Abstract: A direct fuel injection-type spark-ignition internal combustion engine is disclosed. The engine comprises a spark plug, a cavity formed on the top surface of the piston, and a fuel injection valve for injecting fuel into the cavity in nearly the flat fan shape having a relatively small thickness. An opposing side wall of the cavity opposite to the fuel injection valve, for leading the fuel to the vicinity of the spark plug, has an arcuate portion having a plurality of arcuate shapes in a plan view. The radius of arcuate shape at the both side parts of the arcuate portion in a plan view is smaller than the radius of arcuate shape at the center part of the arcuate portion in a plan view. The opposing side wall has a deflecting portion to deflect the fuel toward the inside of the cavity.

Abstract: A control system is described for optimizing the reduction of nitrogen oxides in exhaust gas produced by an internal combustion engine, especially those internal combustion engines that employ a lean air-fuel ratio. The control system employs a temperature control assembly that is capable of selectively heating the exhaust gas prior to introduction into the NOx catalyst system, thus rapidly bringing the temperature of the NOx catalyst system up to operating temperature.

Abstract: A control system for an internal combustion engine comprising a direct cylinder fuel injection valve for directly injecting the fuel into a cylinder of an internal combustion engine. The main fuel that burns in the cylinder is injected in the latter half of the compression stroke of the cylinder, and the secondary fuel which is the ineffective fuel that does not burn in the cylinder is injected in the latter half of the exhaust stroke, the main fuel and the secondary fuel being injected toward a cavity formed in the top surface of the piston. The main fuel that is injected is deflected by the cavity to form a charge of a combustible air-fuel ratio mixture around the spark plug. When the secondary fuel is injected, the exhaust valve is opening, and the fuel that is deflected is all discharged out of the cylinder through the exhaust port.

Abstract: A direct fuel injection, spark-ignition internal combustion engine wherein fuel mainly proceeds toward a spark plug side wall of a cavity along a bottom wall, is deflected by the spark plug side wall and is led to the vicinity of a spark plug. In the engine, the spark plug side wall of the cavity is provided with a deflecting portion inclined toward the inside of the cavity. A first part of the deflecting portion provided on both sides of the spark plug side wall functions to lead the fuel to the vicinity of the spark plug. A second part of the deflecting portion on the central portion of the spark plug side wall functions to lead the fuel to a region neighboring the side of the fuel injection valve from the vicinity of the spark plug.

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 stratified-charge combustion system design for direct-injection spark-ignited engines with the piston bowl in the exhaust-valve side. The air flow from the inlet valve provides a normal tumble in cylinder air flow. The fuel injector is positioned on the intake-valve side of the combustion cylinder and forms a charge stratification in the combustion chamber. With the piston bowl on the exhaust-valve side, the distance for spray penetration of the fuel from the injector is extended. The rate of fuel spray penetration in the combustion chamber is reduced by counter air flow against the fuel spray. The air-fuel mixture is moved upwardly to the area of the spark plug by the tumble air flow for ignition. The invention provides less piston bowl wall wetting which results in less soot formation and less emissions of undesirable hydrocarbons.

Abstract: A direct fuel injection-type spark-ignition internal combustion engine is disclosed. The engine comprises a spark plug, a fuel injector and a cavity formed on the top surface of the piston. The cavity has a bottom wall, a spark plug side wall and a fuel injector side wall. The fuel injector injects fuel toward the bottom wall of the cavity in stratified charge combustion. The fuel mainly proceeds toward the spark plug side wall of the cavity along the bottom wall, is deflected by the spark plug side wall and is led to the vicinity of the spark plug. In the engine, the fuel injector side wall of the cavity is provided with a deflecting portion. If a part of the injected fuel proceeds toward the fuel injector side wall along the bottom wall of the cavity, that part of the fuel is led to the vicinity of the spark plug by the deflecting portion.

Abstract: A direct fuel injection-type spark ignition internal combustion engine is disclosed. The engine comprises a spark plug arranged in the upper wall of the cylinder, a fuel injector for directly injecting fuel into the cylinder, and a cavity formed in the top surface of the piston. The cavity has a bottom wall and a spark plug side wall. Fuel injected into the cavity from the fuel injector in the latter half of the compression stroke proceeds on the bottom wall of the cavity so as to be deflected by the spark plug side wall and led to the vicinity of the spark plug. In the engine, the fuel injector injects fuel in the shape of a fan having a relatively small thickness. The cavity has guide walls for preventing fuel from excessively spreading in the direction of width of the fan shape as it proceeds on the bottom wall.

Abstract: A direct injection combustion engine includes a combustion chamber, a spark plug and a shield. The combustion chamber includes a fuel intake port, an air intake port and a spark plug insertion opening. The spark plug includes a threaded shell having a firing end, a firing electrode, a ground electrode, and an insulator core nose extending substantially beyond the firing end of the threaded shell, the spark plug being installed in the opening so that the firing electrode, the ground electrode, and the insulator core nose extend into the chamber. The shield is attached to a surface of the combustion chamber and is positioned between the fuel intake port and the spark plug insertion opening and reduces the flow of fuel from the fuel intake port to the insulator core nose, including the portion of the core nose extending into the chamber, without preventing flow of fuel directly from the fuel intake port to a spark gap defined between the firing electrode and the ground electrode.

Abstract: A number of embodiments of combustion chamber configurations for direct injected internal combustion engine. Each embodiment employs a bowl in the head of the piston which is offset to one side of the piston and the fuel injector sprays into the peripheral edge of the bowl and toward the axis of the piston. The bowl configuration is such that the injected fuel is swept upwardly toward the center of the piston and toward a downwardly-facing spark gap mounted above the piston in the cylinder head so as to ensure the presence of a stoichiometric mixture at the time of firing, regardless of the amount of fuel injected.

Abstract: A separate lubricating device for a two-stroke internal combustion engine provided with an air intake system and a controlling device includes an injector for injecting lubricating oil into a passage of the air intake system and a lubricating control device associated with the controlling device. The lubricating control device controls the timing and quantity of injection of the lubricating oil into the engine.

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: A direct cylinder injection-type spark ignition internal combustion engine is disclosed. The internal combustion engine comprises a spark plug 6, a cavity 8 formed in the top surface of the piston, and a fuel injection valve 7 for injecting fuel into said cavity in nearly the shape of a fan having a relative small thickness. A side wall 8b of the cavity opposed to the fuel injection valve for leading the fuel to the vicinity of the spark plug, has a horizontal arcuate shape which is nearly symmetrical to a first vertical plane (N1). The first vertical plane is separated away from a vertical center plane (Nc) at the center of the fuel and is nearly parallel with the vertical center plane.

Abstract: A method for operation of a direct-injection spark-ignition internal combustion engine operated over large areas of the characteristics map with stratified charge by way of fuel injection during the compression stroke. In order to guarantee reliable mixture ignition and combustion, the method of the present invention provides an ignition system which generates alternating voltage so that high voltage rapidly builds up between the electrodes of a spark plug, and generates ignition sparks with a spark duration that can be defined as a function of operating point.

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: A direct injection combustion engine includes a combustion chamber that includes a fuel intake port, an air intake port and a spark plug insertion opening. A spark plug includes a firing electrode, a ground electrode, and an insulator core nose. The spark plug is installed in the spark plug insertion opening so that the firing electrode, the ground electrode, and the insulator core nose extend into the chamber. A shield is positioned between the fuel intake port and the spark plug insertion opening and reduces the flow of fuel from the fuel intake port to the insulator core nose without preventing the flow of fuel to a spark gap formed between the firing electrode and the ground electrode.

Abstract: An internal combustion engine having fuel injection with a protrusion placed between a fuel injection nozzle and a spark plug in the combustion chamber. The protrusion shields the core nose of the spark plug, but not the gap between the center electrode and ground electrode of the spark plug. In this fashion, combustion is enhanced and carbon buildup on the porcelain body of the spark plug is prevented, thereby lessening the likelihood of a malfunction by the spark plug.

Abstract: In an arrangement for a spark-igniting direct-injection internal combustion engine, a division of X by B (X/B) (B denotes a cylinder bore diameter of each cylinder and X denotes a distance from a fuel injection nozzle up to a center axial line of the corresponding cylinder) ranges from 0.38 to 0.46. A division of Y by B (Y/B) ranges from 0.4 to 0.5 (wherein Y denotes a distance from a line passing through a spark-ignition portion of a spark plug up to an injection nozzle of the fuel injection valve. A division of Z by B (Z/B) ranges from 0.2 to 0.3 (wherein Z denotes a distance from the nozzle of the fuel injection valve up to a center of the intake valve).

Abstract: A direct-injection diesel engine in which a shallow-dish type piston cavity is formed on a top surface of a piston; wherein in the vicinity of the top dead center, a squish area is defined mainly by the top surface of the piston and an inner surface of a cylinder head opposite the top surface; when a velocity of a reverse squish flow from the shallow-dish type piston cavity to the squish area, generated due to a movement of the piston and is represented by Vs, and a fuel spray velocity in the vicinity of a lip portion of the shallow-dish type piston cavity is represented by Vsp, the distance between opposite wall portions of the shallow-dish type piston cavity is set such that the ratio Vs/Vsp is not greater than 1.25; and the squish area constitutes a part of the combustion chamber.

Abstract: A direct fuel injection ignition engine includes combustion chambers with a pent roof type ceiling. Each piston has a top surface with a configuration complementary to the combustion chamber ceiling. A fuel injector is disposed at a peripheral portion of the combustion chamber and injects fuel toward the center portion of the top surface of the piston. A cavity is formed on the top surface of the piston. The cavity has a configuration of an elongated circle with a substantially flat bottom surface. The surrounding side wall of the cavity is substantially upright in relation to the bottom surface. A cavity centerline drawn through the longitudinal axis of the cavity is perpendicular to the injection axis line and offset from the center of the piston toward the injector.

Abstract: An internal combustion engine is disclosed in which, at least during part load and full load operation of the engine, fuel is injected into the combustion chamber (10) during the intake stroke while an intake valve (26) is open by means of an injector (50) positioned in an unswept part of the cylinder bore (14). The fuel spary passes through the mouth of the intake valve (26) against the flow of high velocity air leaving the intake valve (26) and enters directly into the end of the intake port (20) penetrating laterally across the through-flow cross section of the intake port (20).

Abstract: In an internal combustion engine with direct fuel injection having a cylinder, a piston and a cylinderhead defining together a combustion chamber, a fuel injector with a fuel injection nozzle is mounted in the cylinder head for delivering fuel from the fuel injection nozzle into the combustion chamber so as to form a mixture cone. A spark plug is mounted in a spark plug sleeve disposed in the cylinder head and projects into the combustion chamber beyond the spark plug electrodes and into the mixture cone so as to form at its front end adjacent the spark plug electrodes an open ignition chamber in which part of the rich fuel mixture of the fuel mixture cone is collected for ignition by the spark plug.

Abstract: A piston for a cylinder direct injection spark ignition internal combustion engine mounted on an automotive vehicle. The piston comprises a piston head including a protruded section which is protruded from a standard horizontal plane which is perpendicular to a center axis of the piston. The protruded section has a cavity whose periphery forms a generally circular ridgeline, and an inclined surface formed outside the ridgeline and extending toward a periphery of the piston head. The inclined surface continuously slopes down in a direction from the ridgeline to the periphery of the piston. The inclined surface forms an angle (.theta.1) ranging from 10 to 60.degree. relative to the standard horizontal plane. The cavity has a depth (A) within a range of from 3 to 9 mm which depth is an axial distance between a bottom surface of the cavity and the standard horizontal plane of the piston.

Abstract: The invention relates to a method for converting heat into work, a gaseous fuel being compressed and subsequently burnt and a drive means 2 being moved due to volumetric expansion generated as a result of combustion. In order to allow low-pollutant combustion, there is provision, according to the invention, for the compressed gaseous fuel to be burnt in a porous body 8.

Abstract: A direct injected, internal combustion engine combustion chamber configuration and injection control strategy. Stratification is accomplished by providing a piston bowl and air flow pattern within the combustion chamber through intake passage shape and squish action. The shape of the combustion chamber also provides rapid flame propagation even at low speeds and loads.

Abstract: Direct-injected, four-cycle internal combustion engines can be operated advantageously with charge stratification, with the fuel being injected into the combustion chamber during the compression stroke of the piston in the cylinder as a conical fuel stream. To ignite the stratified mixture cloud, an igniting spark jumps between the electrodes of a spark plug and thus contacts an ignitable mixture. In order to guarantee sufficient preparation and stable ignition and combustion of the fuel/air mixture in the long term, it is proposed that the electrodes be located outside a conical jacket of the fuel stream and that the combustion chamber roof be so designed that the conical jacket is formed during injection between the injector and the spark plug close to the wall of the combustion chamber roof. The mixture guided in the conical jacket is deflected outward in the direction of the electrodes as a result.

Abstract: An injection device for an internal combustion engine, especially a diesel engine, with a combustion chamber (16) for each defined by piston (2), cylinder and cylinder head (1), a multi-hole injection nozzle (5) and a shroud (3) projecting from the cylinder head (1) into the combustion chamber (16) and surrounding the nozzle (5) in such a way that a precombustion chamber is formed between shroud (3) and piston (2) at TDC, and a combustion process for an internal combustion engine, especially for a diesel engine, with an injection device as described hereinabove, wherein combined direct and swirl-chamber injection takes place in the vicinity of TDC.

Abstract: A gasoline direct-injection engine includes a cavity provided in a top portion of a piston and constituting a portion of a combustion chamber defined between a cylinder head and the top portion of the piston, a fuel injection valve mounted in the cylinder head for injecting gasoline directly into the combustion chamber, and a spark plug also mounted in the cylinder head to face the combustion chamber. In this gasoline direct-injection engine, the fuel injection valve facing a substantially central portion of a ceiling surface of the combustion chamber is mounted in the cylinder head to have an axis substantially parallel to an axis of the piston, and the cavity provided in the top portion of the piston and disposed below the fuel injection valve and the spark plug is defined so that it is deeper in an area corresponding to the spark plug than in an area corresponding to the fuel injection valve.

Abstract: A direct-injection spark-ignition four-stroke internal-combustion engine includes a combustion chamber (1) delimited by a piston (10), a cylinder and a cylinder head, an intake pipe (2) associated with an intake valve (6), an exhaust pipe (3) with which an exhaust valve (7) cooperates, an ignition element (8) and a fuel injection element (9). According to the invention, the fuel injection element (9) is situated close to the ignition element (8), in the same half of the cylinder head as the exhaust valve (7), the half cylinder itself being placed toward the front of the vehicle. Fuel injection element (9) can be placed below the ignition element (8).

Abstract: A direct-injection spark-ignition four-stroke internal-combustion engine includes a combustion chamber defined by a piston, a cylinder with a cylinder head, an intake pipe associated with an intake valve, an exhaust pipe with which an exhaust valve cooperates, and a first ignition device situated close to intake valve. The engine further includes a fuel injection element situated close to the first ignition device, with the intake pipe, the fuel injection element, and the first ignition device being situated in the same half of the cylinder head. The fuel injection element may be placed below the first ignition device. A second ignition device may be positioned in the half of the cylinder head containing the exhaust valve.

Abstract: A direct fuel injection type internal combustion engine includes a combustion chamber formed by a cylinder head having a spark plug, a fuel injector and an air intake means with a swirl control valve, a cylinder wall, and a piston head having a vaporization portion. The upper surface of the piston head has a vaporization portion defined with a bottom surface formed with a predetermined depth and slant, an arc-shaped first wall connected to the bottom surface and formed to exhaust side, an arc-shaped second wall connected to the bottom surface and formed parallel to the first wall, a protrusion portion formed between the first wall and the second wall, and an arc-shaped third wall connected to the bottom surface and formed to an intake side.

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.

Abstract: A direct cylinder injected internal combustion engine that is effective to provide a stratified stoichiometric mixture at the spark gap at the time of firing and also a homogenous mixture under high speed high load conditions. This is achieved without specially formed bowls in the head of the piston by creating tumble under low speed and lower load conditions and by spraying on the heads of the intake valves during high speed high load conditions to obtain a homogeneous mixture.

Abstract: The present invention aims to improve evenness of atomizing of fuel in a fuel injection valve. An inner bottom surface of a fuel injection chamber 16 opened or closed by a needle valve 12 is designed in semi-spherical shape, and an injection nozzle 17 is formed obliquely on its bottom surface. To reduce deviation of flow velocity distribution in axial direction of said injection nozzle 17 of the fuel entering said injection nozzle 17, position of the injection nozzle 17 is deviated to a direction rotated by 90.degree. from tilting direction of the injection nozzle 17 toward swirling direction of the fuel with respect to the center of the bottom surface of the fuel injection chamber 16. This is because, in case the injection nozzle 17 is provided at the center of the bottom surface of the fuel injection chamber 16, axial flow velocity reaches minimum at 90.degree. and reaches maximum at 270.degree..

Abstract: A spark-ignition type engine comprising a spark plug arranged at the center of the inner wall of the cylinder head and a fuel injector arranged at the periphery of the inner wall of the cylinder head. A cavity extending from a position beneath the fuel injector to a position beneath the spark plug is formed on the top face of the piston. The circumferential wall of the cavity extends archwise below the spark plug and has an arc shaped cross section.

Abstract: A direct injected, internal combustion engine combustion chamber configuration that employs a three intake valves per cylinder and direct cylinder injection. Stratification is accomplished by providing a piston bowl and air flow pattern within the combustion chamber through intake passage shape and squish action. The shape of the combustion chamber also provides rapid flame propagation even at low speeds and loads.

Abstract: A direct injection engine provided with an injector at a peripheral portion of a combustion chamber to inject at least at a latter stage of a compression stroke in at least in a low engine load and low engine speed condition, wherein a distance from the tip end of the injector to an opposite end the combustion chamber is determined greater than a traveling distance of an injected fuel for a time period from a start of a fuel injection at the latter stage of the compression stroke to the ignition timing, wherein; an ignition plug is arranged that an ignition gap is disposed within an injection area of the injector; and, wherein a distance from the tip end of the injector to the ignition gap is determined smaller than said traveling distance of the injected fuel. An ignitability and combustion stability can be improved to thereby improve a fuel consumption efficiency.

Abstract: An internal combustion engine has a piston reciprocable in a cylinder toward and away from a combustion chamber. An intake valve admits air into the combustion chamber. An exhaust valve discharges products of combustion from the combustion chamber. A fuel injector is positioned to direct a plume of fuel into the combustion chamber along a path and in a direction to impinge upon the exhaust valve. The piston has an end face formed with a concave recess or pocket adjacent the exhaust valve. The exhaust valve is constructed and arranged to deflect fuel impinging thereon into the recess. The recess being shaped to redirect fuel back toward the path of the plume of fuel.

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. Due to 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: In a method of providing an ignitable fuel/air mixture in the combustion chambers of the various cylinders of an internal combustion engine with direct fuel injection wherein fuel is injected into the combustion chambers by way of injectors including injection nozzles with valve members for controllably opening and closing the injection nozzles, the valve member opening strokes and the valve member opening times are variably adjusted depending on specific engine operating conditions.

Abstract: A combustion chamber of an in-cylinder direct fuel injection spark ignition engine having a pentroof composed of an intake side roof and an exhaust side roof, a piston, and a cylinder. The combustion chamber has a fuel injector provided between the intake side roof and the exhaust side roof inclined toward the exhaust side port, an intake port provided on the intake port side roof at an acute angle with respect to an extended line from the exhaust side roof so as to form a tumble flow of intake air along the exhaust side roof, a piston cavity with a curved surface formed on the top surface of the piston so as to reflect a fuel spray injected from the fuel injector together with that tumble flow in the direction of the intake side roof, and an electrode of a spark plug projected from the intake side roof so as just to collide with the tumble flow.

Abstract: A direct-injection and spark-ignition 4-stroke internal-combustion engine having at least one combustion chamber (1) including a piston (2), a cylinder (3), a cylinder head (4), several intake lines (5) associated with intake elements (6), an exhaust line (9) cooperating with an exhaust valve (11), and an ignition device (7) positioned close to intake elements (6). The upper face of the piston (2) has a profile close to that of the lower face of the cylinder head (4), and the piston (2) has a recess (12) in the vicinity of the area into which ignition device (7) opens. A fuel injection element (8) is positioned in the vicinity of the ignition device (7), and one of the intake elements (6) has a longitudinal axis close to the longitudinal axis of the cylinder (XX').

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 cylinder wall fuel injector is provided with a deflector that causes a fuel spray to be deflected from its normal path directly across a cylinder and perpendicular to a centerline of the cylinder. The deflector is positioned between an opening in the tip of the fuel injector and the cylinder into which the fuel is sprayed. The deflector causes the fuel to be redirected away from a direct line toward the exhaust port of the cylinder.

Abstract: The invention relates to a four-stroke internal combustion engine with spark ignition and direct injection of the fuel into the combustion chamber, with a reciprocating piston for each cylinder and a roof-shaped top of the combustion chamber with at least one exhaust valve and at least two intake valves, as well as intake ports generating a tumble flow in the combustion chamber, as well as a fuel injection device opening into the combustion chamber, and an ignition source located in the area of the cylinder axis in the roof of the combustion chamber.

Abstract: A gaseous fuel direct injection fuel system for a spark ignited internal combustion engine having an inlet port for admitting combustion air into a combustion chamber of the engine, the direction injection system including at least one fuel injector for directly injecting gaseous fuel into the combustion chamber, and means for supplying gaseous fuel to the fuel injector, a quantity of gaseous fuel being injected into the combustion chamber by the fuel injector, wherein at least at some operating condition thereof, the injection of the gaseous fuel is initiated after the closing of the inlet port, and wherein the injection of the gaseous fuel is completed before the compression stroke of the engine is substantially completed.

Abstract: Otto internal-combustion engines having one injector respectively per cylinder for the internal mixture formation can be operated at full load or high partial load by fuel injection in the suction stroke of the piston and, at medium or low partial load, with a compression stroke injection. The compression stroke injection, which is advantageous in this load range, because of low average combustion space temperatures and the tendency to form deposits in the combustion space because of residues of liquid fuel and the resulting impaired operating conditions, can partially be carried out only to a limited degree.

Abstract: An internal combustion engine having a cylinder head body with a pentroof-shaped combustion chamber comprises a piston including a piston cavity and a caldera-shaped protrusion provided around the piston cavity, a fuel injector for injecting fuel downward to the piston cavity and a spark plug disposed obliquely in proximity to an intake valve. The piston cavity is provided on the top surface of the piston being offset on the spark plug side. Further, the caldera-shaped protrusion is slanted towards the spark plug side. Therefore, injected fuel collides against a down-slope of the piston cavity and is diffused partly towards the spark plug and partly towards the cylinder head. As a result, a locally rich air-fuel mixture is formed around the spark plug so as to enable stratified charge combustion.

Abstract: In order to optimize combustion in a four-stroke spark-ignition engine with direct fuel injection, the conditions of charge flow are improved by providing the top surface of each piston with an essentially T-shaped configuration of guiding ribs, i.e., a longitudinal rib extending transversely to the crankshaft axis running and a cross-rib running in the direction of the crankshaft axis.

Abstract: A cylinder direct injection spark-ignition engine in which fuel is directly injected into each cylinder. The engine comprises intake and exhaust valves movably disposed to a cylinder head. A piston is movably disposed in a cylinder in a cylinder block so as to define a combustion chamber. The piston is formed at its piston crown with a generally circular cavity having a center axis which is offset from a center axis of the piston toward the intake valve. A spark plug is provided such that its tip end section is disposed above a part of a peripheral portion of the circular cavity which part is located closer to the center axis of the piston than to periphery of the piston. A device for generating swirl of intake air in the combustion chamber is provided.