Method and system for estimating an air-intake amount of an internal combustion engine, and internal combustion engine

• US 7,769,523 B2
• Filed: 11/29/2007
• Issued: 08/03/2010
• Est. Priority Date: 11/29/2006
• Status: Expired due to Fees

• Current Assignee: Kawasaki Jukogyo Kabushiki Kaisha (Kawasaki Heavy Industries Limited)
• Original Assignee: Kawasaki Jukogyo Kabushiki Kaisha (Kawasaki Heavy Industries Limited)
• Inventors: Sakamoto, Takuya, Suzuki, Ryo, Abe, Takashi, Takenaka, Kenji, Matsushima, Hirohide, Mori, Yoshinobu
• Primary Examiner(s): WOLFE JR, WILLIS RAY
• Application Number:
  US11/998,854
• Publication Number:
  US 20080215229A1
• Time in Patent Office: 978 Days
• Field of Search: 123/295, 123/305, 123/478, 123/480, 123/486, 123491-493, 701101-105, 701/110, 701/113, 701/115
• US Class Current: 701/103
• 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 41/047 Taking into account fuel evaporation or wall wetting; special correction after fuel cut-off F02D41/126
• CPC Class Codes: F02D 41/107 and deceleration
• CPC Class Codes: F02D 41/18 by measuring intake air flow
• CPC Class Codes: F02D 41/2422 Selective use of one or more tables

Abstract

A method of estimating an air-intake amount of an internal combustion engine is provided. The method may comprise detecting a fluid energy amount in an interior of an air-intake passage at first and second points in time while an intake valve is closed from a compression stroke to an exhaust stroke, and calculating a predicted air-intake amount using the values of the fluid energy amounts at the first and second points with reference to an air-intake amount calculation map showing a correlation between the values of the fluid energy amounts at the first and second points and the predicted air-intake amount in the intake stroke, the air-intake amount calculation map being pre-created by finding the values of the fluid energy amounts in the air-intake passage at the first and second points and the air-intake amount, for plural running states of the internal combustion engine.

Claims

1. A method of estimating an air-intake amount of an internal combustion engine, comprising:

detecting a value of a fluid energy amount in an interior of an air-intake passage of the engine at a first point and a value of the fluid energy amount in the interior of the air-intake passage at a second point that is apart in time from the first point in a period during which an intake valve is closed from a compression stroke to an exhaust stroke in one cycle of the internal combustion engine, by a detecting device that is disposed in the air-intake passage of the internal combustion engine to detect the fluid energy amount; and

calculating a predicted air-intake amount in an intake stroke of the engine by a calculation using the values of the fluid energy amounts at the first and second points with reference to an air-intake amount calculation map showing a correlation between the values of the fluid energy amounts at the first and second points and the predicted air-intake amount in the intake stroke in which the fuel is injected, the air-intake amount calculation map being pre-created by finding the values of the fluid energy amounts in the air-intake passage at the first and second points and the air-intake amount, for plural running states of the internal combustion engine.

2. The method according to claim 1, wherein the detecting device is at least one of a pressure sensor, a flow rate sensor, and a fluid speed sensor, and the value of the fluid energy amount is one of a pressure value, a flow rate value, and a fluid speed value.

3. The method according to claim 1, wherein the air-intake amount calculation map is a three-dimensional map.

4. The method according to claim 3, wherein the three-dimensional map has an X-axis indicating the detected value of the fluid energy amount at the first point, a Y-axis perpendicular to the X-axis indicating the value of the fluid energy amount of the second point, and a Z-axis perpendicular to the X-axis and the Y-axis indicating the value of the intake-amount corresponding to the values of the first and second points, which is a value on the air-intake amount calculation map that is obtained by extending in the Z-axis direction an intersection on X and Y coordinates of the first point on the X-axis and of the second point on the Y-axis.

5. An air-intake amount estimating system for an internal combustion engine, comprising:

a detecting device that is disposed in an air-intake passage of the internal combustion engine and is configured to detect a value of a fluid energy amount in an interior of the air-intake passage;

a memory configured to store an air-intake amount calculation map pre-created to show a correlation between the values of the fluid energy amount in the interior of the air-intake passage and a predicted air-intake amount in an intake stroke in which a fuel is injected; and

a processing unit configured to calculate the predicted air-intake amount in the intake stroke, using data relating to a value of the fluid energy amount in the interior of the air-intake passage at a first point and a value of the fluid energy amount in the interior of the air-intake passage at a second point that is apart in time from the first point in a period during which an intake valve is closed from a compression stroke to an exhaust stroke in one cycle of the internal combustion engine, the data being obtained from the detecting device, and with reference to the air-intake amount calculation map stored in the memory.

6. The estimating system according to claim 5, wherein the air-intake amount calculation map is a three-dimensional map in which an X-axis indicates the detected value of the fluid energy amount at the first point, a Y-axis perpendicular to the X-axis indicates the value of the fluid energy amount of the second point, and a Z-axis perpendicular to the X-axis and the Y-axis indicates the value of the predicted intake-amount corresponding to the values of the first and second points, which is a value on the air-intake amount calculation map that is obtained by extending in the Z-axis direction an intersection on X and Y coordinates of the first point on the X-axis and of the second point on the Y-axis.

7. The estimating system according to claim 5, wherein the detecting device is at least one of a pressure sensor, a flow rate sensor, and a fluid speed sensor, and the value of the fluid energy amount is one of a pressure value, a flow rate value, and a fluid speed value.

8. An internal combustion engine comprising:

a fuel injection controller configured to determine an actual fuel injection amount of a fuel injected from a fuel injector into an interior of an air-intake passage of the engine;

wherein the fuel injection controller is configured to estimate a predicted air-intake amount in an intake stroke in which the fuel is injected, and to determine the actual fuel injection amount of the fuel based on the estimated predicted air-intake amount; and

wherein the fuel injection controller is configured to determine the actual fuel injection amount by executing a base fuel injection amount determination control for determining a base fuel injection amount using as parameters an engine speed, a throttle opening degree, and an air-intake pressure of the internal combustion engine before injecting the fuel, and by executing a compensation control of the base fuel injection amount based on the predicted air-intake amount.

9. The internal combustion engine according to claim 8, wherein the compensation control is executed based on an amount of the fuel adhering onto a wall surface of the air-intake passage and an amount of the fuel vaporized from the fuel on the wall surface to be fed to a cylinder.

10. The internal combustion engine according to claim 8, wherein the predicted air-intake amount is determined based on a detected value of a fluid energy amount of air-intake within the air-intake passage.

11. The internal combustion engine according to claim 10,

wherein the value of the fluid energy amount of air-intake is a value of at least one of the air-intake pressure, the air-intake amount, and the air-intake speed.

12. The internal combustion engine according to claim 10,

wherein the predicted air-intake amount is determined based on a value of the engine speed of the internal combustion engine.

13. The internal combustion engine according to claim 10,

wherein the detected value of the fluid energy amount includes values detected at a first point and a second point that is apart in time from the first point in a period during which an intake valve is closed from a compression stroke to an exhaust stroke in one cycle of the internal combustion engine.

14. The internal combustion engine according to claim 13,

wherein one of the first and second points is near a bottom dead center at which the compression stroke of the internal combustion engine starts.

15. The internal combustion engine according to claim 13,

wherein the fuel injection controller has an air-intake amount calculation map pre-created to show a correlation between the air-intake amount of the engine and the values of energy amounts at the first and second points, for plural running states of the engine, and the predicted air-intake amount is calculated with reference to the air-intake amount calculation map by substituting the detected values of the fluid energy amounts at the first and second points.

16. An internal combustion engine comprising:

a fuel injection controller configured to determine an actual fuel injection amount of a fuel injected from a fuel injector into an interior of an air-intake passage of the engine;

wherein the fuel injection controller is configured to estimate a predicted air-intake amount in an intake stroke in which the fuel is injected, and to determine the actual fuel injection amount of the fuel based on the estimated predicted air-intake amount;

wherein the fuel injector includes a first fuel injector provided in the air-intake passage, and a second fuel injector provided in the air-intake passage at a region to be located upstream of the first fuel injector; and

wherein the fuel injection controller is configured to control the first fuel injector and the second fuel injector in such a manner that in a lower output range of the internal combustion engine, the first fuel injector injects the fuel in a large part, while in a higher output range of the internal combustion engine that is higher than the lower output range, the first fuel injector and the second fuel injector inject the fuel of the determined actual fuel injection amount with a predetermined fuel injection amount ratio.

17. The internal combustion engine according to claim 16,

wherein the fuel injection controller is configured to control the first fuel injector and the second fuel injector so that in a transitional running state that is an acceleration state in which the first fuel injector and the second fuel injector inject the fuel, a predetermined fuel injection amount ratio between the first fuel injector and the second fuel injector in a steady running state of the internal combustion engine is compensated such that a rate of a fuel injection amount of the first fuel injector is increased and a rate of a fuel injection amount of the second fuel injector is decreased for a moment.

18. The internal combustion engine according to claim 16,

wherein the fuel injection controller is configured to control the first fuel injector and the second fuel injector so that in a transitional running state that is a deceleration state from a state in which the first fuel injector and the second fuel injector inject the fuel, the predetermined fuel injection amount ratio between the first fuel injector and the second fuel injector in a steady running state of the internal combustion engine is compensated such that a rate of a fuel injection amount of the first fuel injector is decreased and a rate of a fuel injection amount of the second fuel injector is increased for a moment.