Abstract: The present invention relates to a method of controlling a spark-ignition supercharged internal-combustion engine, notably of gasoline type, comprising at least one cylinder (12) with a combustion chamber (14), at least two intake means (24, 26), at least one fuel injection means (40, 42), at least one exhaust means (28, 30) and an ignition means (52). According to the invention, the method consists in preparing a fuel mixture with a fuel/air ratio greater than or equal to 1, another fuel mixture is prepared with a fuel/air ratio below 1, the two fuel mixtures are fed into the combustion chamber so as to obtain a part (C1) of this chamber containing a fuel mixture with the fuel/air ratio greater than or equal to 1 and the remaining part (C2) of the chamber containing the fuel mixture with the fuel/air ratio below 1.

Abstract: A method of operating an engine for a vehicle having at least a first cylinder, the method comprising of operating the first cylinder to provide at least one of compression braking and expansion braking by holding one of an intake valve and an exhaust valve of the first cylinder closed while opening, closing, and opening the other of the intake valve and the exhaust valve during a cycle of the first cylinder and during a first vacuum level of an intake manifold upstream of the first cylinder; and operating the first cylinder to provide at least one of compression braking and expansion braking by operating both the intake valve and the exhaust valve of the first cylinder during a cycle of the first cylinder to allow at least some air to flow through the first cylinder during a second vacuum level of the intake manifold.

Abstract: A cylinder of an internal combustion engine is communicated with intake ports. Each of intake valves and each of fuel injection valves are provided to a corresponding one of the intake ports to inject fuel into a combustion chamber through a curved portion and an opening of the corresponding intake port. An injection axis of each fuel injection valve intersects with a surface of the corresponding intake valve placed in a close position at an intersecting point that is located on an upstream side of a central axis of the corresponding intake valve.

Abstract: The present invention relates to a method of controlling an indirect-injection engine, notably a supercharged engine, in particular a spark-ignition engine, comprising at least one cylinder (10) including a combustion chamber (12), at least two air intake means (14, 16) comprising each a pipe (18, 20) controlled by an intake valve (22, 24), at least one fuel injection means (26, 28) associated with each intake means and at least one burnt gas exhaust means (30) with an exhaust valve (32), said engine running according to two intake modes, a mode with burnt gas scavenging and a mode without scavenging, characterized in that it consists in: supplying, in intake mode with scavenging, non-carbureted air through one (16) of the intake means then, in the vicinity of the scavenging end, in supplying carbureted air through the other (14) intake means, supplying, in intake mode without scavenging, carbureted air through the two intake means (14, 16).

Abstract: An internal combustion engine wherein the top wall surface of the intake air inflow passage part of the intake port is formed by a first top wall surface and a second top wall surface lower than the first top wall surface and wherein a lower layer flow passage and an upper layer flow passage are formed at the height position of the second top wall surface as a boundary. When the intake valve opens, a lower layer flow flowing through the inside of the lower layer flow passage passes through the intake valve opening region, flows to the circumferential direction of the combustion chamber, and generates a swirl, while an upper layer flow flowing through the inside of the upper layer flow passage passes through the helical part and flows into the combustion chamber.

Abstract: A method for controlling the air-fuel ratio of an internal combustion engine operating with alternating intake valves is presented. According to the method, engine air-fuel ratio can be adjusted by changing valve timings or fuel during a cylinder cycle.

Abstract: A method for controlling a supercharged engine, that includes determining an overlap of valves by opening a supercharged non-fuel-containing air inlet valve and closing an exhaust valve before the exhaust phase of an engine cylinder and in the vicinity of the top dead center (TDC), actuating a blocking means for blocking a supercharged non-fuel-containing air intake means to admit supercharged air flowing in the supercharged non-fuel-containing air intake means into a chamber to scavenge residual burned gases when a pressure of the supercharged non-fuel-containing air is greater than a pressure of the exhaust gases, and actuating the blocking means to shut off the supercharged air flowing from the supercharged non-fuel-containing intake means into the chamber when pressure of the supercharged non-fuel-containing air is less than pressure of the exhaust gases.

Abstract: A method for controlling the air-fuel ratio of an internal combustion engine operating with alternating intake valves is presented. According to the method, engine air-fuel ratio can be adjusted by changing valve timings or fuel during a cylinder cycle.

Abstract: The invention relates to an internal-combustion engine, notably an indirect-injection supercharged engine, that can run with a burnt gas scavenging stage, comprising at least a cylinder (10) including a combustion chamber (12), non-carbureted air intake passage (16) with an air intake valve (24), carbureted air intake passage (14) with a carbureted air intake valve (22), burnt gas exhaust passage (28) with an exhaust valve (32), an exhaust camshaft (36) for controlling the exhaust passage (28), an intake camshaft (44) for controlling the air intake passage (16) and the carbureted air intake passage (14).

Abstract: A fuel injection correction coefficient for a first fuel injection valve and a second fuel injection valve with respect to a second fuel injection proportion in a second combustion is learned (step 107) in each of learning regions based on the fuel supply amount supplied into a cylinder, by carrying out a first combustion whose fuel injection proportion is set to the second fuel injection proportion, in the operation region of the second combustion (step 106).

Abstract: A light load air delivery system for an internal combustion engine having a cylinder head defining at least one intake port selectively opened by a poppet valve which is biased against a valve seat area of the cylinder head. The light load air delivery system includes an intake duct and a controllable valve. A light load air intake passage operates to communicate intake air from the intake duct to the controllable valve. Additionally, a light load air intake manifold is configured to selectively receive intake air from the controllable valve. A feed passage receives the intake air from the light load air intake manifold and communicates the intake air to the respective one of the at least one intake ports at a point substantially adjacent to the valve seat area. In a preferred embodiment, the light load air intake manifold is integral to said intake manifold.

Abstract: A system for an engine, comprising of a cylinder located in the engine, a first port injector for injecting a first fuel into said cylinder, and a second injector outside said cylinder for injecting a second fuel into said cylinder.

Abstract: The present invention relates to a method of controlling a spark-ignition supercharged internal-combustion engine, notably of gasoline type, comprising at least one cylinder (12) with a combustion chamber (14), at least two intake means (24, 26), at least one fuel injection means (40, 42), at least one exhaust means (28, 30) and an ignition means (52). According to the invention, the method consists in preparing a fuel mixture with a fuel/air ratio greater than or equal to 1, another fuel mixture is prepared with a fuel/air ratio below 1, the two fuel mixtures are fed into the combustion chamber so as to obtain a part (C1) of this chamber containing a fuel mixture with the fuel/air ratio greater than or equal to 1 and the remaining part (C2) of the chamber containing the fuel mixture with the fuel/air ratio below 1.

Abstract: An intake air amount controlling apparatus of an engine is provided. The apparatus comprises an intake manifold that is branched from an intake manifold collecting portion of the engine. The intake manifold communicates with an intake port of a cylinder head of a corresponding cylinder. The apparatus further comprises a throttle valve in the intake manifold of the cylinder and a throttle bore provided in the intake manifold. The throttle bore has a curved surface. The throttle valve rotates such that one half of the throttle valve contacts with the curved surface of the throttle bore until the throttle valve reaches a predetermined opening degree. Thus, an air flow via the one half of the throttle valve is prevented from entering the intake port. An air flow via the other half of the throttle valve is allowed to enter the intake port.

Abstract: With reference to FIG. 1, the present invention relates to an internal combustion engine comprising: a combustion chamber (10); first (A) and second (B) inlet valves controlling flow of air into the combustion chamber, first (C) and second (D) exhaust valves; and first (16) and second (18) turbochargers. The first turbocharger (16) is connected to the first inlet valve (A) and the second turbocharger (18) is connected to the second inlet valve (B). The first turbocharger (16) is connected to the first exhaust valve (C) and receives only combusted gases expelled via the first exhaust valve (C). The second turbocharger (18) is connected to the second exhaust valve (D) and all combusted gases expelled via the second exhaust valve flow to the second turbocharger (18) without passing through the first turbo-charger (16).

Abstract: The present invention relates to an indirect-injection internal-combustion engine, notably a supercharged engine, in particular of spark-ignition type, that can run according to a burnt gas scavenging mode or to a conventional mode, comprising at least one cylinder (10) with a combustion chamber (12), at least two air intake means (14, 16), one (14) of the means being a burnt gas scavenging intake means and the other (16) being a fuel injection intake means. The means comprising each a pipe (18, 20) controlled by an intake valve (22, 24), at least one burnt gas exhaust means with an exhaust valve (34) associated with an exhaust pipe (36) and at least one fuel injection means (26).

Abstract: An apparatus and method for controlling charge motion in the air intake manifold includes a barrel-style valve rotatably mounted in the lower air intake manifold between the linearly arranged set of air inlets and the first and second sets of laterally offset air outlets which branch to the first and second cylinder banks, respectively. The barrel valve includes a plurality of openings and is rotatable between a fully open position wherein the plurality of openings are in alignment with the respective air inlets and outlets in the lower manifold allowing substantially unimpeded airflow therethrough, and fully closed position wherein the plurality of openings are substantially fully out of alignment with the respective air inlets and outlets substantially preventing air flow therethrough while allowing air flow through an air bypass formed adjacent to each air inlet and outlet pair.

Abstract: Fuel injection technology of an internal combustion engine is configured in such a manner that in a case where in inlet pipe interior of the engine is partitioned by a rectifying plate into upper and lower flow paths, a flow velocity at a center of the flow path on an upper side, and at a center of the flow path on a lower side is increased. Consequently, a flow velocity distribution of air in a cylinder diametrical direction of a valve head of an inlet valve becomes a peak value on both sides of the valve head center. Therefore, by impinging most of the injected fuel spray upon both sides of the center of the valve head, vaporization of the fuel spray can be performed with good efficiency.

Abstract: In an internal combustion engine includes an intake valve port that opens into a combustion chamber on one side of a plane containing the axis of a cylinder bore. An exhaust valve port opens into the combustion chamber on the other side of the plane. A spark plug has a tip end that fronts a substantially central portion of the combustion chamber. The spark plug is disposed between the intake valve and the exhaust valve. In order to restrain the blow-by of an unburned fuel-air mixture, and to suppress the bulging of the cylinder head to the intake system side, the operation axis of an intake valve is set to be substantially parallel to the axis of the cylinder bore. In addition, one side surface of a cylinder head is formed to be substantially parallel to the axis of the cylinder bore.

Abstract: A variable geometry intake manifold for an internal combustion engine; the intake manifold presents: at least one intake pipe which connects the intake manifold to at least one cylinder of the internal combustion engine; and a choking system to vary the geometry of the intake manifold and comprising at least one choke valve provided with a choke body, which is arranged within the intake pipe and is turnably mounted about an axis of rotation; the choke valve integrates therein a pair of mechanical stoppers, which respectively determine the location of an active position and of a home position of the choke body.

Abstract: A windage tray apparatus is provided and is configured to be mountable within a crankcase at least partially defined by an engine block of an internal combustion engine. The crankcase has a first bay and a non-adjacent second bay. The internal combustion engine has a crankshaft rotatably supported within the crankcase. The windage tray includes a tray member and a passage at least partially defined by said tray member and in communication with the first bay and the non-adjacent second bay. The passage is operable to allow gas transfer between the first bay and the non-adjacent second bay to reduce the motoring friction of the internal combustion engine. An internal combustion engine incorporating the disclosed windage tray apparatus is also provided.

Abstract: The invention relates to an invention combustion engine comprising a cylinder head (1) with at least one inlet port (4) and at least one injection device (6) per cylinder (2), which extends into the combustion chamber. In order to reduce wear of the injection device while preventing depositions in the region of the injector pocket, the top wall (22) of the combustion chamber is provided with an injector pocket (7) in the area of the mouth (6a) of the injection device (6). Preferably, at least one scavenging duct arrangement (10) extends into the injector pocket (7).

Abstract: An internal combustion engine is provided that includes a combustion chamber; a secondary air passage located above the combustion chamber; an exhaust passage that communicates with the combustion chamber; and a water jacket that is located between the exhaust passage and the secondary air passage.

Abstract: An apparatus for minimizing spark-knock within a combustion chamber of a spark-ignition internal combustion engine, whereby a control vane mounted inside the intake runner is arranged to direct a fuel-air charge to a region inside the combustion chamber where spark-knock has been empirically determined to occur.

Abstract: A homogeneous charge compression ignition internal combustion engine capable of reliably reducing flame noise at a time of high-load operation is provided. The engine includes an injector which injects a liquid hydrocarbon fuel to an intake port, and an injector which directly injects an alcohol fuel into a combustion chamber. The liquid hydrocarbon fuel is distributed to an outer peripheral side of the combustion chamber, and the alcohol fuel is distributed to a central portion. The engine includes two intake valves, and divides an intake stroke into a period in which one of the intake valves is stopped and a fuel-gas mixture is flown, and a period in which the both of the intake valves are operated and the flow is suppressed, guides the liquid hydrocarbon fuel into the combustion chamber during the flow period, and injects the alcohol fuel to the combustion chamber during the flow suppression period.

Abstract: An intake throttle valve is located in an intake passage upstream of first and second intake ports, such that intake air flows into mainly the first intake port to generate a swirl flow when an opening degree of the intake throttle valve is not larger than a predetermined value, and flows into both the first and second intake ports when the opening degree thereof is larger than the predetermined value. Furthermore, first and second fuel injection valves for respectively injecting fuel to the first and second intake ports are controlled to inject fuel from the first fuel injection valve when the opening degree of the intake throttle valve is not larger than about the predetermined value, and to inject fuel from both the first fuel injection valve and the second fuel injection valve when the opening degree of the intake throttle valve is larger than about the predetermined value.

Abstract: An intake control valve of an intake device of an internal combustion engine comprises a given portion defined by an air intake passage that leads to a combustion chamber of the engine through an intake valve; a pivot shaft passing through the given portion; and a valve plate secured to the pivot shaft to pivot therewith within the given portion. The valve plate is pivotal between a close position to close the air intake passage and an open position to open the air intake passage. When the valve plate assumes the close position, the interior of the air intake passage downstream the valve plate is formed with mutually isolated first and second air flows that are separated and oriented to enhance a flow of air/fuel mixture in the combustion chamber.

Abstract: A method of operating an engine having at least one cylinder, the method comprising of directing a first air stream to an intake valve of the cylinder; directing a second, separate air stream to a second intake valve of the cylinder, said second air stream at a higher temperature than said first air stream; operating said first intake valve and adjusting at least one of an opening timing and a closing timing of said first intake valve to adjust engine output; and intermittently operating said second intake valve to maintain said higher temperature of said second air stream.

Abstract: A fuel cell system comprising a plurality of fuel cells combined together to form a fuel cell stack, with the fuel cell stack having an anode side with an inlet for a fuel and an outlet for non-consumed fuel and exhaust gases arising at the anode side as well as a cathode side with an inlet for a gaseous oxidising agent such as air and an outlet for exhaust gases which arise at the cathode side, and a compressor having a compressor inlet and a compressor outlet, the compressor outlet of which is connected to the oxidising agent inlet of the fuel cell stack provided at the cathode side, is characterised in that a gas dynamic pressure wave machine having a driven rotor is provided, with an inlet for exhaust gases arising at the cathode side, an inlet for fresh oxidizing agent, an outlet for oxidising agent compressed by the cathode side exhaust gases and also an outlet for the cathode side exhaust gases being associated with the rotor and with the outlet for the oxidising agent compressed by the cathode side ex

Abstract: A cylinder head for an internal combustion engine wherein intake openings to the cylinder are partly surrounded by a mask formed by a material projection of the top face of the combustion chamber, a contour of the mask having a flat main section of maximum height between an ascending and descending flank and being asymmetrical in a developed view.

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

Abstract: A method for improving engine starting for an engine having a variable event valvetrain is described. According to one aspect of the description, valve timing is adjusted during a start to reduce engine emissions and fuel consumption.

Abstract: A ‘Blackburn Cycle’ or 8 stroke and 4 stroke cycle change piston engine has a separate fuel/air inlet duct and valve in a cylinder where the throttle means admits a small volume, namely less than 10% of the cylinder capacity, needed for a low idling speed. A separate ‘air only’ inlet duct and valve admits alternate ‘air only’ inductions in each cylinder when less than half load is needed. The preferred plug type of throttle can be disc or cone shaped or shaped to substantially fill the volume between the closed throttle and the inlet valve seat. For higher power the throttle moves away from the inlet valve to open the inlet port. Fuel is injected into the small volume between the throttle and the inlet valve where engine heat helps vaporize the fuel without heating a large mass of the inlet air.

Abstract: A method of operating an engine for a vehicle having at least a first cylinder, the method comprising of operating the first cylinder to provide at least one of compression braking and expansion braking by holding one of an intake valve and an exhaust valve of the first cylinder closed while opening, closing, and opening the other of the intake valve and the exhaust valve during a cycle of the first cylinder and during a first vacuum level of an intake manifold upstream of the first cylinder; and operating the first cylinder to provide at least one of compression braking and expansion braking by operating both the intake valve and the exhaust valve of the first cylinder during a cycle of the first cylinder to allow at least some air to flow through the first cylinder during a second vacuum level of the intake manifold.

Abstract: A method for providing supplemental internal air cooling to a multi-cylinder internal combustion engine. The method involves deactivating the fuel injector to one cylinder for a predetermined time period or temperature decrease, based upon engine operating conditions, and then reactivating the fuel injector. This results in cool air being pumped through the fuel-deactivated cylinder by the reciprocating action of the piston therein, which air-cools the walls, piston, and head of that cylinder from the inside. In response to a controlling algorithm in an Engine Control Module, various of the engine fuel injectors may be deactivated and then reactivated sequentially to provide distributed cooling over the entire engine. The invention is especially useful for motorcycle engines having two or more cylinders when the motorcycles are used at low or stop-and-go speeds, such as in parades or other ceremonial functions.

Abstract: An internal combustion engine is provided that includes a combustion chamber, a secondary air passage located above the combustion chamber; an exhaust passage that communicates with the combustion chamber, and a water jacket that is located between the exhaust passage and the secondary air passage.

Abstract: A piston engine (10), in particular in a motor vehicle, has a plurality of cylinders (3) whose combustion chambers (4) are connected to a fresh gas system (5). The fresh gas system (5) has two gas paths, namely a full-load path (9) and a partial-load path (10), for at least one of the cylinders (3), through which the fresh gas (6) can be supplied to the respective combustion chamber (4). To this end, a valve arrangement (11) at the intake end is provided for controlling the fresh gas stream through the gas paths (9, 10) into the respective combustion chamber (4).

Abstract: The invention relates to a method for controlling the opening and closing of the intake valves of an internal combustion engine with a direct fuel injection system, comprising at least one first intake valve and a second intake valve per cylinder, wherein each valve respectively opening or closing a first and second intake duct per cylinder can be controlled independently of the other valve, wherein at least one of the ducts is supplied with fuel and at least one of the other ducts is not supplied with fuel. According to the invention, said method consists in controlling the valve or valves corresponding to the intake ducts supplied with fuel during the time intervals when the injection system does not function. The invention also relates to a system for the application of said method.

Abstract: The invention is concerned with a method of deriving mechanical work from a combustion gas in internal combustion engines and reciprocating internal combustion engines for carrying out the method. The invention includes methods and apparatuses for managing combustion charge densities, temperatures, pressures and turbulence in order to produce a true mastery within the power cylinder in order to increase fuel economy, power, and torque while minimizing polluting emissions.

Abstract: An induction system for a multi valve engine that facilitates operation in a lean burn mode over a large range of speeds and loads by employing a smaller cross sectional branch passages in several induction passages serving a common combustion chamber and a valve arrangement that progressively opens flow first through the branch passages and finally through both the main and branch passages so that maximum power can also be obtained.

Abstract: A V-engine (10) having two banks of cylinders (30) each comprising at least one cylinder (20) and a cylinder head (40) is envisaged, wherein the banks of cylinders (30) each comprise at least one inlet valve (12) and also at least one outlet valve (14) for each cylinder (20), while the at least one inlet valve (12) and the at least one outlet valve (14) are arranged in pairs opposite one another on opposite sides of the cylinder head (10), and each cylinder head (10) and its connections to the other engine components are constructed such that it can be mounted in a first position relative to the respective bank of cylinders (30) and in a position rotated through 180° relative to the first position on the same bank of cylinders (30).

Abstract: In an internal combustion engine includes an intake valve port that opens into a combustion chamber on one side of a plane containing the axis of a cylinder bore. An exhaust valve port opens into the combustion chamber on the other side of the plane. A spark plug has a tip end that fronts a substantially central portion of the combustion chamber. The spark plug is disposed between the intake valve and the exhaust valve. In order to restrain the blow-by of an unburned fuel-air mixture, and to suppress the bulging of the cylinder head to the intake system side, the operation axis of an intake valve is set to be substantially parallel to the axis of the cylinder bore. In addition, one side surface of a cylinder head is formed to be substantially parallel to the axis of the cylinder bore.

Abstract: A method for controlling the output of an internal combustion engine includes opening an intake valve on a cylinder; receiving air from an intake manifold into the cylinder during an intake stroke of a piston in the cylinder; returning excess air from the cylinder back into the intake manifold during the initial portion of the compression stroke of the piston, wherein a quantity of combustion air or air/fuel mixture necessary for a desired engine power output remains in the cylinder; and then closing the intake valve. A control device includes a control camshaft rotatively coupled to the crankshaft having a control cam with lobes that engage the intake valves for holding one or more intake valves open; a cam phaser to vary the phase of the controlled cam relative to the main camshaft; and a cam phase controller linked to the cam phaser, wherein advancing the phase of the control cam increases the power output of the internal combustion engine.

Abstract: An intake and exhaust system for a dual mode HCCI engine, which provides superior intake temperature control and homogeneity for engine operation in SI and HCCI modes, as well as during transition between SI and HCCI modes and vice-versa. The system includes adjusted intake cam movement event lengths for intake valve operation at specified modes of operation. The system further includes at least one cam profile switching device operatively connected to intake and exhaust valves in an engine for controlling event length, maximum lift, and valve opening/closing timings for the intake and exhaust valves. The system yet further includes a bifurcated intake system and camless valve actuators for controlling intake valves for facilitating operation in SI or HCCI modes, as well as transition between SI and HCCI modes and vice-versa.

Abstract: A method to control valve patterns in a cylinder operating in a multi-stroke cylinder mode. Valves are controlled to improve drivability and emissions.

Abstract: Otto cycle internal combustion engine, comprising a cylinder block including at least one cylinder having a longitudinal axis, a piston movable within said cylinder and having a recess open on a head surface of the piston, a head fastened to said cylinder block and having a surface facing the cylinder, three intake valves and two exhaust valves movable along respective rectilinear directions, a combustion chamber delimited at one side by a portion of the surface of the head facing the cylinder and, at the other side, by the surface of said recess of the piston. The directions of motion of the valves are parallel to each other, the surface of the head facing the cylinder is planar and orthogonal to the directions of motion of the valves and the combustion chamber is obtained exclusively in the piston.

Abstract: An air-intake device of an engine for a leisure vehicle, in which at least two air-intake passages are arranged within an engine body of the engine, is disclosed, including an air-intake pipe through which fresh air is supplied to the at least two air-intake passages arranged within the engine body, and a throttle valve openably mounted within a passage of the air-intake pipe. Typically, the air-intake pipe is structured such that the passage has a cross-section of a non-perfect circle shape and an outer periphery of the air-intake pipe has a cross-section of a circle shape with a continuously varying positive curvature. Typically, the throttle valve has a valve disc of a non-perfect circle shape conforming to the shape of the cross-section of the passage of the air-intake pipe.

Abstract: A homogeneous charge compression ignition internal combustion engine capable of reliably reducing flame noise at a time of high-load operation is provided. The engine includes an injector 12a which injects a liquid hydrocarbon fuel to an intake port 23, and an injector 12b which directly injects an alcohol fuel into a combustion chamber 21. The liquid hydrocarbon fuel is distributed to an outer peripheral side of the combustion chamber 21, and the alcohol fuel is distributed to a central portion. The engine includes intake valves 25a and 25b, and divides an intake stroke into a period in which the intake valve 25a is stopped and a fuel-gas mixture is flown, and a period in which the intake valves 25a and 25b are operated and the flow is suppressed, guides the liquid hydrocarbon fuel into the combustion chamber 21 during the flow period, and injects the alcohol fuel to the combustion chamber 21 during the flow suppression period.

Abstract: The operation modes of plural intake valves 7a and 7b provided in one cylinder is independently changed according to the drive region of the internal combustion engine. In the low air amount region, the intake airflow is controlled only with intake valve 7a which operates in the low air amount region and the other intake valve 7b is operated in the medium and high air amount regions.

Abstract: A divider plate for two or more inlet ports provided in a cylinder head of an internal-combustion engine comprises divider portions that divides inside of the two or more inlet ports along an intake air flow, a side cast-in insert portion provided on at least one side portion located in a direction perpendicular to that of the intake air flow, that is enclosed by molten metal during casting of the cylinder head, an inner cast-in insert portion that is provided between the divider portions, that is enclosed by the molten metal during the casting of the cylinder head, and an inner accelerator formed in the inner cast-in insert portion, accelerates coagulation of the molten metal, wherein the inner accelerator has at least one of a plurality of holes, a concave portion, a convex portion, and a concave-convex portion, or a combination of a hole and a concave portion, a convex portion or a concave-convex portion.