摘要:
An engine system and a method of operation are described. The engine may be operating in two-stroke and four-stroke modes while still maintaining a target exhaust air-fuel ratio.
摘要:
A 2-cycle engine has: a piston reciprocably housed in a cylinder bore; an intake opening, an exhaust opening, and a scavenge opening provided in an inner peripheral wall of the cylinder bore and opened/closed by the piston; and a scavenge passage connecting the scavenge opening and a crank chamber. A valve that opens/closes the scavenge passage is provided on the scavenge passage.
摘要:
A discharge valve assembly for a two-stroke internal combustion engine is disclosed, having a cylindrical shutter revolvingly mounted into a housing. A canal is left between the external surface of the shutter and the internal surface of the housing to avoid contact between surfaces and ensure valve seal.
摘要:
An internal combustion engine is operated in accordance with a Miller cycle. The engine includes a piston disposed in the engine cylinder and configured to reciprocate between a top dead center position and a bottom dead center position of the engine cylinder. An air intake valve is coupled to the cylinder. The air intake valve is closed when the piston is about the bottom dead center position in the engine cylinder. An exhaust valve is coupled to the engine cylinder. The exhaust valve is opened for a predetermined time period when the piston is about the bottom dead center position of the engine cylinder after closing the intake valve so as to exhaust a predetermined quantity of fresh charge from the engine cylinder via the exhaust valve.
摘要:
A stratified two-stroke engine having a laminated counterweight is disclosed. The laminated counterweight includes a traditional counterweight portion and a laminate portion. The laminate portion has an approximately circular peripheral shape and at least one notch. In operation, the notch may be used to time the opening and closing of a mixture port or a transfer port.
摘要:
A four-stroke internal combustion engine is equipped with variable valve timing, divided exhaust and a supercharger. The engine is optimized for a low power operation, while charging the cylinder with additional air and dynamically switching the engine into a two-stroke cycle mode satisfies high peak power demand.
摘要:
A variable valve timing mechanism for an internal combustion engine comprising at least one rotary valve (1) having at least two ports terminating as openings (2, 3) in its periphery, a cylinder head (7) having a bore in which the rotary valve (1) rotates, and a window (6) in the bore communicating with a combustion chamber (8). The openings (2, 3) successively align with the window (6) by virtue of the rotation. The mechanism also comprises a drive mechanism (13) driving the rotary valve (1). The at least two ports (2, 3) of the rotary valve (1) are an inlet port and an exhaust port. The drive mechanism (13) varies the angular velocity of the rotary valve (1) at least within a portion of at least one engine cycle while maintaining an average angular velocity over the at least one engine cycle that has a fixed relation to the average angular velocity of crankshaft over the at least one cycle.
摘要:
To provide a two-cycle internal combustion engine including a combustion chamber; a chamber portion adjacent to the combustion chamber; a communication passage between the combustion chamber and the chamber portion; and a control valve, provided in the communication passage, for opening the communication passage nearly at a point of time when a scavenging opening is closed and closing the communication passage at a mid point in the compression stroke, wherein an air-fuel mixture flows from the chamber portion side into the combustion chamber via the communication passage by operating the control valve, which engine is intended to eliminate scattering of fuel in the chamber portion due to splashing of part of the stream of fuel sprayed from a fuel injector. A portion, on the chamber portion side, of the communication passage is taken as a gas passage for communicating the control valve to the chamber portion. A fuel injector for injecting fuel is provided at a mid point in the gas passage via a connection passage in such a manner as to be directed to the inner wall surface of the gas passage while being slightly tilted toward the control valve. A fuel sump recess is provided in a cylinder block at a boundary between the control valve and the gas passage, and fuel is injected in the recess.
摘要:
An internal combustion engine and method for operating the same wherein the combustion chamber volume can be varied depending on throttle position by a member that is inserted into the combustion chamber, and wherein the intake valve is closed before the piston completes its intake stroke so that the expansion stroke is effectively lengthened. In the case of a two-stroke engine, some of the intake gas is expelled before combustion to achieve an effective lengthening of the expansion stroke.
摘要:
A method of and apparatus for starting and accelerating a vehicle through a range of vehicle speeds during which the vehicle internal combustion engine is operated in a plurality of different operating modes is disclosed. Different operating modes are available during normal operation. Under high demand conditions, the engine may be run as a conventional inefficient but effective throttled engine or converted to operation in a fourth mode as a two-stroke cycle engine. The vehicle management system includes a first read only memory for storing a fixed table of engine operating parameters corresponding to various engine conditions, and a random access second storage means for storing a table of engine operating parameters corresponding to various engine conditions with the second table being initially the same as the first table. The system responds to sensed engine conditions to modify the parameters in the second table and controls the vehicle in accordance with the parameters stored in the second table. Both short term modification to accommodate dynamic changes in the sensed engine conditions and long term modification to compensate for relatively slow changes in the engine and the management system are made to the information in the random access memory. The modifications may be on an overall engine basis or an individual cylinder basis.