Mitsubishi Jidosha Kogyo Kabushiki Kaisha

Joji Matsubara

Tadakuni Takeda

Katsunori Ueda

Jun Aoki

Keisuke Nagakura

Shigeo Yamamoto

Kazuyoshi Nakane

Koji Hata

Dai Tanaka

Masayuki Takagaki

In the top face of a piston (), there is formed a cavity () having a bottom surface () which slopes downward toward an exhaust side and which includes a raised part () extending from near the center of the bottom surface to an intake-side wall surface. The cavity guides fuel spray () which has been injected by an injector () and passed by an electrode part () of a spark plug (), to arrive near the electrode part of the spark plug again in the form of an air-fuel mixture ().

Direct-injection spark-ignition internal combustion engine

When, in a coexistence region where stratified combustion by a spray-guide method (SG combustion) and stratified combustion by a wall-guide method (WG combustion) are both practicable, a change from the SG combustion to the WG combustion is carried out, an ECU obtains point b giving a set of a fuel injection timing and an ignition timing capable of achieving the same target torque as a target torque in the SG combustion before the change, by the WG combustion, and changes the fuel injection timing and ignition timing stepwise from point a within an SG region to point b within a WG region, jumping across a misfire region, and then continuously to point c giving an optimal set of a fuel injection timing and an ignition timing corresponding to an MBT.

In-cylinder injection type spark-ignition internal combustion engine

In a direct injection type engine, capable of switching an injection mode between a compression stroke injection mode for injecting fuel mainly during a compression stroke and an intake stroke injection mode for injecting fuel mainly during an intake stroke; a fuel injection starting timing in the intake stroke is corrected to a retard side as the temperature relating to an internal combustion engine, detected as a parameter representing the tendency of fuel to adhere to the inside of the internal combustion engine, becomes lower. If a required fuel injection volume cannot be injected during the intake stroke injection mode in the corrected fuel injection timing, a timing for injecting remaining fuel to satisfy the required fuel injection volume during a compression stroke following the intake stroke in one combustion cycle is determined. The injection of the fuel is controlled according to the corrected fuel injection timing.

Fuel injection timing control system for direct injection type internal combustion engine and method for the same

Growing community of inventors

Seto, Japan

Joji Matsubara