Mazda Motor Corporation

Noboru Hashimoto

Akinori Yamashita

Fumihiko Saito

Masanori Misumi

Tsugio Fukube

Kenji Hataoka

Hiroyuki Yamamoto

Mitsuo Hitomi

Tatsuya Uesugi

Hidetoshi Nobumoto

Yasuhiro Yuzuriha

Makoto Hotate

Katsumi Okazaki

Yoshikuni Yada

Toru Shiraishi

Koji Onishi

An engine combustion chamber has a protruding wall disposed around a part of each valve seat of either an intake port or an exhaust port. The protruding wall extends in a direction in which a valve for the intake or exhaust port lifts up and down within the combustion chamber and is formed so as to have a jut from a periphery of each valve seat which is set to be less than the larger of a valve lift of the valve of the intake or exhaust port at its top dead center position and a product of a constant and a crank angle from a top dead center of a valve of the other port until the valve of the other port is substantially closed after the top dead center position thereof. A protruding wall gap between inner wall surface of the combustion chamber and an outer periphery of the largest diameter of a valve head of the valve is smaller than the jut, and a valve gap between the outer periphery of the largest diameter of a valve head and an inner periphery of the largest diameter of the combustion chamber is larger than the protruding wall gap.

Combustion chamber of internal combustion engine

An intake system, for use with an internal combustion engine having a plurality of intake valves for each cylinder, includes a plurality of intake ports, opening into the combustion chamber side of the internal combustion engine at different distances from a spark plug of the cylinder. The intake valves are controlled to keep an intake port located at the shortest distance from the spark plug opened only slightly in an early intake cycle stage while opening the other intake ports at their desired timings. The intake port located at the shortest distance from the spark plug is subsequently opened at a desired timing, thereby aspirating a substantial quantity of air through the closest intake port at a later time than through the other intake ports.

Engine control system for multi-valve engine

An intake system for with an internal combustion engine, having a plurality of intake valves for one cylinder, includes a plurality of intake ports, opening into a combustion chamber, with openings which extend toward one side of the internal combustion engine. At least one exhaust port, opening into the combustion chamber, has an opening which extends toward another side of the engine, and is formed in the cylinder head on the other side, which is opposite to the one side of the internal combustion engine. The intake ports are arranged so that the center intake port is inclined at an angle larger than an angle at which other, side intake ports are inclined, so as to direct fuel mixture flows, introduced through the side intake ports, toward an inner surface of the cylinder bore above a top of the piston at a lower dead point.

Intake apparatus for multi-valve engine

A combustion chamber structure including a cylinder head having a bottom surface for defining an upper portion of a combustion chamber, a piston having a top surface for defining a lower portion of the combustion chamber, an intake recess formed in the cylinder head for an intake port of the combustion chamber to define a part the chamber, an exhaust recess formed in the cylinder head for an exhaust port to define a part of the chamber. The intake recess is smaller than the exhaust recess in volume. An extended wall portion is formed at a boundary portion between the intake and exhaust recess in the cylinder head to extend along the intake port and project into the exhaust recess. An ignition plug is arranged in the vicinity of a tip end of the extended wall portion. A compact structure of the combustion chamber can be obtained with an improved combustion property.

An exhaust gas recirculating system for a combustion engine has at least one cylinder communicating with a source of combustible air-fuel mixture through at least one intake port adapted to be selectively closed and opened for effecting the interruption and admission of the supply of the combustible mixture into the combustion chamber, the cylinder also communicating with an exhaust system through first and second exhaust ports both adapted to be selectively opened and closed. The exhaust gas recirculating system includes an intake valve for selectively opening and closing the intake port, first and second exhaust valves each for selectively closing and opening the associated first and second exhaust ports, wherein the first exhaust valve is operable to completely close the associated first exhaust port subsequent to the complete closure of the second exhaust port by the associated second exhaust valve, an exhaust shutter valve for selectively opening and closing a passage extending between the first exhaust port and the exhaust system, and a control unit for controlling the shutter valve according to an engine operating condition to adjust the amount of a portion of the exhaust gases allowed to substantially remain within the cylinder.

Automobile exhaust gas recirculating system

An internal combustion engine is provided with a fuel injection valve in an intake passage communicated with a combustion chamber and a swirl controlling device for controlling a swirling motion to be given to intake air in a circumferential direction of the cylinder forming the combustion chamber. When the engine load is low, the fuel injection valve is controlled to inject fuel by an amount required for one power stroke a predetermined time after the intake valve is opened and during the intake stroke, and the swirl controlling device is controlled to give intake air a swirling motion. A correction device is provided, which, when the engine is cold, controls the fuel injection valve to start fuel injection before the intake valve is opened and also controls the swirl controlling device to suppress production of swirling motion of intake air.

Apparatus for controlling fuel injection and swirl motion of air in

The combustion chamber for an internal combustion engine is formed by a main combustion chamber defined by a recess formed in a part of the lower face of a cylinder head and a squish zone which is a narrow space formed between the top surface of the piston in the top dead center and the substantially flat portion of the lower surface of the cylinder head around the recess. A spark plug is disposed in a position near the squish zone. A fuel injection valve is provided to inject fuel into an intake passage communicated with the combustion chamber by way of an intake valve. The fuel injection valve is controlled, at least when the engine load is low, to inject fuel by an amount required for one power stroke and to terminate fuel injection before the middle of the intake valve opening time at latest so that stratification of air and fuel can be obtained in which rich mixture is accumulated in the lower portion of the combustion chamber and lean mixture in the upper portion of the same.

Fuel injection system for internal combustion engine

A fuel supply control system for an automobile engine comprises a detector for detecting change in engine operating condition, a fuel adjuster for variably controlling the amount of fuel to be supplied to the engine, an A/F ratio setting device for setting the lower or higher A/F ratio of a combustible mixture than the critical A/F ratio to a higher or lower A/F ratio than a critical A/F ratio at which the engine can produce substantially the same or intermediate torque as that produced by the same engine with the supply of such combustible mixture, and a control operable in response to an output from the detector to control the fuel adjuster in such a way that, at the time the engine is desired or required to be switched from one engine operating condition to another, the A/F ratio lower or higher than the critical A/F ratio can be rapidly adjusted to the higher or lower A/F ratio set by the A/F ratio setting device and, thereafter, the A/F ratio can be progressively adjusted to a target or desired value.

Growing community of inventors

Hiroshima, Japan

Noboru Hashimoto