Exhaust gas recirculation device for internal combustion engine

Patent metadata

Field	Value
Publication number	US-10113495-B2
Application number	US-201113697202-A
Country	US
Kind code	B2
Filing date	Sep 12, 2011
Priority date	Sep 21, 2010
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

An exhaust gas recirculation device for an internal combustion engine includes: an opening command signal output unit 52 which outputs an opening command signal in relation to an EGR control valve on the basis of an operating condition of the internal combustion engine; a variation component separation unit 54 which separates the valve opening command signal from the opening command signal output unit 52 into a basic component and a variation component generated so as to be superimposed on the basic component; a variation component determination unit 56 which determines whether the EGR control valve is in a steady state or a transient state on the basis of a magnitude of the variation component separated by the variation component separation unit 54; and an EGR control valve diagnosis device 58 that performs an abnormality diagnosis on the EGR control valve when the variation component determination unit determines that the EGR control valve is in the steady state.

First claim

The invention claimed is:

1. An exhaust gas recirculation (EGR) device for an internal combustion engine, the EGR device comprising:
an exhaust gas recirculation (EGR) control valve provided in an EGR gas passage connecting an exhaust passage and an intake passage in order to control an EGR gas amount; and
an EGR control device that controls the opening and closing of the EGR control valve;
wherein the EGR control device is configured to:
output an opening command signal in relation to the EGR control valve on the basis of an operating condition of the internal combustion engine;
separate the valve opening command signal into a basic component and a variation component generated to be superimposed on the basic component;
determine whether the EGR control valve is in a steady state or a transient state on the basis of a magnitude of the variation component, the EGR control device determining the EGR control valve is in the steady state when the variation component within a threshold is continued for a fixed time;

calculate the valve opening deviation based on the valve opening command signal input into the EGR control valve and an actual measured opening signal relating to the EGR control valve when the EGR control valve is determined to be in the steady state; and
provide the basic component separated from the valve opening command signal to an input of the EGR control valve.

2. The exhaust recirculation device for an internal combustion engine according to claim 1 , wherein the EGR control device further comprises:
a basic component calculation unit configured to calculate the basic component of the valve opening command signal from the valve opening command signal; and
an adder-subtractor configured to separate the variation component from the valve opening command signal by subtracting the calculated basic component from the valve opening command signal.

3. The exhaust gas recirculation device for an internal combustion engine according to claim 2 , wherein the basic component calculation unit further comprises:
a variation component removal dead zone device configured to remove the variation component included in the valve opening command signal;
a correction gain device configured to correct an output signal of the variation component removal dead zone device; and
an integrator configured to integrate an output signal the correction gain device.

4. The exhaust gas recirculation device for an internal combustion engine according to claim 2 , wherein the EGR control device further comprises:
a steady state determination device configured to determine whether or not the variation component generated by subtracting the basic component from the valve opening command signal using the adder-subtractor is within the threshold; and
an on-delay timer configured to switch ON when the variation component is continuously within the threshold for the fixed time;
wherein EGR control device determines the EGR control valve is in the steady state when the on-delay timer switches ON.

Assignees

• Hiroe Takaharu
• Ide Kazunari
• Yamada Tomohide
• Mitsubishi Heavy Ind Ltd

Inventors

• Hiroe Takaharu
• Ide Kazunari
• Yamada Tomohide

Classifications

• F02D41/005

  according to engine operating conditions · CPC title

• F02M26/49

  Detecting, diagnosing or indicating an abnormal function of the EGR system · CPC title

• F02M26/05

  High pressure loops, i.e. wherein recirculated exhaust gas is taken out from the exhaust system upstream of the turbine and reintroduced into the intake system downstream of the compressor · CPC title

• F02D41/0047

  Controlling exhaust gas recirculation [EGR] (temperature control with cooler in recirculation circuit F02M26/33) · CPC title

• Y02T10/47

  Cross-Sectional Technologies · mapped topic