Abstract: The invention concerns a direct injection internal combustion engine comprising a camshaft and at least two cylinders (1), having in each cylinder a mobile piston (2) associated with at least to intake valves (4, 5), each located in an induction pipes (8, 9), and at least an exhaust valve (6, 7). The displacement of said valves is independent of the rotation of the camshaft and is controlled by a computer (15). The induction pipes (8, 9) are designed to produce an air velocity field inside the cylinder (1) parallel to said cylinder axis. The computer (15) controls, cylinder by cylinder, the opening and closing times of said at lent two intake valves (4, 5) to adapt the shape of the air velocity field inside the cylinder (1) to the engine power.

Abstract: To improve startability and reduce the amount of HC emission at start-up with the aid of a construction where vaporized fuel is supplied to the bypass passage that bypasses the main passage.

Abstract: The invention relates to a spark ignited internal combustion engine with at least one cylinder that accommodates a reciprocating piston, with a cylinder head that receives at least one ignition device per cylinder and in which are formed one exhaust and two intake manifolds, said exhaust manifold communicating with a combustion chamber by way of one exhaust port and said intake manifolds communicating therewith by way of intake ports, said exhaust port being controlled via an exhaust valve and said intake ports via intake valves, said exhaust port on the one hand and said intake ports on the other hand being arranged to different sides of an elevated plane of the engine that passes through the axis of the cylinder and through the axis of the crankshaft, said intake manifolds being at least in sections arranged substantially in the direction of the cylinder's axis and being formed in such a manner that a reverse tumble flow is initiated in the combustion chamber, said flow being oriented from the intake p

Abstract: A direct injection engine capable of direct injection of fuel into a combustion chamber characterized in that discharge of gas containing hazardous gas component such as HC can be reduced and fuel economy can be improved by stratified charge combustion in the operation range of low to high speeds. Spray fuel from the fuel injector is fed to the ignition plug by tumble air flow generated in the combustion chamber and formed between the fuel injector located on the side of the combustion chamber and the ignition plug installed on the top of the combustion chamber. This engine (a tumble guide direct injection engine) is configured to ensure that fuel reaches the ignition plug at the time of its ignition.

Abstract: In a method of operating a diesel internal combustion engine, wherein a homogeneous mixture is formed in the combustion space before a spontaneous ignition by means of fuel injected directly into separately supplied combustion air, which combustion air is admitted to the combustion space in a swirling flow about the longitudinal axis of the cylinder that can be adjusted as regards its swirl intensity by a control element. A control unit adjusts the swirl intensity in a manner coordinated with the injection parameters to provide a homogeneous mixture igniting at a predetermined point for highly effective engine operation with low emissions.

Abstract: An intake apparatus of a multi-cylinder internal combustion engine wherein intake ports communicating with cylinders located at opposite longitudinal ends of a cylinder head are arranged so as to be inclined in a direction toward the longitudinal center of the cylinder head to reduce the longitudinal length of an installing section of the cylinder head for the intake manifold.

Abstract: A piston for an internal combustion engine, including a piston crown having a central axis, and a piston bowl disposed in the piston crown, on which two tumble flows of air are provided. The piston bowl has a generally V-shaped contour in section taken along a vertical plane intersecting the tumble flows, on which the two tumble flows are retained at an inclined state toward a central axis of the piston crown.

Abstract: Disclosed is an Internal combustion engine comprising at least one cylinder with a reciprocating piston to provide said engine with at least one combustion chamber, said combustion chamber further comprising a delivery injector for injecting fuel directly into said combustion chamber, said engine further comprising at least one valved inlet air duct for delivering combustion air into said combustion chamber, wherein at least said inlet air duct and/or its valve is arranged to provide a low tumble inlet port to said at least one combustion chamber, said combustion chamber, in use, having low in-cylinder tumble gas motion of said combustion air and wherein said low in-cylinder tumble gas motion of said combustion air reduces over-enleanment of fuel in end gas regions of said combustion chamber.

Abstract: The present invention provides a fuel injector mounted on a side of a combustion chamber and delivers an ovalized fuel spray toward an oblong piston bowl of the chamber. The ovality of the spray is selected in relation to the oblong piston bowl and the motion of the combustion chamber air charge during the piston compression stroke to maintain the fuel charge within the piston bowl volume (including the space above the bowl) during compression and combustion of the fuel charge in the chamber. The shape of the oval spray may be adjusted as desired. In a specific embodiment, the ovality of the fuel spray indicated by the ratio of the major dimension to the minor dimension is in the range of about 2/1 to 4/1 for delivery into an oblong piston bowl with an ovality of about 1.2/1 to 1.5/1.

Abstract: In a direct injection internal combustion engine having per cylinder at least two intake valves 1 mounted side by side, at least one exhaust valve 2, a more or less coaxial ignition device 3, an injection valve 4, and a piston 5 with combustion chamber trough 6, the injection valve 4 being mounted on the intake side, improved mixture preparation and combustion characterized by low fuel consumption and low exhaust emissions are achieved by mounting,the center of the combustion chamber trough 6 in the piston 5 noticeably displaced relative to the axis of the cylinder in the direction of at least one exhaust valve 2, and are achieved in that the boundary wall 7 of the combustion chamber trough 6 extends in projection along the axis of the cylinder between the ignition device 3 and injection valve 4.

Abstract: A stratified exhaust gas re-circulation (EGR) engine uses an exhaust port per cylinder for exhausting exhaust gases and to re-circulate exhaust gas. The EGR valve may be phased from the exhaust stroke to the intake stroke. The EGR valves that control the exhaust gas re-circulation ports may be on a separate camshaft from the other valves. The EGR ports and an intake port for each of the cylinders may be helical or tangential ports that stratified the exhaust gas and the air in the cylinder. The engine may be a direct injection or a port fuel injection engine with one or more exhaust manifolds. The exhaust gas re-circulation ports may be controlled by a single flow valve or each port may have a separate flow valve. The intake ports may be controlled by a single flow valve or each intake port may have a separate flow valve.

Abstract: In a direct injection engine capable of reducing an amount of NOx discharged as much as possible, realizing EGR in a large amount, and enlarging a stable burning limit, fuel injection valves for directly injecting fuel into combustion chambers are arranged, ignition plugs are provided in the combustion chambers to face the same, intake ports for generating a tumble gas flow in the combustion chambers are provided. The intake ports are compartmented by partitions into high velocity port portions having a high flow velocity of intake air and low velocity port portions having a low flow velocity of intake air, passage valves for opening and closing the port portions are arranged near upstream ends of the low velocity port portions, and an EGR passage for introducing an EGR gas is connected to the low velocity port portions.

Abstract: A direct fuel injection engine includes a fuel injector so positioned and oriented as to produce a fuel spray whose upper segment reaches the vicinity of a spark plug by a penetrating force of the fuel spray in a low engine speed light load operating region to achieve stratified charge combustion without the aid of tumble. A tumble control valve is operated to strengthen the tumble in a combustion chamber to achieve stratified charge combustion with the aid of tumble in an engine operating region higher in engine speed and/or engine load.

Abstract: A state of combustion in a combustion chamber is controlled by stratifying an intake gas charge within the combustion chamber, so as to reduce amounts of harmful substances left in exhaust gas. A direct-injection type internal combustion engine in which a fuel is injected into the combustion chamber and which is arranged to stratify the intake gas charge within the combustion chamber (1) such that intake gases of different compositions exist in a central portion (13) of the combustion chamber including a position of the fuel injection, and in a peripheral portion of the combustion chamber, upon initiation of combustion of the fuel at a point of time near a terminal period of a compression stroke. The intake gases of different compositions may be intake gases having different concentrations of a specific component such as recirculated exhaust gas and the fuel.

Abstract: A number of combustion chamber configurations for direct injected engines wherein the fuel injectors inject at least two fuel patches in circumferentially spaced locations. This fuel is injected into a cavity arrangement formed in the head of the piston, which directs the fuel upwardly toward a pair of circumferentially spaced spark plugs so as to insure complete combustion within the combustion chamber. Embodiments having single and paired cavities in the piston head are disclosed.

Abstract: A piston for an internal combustion engine, including a piston crown having a central axis, and a piston bowl disposed in the piston crown, on which two tumble flows of air are provided. The piston bowl has a generally V-shaped contour in section taken along a vertical plane intersecting the tumble flows, on which the two tumble flows are retained at an inclined state toward a central axis of the piston crown.

Abstract: The invention concerns a direct injection internal combustion engine comprising a camshaft and at least two cylinders (1), having in each cylinder a mobile piston (2) associated with at least to intake valves (4, 5), each located in an induction pipes (8, 9), and at least an exhaust valve (6, 7). The displacement of said valves is independent of the rotation of the camshaft and is controlled by a computer (15). The induction pipes (8, 9) are designed to produce an air velocity field inside the cylinder (1) parallel to said cylinder axis. The computer (15) controls, cylinder by cylinder, the opening and closing times of said at least two intake valves (4, 5) to adapt the shape of the air velocity field inside the cylinder (1) to the engine power.

Abstract: Within each of: (1) an internal combustion engine system; (2) a transportation vehicle which incorporates the internal combustion engine system; and (3) a method for operating the internal combustion engine system, there is employed: (1) an internal combustion engine having a minimum of one combustion chamber; (2) a gas compressor absent an associated compressed gas tank, where the gas compressor is driven by a power output of the internal combustion engine; and (3) a controller programmed for providing a compressed gas charge from the gas compressor to the minimum of one combustion chamber during a portion of a compression cycle within the minimum of one combustion chamber, but not including a beginning portion of the compression cycle within the minimum of one combustion chamber. Each of the internal combustion engine system, transportation vehicle and method provides enhanced internal combustion engine performance and economy.

Abstract: For a spark ignited internal combustion engine having at least two inlet valves per cylinder each with a separate inlet passage and with a fuel injection device which injects fuel directly into the cylinder. An air charger for generating an air charge into one of the inlet passages and a connecting duct extending between the two inlet passages with a selectively opened and closed regulating device therein to apportion the flow of charge air through the separate inlet passages.

Abstract: There is provided a cylinder injection type internal combustion engine capable of performing stratified charge operation at the time of a vehicle speed of 120 km/h and/or an engine rotational speed of 3200 rpm to enhance the fuel efficiency and/or to observe the emission regulations. In the internal combustion engine, a stratum of air and/or air flow is formed between a fuel spray injected from an injection valve and the top face of a piston and/or the wall surface of a combustion chamber, and a face shape contrived to guide the air flow is formed on the top face of the piston.

Abstract: A control device in an internal combustion engine interlocking with a device to generate swirls in a combustion chamber of the internal combustion engine by providing bypass passages which allow air to bypass a throttle valve for regulating intake air flow rate of the internal combustion engine to control an output power of the internal combustion engine and allow the air to flow in from the atmosphere side to communicate with air intake ports for respective cylinders on the downstream side of the throttle valve.

Abstract: There is provided a cylinder injection type internal combustion engine capable of performing stratified charge operation at the time of a vehicle speed of 120 km/h and/or an engine rotational speed of 3200 rpm to enhance the fuel efficiency and/or to observe the emission regulations. In the internal combustion engine, a stratum of air and/or air flow is formed between a fuel spray injected from an injection valve and the top face of a piston and/or the wall surface of a combustion chamber, and a face shape contrived to guide the air flow is formed on the top face of the piston. Also, the stratified charge operation can be performed even at the time of cold start or cranking.

Abstract: An internal combustion engine with controlled ignition and direct ignition. In the internal combustion engine at least one intake duct can generate in a cylinder a flow referred to as “tumble”, at least for certain engine operating phases. Further, a fuel injector is implanted so as to emerge in the cylinder such that the fuel jet tends to be intercepted by the part of the flow circulating in the direction opposite to that of the jet which is directed towards the spark plug.

Abstract: A compression self-ignition gasoline engine includes a stratifying device stratifying gas in a combustion chamber of the engine, a fuel injector directly injecting fuel in the combustion chamber and a controller connected to the stratifying device and the fuel injector. The controller controlling the stratifying device to produce a high temperature gas layer of a high temperature gas and a low temperature gas layer of a low temperature gas in the combustion chamber. The controller further controls the fuel injector to inject the fuel to both the high temperature gas layer and the low temperature gas layer.

Abstract: There is provided a cylinder injection type internal combustion engine capable of performing stratified charge operation at the time of a vehicle speed of 120 km/h and/or an engine rotational speed of 3200 rpm to enhance the fuel efficiency and/or to observe the emission regulations. In the internal combustion engine, a stratum of air and/or air flow is formed between a fuel spray injected from an injection valve and the top face of a piston and/or the wall surface of a combustion chamber, and a face shape contrived to guide the air flow is formed on the top face of the piston. Also, the stratified charge operation can be performed even at the time of cold start or cranking.

Abstract: In a method of operating a diesel internal combustion engine, wherein a homogeneous mixture being formed in the combustion space before a spontaneous ignition by means of fuel injected directly and separately supplied combustion air, the combustion air is admitted to the combustion space in a swirling flow about the longitudinal axis of the cylinder that can be adjusted as regards its swirl intensity by a control element. A control unit adjusts the swirl intensity in a manner coordinated with the injection parameters to provide a homogeneous mixture for highly effective engine operation with low emissions.

Abstract: In a SOHC type internal combustion engine having a single camshaft, a fuel injector is provided for directly injecting a fuel into a combustion chamber, and an intake port is provided such that one end of the intake port is open at intake openings to the combustion chamber. The intake port extends toward the top face of a cylinder head between the camshaft and two intake valves, such that at least a part of the intake port passes through a region between the shortest lines connecting respective head portions of the intake valves and the camshaft.

Abstract: A method is presented for improving performance of direct injection spark ignition internal combustion engines at high load conditions by increasing the degree of homogeneity of the air-fuel mixture during the intake stroke of the engine. The improved performance is achieved by adding a deflector designed to reduce intake air impinging upon the fuel spray and deflecting it to the intake side of the combustion chamber, thus facilitating better fuel circulation throughout the combustion chamber. This method improves engine performance at high load engine operating conditions.

Abstract: A cylinder head arrangement for a direct injected internal combustion engine and particularly one having multiple valves. The cylinder head configuration is such that the injector can be positioned centrally in the combustion chamber and disposed below the overlying ports, which preferably are the inlet ports without significantly detracting from their flow area or without requiring sharp curvature or bends in their configuration that could restrict air flow.

Abstract: A combustion chamber is formed using a flat piston having a low cooling loss and therein a forward tumble is generated. A fuel spray is formed by a provision of a splitter which is provided to make off-set from a center of an injection port at a tip end of a tumble atomization system fuel injector. The fuel spray is divided into a fuel spray having a strong penetration force and a fuel spray having a small penetration force. The fuel spray having the strong penetration force is injected in a vicinity of an ignition plug. Accordingly, a fuel adhesion to the piston can be reduced and further a reduction of a discharge HC and a fuel consumption can be improved.

Abstract: In an internal combustion engine with direct fuel injection including a cylinder block containing at least one cylinder with a piston, which performs an oscillating motion in the cylinder and a cylinder head including a combustion chamber for the at least one cylinder, a total of five intake and exhaust valves with respective intake and exhaust ducts are arranged in the cylinder head in a circular array and a spark plug and an injector are arranged in a center area of the combustion chamber between the intake and exhaust valves and point towards the center of the combustion chamber.

Abstract: In a direct fuel injection-type spark ignition internal combustion engine including a spark plug and a fuel injector for injecting fuel directly into the cylinder, the engine can carry out stratified charge combustion by the fuel injection in the compression stroke and uniform charge combustion by the fuel injection in the intake stroke. The engine includes a mechanism which can make a tumbling stream formed in the cylinder in the intake stroke in the stratified charge combustion weaker than that in the uniform charge combustion.

Abstract: A stratified exhaust gas re-circulation (EGR) engine uses an exhaust port per cylinder for exhausting exhaust gases and to re-circulate exhaust gas. The EGR valve may be phased from the exhaust stroke to the intake stroke. The EGR valves that control the exhaust gas re-circulation ports may be on a separate camshaft from the other valves. The EGR ports and an intake port for each of the cylinders may be helical or tangential ports that stratified the exhaust gas and the air in the cylinder. The engine may be a direct injection or a port fuel injection engine with one or more exhaust manifolds. The exhaust gas re-circulation ports may be controlled by a single flow valve or each port may have a separate flow valve. The intake ports may be controlled by a single flow valve or each intake port may have a separate flow valve.

Abstract: An internal combustion engine includes a plurality of cylinders defining combustion chambers each having a roof provided in the cylinder head. Each roof is composed of first and second inclined roof surfaces meeting in a ridge line. Two gas intake openings terminate in respective free edges on the first roof surface and at least one gas exhaust opening terminates in a free edge on the second roof surface. Respective gas exchange valves are seatable in the gas intake and gas exhaust openings. A fuel injection nozzle and a spark plug are supported in the cylinder head in a region of the roof. The first roof surface has, adjacent the fuel injection nozzle, a shoulder covering a terminal edge of the cylinders and extending into each combustion chamber. The shoulder has a front face transverse to the nozzle axis. The free edge of the gas intake openings intersects the ridge line.

Abstract: A four-stroke reciprocating internal combustion engine that uses stratified exhaust gas recirculation to improve combustion is disclosed. The engine includes at least one combustion chamber defined by a cylinder, a reciprocating piston contained within the cylinder, and a cylinder head. Each combustion chamber is in fluid communication with at least one intake port and at least one exhaust port. At least one intake port includes an associated intake valve and an intake flow motion generating device for creating an intake fluid flow near the intake port. At least one exhaust port includes an exhaust valve that opens during the intake stroke at part load, and an exhaust flow motion generating device for creating an exhaust fluid flow near the exhaust port during the intake stroke at part load.

Abstract: In a SOHC type internal combustion engine having a single camshaft, a fuel injector is provided for directly injecting a fuel into a combustion chamber, and an intake port is provided such that one end of the intake port is open at intake openings to the combustion chamber. The intake port extends toward the top face of a cylinder head between the camshaft and two intake valves, such that at least a part of the intake port passes through a region between the shortest lines connecting respective head portions of the intake valves and the camshaft.

Abstract: A cylinder injection type lean-burn internal combustion engine is capable of executing the purging of a vapor fuel without disturbing a state of an air-fuel mixture in a combustion chamber. The vapor fuel produced in a fuel tank is guided to a purge port provided at an intake passageway of the lean-burn internal combustion engine, and subsequently supplied along an intake air swirl flow into the combustion chamber. The vapor fuel is thereby partially concentrated in any one of a combustible air-fuel mixture layer and an air layer in the combustion chamber.

Abstract: An air/fuel mixture induction system for an internal combustion engine having a pair of intake valves, an intake air/fuel mixture flow passage communicating with each valve, a primary mask surrounding a portion of the perimeter of one of the intake valves, the air/fuel mixture being directed from the intake valve over the remaining peripheral portion thereof, thereby establishing a swirl motion in the combustion chamber, a secondary bridge mask partially surrounding the other of the pair of intake valves, the secondary bridge mask having an air/fuel mixture flow controlling surface that directs the swirl motion of the air/fuel mixture in the direction of the axis of the cylinder whereby swirl motion progresses in the direction of the axis of the cylinder throughout the combustion chamber.

Abstract: A three-valve cylinder head system for a direct-injected spark-ignited (DISI) internal combustion engine. Two inlet ports are positioned in opposite quadrants of the cylinder head, with the fuel injector directing fuel spray into a third quadrant and the exhaust port being positioned in the fourth quadrant. A helicoid intake port and an axially directed intake port generate a swirl-type air flow in the piston cylinder without the aid of flow activation devices. The spark plug is positioned centrally adjacent the longitudinal axis of the cylinder bore. The piston has a bowl in its upper surface with an enlarged downstream area and a harbor area adjacent and past the spark plug which allow the swirl-type air flow to mix with the fuel spray and provide an appropriate fuel air mixture at the spark plug.

Abstract: A direct injected, internal combustion engine combustion chamber configuration that employs a shrouded arrangement for the intake valve seat so as to generate a tumble motion under at least some running conditions. This is accomplished by a shrouding of the intake valve in such a way that the flow direction effects a tumbling motion and also so that the air flow does not adversely affect the flow from the injector nozzle.

Abstract: A spark ignition internal combustion engine is described having a fuel supply system for separating the fuel into two or more continuous streams of fuel fractions having different octane ratings. The engine has an intake system that creates within each combustion chamber a stratified charge comprising at least two regions 113, 123 each containing a higher concentration of respective one of the fuel fractions. Each combustion chamber also has two spark plugs 114, 124 each located in a respective one of the stratified charge regions. The engine ignition system separately controls the spark timings of the spark plugs 114, 124 to vary the pattern of flame propagation through the stratified charge in the combustion chambers in dependence upon the engine operating conditions.

Abstract: In a cylinder head of a fuel direct injection spark ignition type internal combustion engine, there extend a pair of intake ports to a combustion chamber. The intake ports are arranged to decrease a distance therebetween as nearing the combustion chamber. An axial center line of each intake port is inclined by an angle “&thgr;” relative to an imaginary plane which includes a center line of an associated piston and is perpendicular to an axial line of an associated crankshaft. The angle “&thgr;” satisfies the inequality of “&thgr;°<&thgr;≦15°”. If desired, the imaginary plane may be replaced with another imaginary plane which includes a center line of an associated fuel injector and extends in parallel with the center line of the associated piston.

Abstract: An improved porting and cylinder head arrangement for a multi-valve overhead valve internal combustion engine. The porting arrangement in the cylinder head permits the use of two separate and relatively large intake passages beneath which a fuel injector can be conveniently positioned without obstruction of the shape or configuration of these intake passages. A separate control valve body is fixed to the cylinder head for controlling the flow through the intake passages independently of each other while providing a common intake that can be valved by a single throttle valve.

Abstract: An in-cylinder direct-injection spark-ignition engine using at least a homogeneous combustion mode and a stratified combustion mode and equipped with a pentroof combustion chamber head having first and second shallow-angled surfaces, comprises intake valves disposed in the first shallow-angled surface, exhaust valves disposed in the second shallow-angled surface. A pair of substantially straight intake ports are formed in the cylinder head. A tumble-and-swirl control valve is disposed in a first intake port of the substantially straight intake ports for adjusting the amount of intake air passing through the first intake port.

Abstract: In an internal combustion engine with at least one injection device per cylinder for direct fuel injection into a combustion chamber, the injector nozzle is located in a top surface of the combustion chamber, which is formed in the cylinder head. In order to reduce the build-up of deposits and carbon residues in the region where the injection device enters the combustion chamber, the area around the injector nozzle is configured as a flow-directing surface for a swirl and/or tumble flow.

Abstract: A direct-injection spark-ignition engine operable between a stratified charge combustion mode where fuel injection is executed on a compression stroke while introducing a vertical-vortex tumble flow to an induced air drawn into a combustion chamber through an intake port, and a homogeneous combustion mode where fuel-injection early in the intake stroke produces a homogeneous air-fuel mixture, comprises a cylinder block having a cylinder, a piston movable through a stroke in the cylinder and having a centrally-formed piston bowl cavity combustion chamber in its piston head, a cylinder head mounted on the cylinder block, a centrally-located spark plug, and a fuel injector valve provided nearby the intake valve for injecting fuel directly into the combustion chamber.

Abstract: In a cylinder injection engine which includes an injection valve disposed in the vicinity of an intake port of the engine and adapted to inject fuel into the combustion chamber, a spark plug disposed closer to the center portion of the combustion chamber than the injection valve, and a piston having a cavity formed in the top face that substantially faces the injection valve and the spark plug, the cavity is formed by smoothly connecting a curved surface located below the spark plug and a curved surface located below the injection valve via a connection curved surface. The curvature .kappa..sub.1 of the curved surface located under the injection valve and the curvature .kappa..sub.2 of the curved surface located under the spark plug satisfy a relationship .kappa..sub.1 <.kappa..sub.2.

Abstract: An internal combustion engine with spark ignition and a piston that includes a substantially U-shaped asymmetrical piston depression with a depression floor that tapers towards an edge of the piston and that changes in a continuously rising manner into a depression wall, and an expanding squeezing chamber, the arrangement being adapted to promoting a swirling rather than a turbulent flow of injected fuel.

Abstract: An internal combustion engine is furnished with a cross flow cylinder head 1 having an exhaust duct 11 which opens on a longitudinal side wall 12 and two intake ducts 10a, 10b which open on the upper cover surface 14 in a region of the cylinder head 1 on the side toward the longitudinal side wall 12. By having the intake ducts and the exhaust duct on the same longitudinal side of the internal combustion engine relative to the central vertical longitudinal plane through the internal combustion engine, the opposite longitudinal side of the internal combustion engine remains completely free for other attachments. A pair of intake valve stem openings 8a, 8b and a pair of exhaust stem valve stem openings 9a, 9b lie in parallel planes disposed at an angle to a longitudinal plane through the axis of the engine cylinder and an injection line opening 20 extends from the aforesaid opposite longitudinal side and between said planes to an injection valve mounting hole 17.

Abstract: In an internal combustion engine with spark ignition and one or more reciprocating pistons, with an ignition device positioned in a roof-shaped top face of the combustion chamber and at least one fuel delivery device for each cylinder for direct fuel delivery essentially in the direction of the ignition device, and with at least one intake port configured so as to generate a swirl movement, the piston exhibits an asymmetrically shaped piston recess whose walls are configured as arcuate flow guiding faces assisting the swirl movement of the cylinder charge. To obtain reliable ignition of the directly introduced fuel on the one hand and maximum liberty in designing the engine on the other hand, the proposal is put forward that the piston recess between opposite walls should essentially constitute an open channel of meander-shaped or S-shaped configuration in plan view, at least one end of the channel forming an inlet area into the recess, which starts at the piston rim.