Abstract: A two-cycle internal combustion engine having three, or a multiple of three, cylinders comprises a cylinder head having an intake port and exhaust port opened to a combustion chamber, to which fresh air compressed by a supercharger is introduced via an intake valve. The intake and exhaust valves are operated in response to a crank angle. A one-way valve is provided in the intake port so as to prevent air or gas from flowing back toward the supercharger. The exhaust valve is opened earlier than the intake valve when the speed of the downward movement of the piston is relatively high, so that a part of exhaust gas in the exhaust port flows back to the combustion chamber in the condition. In a heavy load condtion, cross scavenging and air charging effects due to exhaust pulsation can be achieved.

Abstract: An intake device of an engine comprising an intake passage which is common to a first intake valve and a second intake valve. The intake passage is divided into a first straight passage and a second straight passage by a dividing wall which extends toward a point upstream of the intake passage from a position between the first intake valve and the second intake valve. A downwardly projecting separating wall is formed on the upper wall of the intake passage. The separating wall extends from a position upstream of the upstream end of the dividing wall toward a point upstream of the intake passage along the axis of the first straight passage. An intake control valve is arranged between the separating wall and the side wall of the intake passage, which is located on the second straight passage side.

Abstract: A two-cycle internal combustion engine comprises a cylinder head having an intake port and exhaust port opened to a combustion chamber, to which compressed fresh air is introduced via an intake valve. The intake and exhaust valves are operated in response to a crank angle. A pulsation pressure of exhaust gas in the exhaust port is substantially restrained during an idling or light load running condition. The exhaust valve is opened earlier than the intake valve when the speed of the downward movement of the piston is relatively high, such that a part of exhaust gas in the exhaust port flows back to the combustion chamber in that condition. An exhaust gas swirl rotating around a cylinder axis is formed when the exhaust gas flows back and the fresh air is slowly introduced onto the exhaust gas swirl in that condition.

Abstract: An improved induction system for a V type engine that is tuned for substantially all running conditions and which is nevertheless compact in construction. The system includes a pair of air boxes each disposed adjacent one of the cylinder heads of the engine. Each cylinder head has at least two intake passages serving the respective cylinder bores and a first conduit extends from the adjacent air box to one of the intake passages and a second conduit extends from the other of the air boxes to the other intake passage. A throttle valve arrangement is also incorporated so that good performance is achieved under all running conditions.

Abstract: An intake arrangement for an internal combustion engine provided with a intake construction capable of generating a swirl effective for improving combustibility within a combustion chamber during low load operating conditions of the engine, without substantially altering a two intake port system aiming at a high output of the engine.

Abstract: An intake system for a direct fuel injection diesel engine is disclosed which has a cylinder block with a cylinder slidingly receiving a piston. A cylinder head is mounted on the cylinder block, and a fuel injector is adapted to directly inject fuel into a combustion chamber formed between the lower side of the cylinder head and the upper side of the piston, wherein the cylinder head has first and second intake passages which are independent of each other and which are adapted to introduce air into the combustion chamber. The first intake passage is oriented substantially tangentially to the combustion chamber and substantially orthogonally to the axis of the cylinder, and has a helical end portion opening into the combustion chamber to form a swirl of air flowing therethrough. The second intake passage is oriented such that the end portion thereof, adjacent the combustion chamber, is closer to the central axis of the cylinder than the end portion of the first intake passage adjacent the combustion chamber.

Abstract: A diesel engine intake system including a timing valve which is positioned in the intake system in engine starting and warming-up period under a cold engine condition. The timing valve is opened in the final period of the intake stroke so that a strong suction pressure is produced in the combustion chamber before the timing valve is opened. When the timing valve is opened, the intake air is rushed into the combustion chamber at a high speed whereby the intake air is compressed under the inertia of the high speed flow to thereby increase the temperature of the intake air. The timing valve is responsive to the suction pressure in the combustion chamber and opened when the suction pressure becomes stronger than a predetermined level.

Abstract: An improved induction system for a V type engine that is tuned for substantially all running conditions and which is nevertheless compact in construction. The system includes a pair of air boxes each disposed adjacent one of the cylinder heads of the engine. Each cylinder head has at least two intake passages serving the respective cylinder bores and a first conduit extends from the adjacent air box to one of the intake passages and a second conduit extends from the other of the air boxes to the other intake passage. A throttle valve arrangement is also incorporated so that good performance is achieved under all running conditions.

Abstract: An inlet system for an internal combustion engine comprises a plurality of auxiliary inlet passageways which curve and extend outwardly of a plurality of mating main inlet passageways and joining with the main inlet passageways, respectively, at an acute angle at their downstream portions.

Abstract: An embodiment of an induction system for internal combustion engines that permits maximum power output while at the same time insuring good running at low speeds without loss in mid-range torque. Independent intake passages communicate with each chamber of the engine. A throttle valve arrangement is included that includes a first manually operated throttle valve positioned in a common portion of the intake passages, a second manually operated throttle valve that is positioned in the first intake passage between the first throttle valve and the chamber, and a third throttle valve positioned in the second intake passage between the first throttle valve and the chamber. A linkage system interconnects the first and second throttle valves so that the second throttle valve is opened at a predetermined degree of opening of the first throttle valve. The linkage causes the first and second throttle valves to reach their fully opened position simultaneously.

Abstract: A floating tappet guide plate (60) is provided for an internal combustion engine having three tappets (40, 42, 44) per cylinder wherein the guide plate (60) is mounted for movement on the central tappet (40) and is shaped to cooperate with mating surfaces on the remaining tappets to prevent rotation of all three tappets. The tappet guide plate (60) is secured to the circumference of the injector tappet (40) so as to form an integral part thereof and includes opposed squared projections (64) and (66) which extend toward and approximate corresponding flat guide surfaces (50) and (51) of valve tappets (42) and (44), thus permitting the valve tappets to move freely in a vertical direction while simultaneously preventing their rotation and maintaining all three tappets substantially aligned about their central longitudinal axes.

Abstract: A divided chamber internal combustion engine is provided with means to recirculate combustion products from the engine precombustion or auxiliary combustion chamber to the intake prior to or during the main chamber exhaust process. The arrangement limits the exhaust of rich prechamber combustion products to the main chamber and exhaust system and instead recirculates them to the intake for subsequent recombustion and emission control purposes.

Abstract: An internal combustion engine 10 wherein only some compression is carried out in the engine 10 and including a tank 30 of compressed air, a pressure regulator 34, a fuel injector 28, and means 40 and 50 for connecting the foot pedal 38 to the pressure regulator 34 and the fuel injector 28, for controlling air and fuel feed to the combustion chambers 22 in response to throttle demand during high power demand conditions. The engine 10 compresses its own air for cruise conditions but uses stored compressed air (charged from a wayside source) for higher power demand. The engine can use spark or heat ignition, provides full expansion, can be two or four stroke and of the diesel or gasoline type. Compressed air can be generated more efficiently using central station power with a vast savings in the amount of oil consumed. Oxygen enriched (60-80% O.sub.2) compressed air can be used without high temperature problems because of the only partial compression and the high (cooling) expansion ratio and higher rpm.