Abstract: The present invention discloses an internal combustion piston engine having a cylinder and a piston, the cylinder having an internal cylindrical bore and an inner wall, the piston being slidable within the cylinder, the piston having a top portion and a skirt portion below the top portion, the skirt having a wide portion with a diameter greater than the diameter of the cylinder bore, the piston being made of a resiliently deformable material and, upon insertion into the cylinder, the piston deforms such that there is no clearance between the wide portion of the piston and the inner wall of the cylinder. The skirt portion of the piston may also have an elliptical cross-sectional profile, the elliptical cross-sectional profile having a long axis longer than the inside diameter of the cylinder and a short axis shorter than the inside diameter of the cylinder.

Abstract: An internal combustion engine has rotary valves associated with movable shutters operable to vary the closing of intake air/fuel port sections to obtain peak volumetric efficiency over the entire range of speed of the engine. The shutters are moved automatically by a control mechanism that is responsive to the RPM of the engine. A foot-operated lever associated with the control mechanism is also used to move the shutters between their open and closed positions.

Abstract: A combination intake air filter for an internal combustion engine and oil collection system for oil in crankcase breather fumes. An enclosed canister having a tubular side wall and two end walls houses a filter element, typically hollow frustum-shaped. A plurality of entrance openings around the periphery of one end wall admit intake air into the canister on one side of the filter element while a central exit opening in the opposite end wall directs the air to the engine after passing through the filter. The entrance openings are sized to create a predetermined pressure drop across the entrance. An inner wall spaced from the sidewall forms and annular space therebetween. An inlet at the top admits breather fumes into the annulus, with a barrier wall between the inner wall and sidewall forces the fumes to travel around the canister through the annulus to an exit connecting the annulus to the canister interior.

Abstract: The invention relates to a partition wall, made up of a multiplicity of segments intended for a multi-compartment furnace as used for firing graphite electrodes, for instance. The invention calls for expansion joints to be incorporated between the segments in a row of segments.

Abstract: A cast cylinder head of light metal incorporates a reinforcement made of a stronger material than the light metal. The reinforcement consists of a relatively narrow elongated steel plate (6) which stretches in a single piece along all the cylinders. The elongated steel plate (6) is provided with transverse arms (8) which stretch out approximately perpendicularly from the steel plate between the valve port apertures (3a, 4a, 5a, 6a) of each cylinder.

Abstract: A control system and control method are described for an engine (12) having a valve controller (42) for controlling exhaust valves (EV.sub.1-4) and intake valves (IV.sub.1-4) of each of the cylinders. Misfire detectors (210-302) provide an indication of ignition misfire in each of the cylinders each engine cycle. In response to a misfire detection, the valve lift of the exhaust valve for that cylinder is set to zero. If the misfire was absent during the cylinder's previous ignition cycle, the intake valve lift is also set to zero. After two successive misfire detections, the intake valve lift is set to a predetermined lift in order to refreshen the air/fuel charge which has been trapped in the cylinder from the previous engine cycles (402-428).

Abstract: A cylindrical cyclone separator connected between an air vent, a suction conduit and an oil sump all of an internal combustion engine. A duct extends spirally within the cyclone separator. Oil and aerosols are separated by an increasing centrifugal force as the oil/aerosol mixtures passes through the duct toward the center of the separator and the separator exhaust ports.

Abstract: Disclosed herein is a four-stroke internal combustion engine including a cylinder, a device for feeding fuel to the cylinder, a sealed crankcase chamber associated with the cylinder, a piston reciprocally movable in the cylinder and relative to the crankcase chamber to effect alternation of the pressure therein in response to piston reciprocation, an oil sump adapted to contain lubricating oil, a conduit system for recirculating oil from the sump to the crankcase chamber and from the crankcase chamber to the sump in response to alternation of the pressure in said crankcase chamber, an oil pump communicable with the oil sump and with the fuel feeding means, and a conduit operably connected to the oil pump and to the crankcase chamber so as to effect delivery of oil from the sump to the fuel feeding device in response to alternation of the pressure in the crankcase chamber.

Abstract: A virtual three-stroke engine (1) with intake and compression strokes approximately one half of the power stroke of approximately 12 to one expansion ratio and with total firing cycle stroke lengths equal to approximately three expansion strokes to minimize engine throttling and frictional losses over the real world drive cycle and provide high torque from a one-to-one drive shaft RPM to engine firing cycle RPM provided by a cam type driver for controlling the piston motions and extracting the power from the piston.

Abstract: In a side-valve internal combustion engine, a combustion chamber in a cylinder head is defined into a substantially triangular pyramid shape having a triangular opened edge. A third angle portion of the opened edge formed by a first slant having a relatively small angle and a second slant having a relatively large angle is offset from an axis of a cylinder bore toward the first slant. Thus, it is possible to a swirl of an air-fuel mixture during an intake stroke to uniformize the air-fuel ratio, thereby providing a reduction in fuel consumption, and producing a swirl of combustion gas during an expansion stroke to eliminate the non-uniformity of combustion, thereby providing an increase in power output and a reduction in amount of unburned components in the exhaust gas.

Abstract: The invention relates to internal combustion engines and provides for the use of a piston cylinder within which a piston slidably reciprocates. A piston rod is pivotally attached at one of its ends to the piston and at its second end to a connector arm which is mounted for pivotal movement below the piston cylinder. A connecting rod is carried by the connector arm to rotate a crankshaft about an axis which is spaced from the pivotal axis of the connector arm. The connecting rod is secured to the connecting arm a distance from the piston rod to transmit the rotational movement to the crankshaft. When the piston moves from a top dead center position to a bottom dead center position, the crankshaft rotates by more than one half of a full revolution, thereby increasing efficiency of the engine.

Abstract: The present invention integrates the combustors and the air intake/exhaust passages in a thermally insulating engine into an assembly to simplify the structure and to space the parts thereof. The space between the subcombustion chamber and the main combustion chamber is reduced by the base installed above the piston head. In addition, a plurality of connection holes are arranged in an oblique radial pattern drilled in the piston head projection creating a vortex within the subcombustion chamber. In the combustion process, the flame expands within the main combustion chamber and mixes with air for combustion. The subcombustion chamber is installed in the center of the cylinder and surrounded by the air intake passage and the exhaust passage. The single-unit structure is made by using a ceramic material for an outer peripheral wall. Additionally, a plurality of the air intakes and exhaust outlets are provided on the piston projection so that respective channels have a wide opening.

Abstract: An adiabatic intake insulator inserted into a portion for connecting a carburetor to a small two-cycle gasoline engine or the like in which the generation of cracks due to stress concentration when bolts are fastened are restrained and the looseness of the fastening member due to the shortage of fastening torque is prevented. The intake insulator comprises: portions for supporting and securing a carburetor; an intake passage through which air-fuel mixture from the carburetor is introduced to the engine; portions for securing the intake insulator to the engine each comprising a through hole for a bolt and a counterbore for accommodating a head of the bolt; and a channel formed on a circumference of a bottom of the counterbore.

Abstract: A conveyor sleeve (6), in particular for conveying air into an internal combustion engine (2), of the kind for reducing resonance caused by air waves in the induction apparatus (1). The wall forming the sleeve (6) provides an alternate succession of star-shaped cross section portions (9) and circular cross section portions (11), said portions (9) being joined to said portions (11) by means of joining wall portions (12).

Abstract: A combustion chamber arrangement for use with internal combustion engines having a piston in an engine block cylinder and a cylinder head secured to the block with a combustion chamber adjacent to the piston surface. One intake valve, one smaller exhaust valve and one centrally located fuel ignition device located in a cylinder head recess are provided for each engine cylinder. The two valves are preferably circular and located on opposite sides of the central ignition device, substantially on a line running through the ignition device. For best results the ratio of the diameter of the intake valve to the diameter of the exhaust valve is at least about 1:3, preferably from about 1.3 to 1.4. Substantially symmetrical squish pads are provided in the cylinder head chamber on adjacent to the row of exhaust valve, ignition device and intake valve.

Abstract: Disclosed herein is an outboard motor comprising a steerable and tiltable propulsion unit including a lower unit including a vertically extending drive shaft housing, a drive shaft extending vertically in the drive shaft housing and located in a plane extending in a fore and aft direction, and a propeller shaft driven by the drive shaft and extending in the fore and aft plane, and a powerhead comprising a four stroke engine including a vertically extending crankshaft located forwardly of the drive shaft and in laterally spaced relation to the fore and aft plane, a cylinder extending horizontally and radially from the crankshaft and at an acute angle to the fore and aft plane, a camshaft extending generally vertically in the fore and aft plane and in vertical alignment with and in driving connection with the drive shaft, and a gear set drivingly connecting the crankshaft and the camshaft for rotatably driving the camshaft at a rotational speed which is one-half of the rotational speed of the crankshaft.

Abstract: The invention relates to an engine manifold having a plurality of branches connecting respective engine ports to ambient air. Each branch of the manifold is connected to pass through an acoustic coupling (10) formed by a chamber (12) of shallow depth having conjugate foci and defined by two closely spaced end plates and acoustically reflective side walls. The branch section (14) of the manifold leading to an engine port (20) is connected to the coupling (10) at one of its conjugate foci. The branch section (18) leading to ambient air being connected to the coupling (12) at a point remote from its conjugate foci, and an acoustic reflector (16) is connected to one of the conjugate foci of the acoustic coupling (10) to reflect sound waves propagating along the branch section (14) leading to the engine port back towards the same engine port (20).

Abstract: A V-type multi-cylinder 4-cycle engine E accommodated in an engine room in an outboard motor includes a pair of left and right banks. A surge tank is disposed in a space defined between both the banks and connected to two left and right combustion chambers through intake ports. A throttle body is connected to a lower portion of the surge tank and also to an intake silencer mounted in a left space of the engine room through an elbow. A subsidiary tank for supplying a fuel to an injector is disposed symmetrically with the intake silencer in a right space of the engine room. The employment of the above-described layout makes it possible to make an intake device move compact in the 4-cycle engine.

Abstract: A variable-compression internal-combustion engine has a two-stage cylinder with a relatively large diameter at a first-stage, supercharge end, which is also a power-takeoff end, than at a second-stage, combustion end of the cylinder. Intake air is drawn into the first-stage, supercharge end of the cylinder by a matching larger-diameter, first-stage, supercharge end of a two-stage piston during a compression stroke of a two-stroke cycle of the two-stage piston. During a power stroke, intake air is directed into and contained under pressure in an air-transfer passage that is positioned circumferentially and externally around an outside periphery of a bottom end of the first-stage cylinder.

Abstract: The swirl control system is provided for varying the swirl of intake air in an internal combustion engine comprising a primary intake air passage for delivering a primary flow of intake air having an initial angular momentum corresponding to a low swirl energy level and a secondary intake air passage connected to the primary passage for directing a secondary air flow at a predetermined flow rate into the primary air flow to form a combined air flow having a combined angular momentum greater than the initial angular momentum of the primary air flow. The secondary air flow enters the primary passage substantially tangential, to the primary air flow so as to substantially avoid destructive interference with the primary air flow thereby minimizing pressure losses in the primary passage. A secondary air flow control valve for controlling the flow of secondary air into the primary passage is operable to vary the combined angular momentum so as to vary the swirl of intake air in the combustion chamber.