Abstract: A fuel injection system for an engine having a reed type valve in the induction system. The injection system is designed and controlled so that the fuel that is injected is injected substantially entirely before the reed type valve is closed. The time of closing of the reed type valve is determined either by measuring the pressure differential or by recording data indicative of the valve closing in response to various engine running conditions such as speed and/or load.

Abstract: In a two cycle internal combustion engine with uni-directional flow scavenging wherein a piston is disposed in a cylinder so as to be movable between top and bottom dead center end positions, the cylinder has fresh air inlet passages which are so arranged that their bottom walls are disposed below the piston top edge when the piston is in its bottom dead center position so that part of the piston top land is directly exposed to the fresh air flow through the air inlet passages and oil discharge bores extend from the air inlet passages and are in communication with the oil circulating system for the removal of oil wiped off the cylinder wall and collected in the inlet passages.

Abstract: The invention relates to an engine with a constructional design and material composition for optimum thermal conductivity and vibration damping functions. The invention consists in the cylinder section (11) surrounding the combustion chamber being made of a light metal alloy and in the lower part of the cylinder section being connected to a crankcase section (13) with integral lateral walls (21,22) which enclose the cylinder section (11) with an air gap, and the crankcase section is made of a material with higher density than the cylinder section, preferably cast iron.

Abstract: A throttle valve device of a V-type internal combustion engine, comprising a mechanism for operating a throttle valve independently of an acceleration operation by an acceleration pedal. The mechanism includes a DC motor which is drivingly connected to the throttle shaft to control a slip ratio of a road wheel. The DC motor is located below a throttle chamber of the throttle valve device and arranged such that a drive shaft thereof is parallel with and opposite to a throttle shaft on which the throttle valve is mounted, thereby suppressing the width of the throttle valve device in the direction of the throttle shaft.

Abstract: In an engine having free floating reciprocating pistons each with a cam follower which bears on a tri lobed cam, the pistons are arranged in one or more banks of four pistons each of which extends over an angular interval of 90.degree.. Where two banks of four pistons are utilized, the banks may be separated by an angular interval of 30.degree. or 90.degree.. The tri-lobed cam may be sinuously shaped with different profiles according to the desired characteristics of the engine.

Abstract: A process and apparatus for setting the compression ratio of an internal combustion engine by changing the relative distance between the axis of rotation of the engine crankshaft and the engine cylinder head surface delimiting the end of each cylinder in the engine. Relative displacement between the rotational axis of the crankshaft and the cylinder head is effected along a predetermined path that has components both parallel and transverse to the longitudinal axis of each of the engine cylinders. The crankshaft is held with its rotational axis stationary in relation to the engine mountings and the vehicle in which the engine is mounted, and the cylinder head is displaced along the predetermined path together with the cylinder.

Abstract: An exhaust control valve arrangement for a two cycle internal combustion engine for altering the compression ratio to provide optimum running under all conditions. An arrangement is provided or cleaning the exhaust control valve and its surrounding cooperating surfaces of the engine upon shutting off of the engine to preclude the formations of deposits that can cause sticking of the valve element. The valve element is rotated through a number of cycles after the engine is stopped through a wider range than during its normal valving operation for removing deposits. The number of cycles is chosen in response to an engine condition such as length of time of running or amount of lubricant supplied to the engine. Various valve arrangements are disclosed that improve the cleaning operation and permit cleaning even while the engine is running.

Abstract: An intake port of an engine cylinder is directed so as to introduce intake air flow into a combustion chamber in a desired direction. The intake port has a throat portion, extending upstream from a valve port and configured so as to meet the valve port at a given angle, and a transitional throat portion with a small radius of curvature between the throat portion and the valve port.

Abstract: A heat shield formed of composite layers of reflective metallic foil, heat insulating fibers and a non-electrically conducting sheet molding compound which are deformed to the general shape of an operating apparatus. The shield is then clamped about the operating apparatus in spaced relationship between the operating apparatus and a high temperature heat source to prevent heat radiation to the operating apparatus.

Abstract: An internal-combustion engine having an intake system comprises a chamber having an intake connection and individual suction pipes which are connected with a cylinder head and which lead into the individual cylinders. The interior of the chamber is connected to a pollutant reducing system which comprises at least one of the systems, such as a housing venting system, an auxiliary-air feeding system, a fuel vapor catch system and an exhaust gas return system. An intake pipe, which projects into the chamber of the intake system, which has a mouth opening approximately in a plane between two central individual suction pipes, is fastened to the intake connection, and a pipe connection, which connects the systems of the pollutant reducing system, leads into the interior of the chamber.

Abstract: Hydrogen engine with controlled combustion comprises suction means connected to the crankcase reducing or precluding flow of lubricating oil or associated gases into the combustion chamber.

Abstract: A four stroke engine cylinder head (16) has two inlet pipes (19 and 22) which contain alternate acting inlet valves (14 and 15). Fuel/air induction strokes through valve (14) alternate with air only induction strokes through valve (15) giving an eight stroke cycle under half load. When gate valve (23) is moved by a control to the dotted position, this seals the air only inlet and opens port (25) to give fuel/air induction strokes over half load and a four stroke cycle. Air only induction strokes or eight stroke cycles under half load may also be achieved by cutting out some fuel injectors or injection strokes as the load permits.

Abstract: An intake silencer of a vertical-type engine includes two silencing chambers. A first intake silencing chamber is disposed adjacent to the body of the engine; a second intake silencing chamber is located upstream in a flow of intake air from the first intake silencing chamber, and receives the flow of intake air as input thereto. An output of the second intake silencing chamber becomes an input to the first intake silencing chamber. The second intake silencing chamber is disposed at an opposite end of the engine body from the cylinder head of the engine.

Abstract: An intake manifold assembly is disclosed for an internal combustion engine. The intake manifold assembly includes an intake manifold of a predetermined length and includes a plenum having an interior wall surface and a predetermined cross-sectional area in a plane transverse to the length of the plenum. An air inlet is located mid-way of the length of the plenum, and the air inlet is generally circular in cross-section. A plurality of outlet portions, each having an outlet port in air flow communication with the plenum, each of the outlet ports being substantially equally spaced along the length of said plenum. A cross-sectional area of the outlet port of each outlet portion is substantially equal to the cross-sectional flow area of the plenum and of the air inlet portion. A diverter partition extends integrally from the inner wall of the plenum in a direction toward the mid-point of the air inlet to divert incoming air flow and evenly distribute the air flow to each of the respective outlet ports.

Abstract: A valveless four-stroke internal combustion engine employs an intake piston and an exhaust piston that reciprocate within intake and exhaust cylinders disposed adjacent the combustion chamber of the engine. A power piston reciprocates within a cylinder that defines a portion of the combustion chamber. An intake port opens into the intake cylinder, and an exhaust port opens into the exhaust cylinder. Upon reciprocation of the intake and exhaust pistons, the exhaust ports will be covered and uncovered. By coordinating movement of the intake and exhaust pistons with reciprocation of the power piston, a combustible fuel-air mixture will be drawn into the combustion chamber, ignited, and exhausted. The timing and extent of movement of the intake and exhaust pistons can be controlled by a crankshaft or cams.

Abstract: A combustion engine. The engine includes an engine housing; at least one cylinder disposed in the engine housing; and a crank drive including: a crankshaft having a crank; and a piston being axially displaceable within the cylinder. The crank drive further includes a connecting rod which has an upper connecting rod part hinged to the piston; and a lower connecting rod part hinged to the crank. The lower connecting rod part is hinged to the upper connecting rod part. A central joint hinges the upper connecting rod part and the lower connecting rod part to one another, a longitudinal axis of the upper connecting rod part further being defined by a line connecting the central joint with a hinge joint of the upper connecting rod part to the piston.

Abstract: A diesel engine piston, which exhibits high resistance to heat load, has a cooling cavity formed circumferentially around and outwardly of the outer periphery of a reentrant combustion chamber. A cooling liquid inlet passageway through which cooling liquid is supplied is provided in the piston body. The inside diameter of the cooling cavity is smaller adjacent to the top of the piston than adjacent to the bottom of the piston, and the cross-sectional area of the cooling cavity gradually increases from the bottom of the cooling cavity toward the top of the cooling cavity. A funnel wall, which projects downwardly toward the bottom of the piston, serves as the inlet of the cooling liquid inlet passageway. A distributing member, positioned within the cooling cavity directly above the outlet of the cooling liquid inlet passageway, splits the cooling liquid into two streams for passage in opposite directions through two segments of the cooling cavity.

Abstract: A releasable connection for attaching a cover to a molded intake manifold including a series of projections on the cover received into recesses in a flange molded into the manifold. Tapered recesses in the projections and adjacent sloping surfaces in the flange define opposing spaced surfaces, with a key pin inserted between the opposing surfaces to lock the cover to the flange.

Abstract: The invention relates to a portable handheld work apparatus such as a motor-driven chain saw. The apparatus includes an internal combustion engine as a drive motor for a work tool. The engine is mounted in a housing. The engine draws combustion air from the clean compartment of a filter case via an intake channel. The clean compartment is partitioned from a dirt compartment of the filter case by an air filter. The filter case itself is closed by a hood. The cover is configured as a hood of the motor housing and is pivoted about a pivot axis which is held to the motor housing by at least one bearing. In this way, the air-filter case can be cleaned in a simple manner without a tool. When the hood is flipped open, the filter case is freely accessible so that the necessary maintenance of the air filter or cleaning of the filter case is possible.

Abstract: A contra-rotating twin crankshaft system for internal combustion engines. Two crankshafts are arranged in parallel, and are connected together to rotate in opposite directions. At least one piston is spaced from the crankshafts. Connecting rod assemblies extend in a crossed relationship from each crankshaft to two spaced wristpins at the piston. Preferably, one connecting rod assembly is made up of two spaced connecting rods and the other is a single connecting rod which passes between the two spaced connecting rods to form the crossing relationship. If desired, the dual connecting rod assembly may be two spaced single connecting rods or have one connecting rod in the form of a fork, with the single connecting rod passing between the tines of the forked connecting rod.