Abstract: A fluid metering pump (1) is disclosed which is operated by a source of pressurised fluid, which in the case of a pump for metering fuel, may be the crankcase (37) of a two stroke, crankcase scavenged, internal combustion engine. The metered quantity of fluid displaced by the pump (1) is a function of the pressure of the pressurised fluid and time that the pressure acts on a pumping means (15) of the pump (1). Attenuation of the pressure may be achieved, especially under idle or high engine speed conditions in the case of an engine, by a throttle (35) placed in a conduit (33) communicating an actuation chamber of the pump (1) with the source of pressurised fluid, such as the crankcase of a two stroke engine.

Abstract: A crankchamber precompression type two-cycle internal combustion engine including at least one cylinder assembly, each cylinder assembly including a stepped cylinder constituted by a minor diameter cylinder portion and a major diameter cylinder portion, a stepped piston received in the stepped cylinder and constituted by a minor diameter piston portion and a major diameter piston portion adapted to be fitted in the minor diameter cylinder portion and the major diameter cylinder portion respectively, a crankchamber connected to the major diameter cylinder portion, a working chamber defined between the minor diameter cylinder portion and the minor diameter piston portion, and a sub-intake chamber defined between the major diameter cylinder portion and the minor diameter piston portion.

Abstract: A crankchamber precompression type two-cycle internal combustion engine including cylinder assemblies of an even number consists of at least one pair of cylinder assemblies having working cycles with 180.degree. phase difference, each cylinder assembly having a stepped cylinder constituted by a minor diameter cylinder portion and a major diameter cylinder portion, a stepped piston received in the stepped cylinder and constituted by a minor diameter piston portion and a major diameter piston portion, the minor diameter and major diameter piston portions being in sliding engagement with the minor diameter and the major diameter cylinder portions of the stepped cylinder respectively to provide an annular space serving as sub-intake chamber in the major diameter portions of the cylinders, the sub-intake chambers being connected to an auxiliary scavenging nozzle oriented toward a combustion chamber of the other associated cylinder.

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: This motor is of the type comprising a case having a cylindrical upper part in which a piston is slidably mounted and a lower part in which a crankshaft connected to the piston is disposed. The case further comprises on one hand, an intake port and an exhaust port which open onto the upper part of the case, the input port being disposed below the exhaust port, and, on the other hand, at least one transfer conduit interconnecting the two parts of the case.The motor comprises a supply circuit for non-carburetted fresh gases which is connected to at least one port of the upper part of the case, the upper edge of this at least one port being disposed below the upper edge of the exhaust port.The motor is applicable in particular to motorcycles.

Abstract: An internal combustion engine operating on a two-stroke cycle and including a piston 1 reciprocable in a cylinder 2 to drive a crank shaft and also to inhale and compress a volume of air is characterized by a second piston 15 working in a separate cylinder 13 co-axial with and opposed to the first cylinder 2, the piston 15 being synchronized with the first piston 1. The second piston 15 acts to introduce a compressed charge of mixture of air and fuel through a non-return valve 30 into a relatively small ignition chamber 34 including a sparking plug 35 and communicating with a combustion chamber 11 in the head of the cylinder 1. The piston 15 draws air/fuel mixture along an inlet passage 20, past a non-return reed valve 21 and into a crank case 22. On the return stroke of the piston 15 the mixture passes through passages 23 in the piston controlled by a non-return valve 24 and also along passages 14 and around the piston.

Abstract: A two-cycle engine (10) has an idle fuel system which admits fuel-air mixture into the transfer passages (22). Heated air is supplied to the idle mixing passage (42) by a serpentine air passage (45), while fuel from the carburetor float bowl (33) is supplied through a needle valve (50). A reed valve (43) admits the idle mixture to the transfer passage (22).

Abstract: A two-stroke cycle gasoline engine having a first scavenging port which is supplied with fuel-air mixture through a mixture passage, and a second scavenging port which is supplied with air, wherein supply of fuel-air mixture through the mixture passage is substantially throttled while supply of air through the second scavenging port is interrupted, so as to perform stratified scavenging, when the engine is operating at low load, while in medium to high load operation the throttling of the mixture passage is released while air is injected through said second scavenging port, so as to generate swirling of mixture charged in the cylinder chamber.

Abstract: A two-cycle internal combustion engine includes a power cylinder, a drive piston being positioned therein. A first transfer duct extends between an auxiliary cylinder, which is supplied with carburetted air and the power cylinder and opens thereinto via a carburetted air inlet port provided on the side wall of the power cylinder or its combustion chamber. A pump crankcase, which is supplied with pure air, is connected to the power cylinder via a second transfer duct which opens thereinto via a scavenging inlet port on the side wall of the power cylinder. An exhaust port is provided on the side wall of the power cylinder. The ports are operatively arranged so that the scavenging port starts to open after the exhaust port and before the carburetted air inlet port.

Abstract: A two-cycle internal combustion engine includes a cylinder, a piston in the cylinder and a crankcase pump. The crankcase pump is divided into a first chamber and a second chamber by a membrane. At least one respective transfer passage connects each of the respective chambers to the cylinder. Inlets are provided for admitting pure air into the first chamber and for admitting carbureted air into the second chamber. Devices are provided for opening that one of the transfer passages communicating between the cylinder and the first chamber first and thereafter for opening the one of the transfer passages communicating between said cylinder and said second chamber during operation of the engine.

Abstract: A single-piston or multi-piston two-stroke internal combustion engine for introducing into the working space or working spaces of the one cylinder or of the several cylinders respectively a pressurized fluid such as a gas, ambient air or a gaseous mixture or a mixture of a gaseous medium and a liquid at approximately an intermediate height of the cylinder working space between top and bottom dead center positions of the piston head surface for separating inflowing fuel-air mixture from the exiting combustion gases and for establishing a layer charge overlying the piston head. The two-stroke engine is provided with an additional inlet port for admitting this additional pressurized fluid into the cylinder working space, the inlet port being in communication with fluid supply means and optionally including an automatically pressure operated or positively actuated control member.

Abstract: A two-cycle free piston engine which is adapted to burn various types of fuel but is particularly adapted to burn gaseous fuel. It introduces the fuel through at least one hole in the side wall of at least one cylinder at a location inwardly of the cylinder air intake and exhaust ports so as to be closed by the power piston at a time or position before the compression pressure in the power cylinder is equal to the injection pressure and also not before the valving system has interrupted the fuel flow. This advantageously keeps the fuel admission controls out of the hottest portion of the cylinder's combustion chamber, gives safer and better mixing of fuel and air and prevents blow back of fuel in the fuel supply line.The fuel admission is preferably started shortly before or after the air intake port is closed, but before the exhaust port is closed and not earlier than is sufficient to prevent the first fuel particles entering the cylinder from escaping through the exhaust port.

Abstract: An internal combustion engine includes an annular or ring-type cylinder and piston therein; exhaust ports from the cylinder lead to an afterburner reactor situated generally medially of the annular cylinder; the exhaust gases are further burned within the afterburner section; to further reduce pollulants during the afterburning process, additional air is pumped into the afterburner section by the ring piston due to its special configuration enabling it to accomplish, for example, triple functions such as: (a) to act as a power transmitting means, (b) to act as a pumping means to supply the engine's combustion chamber with scavenging air and/or an air-fuel mixture, and (c) to act as an air pumping means to supply desired quantities of ambient air into the afterburner section even in timed intervals with a constant predetermined pressure and predetermined quantities in order to thereby maximize the degree of control of the temperature generated in the afterburner and thereby more nearly fully oxidize the unburn