Abstract: A liquified gas delivery system for a motorized platform includes a holding tank configured to receive liquified gas. A first conduit extends from a vapor holding portion of the tank to a valve device. A second conduit extends from a liquid holding portion of the tank to the valve device. Fluid coupled to the valve device is a vaporizer which is in communication with an engine. The valve device selectively withdraws either liquified gas or liquified gas vapor from the tank depending on the pressure within the vapor holding portion of the tank. Various configurations of the delivery system can be utilized for pressurizing the tank during operation.

Abstract: LPG decompressed in a regulator is fed as primary fuel into an intake passage from a carburetor, and is fed as supplementary fuel to the intake passage from an injector. An ECU controls a control variable for the injector to cause an air/fuel ratio detected in an oxygen sensor to be a stoichiometric air/fuel ratio. At idle operation, an optimum state of the control variable with respect to a target value is output from a monitor terminal and is monitored, and an adjusting screw in a slow passage is operated and adjusted to cause the control variable to be the target value. An adjustment range for the control variable is set into two stages through operation of the test terminal. The ECU controls an output pattern of a monitor terminal in individual adjustment ranges at each stage, according to whether or not the control variable falls within the adjustment range.

Abstract: A fuel injection system for a gaseous-fueled engine is provided. The fuel injection system comprises at least one gaseous fuel injector for each of the engine cylinders, wherein each fuel injector is located proximate the intake manifold. A guide tube connects each of the gaseous fuel injectors to at least one of the intake ports. The guide tube comprises a fluid passage arranged within the respective intake port substantially tangent and adjacent to an interior wall of the intake port and directed toward the respective intake valve. The guide tube is adapted to deliver high-pressure gaseous fuel from the injector to the respective combustion chamber along the interior wall of the intake port. In this way, the high velocity peripheral fuel charge creates a lower pressure central core within the intake part which, in turn, increases the overall intake charge flow and engine volumetric efficiency.

Abstract: An improved structure for carburetor is mainly comprised of casing, throat, air calibrating cone, ring-shaped throttling hole, and air assisting pore device, etc.

Abstract: The invention relates to a method for operating a four-stroke internal combustion engine with natural gas. In this method, at high to full torque operating conditions, the natural gas is injected directly into the cylinder of the engine toward the end of the induction stroke or at the start of the compression stroke. This may take place in particular in a crank angle range between 210° and 90° before top dead center. The efficiency of the engine is thus improved without generating a gas pressure higher than the storage pressure. It is preferable for the engine to be operated with a stoichiometric air/fuel ratio.

Abstract: A method of utilizing a methane-containing gas by feeding the methane-containing gas to a gas engine of a gas engine/generator assembly generating electricity comprises the step of passing combustion air containing an inert gas through a membrane separating installation to reduce the content of the inert gas before feeding the combustion air to the gas engine.

Abstract: The invention is directed to a fuel delivery valving and hosing system comprising a fuel source coupled to a regulator, a regulator coupled to a hose; a hose coupled to an automatic shut off valve, a hose coupled to a manual shut off valve, a hose coupled to T-junction, a hose from the T-junction coupled to a low RPM valve, a hose from the low RPM valve coupled to a second T-junction, the second T-junction coupled to a preset high RPM run valve and a hose from second T-junction coupled back to a high RPM run valve and to complete a loop. A hose from the preset high RPM flow-limiting valve goes to an injector, and the injector is coupled to an engine/power plant at the carburetor, carburetor insulator or manifold. The present invention will be highly efficient at regulating and controlling gaseous fuels supplied to the engine and produce cleaner emissions.

Abstract: In a fuel gas mixer 1 comprising a throttle valve 4 provided in an air intake passage 2 connected to an engine for opening and closing the air intake passage 2 and a fuel gas supply passage 6 connected to the air intake passage 2 upstream of the throttle valve 4. A fuel gas control valve 5 is provided in the air intake passage 2 upstream of the connecting part of the fuel gas supply passage 6 for opening and closing the air intake passage 2, and a fuel gas control valve controlling means 11 is provided for varying the degree of the opening of the fuel gas control valve 5 depending upon the operating state of the engine.

Abstract: A methane gas control system, including a blower having an inlet for generating an air stream and a discharge section for expelling the air stream from the blower, a fuel collector attached to the blower at the discharge section for collecting methane gas contained in the air stream, a heated dryer connected to the fuel collector for eliminating moisture from the methane gas, and an engine connected to the heated dryer that is at least partially fueled by the methane gas. In operation, the methane gas control system removes methane from a borehole by generating and collecting an air stream from the borehole using a blower, collecting methane contained in the air stream using a fuel collector, removing moisture from the methane using a heated dryer, and transporting the methane from the heated dryer to an engine that is at least partially fueled by the methane gas.

Abstract: Gas injection system, particularly of methane, for an internal combustion engine, comprising a plurality of electromagnetically controlled injectors associated to the various cylinders of the engine, a gas distributing manifold communicating with the injectors, a reservoir feeding the distributing manifold, where the pressurised gas is accumulated.

Abstract: The invention is in a regulator and converter operated to fumigate a volatile material, preferably a liquified petroleum gas (LPG), under vacuum, into an intake air flow of an internal combustion diesel engine to provide, on demand generated by an operator closing a throttle, passage of LPG to the regulator and converter wherein it is vaporized and the LPG vapors are passed into the engine intake air flow that travels into the engine. The injection of LPG vapors provides for an increase in engine output power and an improvement in fuel percentage of burn. The regulator and converter is connected the engine coolant system to receive a hot coolant flow, heating an LPG flow path therethrough to vaporize the LPG with the LPG vapors then directed from the regulator and converter into the engine intake air flow.

Abstract: Fuel storage and delivery systems for compressed natural gas are provided that are constructed from ultra-high strength, low alloy steels containing less than 2.5 wt % nickel and having a tensile strength greater than 900 MPa (130 ksi). A primary benefit is that systems of this invention have substantially lower weight than that of currently available steel-based systems. Consequently, the fuel efficiency of a CNG vehicle can be improved due to the lower weight of the system of this invention, or the driving range of the CNG vehicle can be improved by increased fuel storage for the same volume at an elevated pressure, or the load-carrying capacity of the CNG vehicle can be improved. Another primary benefit is that systems of this invention have a cost per unit strength substantially lower than that of currently available systems.

Abstract: A vehicle gaseous fuel supply system includes a high pressure filter, a primary pressure-reducing valve, a solenoid cut-off valve, safety means, and a secondary pressure-reducing valve. A regulator is formed by disposing the high pressure filter, the solenoid cut-off valve, and the primary pressure-reducing valve on a common regulator body that has a passage providing a connection between the high pressure filter and the solenoid cut-off valve, a passage providing a connection between the solenoid cut-off valve and the primary pressure-reducing valve, and an exit passage having one end connected to the primary pressure-reducing valve. Between the safety means and the secondary pressure-reducing valve which are connected to the other end of the exit passage, at least the secondary pressure-reducing valve has its valve housing formed as a body separate from the regulator body.

Abstract: A fuel injection system for a gaseous-fueled engine is provided. The engine comprises a plurality of cylinders each defining a combustion chamber and associated with at least one intake port in fluid communication with an intake manifold and separated from the combustion chamber by an intake valve operable between an open and closed position. The fuel injection system comprises at least one gaseous fuel injector for each of the engine cylinders, wherein each fuel injector is located proximate the intake manifold. A guide tube connects each of the gaseous fuel injectors to at least one of the intake ports. The guide tube comprises a fluid passage arranged within the respective intake port substantially tangent and adjacent to an interior wall of the intake port and directed toward the respective intake valve. The guide tube is adapted to deliver high-pressure gaseous fuel from the injector to the respective combustion chamber along the interior wall of the intake port.

Abstract: A system and method for transferring heat from the exhaust of an internal combustion engine to a fuel container storing compressed gas fuel, using a gaseous heat transfer medium. The heat transferred to the fuel container assists expansion and/or vaporization of the compressed gas fuel. The expanded and/or vaporized compressed gas fuel may be delivered to the internal combustion engine for use by the engine.

Abstract: A gas fuel system for a bi-fuel engine includes an injector block assembly that supports gas fuel injectors between an injector block and an inlet header. The block assembly may be mounted beside or behind the engine remote from the engine intake ports where gasoline fuel or gaseous fuel (gas) may be injected for powering the engine. The block assembly connects the injectors through individual distribution lines with separate port openings of an adapter plate mounted between the air intake manifold and the engine intake ports to provide for injection of gas to the intake ports from the remote location. Mounting of the injectors in the remote block assembly, which feeds the adapter, avoids changes to a developed gasoline fuel system in the engine, thus reducing development and production costs. The block assembly may also be modified to use other available gas injectors without affecting the conventional engine components.

Abstract: In an internal combustion engine, the fuel reaches the combustion chamber of the engine via a fuel-injection device which includes a piezo actuator (50). In order to be able to optimally inject the fuel, it is suggested that the desired level (U_DES) of the drive energy (U) and/or the desired gradient (dU_DES) of the drive energy (U), with which the piezo actuator (50) is driven, is dependent upon a plurality of influence quantities (T, t, n, dx, dh) which influence the operating behavior of the piezo actuator (50).

Abstract: A GPL fuel system for an internal combustion engine, including a GPL fuel tank and a pump immersed in the fuel tank and driven by an electric motor, the pump being kept constantly running when the temperature is below 0° C. or above 80° C., whilst the supply voltage of the electric motor driving the pump is chopper-controlled when the temperature is between the two said values.

Abstract: Gas metering system for an internal combustion engine. A gas pressure regulator is connected to a venturi located in the inlet of the internal combustion engine through a main adjusting screw being electrically adjustable. The control is provided in which engine rpm, load and mixture temperature are inputted. To provide for applicability for different types of engines and to obtain the ideal air fuel ratio for each operating condition, the control module of the adjustable main adjusting screw is provided with adjusting means. The surface area of the gas outflow openings in the venturi throat is the only required information for the control module to identify different types of engines and fuels and to adjust the gas flow automatically.

Abstract: A system for an automobile has a compressed fuel source (14) having a first fuel pressure. An expansion device (26) is coupled to the compressed fuel source (14) and reduces the first pressure to a second pressure lower than the first pressure. The expansion device (26) generates a first quantity of work and forms a reduced pressure fuel. A chemical energy conversion engine (16) is coupled to the expansion device (26) and receives a reduced pressure fuel. The chemical energy conversion engine (16) generates a second quantity of work in response to the decompressed fuel. In one aspect of the invention, the first quantity of work and the second quantity of work may be coupled to an output shaft (20) such as the crankshaft of an internal combustion engine. In another aspect of the invention, the first quantity of work may be coupled to an accessory (40) either directly or indirectly. Indirect coupling may, for example, be performed using an accessory drive belt of the internal combustion engine.

Abstract: A mixer for a multicylinder gas engine is provided in which a plurality of intake passages extend to a plurality of cylinders. A plurality of gaseous fuel nozzles, each having a nozzle orifice opening in a venturi part of the corresponding intake passage, are provided in a mixer main body. The plurality of gaseous fuel nozzles are connected to a gaseous fuel supply device, wherein a common surge tank housing the plurality of gaseous fuel nozzles and having a fuel intake pipe opening therein is provided on the mixer main body. The fuel intake pipe extends to the gaseous fuel supply device. Intake pressure pulsations that have passed through the gaseous fuel nozzles are attenuated within the surge tank, thereby achieving uniform distribution of a gaseous mixture to each cylinder, minimizes the number of parts, and prevents fluctuations in the fuel concentration of the gaseous mixture.

Abstract: A fuel metering assembly for a natural gas fuel engine having an engine block from a diesel engine with a diesel engine injector pump flange integrally cast as part of the engine block. The metering assembly has inlet and outlet manifolds for fuel and a plurality of fuel injectors therebetween. The manifolds are held in a fixed position relative to one another by a plate on one end that fits to the injector pump flange on the engine block to mount the metering assembly to the existing flange. In addition, the inlet manifold includes pressure and temperature sensors inside the inlet manifold to sense pressure and temperature at the point of metering.

Abstract: An integrated fuel control unit for gas-operated internal combustion engines that includes a base on which a primary diaphragm is secured to define a primary fuel chamber. A primary fuel orifice is carried by the base, as is a primary control lever that is coupled to the primary diaphragm for controlling flow of fuel through the primary orifice as a function of inlet fuel pressure and engine demand. A secondary diaphragm is also secured to the base to define a secondary fuel chamber. A secondary orifice is carried by the base between the primary and secondary chambers, and a secondary control lever is coupled to the secondary diaphragm for controlling flow of fuel through the secondary orifice as a function of engine demand. A heat exchange section in the body receives engine coolant or engine oil for heat exchange with fuel so as to heat and vaporize the fuel between the primary and secondary chambers.

Abstract: A liquified gas delivery system for a motorized platform includes a holding tank configured to receive liquified gas. A first conduit extends from a vapor holding portion of the tank to a valve device. A second conduit extends from a liquid holding portion of the tank to the valve device. Fluid coupled to the valve device is a vaporizer which is in communication with an engine. The valve device selectively withdraws either liquified gas or liquified gas vapor from the tank depending on the pressure within the vapor holding portion of the tank. Various configurations of the delivery system can be utilized for pressurizing the tank during operation.

Abstract: A liquified gas delivery system for a motorized platform includes a holding tank configured to receive liquified gas. A first conduit extends from a vapor holding portion of the tank to a valve device. A second conduit extends from a liquid holding portion of the tank to the valve device. Fluid coupled to the valve device is a vaporizer which is in communication with an engine. The valve device selectively withdraws either liquified gas or liquified gas vapor from the tank depending on the pressure within the vapor holding portion of the tank. Various configurations of the delivery system can be utilized for pressurizing the tank during operation.

Abstract: A fuel supply for an internal combustion engine includes providing a source of a first fluid fuel and a source of a second fluid fuel which are separate from one another, sensing at least one operational parameter of an internal combustion engine, supplying the first fuel from the one source and the second fuel from the other source in quantities which are determined in correspondence with the sensed operational parameter of the internal combustion engine, and mixing the first fuel and the second fuel in with the quantities determined in correspondence with the sensed operational parameter so as to produce a fuel mixture to be supplied to the internal combustion engine.

Abstract: A liquified gas delivery system for a motorized platform includes a holding tank configured to receive liquified gas. A first conduit extends from a vapor holding portion of the tank to a valve device. A second conduit extends from a liquid holding portion of the tank to the valve device. Fluid coupled to the valve device is a vaporizer which is in communication with an engine. The valve device selectively withdraws either liquified gas or liquified gas vapor from the tank depending on the pressure within the vapor holding portion of the tank. Various configurations of the delivery system can be utilized for pressurizing the tank during operation.

Abstract: A system and method for transferring heat from the exhaust of an internal combustion engine to a fuel container storing compressed gas fuel, using a gaseous heat transfer medium. The heat transferred to the fuel container assists expansion and/or vaporization of the compressed gas fuel. The expanded and/or vaporized compressed gas fuel may be delivered to the internal combustion engine for use by the engine.

Abstract: A means for positioning one or more bottom fed-side ejecting fuel injectors at the inlet of an internal combustion engine, attachable to the air inlet duct or air cleaner assembly, with connected tubes that carry fuel ejected from the injectors through one or more holes in said air cleaner or inlet ducting to optimal points proximate to the engine inlet.

Abstract: A gas injection device in which an tunnel-like inner room is formed by surrounding with an inner wall, the inner room is communicated to the intake air flow passage of the intake pipe to allow the intake air to flow through the inner room, the inner wall is surrounded with an outer wall to form between the inner wall and outer wall an outer gas chamber into which fuel gas is introduced, and gas injection holes are provided in the inner wall to permit the gas in the outer gas chamber to sprout out from the injection holes into the air stream flowing through the inner room. The inner room may be partitioned into a plurality of tunnel-like rooms to correspond to the number of the intake air passages in the cylinder head.

Abstract: One embodiment of the present invention includes sensing speed or an internal combustion engine that includes a manifold coupled to an air pathway and a gaseous fuel line, sensing manifold pressure, and sensing manifold temperature. Air mass flow rate is determined as a function of the sensed engine spaced, manifold pressure, and manifold temperature. Fuel mass flow rate in the fuel line is sensed and fuel is controlled through the fuel line in accordance with the air mass flow rate and the fuel mass flow rate.

Abstract: A ventilation system (11) is provided to prevent the buildup of gaseous fuel within the vehicle upon degradation of the performance of the various parts within the fuel distribution system. The vehicle (10) has a combustible gas fuel source within the vehicle. The ventilation system includes a fuel line (28) coupling the engine (18) and the gas source. A vent line (30) is coupled to a vent. A pressure regulator (56) and pressure relief valve (60) are coupled between fuel line (28) and vent line. When either or both the pressure regulator (56) or relief valve (60) become inoperable, gaseous fuel is coupled to the vent line.

Abstract: On-off valve intended to be arranged at the outlet of the gas accumulation reservoir in an electronic gas injection system for an internal combustion engine, presenting a valve member made of metallic material, co-operating with a valve seat made in a body, which is also made of metallic material, to ensure the good quality of tightness in all operative temperature and pressure conditions, with prolonged reliability in time.

Abstract: A novel flow sensor that includes a valve responsive to a pressure differential or pressure drop across a selectively sized restriction orifice. The flow sensor may be incorporated into a high-pressure fuel injection system for sensing the opening and closing of high pressure fuel injector for injecting gaseous fuel.

Abstract: A compact and efficient rotary pressure swing adsorption (PSA) apparatus with laminated sheet adsorbers is used to supply enriched oxygen and/or nitrogen streams to an internal combustion engine, allowing for reduced noxious emissions and enhanced engine performance.

Abstract: A gas fuel system for a bi-fuel engine includes an injector block assembly that supports gas fuel injectors between an injector block and an inlet header. The block assembly may be mounted beside or behind the engine remote from the engine intake ports where gasoline fuel or gaseous fuel (gas) may be injected for powering the engine. The block assembly connects the injectors through individual distribution lines with separate port openings of an adapter plate mounted between the air intake manifold and the engine intake ports to provide for injection of gas to the intake ports from the remote location. Mounting of the injectors in the remote block assembly, which feeds the adapter, avoids changes to a developed gasoline fuel system in the engine, thus reducing development and production costs. The block assembly may also be modified to use other available gas injectors without affecting the conventional engine components.

Abstract: A vehicle gaseous fuel supply system includes a high pressure filter, a primary pressure-reducing valve, a solenoid cut-off valve, safety means, and a secondary pressure-reducing valve. A regulator is formed by disposing the high pressure filter, the solenoid cut-off valve, and the primary pressure-reducing valve on a common regulator body that has a passage providing a connection between the high pressure filter and the solenoid cut-off valve, a passage providing a connection between the solenoid cut-off valve and the primary pressure-reducing valve, and an exit passage having one end connected to the primary pressure-reducing valve. Between the safety means and the secondary pressure-reducing valve which are connected to the other end of the exit passage, at least the secondary pressure-reducing valve has its valve housing formed as a body separate from the regulator body.

Abstract: A method and apparatus for introducing gaseous fuel into a piston cylinder of an operating internal combustion engine in two separate stages involves monitoring a set of engine parameters, determining engine load and engine speed from the set of engine parameters, in a first stage, introducing a first portion of the gaseous fuel into the cylinder where the first portion of gaseous fuel forms a substantially homogeneous mixture comprising gaseous fuel and air prior to combustion, and in a second stage, occurring sequentially after the first stage, introducing a second portion of the gaseous fuel into the cylinder. The gaseous fuel quantity is variable in response to at least one of engine load and engine speed. Initiation and duration for at least one of the first and second stages is also variable in response to at least one of engine load and engine speed.

Abstract: In a method of utilizing a methane-containing biogas by feeding the methane-containing biogas to a gas engine of a gas engine/generator assembly generating electricity, the steps of passing the biogas through a membrane separating installation to divide the biogas into a first gas stream having a higher methane content than the biogas fed thereto and a second gas stream enriched in CO2, feeding the first gas stream to the gas engine as fuel, and returning the second gas stream to the source of the biogas.

Abstract: The invention relates to a method and an apparatus for conveying a cryogenically-stored fuel to an internal-combustion engine for providing a combustible working gas. In accordance with the invention, the cryogenically-stored fuel is drawn, in the liquid state, from a thermally-insulated fuel tank, and forced into a fuel line by a conveying device. At least from time to time, within the scope of the operation of the conveying device, the pressure in the fuel tank is increased by an amount that is larger than the difference between a drop in the supply-flow pressure occurring on the intake side of the conveying device and the difference between the dominant tank pressure at a pump-inlet point and the boiling pressure dictated by the instantaneous fuel temperature.

Abstract: Injectors 2 are connected to a common rail 4 via respective dispensing conduits 3. A mixture of a liquid fuel fed from a liquid fuel tank 2 and an additional fluid fed from an additional fluid tank 9 is formed, and is fed to the common rail 4. The additional fluid contained in the mixture is turned to its supercritical state, and the mixture is injected from the injectors 2 to the engine. The inlets of the dispensing conduits 3 are positioned, with respect to the common rail 4, to open out into a liquid fuel layer which will be formed in the common rail 4 when a separation of the mixture occurs.

Abstract: Gas injection system, particularly of methane, for an internal combustion engine, comprising a plurality of electromagnetically controlled injectors associated to the various cylinders of the engine, a gas distributing manifold communicating with the injectors, a reservoir feeding the distributing manifold, where the pressurised gas is accumulated.

Abstract: The system includes a metering valve for each cylinder including a main valve and an auxiliary valve. The auxiliary valve is electrically controlled ad via a mechanical, pressure controlled amplifier mechanism, the main orifice in the metering valve is opened.

Abstract: This invention is directed to an apparatus and method for providing improved control of fuel, preferably gaseous fuel, to an internal combustion engine such that each cylinder of the engine will operate within a predetermined tolerance off of its lean misfire limit. The disclosed system introduces fuel to the engine at two locations: (1) upstream of the intake manifold to provide premixing of a majority of the fuel with air, and (2) near the intake valve of each cylinder for tailoring the fuel flow to each cylinder to achieve that fuel-to-air ratio which is necessary to maintain each cylinder at the desired tolerance from the lean misfire limit. Several calibration and control methods are described to maximize performance of the fuel system, including the use of a misfire detection technique to determine the lean misfire limit of each cylinder to allow the respective port fuel injector to provide a specified margin from lean misfire.

Abstract: An apparatus and method for utilizing any arbitrary mixture ratio of multiple fuel gases having differing combustion characteristics, such as natural gas and hydrogen gas, within an internal combustion engine. The gaseous fuel composition ratio is first sensed, such as by thermal conductivity, infrared signature, sound propagation speed, or equivalent mixture differentiation mechanisms and combinations thereof which are utilized as input(s) to a “multiple map” engine control module which modulates selected operating parameters of the engine, such as fuel injection and ignition timing, in response to the proportions of fuel gases available so that the engine operates correctly and at high efficiency irrespective of the gas mixture ratio being utilized. As a result, an engine configured according to the teachings of the present invention may be fueled from at least two different fuel sources without admixing constraints.

Abstract: A methane gas control system, including a blower having an inlet for generating an air stream and a discharge section for expelling the air stream from the blower, a fuel collector attached to the blower at the discharge section for collecting methane gas contained in the air stream, a heated dryer connected to the fuel collector for eliminating moisture from the methane gas, and an engine connected to the heated dryer that is at least partially fueled by the methane gas. In operation, the methane gas control system removes methane from a borehole by generating and collecting an air stream from the borehole using a blower, collecting methane contained in the air stream using a fuel collector, removing moisture from the methane using a heated dryer, and transporting the methane from the heated dryer to an engine that is at least partially fueled by the methane gas.

Abstract: A heater for gas fuel mounted to a pressure reducing regulator to warm the gas after the temperature is reduced by the pressure reduction. The heater receives the fuel from the regulator through an external pipe and has separate gas and coolant passages therein. The coolant passage receives liquid engine coolant that heats both the gas and the regulator. A heater core has a plurality of radially extending fins around which the gas passes with the coolant passing through the interior of the core. Coolant flow is regulated by a thermostat that is responsive to the temperature of the gas to open and close the coolant passage.

Abstract: A gas flow regulation module is provided comprising, a body, including a longitudinal axis, and including a first port and second port, a first fluid passage extending from the first port, and a second fluid passage extending from the second port; and a regulator, mounted to the body and disposed in communication with the first and second fluid passages, including a moveable pressure boundary member characterized by a transverse axis which is substantially perpendicular to the longitudinal axis of the neck.

Abstract: A method for controlling the air-fuel ratio in a natural gas engine having an air-fuel mixing device, comprises: determining a speed set-point and an actual engine speed, determining a fuel command based on said speed set-point and said engine speed and controlling the fuel flow to the air-fuel mixing device in response to said fuel command. An air-fuel control system for natural gas engines, comprises: means to determine a speed set-point and an actual engine speed, a governor control unit for generating a fuel command based on said speed set-point and said actual engine speed and a fuel flow regulator coupled to said governor control unit for regulating the flow of fuel to an air-fuel mixing device in response to said fuel command.

Abstract: A gas engine operated machine includes a machine unit that includes an engine burning a gas fuel, and a working device driven by the engine, the machine unit being surrounded by and fixed to a rigid frame formed by framing an elongated frame material, and an upper portion of the machine unit being covered with a roof, such that the operated machine is easy to handle and attractive in appearance, and it is possible to effectively avoid another object colliding against piping parts such as a gas fuel pressure regulator and the like, or rain water, dust and the like striking against the piping parts, thereby stabilizing the operation of the piping parts and enhancing the durability of the piping parts. A roof includes an upper cover bulged upwards, and a lower cover mounted to a lower surface of the upper cover, and supported on a rigid frame through vibration-damping members.