Search

BR-102025013089-A2 - CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE

BR102025013089A2BR 102025013089 A2BR102025013089 A2BR 102025013089A2BR-102025013089-A2

Abstract

The present invention relates to a control apparatus (100) for an internal combustion engine (1), which includes: an injection mode switching unit (25) configured to switch an injection mode for injecting fuel into the combustion chamber (5) of the engine (1) to one of a plurality of injection modes, according to the operating state of the engine (1); a correction coefficient calculation unit (28) configured to calculate a correction coefficient (K) to increase a reference injection quantity (Q0) of fuel, calculated according to the operating state of the engine (1) for a predetermined period from the moment of starting the engine (1); and a limit value calculation unit (29) configured to calculate a limit value (GaL) of the intake quantity of the engine (1) for a predetermined period. The correction coefficient calculation unit (28) calculates the correction coefficient (K) to gradually decrease as the engine combustion cycle (1) progresses, based on a predetermined characteristic for each of the plurality of injection modes. The limit value calculation unit (29) calculates the limit value (GaL) to gradually increase as the correction coefficient (K) decreases.

Inventors

  • Taijiro Kawamura
  • Tadaaki Tsuji
  • Kazushi Kikuchi

Assignees

  • HONDA MOTOR CO., LTD

Dates

Publication Date
20260310
Application Date
20250625
Priority Date
20240710

Claims (6)

  1. 1. Control apparatus (100) for an internal combustion engine (1), characterized in that it comprises: an injection mode switching unit (25) configured to switch an injection mode for injecting fuel into a combustion chamber (5) of the engine (1) to one of a plurality of injection modes according to an operating state of the engine (1); a correction coefficient calculation unit (28) configured to calculate a correction coefficient (K) to increase a reference injection quantity (Q0) of fuel calculated according to the operating state of the engine (1) for a pre-determined period from a start time of an engine activation (1); a limit value calculation unit (29) configured to calculate a limit value (GaL) of an engine intake air quantity (1) for the predetermined period, wherein the correction coefficient calculation unit (28) calculates the correction coefficient (K) to gradually decrease as an engine combustion cycle (1) proceeds based on a predetermined characteristic for each of the various injection modes, wherein the limit value calculation unit (29) calculates the limit value (GaL) to gradually increase as the correction coefficient (K) decreases.
  2. 2. Apparatus (100) according to claim 1, characterized in that the plurality of injection modes includes a plurality of normal injection modes to be alternated according to the operating state of the engine (1) after the activation of the engine (1) is completed, wherein the limit value calculation unit (29) calculates the limit value (GaL) to gradually increase as the correction coefficient (K) in a mode in which the correction coefficient (K) is the largest among the plurality of normal injection modes decreases.
  3. 3. Apparatus (100), according to claim 2, characterized in that the plurality of normal injection modes includes: a first mode to be switched when a rotation speed (Ne) of the engine (1) is equal to or greater than a first limit (Ne1) and less than a second limit (Ne2); a second mode to be switched when the rotation speed (Ne) is equal to or greater than the second limit (Ne2) and less than a third limit (Ne3); and a third mode to be switched when the rotation speed (Ne) is equal to or greater than the third limit (Ne3).
  4. 4. Apparatus (100), according to claim 3, characterized in that in the first mode, the fuel is injected a plurality of times in a compression stroke of the engine (1), in the second mode, the fuel is injected in the intake stroke of the engine (1) and in the compression stroke, in the third mode, the fuel is injected in the intake stroke, in the third mode being the mode in which the correction coefficient (K) is the largest among the plurality of normal injection modes.
  5. 5. Apparatus (100), according to claim 1, characterized in that the plurality of injection modes includes a plurality of normal injection modes to be alternated according to the operating state of the engine (1) after the activation of the engine (1) is completed, wherein the limit value calculation unit (29) calculates the limit value (GaL) to gradually increase as the correction coefficient (K) in a mode in which the correction coefficient (K) is the largest among the plurality of normal injection modes decreases when an engine load (1) is equal to or greater than a limit (α).
  6. 6. Apparatus (100), according to claim 1, characterized in that the fuel is fuel containing alcohol.

Description

BACKGROUND OF THE INVENTION Field of Invention [001] The present invention relates to a control apparatus for an internal combustion engine. Description of the Related Technique [002] In recent years, research and development has been carried out on direct injection internal combustion engines, contributing to energy efficiency and enabling more people to access affordable, reliable, sustainable, and advanced energy. As a technology, a device that controls fuel injection immediately after the activation of a direct injection internal combustion engine is conventionally known. For example, in the device described in document JP2006-183537 A, until a predetermined period has elapsed from activation, when fuel is injected multiple times, a correction coefficient for increasing the amount of fuel injected, in order to compensate for insufficient vaporization of the fuel when cold, is defined as being greater than when the fuel is injected collectively. Then, after the predetermined period, when injecting the fuel collectively, the correction coefficient for increasing the amount of fuel is defined as being greater than when the fuel is injected multiple times. [003] When a fuel injection quantity increase correction is made as the apparatus described in document JP2006-183537A, however, the end of fuel injection (End Of Injection (EOI)) is shifted to a retard side, and the injected fuel is not partially vaporized enough before the ignition point, which can lead to misfire. SUMMARY OF THE INVENTION [004] One aspect of the present invention is a control apparatus for an internal combustion engine, including: an injection mode switching unit configured to switch an injection mode for injecting fuel into the engine's combustion chamber to one of a plurality of injection modes, according to the engine's operating state; a correction coefficient calculation unit configured to calculate a correction coefficient to increase a reference injection fuel quantity, calculated according to the engine's operating state, for a predetermined period from the moment of starting an engine activation; and a limit value calculation unit configured to calculate a limit value of the engine intake quantity for the predetermined period. The correction coefficient calculation unit calculates the correction coefficient to gradually decrease as the engine's combustion cycle progresses, based on a predetermined characteristic for each of the plurality injection modes. The limit value calculation unit calculates the limit value to gradually increase as the correction coefficient decreases. BRIEF DESCRIPTION OF THE DRAWINGS [005] The objects, features and advantages of the present invention will become clearer from the following embodiments in relation to the accompanying drawings, in which: Figure 1 is a view that schematically illustrates an example of the main configurations of an engine, to which an internal combustion engine control apparatus is applied according to an embodiment of the present invention; Figure 2 is a block diagram that schematically illustrates an example of a general configuration of the internal combustion engine control apparatus according to the embodiment of the present invention; Figure 3 is a diagram to describe a first mode, a second mode and a third mode of the normal mode alternated by an injection mode switching unit of Figure 2; Figure 4 is a diagram to describe an example of a limit value calculated by a limit value calculation unit of Figure 2; Figure 5A is a diagram to describe another example of the limit value calculated by the limit value calculation unit of Figure 2, in a case where the injection mode is alternated from the injection mode in which a correction coefficient of the quantity of The fuel injection is relatively small for the injection mode in which the correction coefficient is relatively large; Figure 5B is a diagram to describe another example of the limit value calculated by the limit value calculation unit of Figure 2, in a case where the injection mode is switched from the injection mode in which the correction coefficient is relatively large to the injection mode in which the correction coefficient is relatively small; and Figure 6 is a diagram to describe yet another example of the limit value calculated by the limit value calculation unit of Figure 2. DETAILED DESCRIPTION OF THE INVENTION [006] The following will describe embodiments of the present invention with reference to Figures 1 to 6. A control apparatus for an internal combustion engine, according to one embodiment of the present invention, is applicable to a spark-ignition type internal combustion engine with direct injection. In particular, a description will be given with respect to an example applied to a spark-ignition type internal combustion engine with direct injection, mounted in a vehicle supplied with an alcohol-containing fuel, such as bioethanol. [007] Figure 1 is a schematic view illustrating an example of th