Abstract: The present invention relates to a method of controlling an internal-combustion engine comprising at least one cylinder (10) with at least one burnt gas exhaust means (12) including an exhaust valve (16) whose opening/closing is controlled by control means (22) and an exhaust pipe (14) connected to an exhaust line (18, 20), at least two intake means (26, 28) comprising each a valve (32, 36) whose opening/closing is controlled by a dedicated actuating means (46, 48) and a pipe (30, 34). The method, during low load or medium load running of the engine: controls the closed position of exhaust valve (16) and controls one (36) of the intake valves so as to operate it as a burnt gas discharge valve.

Abstract: The present invention relates to a method of controlling an internal-combustion engine comprising at least one cylinder (10) with at least one burnt gas exhaust means (12) including an exhaust valve (16) whose opening/closing is controlled by control means (22) and an exhaust pipe (14) connected to an exhaust line (18, 20), at least two intake means (26, 28) comprising each a valve (32, 36) whose opening/closing is controlled by a dedicated actuating means (46, 48) and a pipe (30, 34). The method, during low load or medium load running of the engine: controls the closed position of exhaust valve (16) and controls one (36) of the intake valves so as to operate it as a burnt gas discharge valve.

Abstract: A method of operation of a four-stroke internal combustion engine having an intake, a combustion chamber coupled to the intake, an exhaust coupled to the combustion chamber and an exhaust recirculation device connecting the exhaust to the intake. The method includes admitting exhaust gas into the combustion chamber which is recirculated by the recirculation device from the exhaust into the intake. Thereafter, a mixture of air and fuel to be combusted is admitted through the intake into the combustion chamber which produces a stratification in the combustion chamber of the mixture of air and fuel and the exhaust gas. The stratified contents of the combustion chamber are then combusted by self-ignition.

Abstract: The present invention is a process for controlling self-ignition in a four-stroke engine comprising variable control of the opening and the closing of the intake and exhaust in the combustion chamber as a function of the engine load. At partial load the invention performs (a) prolonged retention of burned gases in the combustion chamber, and (b) a fresh gas intake period which overall follows the retention period, in order to minimize mixing of the fresh gases with the burned gases and to control the amount of burned gases retained in the combustion chamber.

Abstract: The present invention relates to a process for delivering and for metering additives to the combustion chamber of an internal-combustion engine consuming a known and controlled amount of lubricant, according to which the lubricant consumed comprises at least one additive designed to improve the quality of the combustion in the chamber. In particular, the additive is designed to promote the combustion of an engine working with controlled self-ignition and to obtain operation in a wider speed and/or load range of the engine.

Abstract: The present invention relates to an internal-combustion engine having at least one piston sliding in a cylinder, at least one combustion chamber (4) and a compressed air or gas storage tank (14) connected to a volume compressed by the motion of said piston via a connection means provided with a nonreturn device (16) allowing a gas at a pressure greater than or equal to that of the compressed volume to be stored in said tank (14). According to the invention, the gas under pressure present in said tank (14) fulfills a purpose other than that related to the feeding of the combustion chamber (4).

Abstract: The present invention relates to a two-stroke engine comprising at least:a cylinder (111) in which a piston (112) moves and one end of which communicates with a pump crankcase (115) crossed through by the crankshaft (114) of the engine,a capacity under pressure (87) opening at one end into the combustion chamber (113) of the cylinder (111), at least one valve (86) ensuring an intermittent sealing between the chamber (113) and the capacity (87),a means (88) intended for carburetting the gas passing in said capacity (87),a means for controlling the opening of said valve (86) comprising a supple membrane (89) separating two chambers (95a, 95b) and connected to the rod of the valve.The engine according to the invention further comprises a liking means (92) between one (95b) of said chambers and the pump crankcase (115) of said cylinder, allowing notably the opening of the valve (86) to be activated as soon as possible when the pressure P.sub.B in the chamber (95b) becomes lower than the pressure P.sub.

Abstract: The present invention is an air-blast fuel injection two-stroke engine comprising at least one cylinder (1) in which moves a piston (2) defining a combustion chamber (14) and a pump crankcase (5) forming a continuation of the combustion chamber and separated therefrom by the piston (2), at least one main air inlet (7) in the pump crankcase that can be equipped with a first nonreturn device (6), a device for introducing the fuel mixture at a given pressure, comprising a mechanism (20) for opening and for closing a port (12) for introducing the fuel mixture into the combustion chamber (14), a container (15) connected to the introduction port (12) and containing the fuel mixture under pressure. The engine further comprises a mechanism (30-34) for sucking and introducing the fuel mixture under pressure into the container.

Abstract: The present invention relates to a two-stroke internal-combustion engine depollution process including a separate and deferred delivery of fuel in relation to the air used to scavenge the burned gases, and having an advanced ignition delay with respect to optimal advanced ignition. According to the invention, the delay is such that it allows the exhaust gas temperature to increase and to create a post-oxidation of the unburned hydrocarbons contained in the exhaust gases, the post-oxidation sparing the use of a specific catalyst at the exhaust. Preferably, the delay is achieved in a stabilized-speed operating range of the engine.

Abstract: A catalyst is integrated into a cylinder block of an engine and positioned near at least one exhaust port thereof. A separation wall is provided for dividing the exhaust flow into two branches, one of which contains the catalyst. A control device responsive to at least one engine parameter selectively seals one of the branches such that exhaust is either passed through the catalyst or around the catalyst. A coolant passage is provided adjacent the catalyst to prevent overheating.

Abstract: A device for controlling a pneumatic injection of a carbureted mixture into a combustion chamber of a two stroke internal combustion engine, with the device including a compressed gas supply pipe adapted to be communicated with the combustion chamber of a cylinder by an intermittent sealing element, and a fuel metering device opening into the compressed gas supply pipe. A selective sealing element is arranged in the compressed gas supply pipe upstream from the intermittent sealing element and from the fuel injection device for controlling all carbureted mixture conveyed into the compressed gas supply pipe and used for pneumatic injection according to operating conditions of the internal combustion engine.

Abstract: A two-stroke engine comprising a crankshaft rotating around a first axis of rotation and having at least one balancing mass, a controller for controlling feeding of at least one combustion chamber of the engine. A second shaft is rotatable around a second axis of rotation parallel to the first axis of rotation and is rotatably driven by the crankshaft. At least one balancing mass is connected in rotation to the controller so as to achieve a first order balancing of the reciprocating masses of the engine. A pneumatic fuel injection system, utilizing a portion of an air charge of the engine, sprays fuel into the combustion chamber at predetermined times of a working cycle, and a counter rotating drive of the pneumatic injection controller means by the crankshaft is achieved by a two-space toothed belt.

Abstract: A two-stroke engine which includes a cylinder in which a piston moves with a device being provided for allowing the feeding of a charge under pressure to the cylinder and at least two inlet ports in a well of the cylinder. The engine includes a device for selectively sealing a section of flow of the inlet port in accordance with at least one working parameter of the engine The device for selectively sealing may, for example, include a rotary plug placed opposite the inlet ports, with the plug including at least two through openings.

Abstract: A two-stroke engine comprising at least one cylinder having a combustion chamber, an exhaust duct connected to the combustion chamber, at least one duct for the intake of fresh gas compressed by a compression device for delivering said fresh compressed gas, at least a first rotary valve opens and closes the exhaust duct and at least a second rotary valve feeds fluid into the combustion chamber.

Abstract: An engine including at least one cylinder in which a piston moves delimiting a combustion chamber and a housing, with at least one opening for allowing fresh air to enter the combustion chamber and one pneumatic injection device. The fuel is atomized or sprayed and injected into the chamber by using a compressed gas. For small engine charges, a compressed gas is used, with the compressed gas being derived solely from the chamber or the housing of the cylinder of the engine, and for high engine charges, another compressed gas is used derived from a source outside the cylinder. The source outside the chamber may include a mechanical compressor driven by one of a two-stage engine or a turbocompressor.

Abstract: A two cycle engine with pneumatic injection, with the engine including a cylinder, a crankcase communicating with one end of the cylinder, and at least one transfer passageway joining the crankcase to the cylinder. A fuel injector is supplied with compressed air by a container connected to the crankcase and a flow restriction arrangement for restricting the flow of gases is disposed in the transfer passageway. The opening and closing of the flow restriction arrangement is controlled and regulated as a function of at least one engine operating parameter, with the overall result being an improvement in a quality of the fuel injection into the two cycle engines.

Abstract: A method and device for introducing carburetted mixture under pressure into a first cylinder of an internal combustion engine comprising at least one other cylinder having a crankcase pump. The device for introducing carburetted mixture comprises a connecting duct between the crankcase and the first cylinder and an angular non zero shift exists between the cycle of each of the cylinders.

Abstract: Scavenging a cylinder of an engine with fuel-free fresh air and injection with atomized liquid fuel by a pressurized gas are accomplished independently, at specific moments during by the operating cycle of the engine. The fuel is atomized and injected into the cylinder by gases tapped from cylinder of the engine. The injection device can comprise a reservoir in which the gases tapped from cylinder are stored. The gases can be tapped from cylinder by a pneumatic injector when the valve opens.

Abstract: A two-stroke engine having at least one cylinder in which a piston is movably accommodated, with a crank case communicating with one end of the at least one cylinder. Air is admitted to the crank case and at least one pipe admits unmixed air from the crank case to a cylinder transfer port. The fuel is pneumatically injected into the cylinder by way of a pneumatic injector and a pipe connected to the crank case by a valve and forming a volume of pressurized air connected to the pneumatic injector supplies the pneumatic injector with pressurized air for atomizing the fuel. An exhaust pipe is connected to the at least one cylinder by an exhaust port located in a position offset in a direction of travel of the piston with respect to the cylindrical transfer port of the cylinder.

Abstract: An internal combustion 2-stroke engine having at least one combustion chamber equipped with a delayed fuel supply system opening into a cylinder head. A wall of the cylinder has at least one exhaust port situated in the vicinity of a first referernce point through which passes a first axial plane of the cylinder or exhaust plane and at least one intake port situated in the vicinity of a second reference point, or intake reference point. A plane perpendicular to the exhaust plane and containing the axis of the cylinder defines two accommodation zones in the cylinder with the first accommodation zone, complementary to the second one, containing the reference point of the exhaust port, and the supply system is situated in the second accommodation zone.