Mazda Motor Corporation

Toru Shiraishi

Shunji Masuda

Hiroyuki Oda

Noriyuki Iwata

Tatsuya Uesugi

Hiroyasu Uchida

Fumihiko Saito

Noboru Hashimoto

A multi-valve internal combustion engine has a plurality of intake valves, and the same number of intake ports as there are intake valves, for each engine cylinder. One of the intake ports forms a helical passage, opening into a center of a combustion chamber of the engine at the location of a spark plug, which is disposed adjacent an intake valve located in the center intake port. In addition to a fuel injector disposed in one of the intake ports, a secondary fuel injector, energized so as to inject fuel when the engine operates at lower loads, is preferably disposed adjacent the intake valve located in the one intake port.

Multi-valve 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 engine intake system including a main intake passage leading through an intake port to a combustion chamber, an auxiliary intake passage branched from the main intake passage and opened to the intake passage, and a control valve provided in the main intake passage and adapted to be opened under a heavy load engine operation and closed under a light load engine operation. A fuel injection valve is provided in the auxiliary intake passage close to the opening of the intake port to the combustion chamber to inject fuel toward the combustion chamber.

Intake system for an internal combustion engine

Growing community of inventors

Hiroshima, Japan

Toru Shiraishi