Abstract: In a method of starting an internal combustion engine, a combustion energy is generated by combusting a fuel that has been injected into a cylinder in an expansion stroke when the internal combustion engine is stopped. In the aforementioned method, the combustion energy generated by combusting the fuel is obtained based on a state of an air/fuel mixture within the cylinder to which the fuel has been injected. Based on the obtained combustion energy, a kinetic energy to be supplied to the internal combustion engine from a primary energy supply source is estimated. A difference between a predetermined target kinetic energy required for starting the internal combustion engine subsequent to the start of combustion and the estimated kinetic energy to be supplied from the primary energy supply source is obtained. The kinetic energy corresponding to the obtained difference is supplied from a secondary energy supply source in the form of a starter motor.

Abstract: To provide a two-cycle combustion engine of a simplified structure with the number of component parts reduced, which is effective to suppress a blow-off of the air/fuel mixture and is excellent in acceleration, the two-cycle combustion engine includes scavenging passages communication between a combustion chamber and a crank chamber, an air/furl mixture passage for introducing an air/fuel mixture from a fuel supply device to the crank chamber, and a branch passage ramified off from the air/fuel mixture passage for supplying a lean air/fuel mixture into the scavenging passages. During an intake stroke, the lean air/fuel mixture from the branch passage is introduced into the scavenging passages and the air/fuel mixture is introduced from the air/fuel mixture passage into the crank chamber. During a scavenging stroke, the lean air/fuel mixture is supplied from the scavenging passages into the combustion chamber prior to introduction of the air/fuel mixture.

Abstract: A four-stroke engine includes a piston cylinder, and a piston located in the cylinder and movable within the cylinder. The engine includes a crankcase attached to the cylinder, the piston providing a separation boundary of a combustion portion of the cylinder from the crank case, and a crank member located within the crankcase and operatively connected to the piston. The engine including components for operating the engine in a four-stroke sequence, and components for introducing a fuel mixture into the combustion portion of the cylinder, the fuel mixture having an ability to lubricate. The engine including a construction and/or configuration for promoting passage of a portion of the mixture from the combustion portion of the cylinder to the crankcase in a sufficient amount to provide lubrication within the crankcase without reservoir lubricant in the crankcase.

Abstract: An internal combustion engine and a transmission are supported by a saddle-ride type vehicle body having a front wheel in a front portion thereof. An oil cooler is installed without interference with other parts such as, for example, an exhaust pipe and the front wheel. Further, the distance between a water pump and the oil cooler is made shorter to shorten the length of a cooling water pipe. The power unit includes a crank shaft, an output shaft disposed in a rear portion of the power unit to output torque produced by the crank shaft to the exterior through a transmission, a water pump is adapted to be rotated with the torque transferred thereto from the crank shaft, and an oil cooler mounted on a rear surface of the power unit in a vehicle advancing direction below the output shaft and at a position lower than the crank shaft.

Abstract: Method and system embody a valve timing strategy to control the autoignition timing of a four stroke internal combustion engine (10) operated in an HCCI mode at different engine operating conditions such as different engine speed and torque. A particular valve timing strategy varies lift timing of the intake valve (20) relative to the exhaust valve (28), or vice versa, and relative to top dead center in response to a change in engine torque, for example, to vary amount of trapped residual burned gas in the combustion chamber (12) flowing to an intake or exhaust port (16,18) and back to the combustion chamber during which the residual gas is cooled. Control of the flow of residual gas between the combustion chamber and intake or exhaust port and thus its temperature by the valve timing strategy, in turn, is used to control the temperature of the fresh air/residual gas/fuel mixture in the combustion chamber (12) and thus autoignition timing in response to a change in engine torque.

Abstract: The invention relates to an oil collecting arrangement for an internal-combustion engine having an oil collecting housing (2) arranged below a crankcase, which oil collecting housing (2) has at least two sections of different space depths, in a deeper space section (4), an oil scavenging line (8) being provided by means of which the lubricating oil is delivered to the consuming devices by way of a pump. It is suggested that, in the oil collecting housing (2), a separate insertion part (18) is fastened which, on the one hand, has an oil barrier (22, 28) aligned transversely to the longitudinal dimension of the oil collecting housing (4) (2), which oil barrier (22, 28) prevents a flowing back of the lubricating oil from the deeper space section (4) into the crank space and/or into the flatter space section (12) in the inclined position of the internal-combustion engine, and which, on the other hand, has oil return ducts (34, 38, 40) for the lubricating oil flowing back from the cylinder head.

Abstract: Internal combustion (I.C.) systems and methods provided herein substantially eliminate incomplete combustion, unburned hydrocarbon emission, and hydrocarbon, CO, NOx, and SOx emissions. A method of one embodiment includes the steps of providing a fuel stream containing acetylene, providing an I.C. engine, and introducing the fuel stream to the engine's intake port. A method of another embodiment includes the steps of providing a fuel source selected from the group consisting of acetylene and hydrogen, providing an I.C. engine, and introducing the fuel source to the engine's intake port. Still another embodiment's method includes the steps of providing a fuel stream that doesn't include gasoline, diesel fuel, or an alcohol selected from the group consisting of C1–C20 alcohols, providing an I.C. engine, and introducing the fuel stream to the engine's intake port. In an embodiment, an I.C. system is provided, including an I.C. engine and a fuel stream containing acetylene.

Abstract: To provide a two-cycle combustion engine, in which the blow-off of the air-fuel mixture used as the scavenging gas is avoided and the combustion efficiency of the air-fuel mixture can be increased, the two-cycle combustion engine includes first and second scavenge passages (11, 12) for supplying the air-fuel mixture (M) from a crank chamber (2a) into the combustion chamber (1a) of the combustion engine. Each of the first and second scavenge passages (11, 12) has a lower end portion thereof extended to assume the position where it confronts an outer end face of a bearing (81) for the crankshaft (8), so that the air-fuel mixture (M) within the crank chamber (2a) can be introduced into the first and second scavenge passages (11, 12) through the bearing (81) and be then supplied into the combustion chamber (1a) through the first and second scavenge passages (11, 12).

Abstract: The invention provides a multi-cylinder engine wherein, even where it is structured such that a cam chain case is provided on a side portion of the engine, a working fluid supply path can be simplified and the weight and size of a cylinder head reduced. According to the invention, a multi-cylinder engine is provided wherein at least one of a plurality of engine valves of a cylinder head can be cut off from its corresponding combustion chambers such that a first intake valve, a second intake valve, a first exhaust valve, and a second exhaust valve are positioned on the opposite side to a cam chain case.

Abstract: An outboard motor has an engine and a mounting case disposed below and connected to the engine. The mounting case has a depression opening upward. The opening is covered by a cover to form a coolant chamber. An exhaust passage passes through the coolant chamber and communicates with an exhaust expansion chamber formed by an extension case to be positioned below the mounting case. The coolant chamber is covered by the cover so that a small mating surface is formed with the coolant chamber independently of an engine mating surface of the mounting case. This simplifies the structure of the mounting case.

Abstract: The intake system includes an intake path forming section having a downstream end in communication with an intake port included in each of cylinder heads of a pair of banks of an engine main body. The intake path connects to the common air chamber with an upstream end of the intake path being open in the air chamber. A fuel injection valve for injecting fuel toward the upstream end opening portion of each intake path is disposed in the air chamber. A path forming member constituting at least part of an intake path forming section by forming an upstream end of an intake path is connected to a first wall portion of an air chamber. A fuel injection valve is mounted from the outside in a second wall portion of the air chamber opposing the first wall portion with a leading end portion facing an inside of the air chamber.

Abstract: In a system for controlling an internal combustion engine having a plurality of cylinders and connected to the automatic transmission and mounted on a vehicle and the operation of the engine is switched between full-cylinder operation during which all of the cylinders are operative and cutoff-cylinder operation during which some of the cylinders are non-operative, based on at least the load of the engine, a gradient of road on which the vehicle runs is estimated and the cutoff-cylinder operation is prohibited when the estimated gradient is equal to or greater than a threshold value. With this, it becomes possible to generate sufficient deceleration, when the vehicle runs a downhill during cutoff-cylinder operation, while ensuring to prevent the operator to feel excessive acceleration.

Abstract: An improvement to a diesel engine cylinder head disclosed in U.S. Pat. No. 4,860,700, wherein the improvement comprises any of: a by-pass opening formed in partition walls thereof; a spine density of less than about five spines per square inch; spacing an inner chamber wall surface thereof with respect to an inner fire-face wall surface thereof between about 0.75 inches and 0.25 inches; coolant by-pass ports thereof having a cross-section of between about 0.1875 inches and 0.0625 inches; and a radial rib thereof extending complete and free of any rib opening.

Abstract: Various systems and methods are disclosed for carrying out combustion in a fuel-cut operation in some or all of the engine cylinders of a vehicle. Further, various subsystems are considered, such as fuel vapor purging, air-fuel ratio control, engine torque control, catalyst design, and exhaust system design.

Abstract: To provide a universally usable free-piston device with electric linear drive, comprising at least one piston receptacle with at least one piston device arranged for linear displacement in the piston receptacle, the piston device comprising a traveller device, and a stator device being arranged on the piston receptacle, and the at least one piston device being drivable under the action of a medium which expands in an expansion space, it is proposed that the piston stroke be variably adjustable via the linear drive such that the dead centers of the displacement of the piston device are definable.

Abstract: A cooling structure of a cylinder block includes a water jacket portion which is provided so as to surround an entire outer periphery of a bore wall; and a water jacket spacer which is inserted in the water jacket portion. A foreign matter collecting mechanism which collects foreign matter is provided in a bottom portion of the water jacket portion.

Abstract: An engine-driven work machine enables the work machine and its electrical components to be properly cooled. An engine-driven work machine comprises an engine, a work machine driven by an engine, and electrical components belonging to the work machine, and supplies an output for work while being driven by the engine; the engine-driven work machine has an open machine accommodating section, which is provided in a main body of the work machine and accommodates an engine and a work machine driven by the engine, and a control box for accommodating part of the engine, electrical components of the work machine, and a fuel tank; the control box is provided above the machine accommodating section, and has a ventilation path that connects to a fan fitted to the engine, the electrical components and the fuel tank being arranged along the ventilation path.

Abstract: An air cleaner unit of the present invention includes a removable cleaner case having defined therein an outflow port, located below the filter element, for discharging an air, introduced into the cleaner case, towards the combustion engine and including a case body opening downwardly and a bottom plate closing the opening of the case body, and a filter element replaceably accommodated within the cleaner case for substantially purifying the air introduced into the cleaner case through an air intake port. A pedestal is carried by the combustion engine and has an outer peripheral surface, which is substantially in flush with an outer peripheral surface of the filter element within the cleaner case. This filter element within the cleaner case is removably mounted on the pedestal. The bottom plate has a mounting hole defined therein and encircling the outer peripheral surface of the pedestal.

Abstract: An engine system with a thermal storage device is capable of efficiently supplying heat from a thermal storage device to an internal combustion engine. The engine system equipped with the thermal storage tank supplies the hot water stored in the thermal storage tank to a cylinder head of the internal combustion engine before the starting thereof. At this time, an electronic control unit sets a target value of the temperature of the internal combustion engine at the start of the hot water supply in such a manner that the lower the temperature of the internal combustion engine, the lower the target value becomes. As a result, a variation in combustion states between cylinders can be suppressed at the starting of the internal combustion engine.

Abstract: A cylinder block structure with a small number of ribs is provided which can favorably prevent the deformation of a crankshaft bearing portion. In a cylinder block having bolt holes formed on the upper surface for connecting a cylinder head with bolts, arcshaped coupling surfaces formed on the rear end surface for mounting a housing, such as a transmission housing, and a crankshaft bearing portion formed in the central part between the lower ends of the coupling surfaces, the upper parts of the coupling surfaces 5 are joined into an arch-shape by an arch-shaped rib, the lower ends of right and left bosses are extended and connected to the lower parts of the arch-shaped rib, and right and left main radial ribs extend from the outside of the lower end of the bolt hole boss to the center of the crankshaft bearing portion.