US 8,620,564 B2 · Abnormality detection apparatus and abnormality detection method for multi-cylinder internal combustion engine

Abstract

An abnormality detection apparatus for a multi-cylinder internal combustion engine changes a fuel injection quantity of a predetermined target cylinder to detect an abnormality of an internal combustion engine based on values of rotational variations relating to the target cylinder detected before and after the change of the fuel injection quantity. The abnormality detection apparatus corrects the values of the rotational variations relating to the target cylinder detected before and after the change of the fuel injection quantity based on at least one of the number of revolutions of the engine and an engine load at a corresponding detection time.

Claims5

Dependent claims

An abnormality detection apparatus for a multi-cylinder internal combustion engine, comprising:

an abnormality detection portion that changes a fuel injection quantity of a predetermined target cylinder in a range in which a misfire does not occur, and detects an abnormal air-fuel ratio shift of the target cylinder, based on rotational variations relating to the target cylinder detected before and after a change of the fuel injection quantity;
and
a correction portion that corrects each values of the rotational variations relating to the target cylinder detected before and after the change of the fuel injection quantity, based on at least one of an engine revolution number and an engine load at a corresponding detection time.

Dependencies are inferred from the claim text.

Facts

Application

13/480,921Filed 25 May 2012

Priority

JP 2011-11813326 May 2011

Published

US 2012/0303248 A129 Nov 2012

Granted

31 Dec 2013

Term ends

Not estimatedThe source records don’t support an estimate.

Classification6 codes

F02D 41/1498
With detection of the mechanical response of the engine: measuring engine roughness
F02D 41/0085
Controlling each cylinder individually: balancing of cylinder outputs, e.g. speed, torque or air-fuel ratio
F02D 41/1495
Details: detection of abnormalities in the air/fuel ratio feedback system
F02D 41/22
Electrical control of supply of combustible mixture or its constituents: safety or indicating devices for abnormal conditions

Abnormality detection apparatus and abnormality detection method for multi-cylinder internal combustion engine

Life of this patent

Abnormality detection apparatus and abnormality detection method for multi-cylinder internal combustion engine

Life of this patent

Abstract

Claims5