An engine control method includes: a first fuel supply step of supplying fuel into the combustion chamber using an injector when a spark plug makes flame in the combustion chamber so that an air-fuel mixture is generated at least around the spark plug, the air-fuel mixture having an air-fuel mass ratio A/F or a gas-fuel mass ratio G/F, in which gas includes air, higher than a stoichiometric air-fuel ratio; after the first fuel supply step, an ignition step of making the flame in the combustion chamber in the compression stroke using the spark plug; and after the ignition step, a second fuel supply step of supplying the fuel into the combustion chamber in the compression stroke using the injector to increase a fuel concentration of the air-fuel mixture in the combustion chamber.

A moment-cancelling, four-stroke engine is disclosed. The engine includes a first cylinder having a first piston and a second cylinder having a second piston, a first crankshaft operably connected to the first piston and a second crankshaft operably connected to the second piston. The first crankshaft rotates in a first direction and the second crankshaft rotates in a second direction that is opposite the first direction to cancel the moments applied to the engine and reduce engine vibration.

A piston construction with an end surface is equipped with a pattern of insulating cavities embedded in an upper end of the piston, between the end surface and interior portions of the piston that are cooled by circulating liquid coolant.

A powertrain engine control method may include: acquiring period information based on tooth information of an engine crank target wheel by using a timer (T); subdividing the period information by a division rate value (R) by using a timer (D) so as to enable the timer (D) to operate R times; carrying out synchronization with the timer (D) and carrying out counting by using a timer (A) from a zero (0) to 720 degrees for a four-stroke engine operation cycle; and correcting, by using a timer (V), an angle counter which is not generated at the time of deceleration of a vehicle.

The aim of the present invention is a method for synchronizing an engine comprising at least one movable piston of a four-stroke internal combustion engine, said method comprising a first step (e1) involving initializing a second memory space, a second step (e2) involving waiting for an edge on a fourth signal (CAM_TOT), a fourth step (e4) involving testing the value of a counter (CPT), an eighth step (e8) involving selecting the theoretical angular positions of the slots of the second signal (CAM_IN) relative to the edges of a first signal (CRK) and of the slots of a third signal (CAM_EX) relative to the edges of the first signal (CRK).

A low emission submersible engine is part of a multipurpose aquatic device, such as an aquatic craft or an electrical generator. A propulsion system having a propeller is coupled to the submersible engine to produce a swimmer propulsion machine and a generator is attached to the engine to produce an electrical generator. The submersible engine receives air from a snorkel that extends up above a water line. The aquatic device has a fuel reservoir which may receive liquid fuel or may receive a fuel cylinder. Floatation chambers keep the aquatic device afloat with the engine submerged. The exhaust assembly and exhaust ports from the engine may also be submerged and the exhaust ports may provide additional thrust. A propulsion system housing integrates the drive shaft and propeller, clutch coupler, exhaust conduits and water flow conduits and is detachably attachable to the engine.

The invention relates to a method (100) for controlling a powertrain system (10) of a vehicle (1) during gear upshifting, said powertrain system comprising: an internal combustion engine system (11) comprising an internal combustion engine (12) configured to output a rotational speed (W1) via an engine output shaft (8); a transmission arrangement (14) having a number of gear stages to obtain a set of gears, the transmission arrangement being operatively connected to the internal combustion engine via a transmission input shaft (64) and further having a transmission output shaft (24) for providing a rotational speed to one or more drive wheels (26) of the vehicle; the method comprising the steps of: operating (110) the engine in a four-stroke operation to provide engine rotational speed output via the engine output shaft; receiving (120) an indication of an intended upshifting from a gear of the set of gears to a higher gear of the sets of gears; reducing (130) the rotational speed of the engine output shaft by adjusting the operation of the engine from the four-stroke operation to a two-stroke braking operation; and, when said engine is in the two-stroke braking operation, performing (140) the intended upshifting from said gear of the set of gears to said higher gear of the sets of gears.

A mechanical engine cylinder system, includes a cylinder, an occupying structure with a cavity, and a crankshaft piston, the cylinder having a dedicated compression space and a dedicated combustion space, the occupying structure having a primary combustion space utilized during an early stage of a power stroke, wherein combustion pressure applied to the crankshaft piston during the power stroke is applied to a smaller surface area of the crankshaft piston during an early stage of the power stroke and to a larger surface area of the crankshaft piston during a later stage of the power stroke, the combustion pressure applied to the occupying structure applies a net-force to the occupying structure in the direction of the crankshaft piston during the early stage of the power stroke, and in the opposite direction of the crankshaft piston during the later stage of the power stroke.

An improved internal combustion engine utilizes at least one orbital-epicycle crankpin eccentrically offset from an orbital shaft, rotationally linked to the main shaft via an orbital-epicyclic gear set, such that the piston and connecting rod, influenced by the force from the thermodynamic process, transfers a straight linear force to the orbital-epicyclic crankpin via a conventional connecting rod and the two-piece flying crank arm to the main shaft. The concept provides a simple way of adjusting or inverting the piston to crank relationship for a different engine application and fuel characteristics with a variety of (dwell duration) ECVC cycle durations to appear at TDC or BDC. Consider that; volume vs pressure/heat are in an opposed proportion!

A camshaft includes, as a cam that opens and closes an exhaust valve and an intake valve, a ball cam whose protrusion amount changes according to rotation of the camshaft, wherein the camshaft has a double structure consisting of an inner shaft and an outer shaft provided in a manner that the inner shaft is helically displaced with respect to the outer shaft around an axis of the camshaft according to a rotation speed of the camshaft, and the ball cam is accommodated movably in a guide groove provided in the inner shaft and protrudes from the outer shaft, and a protrusion amount of the ball cam from the outer shaft changes when the ball cam moves in the guide groove due to the helical displacement of the inner shaft with respect to the outer shaft.