Patent ID: 7620490
Filing Date: 2009-11-17
Classification: F02D,F02M

Abstract:
1. A fuel injection control device applied to an internal combustion engine having an EGR device for returning, as a part of an intake gas flown into the cylinder, an EGR gas, withdrawn from an exhaust passage, to an intake passage, comprising: an oxygen amount detection device for detecting the amount of oxygen contained in the intake gas; a concentration detection device for detecting the concentration of a specific gas contained in the intake gas or a value representing the concentration; and a smoke tolerable limit value setting device for setting the smoke tolerable limit value as the upper limit of an amount of fuel injection, which can suppress an amount of smoke generated in the engine to a predetermined tolerance range, based on the results detected by the oxygen amount detection device and the concentration detection device, wherein the concentration detection device detects the concentration of oxygen as the concentration of the specific gas, and the smoke tolerable limit value setting device sets the smoke tolerable limit value on the basis of the detected amount of oxygen and concentration of oxygen, and wherein the smoke tolerable limit value setting device determines the smoke tolerable limit value corresponding to a predetermined concentration of oxygen on the basis of the amount of oxygen detected by the oxygen amount detection device, corrects the determined smoke tolerable limit value according to the difference between the concentration of oxygen detected by the concentration detection device and the predetermined concentration of oxygen, and sets the corrected smoke tolerable limit value to the smoke tolerable limit value in the final form.