Abstract: A number of embodiments of two cycle crankcase compression internal combustion engines having at least two cylinders in a common bank in side-by-side relationship. Each embodiment incorporates a main Schnurle type scavenging system that includes a pair of main scavenge passages on opposite sides of the exhaust passage that terminate in main scavenge ports that are disposed in proximity to and on opposite sides of the exhaust port. A transversely extending supplemental scavenge passage is provided for delivering a charge to the combustion chamber to somewhat restrict the scavenging flow so as to prevent fuel from passing out of the exhaust port. Fuel is injected into proximity with this supplemental scavenge passage. This facilitates stratification of the fuel charge. The ports are rotated from normal around the cylinder bore axis in many embodiments to provide a more compact construction.

Abstract: The present invention provides a crankcase compression type two-cycle engine which has a comparatively simple construction, is capable of operating at a low fuel consumption and discharges an exhaust gas having a comparatively low hydrocarbon concentration. The engine comprises a crankcase, a piston, a cylinder joined to the crankcase and provided in its lower part with an exhaust port which is opened and closed by the piston, a cylinder head attached to the upper end of the cylinder, and forming a combustion chamber together with the cylinder and the piston. A poppet scavenging valve is provided in the upper part of the cylinder so as to be opened to the combustion chamber side. A diaphragm actuator operates the poppet scavenging valve using the pressure within the crankcase. The diaphragm actuator is provided with a diaphragm that receives the pressure within the crankcase on one side thereof and receives the pressure of a spring on the other side thereof.

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: A method and device for introducing a carburetted mixture into a first cylinder of an internal combustion engine under pressure, this engine comprising at least one other cylinder with a pump crankcase, further comprising a connecting duct between the crankcase and the first cylinder, with an angular non zero shift between the cycle of each of the cylinders, and at least one of the gas transfer ports of said other cylinder is positioned so that a back-flow occurs therein during a part of the cycle.

Abstract: A cylinder for an internal-combustion two-stroke engine, having multiple intake ports, multiple intake valve ports and multiple exhaust ports. The cylinder enables a two-stroke engine to run on gasoline without premixing it with lubricating oil and, due to its optimal volumetric efficiency and good separation of air-fuel mixture and exhaust gases, provides the possibility to satisfy requirements for high fuel efficiency, high power output and low emissions released into the atmosphere. An engine using this cylinder construction will be lightweight, will not require valve trains and camshaft and can be manufactured with any number of cylinders. Utilizing a slightly different process and slightly different configuration, the present invention will also enable a two-stroke engine to run on diesel fuel and produce significant benefits in comparison to existing two-stroke diesel engines.

Abstract: A device, and method for introducing a carburetted mixture under pressure into a chamber of a first cylinder of a two stroke-internal combustion engine. The device includes a feed valve cooperating with a seat for closing a duct feeding carburetted mixture into the chamber of a first cylinder, a valve returning arrangement and an assistance member comprising a separation element cooperating with one end of a stem of the valve. The assistance member separates a first volume and a second volume within each of which a pressure prevails, with the separation element having a movement and causing displacement of the valve under the action of the pressure difference between the pressure of the first volume and the pressure of the second volume.

Abstract: A two-cycle engine has an air inlet in the crankcase, and a spiral air-fuel passage encircling the cylinder wall rising from the crankcase to an inlet in the cylinder head to effect cooling of the cylinder. A fuel injection device introduces fuel into the transfer passage. A unidirectional valve admits air and fuel into the cylinder head and curved fins impart a swirling action to the air and fuel to effect a fuel and air stratification. An exhaust passage in the cylinder wall has an adjustable throttle to control dirctly the outflow of exhaust gases and indirectly the inflow of fresh fuel-air mixture, whereby the power level of the engine is controlled.

Abstract: A method of preparing a mixture consists in successive performing of: atomization of fuel in a stream of exhaust gases, introduction during suction or an exchange of the load an incombustible fuel-combustion mixture to a separate storage space, compression--in a positive-displacement manner without mixing--of the mixture with the air inflowing to the storage space from the working space of the engine, forcing through of the compressed mixture into the combustion chamber before the top dead center of the piston completing the compression stroke, and in production of a combustible mixture by mixing with air compressed in the combustion chamber.