Denso Corporation

Yusaku Suzuki

Masahiro Yokoi

Hiroaki Fujii

Seiichiro Nishikawa

A control arithmetic unit uses a control storage area to compute a target control amount for combustion of an internal combustion engine according to a user required torque. A monitoring arithmetic unit uses a monitoring storage area to perform computation and to monitor presence or absence of a torque anomaly state in which an estimated torque is deviated from an engine required torque by a predetermined amount or more. The monitoring arithmetic unit computes the estimated torque by using a blow through state amount. The blow through state amount is a quantity of intake air blowing through out of an exhaust port in an intake stroke of the internal combustion engine, a degree to which intake air blows through out of the exhaust port, or an in-cylinder air quantity which is a quantity of air filled into a combustion chamber of the internal combustion engine.

Internal combustion engine control system

A control arithmetic unit uses a control storage area and computes a target control amount for combustion of an internal combustion engine according to a user required torque. A monitoring arithmetic unit uses a monitoring storage area and performs computation and monitoring of presence or absence of a torque anomaly state in which an estimated torque is deviated from an engine required torque by a predetermined amount or more. The monitoring arithmetic unit includes an engine required torque computation unit that computes the engine required torque and an estimated torque computation unit that computes the estimated torque. The engine required torque computation unit computes a reduction in an actual torque, which is caused in conjunction with a retard in ignition timing of the internal combustion engine, as a reserve torque and computes the engine required torque based on the calculated reserve torque and the user required torque.

An engine () is a cylinder injection engine, and includes an injector () that directly injects a fuel into a combustion chamber (), and an ignition plug () that generates an ignition spark in the combustion chamber (). An ECU () performs multiple first injections to each produce an air-fuel mixture of a lean air-fuel ratio in the combustion chamber () before an ignition in one combustion cycle of the engine, and performs a second injection to produce an air-fuel mixture of a rich air-fuel ratio in the combustion chamber () before the ignition and after the first injection. In particular, the ECU implements the multiple first injections in such a manner that the first injection implemented early among the multiple first injections produces an air-fuel mixture leaner than that of the first injection implemented subsequently. The ECU implements the second injection only once immediately before an ignition timing.

Direct injection engine controlling device

The present invention provides a malfunction diagnosing apparatus for an engine which enables selection of a fuel to be supplied to a tank from fuels having different properties. The apparatus includes a determining unit determining whether fuel has been supplied to the tank, a sensor detecting a property of the fuel supplied from the tank to an injection valve, an air-fuel ratio control unit determining an air-fuel ratio correction amount according to a difference between a target air-fuel ratio and an actual air-fuel ratio and according to the property of the fuel sensed by the sensor to correct a fuel injection quantity using the air-fuel ratio correction amount, and a diagnosing unit that definitively diagnoses malfunctions of the determining unit, the sensor, and a fuel system, based on a combination of a determination by the determining unit, detection by the sensor, and the air-fuel ratio correction amount or the difference.

Growing community of inventors

Kariya, Japan

Yusaku Suzuki