Mazda Motor Corporation

Toru Kobayashi

Hiromu Sugano

Masahiro Tateishi

Kanae Fuki

Ryohei Karatsu

Jiro Yamasaki

Daisuke Shimo

Kenji Tanimura

Hiroshi Minamoto

Kotaro Takahashi

Takamitsu Miyahigashi

Hirotaka Yamakawa

Sotaro Yoshida

Provided is a start controller for an engine capable of reducing torque of a starter consumed to start the engine. The start controller includes a stop position sensor that detects a position of a piston in each cylinder at an engine stop time, an intake pressure sensor that detects an intake pressure in an intake passage, and a processor that determines whether the position of the piston in each of the cylinders detected by the stop position sensor is within a specified target range after the engine is stopped. In the case where it is determined that the position of the piston in each of the cylinders after the engine stop is out of the target range and the intake pressure detected by the intake pressure sensor is lower than an atmospheric pressure, the engine is started by a motor even when an engine start condition is not satisfied.

Start controller for engine

An intake variable valve timing mechanism (VVT) that collectively changes an intake valve close timing as a close timing of a plurality of intake valves and a control device that controls an engine including a plurality of injectors and the intake VVT are provided. When a specified engine stop condition is satisfied, a fuel cut is performed to stop a fuel supply into a plurality of cylinders by the injector. After the fuel cut, the intake VVT is controlled such that a retarded amount of the intake valve close timing immediately before a stop of a stop-time compression stroke cylinder as a cylinder stopped in a compression stroke from intake bottom dead center is larger than a retarded amount of the intake valve close timing immediately before a stop of a stop-time expansion stroke cylinder as a cylinder stopped in an expansion stroke from the intake bottom dead center.

Stop position controller for engine

A system for controlling a compression ignition engine includes: a speed obtaining section which detects or estimates an engine speed achieved by combustion in an n-th cycle; and an injection amount setting section which sets, in a start period after the start of cranking, a fuel injection amount to be injected by injectors in an (n+1)-th cycle. If the engine speed achieved by the combustion in the n-th cycle falls in the resonance range, the injection amount setting section sets the fuel injection amount for an (n+1)-th cycle to be larger than the fuel injection amount injected when the engine speed is higher than or equal to an upper limit of the resonance range.

Method and device for controlling compression ignition engine

At start of an engine, a fuel injection amount is set to a jump-over injection amount if the engine speed obtained in each cycle is higher than or equal to a determination threshold value, which is set lower than a lower limit of a resonance speed range of powertrain by a predetermined reference value. If the engine speed is lower than the value, the fuel injection amount is set to a step-over injection amount that is smaller than the jump-over injection amount. This setting makes it possible to increase the engine speed such that the engine speed approaches the lower limit of the resonance speed range causing resonance in the powertrain, up to a predetermined range, and then causes the engine speed to jump straight to an engine speed which exceeds the resonance speed range, while in the process of increasing the engine speed by executing the combustion cycles.

Method and device for controlling starting of engine

A system for controlling a compression ignition engine includes: a speed obtaining section which obtains an engine speed; and an injection amount setting section which sets, in a start period after the start of cranking, a fuel injection amount to be injected by injectors in next and subsequent cycles. If an engine speed achieved by combustion in an (n&#x2212;1)-th cycle is higher than or equal to a determination threshold value and lower than a lower limit of the resonance range, the injection amount setting section sets the fuel injection amount for the n-th cycle to a jump-over injection amount, and sets the fuel injection amount for the (n+1)-th cycle to a resonance induction reducing amount, which is smaller than the jump-over injection amount.

A control apparatus for an engine is provided. The control apparatus includes an intake control valve controller for fully closing, when an engine stop request is issued, an intake control valve for adjusting a flow rate of intake air passing through an intake passage of the engine, an engine speed increase controller for increasing an engine speed to reach a target speed after the intake control valve is fully closed by the intake control valve controller, and a fuel injection stopper for stopping a fuel injection after the engine speed is increased by the engine speed increase controller.

Growing community of inventors

Hiroshima, Japan

Toru Kobayashi