Abstract: A two-stroke internal combustion engine having a crankcase provided with a crank chamber, a suction port which opens to the crank chamber, a scavenging passage opening into the crank chamber, and a crankshaft is provided with a flow control surface formed on an inner peripheral wall portion of the crank chamber which is capable of retarding the flow rate of unatomized raw fuel and which extends from the vicinity of the suction port to the vicinity of the scavenging passage. The flow control surface is comprised of a large number of intersecting unit ribs.

Abstract: A two-stroke internal combustion engine having a compressed air assisted fuel injection system. The injection system has an accumulator that uses scavenged air from the crankcase as the compressed air source. The injection system has a valve connected to an exit from the accumulator. The valve is connected to a diaphragm with two diaphragm pressure chambers on opposite sides of the diaphragm. Both diaphragm pressure chambers are connected to pressure in the crankcase; one of the diaphragm pressure chambers by a flow restrictor.

Abstract: A two-cycle internal combustion engine comprising a combustion chamber, an exhaust port and a scavenging port each opening into the combustion chamber. The opening area of each of the exhaust port and the scavenging port is made as small as possible in relation to the engine displacement so as to restrict the revolutions of the engine crank shaft during a rated output operation of the engine. The width in the lateral direction of the opening of the exhaust port corresponds to an angle of 60.degree. as measured from the center of the combustion chamber, and the width in the lateral direction of the opening of the scavenging port corresponds to an angle of 32.degree. as measured from the center of the combustion chamber.

Abstract: A two-cycle internal combustion engine of the fuel injection type, which comprises a cylinder block provided with a combustion chamber and a scavenging passage; a scavenging passage cover constituting a portion of a wall of the scavenging passage; and a fuel injection nozzle mounted on and penetrating through the scavenging passage cover, a distal end portion of the fuel injection nozzle being directed into the combustion chamber so as to inject the fuel directly into the combustion chamber.

Abstract: A two-cycle internal combustion engine provided with at least one fuel injection nozzle, wherein the fuel injection nozzle is provided with a heating element for heating the fuel so as to cause the fuel to undergo a phase change before the fuel is injected from the fuel injection nozzle. A fuel control circuit for controlling the heating element is attached to the engine so that an AC electromotive force generated at a generator portion of an ignition device is input therein and, based on such electromotive force, the heating element is controlled. All of the ignition device, the fuel controlling circuit and the generator portion are formed into a single integrated body which functions as an ignition/fuel controlling device.

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: A four-cycle internal combustion engine wherein the piston connecting rod crankshaft and crankcase chamber are formed so that the crankcase chamber acts as compressor. An induction system supplies atmospheric air to the crankcase chamber and a pressure conduit supplies air from the crankcase chamber to the engine intake valve. A plenum chamber is disposed within this pressure conduit and pressure control is possible by bypassing air form the plenum chamber to the atmospheric air inlet. A throttle valve is positioned downstream of the plenum chamber so as to improve engine braking and charge forming systems are disclosed that permit a compact assembly and good response under all engine running conditions.

Abstract: A number of embodiments of two-cycle engines employing Schnurle-type scavenging. In addition and in some embodiments, a ramble port is also incorporated so as to introduce a tumble charge into the combustion chamber and reduce the likelihood of fresh charge from exiting from the exhaust port. This tumble charge may be utilized to achieve stratification, and the fuel charge may be delivered to the combustion chamber through the tumble port or in proximity to it. Various arrangements are shown for controlling the amount of scavenge flow to improve stratification and fuel vaporization.

Abstract: A fuel injection and ignition control system for a two-cycle crankcase compression engine wherein both fuel injection and ignition timing are controlled by sensed engine running characteristics at a predetermined crankshaft position. The timing of the ignition is controlled by the same parameter at which the fuel injection was controlled, so that the timing of ignition and amount and duration of fuel injection will be optimized for the same engine running condition.

Abstract: A two-cycle internal combustion engine is provided which is capable of preventing the blow-by phenomenon, thereby improving both fuel economy and exhaust purifying performance, and superior in the response of fuel injection volume. In a two-cycle internal combustion engine wherein a chamber is disposed in scavenging passages which provide communication between a crank chamber and a combustion chamber, sealable control valves are disposed in an inlet and an outlet, respectively, of the chamber. A fuel feeding system is provided for the supply of fuel into the chamber. The chamber is brought into communication with one scavenging passage out of a plurality of parallel scavenging passages. The control valve, disposed in the chamber outlet which is on the combustion chamber side and on a scavenging downstream side, is positioned at the bottom part of the scavenging passage communicating with the chamber with respect to the control valve disposed in the chamber inlet which is on the crank chamber side.

Abstract: Air/fuel mixture supply device for a two-stroke internal-combustion engine, of the type with scavenging by compressed air in the casing, comprising at least one cylinder, a piston capable of reciprocating motion in the cylinder, and a scavenging-air compression casing, the cylinder comprising at least one exhaust port, at least one transfer port and a port for introduction of an air/fuel mixture.A rotary closure member (19) driven in synchronism with the rotation of the engine is associated with the port (16) for introduction of the air/fuel mixture into the combustion chamber, this closure member being placed in an air reservoir (14) fed with air under a pressure greater than the pressure in the combustion chamber (10) after opening of the exhaust port (11).

Abstract: A polymer composite reed for a reed valve is provided, wherein the reed has improved mechanical properties as a result of its construction and is highly resistant to chemical and thermal attack. The improved mechanical properties of the reed are primarily due to the reed being reinforced with two plies of fabric having a harness satin weave, which provides the reed with a flexural modulus that is substantially greater in one direction of the reed. The chemical and thermal properties are primarily due to the semicrystalline thermoplastic material from which the reed is formed. In addition, the thermoplastic material enhances the fracture toughness of the reed to improve the durability of the reed. As a result, the reed is highly suitable for applications requiring long life under high speed, cyclic loading, such as that found in two-stroke and four-stroke internal combustion engines for the automobile industry.

Abstract: A two-stroke engine of crankcase scavenged type includes a piston reciprocably mounted in a cylinder, an exhaust port, an inlet port arranged to supply combustion air to the crankcase and a transfer port comprising two or more transfer passages extending between the crankcase and the cylinder. The transfer port is arranged to open before the exhaust port closes whereby, in use, the cylinder is scavenged. Fuel metering means communicates with at least one but not all of the transfer passages and is arranged to supply fuel into the said transfer passage at a rate which is directly determined by the mass flow rate of air through the inlet port. The fuel metering means includes a metering valve connected to actuating means, which is arranged to modulate the valve in response to the mass flow rate of air through the inlet port and fuel supply means arranged to supply pressurised fuel continuously to the metering valve.

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 system for controlling the supply of fuel to a multiple cylinder, two cycle, crankcase compression, internal combustion engine wherein air flow is normally measured by a pressure sensor in the crankcase chamber of only one of the cylinders. When an abnormal condition is sensed, the supply of fuel to the cylinder associated with the pressure sensor is discontinued and in some embodiments, the control of the fuel to the other cylinders is accomplished by means other than pressure sensing.

Abstract: An improved air intake passage arrangement for use on an internal combustion engine is disclosed wherein intake passages are integrated with the crankcase such that an outer wall of the crankcase defines an inner wall of the intake passages. This construction minimizes the size of the engine and promotes heating of the air flowing within the intake passages. In addition, depending upon the location of the fuel supply lines, the air intake structure of the present invention can enhance the vaporization of the fuel sprayed therein.

Abstract: Several embodiments of fuel injection systems for two cycle internal combustion engines wherein fuel is injected into a conduit for delivery into the combustion chamber through a port in the cylinder liner. A nozzle insert is positioned in the conduit and has a restricted opening that forms the discharge through which fuel and gas under pressure are supplied to the combustion chamber for facilitating servicing and replacement.

Abstract: Two embodiments of multiple cylinder two cycle internal combustion engines embodying scavenge manifolds that extend around the cylinder bores and which communicate with the cylinder bores through a plurality of circumferentially spaced scavenge ports. The scavenge ports are arranged so that a charge issuing therefrom is not directed toward the exhaust port and the scavenge ports are staggered so as to permit common scavenge manifolds between adjacent cylinder bores to reduce the length of the engine without adversely effecting its breathing ability.

Abstract: Two embodiments of V-type two cycle crankcase compression internal combustion engines wherein the charge supplied to the crankcase chambers by a primary induction system is supplemented by a secondary induction system that communicates with the crankcase chambers between the primary system and the respective cylinder bank.

Abstract: An internal combustion engine comprising a crankcase, cylinder, a transfer passage communicating between the crankcase and the cylinder and including a first point which is the lowest point in the transfer passage and at which the transfer passage has a first cross-sectional area, and a second point which is spaced from the first point and at which the transfer passage has a second cross-sectional area less than the first cross-sectional area, whereby air flow through the transfer passage establishes a static pressure differential between the first and second points, a sump communicating with the transfer passage at the first point, and a conduit utilizing the static pressure differential for pumping fluid from the sump to the transfer passage.

Abstract: The present invention relates to an internal combustion, reciprocating pin engine with a piston which, on its up-stroke, sucks air or a fuel-air mixture via a flap valve or a similar device into the space beneath its base and, during the down-stroke, sends the then compressed gas via another flap valve or a similar device and a connecting passage to the inlet control ports of said internal combustion, reciprocating piston engine. The pump space of the piston pump which is formed by piston, cylinder liner and annular slide comprises an inlet passage and an outlet passage, equipped with diaphragm valves, respectively.

Abstract: Disclosed herein is a two stroke internal combustion engine comprising a cylinder, a crankcase extending from the cylinder, a piston reciprocal in the cylinder and defining, with the cylinder, a variable volume combustion chamber and defining, with the crankcase, a crankcase chamber having a volume which varies inversely with respect to the volume of the combustion chamber, a transfer passage communicating, subject to piston movement, between the crankcase chamber and the combustion chamber, an air intake passage extending from the crankcase chamber and including therein a throttle valve movable between opened and closed positions to control engine speed, a reed valve located between the air intake passage and the crankcase chamber for controlling communication between the air intake passage and the crankcase chamber, a first fuel injector communicating with the transfer passage, a second fuel injector communicating with the air intake passage between the reed valve and the throttle valve, and a controller fo

Abstract: An arrangement for controlling a two-cycle marine engine having a fuel injection system wherein the firing frequency of the cylinders is reduced under low speed running so as to improve fuel economy and engine performance by improving scavenging while the firing intervals between the cylinders is maintained uniform. The invention is disclosed as being applied to a number of variations of multiple cylinder engines and may be employed with spark ignited or diesel engines since the ignition system of the engine per se is not affected.

Abstract: A two-cycle crankcase compression internal combustion engine for use in an outboard motor that facilitates the use of low quality fuels by providing a carburetor that discharges fuel directly into one of the transfer passages of the engine. The transfer passages and carburetors are disposed so that the carburetors may extend horizontally and permits the use of a plurality of carburetors, one spaced above the others.

Abstract: A fuel supplying device for an internal combustion engine and particularly the engine of an outboard motor operating on the two-stroke principle. The engine is provided with a charge forming device and induction system that is supplied with a liquid fuel having a quality lower than gasoline. A source of pressurized gaseous fuel is also provided for selectively supplying a higher quality fuel to the engine under certain running conditions.

Abstract: A fuel supplying system for a two-cycle crankcase compression internal combustion engine. A first charge forming device supplies a fuel/air charge to the crankcase and a second charge forming device supplies a fuel/air charge to the scavenge passage that connects the crankcase with the combustion chamber. A check valve is positioned in the scavenge passage so as to prevent reverse flow and the discharge of the second charge forming device is related to the check valve so as to improve the fuel delivery.

Abstract: The two-cycle internal combustion engine has a crankcase, a combustion chamber including an exhaust port, a fuel intake port and a pair of air-intake ports located on the opposite sides of the fuel intake port, and a piston movable relative to the combustion chamber between top dead center and bottom dead center positions. The crankcase has separate air and fuel inlets and includes interior portions defining an air crankcase portion which communicates with the crankcase air inlet and with two air transfer passages which communicated with the air intake ports and a separate fuel crankcase portion which communicates with the crankcase fuel inlet and a fuel transfer passage which communicates with the fuel intake port. Air is drawn through the crankcase air inlet into the air crankcase portion and a fuel-air mixture is drawn through the crankcase fuel inlet into the fuel crankcase portion during the upstroke of the piston toward top dead center.

Abstract: A stratified-charge cross-flow scavenged two-stroke cycle spark-ignition engine (1) includes a piston (2) having a raised crown (6) with a baffle (7) and chamfered sides (8, 9) and reciprocal in a cylinder (3) between a combustion chamber (4) and a crankcase (5). Transfer passage structure is disclosed wherein a pair of elongated scavenging air passages (17, 18) extend between the crankcase and combustion chamber on opposite sides of a shorter fuel-air transfer passage (11). A pair of scavenging air inlet ports (20, 21) in the combustion chamber are adjacent the fuel-air inlet port (12) therebetween and substantially distally opposite the exhaust port (16). The scavenging air inlet ports face the baffle at its edges along the chamfered sides of the piston crown.

Abstract: A stratified-charge two-stroke cycle scavenged spark-ignition engine 1 includes a piston (2) reciprocal in a cylinder (3) between a combustion chamber 4 and a crankcase (5). A carburetor (17) is mounted to the crankcase substantially coaxially with the piston to afford narrow engine design. An elongated scavenging air passage (14) extends between the crankcase and the combustion chamber and has a length substantially greater than that of a fuel-air transfer passage (7), and the height of piston (2), to reduce fuel mixture in the scavenging air passage and afford substantially only air at an air inlet port (16), which port is between fuel-air mixture inlet port (8) and exhaust port (13).

Abstract: A 2-stroke engine having a combustion chamber and a scavenge port which is open to the combustion chamber. When the engine is operating under a light load in which a large amount of unburned components, incompletely burned components and oxygen remains in the combustion chamber, fresh air is fed into the combustion chamber from the scavenge port at a low speed so that the fresh air does not disturb the residual gas in the combustion chamber. As a result of this, oxidation of the unburned components and the incompletely burned components continues without interruption during the expansion stroke and the compression stroke and causes self-ignition of the residual gas at the end of the compression stroke. The self-ignited residual gas causes ignition of the fuel injected into the combustion chamber from a fuel injector.

Abstract: A fuel distribution system for an engine (10) having the fuel nozzles (74) located downstream from the air intake reed valves (52) to prevent the operation of the reed valves (52) from effecting the dual flow to the combustion chambers (42) through the transfer tubes (26). A manually operated pump (106) responds to an operator input to add or subtract fuel supplied to a flow divider (98) by a fuel valve (104) to provide a substantially immediate response from the engine to the operator input. A choke (160) receives an input from the engine to allow the mass air flow responsive fuel valve (104) to supply the flow divider (98) with an additional quantity of fuel during a starting operation.

Abstract: The invention contemplates electronically controlled fuel-injection for a single or multiple-cylinder two-cycle internal-combustion engine wherein each cylinder has its own independent crankcase region in which to receive and compress inlet air and fuel, prior to delivery of combustible mixture to the head or combustion end of the cylinder. Fuel is injected directly into each crankcase region during only a portion of the stroke involving induced intake of air therein, i.e., during only a portion of the rise of each piston in its approach to top-center position, and while pressure within the crankcase region is relatively uniform. The time-duration of actual injection is relatively short, to enable identical injections in each cylinder, each such injection being identically timed with relation to position and displacement of its associated piston.

Abstract: The present invention relates to a method for feeding the combustion chamber of a two-stroke engine, according to which the constituents of the combustible mixture are admitted into the combustion chamber via two intake devices at the bottom of the cylinder. Air without fuel is admitted through two ports, symmetrically disposed with respect to the vertical plane containing the axis of the exhaust port, directed towards the wall opposite the exhaust; the petrol-and-air mixture is admitted through at least one port remotest from the exhaust so that the stream of carburetted air is directed towards the cylinder head, the carburetted mixture thus being maintained towards the wall opposite the exhaust by the two streams of air without fuel until the ports are closed. The invention finds particular application in the field of automobile construction.

Abstract: In a crankcase scavenged two-stroke internal combustion engine, a duct and at least one further passage extends between the crankcase chamber and the combustion chamber. There is a fuel/air mixture port leading into the duct and a pure air port leading into the duct or the crankcase chamber. The passage exits into the combustion chamber between the exit into that chamber from the duct and an exhaust port leading out of the combustion chamber. In operation fuel enters the combustion chamber in the air of the fuel/air stream entering the duct and air is additionally pushed into the combustion chamber by the downward movement of the piston through the passage and the duct. The fuel is separated from the exhaust port by a layer of air leading to better fuel consumption and higher oxidation combustion products.

Abstract: Two stroke engines of the crankchamber precompression type are described which include an intake port leading from the intake passage and cyclically opened to the crankchamber by means of the piston. Auxiliary intake passages extend between the intake passage and the scavenging passages and include reed type check valves so that the intake mixture is introduced into the crankchamber as soon as the piston upward movement starts. Additional mixture can also be supplied through the auxiliary passages in the scavenging stroke of the engine operation.

Abstract: A two-cycle internal combustion engine having reed-type intake valving, and specially configured and positioned intake and injector porting, with the porting constructed and arranged to improve various of the operating characteristics of the engine, and particularly adapted to increase the effectiveness of the injection through the injector porting.

Abstract: A two-cycle internal combustion engine having reed-type intake valving, and multiple injector passages and porting constructed and arranged to improve various of the operating characteristics of the engine, and particularly adapted to increase the effectiveness of fuel injection through the injector passages.

Abstract: A two-stroke piston engine and method in which oil-free air is mixed prior to ignition with oil-free fuel, by means of a venturi. The engine is lubricated by utilizing the pressure which the piston exerts in the crankcase to draw an air-oil mix into the crankcase and then to push the air and oil out while filtering the air with a rotary filter, to return the oil to a suitable reservoir, the oil-free air being sent to the venturi. Fuel enrichment, as for cold starting, is caused by placing air pressure on a fuel-containing bowl ahead of the venturi so as to increase the flow of fuel into the venturi, rather than by reducing the amount of air as is done with a conventional choke plate.

Abstract: Crank-chamber precompression type two cycle engines having scavenging ports connected with the crank-chamber through scavenging passages. An air supply passage is connected through a reed type check valve with at least one of the scavenging passages at the upper portion thereof so that air is introduced into the scavenging passage in the ascending stroke of piston movement and discharged into the combustion chamber in the descending stroke of the piston movement to effect scavenging. The air passage is provided with a control valve which is interconnected with the engine throttle valve so that the amount of air supply through the air passage can be controlled in accordance with the load condition of the engine operation.

Abstract: A stepped piston two cycle engine, of the type including at least one set of two cylinders each such cylinder having a working part of smaller diameter and a pumping part of larger diameter, at least the air for each charge required by the working part of each cylinder of the set being pumped along transfer passage means from the pumping part of the other cylinder of the set, has the working part of each cylinder provided with exhaust port means, main inlet ports, and auxiliary inlet port means. The main inlet ports are arranged symetrically about and spaced from a plane which contains a longitudinal axis of the cylinder and which passes through the center of the exhaust port means, and the auxiliary inlet port means is provided in the cylinder wall opposite to the exhaust port means.

Abstract: A two-cycle internal combustion engine having reed-type intake valving, and specially configured and positioned intake and injection porting, with the porting constructed and arranged to improve various of the operating characteristics of the engine.

Abstract: A fuel injection assembly has a fuel injector and an air intake manifold connected to a cylinder of an engine. The air intake manifold has an extension which extends between the injector and the cylinder wall to conduct heat coming from the cylinder wall away from the injector and into the air passing through the manifold.

Abstract: Disclosed herein is an internal combustion engine comprising a crankcase, a cylinder extending from the crankcase and having an inlet port, a piston located in the cylinder, a transfer passage located between the crankcase and the cylinder inlet port, a fuel pump adapted to communicate with a source of fuel for normal operation, a carburetor having an air induction passage communicating with the crankcase and including a venturi, which carburetor also includes a float bowl communicating with the fuel pump and a high speed nozzle communicating between the float bowl and the venturi, a low speed fuel nozzle communicating with the transfer passage adjacent the inlet port, and a fuel line communicating between the float bowl and the low speed nozzle and including therein check valve means preventing flow from the transfer passage to the float bowl and permitting flow from the float bowl to the transfer passage, which fuel line also includes fuel flow metering means.