Abstract: A gaseous fuel control system for engines for delivering and regulating fuel and air flows to the engine and an electronically controlled rotary pressure regulator implementing fine adjustments in the pre-mixing pressure of gaseous fuel. Gaseous fuel from a high-pressure fuel tank is forced into a passage and through a series of pressure regulators during combustion. Inside a throttle body, butterfly plates respond to signals from an electronic controller to regulate the flows of air and gaseous fuel. The fuel passes into a stagnation chamber and mixes with the air flow through a series of radial mixing orifices in a common wall between the stagnation chamber and air passageways. The fuel/air ratio is coarsely controlled by the reaction of the butterfly plates to the signals of the electronic controller and is more finely controlled by electronic rotation of the rotary gas pressure regulator.

Abstract: To provide an injection system for an internal combustion engine operating on self-igniting liquefied gas as a fuel, and to minimize cavitation and related problems of fuel delivery as well as wear, the fuel tank is configured as a low-pressure storage tank which is connected to a pressure control unit that includes a fuel pumping unit for drawing fuel from the storage tank and delivering the fuel to the suction line of the fuel delivery device and a pressure release line which branches off the suction line and leads back to the storage tank, the pressure release line including a release valve for maintaining a constant interior pressure in the suction line above the vapor pressure of the liquefied gas. The injection system is configured as a leakage-free system.

Abstract: The internal combustion engine fuel system described includes a structure for mixing the alternative fuel, preferably hydrogen, with oxygen in ambient air to stratify the fuel. The system includes an adapter, and the adapter includes a housing mounted between spark plug and cylinder of the internal combustion engine. A plug is placed within the housing. The plug has ridges or grooves on its outer surface that act as mixing structures. Thus, when hydrogen is introduced into the adapter housing it is mixed with ambient oxygen within the chamber as it flows over the plug. The mixing structures in the housing create a vortexing action as the hydrogen flows over the plug and towards the cylinder of the engine. An electrode protrudes from the plug towards the cylinder. The electrode is preferably platinum and generates the necessary spark to create combustion of the hydrogen/air mixture adjacent to the cylinder to thereby power the cylinder in the engine.

Abstract: The invention relates to an apparatus and method for supplying high pressure gaseous fuel from a storage vessel to a vehicle's internal combustion engine. More particularly, the invention is a fuel supply system with three main components: the storage vessel; an intensifier; and, an accumulator vessel. Fuel passages connect each one of the components directly with the other two components. The intensifier has a plurality of compression chambers and one of the compression chambers can be by-passed when the intensifier is operating in a low capacity mode, depending upon the pressure in the storage vessel. The intensifier operates continuously. When no fuel compression is required, the intensifier runs in an idle mode with the respective inlets and outlets of the compression chambers connected by fuel passages, thus preventing any fuel compression. The loading to the intensifier actuating mechanism is balanced in all modes of operation.

Abstract: A fuel management system for a gaseous fuel internal combustion engine is disclosed in which a mass air flow sensor as well as a mass gas flow sensor provide input signals to an electronic control unit (ECU) which then determines the air/fuel ratio. The ECU in turn generates output signals to a fuel valve to control the mass of fuel flow to the engine and thus the air/fuel ratio. A turbocharger bypass valve, a precooler for the gaseous fuel supply, a pressure accumulator upstream from the fuel valve, as well as a system to calibrate the engine to the specific gaseous fuel is described to enhance the accuracy of the fuel management system. An improved pressure balanced valve for controlling the fuel flow to the engine is also provided as well as a cylinder pressure transducer to optionally provide an output signal to the ECU to determine the air/fuel ratio.

Abstract: A method and apparatus for supplying a gaseous fuel to a combustion engine is described. A required fuel flow is calculated, an actual fuel flow is measured, and a fuel flow control signal is adapted if a difference between the required and actual fuel flow is detected. The fuel flow may be measured using a differential pressure measurement. The fuel flow control signal and associated actual fuel flow may be stored in a continuously updated memory. The apparatus includes a pulse width modulation valve arranged in a fuel line, a fuel flow measurement assembly arranged downstream of the valve, and a device for generating a control signal for the valve. The control signal generating device is supplied with feedback from the flow measurement assembly and includes a continuously updated table for storing control signals and associated fuel flows.

Abstract: A fuel feed device for a gas engine includes a thermally insulated cartridge case for receiving therein a disposable gas cylinder or cartridge. The cartridge case has a built-in temperature sensor for detecting the temperature of the gas cartridge, and a built-in electric heater for heating the gas cartridge. The electric heater is controlled such that the temperature detected by the temperature sensor is kept within a predetermined temperature range. A working machine driven by the gas engine is also disclosed.

Abstract: A carburetor for low pressure gaseous fuel comprising: a hollow body having a through bore, a venturi in said through bore, a throttle valve downstream of said venturi, a jet positioned in the venturi, said jet connected to a gaseous fuel supply, a flow control valve interposed between said jet and said fuel supply, said control valve being operatively connected to the throttle valve such that movement of the throttle valve causes translation of a valve element in a gas port whereby the area of the port is varied to regulate the flow of gaseous fuel to the jet in direct proportion to movement of the throttle valve.

Abstract: A gaseous fuel filling structure includes a coupler connected to a gaseous fuel supply system, a gaseous fuel cylinder that stores a gaseous fuel at a high pressure, a fuel dissipation preventing device that prevents dissipation of the gaseous fuel, and a switching device that is selectively placed in a first state in which the coupler is connected to the gaseous fuel cylinder and disconnected from the fuel dissipation preventing device, or a second state in which the coupler is connected to the fuel dissipation preventing device. The switching device includes a member(s) for preventing back flow of the gaseous fuel from the gaseous fuel cylinder toward the coupler.

Abstract: A hydrogen and natural gas fuel mixture for internal combustion engines is provided for vehicle engines such as those used in standard production engines for automobiles, trains and lawn mowers. The gaseous fuel for operating a vehicle combustion engines includes approximately 21 to 50% Hydrogen and the rest natural gas constituents such as combinations of Methane, Carbon Dioxide, Nitrogen, Ethane, Propane, Iso-Butane, N-Butane, Iso Pentane, N-Pentane, and Hexanes Plus. A fuel mixture of approximately 28 to 36 percent Hydrogen and a air fuel equivalence ratio of approximately 0.625 is an extreme lean burn condition that yields hydrocarbon emission levels of less than approximately 104 ppm(0.84 hm/hp hr.). Current internal combustion engines that are in mass production can take this alternative fuel without any substantial modifications to their systems. This alternative fuel is lean burning and emits emissions that are below current legal standards.

Abstract: A fuel control unit which is formed in a housing such as a load block or carburetor has a passageway with a fuel inlet at one end thereof and a fuel outlet at the other end thereof. A pair of adjusting valves, one for adjusting the amount of fuel flow from a first fuel source such as natural gas and the other for adjusting the amount of fuel flow from a second fuel source such as propane are mounted in the passageway. The valves are positioned to set the sizes of metered passages and are preadjusted to provide the desired fuel flow to provide a proper air to fuel ratio for the fuel from each source. The passageway is alternatively set for proper operation with one or the other fuel sources either by manually positioning a shuttle valve or actuating a solenoid which drives the shuttle valve.

Abstract: Oil is burned controllably in an engine to reduce valve and valve guide wear and valve seat face recession, thus extending cylinder head and valve life. A nozzle discharges atomized oil into an intake manifold. The nozzle receives the oil from a pressurized source of oil. Used engine lubricating oil from the engine is preferably the source of oil, thus both disposing of used oil and allowing the lubricating oil to be maintained fresher. An atomizing fluid, such as air or natural gas, is fed to the nozzle for atomizing the oil. An air and fuel mixture conveys the atomized oil into combustion chambers where the oil is burned. The oil has an additive that leaves a finely dispersed ash residue in the combustion chambers when the oil is burned. Where a valve closes against a seat face in the cylinder head, the ash residue reduces valve wear and seat face recession, presumably because the ash residue provides a cushioning effect.

Abstract: A number of embodiments of gaseous fueled internal combustion engines in which the charge former has no throttle valve in it. A separate throttle body is provided downstream of the charge former in which the flow controlling throttle valve is positioned so as to protect the charge former from deposits being formed on its metering arrangements. In some embodiments the throttle body is disposed at an angle to the air passage through the charge former to provide further protection. By separating the charge former from the throttle body, the engine height can be kept low because the charge former can be positioned at any desired location. Both in-line and V-type arrangements are provided and with the V-type arrangement the charge former is disposed externally of the valley between the cylinder banks so as to further maintain a low hood line.

Abstract: A fuel measurement and control system for a gaseous fuel engine having a solenoid actuated fuel flow control valve which is electronically actuated to control a desired metering duration when the control system is operating in a fuel flow control mode. The fuel measurement and control system further includes mode control valve for switching the control system between a fuel flow control mode and a positive fuel shutoff mode, wherein the fuel flow control valve is prevented from opening when the control system is operating in a positive fuel shutoff mode. The fuel flow control valve includes a pressure balance chamber to balance the biasing forces acting on the valve from the gaseous fuel, wherein gaseous fuel is introduced into the pressure balancing chamber to provide the balancing forces.

Abstract: A compressed natural gas flow generating apparatus comprising: one or more gas supplies (62); a pressure controller (65) for controlling the pressure of gas injected by the gas supply (62); a fuel rail (68) for providing gas for the engine (20) from said pressure controller (65), the fuel rail (68) including a plurality of gas injectors (I1, I2, I3, I4) injecting gas and a plurality of gas injection tubes (23) coupled with the gas injectors (I1, I2, I3, I4), the gas injection tube (23) fixed to the inner wall (24a) of the intake port (24) of the cylinder head (30) by fixing means (40); a fuel supply line (80) for connecting the gas supply (62), the pressure controller (65) and the fuel rail (68); an electronic control unit (60) for outputting a control signal in order to inject a proper amount of the compressed natural gas into the engine (20) and electrically connected with the gas injectors (I1, I2, I3, I4), so that fast burning of the injected gas in the combustion chamber (22) is easily accomplished.

Abstract: A fuel injection method wherein optimum fuel injection timing in a fuel-injection type gas fuel engine is determined by setting fuel injection end timing to be after the start of opening of an intake valve. That is, when injection ends in a first half of the intake valve open period the volumetric efficiency .eta.v falls and the engine output also falls, because the injection period overlaps with a period of positive pressure arising inside the intake pipe before opening of the intake valve, but when injection ends in a second half of the intake valve open period the volumetric efficiency .eta.v rises and the engine efficiency also rises, because the injection period overlaps with a period of negative pressure arising in the intake pipe during the first half of the intake value open period. Consequently, when fuel is injected during this trough in the intake port pressure, the volumetric efficiency increases and the engine output also increases by several percent.

Abstract: A generator powered by an internal combustion engine is fueled from a source of biogas. The biogas flows through a filter which removes hydrogen sulfide and mercaptans and through a coalescer to remove water vapor. A regulator controls the biogas pressure supplied to the fuel intake of the engine carburetor, and acid-neutralizing oil is injected into the engine intake each time the engine is shut down to protect the engine from acidic constituents in the biogas.

Abstract: An internal combustion engine is provided with a cartridge containing a fuel/oil mixture where the fuel is liquid, normally gaseous fuel. The cartridges can be readily mounted or demounted from the engine, and provide flexibility of use coupled with easy starting. The use of the fuel/oil cartridges eliminates the need to separately mix oil and fuel, and eliminates substantial contact of the user with an oily fuel/oil mixture. The two cycle and four cycle cartridge-type engines are suitable for use in many hand-powered implements, including line trimmers, chain saws, leaf blowers, hedge trimmers, etc.

Abstract: A control system for and exhaust retarder in and exhaust pipe of an engine to which a mixer and throttle valve are connected including terminating means for terminating fuel feed into the engine upon receipt of an exhaust retarder shutter operation signal, an oxygen richness sensor on the exhaust pipe and a control system for operating an actuator for the exhaust retarder shutter when sensed oxygen density in the exhaust pipe deviates from a predetermined oxygen range.

Abstract: A system and method for selectively refueling a plurality of vehicle storage tanks with compressed natural gas (CNG) are provided that utilize a compressor system operable at suction pressures ranging from about 330 to about 3600 psig and discharge pressures ranging from about 330 to about 4500 psig in combination with means for temporarily storing CNG at an intermediate storage pressure of from about 330 to about 4500 psig, preferably from about 1700 to about 2700 psig, means for selectively filling vehicle storage tanks with CNG from an inlet source, from the compressor discharge and from the intermediate storage tanks, and means for selectively supplying CNG to the compressor inlet at either the available line pressure or the intermediate storage pressure.

Abstract: A method and apparatus for improving efficiency and reducing emissions of an internal combustion engine coupled to an inertial load. An apparatus is provided for controlling the energy exchange between engine and load so that the maximum conversion efficiency is obtained for both directions of energy flow. Valve controls make the engine a variable displacement expander or compressor so that kinetic energy received from the load by the engine may be stored as compressed air and returned to the load by the engine. These controls eliminate all fuel consumption and emissions when power is not required by the load, and utilize the stored energy in conventional engine operation.

Abstract: A fuel management system for a gaseous fuel internal combustion engine is disclosed in which a mass air flow sensor as well as a mass gas flow sensor provide input signals to an electronic control unit (ECU) which then determines the air/fuel ratio. The ECU in turn generates output signals to a fuel valve to control the mass of fuel flow to the engine and thus the air/fuel ratio. A turbocharger bypass valve, a precooler for the gaseous fuel supply, a pressure accumulator upstream from the fuel valve, as well as a system to calibrate the engine to the specific gaseous fuel is described to enhance the accuracy of the fuel management system. An improved pressure balanced valve for controlling the fuel flow to the engine is also provided as well as a cylinder pressure transducer to optionally provide an output signal to the ECU to determine the air/fuel ratio.

Abstract: The present invention is a system and method for oxidation of volatile organic compounds which is stored or held in a suitable storage structure such as an accumulation tank. The volatile organic compound stored in the accumulation tank is taken into the intake port of an operating internal combustion engine wherein the operating and internal combustion engine reduces the volatile organic compounds into carbon dioxide and water which appears in the exhaust gases of the operating engine.

Abstract: In order to increase the safety of an injection system in an internal combustion engine operating on self-igniting liquefied gas as a fuel, especially after the engine has been switched off, the proposal is put forward that at least one pressurized part of the injection system be depressurized by means of a shut-down device, the latter including at least one pressure relief line which is controlled by at least one valve and opens into a tank with a low pressure level.

Abstract: An improved, compact multiple barrel charge forming device for operating with gaseous fuels and which employs a single fuel chamber for supplying fuel to both barrels. A number of various manifolding arrangements are disclosed to facilitate application with multiple cylinder engines and, particularly, those having V arranged cylinder banks.

Abstract: An injection system for an internal combustion engine, in particular an engine operating on liquid gas as fuel or fuel component, includes an injection unit for each cylinder for direct fuel injection into the combustion chamber, and a fuel supply system with at least one fuel tank and an oscillating pump element configured as a displacer for delivery of the fuel. The pump element is provided with an elastic sealing element fitted in a housing and which divides a pump chamber into two subchambers sealed tightly against each other, the first subchamber being supplied with fuel via a fuel feed line of the fuel supply system, and the second subchamber being supplied with a secondary medium. The dead volumes of the pump element may be reduced by configuring the pump chamber as an annular chamber at least partially surrounding a shaft moving axially in a cylinder, which shaft is mechanically linked with the sealing element.

Abstract: A lawn mower which is powered by an engine that uses gaseous fuels, such as liquified petroleum gas (LPG), compressed natural gas (CNG) or liquified natural gas (LNG). It may be either built originally to use gaseous fuels, or it may be converted from using liquid hydrocarbon fuels such as gasoline or diesel fuel. It may also use a combination of gaseous and liquid hydrocarbon fuels. The lawn mower may be hand-pushed or be self-propelled. It may include a fuel injector having a cylindrical main body housing, a coupling connecting a fuel hose and the main body housing, a gaseous venturi retained within the main body housing, an air intake in the main body housing, a sleeve that can slide over the air intake, and a docking collar with a plurality of slots that fits over the main body housing.

Abstract: A gaseous fuel injection system for a cylinder of an internal combustion engine assures uniform mixing of the gaseous fuel with an air stream being inducted into the cylinder by injecting the gaseous fuel into the air stream at a relatively high velocity, preferably of between a Mach number of 0.5 and a Mach number of 1.0. High Mach injection can be achieved in a remarkably simple and effective manner by 1) using a single or at most a few injection conduit(s) and discharge orifice(s) for each intake port as opposed to a configuration having multiple discharge orifices at a single point in the air intake system upstream of the intake manifold, 2) by setting the relative effective flow areas of the injector metering orifice C.sub.d A1 and conduit discharge orifice C.sub.d A2 such that C.sub.d A2 is between 2 and 5 times greater than C.sub.d A1, and by 3) setting the gas supply pressure to be more than four times the air intake manifold absolute pressure.

Abstract: An internal combustion engine (14) having a fuel supply system (10) for supplying propane vapor to the intake system of the engine. Multi-point fuel injectors (30) are located at each cylinder (12) for primary delivery of the propane vapor. In addition, an engine controller (36) activates supply orifices (34), when needed, to supplement the amount of propane vapor delivered by the fuel injectors (30).

Abstract: A hydrogen and natural gas fuel mixture for internal combustion engines is provided for vehicle engines such as those used in standard production engines for automobiles, trains and lawn mowers. The gaseous fuel for operating a vehicle combustion engines includes approximately 21 to 50% Hydrogen and the rest natural gas constituents such as combinations of Methane, Carbon Dioxide, Nitrogen, Ethane, Propane, Iso-Butane, N-Butane, Iso Pentane, N-Pentane, and Hexanes Plus. A fuel mixture of approximately 28 to 36 percent Hydrogen and a air fuel equivalence ratio of approximately 0.625 is an extreme lean burn condition that yields hydrocarbon emission levels of less than approximately 104 ppm (0.84 hm/hp hr.). Current internal combustion engines that are in mass production can take this alternative fuel without any substantial modifications to their systems. This alternative fuel is lean burning and emits emissions that are below current legal standards.

Abstract: Method and device for regulating the NO.sub.x emission of an internal combustion engine. It has been found that the NO.sub.x emission is dependent on the efficiency of the engine. That is to say the NO.sub.x emission can be optimized by determining and controlling the efficiency. This can be performed by making the measured and determined efficiencies equal to one another by altering the air/fuel ratio.

Abstract: According to the present invention, an apparatus and method for controlling injection timing and power balancing in a gaseous fuel engine with an electronic control unit and a shaft encoder is disclosed. The engine includes an engine block having at least one cylinder with an exhaust port and a cylinder head. A fuel injector and a spark plug is seated in the cylinder head and the injector has a valve which separates the fuel in the injector from the cylinder. A piston reciprocates in each cylinder and is attached to a connecting rod. The rod connects each piston to a crankshaft which converts the motion of the piston to rotary motion. The shaft encoder is connected to the crankshaft and monitors the revolutions of the crankshaft. The electronic control unit is coupled to the shaft encoder and to each of the fuel injectors. The method in accordance with the invention includes several steps.

Abstract: A control system for an internal combustion engine having a pressurized gaseous fuel source, a control valve for regulating the amount of gaseous fuel supplied from the pressurized gaseous fuel source, and an intake passage in which the gaseous fuel, the amount of which has been regulated by the control valve, is mixed with intake air and supplied to the engine as an air-fuel mixture. An ECU of the control system controls the air-fuel ratio of the air-fuel mixture to be supplied to the engine by regulating the amount of the gaseous fuel through the control valve, and various sensors detect operating conditions of the engine. The ignition timing of the engine is calculated based on the detected operating conditions, and when the air-fuel ratio of the air-fuel mixture is in a predetermined lean limit region, the output of the engine is controlled by correcting the ignition timing.

Abstract: An engine control unit for a gas fuelled internal combustion engine detects engine speed, throttle position, manifold absolute pressure, gas pressure, gas temperature, battery voltage, air temperature, engine phase and boost pressure control valve feed back position. The control unit calculates a percentage full load value for the engine based upon the detected engine speed and throttle position and utilizes the calculated percentage full load value to calculate the injector on time for each gas injector in a gas delivery system for the engine. Typically, the control unit employs the percentage full load value and the engine speed to calculate a required manifold absolute pressure value, and this calculated manifold absolute pressure value may then be employed together with the percentage full load value to calculate a percent allowable load value. The engine control unit employs the percentage allowable load value to calculate injector on time and spark advance for the engine.

Abstract: A gas mass flow sensor for sensing a flow of compressed natural gas into an internal combustion engine is disclosed including a main flow passage having an inlet and an outlet forming a flow passage for the flow of compressed natural gas to the internal combustion engine, a secondary flow passage positioned within the main flow passage, a compressed natural gas flow sensor positioned within the secondary flow passage for sensing the flow rate of compressed natural gas through the secondary passage and a compressed natural gas flow conditioner for conditioning the flow of compressed natural gas through at least the secondary flow passage. The compressed natural gas flow conditioner includes a plurality of screening elements positioned substantially transversed to a direction of the flow of compressed natural gas through the flow sensor and a plurality of spacers for spacing each of the adjacent screening elements from one another.

Abstract: An integrated premixture chamber is disclosed, for mixing gaseous fuel and air for delivery to a combustion chamber of an internal combustion engine. The integrated premixture chamber includes a mass air flow sensor, a throttle valve and position sensor, a fuel shut-off valve, a gas flow sensor and a fuel metering valve having discharge outlets downstream of the mass air flow sensor to provide more accurate metering. The integrated premixture chamber is controlled by an electronic unit separate from the engine's control unit.

Abstract: A method of controlling operation of a compressed natural gas vehicle as a function of a predetermined level of methane in the ambient. Vehicle ignition is turned off when a predetermined level of methane is sensed in the ambient.

Abstract: A fluid flow control system which can function under a range of input pressures for regulating the flow of fluid as a function of a variable input voltage and having a feedback feature which produces an electrical signal equivalent to the volume of fluid actually flowing from the control system, comprising a pressure balanced valve, a proportional solenoid having a movable shaft responsive to the input voltage and adapted to open the valve, said valve including, a fluid intake chamber having an intake port and a valve port, a fluid discharge chamber having a discharge port, a valve disk and a cooperating valve seat where the valve disk is connected to the shaft of the proportional solenoid so as to open and close the valve, a flexible diaphragm having a centrally disposed piston in contact with the valve disk a pressure equalizing chamber contiguous to the diaphragm, a biasing spring in contact with the piston and exerting a force thereon in a direction toward the valve disk for normally maintaining the valve

Abstract: A fuel-air mixer body (12) includes a mixer passage (14) extending therethrough with a fuel release body (24) positioned centrally within the mixer passage. A flow control section (28) of the mixer passage (14) is defined between the inner wall (20) of the mixer passage (14) and the outer wall of the fuel release body (24), and includes a flow restricting section (30) and a flow area increasing section (32). As input air to be mixed with fuel for combustion flows through the mixer passage (14), a relatively high pressure area is formed in the flow restricting section (30), a first pressure reduction area is produced in the flow area increasing section (32), and a second pressure reduction area is produced downstream from the fuel release body (24). Gaseous fuel may be released into the air flow at two separate locations. The first location is in the flow area increasing section (32) and the second location is at the end of the fuel release body (24).

Abstract: An improved fuel supply system (20), fuel tank (22 or 50), and fuel (30), whose use in small internal combustion engines provides greatly reduced emissions, longer engine life, reduced maintenance, higher reliability, and safety. These fuel tanks (22 or 50) are partially filled with a LPG fuel (30) and are also connectable to the fuel supply system (20) by a corresponding fuelling receptor (32 or 56). The fuel system (20) is itself comprised, in combination, of a fuelling receptor (32 or 56) which is then followed in series and in fuel flow communication by a fuel conduit (36), a fuel lock valve (38), another fuel conduit (40), a primary pressure regulator (42), still another fuel conduit (44), and finally a fuel-air mixer (46).

Abstract: A system and method for selectively refueling a plurality of vehicle storage tanks with compressed natural gas (CNG) are provided that utilize a compressor system operable at suction pressures ranging from about 330 to about 3600 psig and discharge pressures ranging from about 330 to about 4500 psig in combination with a tank for temporarily storing CNG at an intermediate storage pressure of from about 330 to about 4500 psig, preferably from about 1700 to about 2700 psig, apparatus for selectively filling vehicle storage tanks with CNG from an inlet source, from the compressor discharge and from the intermediate storage tanks, and apparatus for selectively supplying CNG to the compressor inlet at either the available line pressure or the intermediate storage pressure.

Abstract: The fueling station consists of a vacuum insulated storage vessel for storing a large quantity of LNG at low pressure. The LNG is delivered to one of two relatively small volume fuel conditioning tanks where the pressure and temperature of the LNG can be raised or lowered as dictated by the needs of the system. The pressure and temperature in the fuel conditioning tanks are raised by delivering high pressure natural gas vapor thereto from a high pressure bank. The temperature and pressure can be lowered by venting natural gas from the fuel conditioning tanks and/or delivering LNG thereto. The fuel conditioning tanks are connectable to a vehicle's fuel tank via a fill line to deliver natural gas and LNG to the vehicle and to vent natural gas from the vehicle to the fueling station.

Abstract: An fuel injection control system suitable for use with internal combustion vehicle engines fueled by compressed natural gas or the like. A liquid-fuel type closed-loop system, modified for gaseous fuel, establishes the duration of each injection command signal by the combination of a P.I.D. controller responsive to the level of exhaust oxygen, an adaptive table which stores previously determined fuel delivery rate values for particular engine speed and load conditions, an injector supply voltage table and an added table modifies the fuel delivery rate correction values which compensate for unwanted pressure variations which occur in the fuel supply due to injector sequencing effects, firing order, fuel flow effects, temperature effects, and fuel sensor errors.

Abstract: An internal combustion engine in which each cylinder is connected to sources both of air and of fuel held as a gas under pressure and in which the compression stroke, during which a full charge of air is drawn and compressed, is substantially completed before the fuel charge is then admitted and the mixture ignited to start the subsequent power stroke. The fuel may be admitted through a unit doubling as admission valve and igniter, and conventional diesel or gasoline-fuelled engines may be converted by designing that unit to fit into the conventional injector or spark plug holes. The compressed gaseous fuel may be methane, or other natural gas. The invention includes both stationary and mobile engines, especially automobile engines, and methods of operating them.

Abstract: Several embodiments of engines and systems for fueling engines to reduce the emission of unwanted exhaust gas constituents and to improve the fuel economy of the engine. A catalytic converter is provided in the exhaust system and a gaseous fuel is used at least during starting so as to bring the catalytic converter up to its operating temperature rapidly without necessitating the provision of an enriched fuel/air mixture. An oxygen sensor is employed in the exhaust system and a feedback control system varies the fuel/air ratio of the engine during its running in response to the output of the oxygen sensor. In order to test that the oxygen sensor is at its operating condition before feedback control is initiated, a rich fuel mixture is supplied and this rich fuel mixture is discontinued immediately upon the receipt of a signal from the oxygen sensor indicating that a rich mixture exits. Applications of the principal to both air valve type of carburetors and conventional carburetors are disclosed.

Abstract: A mixer for a gas fueled engine uses a venturi through which a fuel nozzle opens into an air inlet path at a narrowest portion of the venturi in a substantially parallel orientation relative to the flow of inlet air in the air inlet path to reduce the mixture loss, and an air nozzle opens into the air inlet path at an expanding portion of the venturi in a substantially parallel orientation relative to the flow of the inlet air to reduce the ventilation resistance caused by a boundary layer and to make a uniform mixture of the gaseous fuel and the air.

Abstract: A fuel delivery system which includes a source of pressurized fuel (18-22), at least one fuel injector (14) in fluid communication with the source (18-22), a pressure regulator (34) for delivering the pressurized fuel to the fuel injector (14), a pressure sensor (40) for providing an indication of pressure at the fuel injector (14), a controller (42) responsive to the pressure sensor (40) for providing a pressure release signal, and a pressure release system (44) responsive to the pressure relief signal for diverting a portion of the pressurized fuel from the fuel injector (14).

Abstract: An integrated refueling system comprises a fluid circuit including multiple flow paths for directing natural gas to a natural gas liquefier. A portion of the resulting liquefied natural gas is provided to a liquefied natural gas delivery location. Another portion of the liquefied natural gas may be provided to a compressor and subsequently a heat exchanger/vaporizer to produce compressed natural gas. The heat exchanger/vaporizer may utilize the lower temperature of liquefied natural gas to precool incoming gaseous natural gas while simultaneously vaporizing the pressurized, liquefied natural gas to form the compressed natural gas. Compressed natural gas may be provided at a compressed natural gas delivery location.

Abstract: A generator powered by an internal combustion engine is fueled from a source of biogas. A pump boosts the pressure of the biogas, and a regulator controls the biogas pressure supplied to the fuel intake of the engine carburetor. Acid-neutralizing oil is injected into the biogas stream at the intake of the pump to protect the engine from corrosion due to acidic constituents in the biogas.

Abstract: The delivery system of the invention consists of a pair of LNG fuel tanks mounted on a vehicle. A solenoid valve associated with each tank allows the vehicle operator to select the tank from which LNG is to be delivered to the engine. An automatic override system is provided whereby if the pressure in the non-selected tank rises above a predetermined level, the operator's tank selection is overridden and gas from the non-selected tank is used until the pressure falls below the predetermined level. This override system eliminates the need to vent gas to the atmosphere to avoid pressure building up and thereby eliminates waste of the LNG. Each tank is also provided with a pressure building capability such that the gas will always be delivered to the engine with sufficient pressure. The system is designed such that LNG from a stationary low pressure storage tank can be delivered at high pressure to refuel the tanks.