Abstract: The invention relates to a fuel pumping device for two-cycle engines with at least a one-piece housing, on which a pulse air connector (14), which is pneumatically connected with the crankcase of the two-cycle engine, a fuel aspiration connector and a fuel pressure connector are arranged, in which a diaphragm (41) on which pulse air acts, drives a pump piston (22) in connection with a diaphragm disk (42), in the course of which fuel being supplied from the tank (1) at the fuel aspiration connector during the pump aspiration stroke is aspirated via a flap valve (61) into the compression chamber (51) located upstream of the pump piston, and is pumped during the compression stroke via a further flap valve (71) into the fuel pressure connector and into a reservoir (73) and/or an injection valve (5). The pulse air connector (14) terminates in a housing chamber (13) located between the diaphragm (41) and the pump piston (22), and at least one spring element (15, 35, 94) acts on each side of the diaphragm (41).

Abstract: An engine control scheme determines the appropriate and desired magnitude of scavenging air flow for a two stroke engine as a function of both load and engine speed. The desired air flow is determined, as a function of engine load and engine speed, to achieve an optimal magnitude of emissions within the exhaust stream and to also optimize a reverse thrust capabilities of the marine propulsion system.

Abstract: A fuel injection control strategy and system for engines for maintaining good performance under normal running conditions and also for providing cylinder engine speed slow-down under abnormal conditions without necessitating cylinder skipping except in extreme cases. This control is obtained primarily by retarding injection timing and/or reducing injection duration. Adjustment in spark timing may also be incorporated along with this routine.

Abstract: A two-cycle internal combustion engine includes a control valve disposed in a communicating passage for communicating the combustion chamber to a chamber portion adjacent to the combustion chamber. The control valve controls the opening and closing of the communicating passage. A fuel or an air-fuel mixture is supplied into the combustion chamber through the communicating passage. The fuel injection opening of the communicating passage has a height which is smaller than the distance between outermost side surfaces of the piston rings to reduce the amount of the air-fuel mixture or combustion gas leaking from the combustion chamber into the crank chamber through gaps between the piston and the opening. Therefore, reduction in engine output or seizure of the piston due to local temperature rise is avoided.

Abstract: Disclosed is a method for controlling the injection process in a high-speed two stroke internal combustion engine (11). The method includes providing a trigger signal fixedly related to the rotational angle of the crankshaft per revolution of the injection control, providing a speed dependent A.C. voltage, whose period duration amounts to a fraction (L/n) of the time per revolution (rotation time) of the internal combustion engine (11), and controlling the injection process responsive to the trigger signal and the A.C. voltage. Accordingly, the invention provides a simple electronic injection control with optimal, accurately computable injection parameters for all speeds.

Abstract: In order to provide a mixture-compressing two-stroke Otto engine with fuel injection into the cylinder space, in which it is in particular intended to make a homogeneous mixture formation possible, it is proposed that the combustion space (19) possesses essentially the configuration of a hemisphere and, with its combustion space axis (21), is, from the cylinder axis (20) relative to the side of the cylinder (11) located opposite the exhaust duct (14), disposed so as to be offset, the injection nozzle being disposed relative to the combustion space (19 in such a way that the upper portion of the jet cone (22) penetrates a predominant volume proportion of the combustion space (19), while the lower portion of the jet cone extends underneath the cylinder bottom plane (25) approximately obliquely to the cylinder axis (20), but outside the combustion space (19).

Abstract: A two cycle crankcase compression internal combustion engine wherein a single fuel injector is mounted in the cylinder block and can inject either directly into the combustion chamber or into the induction system through the crankcase chamber through a window in the piston. A control strategy is disclosed wherein the injection occurs primarily into the induction system during either or both of startup and low temperature.

Abstract: A two-cycle internal combustion engine implements low-pressure, cylinder wall fuel injection and uses a notched exhaust port or the like to control cylinder pressure rise during exhaust port closure. An electronic control unit controls the operation of fuel injection through the cylinder wall. Fuel injection terminates before the piston closes the exhaust port as the piston travels from bottom dead center to top dead center. The exhaust port notch tempers pressure gradients and pressure fluctuations in the piston cavity that can otherwise occur before the exhaust port closes and can be detrimental to the control of low-pressure fuel injectors. The exhaust port notch allows better fuel injection control, especially at idle or low speeds, without requiring the port positions and configurations to be modified which could compromise engine performance at medium or high speeds.

Abstract: In a method for controlling an injection valve (16) in a high-speed internal combustion engine with fuel injection, in which method, with each revolution of the engine, at a trigger point (TP1,TP2), a trigger signal is generated and according to the trigger signal, the injection operation is initiated, in which, for low engine speeds, the injection start is within a first range (ESB1) of the crankshaft angle of rotation and in which, for high engine speeds, the injection start is within a second range (ESB2) of the crankshaft angle of rotation, which second range (ESB2) in comparison with the first range (ESB1), is displaced in the direction "early" relative to the top dead center (OT), an optimal operating behavior is achieved in that, to each of the two ranges (ESB1 or ESB2), a trigger point of its own (TP1 or TP2) is allocated and in that, when changing between low and high engine speeds, starting from a predetermined threshold engine speed, a changeover of the control between the two trigger points (TP1,T

Abstract: A start-up strategy for engine feedback control that utilizes a combustion condition sensor associated with only one cylinder. On starting and warm-up, only that one cylinder is feedback-controlled at all times. Under these conditions, the amount of corrected fuel supplied to the feedback cylinder is added to a fixed incremental amount of fuel that will be supplied to the remaining cylinders. This promotes smooth warm-up without backfiring or stalling and a quicker transition to all cylinder feedback control.

Abstract: A fuel injection system for a two-stroke cycle engine comprising an air manifold; a throttle valve; a fuel injector; a fuel supply system including a fuel pump; a battery voltage sensor; an air temperature sensor; an engine speed sensor; a timing sensor; a barometric pressure sensor; a throttle position sensor; a first data processor for receiving and processing sensing signals for determining fuel injector duration and timing and fuel pump operating speed; a first data processor temperature sensor for sensing the relative temperature of certain electronic components in the first data processor; a heater operatively associated with the first data processor electronic components for selectively heating the electronic components; and a second data processor operable independently of the first data processor for receiving an electronic component temperature sensing signal and for generating a control signal to the heater responsive thereto for heating the components when the temperature thereof is below a predet

Abstract: A direct injection system and control methodology for two-cycle crankcase compression engines wherein the injection timing is advanced from those normally utilized to avoid the incomplete combustion that results from the prior art method. The injection timing is advanced so that it occurs while the exhaust port is still open but it is timed in such a way that the injected fuel will not be swept out of the exhaust port before the exhaust port closes. The initiation of injection timing is adjusted in response to certain parameters such as engine speed and the volume of intake air flow. In addition, the effects of other cylinders sharing a common exhaust manifold is also compensated for.

Abstract: A number of embodiments of direct injected V-type outboard motors provided with a very effective fuel supply system wherein the number of components can be significantly reduced as well as the elimination of many of the flexible conduits normally employed. This also permits the fuel system to be assembled as a relatively unitary assembly that can be then affixed to the engine. The arrangement is such that purging of the system from vapors during shutdowns is easily accomplished and the system can be purged without complicated construction. Furthermore, the system can be pressure tested by an arrangement where the low pressure system can bypass the high pressure system when the engine is not operating so as to be pressurized for testing purposes. However, when the high pressure system operates, then the bypass line will be closed by the shunting valve arrangement.

Abstract: A control valve is disposed in a communication passage for communication between a combustion chamber and a chamber portion adjacent to the combustion chamber, and through the communication passage at least one of a fuel and an air-fuel mixture, and a highly compressed gas, are supplied or charged into the combustion chamber and the chamber portion adjacent thereto, respectively. The control valve includes a first control valve disposed in the first communication passage and a second control valve disposed in the second communication passage, the first control valve causes the first communication passage to open at a timing near closing of an exhaust port and causes it to close halfway in a compression stroke. The second control valve causes the second communication passage to open at a timing near closing of the scavenging ports and causes it to close prior to closing of the first communication passage.

Abstract: The invention relates to a method of operating an internal combustion engine and to an internal combustion engine respectively. In accordance with the method of operating an internal combustion engine in accordance with the invention fuel is injected into a combustion chamber so that it is reflected by a piston, as a result of which charge stratification occurs in the combustion chamber. Fresh air is inducted slightly throttled or not throttled at all into the combustion chamber irrespective of the loading condition of the internal combustion engine so that the exhaust gases from the previous working stroke are completely swept from the combustion chamber. The output of the internal combustion engine is generated substantially via the injected amount of fuel.Dueto the method in accordance with the invention charge stratification is caused in which burning of the fuel/air mixture is ideal. The internal combustion engine in accordance with the invention thus features smooth running for ideal emission values.

Abstract: A two-cycle internal combustion engine includes a control valve disposed within a communicating passage between the combustion chamber and a chamber portion adjacent to the combustion chamber. The control valve is for controlling the opening and closing of the communicating passage. Blowby of an air-fuel mixture supplied to the combustion chamber can be prevented to reduce fuel consumption and increase the exhaust gas purifying performance. A communicating passage portion between the control valve and the fuel supply opening is configured to spray fuel from the control valve to a part or all of a wall surface of the communicating passage portion and the wall surface of the communicating passage portion is shaped to guide the fuel into the combustion chamber.

Abstract: A control device for a two-cycle internal combustion engine combustion engine of the fuel injection type, which is provided with an ignition control device and a fuel control device, wherein the fuel control device includes an injection mode-controlling means for controlling a timing of fuel injection by selecting a particular fuel injection mode, i.e. selecting the mode from a one-injection per revolution mode where the injection of fuel is performed on every revolution of a crank shaft of the internal combustion engine and a thinned-out injection mode where the injection of fuel is performed on plural revolutions of the crank shaft. The fuel control device is provided also with an injection quantity-controlling means for controlling the quantity of fuel to be injected.

Abstract: A control system for a fuel injector system for an internal combustion engine is provided with a method by which the magnitude of the start of air point for the injector system is modified according to the barometric pressure measured in a region surrounding the engine. This offset, or modification, of the start of air point adjusts the timing of the fuel injector system to suit different altitudes at which the engine may be operating.

Abstract: A fuel injection system for a two-stroke cycle engine comprising an air manifold; a throttle valve; a fuel injector; a fuel supply system including a fuel pump; a battery voltage sensor; an air temperature sensor; an engine speed sensor; a timing sensor; a barometric pressure sensor; a throttle position sensor; a first data processor for receiving and processing sensing signals for determining fuel injector duration and timing and fuel pump operating speed; a first data processor temperature sensor for sensing the relative temperature of certain electronic components in the first data processor; a heater operatively associated with the first data processor electronic components for selectively heating the electronic components; and a second data processor operable independently of the first data processor for receiving an electronic component temperature sensing signal and for generating a control signal to the heater responsive thereto for heating the components when the temperature thereof is below a predet

Abstract: An electrical system for an engine of the type utilized to power an outboard motor is disclosed. The engine has a body with a crankshaft rotating therein. At least one fuel injector supplies fuel to the engine for combustion. The electrical system includes an electronic engine control unit for controlling at least the fuel injector based upon one or more sensed conditions. The electrical system also includes at least one sensor for providing data regarding one or more conditions. Preferably, at least an air pressure and intake air temperature sensor are provided. The sensors are mounted to a portion of the engine body adjacent the crankshaft, preferably via a vibration isolated bracket, for improving sensor accuracy and reliability.

Abstract: A number of embodiments of multi cylinder engines having direct cylinder injection wherein the fuel injector is positioned so as to be shrouded by the piston during at least a portion of its stroke. This permits the use of less expensive and lower pressure fuel injection nozzles. The spray pattern of the injector is chosen so that some fuel is sprayed toward the spark plug to provide stratification, but the major portion is directed toward the head of the piston so to as insure a homogeneous mixture when operating at high speed, high load conditions. All of fuel injectors are on the same side of the cylinder block and served by the same fuel rail.

Abstract: A cross-scavenged, two-cycle internal combustion engine has a low-pressure, cylinder wall fuel injection system that is practical for multi-cylinder marine engines. It also reduces the amount of unburned hydrocarbons in exhaust emissions when compared to a conventional carbureted two-cycle, cross-scavenged engine. The fuel injectors are mounted through the cylinder walls so that the fuel spray contacts a deflector on the piston crown. The fuel vaporizes upon contact, and scavenging air flow from the deflector towards the spark plug electrode convects the vaporized fuel towards the spark plug electrode, thereby reducing the likelihood of short circuiting of unburned fuel through the exhaust port before the exhaust port closes and compression begins. All fuel is injected into the piston cavity before the exhaust port closes.

Abstract: A number of embodiments of engines having direct cylinder injection wherein the fuel injector is positioned so as to be shrouded by the piston during at least a portion of its stroke. This permits the use of less expensive and lower pressure fuel injection nozzles. The spray pattern of the injector is chosen so that some fuel is sprayed toward the spark plug to provide stratification, but the major portion is directed toward the head of the piston so to as insure a homogeneous mixture when operating at high speed, high load conditions.

Abstract: A two-cycle internal combustion engine control method and system wherein economy of fuel consumption and emission control is achieved by skipping fuel injection for a number of cycles dependent upon a decrease in the engine speed and load below a predetermined value. When fuel injection is skipped, the duration of fuel injection is increased. The escape of unburned fuel from the exhaust port is achieved when the fuel injection amount is increased by advancing the timing of the fuel injection and by retarding the opening of the exhaust port.

Abstract: A loop-scavenged, two-cycle internal combustion engine has a low-pressure, cylinder wall fuel injection system that is practical for multi-cylinder marine engines and also reduces the amount of unburned hydrocarbons in exhaust emissions when compared to conventional carbureted two-cycle engines. The fuel injectors are mounted through the cylinder wall so that fuel spray contacts the piston crown underneath a zone in which incoming air flow through the transfer ports converges. The converging air flow helps to convect vaporized fuel from the piston crown upwards towards the spark plug electrode in the combustion chamber and away from the exhaust port, thereby reducing the likelihood of short circuiting unburned fuel through the exhaust port before the exhaust port closes and compression begins. All fuel is injected into the piston cavity before the exhaust port closes.

Abstract: The present invention relates to a two-stroke internal-combustion engine depollution process including a separate and deferred delivery of fuel in relation to the air used to scavenge the burned gases, and having an advanced ignition delay with respect to optimal advanced ignition. According to the invention, the delay is such that it allows the exhaust gas temperature to increase and to create a post-oxidation of the unburned hydrocarbons contained in the exhaust gases, the post-oxidation sparing the use of a specific catalyst at the exhaust. Preferably, the delay is achieved in a stabilized-speed operating range of the engine.

Abstract: A fuel pump for a two-stroke internal combustion engines, having a pump chamber with an inlet valve for connecting to a fuel delivery pump. An outlet valve for connecting to an injection nozzle of the engine, and an axially driven pump piston which defines the pump chamber. For the purposes of a simple structural embodiment for reasonably priced manufacture and flexible fuel metering, a stop is provided, which defines the intake stroke of the pump piston and whose relative position to the bottom dead center of the pump piston can be controlled as a function of operating parameters of the engine.

Abstract: An improved method of operating a direct cylinder-injected engine wherein adequate fuel and scavenging can be achieved at mid and high-mid range by injecting the fuel in two increments. Various control strategies are disclosed, and they all particularly lend themselves for use with two-cycle crankcase compression engines.

Abstract: A number of embodiments of engines having direct cylinder injection wherein the fuel injector is positioned so as to be shrouded by the piston during at least a portion of its stroke. This permits the use of less expensive and lower pressure fuel injection nozzles. The spray pattern of the injector is chosen so that some fuel is sprayed toward the spark plug to provide stratification, but the major portion is directed toward the head of the piston so to as insure a homogeneous mixture when operating at high speed, high load conditions. In order to improve scavenging under difficult running conditions injection may be skipped for one or more cycles to purge the cylinder of exhaust gasses before another injection occurs.

Abstract: A crankcase fuel injection system includes a diaphragm type fuel pump, a crankcase fuel injector assembly, and a main air inlet assembly. Engine crankcase pulses generated by the up and down movements of the piston are utilized by the fuel pump to replenish the fuel mixture in a fuel mixture injector chamber of the fuel injector assembly. The air mass entering the crankcase upon the upstroke of the piston is controlled within the main air inlet assembly by a throttle valve and metered across a main air venturi. The venturi signal at the main air venturi is amplified by a booster venturi. The amplified venturi signal is applied to a middle chamber formed between the two diaphragms of the compound diaphragm assembly which serves as the injector pump mechanism. The force acting upon the diaphragm assembly due to the amplified venturi signal is further amplified due to the area relationships of the two diaphragms.

Abstract: A two-cycle, direct injection, internal combustion engine provides improved performance by using a portion of energy produced by the production process to heat the engine. The engine includes a plurality of direct fuel injected cylinders and a fuel injection control system. The control system includes a sensory system which detects several operating parameters of the engine, such as, engine speed and intake air flow. An electronic control unit receives input signals from the sensory system and determines the operational condition of the engine. Based on the determined operational condition of the engine, the electronic control unit controls throttle opening degree, fuel injection amounts and timing, and ignition timing. At operating conditions below a preselected engine speed/load condition, the electronic control unit maintains a generally constant throttle opening and fuel injection amount to produce a desired air/fuel ratio.

Abstract: An improved fuel delivery system, method and apparatus providing a hybrid carburetor and direct fuel injection system, utilizing the best of each for different engine operational modes to thereby meet emission requirements for small hand-held two-cycle engines using standard two-stroke gasoline and oil premix fuel. A diaphragm carburetor and associated diaphragm fuel pump operates alone to supply a proper A/F idle mixture sufficient only for engine power at start-up idle and off idle (light load). This engine aspiration carburetor fuel delivery system is operated continuously, and then at part (off idle-light load) and wide open throttle (W.O.T) the same is combined with operation of a direct cylinder fuel injection system, using a second stage pressure boost peristaltic type pump and fuel injector nozzle, that is engine self-regulated and driven to operate only at part-throttle and W.O.T. to thereby supply most of the engine fuel demand in these operational ranges.

Abstract: A four-cycle internal combustion engine wherein the piston connecting rod crankshaft and crankcase chamber are formed so that the crankcase chamber acts as compressor. An induction system supplies atmospheric air to the crankcase chamber and a pressure conduit supplies air from the crankcase chamber to the engine intake valve. A plenum chamber is disposed within this pressure conduit and pressure control is possible by bypassing air form the plenum chamber to the atmospheric air inlet. A throttle valve is positioned downstream of the plenum chamber so as to improve engine braking and charge forming systems are disclosed that permit a compact assembly and good response under all engine running conditions.

Abstract: A method of operating an internal combustion engine comprising retarding the ignition of a gas/fuel mixture within at least one cylinder of the engine to after top dead center (ATDC) in respect of the combustion cycle of said at least one cylinder of the engine. While the ignition is so retarded, the fuelling rate of said at least one cylinder is increased to a level higher than that required when the engine is operating normally.

Abstract: The invention relates to an internal combustion engine for a portable handheld work apparatus such as a motor-driven chain saw or the like. The internal combustion engine includes a cylinder defining a combustion chamber and having an inlet passage for conducting a fuel mixture into the combustion chamber. The cylinder has an annular flange formed thereon and is disposed in surrounding relationship to the inlet passage. An intake pipe defines a longitudinal axis and has an end section. The end section and the annular flange are axially inserted one into the other in overlapping relationship to each other. The annular flange and the end section conjointly define an annular space therebetween radially of the longitudinal axis and a seal is clamped between the annular flange and the end section in the annular space.

Abstract: An internal combustion engine of either two-cycle or four-cycle construction including a block having at least one cylinder bore therein having sidewalls carrying a liner of a structural fiber reinforced ceramic matrix composite material disposed in sealed fiber reinforced sliding relationship within the cylinder bore, and a cylinder head sealing atop end of the cylinder bore to form a closed combustion chamber in combination with the piston. The cylinder head also has the structural fiber reinforced ceramic matrix composite material disposed on an inner surface thereof facing the combustion chamber. The preferred engine is a two-cycle engine having an externally scavenged intake system and an oil sump lubricating system thereby eliminating the need to separately mix or inject lubricating oil. Higher operating temperatures and closer tolerances allow higher fuel efficiency and less pollutant production.

Abstract: An engine control arrangement including a fuel injector and an engine stop for disabling the running for the engine. In order to facilitate restarting, the fuel injector is permitted to continue to discharge fuel for a time period after the engine stop control is initiated.

Abstract: A fuel injection apparatus of the invention for a two-stroke engine including a fuel injection with an adjusting device, which via a pulsating pressure line is supplied with the pulsating internal pressure and inner chamber of a crankcase of the two-stroke engine, so as to meter the supply quantity of the fuel injection pump as a function of the internal pressure in such a way that exhaust emissions and fuel consumption of the two-stroke engine are reduced by means of a supply quantity optimally adapted to the combustion. The fuel injection apparatus according to the invention is intended for use in two-stroke engines.

Abstract: An engine control system that is configured to be attached to the intake port or intake manifold of a reciprocating engine. The system can be designed to allow installation as original equipment or as a retrofit unit. In either case, the system provides the engine with a dual ignition and electronically controlled fuel-injection. The system includes a master control unit (MCU) that utilizes a firmware operated microprocessor. The MCU is connected to a plurality of sensors that sense critical system parameters that determine the engine settings. All system parameters are user-controlled by three system command switches that are located on a control display unit (CDU). The CDU is attached to the MCU by an electrical cable and is positioned on the vehicle to provide easy accessibility.

Abstract: A two-cycle crankcase compression direct injected internal combustion engine having a combustion chamber formed by a recess in the cylinder head in which a gap of the spark plug extends. The direct fuel injector sprays into this recess and has a first nozzle port that is directed toward the spark plug gap and at least two other nozzle ports that are directed into the recess but above the head of the piston. This achieves good stratification. The timing of the injection is such at least under low load and low speed conditions that the fuel patch will reach the spark plug at about the time it fires. A staged automatically operated throttle valve system is provided for insuring excess air to aid in the stratification and permit lean burn running.

Abstract: The invention is directed to a fuel pump for an internal combustion engine such as a two-stroke engine in a portable handheld work apparatus such as a motor-driven chain saw or the like. A pump chamber is connected via a suction valve to a fuel feed and via a pressure valve to a pressure line. A pump membrane delimits the pump chamber and is driven by the fluctuating crankcase pressure of the engine which is present in the work chamber. Pump operation free of disturbances over a wide rpm range is attained with the suction valve to the pump chamber being configured essentially as a valve having the shape of a part circle, The pressure valve is disposed approximately at the center of the suction valve and delimits the pump chamber in the stroke direction of the pump membrane.

Abstract: The invention relates to a method for controlling a two-stroke internal-combustion engine with fuel injection in the low load range, in which the fuel supply to the combustion space is interrupted for a number of working strokes stored in a characteristic diagram which is a function of operating parameters. In this case, the stored characteristic diagram is adaptively corrected continuously by means of parameters which characterize the readiness to ignite or the ignition behavior of the internal-combustion engine.

Abstract: A fuel injection system that includes an injector having a pintle movable within a housing for selectively opening and closing communication between inlet and outlet ports in the housing. The inlet port is connected to a source of fuel under pressure, while the outlet port is connected to a nozzle for delivering fuel under pressure to the engine. A section of magnetic material is coupled to the pintle, and a permanent magnet is mounted on the engine flywheel, such that magnetic forces imparted as the permanent magnet moves therepast moves the pintle against a spring to open communication between the inlet and outlet ports, and thereby deliver fuel under pressure from the source to the nozzle. A cam mechanism is rotatably positioned within the pintle housing and operatively coupled to the pintle for adjustably varying stroke of the pintle within the housing, and thereby varying time duration during which the injector opens communication between the fuel source and the nozzle.

Abstract: A closed loop fuel supply system for operating engines in all possible attitudes in which fuel is delivered by a vacuum pump responsive to the vacuum level in the crankcase of the engine and in which the vacuum driving the pump is modulated in response to the pressure of fuel being delivered to the fuel supply system so that the amount of fuel delivered for combustion purposes is equal to the requirements of the engine without any excess. In another embodiment, the delivery of pulsating fuel is dampened to obtain a uniform fuel delivery and distribution to the combustion chamber is under the control of three shutoff valves operating throughout the speed range of the engine. In each embodiment fuel is conserved and a fuel return line is not required.

Abstract: Embodiments of two-cycle crankcase compression direct injected internal combustion engines that permit good firing and effective stratification, particularly at low speed, low load conditions. The engine defines a combustion chamber having a recess with a projection extending into the center of the recess and against which fuel is injected by a fuel injector as the piston approaches top dead center at idle. The spark plug firing is initiated prior to completion of the fuel injection. A specific configuration and orientation for the fuel injector nozzle in relation to the projection size and cylinder bore size is established so as to insure that at least 50% of the fuel injected at low and idle speed conditions will impinge upon the projection.

Abstract: A fuel injection and control system for a V-type, two cycle, crankcase compression, internal combustion engine. The fuel injection system includes fuel injectors positioned in the valley of the engine and which are supplied with fuel under pressure from a fuel tank through a line in which a fuel filter and fuel pump are positioned. The fuel pump and fuel filter are disposed at one end of the engine and the amount of pressure supplied to the fuel injectors is controlled by a pressure regulator that regulates pressure by bypassing excess fuel back to the fuel filter upstream of the filter element. A throttle control and throttle position sensor are disposed at the opposite end of the engine and exhaust control valves are provided outside of the valley of the "V" of the engine.

Abstract: The invention is directed to a fuel-injection arrangement for a two-stroke engine in a portable handheld work apparatus such as a motor-driven chain saw or the like. Fuel is drawn by suction from a fuel tank by a fuel-feed pump and is made available at the suction connection of an injection pump. The injection pump has a pressure connection which is connected to an injection line through which the engine is supplied with fuel. A rapid start of a two-stroke engine provided with this fuel-injection arrangement is achieved by providing a bypass line which conducts fuel and bypasses the injection pump. A switchable flow valve is mounted in the bypass line. The bypass line opens directly into the intake channel conducting combustion air to the engine so that even without the pump action of the injection pump, adequate fuel is made available to the engine for starting the same.

Abstract: The invention is directed to a fuel-injection arrangement for a two-stroke engine in a motor-driven chain saw. An injection pump is mounted in a base housing with the injection pump including a pump piston axially displaceable in a pump cylinder. The pump piston delimits a pump chamber. The pump chamber is connected via a suction valve to a fuel tank. The fuel drawn by suction is pumped by the pump piston via a pressure valve, an injection line and an injection valve to the engine. For driving the pump piston, the latter is connected at one end to a membrane via a membrane plate. The membrane delimits a work chamber charged with fluctuating crankcase pressure. A simple assembly is provided by arranging the pump chamber, the suction valve and the pressure valve in a common valve housing which, in turn, is seated in the base housing of the injection pump in a seal-tight manner. The injection line is connected directly to the valve housing.

Abstract: A closed loop fuel supply system for operating engines in all possible attitudes in which fuel is delivered by a vacuum pump responsive to the vacuum level in the crank case of the engine and in which the vacuum driving the pump is modulated in response to the pressure of fuel being delivered to the fuel supply system so that the amount of fuel delivered for combustion purposes is equal to the requirements of the engine without any excess so that a fuel return line is not required.

Abstract: A fuel injection controlling device for a two-cycle engine comprising an air manifold; a throttle valve; a fuel injector; a fuel supply system including a fuel pump; a battery voltage sensor; an air temperature sensor; an engine speed sensor; a timing sensor; a barometric pressure sensor; a throttle position sensor; a first data processor for receiving and processing sensing signals for determining fuel injector duration and timing and fuel pump operating speed; a first data processor temperature sensor for sensing the relative temperature of certain electronic components in the first data processor; a heater operatively associated with the first data processor electronic components for selectively heating the electronic components; and a second data processor operable independently of the first data processor for receiving an electronic component temperature sensing signal and for generating a control signal to the heater responsive thereto for heating the components when the temperature thereof is below a p