Control device for internal combustion engine

• US 20050139193A1
• Filed: 12/16/2004
• Published: 06/30/2005
• Est. Priority Date: 12/25/2003
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Kobayashi, Kazuo, Haraguchi, Hiroshi
• Granted Patent: US 7,150,264 B2
• Time in Patent Office: Days
• US Class Current: 123/350
• CPC Class Codes: F02D 13/0215 changing the valve timing only
• CPC Class Codes: F02D 2200/0402 the parameter being determined by using a model of the engine intake or its components
• CPC Class Codes: F02D 2200/0406 Intake manifold pressure
• CPC Class Codes: F02D 2250/18 Control of the engine output torque
• CPC Class Codes: F02D 41/0052 Feedback control of engine parameters, e.g. for control of air/fuel ratio or intake air amount
• CPC Class Codes: F02D 41/144 Sensor in intake manifold
• CPC Class Codes: F02D 41/1441 Plural sensors
• CPC Class Codes: F02D 41/1454 the characteristics being an oxygen content or concentration or the air-fuel ratio
• CPC Class Codes: F02D 41/1458 with determination means using an estimation
• CPC Class Codes: F02D 41/1497 With detection of the mechanical response of the engine
• CPC Class Codes: F02D 41/182 for the control of a fuel injection device
• CPC Class Codes: F02M 26/05 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 Class Codes: F02M 26/10 having means to increase the pressure difference between the exhaust and intake system, e.g. venturis, variable geometry turbines, check valves using pressure pulsations or throttles in the air intake or exhaust system
• CPC Class Codes: F02M 26/23 Layout, e.g. schematics
• CPC Class Codes: F02M 26/33 controlling the temperature of the recirculated gases
• CPC Class Codes: F02M 26/46 for determining the characteristics of gases, e.g. composition
• CPC Class Codes: F02M 26/53 using electric actuators, e.g. solenoids
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

An object of the present invention is to restrain a deterioration of emission even if the actual control condition including the required torque is different from the set control condition. An ECU establishes a control amount of an EGR valve in such a manner that a condition amount, which is a control parameter controlling the EGR valve, is established as a target value. The ECU selects the condition amount as the control parameter among a fresh-air amount, an exhaust oxygen concentration, and an intake oxygen concentration, in which an operation amount of the EGR valve is minimum.

Claims

1. A control device for an internal combustion engine, comprising:

a gas adjusting means for adjusting a gas which makes a mixture gas with an injected fuel;

a gas adjust depending condition amount detecting means for detecting a condition amount indicating an engine condition which varies according to an operation amount of the gas adjusting means; and

a gas adjust controlling means for conducting a gas adjust control in which an operation amount of the gas adjusting means is established in such a manner that the detected condition amount is turned to a target value which is established with respect to a current control condition including a required torque, wherein

the gas adjust depending condition amount detecting means includes a plurality of gas adjust depending condition amount detecting means which detect different kinds of condition amounts, and

the gas adjust controlling means changes the gas adjust control based on one kind of condition amounts into the gas adjust control based on the other kind of condition amounts.

2. The control device for an internal combustion engine according to claim 1, wherein

the gas adjust controlling means executes the gas adjust control based on a condition amount in which a deviation of operation amount of the gas adjusting means is minimum when the control condition is varied in a range including a current control condition.

3. The control device for an internal combustion engine according to claim 2, wherein

the gas adjust controlling means includes a hypothetical target value calculating means which calculates a hypothetical target value of the condition amount in a predetermined range including a current control condition, a hypothetical operation amount deviation calculating means which calculates a deviation of hypothetical operation amount of the gas adjusting means relative to a hypothetical target value, and a selecting means which selects the gas adjusting control based on a condition amount of which deviation of operation amount is minimum.

4. The control device for an internal combustion engine according to claim 3, further comprising:

a predetermined range setting means which sets a predetermined range based on one of the control condition and the engine condition.

5. The control device for an internal combustion engine according to claim 2, wherein

the gas adjust controlling means memorizes a relationship between the control condition and kinds of condition amounts, and executes the gas adjusting control based on the condition amount corresponding to the current control condition.