Abstract: A method of controlling the fuel injection in an internal combustion engine (1) having a piston (3), which passes to and for in a cylinder (2) between an upper and a lower dead center, and an injection nozzle (4), which is disposed in the cylinder (2), the method including the steps whereby a primary injection of fuel is realized in the cylinder (2), which fuel is ignited and causes the piston (3) to be moved in the direction of the lower dead center in the cylinder (2), and whereby a post-injection of a fluid is realized in the cylinder (2). The injection pressure of the fluid in the post-injection is higher than the injection pressure of the fuel in the primary injection.

Abstract: A dual mode fuel injector having first (15) and second (30) valve members. The valve members are actuatable independently of one another and are arranged to open in opposite directions. The valve members control the flow through first (18) and second (29) orifices, one of which injects the fuel at a narrow angle with respect to the injector axis, and the other of which injects the fuel at a wider angle with respect to this axis.

Abstract: A combustion chamber assembly for use in a piston of a diesel engine includes a combustion chamber being defined in a crown of a piston, the combustion chamber having a center portion, the center portion being defined at least in part by a surface being a portion of a convex sphere to define a post, the sphere having a radius and an origin, the origin of the radius lying on a combustion chamber central axis and the combustion chamber further having an outwardly radially disposed sidewall margin, the sidewall margin being defined in part by an annular surface, the annular surface being concave and having an origin and a radius. The combustion chamber is further defined by an annular bowl lip surface. A piston and a method of forming a combustion chamber are further included.

Abstract: A Divided Chamber combustion system comprising an energy-cell built in the bottom of a deep piston bowl; aligned in the cylinder's centerline; in fluid communication with the main combustion chamber through one main transfer passage disposed in its centerline and a plurality of auxiliary transfer passages circularly disposed around it. Each auxiliary transfer passage is at least inclined on a plane parallel to the cell's centerline. The injection nozzle, centrally-located in the fire deck of the cylinder head, includes a central pintle discharging fuel on the cylinder's centerline; and a plurality of small auxiliary orifices circularly surrounding the central pintle; discharging at a radial angle to the cylinder's centerline.

Abstract: A direct cylinder injection-type spark ignition internal combustion engine is disclosed. The engine comprises a spark plug, a cavity formed in the top surface of a piston, and a fuel injection valve for injecting fuel into the cavity in nearly the shape of a fan having a relatively small thickness. When the fuel injected in nearly the shape of a fan from the fuel injection valve is considered by being divided into a plurality of fuel segments in a radial direction, a side wall of the cavity has a first fuel deflection passage 82a and a second fuel deflection passage 82b for so deflecting at least two of the plurality of fuel segments as to pass near the spark plug. The side wall of the cavity is at least partly provided with a return portion 83 that protrudes toward the inside of the cavity.

Abstract: The present invention relates to a direct-injection internal-combustion engine comprising at least a cylinder (10), a cylinder head (12), a piston (22) sliding, in this cylinder, intake means (14, 18) for at least one gaseous fluid, a multijet fuel-injection nozzle (24) comprising a fuel jet angle (&bgr;) and a fuel jet nappe angle (a1), and a combustion chamber delimited on one side by the upper face of piston (22), said face comprising a teat (36) pointing towards the cylinder head and arranged in a concave bowl (34).

Abstract: A direct fuel injection engine has a fuel injection valve that injects fuel toward a cavity formed in a top of a piston, and a spark plug that ignites the fuel-air mixture resulting from the fuel injection. The direct fuel injection engine is configured to strengthen the penetration of the fuel streams, to improve the directionality of the fuel streams and to stably form an agglomerate fuel-air mixture close to the spark plug. The cavity preferably has a bottom surface, a curved surface, and a flat surface. In a plan view taken along the center axis of the engine cylinder, cavity C is shaped like an ellipse whose foci are located at the tip of fuel injection valve and the spark discharge gap of spark plug, respectively. The fuel injection valve has a plurality of injection vents that spray solid-core fuel streams.

Abstract: The in-cylinder fuel injection engine is characterized in that fuel is injected into the combustion chamber in two directions. When the homogeneous charge combustion is performed, a first spray block of fuel is injected inside of the cavity and a second spray block of fuel is injected outside of the cavity. When the stratified charge combustion is performed, both spray blocks are injected inside of the cavity.

Abstract: An internal combustion engine with a new combustion chamber comprising: short-flap pistons having an absolutely flat head; a cylinder cover having an absolutely flat bottom surface, and a distance “X” between the piston head and the bottom surface of the cylinder cover when the piston is at its TDC, which forms the combustion chamber, i.e., the space comprised between the piston's top surface or piston head, the walls of the cylinder, and the bottom flat surface of the cylinder cover.

Abstract: To suppress deposition of fuel injected at an early timing on a wall surface for preventing the degradation in fuel efficiency and increase in the amount of harmful components in an exhaust gas, in a direct-injection diesel engine which controls the injector to cause a combustion configuration dominated by the compressive ignition of the premixture while the engine is in the premixed combustion region defined on a low load side. When fuel is injected at an early timing to form the premixture, at least one of the pulse width to be inputted into the injector and the fuel pressure is or are adjusted according to the change in the injection timing, and corrected according to the intake air temperature or the intake pressure. If an allowable pulse width is insufficient to inject fuel in the amount corresponding to a target torque, fuel is injected in a divided manner.

Abstract: In a method for the injection of Diesel fuel into a combustion chamber of a Diesel engine by way of a fuel injection valve with a plurality of pilot and main fuel injection ports, the fuel is injected during partial load operation only by way of the pilot injection ports such that a homogeneous mixture is formed and, under full load operation, fuel is additionally injected—after a pause—through the main fuel injection ports in such a way that a fuel jet bundle is formed in combination with the fuel jets formed by the pilot ports which is extends over the whole periphery of the combustion chamber. The fuel injection valve has the main fuel ports arranged in a piezo-actuated tappet in series in the direction of the opening movement of the tappet behind the associated pilot ports. With the piezo drive the opening stroke of the tappet can be controlled so as to provide fuel injection pauses between the pilot fuel injection and the main fuel injection.

Abstract: The invention relates to a method for operating an internal combustion engine operated with a self-ignitable fuel, with an approximately homogeneous fuel-air mixture being produced in the combustion chamber in the self-ignition ranges (CI), a high compression ratio suitable for a self-ignition of the fuel being provided and the combustion occurring in the self-ignition ranges (CI) predominantly by self-ignition. In order to control the start of combustion in the self-ignition range (CI) in the easiest possible way it is provided that in the self-ignition range (CI) the pressure and/or temperature of the homogeneous fuel-air mixture are set in such a way, preferably depending on the charge composition and/or charge temperature, that the self-ignition would be achieved only after the actually desired start of combustion in the zone of the upper dead center and the combustion of the homogeneous fuel-air mixture is initiated locally in the self-ignition range (CI) by an external energy impulse.

Abstract: The invention relates to a spark-ignition engine having direct fuel injection, the fuel injector (2) and the spark plug (3) being arranged centrally on the upper side of the combustion chamber (1). The fuel injector produces an asymmetrical injection volume, so that the electrodes of the spark plug (3) are not directly affected by liquid fuel. The electrodes are, however, situated in a region reached by evaporating fuel.

Abstract: A combustion chamber assembly for use in a diesel engine includes a combustion chamber being defined in a crown of a piston, the combustion chamber having a center portion, the center portion being defined at least in part by a portion of a convex sphere to define a post, the sphere having a radius and an origin, the origin of the radius lying on a combustion chamber central axis and the combustion chamber further having an outwardly radially disposed bottom margin, the bottom margin being defined in part by a portion of a sphere, the sphere being concave and having an origin and a radius. The combustion chamber has more than two spherical surfaces having smooth annular transitions between adjacent spherical surfaces, the spherical surfaces including the spherical center portion and the spherical bottom margin. A piston and a method of forming a combustion chamber are further included.

Abstract: A direct fuel injection engine has a fuel injection valve that injects fuel toward a cavity formed in a top of a piston, and a spark plug that ignites the fuel-air mixture resulting from the fuel injection. The direct fuel injection engine is configured to strengthen the penetration of the fuel streams, to improve the directionality of the fuel streams and to form in the cavity an agglomerate fuel-air mixture that is homogeneous and has uniform concentration. The cavity preferably has a bottom surface, a curved surface, and a flat surface. The fuel injection valve has a plurality of injection vents that spray solid-core fuel streams with angles formed between adjacent injection vents that are less than or equal to the spray angle of the fuel stream sprayed from each injection vent. The fuel streams form a combined fuel stream having a hollow circular cone shape.

Abstract: A direct fuel injection engine has a fuel injection valve that injects fuel toward a cavity formed in a top of a piston, and a spark plug that ignites the fuel-air mixture resulting from the fuel injection. The direct fuel injection engine is configured to strengthen the penetration of the fuel streams, to improve the directionality of the fuel streams and to stably form an agglomerate fuel-air mixture close to the spark plug. The cavity preferably has a bottom surface, a curved surface, and a flat surface. In a plan view taken along the center axis of the engine cylinder, cavity C is shaped like an ellipse whose foci are located at the tip of fuel injection valve and the spark discharge gap of spark plug, respectively. The fuel injection valve has a plurality of injection vents that spray solid-core fuel streams.

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: A multizone combustion chamber and method of combustion in a compression-ignited reciprocating engine. The combustion chamber includes a cylinder, a cylinder head located at one end of the cylinder, a piston that reciprocates in the cylinder, an inlet that supplies a gas into the combustion chamber during an induction stroke of the piston, and an injector that supplies a fuel into the combustion chamber. The combustion chamber defines a primary chamber and at least a secondary chamber when the piston is located in a predetermined position near the cylinder head. Combustion is initiated in the primary chamber while preventing combustion from occurring in the secondary chamber. Combustion in the secondary chamber is delayed until after the piston and the cylinder head have been separated and thermodynamic communication between the fuel/gas mass in the primary chamber and the fuel/gas mass in the secondary chamber is possible.

Abstract: A combustion system for direct injection diesel engines, having a fuel injection nozzle provided with upper and lower rows of nozzle holes and disposed so as to be opposed to a deep dish combustion chamber of a small opening ratio. The directions of the upper nozzle holes (1) in the upper row and those of the lower nozzle holes (2) in the lower row are set so that fuel injected from the upper nozzle holes (1) reaches a side wall of the combustion chamber and fuel injected from the lower nozzle holes (2) impinges upon a bottom surface (4) of the combustion chamber. A ratio of a fuel spray travel from the upper nozzle holes (1) to a diameter of each of the upper nozzle holes is set to 150-250. The number of said upper nozzle holes (1) is set twice as large as that of said lower nozzle holes (2).

Abstract: A combustion chamber assembly for use in a diesel engine includes a combustion chamber being defined in a crown of a piston, the combustion chamber having a center portion being elevated relative to a bottom plane of the combustion chamber, the center portion being defined in part by a portion of a convex sphere, the sphere having a radius and an origin, the origin of the radius lying on a piston central axis and the combustion chamber further having an outwardly radially disposed bottom margin, the bottom margin being defined in part by a portion of a concave sphere, the sphere having a radius, the origin of the radius lying on the piston central axis and being greater than the center portion radius. The combustion chamber has a plurality of curved surfaces having smooth transitions between adjacent smooth surfaces, the smooth surfaces including the spherical center portion and the spherical bottom margin in combination with an annular sidewall surface.

Abstract: In an ignition electrode arrangement for a cyclinder in an internal combustion engine, for example at Otto engine, a cyclinder head (3) bears a first electrode (7) and a second electrode (8) which interact with one another. At least the first electrode (7) is arranged on an ignition means (6) fastened in the cyclinder head. According to the invention, the second electrode (8) is movable relative to the cyclinder head (3) and the first electrode (7) in order to make it possible to change the spark gap. The second electrode (8) can be mounted on the cyclinder head (3) itself or on the ignition device (6). The size of the spark gap is controlled during operation by the ignition system of the engine.

Abstract: Cleaning of exhaust gas and reduction of fuel costs are aimed at while realizing homogenious charge (or pre-mixing) compression ignition combustion and performing fuel injection in a suitable manner in all regions of engine operation. In a direct injection diesel engine there are provided an conventional injection mode in which fuel is injected with a timing (I) in the vicinity of the compression top dead center of piston (1) and a homogenious charge compression injection mode in which fuel is injected with a timing (II to V) which is earlier than that in the conventional injection mode, and such that fuel ignition does not occur at least until injection has been completed, fuel injection being performed by the conventional injection mode during full load operation of the engine and fuel injection being performed by the homogenious charge compression injection mode during part (low/medium) load operation of the engine.

Abstract: A multizone combustion chamber and method of combustion in a compression-ignited reciprocating engine. The combustion chamber includes a cylinder, a cylinder head located at one end of the cylinder, a piston that reciprocates in the cylinder, an inlet that supplies a gas into the combustion chamber during an induction stroke of the piston, and an injector that supplies a fuel into the combustion chamber. The combustion chamber defines a primary chamber and at least a secondary chamber when the piston is located in a predetermined position near the cylinder head. Combustion is initiated in the primary chamber while preventing combustion from occurring in the secondary chamber. Combustion in the secondary chamber is delayed until after the piston and the cylinder head have been separated and thermodynamic communication between the fuel/gas mass in the primary chamber and the fuel/gas mass in the secondary chamber is possible.

Abstract: A method for operating a reciprocating-piston internal combustion engine, having an injector nozzle operable by a single valve element and configured to directly inject a fuel into a combustion chamber and having a piston including a piston crown and a piston recess, includes the steps of injecting the fuel by the injector nozzle into the combustion chamber in the form of separated jets of the fuel having different inclinations relative to a top surface of the piston crown and selectively setting the inclinations of the fuel jets depending on an engine load.

Abstract: A combustion chamber assembly for use in a diesel engine includes a combustion chamber being defined in a crown of a piston, the combustion chamber having a center portion being elevated relative to a bottom plane of the combustion chamber, the center portion being defined in part by a portion of a convex sphere, the sphere having a radius and an origin, the origin of the radius lying on a piston central axis and the combustion chamber further having an outwardly radially disposed bottom margin, the bottom margin being defined in part by a portion of a concave sphere, the sphere having a radius, the origin of the radius lying on the piston central axis and being greater than the center portion radius. The combustion chamber has a plurality of curved surfaces having smooth transitions between adjacent smooth surfaces, the smooth surfaces including the spherical center portion and the spherical bottom margin in combination with an annular sidewall surface.

Abstract: An engine combustion chamber includes a cylinder head, a cylinder wall and a piston. The piston has a bowl volume formed therein. A fuel injector is disposed adjacent one edge of the bowl and an ignition source is within a predetermined distance of another, substantially opposite, edge of the bowl. The bowl has a transporting surface which directs a fuel-air charge from the bowl volume toward the ignition source. The piston, bowl and cylinder head cooperate through a plurality of design features to provide an efficient combustion chamber.

Abstract: An engine in which the cylinders are scavenged according to a cross scavenging technique. The engine includes one or more cylinders in each of which a piston is disposed for reciprocal motion. The engine further includes a direct fuel injection system that allows controlled input of fuel into each cylinder to promote more efficient operation of the cross scavenged engine.

Abstract: A fuel injection system (1) for an internal combustion engine (1′) includes a fuel injector (4) which injects fuel into a combustion chamber (7) delimited by a cylinder wall (14) in which a piston (6) is guided, and having a spark plug (3) projecting into the combustion chamber (7), the fuel injector (4) producing multiple injection jets (10) in the combustion chamber (7). At least one gap (15) is provided in the injection jets (10) in an area remote from the spark plug (3).

Abstract: Internal combustion engine with fuel injection directly into the combustion chamber of the engine. The engine has inlet channels, the angle of incidence (valve angle) (&agr;) of which is greater than 20° relative to the longitudinal axis of the cylinder chamber. The piston tops are made, firstly, with a surface portion inclined relative to a plane normal to the longitudinal axis of the cylinder chamber by an angle (&ggr;) equal to or less than the angle of incidence of the inlet channel, and, secondly, with a cavity connected to the inclined surface portion. By interaction between the angle of incidence of the inlet channels and the shape of the piston tops, there is generated in the combustion chambers a primary vortical movement in the inlet air about an axis perpendicular to the longitudinal axis of the cylinder chamber. The primary vortical movement generates a secondary vortical movement in the opposite direction in the piston cavity.

Abstract: In a method for the injection of Diesel fuel into a combustion chamber of a Diesel engine by way of a fuel injection valve with a plurality of pilot and main fuel injection ports, the fuel is injected during partial load operation only by way of the pilot injection ports such that a homogeneous mixture is formed and, under full load operation, fuel is additionally injected—after a pause—through the main fuel injection ports in such a way that a fuel jet bundle is formed in combination with the fuel jets formed by the pilot ports which is extends over the whole periphery of the combustion chamber. The fuel injection valve has the main fuel ports arranged in a piezo-actuated tappet in series in the direction of the opening movement of the tappet behind the associated pilot ports. With the piezo drive the opening stroke of the tappet can be controlled so as to provide fuel injection pauses between the pilot fuel injection and the main fuel injection.

Abstract: An internal combustion engine includes an engine housing that defines a main combustion chamber separated from a precombustion chamber by a flame communication passage way. A source of gaseous fuel is fluidly connected to one end of a fuel supply passage. A check valve, which includes a valve body with a valve seat, and a valve member, is positioned between the other end of the fuel supply passage and the precombustion chamber. The valve member is moveable between an open position and a closed position. The valve body and the valve member define a fluid passage that fluidly connects the fuel supply passage to the precombustion chamber when the valve member is in its open position. The valve body and the valve member substantially fluidly isolate the valve seat from the precombustion chamber when the valve member is in its closed position.

Abstract: The invention relates to a method for operating an internal combustion engine operated with a self-ignitable fuel, with an approximately homogeneous fuel-air mixture being produced in the combustion chamber in the self-ignition ranges (CI), a high compression ratio suitable for a self-ignition of the fuel being provided and the combustion occurring in the self-ignition ranges (CI) predominantly by self-ignition. In order to control the start of combustion in the self-ignition range (CI) in the easiest possible way it is provided that in the self-ignition range (CI) the pressure and/or temperature of the homogeneous fuel-air mixture are set in such a way, preferably depending on the charge composition and/or charge temperature, that the self-ignition would be achieved only after the actually desired start of combustion in the zone of the upper dead center and the combustion of the homogeneous fuel-air mixture is initiated locally in the self-ignition range (CI) by an external energy impulse.

Abstract: An internal combustion engine comprises an engine housing which defines a main combustion chamber that is separated from a precombustion chamber by a flame communication passageway. The engine housing further defines a fuel supply passage with one end and an opposite end. A source of fuel is fluidly connected to the opposite end of the fuel supply passage. A check valve which includes a valve body with a valve seat and a valve member is positioned between the one end of the fuel supply passage and the precombustion chamber. The valve member is movable between an open position and a closed position. The valve body and the valve member define a relatively wide fluid passage that fluidly connects the fuel supply passage to the precombustion chamber when the valve member is in the open position. The valve body and the valve member define a relatively narrow stagnation region separating the valve seat from the precombustion chamber when the valve member is in the closed position.

Abstract: In an in-cylinder fuel injection two cycle engine, a combustion chamber dome and a piston cavity are provided in an offset position from a cylinder bore center axis to an exhaust port side, respectively. A spark plug is mounted in a cylinder head such that its electrode is positioned in vicinity of the cylinder bore center axis in the dome. Further, a fuel injector is mounted in the cylinder head such that its injection nozzle is positioned around an outer periphery edge of the dome on the exhaust port side and fuel is injected from the injection nozzle toward the piston cavity. The piston cavity is shaped into a concavely spherical surface so as to direct injected fuel toward the electrode of the spark plug, thereby locally rich, combustible mixture being formed around the spark plug.

Abstract: An internal combustion engine comprises an engine housing which defines a main combustion chamber that is separated from a precombustion chamber by a flame communication passageway. The engine housing further defines a fuel supply passage with one end and an opposite end. A source of fuel is fluidly connected to the opposite end of the fuel supply passage. A check valve which includes a valve body with a valve seat and a valve member is positioned between the one end of the fuel supply passage and the precombustion chamber. The valve member is movable between an open position and a closed position. The valve body and the valve member define a relatively wide fluid passage that fluidly connects the fuel supply passage to the precombustion chamber when the valve member is in the open position. The valve body and the valve member define a relatively narrow stagnation region separating the valve seat from the precombustion chamber when the valve member is in the closed position.

Abstract: A direct injection engine in which an injector injects fuel toward a cavity formed in a top surface of a piston to produce a locally distributed mixture around a spark plug is constructed such that the direction of a fuel spray ejected from the injector is varied during a fuel injection period to properly spread the mixture and prevent its local overrichness. The direct injection engine is provided with means for generating a swirl, for example, so that the fuel spray from the injector is directed toward the spark plug when the pressure in a cylinder is low in a compression stroke, and the fuel spray is deflected by the swirl away from the direction of the spark plug as the pressure in a cylinder increases.

Abstract: A stratified-charge combustion chamber system for a direct-injection spark-ignited (DISI) engine with a swirl-type airflow. An asymmetrical combustion bowl design in the top wall of the piston provides a wide area on the downstream side of the swirl flow and a harbor area upstream of the swirl flow in a direction further away from the fuel injector. The edge of the combustion bowl is comprised of smoothly-connected curves with large radii, except for the curve connecting the wide and harbor areas, which has a small radius. The vertical cross-sections of the bowl also have large radii in order to guide the air-fuel mixture and rebounded fuel droplets toward the spark plug and prevent dead regions for the fuel. The precise position of the spark plug in the harbor area can be adjusted as desired within a certain range to improve ignitability of the air-fuel mixture.

Abstract: A combustion chamber arrangement for a direct fuel injected internal combustion engine wherein the combustion chamber is formed in part by a recess in the piston head. Fuel is injected into the combustion chamber so as to be introduced on one side of the recess with a spark plug being positioned so that its gap lies diametrically opposite the fuel injector. An arrangement is provided for introducing a swirl to the flow of fuel and the combustion chamber recess is canted so that its lower surface is deeper where the fuel first enters then on the other side so as to improve flame propagation and complete combustion while maintaining a high compression ratio.

Abstract: An internal combustion gasoline engine has an air intake assembly which injects air through the cylinder head into the cylinder to generate swirl (horizontal vortex) flow (as opposed to tumble (vertical vortex) flow) for stratified charge combustion, and to generate tumble flow for homogeneous charge combustion. The piston includes a cavity combustion chamber at the top surface of the piston, the cavity combustion chamber having an increasing cross sectional area as the top of the piston is approached.

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 direct injection gasoline engine includes at least one cylinder, a piston reciprocably mounted within the cylinder, a cylinder head closing the cylinder and at least one inlet port adapted to cause swirl of the inlet air in the cylinder substantially about the axis of the cylinder. The crown of the piston is provided with a recess which has a floor and a side wall and constitutes at least part of the combustion chamber. A spark plug extends close to or into the recess, at the top dead centre position of the piston, at a position adjacent to the side wall of the recess. A fuel injector is arranged to inject fuel into the recess and is situated adjacent the side wall of the recess. That portion of the side wall of the recess which is between the fuel injector and the spark plug is arcuate, when viewed in the axial direction of the cylinder.

Abstract: A process for operating of an internal combustion engine running on fuel that is both externally ignitible and self-ignitible, especially gasoline, the operating region of the engine including self-ignition or compression-ignition (CI) regions and external-ignition or spark-ignition (SI) regions, and a high compression ratio suitable for self-ignition of the fuel being provided, at least in compression-ignition regions, and combustion being initiated by self-ignition of the fuel-air mixture in compression-ignition regions and by spark-ignition of the fuel-air mixture in spark-ignition regions, and part-load operation being assigned to the compression-ignition region, whilst full-load operation and/or operating modes with high engine load as well as cold starts are assigned to the spark-ignition region. In order to improve the quality of the exhaust gases while maintaining high efficiency, a largely homogeneous fuel-air mixture should be produced in the combustion chamber in the compression-ignition region.

Abstract: A two or four stroke valve engine including at least one cylinder (3) within which a piston (4) moves and which receives an air-fuel mixture via at least one induction or intake duct (16). For the combustion products, at least one exhaust duct (17) is operationally connected to the cylinder. The intake duct (16) and the exhaust duct (17) each are provided with at least one respective valve member (18, 19) subjected to an operator device (25, 26) to open it during the use of the engine, and a closure device (28) retuning the valve member (18, 19) into the position in which it closes the respective duct (16, 17). The valve members (18, 19) are positioned to the side of the cylinder (3) and intercept apertures (16A, 17A) of the respective ducts (16, 17), which open into at least one mixing chamber (13) positioned to the side of the cylinder (3) and communicating with it. At least in correspondence with the chamber (13), an ignition device (8) for the mixture present in it is provided.

Abstract: A direct injection internal combustion gasoline engine has a piston 4 which includes a first inclined surface 22 approximately parallel to an intake-side inclined surface 11a of a cylinder head and a second inclined surface 23 approximately parallel to an exhaust-side inclined surface 11b of the cylinder head. A cavity combustion chamber 12 is recessed in the first inclined surface. A pair of valve recesses 31, 32 is also recessed in the first inclined surface. An arcuate dam section 21a is formed along the periphery of the valve recesses with the first inclined surface.

Abstract: A diesel cycle, direct injected internal combustion engine is provided with a piston recess or bowl into which fuel is injected each combustion cycle. One or more reaction chambers adjacent the piston recess are in communication with the recess through an array of discrete orifices located along the side wall of the recess. Partial reaction of fuel and air in the reaction chambers each combustion cycle produces radicals including intermediate species for seeding a fuel air mixture of a following combustion cycle through a delayed discharge of radicals from the reaction chamber into the piston recess. The discrete orifices are arranged in a specific array that ensures a desired chaotic flow in the reaction chambers and maximum interaction between radicals discharged from the reaction chamber and the soot cloud formed in the combustion chamber upon ignition of the fuel air mixture in the piston recess.

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 piston for a direct fuel injection engine is described. The piston comprises a cylindrical skirt and a piston face. The cylindrical skirt has an axis. The piston face has a bowl. The bowl has a wall extending about an axis in inclined relation to the cylindrical skirt axis. An engine is also described. The engine comprises an engine block defining an engine cylinder and a piston moveable axially in the engine cylinder. The piston comprises a cylindrical skirt and a dome-shaped piston face, the piston face having therein a bowl. The bowl located with the cylinder axis passing therethrough. The bowl is defined by a cylindrical wall extending about an axis extending in inclined relation to the axis of the cylinder. The bowl includes a bottom wall extending perpendicularly to the bowl axis. The engine also comprises a fuel injector nozzle adapted to direct a spray of fuel toward the bowl for deflection toward a spark plug disposed on the opposite side of the cylinder axis from the fuel injector.

Abstract: A piston for an internal combustion engine has a re-entrant type combustion bowl. The combustion bowl has two re-entrant volumes in fluid communication and cascaded with respect to the longitudinal axis of the piston. The cascaded re-entrant volumes enhance gas velocities within the combustion bowl to improve fuel combustion.

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: 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.