Abstract: An air-assisted jet flame ignition device includes a housing, a fuel-air premixing unit, and a prechamber. The fuel-air premixing unit includes a fuel injector, an air injection valve, a premixing sleeve, a premixing sleeve inner core placed in the premixing sleeve, and a fuel injector fastening bolt. An inner wall surface of the premixing sleeve and an outer wall surface of the premixing sleeve inner core form a premixing sleeve inner cavity. An inner wall surface of the premixing sleeve inner core, a lower end surface of a nozzle of the fuel injector, and an upper end surface of an air inlet of the air injection valve form a premixing cavity. The premixing cavity coupled to the premixing sleeve inner cavity via a through hole on the sidewall of the premixing sleeve inner core. A prechamber nozzle is fixedly coupled to the lower part of the housing.

Abstract: A piston for an internal combustion engine includes a piston bowl. The piston bowl has a half section profile that includes a bowl entry extending radially from the longitudinal piston center axis, a first bowl recess extending radially from the bowl entry and defining a bowl depth and a first radius of curvature, a second bowl recess extending radially from a first bowl recess to an end perimeter surface and defining a second radius of curvature, a bowl lip defined by the first bowl recess and the second bowl recess, and a bowl edge defined by the second bowl recess and the end perimeter surface. The first bowl recess further defines a first bowl recess exit angle at the bowl lip. The second bowl recess further defines a second bowl recess exit angle at the bowl edge.

Abstract: An internal combustion engine may include a first piston reciprocatingly disposed in a first cylinder, a combustion chamber fluidly coupled with the first cylinder, and an ignition source at least partially disposed within the combustion chamber. An intake valve may provide selective fluid communication between an intake system and the combustion chamber, and an exhaust valve may provide selective fluid communication between an exhaust system and the combustion chamber. A second piston may be reciprocatingly disposed within a second cylinder. A crankshaft may be coupled with the first piston and the second piston for rotational motion associated with reciprocating movement of the first piston and the second piston.

Abstract: An electronic fuel injection type diesel engine enables reduction in engine size. The electronic fuel injection type diesel engine is provided with: a combustion chamber inside a cylinder; a fuel injection chamber inside a cylinder head; a fuel injector that injects liquid fuel into the fuel injection chamber; a fuel accumulation unit that accumulates the liquid fuel injected from the fuel injector; and an electronic control unit that controls a timing and an amount of injection of the liquid fuel.

Abstract: A feed and ignition device for a gas engine has an injector for the direct blowing-in of a combustion gas into a combustion chamber of the gas engine. The device also has a pre-combustion chamber into which a fuel can be introduced and a plurality of overflow openings distributed in the peripheral direction of the injector over the periphery of the feed and ignition device via which the pre-combustion chamber can be directly connected fluidically to the combustion chamber. A spark ignition device ignites a fuel-air mixture including at least the fuel introduced into the pre-combustion chamber. The pre-combustion chamber, the overflow openings, and the spark ignition device are formed by a first structural unit and the injector is formed by a second structural unit formed separately from the first structural unit.

Abstract: A precombustion chamber gas engine includes a main-chamber forming portion forming a main combustion chamber, a precombustion-chamber forming portion forming a precombustion chamber communicating with the main combustion chamber via a plurality of nozzle holes, and an ignition device disposed in the precombustion chamber and having an ignition portion spaced from a main chamber central axis of the main combustion chamber at a predetermined distance. In a plan view, the precombustion chamber has a near-ignition region including the ignition portion and a far-ignition region opposite to the near-ignition region separated by a borderline passing through a precombustion chamber central axis of the precombustion chamber and perpendicular to a straight line passing through the precombustion chamber central axis and the ignition portion.

Abstract: A combination for an opposed-piston engine includes an intake piston and an exhaust piston, each with a top land height. The intake piston top land height is less than the exhaust piston top land height.

Abstract: The present invention provides a rapid gas release system for rapidly regulating and burning compressed, combustible gas as a safety precaution to prevent explosion, while also exhausting any heat produced by the burning. This is accomplished through a combustor, a regulator in fluid connection with the combustor and a tank, a controller, and a cooling chamber. The tank contains the compressed combustible gas, which is released into the combustion chamber and burned, then exhausted to the cooling chamber.

Abstract: A piston and combustion chamber including piston crown grooves extending from the combustion bowl, promoting swirl and mix within the compressed atmospheric air/gases made up of 78% nitrogen along with 20% oxygen locked in the bowl into an ideal mix with the introduced fuel forming into an ideal charge trapped in the bowl of the piston crown improve thermal efficiencies by overcoming erratic, incomplete and improper combustion resulting in lower emissions that can prevent environmental damages due to pollution from UHC, CO, NOx, soot with the least carbon dioxide formations when using carbon rich fuels such as diesel engine operations under full load.

Abstract: A combustion engine and a method of operating the combustion engine are disclosed. The method comprises supplying a charge gas to the combustion chamber through an intake port; discharging a cryogenic fuel in a liquid state from a fuel injector in fluid communication with the combustion chamber; closing an intake valve to close the combustion chamber; and actuating a piston during a compression cycle to compress the charge gas and the cryogenic fuel. At least a portion of the cryogenic fuel evaporates in the closed combustion chamber.

Abstract: Embodiments of the disclosure pertain to a method for monitoring a heat exchanger unit that may include the steps of: associating a monitoring module with an airflow side of the heat exchanger unit; operating the monitoring module whereby a microcontroller performs tasks related to data acquisition, data comparison, and providing an indication; and taking an action based on the indication. The monitoring module includes an at least one sensor proximate to the airflow side; a logic circuit in operable communication with the at least one sensor, and further comprising the microcontroller.

Abstract: A control apparatus for an internal combustion engine having an air flow control valve which changes intake air flow achieves the stratified lean combustion, in place of the homogeneous lean combustion, in a specific combustion stroke of a specific cylinder, when it switches the opening of the air flow control valve, if all of or a part of a specific intake stroke overlaps with a switching period of the air flow control valve, the specific combustion stroke following the specific intake stroke of the specific cylinder. As a result, even when the opening of the air flow control valve is changed, it is possible to make combustion stable. Thereby, the occurrence of torque fluctuation is suppressed.

Abstract: Auxiliary chamber type internal combustion engine has a main combustion chamber and an auxiliary chamber having an injection port through which the main combustion chamber communicates. The auxiliary chamber has a passage sectional area which is smoothly decreased toward the injection port. Further, the engine has a fuel injector injecting a fuel into the auxiliary chamber; an ignition plug igniting the fuel in the auxiliary chamber; and a swirl generating portion swirling a gas in the auxiliary chamber. The swirl generating portion swirls only the gas flowing into the auxiliary chamber from the main combustion chamber.

Abstract: An internal combustion engine includes a pre-chamber assembly including a wall having an internal surface opposite an external surface, the internal surface of the wall defining a combustion pre-chamber and at least one orifice extending to an aperture through the external surface of the wall; a block having an internal surface defining a bore therein; a piston disposed within the bore and configured for reciprocal translation within the bore, the piston, the bore, and the external surface of the wall at least partly defining a main combustion chamber, and the combustion pre-chamber being in fluid communication with the main combustion chamber via the at least one orifice; an energy source operatively coupled to the combustion pre-chamber; and an exhaust gas recirculation (EGR) valve fluidly coupled to the combustion pre-chamber and an exhaust conduit of the internal combustion engine.

Abstract: An internal combustion engine diagnostic device and an internal combustion engine diagnostic method identify an abnormal cylinder having an abnormal air-fuel ratio among a plurality of cylinders during the operation of an internal combustion engine. The internal combustion engine diagnostic device comprises: an air-fuel ratio control unit for changing the air-fuel ratio in a stepwise manner by controlling a fuel injection amount adjusting means that adjusts the fuel injection amount of each of the plurality of cylinders; and an abnormal cylinder identification unit for identifying an abnormal cylinder on the basis of the relationship between each air-fuel ratio changed in a stepwise manner and the number of misfires occurring in the plurality of cylinders, the number being counted by a misfire counter for each air-fuel ratio changed in a stepwise manner.

Abstract: A piston for an internal combustion engine is disclosed. The piston may have a piston skirt with a center axis. The piston may also have a piston crown disposed adjacent a top of the piston skirt. The piston crown may have a diameter D. The piston crown may have a piston crown margin of width b extending in a circumferential direction. The piston crown may also have a piston trough with a depth t. The piston trough may have a piston trough wall with a base diameter. The piston trough may also have at least one recess with a height h. The height h parallel to the direction of the center axis may satisfy the following requirement: 0.2 t<=h<=t.

Abstract: A piston engine intakes, at the compression stage, lean gas-air mixture from a cylinder to the ignition chamber. The residual gases are at 500° C. to 700° C., and are composed of: carbon dioxide 6.7% to 5.6%, oxygen 6.6% to 8.8%, water vapor 12.8% to 19.8% with the air excess factor 1.5 to 1.8, are preserved in the ignition chamber and are used for initiating, at the contact, and mixing with the gas-air mixture, the reactions of combined conversion of the lowermost alkanes (methane, ethane, propane, butane, etc.), into hydrogen and carbon monoxide; intensifying reactions of combined conversion in the compression cycle, by increasing pressure and, therefore, temperature of the gas-air mixture in the cylinder and in the ignition chamber, up to 5-5.5 MPa and 500-600° C., at the moment of the spark. The ignition chamber can be made of catalytic material, e.g., nickel heat-resistant steel.

Abstract: An ignition system for an internal combustion engine having at least one combustion chamber where the ignition system includes a housing, an ignition device, an injector, and a pre-chamber having a nozzle disposed spaced from the proximal portion of the pre-chamber. The igniter portion of the ignition device and the nozzle of the injector are operatively supported in the proximal portion of the pre-chamber and disposed flush therewith. The igniter portion ignites the fuel in pre-chamber such that partially combusted pre-chamber products are forced through orifices in the pre-chamber nozzle and extinguish, but dispersed through the combustion chamber so as to ignite the main fuel charge therein.

Abstract: A spark plug of internal combustion engine is disclosed. The spark plug includes: a main body having main thread on lower outer side; an insulator mounted in a hollow portion of the main body; a ground electrode to correspond to a central electrode extending from the lower end of the terminal rod; a primary combustion chamber forming shell having female thread to be screw-coupled with the main thread, male thread to fix a combustion chamber, and an ejection hole; the primary combustion chamber formed between the main body and the primary combustion chamber forming shell and having changeable volume; and a heat exchange member disposed between the main body and the insulator to exchange heat caused by flame and to block leak of volatile gas; wherein the main ejection hole has a single main ejection hole and at least two auxiliary ejection holes formed around the main ejection hole.

Abstract: An internal combustion engine includes one main combustion chamber for the combustion of a first combustion mixture, one pre-combustion chamber for each respective main combustion chamber for the combustion of a second combustion mixture, a first fuel gas mixer for providing the first combustion mixture, a second fuel gas mixer for providing the second combustion mixture, an air feed line and a synthesis gas feed line, a first mixture line connected to the first fuel gas mixer and the main combustion chamber, and a second mixture line connected to the second fuel gas mixer and the pre-combustion chamber. The first fuel gas mixer is connected to the synthesis gas feed line for the admixing of synthesis gas, and an open or closed loop control device is provided for open or closed loop controlling mixing ratios of fuel, air and synthesis gas in the first combustion mixture and/or second combustion mixture.

Abstract: Disclosed is a combustion chamber of a diesel engine provided with a bowl having a concave shape so that fuel injected from an injector creates a swirl or squishing flow to be mixed with air, and the combustion chamber of the diesel engine includes: a pip protruding from a center of a lower surface of the bowl toward the injector; a lip part protruding from a side surface of the bowl toward the injector; and a main combustion chamber provided on a lower portion of the lip part and a sub combustion chamber provided on an upper portion of the lip part, with the lip part interposed therebetween, in which a surface of the sub combustion chamber is formed in a flat shape or a concave bowl shape to have a depth of the sub combustion chamber of 0.8 mm or lower.

Abstract: Apparatus constituting part of an induction and fuel delivery system for a cylinder of a piston internal combustion engine comprising a small cyclone into which is tangentially discharged a flow of heated air to generate a sustained vortex of high rotational speed; a modulatable fuel injector delivering a flow of atomized fuel into said small cyclone wherein it underdoes flash evaporation and energetic mixing; a delivery duct connecting said small cyclone to the inlet tract of said cylinder wherein said vortex fuel-air mixture is mixed with heated induction air; and means to prevent overheating of said modulatable fuel injector.

Abstract: A technique for improving the cooling performance of a combustion chamber in a combustion power tool is provided. The combustion power tool includes first and second combustion chambers, a partition that separates the first combustion chamber from the second combustion chamber, openings, formed in the partition and communicate the first combustion chamber with the second combustion chamber, and a drive section that moves toward a front end by combustion pressure. The combustion pressure is generated when a flow of flammable gas, which is produced by combustion of the flammable gas in the first combustion chamber propagates to the second combustion chamber through the openings, and burns flammable gas in the second combustion chamber. The combustion gas flows from the first combustion chamber to the second combustion chamber in a direction around a central axis of the second combustion chamber while flowing along an inner wall of the second combustion chamber.

Abstract: A reciprocating internal combustion engine. The present invention improves the spark ignition facility used by the engine inventions described in patent publications WO2005/052335 and WO2007/080366 by providing a device to ensure reliable spark ignition by protecting the spark plug from malfunction by sooting.

Abstract: A direct injection spark ignition internal combustion engine includes a fuel injector for directly injecting fuel into a cylinder and intensifies a tumble flow using the fuel injected into the cylinder bore at a time near an intake stroke bottom dead center during homogenous combustion. The thrust force of the fuel injected from the fuel injector is set to intensify the tumble flow based on at least one of the state of the combustion chamber, the temperature of the injected fuel, and the orientation of the injection hole.

Abstract: An internal combustion engine, including a main combustion chamber serving as a main combustion chamber, an auxiliary combustion chamber adjacent to the main combustion chamber and smaller in capacity than the main combustion chamber, and a partition wall between the main combustion chamber and the auxiliary combustion chamber, the partition wall including an injection hole by which the main combustion chamber and the auxiliary combustion chamber communicate. A fuel supply device supplies fuel to the main combustion chamber and the auxiliary combustion chamber. A mixture forming device forms a mixture of air and the supplied fuel in the main combustion chamber, away from the partition wall before ignition. An ignition device ignites the fuel in the auxiliary combustion chamber, propelling an ejecting torch flame into the mixture of air and fuel in the main combustion chamber through the injection hole, thereby burning the mixture of air and fuel in the main combustion chamber.

Abstract: A high thermal efficiency lean-burn spark- ignition two or four stroke engine operable unthrottled suitable for vehicles using gasoline. It uses an indirect combustion chamber and a transfer orifice with or without shaping of the combustion chamber to produce a jet of air moving in helical swirl motion around the chamber during the compression stroke. Fuel is injected into the chamber aimed into the air jet to assist rapid vaporization. The position and orientation of the fuel injector ensures that fuel arrives near the spark plug even under idling conditions and the helical swirl flow ensures the stratification of the ignitable mixture formed near the plug. The compression ratio of the engine can also be variable.

Abstract: A tube for directing fluid along a path that includes a bend. The tube comprising a conduit having a first aperture, a second aperture, and a bend portion adjacent the second aperture. An outer bend surface is integrally formed as part of the conduit to at least partially define the second aperture. An insert includes at least a portion of an inner bend surface and is disposed at least partially within the second aperture such that the outer bend surface and the inner bend surface cooperate to at least partially define the bend.

Abstract: A high thermal efficiency lean-burn spark-ignition two or four stroke engine operable unthrottled suitable for vehicles using gasoline. It uses an indirect combustion chamber and a transfer orifice aligned to produce a jet of air moving in helical swirl motion around the chamber during the compression stroke. Fuel is injected into the chamber aimed into the air jet to assist rapid vaporization. The position and orientation of the fuel injector ensures that fuel arrives near the spark plug even under idling conditions and the helical swirl flow ensures the stratification of the ignitable mixture formed near the plug.

Abstract: A gas combustion-powered apparatus has a first chamber, a rotatable fan in the first chamber, an ignition source in operable relationship to the first chamber to ignite a combustible gas, and a second chamber. A communication passage is located downstream of the fan between the first chamber and the second chamber, and is constructed and arranged for enabling passage of an ignited gas jet from the first chamber to the second chamber. An intake port is located on a wall of the first chamber upstream of the fan, and a bypass port, separate from the communication passage, is located on the wall of the first chamber downstream of the fan.

Abstract: A gas combustion-powered apparatus has a first chamber, a rotatable fan in the first chamber, an ignition source in operable relationship to the first chamber to ignite a combustible gas, and a second chamber. A communication passage is located downstream of the fan between the first chamber and the second chamber, and is constructed and arranged for enabling passage of an ignited gas jet from the first chamber to the second chamber. An intake port is located on a wall of the first chamber upstream of the fan, and a bypass port, separate from the communication passage, is located on the wall of the first chamber downstream of the fan.

Abstract: The present invention provides a piston for a diesel engine that reduces emissions generated during the combustion of fuel in a combustion chamber and a head that allows more air to flow into and out of the combustion chamber. The piston includes an igniter that ignites fuel injected into the combustion chamber and a piston bowl. The piston bowl agitates air in the combustion chamber to quickly mix the fuel and air before the igniter ignites the fuel and to reduce carbon build-up from unburned fuel in the combustion chamber. By igniting the fuel shortly after it is injected into the combustion chamber, the igniter reduces the time between injection and combustion of the fuel in the combustion chamber. Thus, the amount of NOx produced during combustion is reduced. Furthermore, injection of the fuel can commence when the piston is closer to top dead center and thus more power can be generated.

Abstract: A swirl chamber used in association with a combustion chamber for diesel engines, includes a pair of sub-nozzle holes on the opposite sides of a main nozzle hole to supply a secondary air into the swirl chamber, the sub-nozzle holes being positioned such that the secondary air ejected therethrough is fully utilized for the combustion in the swirl chamber, thereby securing the complete combustion and the reduction of environmental contaminants such as NOx and fumes.

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 improved combustion system particularly for a larger type diesel engine featuring a prechamber with a generally cup-shaped bottom tip portion facing the engine's main combustion chamber and with a central transfer passage substantially aligned with the centerline of the prechamber and a plurality of additional transfer passages circumferentially arranged about the centerline of the prechamber. The improved complete combustion system uses a piston with a deep bowl formed in the piston crown into which the central transfer passage directs a strong direct charge of products of combustion from the prechamber.

Abstract: A direct-injection spark-ignited engine is provided that includes a combustion chamber formed between a lower surface of a cylinder head and an upper surface of a piston. An intake and an exhaust valve are respectively disposed in an intake port and an exhaust port. These ports are respectively disposed on each side of the cylinder head. A spark plug is disposed in the cylinder head. A fuel injector directly injects fuel into the combustion chamber. A bowl is formed in the upper surface of the piston for generating a turbulent air flow.

Abstract: A direct-injection spark-ignited engine is provided that includes a combustion chamber formed between a lower surface of a cylinder head and an upper surface of a piston. An intake and an exhaust valve are respectively disposed in an intake port and an exhaust port. These ports are respectively disposed on each side of the cylinder head. A spark plug is disposed in the cylinder head. A fuel injector directly injects fuel into the combustion chamber. A bowl is formed in the upper surface of the piston for generating a turbulent air flow.

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 engine comprises one or more pairs of first and second cylinders, the first cylinder having a larger swept volume than the second cylinder and respective first and second pistons reciprocable in the cylinders. The second piston has a drive stem and divides the second cylinder into a first volume containing the drive stem of the second piston and a second volume between the two pistons. An air inlet and an exhaust outlet are provided for the first cylinder. A common combustion space is formed between the pistons when the pistons are substantially at their inner dead center positions, the combustion space comprising the second volume. A transfer means enables gas flow between the first volume and the combustion space whilst an inhibiting means inhibits the movement of a substantial amount of fuel/air mixture from the first volume into the second volume until toward the end of the compression stroke of the second piston.

Abstract: To accelerate a combustion within an entire combustion chamber including the vicinity of an opening portion for air suction to thereby make uniform a flame propagation in a combustion chamber structure for an internal combustion engine, and to provide a technology for preventing the generation of knocks, a longitudinal sectional shape of a top wall surface of the combustion chamber is in the form of a substantially triangular shape in longitudinal section defined and surrounded by a cylinder head, a cylinder and a piston. A projection is provided on a circumferential edge portion of a top surface of the piston, with a surface, facing the top wall surface of the combustion chamber, of the projection being substantially in parallel with the top wall surface of the combustion chamber. A cutaway portion is formed in the vicinity of at least a portion, facing the intake opening portion, of the projection of the top surface of the piston.

Abstract: This invention relates to an in-cylinder injection internal combustion engine. A lower wall of a cylinder head, said lower wall defining an upper wall of a combustion chamber, is configured in the form of a pentroof composed of an intake-valve-side, tilted, lower wall and an exhaust-valve-side, tilted, lower wall. A spark plug is arranged in the vicinity of a top part of the pentroof-shaped upper wall of the combustion chamber. A top wall of a piston, said top wall forming a lower wall of the combustion chamber, is configured in the form of a pentroof having an intake-valve-side, tilted, top wall and an exhaust-valve-side, tilted, top wall formed so that they correspond the intake-valve-side, tilted, lower wall and the exhaust-valve-side, tilted, lower wall of the cylinder head. A recessed portion is arranged in the intake-valve-side, tilted, top wall in the top wall of the piston.

Abstract: A diesel engine using a low evaporativity fuel, and improves the fluidity of the air and fuel by injecting the fuel into a cylinder at the beginning of a compression stroke forming a uniform gaseous mixture, whereby the generation of NO.sub.x is minimized. A swirl chamber is formed in a piston, and a primary chamber by a combustion chamber structure provided in a cavity of a cylinder head. A fuel injection nozzle injects a low evaporativity fuel, such as heavy oil, into the cylinder at the beginning of a compression stroke, disperses the fuel into an air swirl in the cylinder, forms a uniform gaseous mixture of the fuel and air therein, and ignites and burns with the assistance of a glow plug the gaseous mixture entering the swirl chamber through communication ports at the end of the compression stroke.

Abstract: This invention relates to an in-cylinder injection internal combustion engine. A recessed portion (22A) is arranged in a top wall of a piston (22) to promote formation of a vertical swirl so that a flow of inducted air introduced into a combustion chamber (27) of the engine is caused to advance from a lower wall (21A) of a cylinder head (21) of the engine toward the top wall of the piston (22) and then to advance backward from the top wall of the piston (22) toward the lower wall (21A) of the cylinder head (21). A corner of the recessed portion (22A) is formed blunter at an outlet side of the vertical swirl than at an inlet side of the vertical swirl. In the in-cylinder injection internal combustion engine in which fuel is injected directly into the combustion chamber (27), it is possible to achieve inter alia a high gas mileage by allowing a lean air-fuel mixture to undergo stratified combustion and also a high power output when a gas-fuel mixture richer than the lean air-fuel mixture is burnt.

Abstract: In this engine with precombustion chambers, precombustion chambers are formed in pistons, and an air utilization rate in main combustion chambers formed in cylinders is improved, whereby the mixing of air with flames is promoted with a combustion period reduced. In this engine, main communication ports communicating the main combustion chambers and precombustion chambers with each other are formed in the substantially central portions of piston heads, while auxiliary communication ports are formed around the main communication ports so as to extend incliningly toward the circumferences of the cylinders. The fuel injection nozzles provided in a cylinder head are projected into the main communication ports in positions in the vicinity of the top dead centers of the pistons to close the same, and fuel is injected from multi-bored injection ports of the fuel injection nozzles into the precombustion chambers.

Abstract: When viewing in parallel to a cylinder center axis (3), a combustion expanding gas injected from an injection hole (4) is adapted to form a pair of valve recesses (10), (11) located on the opposite sides of an injection axis (12) of the injection hole (4). A pair of valve recesses (10), (11) are formed concavely in a piston top surface (8) so as to be separately disposed on the opposite sides of the injection axis (12) of the injection hole (4). Respective swirl centers (14), (15) of a pair of swirling gas flows (6), (7) are located within the pair of valve recesses (10), (11).

Abstract: This pre-chamber type engine is provided with pre-chambers formed in the cavities in piston bodies, and head plates consisting of a material of a high thermal resistance the thermal expansion coefficient of which is substantially equal to that of the piston bodies and fixed to the piston bodies. The fuel injection nozzles project into the insert bores made in the head plates when the pistons are in positions in the vicinity of the top dead centers. The communication ports formed in the head plates extend in the portions thereof which are around the insert bores diagonally with respect to the axes of cylinders, and are spaced from one another in the circumferential direction thereof.

Abstract: A diesel engine (10) has a pre-combustion chamber (30) with an angled and tapered transfer passage (60) leading to the main combustion chamber (44). The transfer passage (60) is tapered to provide a larger lower end (62) facing the main chamber (44) and smaller upper end (64) facing the pre-combustion chamber (30). Air passing through the passage (60) during the compression stroke undergoes heating and swirling within the pre-combustion chamber. The piston has an upper surface (46) with recessed lobes (20) and (22) and recessed passage area (28). Each recessed lobe functions as a valve pocket for the respective intake valve (32) and exhaust valve (42). The valve pockets are deep enough to provide sufficient valve lifts to allow valve overlap periods comparable with spark ignition gasoline engines without interfering with the piston upper surface (46).

Abstract: A diesel engine (10) has a precombustion chamber (30) with four circumferentially spaced and angled transfer passages (60, 61) leading to the main combustion chamber (44). Each transfer passage (60, 61) is tapered to provide a larger lower end (62) facing the main chamber (44) and smaller upper end (64) facing the precombustion chamber (30). Air passing through the passages during the compression stroke undergoes heating and swirling within the precombustion chamber. The flame front passing from the precombustion chamber to the main combustion chamber are aimed toward the centers (68 and 69) of respective recessed lobes (20 and 22) within piston (18).

Abstract: A diesel engine includes a variable swirl forming mechanism, an exhaust gas recirculation (EGR) control mechanism, and an injection timing control mechanism. The variable swirl forming mechanism forms strong, middle or weak air swirls in a combustion chamber according to engine loads and engine speeds. The EGR control mechanism recirculates a part of exhaust gas to the combustion chamber according to the engine loads and the engine speeds. The injection timing control mechanism advances or retards the injection timing according to the engine loads and the engine speeds.

Abstract: To accelerate a combustion with an entire combustion chamber including the vicinity of an opening portion for air suction to thereby make uniform a flame propagation in a combustion chamber structure for an internal combustion engine, and to provide a technology for preventing the generation of knocks, a longitudinal sectional shape of a top wall surface of the combustion chamber is in the form of a substantially triangular shape in longitudinal section defined and surrounded by a cylinder head, a cylinder and a piston. A projection is provided on a circumferential edge portion of a top surface of the piston, with a surface, facing the top wall surface of the combustion chamber, of the projection being substantially in parallel with the top wall surface of the combustion chamber. A cutaway portion is formed in the vicinity of at least a portion, facing the intake opening portion, of the projection of the top surface of the piston.