Abstract: A combustion state estimating apparatus for estimating the state of combustion in an internal combustion engine includes an angular acceleration calculator that calculates a crank angle acceleration, and a combustion state estimator that estimates the state of combustion in the internal combustion engine based on the crank angle acceleration in a crank angle interval in which an average value of inertia torque caused by a reciprocating inertia mass of the internal combustion engine is substantially zero. Thus, the combustion state estimating apparatus excludes the effect that the inertia torque caused by the reciprocating inertia mass has on the angular acceleration, and therefore is able to precisely estimate the state of combustion based on the angular acceleration.

Abstract: An accumulator fuel injection system 1 comprises a PC sensor 21 for detecting a common rail pressure, a pressure limiter 22 for keeping the common rail pressure below a high limit pressure by opening its valve when the common rail pressure exceeds the high limit pressure, and an ECU 14 for controlling flow rate of fuel to be injected from an injector 13 so that the common rail pressure reaches the high limit pressure when an engine is started in a state in which an abnormality has occurred in the supply under pressure by a supply pump 12. It is possible to keep the common rail pressure within an actually used region by opening the pressure limiter after the engine is started, even in a state in which a full open abnormality has occurred at a suction flow control valve 15.

Abstract: Diesel engine fuel supply systems are provided that are preferably adapted to reduce fuel pressure loss. Preferred fuel supply systems comprise a fuel supply line for providing fuel from a fuel tank to a fuel injector through a prime pump and fuel filter. A first fuel return line is configured to return the residual fuel in the fuel injector to the fuel tank. A second fuel return line is configured to return the residual fuel in the fuel injector to the fuel filter. A heater heats up the fuel passing through the second fuel return line. A bypass line is suitably equipped to directly provide the fuel to the fuel injector through the fuel filter without passing through the prime pump.

Abstract: An internal combustion engine controller includes a main processor for monitoring operating parameters of an internal combustion engine and a triggering device, working together with the main processor, for an electric fuel pump of the internal combustion engine. The triggering device works together with an electric activation device and operates so that the fuel pump is triggered essentially without time delay after actuation of the activation device. The internal combustion engine controller has an electronic switching device which operates so that, during an initialization process of the main processor, it triggers the electric fuel pump independently of the main processor.

Abstract: In an engine (1) in which the fuel injection rate is controlled by a governor (11) having a construction in which the turning of a governor lever (31) connected to the control lever (16) of a fuel injection pump (12) is controlled within a fixed range by a control section (33b) installed in a limiter (32), on the side surface of the engine (1), a stopper (40) for determining the maximum fuel injection position of the limiter (32) is provided with a heat sensitive expansion member, so that the expansion of the heat sensitive expansion member with increasing temperature causes the maximum fuel injection position of the limiter (32) to move to the fuel quantity decrease side.

Abstract: A starting method of an LPI engine in a partial cool-down state wherein an engine is allowed to start with ample fuel pressure obtained in a fuel line when an LPI engine is in a partial cool-down state, thereby enabling the engine to start smoothly, and a fuel pump is driven at a maximum speed for a prescribed period of time within the scope of not generating noise even after starting of the engine has been performed, thereby enabling a stable engine operation.

Abstract: A diesel engine comprises a high-pressure pump (5) driven by an engine (E) to supply fuel in a fuel tank (2) to a common rail (3), an electric priming pump (13) provided in a fuel passage (15) extending from the fuel tank (2) to the high-pressure pump (5), and a control device (10) to control the electric priming pump (13). The control device (10) drives the electric priming pump (13) when the engine is started, if a state that the engine rotating speed (Ne) is higher than a predetermined first rotating speed (N1) and the common rail pressure (Cp) is lower than a predetermined first pressure (C1) continues for a period being equal to or more than a predetermined first period (T1). The burden on the operator is mitigated since necessity for the priming operation can be automatically judged.

Abstract: During a start, particularly during a cold start, of an internal combustion engine without additional auxiliary drive, a precisely metered fuel mass is introduced into a combustion chamber. In the case of an internal combustion engine having direct fuel injection, a rail pressure prevailing in a high-pressure accumulator is frequently only insufficiently built up during a start, which has an unfavorable effect on the mixture formation. To improve the start performance of the internal combustion engine, the injection pressure available in the high-pressure accumulator is monitored during the start, and fuel from the high-pressure accumulator is first injected into the at least one combustion chamber when the injection pressure has reached or exceeded a specifiable threshold value. This ensures that the rail pressure is high enough, in order to inject a sufficient quantity of fuel into the combustion chamber so that an ignitable air/fuel mixture is formed.

Abstract: A cold start fuel control system is disclosed for use with an internal combustion engine having a plurality of combustion chambers, a source of fuel and an intake manifold having an inlet and an outlet port connected to each combustion chamber. The system includes a cold start fuel injector assembly having an inlet and an outlet to provide a vapor fuel charge during a cold start engine condition. The cold start fuel injector assembly inlet is fluidly connected to the source of fuel. An auxiliary intake manifold has an internal chamber and the cold start fuel injector assembly outlet is fluidly connected to the auxiliary intake manifold chamber. The auxiliary intake manifold chamber is then fluidly connected through a control orifice to each of the combustion chambers at a position downstream from the inlet of the primary intake manifold.

Abstract: A start assister (10) of a fuel injection pump, comprising a piston (46) inlayed into a housing (H), an upper chamber (49) formed over the piston (46), lower chamber (48) formed under the piston (46), wherein a sub port (42) is opened and closed by sliding of the piston (46), and a fuel injection timing is advanced by closing the sub port (42). A thermo-element (61) for sliding the piston is arranged on one side of the piston (46) in sliding direction. A telescopic pin (61a) of the thermo-element (61) is arranged in a low-pressure chamber (50) divided into the upper chamber and the lower chamber, and a connection pin (62) is interposed between the telescopic pin (61a) and the piston (46).

Abstract: A fuel pump (14) pumps fuel in a method for operating an internal combustion engine (10). The fuel pump (14) is connected at its input end to a fuel tank (12). Fuel reaches at least one combustion chamber (22) of the engine (10) via at least one fuel-injection device (16). In order to be able to inject fuel with still greater accuracy into the combustion chamber (22) of the engine (10), the fuel quantity which arrives in the combustion chamber (22) is determined from the signal of a through-flow measuring device (18).

Abstract: A high pressure piston pump includes a housing having a low pressure fuel inlet and a high pressure fuel outlet; at least two pistons disposed in the housing; a driveshaft for supplying power to drive the at least two pistons; and a bypass valve fluidly connected to at least one of the at least two pistons to deactivate the at least one piston. A method of varying the flow output of a high pressure piston pump having at least two pistons includes deactivating at least one of the two pistons by directing fluid displaced by the at least one piston to a bypass valve.

Abstract: A method and a device for controlling an internal combustion engine having a central control unit and a peripheral control unit are described. The central control unit transmits request signals to the peripheral control unit. At least two load circuits receive control signals from the peripheral control unit. The peripheral control unit checks the request signals and/or additional signals for plausibility.

Abstract: A fuel injection and ignition system for an internal combustion engine adapted to apply a power source voltage to an injector, an ignition circuit, an electronic control unit and a fuel pump from a single voltage regulating power source circuit having as a power source a generator driven by the internal combustion engine through a power line and to control a drive current of the fuel pump in a pulse width modulating mode (PWM mode) so as to keep the power line voltage at a value higher than a reference voltage, which is set slightly higher than a voltage corresponding to one higher among the minimum operation voltages for the injector and that for the ignition circuit, in the course where the internal combustion engine starts.

Abstract: During a start, particularly during a cold start, of an internal combustion engine without additional auxiliary drive, a precisely metered fuel mass is introduced into a combustion chamber. In the case of an internal combustion engine having direct fuel injection, a rail pressure prevailing in a high-pressure accumulator is frequently only insufficiently built up during a start, which has an unfavorable effect on the mixture formation. To improve the start performance of the internal combustion engine, the injection pressure available in the high-pressure accumulator is monitored during the start, and fuel from the high-pressure accumulator is first injected into the at least one combustion chamber when the injection pressure has reached or exceeded a specifiable threshold value. This ensures that the rail pressure is high enough, in order to inject a sufficient quantity of fuel into the combustion chamber so that an ignitable air/fuel mixture is formed.

Abstract: A fuel delivery unit for an internal combustion engine including a housing, which includes a timing unit for shifting the point of injection of fuel into the combustion chambers of the internal combustion engine. An injection timing piston is accommodated in the timing unit, which is displaceably mounted in the timing unit and which encloses a trailing piston displaceably relative thereto. The timing unit contains a pressure chamber which may be pressurized/depressurized via an actuator, a cold start accelerator piston being movable via the pressure chamber, acting upon both the trailing piston via a spring element and, together with a spring-sleeve combination, influencing the injection timing piston.

Abstract: A fuel system serves to supply fuel to an internal combustion engine includes a reservoir and a first fuel pump whose input is connected to the reservoir and a second fuel pump whose input is connected to the first fuel pump. At least one injection valve is connected to the second fuel pump and can supply fuel at least indirectly to a combustion chamber. A leakage line is provided between the second fuel pump and the reservoir. In order to permit a reliable hot start of the engine with a simultaneously low strain on the components, the leakage line is provided with a valve device which has a shutoff function and a pressure relief function that are connected in parallel with each other.

Abstract: The high-pressure fuel supply system of an internal combustion engine includes a high-pressure portion for supplying fuel to a plurality of fuel injection valves, a high-pressure pump, and a low-pressure pump for supplying fuel to the high-pressure pump. Upon starting of the engine, the high-pressure fuel supply system starts fuel injection after a pressure in the high-pressure portion is raised to a preset pressure higher than a rated discharge pressure of the low-pressure pump by the high-pressure pump. In view of a fuel consumption amount consumed from the high-pressure portion through the fuel injection valve and a fuel supply amount supplied to the high-pressure portion by the high-pressure pump, the preset pressure at which the fuel injection is started is set so that first fuel injection to each cylinder of a plurality of cylinders by each of the plurality of fuel injection valves is conducted at a pressure higher than the rated discharge pressure of the low-pressure pump.

Abstract: An inlet throttle valve for supplying liquid to a high-pressure pump has a fully open start position and an operating range where flow through the valve is determined by a pressure balance of a valving member independent of the pressure of oil supplied to the inlet throttle valve. The valve includes a hydraulic stop limiting closing movement of the valving member. The valve may be used to flow low-pressure oil to a high-pressure pump for supplying high-pressure oil to HEUI injectors or other components of an internal combustion engine.

Abstract: A fuel pump draws pumps fuel from a fuel tank to a pressurizing chamber during a suction stroke, and pressurizes and sends fuel in the pressurizing chamber to a delivery pipe. A electromagnetic valve is actuated by electricity from a battery to electively connects and disconnects the fuel tank with the pressurizing chamber. An ECU determines opening and closing timing of the electromagnetic valve based on the rotation al phase of an engine. When the rotational phase of the engine is not identified, the ECU executes a duty control to cyclically repeat supplying and stopping of current to the electromagnetic valve. The ECU extends a current supplying period in each cycle of the duty control as the voltage of the power supply is lowered. As a result, the electromagnetic valve is reliably closed particularly at each pressurizing stroke, which improves the pressure increasing efficiency of fuel supplied to a fuel injection system.

Abstract: The invention relates to a method and a device for automatic starting of a diesel engine, actuation of the ignition key (1) initiating preheating (2) and turnover of the engine by the starter (3) and fuel injection (4) being triggered at the earliest when the minimum temperature of the glow plugs (2′) required for starting of the engine has been reached. The object pursued is further development of the method and device so that duration and/or energy requirement for automatic starting is/are reduced. The object is attained in that, when the ignition key (1) is actuated, the throttle valve for delivery of air to the combustion chamber is also closed and is opened again at the earliest shortly before triggering of fuel injection (4). The device comprises a suitably designed control unit (6).

Abstract: The invention relates to a method for starting a multi-cylinder internal combustion engine (1), especially of a motor vehicle. The position of a piston (2) in a cylinder (3) of the engine (1) is determined and fuel is injected into a combustion chamber (4) of that cylinder (3) whose piston (2) is disposed in a work phase. In order to make possible a start of the internal combustion engine (1) as reliable as possible without an electro-motoric starter, it is suggested that the inlet and/or outlet valves (5) of at least one cylinder (3), whose piston (2) is disposed after top dead center (TDC), is brought into a position corresponding to a work phase in advance of the starting operation.

Abstract: A method is provided for starting an internal combustion engine which includes a starter, an ignition, pressure store and injection valves for injecting fuel directly into the engine. An electrical high pressure pump is connected to an electrical fuel pump downstream thereof for pumping the fuel into the pressure store. The electrical fuel pump and the electrical high pressure pump are first switched on together with the ignition in order to generate a pressure in the pressure store adequate for the injection of the fuel. Then, the starter is switched on after a time duration after the electric fuel pump and the electrical high pressure fuel pump are switched on.

Abstract: A device including an internal combustion engine, an engine control device coupled to the internal combustion engine and manually operable to stop operation of the engine, a fuel tank coupled to the engine for providing fuel to the engine, and a fuel vent closure device communicating with the fuel tank. The fuel vent closure device is automatically and electrically operable in response to the manual operation of the engine control device to substantially seal the fuel tank when the engine is stopped, thereby substantially preventing emissions from the fuel tank. The device also preferably includes a fuel shutoff device automatically and electrically operable in response to the manual operation of the engine control device to substantially block the supply of fuel to the engine when the engine is stopped.

Abstract: A high-pressure fuel supply system of an internal combustion engine is provided which includes a high-pressure pump driven by the engine and operable with a cycle consisting of an intake stroke and a discharge stroke. The high-pressure pump includes a valve selectively placed in an open position to allow the fuel to be introduced into the pump and in a closed position to allow the fuel to be fed under pressure to a high-pressure portion located downstream of the high-pressure pump. A controller of the fuel supply system generates commands for closing the valve to the high-pressure pump during starting of the engine before the cylinders are discriminated from each other, such that a period of the generated commands is shorter than a half of the cycle of operation of the high-pressure pump during starting of the engine.

Abstract: The invention relates to a device of the build-up of pressure in supply systems (6, 11, 20, and 23) to components (19, 36) on internal combustion engines (2). The invention includes directly couples lubricant systems and pressure-generating systems (3, 8), an electric fuel pump (34), as well as a control apparatus for determining lubricant pressures. A supply module (12, 34) is provided with an independent drive (16) and supplies lubricant in the lubricant oil circuit (24) or to selected lubricating position, or fuel into a fuel supply (36). The supply module (12, 34) can optionally include a pressure converter (30).

Abstract: A fuel system for fluidly connecting a fuel tank with an engine includes a low-pressure fuel circuit connected to the fuel tank. A high-pressure fuel circuit connected to the engine is supplied with fuel by the low-pressure fuel circuit. A priming fuel circuit includes a priming fuel conduit and a priming valve. The priming fuel conduit has a first segment and a second segment. The priming valve has an inlet and an outlet. The first segment of the priming fuel circuit interconnects the low-pressure fuel circuit and the outlet of the priming valve. The second segment of the priming fuel circuit interconnects the high-pressure fuel circuit and the inlet of the priming valve. The priming valve is operable to control a flow of fluid through the priming fuel conduit to thereby selectively connect and disconnect the high-pressure fuel circuit and the low-pressure fuel circuit.

Abstract: A hydraulically activated fuel injection system uses a common rail that is maintained at relatively high pressure by a pump when the engine is running. During start-up, a volume reducer is used to pressurize the common rail until the pump can take over. A member of the volume reducer protrudes through one end of the common rail and is movable into and out of the common rail. When the ignition is activated, the member advances into the common rail causing the fluid volume to decrease and the pressure within the hydraulic system to increase, thereby allowing activation of the fuel injectors and starting the engine before the system pump is able to supply high pressure fluid to the common rail. Once the pump is able to sustain system pressure to the desired level, the member can retract to its original position.

Abstract: A method for controlling start of a compression ignition engine having a plurality of cylinders is provided without a cam sensor is provided. Each cylinder includes a respective piston reciprocally movable between respective top and bottom positions along a cylinder longitudinal axis. The method comprises proving a respective fuel delivery assembly for each cylinder. In one embodiment the method further comprises retrieving from memory a set of fuel delivery assembly firing rules and then processing the firing rules so that a firing signal is delivered to each fuel delivery assembly on every crank revolution during a cranking mode of operation. The fuel delivery assembly is arranged to be responsive to any firing signal received during an injection window leading to the top position along the longitudinal axis so as to supply fuel to each cylinder during the injection window.

Abstract: The invention relates to a method and a device for automatic starting of a diesel engine, actuation of the ignition key (1) initiating preheating (2) and turnover of the engine by the starter (3) and fuel injection (4) being triggered at the earliest when the minimum temperature of the glow plugs (2′) required for starting of the engine has been reached.

Abstract: A high-pressure fuel supply system includes an accumulator-type booster mechanism which increases the pressure in a high-pressure portion of the high-pressure fuel supply system to a preset starting pressure upon starting of an engine. The accumulator-type booster mechanism is supported on the engine body.

Abstract: Described is an apparatus for rapid pressure buildup in a motor vehicle reservoir-type injection system (common rail) supplied with fuel by a high-pressure pump, the apparatus including a piston, which defines a pressure chamber that can be enlarged counter to the force of a spring element prestressed counter to the piston, which pressure chamber communicates with the feed pump and with the device supplied with the pressure medium. A locking device acting on the piston is provided, by which the piston can be locked in a locking position, assumed as a result of the pressure, built up in the pressure chamber by the feed pump, counter to the prestressing of the spring element and can be untensed after unlocking into a position that reduces the size of the pressure chamber. By the relaxation of the spring, the system pressure is built up suddenly.

Abstract: A method of operating an internal combustion engine of a motor vehicle supplying fuel by at least one supply pump with cyclically changing supply output into a pressure storage, injecting the fuel from the pressure storage under pressure by at least one injection valve at an injection time directly into a combustion chamber of the internal combustion engine, measuring a pressure acting on the fuel, and matching cycles of a supply output of at least one supply pump and an injection time of the fuel in time relative to one another.

Abstract: A fuel injection pump has an injection adjuster whose injection adjuster piston is acted upon on one face end by a restoring spring and by a pressure controlled by a control slide. On another face end the injection adjuster piston is exposed constantly to a pressure fluid source, which furnishes an rpm-dependent pressure. The control slide is adjusted positively by a control piston actuated by a control pressure, and in the process the control piston varies the pressure, acting the one face end, in a closed first pressure chamber. The injection adjuster piston is thus free of relatively high adjusting pressures acting on the injection adjuster piston transversely to a direction of motion.

Abstract: A control mechanism functions as a dual stage controller that is alternately and independently responsive to engine oil pressure and intake manifold pressure to adjust fuel delivery by one or more unit pumps. Engine oil pressure is delivered as a control input to one end of a piston bore. Manifold air pressure acts on a diaphragm to deliver another control input which acts on a control piston disposed for reciprocation in the bore. The diaphragm and associated control rod are axially opposed to the end of the bore to which engine oil pressure is delivered. During engine start up, oil pressure is low and a spring bias moves the control piston in a direction to increase fuel delivery. During start up, the control piston position is dependent upon engine oil pressure independent of manifold air pressure. After start up, the control piston position is a function of manifold air pressure independent from engine oil pressure.

Abstract: In a fuel injection pump with a housing (10), a metering pump (18, 20) and an injection adjuster (26) for the metering pump, in which the injection adjuster has a piston (28) that is acted upon by a restoring spring (48), the starting performance of the internal combustion engine supplied by the injection pump is to be improved. To that end, a starting spring (50) is provided in addition, which acts on the piston (28) and acts counter to the restoring spring.

Abstract: In an internal combustion engine system, a fuel injection control apparatus for preventing fuel leakage with high reliability in the engine-stopped state. The apparatus includes various types of sensors (5, 6, 14, 15) for detecting operation states of an internal combustion engine (1), a fuel pump (24) and a fuel supply pipe (22) for supplying a fuel from a fuel tank (23) to the engine (1), a fuel injector (8) for injecting the fuel into the engine, an engine stoppage detecting means for detecting a stopped state of the engine (1), a fuel temperature estimating means for estimating temperature of the fuel within the fuel supply pipe (22), and a fuel pressure lowering means for lowering pressure of the fuel within the fuel supply pipe (22). The fuel pressure lowering means is designed to lower pressure of the fuel within the fuel supply pipe (22) after the stoppage of operation of the engine (1) in dependence on an estimated fuel temperature determined by the fuel temperature estimating means.

Abstract: In one aspect of the present invention, a method is disclosed for controlling the timing at which fuel is to be injected. In response to engine speed and temperature, a desired timing signal is produced. The desired timing angle represents when the start of injection is to occur in order to cause combustion at substantially Top Dead Center (TDC). The timing signal additionally accounts for a predetermined ignition delay from the time that fuel is injected to the start of combustion.

Abstract: An internal combustion engine, in particular for a motor vehicle, which is provided with a fuel pump which can deliver fuel into a pressure reservoir. A control device is provided, which is connected to the fuel pump. The delivery quantity of the fuel pump can be changed and the fuel quantity supplied to the pressure reservoir can be adjusted to a required fuel quantity by influencing the delivery quantity of the fuel pump. The control device can control the delivery quantity of the fuel pump by a program map as a function of a number of input variables during the startup of the engine.

Abstract: A fuel supply system for fuel supply of an internal combustion engine has a fuel supply container, a fuel supply unit having a pressure limiting valve providing an adjustable maximum pressure, a fuel supply conduit having a pressure regulating valve adjustable to an operational pressure for maintaining a regulated operational pressure in the fuel supply conduit, a fuel return conduit adapted to connect the internal combustion engine with the fuel supply container, and a delay valve associated with the pressure regulating valve for loading the fuel supply conduit with an initial pressure which is higher than an operational pressure.

Abstract: An outboard motor engine includes a plurality of cylinders. A fuel injector is disposed to inject a charge of fuel into an intake system. The fuel injector can form a portion of a direct injection system or a manifold injection system. The engine includes a processor that cycles each of the fuel injectors prior to energizing a fuel pump, a starter motor, or another electrical component of the outboard motor. By energizing the fuel injectors in sequence, a higher level of voltage can be applied to each fuel injector. In addition, by energizing the fuel injectors prior to energizing other electrical components, a higher level of voltage can be applied to each fuel injector.

Abstract: An apparatus for priming a diesel fuel system includes a diesel engine having a plurality of injectors. The injectors receive a supply of diesel fuel from a fuel injection pump. A fuel feed pump supplies diesel fuel to the fuel injection pump. A controller energizes said fuel feed pump during an initial operating time period. The controller then de-energizes said fuel pump during a second operating time period to prevent heat build up, noise, and battery drain. The controller then energizes said fuel feed pump during a priming time period, allowing the diesel fuel system to be primed with diesel fuel. The controller then de-energizes said fuel pump after said priming time period to prevent heat build up, noise, and battery drain.

Abstract: A system intended for pressure supply of liquid fuel to at least one combustion chamber of an internal-combustion engine, includes a tank (1) intended for pressure storage of the liquid fuel, injectors (2) for pressure injection of the fuel into at least one combustion chamber, a line (3) between the tank (1) and the (pressure) injectors (2), a pump (4) placed in the tank (1) or on the line (3), a pressure regulator (5) placed in the tank (1) or on the line (3), and a capacity (canister) (6) placed on a by-pass (7) of the line (3) towards an intake system (A) of the engine and intended for gaseous fuel storage. The fuel injection is performed directly or not into the combustion chamber(s), and a solenoid value (8) for isolating the injectors (2) in relation to the tank (1) and are provided a drain (9) for draining the injectors (2), placed on the by-pass (7), upstream from the capacity (6).

Abstract: In a high-pressure pump for an internal combustion engine, a spill valve is inhibited from being stopped frequently. If the fuel injection amount becomes smaller than a predetermined amount, a method of determination is changed so that a feedforward term for duty control increases. This makes it unlikely that the duty ratio will become equal to zero. Operation resulting from a closing motion of the spill valve occurs substantially regularly. As a result, the circumstance where operation noise is generated irregularly is avoided, and a sense of incongruity given to the driver is reduced.

Abstract: In order to reduce load placed on an engine by suppressing loss of the engine power, the fuel feeding device is arranged to comprise a check valve and a two-port connecting valve and further comprises a branch passage for connecting a portion between the check valve and a deliver side of a pumping element with a low pressure and high pressure passage so that the branch passage is opened through operation of the two-port connecting valve when amount of fuel required by the engine is small.

Abstract: A fuel system has a pump which supplies fuel under pressure to a fuel rail for distribution by fuel injectors to the cylinders of an engine. A fuel accumulator, having a volume greater than the volume of fuel required to start the engine, is disposed in fluid communication with the fuel rail to supply a charge of fuel thereto during engine start-up at a pressure level sufficient to cause fuel atomization within the cylinder. The fuel in the accumulator is stored at the ambient pressure. A spring force or a solenoid force is applied to the fuel in the accumulator such that the fuel is ejected into the fuel rail at the required pressure level. A check valve is positioned to prevent fuel flow from the fuel rail to the pump during the initial discharge from the accumulator. The accumulator is refilled by fuel from the pump during normal operation and the fuel therein is reduced to ambient pressure when the engine operation is discontinued.

Abstract: The invention concerns a relief device for a high-pressure direct-injection pump supplying petrol to an automobile vehicle engine injector manifold, the pump being supplied with fuel by a low-pressure electric fuel pump communicating with a fuel tank and the high pressure delivered being regulated by a pressure regulator, said pressure regulator taking the form of a three-way valve supplying fuel to the manifold via the fuel pump below a predetermined engine rotation speed threshold and then supplying the manifold via the top part of the injection pump when the engine speed is above the predetermined threshold.

Abstract: This accumulating fuel injection apparatus is provided with a needle valve 6 adapted to open and close an injection nozzle 11 having injection ports 14 in a lower end portion thereof, a balancing chamber 5 formed in a casing 2 so as to apply a fuel pressure to a head portion of the needle valve 6, a supply passage including a slit 10 and used for supplying a fuel from a fuel supply port 19 to the balancing chamber 5, a discharge passage 20 comprising an orifice for discharging the fuel from the balancing chamber 5, and a solenoid valve 22 adapted to open and close the discharge passage 20, the lift of a valve disc 26 of the solenoid valve 22 is controlled by a lift control means comprising a stopper 28 the position of which is controlled by a lift control mechanism 23.