Yamaha Hatsudoki Kabushiki Kaisha

Yu Motoyama

Yoshihiko Moriya

Toshikazu Ozawa

Ryusuke Kato

Junichi Kaku

Ryuichi Ichikawa

Akihiko Ohokubo

Takeru Ibara

Takahiro Suzuki

Michihisa Nakamura

Hidehiro Nishimura

Keiichi Harada

Kousei Maebashi

Miyoshi Ishibashi

Masaki Ohsako

Ryusuke Katoh

A two cycle crankcase compression internal combustion engine wherein a single fuel injector is mounted in the cylinder block and can inject either directly into the combustion chamber or into the induction system through the crankcase chamber through a window in the piston. A control strategy is disclosed wherein the injection occurs primarily into the induction system during either or both of startup and low temperature.

Operating method of two stroke direct injected engine

A direct cylinder injected engine in several different embodiments which are specifically illustrated as two-cycle engines but which can also be used in four-cycle engines. The fuel injector is positioned so as to minimize escape of fuel from the exhaust port in the two-cycle engine applications. In addition, multiple or extended spark plug firing is accomplished under difficult running conditions and wherein fuel vaporization may be incomplete. This will ensure complete combustion. Various control routines and strategies are disclosed that control the number or time of injection depending upon such factors as engine speed, load, speed variation, air fuel ratio variations and pressure variations.

Ignition control system for engine

An exhaust control system for a two-cycle, crankcase compression, direct injection engine wherein an exhaust control valve modifies the effective cross-sectional area of the exhaust system in response to engine speed and operator demand to provide optimum charging and scavenging conditions. The exhaust control system is modified in response to other than normal steady state operating conditions such as during starting, warm up, and during rapid changes in engine speed and/or load and/or operator demand so as to improve performance during these conditions.

Operating control system for 2 cycle direct injection engine

A number of embodiments of exhaust temperature sensors that cooperate with an exhaust control for maintaining optimum engine performance by controlling the exhaust temperature to maintain the desired pulse back effect on the exhaust system.

Engine control and wall temperature sensor

A number of embodiments of two-cycle crankcase compression direct injected internal combustion engines wherein engine speed is controlled under at least some running conditions by cylinder disabling. Exhaust systems including exhaust control valves for precluding the passage of cooler gasses from the disabled cylinders to the operating cylinders through their exhaust ports are illustrated in varying forms and for various types of engines.

Operation control system for direct injection 2 cycle engine

An improved method of operating a direct cylinder-injected engine wherein adequate fuel and scavenging can be achieved at mid and high-mid range by injecting the fuel in two increments. Various control strategies are disclosed, and they all particularly lend themselves for use with two-cycle crankcase compression engines.

Engine control system

A fuel injection and ignition control system for a two-cycle crankcase compression engine wherein both fuel injection and ignition timing are controlled by sensed engine running characteristics at a predetermined crankshaft position. The timing of the ignition is controlled by the same parameter at which the fuel injection was controlled, so that the timing of ignition and amount and duration of fuel injection will be optimized for the same engine running condition.

A number of embodiments of combustion controls for two-cycle internal combustion engines wherein a sensor chamber is provided in which a combustion condition sensor is located. The sensor chamber communicates with the combustion chamber in such a way that only combustion products can flow from the combustion chamber into the sensor chamber. Various valving and control arrangements for achieving this purpose are disclosed.

Air fuel ratio detecting device and system for engines

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.

Fuel injection control

Several embodiments of fuel injected engines wherein stability and running is achieved by maintaining an injection velocity that is greater than the velocity of the charge in the chamber including that component contributed by the squish action in the engine and at least equal to 40 meters per second so as to ensure effective stratification and the existence of a stoichiometric charge at the spark plugs at the time of ignition, even under low load and speed conditions such as idle.

Fuel injection system for engine

Two embodiments of fuel injection systems for two cycle crankcase compression internal combustion engines that employ two fuel injectors. One fuel injector injects into the combustion chamber while another injects into the induction system of the engine. A simplified regulating system is incorporated so that the first injector receives fuel under a higher pressure than the second injector.

Fuel injection system

A fuel injection system for engines for improving performance and fuel economy. The fuel injector controlled along with an exhaust port timing control mechanism so that fuel injected into the engine will not pass out of the exhaust port under most engine running conditions. The invention is disclosed particularly in conjunction with a two cycle crankcase compression engine wherein it has particular utility. The timing of the opening and closing of the exhaust port is changed by means of an exhaust control valve that obstructs the exhaust port under certain running conditions so as to delay its opening and closing.

Injection arrangement for improving fuel consumption

A fuel injection system and method of operating it for a two-stroke crankcase compression internal combustion engine. The engine is provided with a main fuel injector that injects fuel directly into the combustion chamber and an auxiliary fuel injector that injects fuel into the inductions system. A throttle valve controls the flow through the induction system. The system includes a detector for detecting an abnormality in the operation of the main fuel injector and shuts the main fuel injector down when this occurs and increases the amount of fuel supplied by the auxiliary fuel injection. When this abnormal operating condition occurs, the degree of opening of the throttle valve is also reduced.

Operation control device for in-cylinder injection engine

A fuel injection system for a two cycle crankcase compression internal combustion engine including a first injector that supplies fuel directly to the combustion chamber of the engine. An induction system is provided for inducting air into the crankcase chamber of the engine and in a multiple cylinder engine this includes a manifold having a single inlet. A throttle body having a throttle valve controls the flow of air through the inlet and a second fuel injector sprays fuel into the throttle body upstream of the throttle valve and against the throttle valve in certain positions of the throttle valve. In accordance with one disclosed embodiment of the invention, the second fuel injector supplies the fuel requirements for maximum power while the first fuel injector supplies the fuel requirements for low and mid range performance, but does not have adequate capacity to supply all of the fuel for high range performance.

Fuel injection system including supplemental fuel injector

A fuel air injection system for a multiple cylinder engine wherein an air manifold is rigidly affixed to all of the fuel air injectors so as to form a unitary assembly that can be removed from the engine as a unit.

Growing community of inventors

Iwata, Japan

Yu Motoyama