Mazda Motor Corporation

Kyotaro Nishimoto

Daisuke Shimo

Kim Sangkyu

Yoshie Kakuda

Takeshi Yokoo

Keiji Maruyama

Masayuki Tetsuno

Kenko Ujihara

Yuichiro Tsumura

Hiroshi Minamoto

Masahiro Nagoshi

Kota Maekawa

Shinichi Morinaga

A control system for a compression-ignition engine includes a combustion chamber, an injector, an ignition plug, a sensor device, and a controller having a circuitry. The ignition plug forcibly ignites mixture gas to start combustion accompanied by flame propagation of a part of the mixture gas, and again ignites remaining unburnt mixture gas at a timing at which the unburnt mixture gas combusts by self-ignition. The controller is configured to execute an ignition controlling module to output an ignition signal to the ignition plug before a target timing so that the unburnt mixture gas self-ignites at the target timing, an ignition timing estimating module to estimate an actual CI timing indicative of a timing at which the unburnt mixture gas actually self-ignited based on an in-cylinder pressure parameter, and an in-cylinder temperature determining module to determine the in-cylinder temperature at a given crank angle based on the estimated result.

Control system for compression-ignition engine and method of determining in-cylinder temperature

The disclosure provides a diesel engine, which includes an engine body mounted in a vehicle and having a cylinder to be supplied with fuel containing diesel fuel as its main component, a geometric compression ratio &#x3b5; of the cylinder being set within a range of 12:1 to 15:1, and an EGR system for allowing a part of burned gas to exist inside of the engine body cylinder when the engine body is at least in a particular operating state where an engine load and an engine speed are relatively low. The EGR system includes an EGR passage at least partially formed inside the engine body, and having a predetermined or shorter passage, an EGR control valve provided in a course of the EGR passage and for adjusting a flow rate of the burned gas inside the EGR passage, and a controller for controlling an opening of the EGR control valve.

Diesel engine for vehicle

This disclosure provides a method of controlling a diesel engine. The method includes adjusting an EGR ratio according to an engine load so that a cylinder Oconcentration decreases gradually to a predetermined load with an increase in the load of the engine, while the Oconcentration increases gradually above the predetermined load, operating the engine in a premix combustion mode where the fuel injection is terminated before a top dead center of a compression stroke in a low load operating range including the predetermined load where the Oconcentration is lowest and, after that, the fuel ignites and combusts, and operating in a diffusion combustion mode where the fuel injection is executed in parallel to the ignition and combustion of the fuel in an operating range where the load is higher than that of the operating range in the premix combustion mode and the Oconcentration is relatively high.

Method and device for controlling diesel engine

A diesel engine is provided, which includes an engine body to be supplied with fuel containing diesel fuel as its main component, a geometric compression ratio being set to 15:1 or below, a fuel injection valve arranged in the engine body so as to be oriented toward a cylinder of the engine body and for directly injecting the fuel into the cylinder, and a control module for controlling a mode of injecting the fuel into the cylinder through the fuel injection valve. The control module performs a main injection where the fuel is injected to cause a main combustion mainly including a diffusion combustion and performs a plurality of pre-stage injections where the fuel is injected prior to the main injection to cause a pre-stage combustion prior to the main combustion. The control module controls the injection mode of the injections to adjust a heat release rate.

Diesel engine and method of controlling the diesel engine

This disclosure provides a control device for a diesel engine. When the engine is within a particular operating range with a low engine speed and a partial engine load and in a low temperature state where a cylinder temperature at a compression stroke end is lower than a predetermined temperature, a forced induction system sets a forcibly inducting level higher than a predetermined level that is higher than that in a high temperature state where the cylinder temperature is above the predetermined temperature. At least within the particular operating range, an injection control module performs a main injection where a fuel injection starts at or before a top dead center of the compression stroke to cause main combustion mainly including diffusion combustion and performs a pre-stage injection where the fuel injection is performed at least once prior to the main injection to cause pre-stage combustion before the main combustion starts.

Method and device for controlling diesel engine with forced induction system

A diesel engine body is provided with a geometric compression ratio &#x3b5; within a range of 12:1 to 15:1. The engine body has an intake valve for opening and closing an intake passage of a cylinder, an exhaust valve for opening and closing an exhaust passage of the cylinder, and an exhaust gas re-circulation passage communicating with the intake and exhaust passages and for partially re-circulating exhaust to the intake passage. During low engine load and rotation speed conditions, the exhaust valve is opened during an intake stroke, and the intake passage is choked. The exhaust valve is closed before the intake valve in the later stage of the intake stroke. An opening area Sof the exhaust valve is set so that a ratio of Sto an opening area Sof the intake valve meets a relation of:0.01&#xd7;(15&#x2212;&#x3b5;)+0.02&#x2266;&#x2266;0.17.

Growing community of inventors

Hiroshima, Japan

Kyotaro Nishimoto