Abstract: The invention relates to a device for accelerating a turbocharger unit at low speeds of a reciprocating engine (1) operating with a four-stroke cycle and including at least one cylinder (1a) provided with at least one admission valve (2) connected to an admission manifold (3) and at least one exhaust valve (4) connected to an exhaust manifold (5), said turbocharger unit comprising at least one turbocharger (10) comprising an air compressor (11) feeding the admission manifold (3) and a radial-flow turbine (12) fed by the exhaust manifold (5) and driving the compressor (11). The device includes an aerodynamic ejector (20) taking a driving flow from the exhaust gas of the engine (1) and a driven flow delivered by the compressor (11) and forming a mixed flow that feeds the turbine (12) of the turbocharger unit (10).

Abstract: The invention relates to a reciprocating internal combustion engine having at least one cylinder (1a) provided with at least one admission valve (2) and at least one exhaust valve (3). The pulsating stream of first gas is exhausted from the cylinder (1a) via an exhaust duct (5) fitted with an expansion nozzle leading tangentially to a peripheral wall of a circularly symmetrical centrifuge chamber (10) and perpendicularly to the axis of said chamber. The centrifuge chamber (10) communicates with a duct for feeding the turbines of a turbocharger unit (30) via an annular radial diffuser.

Abstract: This device is designed for a piston which is designed to move in alternating linear movement parallel to the axis of a chamber divided by the piston into a high pressure volume and a low pressure volume, and is of the type comprising: a circular cylindrical sliding surface bounding the chamber, an annular groove provided in the piston which is coaxial with the sliding surface and open towards the sliding surface, and a closed resilient sealing ring housed in a leak tight manner in the groove and intended to make sealing contact with the sliding surface. According to one aspect of the invention the ring is designed to determine the size of a lubricating oil film between the ring and the sliding surface to a limit lubricating thickness preferably from 0.1 ?m to 1 ?m when it moves from the high pressure volume to the low pressure volume.

Abstract: A reciprocating engine includes a turbocharging unit that: supplies the intake manifold with air via a coolant; is supplied with gas by the exhaust manifold; and has the turbine supply pressure substantially equal to the compressor discharge pressure. At constant air temperature, the turbocharging unit delivers a substantially constant volume of cooled air when the pressure varies, and the volume is substantially proportional to the turbine outlet section. The turbine pressure is maintained substantially equal to compressor pressure by a EGR bypass between the intake and exhaust manifold. In addition, the volume of air is less than the volume drawn in at the speed so that a flow of hot gases is drawn in again via the bypass above the speed, where the volume drawn in is equal to the volume, and a flow of air is deflected towards the turbine below the speed.

Abstract: In a two-stroke internal combustion engine with a compression-ignition of Diesel type, the exhaust valve or valves (10) are so arranged as to allow flow on at least the major part of their periphery; the piston (3) cooperates with the ceiling of the cylinder head (6) in such manner as to leave, in the vicinity of top dead center, only the required operational clearance between the piston (3) and the part of the ceiling of the cylinder head in which the exhaust valve or valves (10) is or are placed; and a cylindrical recess (14) in which is placed the head (13) of the inlet valve or valves (8) and into which a fuel injector discharges, is arranged in such manner as to constitute practically alone the combustion chamber (7) when the piston (3) is in the vicinity of top dead center.

Abstract: The two-stroke cycle engine employing intake and exhaust valves comprises a combustion and scavenging prechamber having substantially a shape of revolution about an axis and provided with an intake valve seat. Deflecting means or vanes are disposed inside the intake pipe as directly as possible on the upstream side of the seat so as to urge the mass of air into the combustion chamber in the manner of a whirl.

Abstract: The primary zone (1) of the auxiliary combustion chamber has a shape of revolution about an axis (X--X) and is defined by a flame tube (2) which is of cylindrical and/or frustoconical shape, coaxial with said axis (X--X), smooth and devoid of air supply orifices of notable section, and by the chamber inner end (3) which is movable in a direction parallel to said axis (X--X) and cooperates with a fixed seat (13) rigidly connected to the flame tube (2) and separating the primary zone (1) from a cavity (4) so as to constitute, with the chamber inner end (3), throttling means (31) which have a variable passage section and are constituted by a sleeve (10) rigidly connected to a balancing piston (11), which sleeve and piston are coaxial with said axis (X--X), the balancing piston (11) being slidable in a cylindrical bearing surface (12) rigidly connected to the walls of the cavity (4).

Abstract: An internal combustion engine (1), supercharged by a turbocompressor (3), comprises a bypass conduit (11) in which is placed an auxiliary combustion chamber (14). The primary zone (13) of this chamber (14) receives fuel whose flow is determined by regulating means (20). These means (20) vary this flow in the same direction as a parameter which is a characteristic of the load of the engine (1), in particular the temperature of the gases measured in the exhaust of the engine (1) by a sensor (22).

Abstract: An air-to-air radiator is inserted in the circuit of the supercharging compressor of an engine. A turbine which is driven by the exhaust gases of the engine drives the compressor. A regenerator, through which the gases issuing from the turbine pass, is placed in an air circuit connecting the compressor to the motor. The air circuit of the radiator is connected in parallel with the air circuit of the regenerator and a directional valve device is adapted to open one of these air circuits while closing the other and vice versa.

Abstract: The invention uses the supersonic blast occurring when the exhaust is opened in an internal combustion engine having a variable volume combustion chamber.A transfer conduit is provided between the exhaust pipe and the intake pipe, the volume of this conduit being greater than the cubic capacity of the cylinder, as well as a supply channel and a discharge channel, of a smaller section than the conduit, between this latter and the combustive air intake manifold and the burnt gas exhaust manifold.The invention applies principally to supercharged diesel engines with low compression rate.

Abstract: The cylinders of a supercharged two-stroke internal combustion engine have valves, intake and exhaust pipes and a cylinder head constructed for air to be directed from the intake pipe toward the piston along the wall of the cylinders upon opening of the valves and to scavenge the combustion chamber without substantial direct flow of air from the intake pipe to the exhaust pipe along the cylinder head.

Abstract: A supercharged engine is provided with a by-pass pipe through which all the air from the compressor which is not absorbed by the engine flows towards the turbine through an auxiliary combustion chamber. There is provided a system for supplying fuel to the combustion chamber, comprising means for regulating the flow rate of fuel supplied to the auxiliary chamber so as to prevent the supercharging pressure falling below a set value; in which power unit the regulating means comprise sensing means sensitive to the quantity of fuel injected per cycle into the engine so that each value of the said quantity of fuel is made to correspond to a particular set value of supercharging pressure.

Abstract: A diesel engine is supercharged by a compressor driven by a turbine which receives the exhaust gas of the engine. A bypass pipe permits the air delivered by the compressor and not taken by the engine to flow to the turbine. Means for impressing to the air flow in the by-pass a pressure drop which is substantially independent of the rate of flow and increases when the output pressure of the compressor increases comprises an air balanced throttle member in the by-pass and separate control means.

Abstract: A power unit comprises a Diesel engine supercharged by a turbocompressor which has a turbine receiving the engine exhaust gases. A by-pass pipe conveys the air not absorbed by the engine from the compressor to the turbine with a pressure drop which is independent of the flow rate and increases with the compressor outlet pressure. An auxiliary combustion chamber upstream of the turbine receives the air which has travelled through the by-pass. A throttle is disposed in the path of the supercharging air to the engine and is automatically actuated so as to maintain the flow rate of air absorbed by the engine at a value below the flow rate supplied by the compressor under low load conditions.

Abstract: A power unit comprises an internal combustion compression ignited engine having variable-volume combustion chambers and supercharged by a turbocompressor having a turbine which receives the engine exhaust gases. A bypass pipe which is permanently open during operation of the engine returns the air not absorbed by the engine to the turbine with a pressure drop which, if appreciable, is independent of the flow rate and increases with the compressor outlet pressure. The power unit comprises a heat exchanger between the gas flow leaving the turbine and the air flow leaving the compressor. An air cooler is disposed in the path of the air travelling from the heat exchanger to the engine.

Abstract: An auxiliary combustion chamber for use with a supercharged Diesel engine comprises a fuel injection and spraying device adapted to operate with delivery rates which are variable within a broad range. The device has a fuel injection port which opens into the chamber. The size of the port is such that the fuel is mechanically atomized when injected at the maximum rate. Air passage nozzles open into the combustion chamber at a location close to the port and deliver air jets at a speed and at a delivery rate sufficient for it to atomize the fuel effectively at minimum fuel delivery rate.

Abstract: A supercharged Diesel engine comprises a valve whose stem is slidably received in a valve guide, the end of the valve stem co-operating with actuating means located in a casing and lubricated by oil splash. At least one cavity is formed in the inner wall of the valve guide in close proximity to the end of the valve guide closest to the valve disk and communicates permanently with atmospheric pressure or a pressure close to atmospheric pressure. The cavity communicates with atmospheric pressure or with a pressure in the neighborhood of atmospheric pressure or by at least one axial passage formed on the outside of the valve guide and is permanently fed with lubricating oil.

Abstract: For improving idling and low load operation of a low compression supercharged combustion engine provided with a continuously open bypass at low ambient temperature, recycling of exhaust gas is provided. A branch pipe recycles part of the combustion gas delivered by an auxiliary combustion chamber fed by the bypass to the driven gas inlet of an ejector diffuser located between the compressor and the intake manifold of the engine.

Abstract: Diesel engines, equipped with a turbocompressor unit with a combustion chamber upstream of the turbine, comprising a by-pass duct enabling direct and permanent passage between the outlet of the compressor of the turbocompressor unit and said combustion chamber, comprise in addition, for the starting of the turbocompressor unit, a starting device comprising pressure difference generating means. These means are positioned in the by-pass duct in the midst of the air-flow between the compressor and the turbine and arranged to create a flow in the direction of the turbine of the turbocompressor unit. The pressure difference generating means may be constituted by a blower driven by an electric motor, or by an injector supplied with air under pressure and generating a flow by the effect of induction.