improvement comprising means for opening each fuel injection valve over an interval required for said engine to rotate its crank shaft through a predetermined crank shaft angle; and means for modifying said interval over which each fuel injection valve is open by an amount determined by the square root of the ratio of the square of the mass air flow through said venturi passageway and the pressure of fuel being applied to said fuel injection valves including a first transducer coupled to said venturi passageway for generating a first signal representative of the mass air flow therethrough; a second transducer coupled to said spill valve for generating a second signal representing actual fuel pressure; a third transducer coupled to said air intake passageway downstream of said venturi passageway for measuring idling air flow pressure and producing a Third signal representative thereof; comparator means to which said second and third signals are applied for producing an output which is the larger of the two; ratio means to which said comparator means output and said first signal is applied for producing an output which is the ratio of its inputs; square root means to which said ratio means output is applied for producing an output which is the square root of its input; and means responsive to the output of said square root means for modifying the interval over which each fuel injection valve is opened.

Claim 17

In a system as recited in claim 13 wherein there is included a choke valve in the engine air intake passageway positioned between said venturi passageway and the location in said air intake passageway which is used to establish differential pressure for said spill valve whereby upon starting said engine when said choke is closed said spill valve will be principally controlled by the air pressure at said location.

Claim 20

A system as recited in claim 15 wherein said means for controlling said spill valve includes means for controlling said spill valve for enabling a predetermined minimum fuel pressure to be applied to said fuel injection valves.

Claim 21

A system as recited in claim 16 wherein said means proportional to the mass air flow to said engine includes a first transducer for generating a first signal representative thereof, and said system includes a second transducer for sensing the pressure of fuel in said common rail and producing a second signal representative thereof, computer means to which said first and second signals are applied for determining an interval over which said fuel injection valves should remain open, and producing an output representative thereof, means responsive to said computer means output for accordingly modifying the interval over which each said fuel injection valve remains open.