Mazda Motor Corporation

Hidetoshi Kudo

Hiroyuki Yamashita

Noriyuki Ota

Hiroyuki Yamamoto

Masashi Marubara

Akira Kageyama

Masayuki Kuroki

Takehiko Yasuoka

A direct fuel injection ignition engine includes combustion chambers with a pent roof type ceiling. Each piston has a top surface with a configuration complementary to the combustion chamber ceiling. A fuel injector is disposed at a peripheral portion of the combustion chamber and injects fuel toward the center portion of the top surface of the piston. A cavity is formed on the top surface of the piston. The cavity has a configuration of an elongated circle with a substantially flat bottom surface. The surrounding side wall of the cavity is substantially upright in relation to the bottom surface. A cavity centerline drawn through the longitudinal axis of the cavity is perpendicular to the injection axis line and offset from the center of the piston toward the injector.

Direct fuel injection ignition engine

A direct injection engine provided with an injector at a peripheral portion of a combustion chamber to inject at least at a latter stage of a compression stroke in at least in a low engine load and low engine speed condition, wherein a distance from the tip end of the injector to an opposite end the combustion chamber is determined greater than a traveling distance of an injected fuel for a time period from a start of a fuel injection at the latter stage of the compression stroke to the ignition timing, wherein; an ignition plug is arranged that an ignition gap is disposed within an injection area of the injector; and, wherein a distance from the tip end of the injector to the ignition gap is determined smaller than said traveling distance of the injected fuel. An ignitability and combustion stability can be improved to thereby improve a fuel consumption efficiency.

Direct fuel injection engine

Growing community of inventors

Hiroshima-ken, Japan

Hidetoshi Kudo