Abstract: An electrically driven type low-pressure fuel pump whose flow rate can be set draws fuel from a fuel tank and discharges it at a prescribed pressure commonly to a low-pressure fuel supply system including intake manifold injectors and a low-pressure delivery pipe and to a high-pressure fuel supply system including in-cylinder injectors, a high-pressure delivery pipe and a high-pressure fuel pump. The discharge flow rate of the low-pressure fuel pump is set based on required supply quantities to the low-pressure fuel supply system and to the high-pressure fuel supply system obtained according to the engine operation conditions. The discharge quantity of the fuel pump in the internal combustion engine can be set as appropriate, and thus, deterioration in fuel efficiency due to excessive flow rate setting and operation failure due to insufficient fuel supply can be prevented, whereby reliability is improved.

Abstract: An intake structure for internal combustion engine includes an intake passage which is communicated with a combustion chamber of the internal combustion engine and through which air to be supplied to the combustion chamber flows; and a valve which is provided in the intake passage and which controls the airflow in the intake passage. The intake passage has a recess which is formed in the inner wall face of the intake passage and in which the valve is arranged; and a groove that is connected to the recess, at a substantially center position of the recess in a width direction of the recess, and that extends from the recess toward the downstream side of the intake passage.

Abstract: An engine ECU executes a program including the steps of: detecting an accelerator position; calculating a load factor KL of an engine based on the accelerator position or the like; when the engine is in a high load region, raising a pressure of fuel supplied to an in-cylinder injector and increasing a degree of opening of a throttle valve and/or increasing a lift amount of an intake valve; and when the engine is not in the high load region, lowering the pressure of the fuel supplied to the in-cylinder injector and decreasing the degree of opening of the throttle valve and/or decreasing the lift amount of the intake valve.

Abstract: An intake structure for internal combustion engine includes an intake passage which is communicated with a combustion chamber of the internal combustion engine and through which air to be supplied to the combustion chamber flows; and a valve which is provided in the intake passage and which controls the airflow in the intake passage. The intake passage has a recess which is formed in the inner wall face of the intake passage and in which the valve is arranged; and a groove that is connected to the recess, at a substantially center position of the recess in a width direction of the recess, and that extends from the recess toward the downstream side of the intake passage.

Abstract: Leakage of a combustion gas is prevented by installing a seal ring (10) in an annular groove (51) provided in the outer peripheral surface of a fuel injection valve (5). Further, a combustion gas leaked from the seal ring (10) is sealed in by providing a seal washer (11) more on the rear end side of the fuel injection valve than the seal ring (10). Thus a combustion gas seal for an injection valve is provided, and the combustion gas seal is capable of exhibiting excellent sealing ability for a long term with a simple structure.

Abstract: A dual-injector fuel injection engine includes a cylinder block, a cylinder head, an intake port, an intake manifold, a surge tank, an in-cylinder injector, an intake pipe injector, and first and second delivery pipes. The in-cylinder injector is positioned below the intake port, when seen from an axial direction of a crank shaft, and attached to the cylinder head. The intake pipe injector and the second delivery pipe are supported above the intake port, when seen from the axial direction of the crank shaft, by the intake manifold to be close to the intake port.

Abstract: An engine ECU executes a program including the steps of: selecting a map for a warm state or a map for a cold state based on an engine coolant temperature after an engine is started and rapid catalyst warm-up ends; calculating DI ratio r; calculating when to inject fuel from an intake manifold injector as time in synchronization with air intake if a load factor is equal to or greater than a threshold value and fuel is injected from injectors at a ratio predetermined therebetween; and otherwise calculating when to inject fuel from the intake manifold injector as during a period in which an intake valve is closed.

Abstract: An engine ECU executes a program including the step of detecting an engine coolant temperature (THW), the step of selecting a map for a warm state as the map for calculating a fuel injection ratio (or a DI ratio) (r) when the engine coolant temperature (THW) is equal to or higher than a temperature threshold value (THW(TH)), the step of selecting a map for a cold state as the map for calculating the fuel injection ratio (or the DI ratio) (r) when the engine coolant temperature (THW) is lower than the temperature threshold value (THW(TH)), and the step of calculating the fuel injection ratio between the in-cylinder injector and the-intake manifold injector (or the DI ratio) (r) based on the engine speed, load factor, and the selected map.

Abstract: An injection controller for an internal combustion engine that suppresses the accumulation of deposits on a nozzle hole of a direct injection valve. The injection controller includes the direct injection valve, which injects fuel into a cylinder, and an intake passage injection valve, which injects fuel into an intake passage. An ECU, which is connected to the direct injection and intake passage injection valves, executes a first fuel injection mode for injecting fuel with the direct injection valve and a second fuel injection mode for injecting fuel with the intake passage injection valve. The ECU switches fuel injection modes from the second fuel injection mode to the first fuel injection mode for a predetermined period when fuel is to be injected in the second fuel injection mode.

Abstract: An engine ECU executes a program including the steps of: selecting a map for a warm state or a map for a cold state based on an engine coolant temperature after an engine is started and rapid catalyst warm-up ends; calculating DI ratio r; calculating when to inject fuel from an intake manifold injector as time in synchronization with air intake if a load factor is equal to or greater than a threshold value and fuel is injected from injectors at a ratio predetermined therebetween; and otherwise calculating when to inject fuel from the intake manifold injector as during a period in which an intake valve is closed.

Abstract: An engine ECU executes a program including the steps of: detecting an accelerator position; calculating a load factor KL of an engine based on the accelerator position or the like; when the engine is in a high load region, raising a pressure of fuel supplied to an in-cylinder injector and increasing a degree of opening of a throttle valve and/or increasing a lift amount of an intake valve; and when the engine is not in the high load region, lowering the pressure of the fuel supplied to the in-cylinder injector and decreasing the degree of opening of the throttle valve and/or decreasing the lift amount of the intake valve.

Abstract: A relationship between an inner diameter A of a sac volume and a distance from a central axis of the sac volume is set to satisfy a condition of 1?A/2B?20. In this way, fuel, which flows from the sac volume into each injection hole, will be injected from the injection hole without being spaced from a wall surface of a valve body, which form the injection hole. Thus, it is possible to limit adhesion of a foreign substance to a wall surface of each injection hole. Furthermore, even if the foreign substance is adhered to the wall surface of the injection hole, the foreign substance can be removed by the fuel, which flows through the injection hole.

Abstract: A dual-injector fuel injection engine includes a cylinder block, a cylinder head, an intake port, an intake manifold, a surge tank, an in-cylinder injector, an intake pipe injector, and first and second delivery pipes. The in-cylinder injector is positioned below the intake port, when seen from an axial direction of a crank shaft, and attached to the cylinder head. The intake pipe injector and the second delivery pipe are supported above the intake port, when seen from the axial direction of the crank shaft, by the intake manifold to be close to the intake port.

Abstract: Fuel pipes guide fuel from a fuel tank provided in a rear area of the vehicle to a low-pressure fuel supply system and a high-pressure fuel supply system, respectively, for injecting the fuel to an engine provided in a front area of the vehicle. A branch point between the fuel pipes is arranged in the vicinity of the fuel tank to secure a long pipe length between the low-pressure fuel supply system and the high-pressure fuel supply system. This can suppress variation in fuel pressure at the low-pressure fuel supply system attributable to the fuel that is discharged from the high-pressure fuel pump within the high-pressure fuel supply system back to the fuel pipe.

Abstract: An electrically driven type low-pressure fuel pump whose flow rate can be set draws fuel from a fuel tank and discharges it at a prescribed pressure commonly to a low-pressure fuel supply system including intake manifold injectors and a low-pressure delivery pipe and to a high-pressure fuel supply system including in-cylinder injectors, a high-pressure delivery pipe and a high-pressure fuel pump. The discharge flow rate of the low-pressure fuel pump is set based on required supply quantities to the low-pressure fuel supply system and to the high-pressure fuel supply system obtained according to the engine operation conditions. The discharge quantity of the fuel pump in the internal combustion engine can be set as appropriate, and thus, deterioration in fuel efficiency due to excessive flow rate setting and operation failure due to insufficient fuel supply can be prevented, whereby reliability is improved.

Abstract: An engine ECU executes a program including the step of detecting an engine coolant temperature (THW), the step of selecting a map for a warm state as the map for calculating a fuel injection ratio (or a DI ratio) (r) when the engine coolant temperature (THW) is equal to or higher than a temperature threshold value (THW(TH)), the step of selecting a map for a cold state as the map for calculating the fuel injection ratio (or the DI ratio) (r) when the engine coolant temperature (THW) is lower than the temperature threshold value (THW(TH)), and the step of calculating the fuel injection ratio between the in-cylinder injector and the-intake manifold injector (or the DI ratio) (r) based on the engine speed, load factor, and the selected map.

Abstract: The invention relates to a combustion gas seal for injectors and to a seal structure disposed therewith, for preventing leakage of combustion gas in a state in which an injector is mounted to an engine head. And, the number of parts is reduced, vibration and noise are reduced, and sealing performance is improved. A tapered surface, in which an clearance between the tapered surface and an inner peripheral surface of a mounting hole of the engine head narrows from an engine bore side towards an atmospheric side, is disposed at a groove bottom of an attachment groove of the injector, and an abutment portion that abuts against the tapered surface is disposed at the combustion gas seal for injectors.

Abstract: An injection controller for an internal combustion engine that suppresses the accumulation of deposits on a nozzle hole of a direct injection valve. The injection controller includes the direct injection valve, which injects fuel into a cylinder, and an intake passage injection valve, which injects fuel into an intake passage. An ECU, which is connected to the direct injection and intake passage injection valves, executes a first fuel injection mode for injecting fuel with the direct injection valve and a second fuel injection mode for injecting fuel with the intake passage injection valve. The ECU switches fuel injection modes from the second fuel injection mode to the first fuel injection mode for a predetermined period when fuel is to be injected in the second fuel injection mode.

Abstract: The invention relates to a combustion gas seal for injectors and to a seal structure disposed therewith, for preventing leakage of combustion gas in a state in which an injector is mounted to an engine head. And, the number of parts is reduced, vibration and noise are reduced, and sealing performance is improved. A tapered surface, in which an clearance between the tapered surface and an inner peripheral surface of a mounting hole of the engine head narrows from an engine bore side towards an atmospheric side, is disposed at a groove bottom of an attachment groove of the injector, and an abutment portion that abuts against the tapered surface is disposed at the combustion gas seal for injectors.

Abstract: A fuel injection device and method includes a main injection valve that injects a high-pressure fuel supplied to a delivery pipe into each combustion chamber of an engine, and an auxiliary fuel injection valve supplied with the high-pressure fuel from the delivery pipe. The auxiliary fuel injection valve is capable of injecting the high-pressure fuel in sucked air flowing in a surge tank when the engine is started under cold conditions. In addition, a fuel pressure can rapidly be increased in a starting phase since vapor in the delivery pipe can be discharged by temporarily opening the auxiliary fuel injection valve.