Honda Giken Kogyo Kabushiki Kaisha

Kaoru Horie

Hitoshi Takahashi

Kazutoshi Nishizawa

Hiromi Matsuura

Eisuke Kimura

Chihaya Sugimoto

Naoaki Takeda

Hidehito Ikebe

Atsushi Umemoto

Masao Kubodera

Takeshi Iwata

Mitsuharu Imaseki

Susumu Nakajima

Takatoshi Aoki

Kenichiro Kinoshita

Makoto Kishida

Masaki Takayama

Ryuji Matsukado

Michio Shinohara

An EGR control system for a direct injection spark ignition engine operated at a plurality of the combustion modes comprising stratified-charge combustion and premix-charge combustion. The system includes a flow rate control valve equipped at the EGR passage to regulate flow rate of the exhaust gas to be recirculated which is operated when the one combustion mode is determined to be changed to another of a plurality of the combustion modes, thereby ensuring an EGR amount that is neither deficient nor excessive for the combustion mode, while preventing misfire from happening and preventing the degradation of drivability, fuel economy and emission performance from occurring. Alternatively, the system includes an actuator for regulating an opening of a throttle valve or a second EGR control valve installed in a branch passage and a passage switching valve for switching the EGR passage and the branch passage.

EGR control system for internal combustion engine

A gasoline direct-injection engine includes a cavity provided in a top portion of a piston and constituting a portion of a combustion chamber defined between a cylinder head and the top portion of the piston, a fuel injection valve mounted in the cylinder head for injecting gasoline directly into the combustion chamber, and a spark plug also mounted in the cylinder head to face the combustion chamber. In this gasoline direct-injection engine, the fuel injection valve facing a substantially central portion of a ceiling surface of the combustion chamber is mounted in the cylinder head to have an axis substantially parallel to an axis of the piston, and the cavity provided in the top portion of the piston and disposed below the fuel injection valve and the spark plug is defined so that it is deeper in an area corresponding to the spark plug than in an area corresponding to the fuel injection valve. Thus, it is possible to achieve a stable lean laminar burn in wide ranges of rotational speed and load of the engine, thereby providing an improvement in fuel consumption and an enhancement in nature of an exhaust gas.

Gasoline direct-injection engine

An internal combustion engine includes a valve operating device operatively connected to a pair of intake valves and capable of opening and closing one of the intake valves in accordance with the operating condition of the engine and opening and closing the other intake valve in a small lift amount, thereby producing a deflection of the intake air drawn into the combustion chamber, and a fuel injection valve for injecting a fuel toward the pair of intake valve bores that are independently opened and closed by the intake valves, respectively. The timing of the opening and closing of the intake valve that is opened and closed only in the small lift amount is set at a time point such that the lift amount is maximized in the first half of the intake stroke of the piston. This promotes the atomization of the fuel which is being drawn in with the intake air by the opening of the intake valve opened and closed in the small lift amount, and to enhance the combustibility in the combustion chamber.

Internal combustion engine

In an internal combustion engine comprising a valve operating system connected to a pair of intake valves and arranged to open one of the intake valves only in a very small amount such that the one intake valve is brought into its substantially inoperative state, in a suction stroke mainly in a low speed rotation region of the engine, a fuel injection valve capable of injecting fuel toward a pair of intake ports independently corresponding to the intake valves, and a control means for controlling the operation of the fuel injection valve, the control means is arranged to control the fuel injection valve with a fuel injection completion time determined within a suction stroke, when the one intake valve is in the substantially inoperative state. This ensures that when the one intake valves has been brought into its substantially inoperative state, the injection of fuel by the fuel injection valve can be completed in the suction stroke, so that the injected fuel can be sequentially introduced into a combustion chamber in a condition of the other intake valve being open, thereby achieving an axially stratified air charge to provide an improved combustibility.

An internal combustion engine having an assist air supply device for finely dividing injected fuel and an exhaust gas recirculation device for selectively circulating an exhaust gas from an exhaust passage into an air intake passage. In this internal combustion engine, a swirl operation for a lean burn during a low load on the engine and a non-swirl operation for a burn based on a theoretical air-fuel ratio can be selectively switched between such operations. In the non-swirl operation, the supply of an assist air and the recirculation of a large amount of an exhaust gas are carried out. This makes it possible to reduce both specific consumption of fuel and the amount of NO.sub.x in the exhaust gas over the entire operational region of the engine.

A fuel injection type internal combustion engine has a pair of intake ports provided in a cylinder head to connect a pair of intake valve bores facing a combustion chamber with a single intake inlet end. A fuel injection valve is disposed in an orientation frm the intake inlet end toward both the intake valve bores and includes an assist-air supply means for finely atomizing the fuel. A valve operating mechanism is provided for selectively stopping the intake through one of the intake ports in accordance with the operational condition of the engine. A control means is connected to the assist-air supply means for controlling the assist-air supply means to stop the supply of assist air from the assist-air supply means in at least a portion of an operational region in which the intake through one of the intake ports is substantially stopped. This ensures that the impediment of the production of the swirl by the assist air can be avoided by stopping the supply of assist air in a condition in which the intake through one of the intake ports is substantially stopped to produce a swirl in the combustion chamber.

Fuel injection type internal combustion engine

Growing community of inventors

Saitama, Japan

Kaoru Horie