Fuel injected engine control device and method performing wall-adhered fuel accounting

• US 4,388,906 A
• Filed: 05/05/1982
• Issued: 06/21/1983
• Est. Priority Date: 07/06/1981
• Status: Expired due to Term

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Sugiyama, Shinichi, Nakatomi, Takayoshi
• Primary Examiner(s): Cox, Ronald B.
• Application Number:
  US06/375,196
• Time in Patent Office: 412 Days
• Field of Search: 123/492, 123/493, 123/480
• US Class Current: 123/492
• CPC Class Codes: F02D 41/047 Taking into account fuel evaporation or wall wetting; special correction after fuel cut-off F02D41/126

Abstract

A method for controlling an internal combustion engine with a fuel injection valve fitted to its intake manifold. Repeatedly a first quantity representing the desired amount of fuel to be supplied to the combustion chambers in the next fuel injection pulse, a second quantity representing the proportion of fuel in one pulse which will adhere to the walls of the intake system, and a third quantity representing the proportion of fuel adhering to these walls which will be sucked off into the combustion chambers between two successive pulses are determined, based upon sensed values of certain operational parameters. Simultaneously, at proper injection time points in the engine'"'"'s operational cycle, first from the third quantity and a fourth quantity representing the total fuel amount adhering to the walls a fifth quantity representing the actual fuel amount sucked off from the walls between two successive pulses is determined; then from the first, second, and fifth quantities a sixth quantity representing the actual fuel amount to be injected in the next pulse is determined; then from the sixth and second quantities a seventh quantity representing the actual amount of fuel from the next pulse that will adhere to the walls is determined; next the fourth quantity is updated by adding the seventh and subtracting the fifth quantity, and next the fuel injection valve is opened for a time corresponding to the sixth quantity. A device is also explained, incorporating an electronic computer, which practices this method.

Claims

1. For an internal combustion engine with a combustion chamber system and comprising an air-fuel mixture intake system formed with walls and comprising an intake manifold, said internal combustion engine further comprising a fuel injection valve fitted to said intake manifold which is selectively opened and closed by selective supply of an actuating signal thereto and which when so opened injects liquid fuel into said intake manifold, said internal combustion engine and said fuel injection valve operating according to an operational cycle:

an engine control method, comprising the processes, repeatedly and alternatingly and/or simultaneously performed, of;

(a) sensing the current values of certain operational parameters of said internal combustion engine;

(b) based upon the current values of said sensed operational parameters of said internal combustion engine, calculating the value of a first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points, the value of a second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system, and the value of a third quantity representing the proportion of the total amount of fuel adhering to said walls of said air-fuel mixture intake system which is sucked off therefrom to pass into said combustion chamber system of said internal combustion engine during the time interval between two successive fuel injection pulses; and

(c) at time points in said operational cycle of said internal combustion engine and said fuel injection valve which are proper fuel injection time points, performing the following processes in the specified order;

(c1) calculating, from the current value of a fourth quantity representing the total amount of fuel adhering to said walls of said air-fuel mixture intake system, and the current value of said third quantity representing the proportion of the total amount of fuel adhering to said walls of said air-fuel mixture intake system which is sucked off therefrom to pass into said combustion chamber system of said internal combustion engine during the time interval between two successive fuel injection pulses, the value of a fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it;

(c2) calculating, from the current value of said first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points, from the current value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system, and from the current value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it, the value of a sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse;

(c3) calculating, from the current value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse and the current value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system, the value of a seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system;

(c4) updating the value of said fourth quantity representing the total amount of fuel adhering to said walls of said air-fuel mixture intake system by adding thereto the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system and by subtracting from the result of this addition the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it;

(c5) modifying said actuating signal according to the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse; and

(c6) supplying said modified actuating signal to said fuel injection valve in such a fashion as to cause said fuel injection valve to open for a time period which will allow an amount of fuel approximately equal to the fuel amount represented by said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse to pass through said fuel injection valve so as to be injected into said intake manifold;

wherein the method used in subprocess (c2) for calculating the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse is such that the sum of the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse and the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it less the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system is approximately equal to the value of said first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points.

3. An engine control method according to either one of claims 1 and 2, wherein the method used for calculating the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it is to multiply the value of said fourth quantity representing the total amount of fuel adhering to said walls of said air-fuel mixture intake system by the value of said third quantity representing the proportion of the total amount of fuel adhering to said walls of said air-fuel mixture intake system which is sucked off therefrom to pass into said combustion chamber system of said internal combustion engine during the time interval between two successive fuel injection pulses.

4. An engine control method according to either one of claims 1 and 2, wherein the method used for calculating the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse is to subtract from the value of said first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse and the next fuel injection pulse after it, and to divide the result by unity less the value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system.

5. An engine control method according to claim 3, wherein the method used for calculating the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse is to subtract from the value of said first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse and the next fuel injection pulse after it, and to divide the result by unity less the value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system.

6. An engine control method according to either one of claims 1 and 2, wherein the method used for calculating the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system is to multiply the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse by the value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system.

7. An engine control method according to claim 3, wherein the method used for calculating the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system is to multiply the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse by the value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system.

8. An engine control method according to claim 4, wherein the method used for calculating the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system is to multiply the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse by the value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system.

9. An engine control method according to claim 5, wherein the method used for calculating the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system is to multiply the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse by the value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system.

2. For an internal combustion engine with a combustion chamber system and comprising an air-fuel mixture intake system formed with walls and comprising an intake manifold, said internal combustion engine further comprising a fuel injection valve fitted to said intake manifold which is selectively opened and closed by selective supply of an actuating signal thereto and which when so opened injects liquid fuel into said intake manifold, said internal combustion engine and said fuel injection valve operating according to an operational cycle:

an engine control method, comprising the processes, repeatedly and alternatingly and/or simultaneously performed, of;

(a) sensing the current values of certain operational parameters of said internal combustion engine;

(b) based upon the current values of said sensed operational parameters of said internal combustion engine, calculating the value of a first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points, the value of a second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system, and the value of a third quantity representing the proportion of the total amount of fuel adhering to said walls of said air-fuel mixture intake system which is sucked off therefrom to pass into said combustion chamber system of said internal combustion engine during the time interval between two successive fuel injection pulses; and

(c) at time points in said operational cycle of said internal combustion engine and said fuel injection valve which are proper fuel injection time points, performing the following processes in the specified order;

(c1) calculating, from the current value of a fourth quantity representing the total amount of fuel adhering to said walls of said air-fuel mixture intake system, and the current value of said third quantity representing the proportion of the total amount of fuel adhering to said walls of said air-fuel mixture intake system which is sucked off therefrom to pass into said combustion chamber system of said internal combustion engine during the time interval between two successive fuel injection pulses, the value of a fifth quantity representing the amount of fuel from the total amont of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it;

and, if according to the current operational conditions of said internal combustion engine it is proper to inject fuel through said fuel injection valve,

(c2) performing the following processes in the specified order;

(c2.1) calculating, from the current value of said first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points, from the current value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system, and from the current value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it, the value of a sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse;

(c2.2) calculating, from the current value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse and the current value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system, the value of a seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system;

(c2.3) updating the value of said fourth quantity representing the total amount of fuel adhering to said walls of said air-fuel mixture intake system by adding thereto the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system and by subtracting from the result of this addition the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it;

(c2.4) modifying said actuating signal according to the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse; and

(c2.5) supplying said modified actuating signal to said fuel injection valve in such a fashion as to cause said fuel injection valve to open for a time period which will allow an amount of fuel approximately equal to the fuel amount represented by said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse to pass through said fuel injection valve so as to be injected into said intake manifold;

but otherwise, if according to the current operational conditions of said internal combustion engine it is not proper to inject fuel through said fuel injection valve,

(c3) performing the following process;

(c3.1) updating the value of said fourth quantity representing the total amount of fuel adhering to said walls of said air-fuel mixture intake system by subtracting therefrom the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it;

wherein the method used in subprocess (c2.1) for calculating the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse is such that the sum of the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse and the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse and the next fuel injection pulse after it less the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system is approximately equal to the value of said first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points.

10. For an internal combustion engine with a combustion chamber system and comprising an air-fuel mixture intake system formed with walls and comprising an intake manifold, said internal combustion engine further comprising a fuel injection valve fitted to said intake manifold which is selectively opened and closed by selective supply of an actuating signal thereto and which when so opened injects liquid fuel into said intake manifold, said internal combustion engine and said fuel injection valve operating according to an operational cycle:

an engine control device, comprising;

(a) a plurality of sensors, which sense the current values of certain operational parameters of said internal combustion engine;

(b) an interface device, which, whenever it receives a fuel injection valve control electrical signal, dispatches said fuel injection valve actuating signal to said fuel injection valve; and

(c) an electronic computer, which receives supply of signals from said sensors indicative of said current values of said certain operational parameters of said internal combustion engine;

(d) said electronic computer repeatedly and alternatingly and/or simultaneously;

(d1) based upon the current values of said sensed operational parameters of said internal combustion engine, calculating the value of a first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points, the value of a second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system, and the value of a third quantity representing the proportion of the total amount of fuel adhering to said walls of said air-fuel mixture intake system which is sucked off therefrom to pass into said combustion chamber system of said internal combustion engine during the time interval between two successive fuel injection pulses; and

(d2) at time points in said operational cycle of said internal combustion engine and said fuel injection valve which are proper fuel injection time points, performing the following processes in the specified order;

(d2.1) calculating, from the current value of a fourth quantity representing the total amount of fuel adhering to said walls of said air-fuel mixture intake system, and the current value of said third quantity representing the proportion of the total amount of fuel adhering to said walls of said air-fuel mixture intake system which is sucked off therefrom to pass into said combustion chamber system of said internal combustion engine during the time interval between two successive fuel injection pulses, the value of a fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it;

(d2.2) calculating, from the current value of said first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points, from the current value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system, and from the current value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it, the value of a sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse;

(d2.3) calculating, from the current value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse and the current value of said second quantity representing the proportion of fuel in one pulse of fuel injected through aid fuel injection valve which will adhere to said walls of said air-fuel mixture intake system, the value of a seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system;

(d2.4) updating the value of said fourth quantity representing the total amount of fuel adhering to said walls of said air-fuel mixture intake system by adding thereto the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system and by subtracting from the result of this addition the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it; and

(d2.5) outputting to said interface device a fuel injection valve control electrical signal, based upon the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse, such as to cause said fuel injection valve to open for a time period which will allow an amount of fuel approximately equal to the fuel amount represented by said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse to pass through said fuel injection valve so as to be injected into said intake manifold;

wherein the method used by said electronic computer in subprocess (d2.2) for calculating the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse is such that the sum of the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse and the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it less the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system is approximately equal to the value of said first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points.

12. An engine control device according to either one of claims 10 and 11, wherein the method used by said electronic computer for calculating the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it is to multiply the value of said fourth quantity representing the total amount of fuel adhering to said walls of said air-fuel mixture intake system by the value of said third quantity representing the proportion of the total amount of fuel adhering to said walls of said air-fuel mixture intake system which is sucked off therefrom to pass into said combustion chamber system of said internal combustion engine during the time interval between two successive fuel injection pulses.

13. An engine control device according to either one of claims 10 and 11, wherein the method used by said electronic computer for calculating the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse is to subtract from the value of said first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse and the next fuel injection pulse after it, and to divide the result by unity less the value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system.

14. An engine control device according to claim 12, wherein the method used by said electronic computer for calculating the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse is to subtract from the value of said first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse and the next fuel injection pulse after it, and to divide the result by unity less the value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system.

15. An engine control device according to either one of claims 10 and 11, wherein the method used by said electronic computer for calculating the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system is to multiply the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse by the value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system.

16. An engine control device according to claim 12, wherein the method used by said electronic computer for calculating the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system is to multiply the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse by the value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system.

17. An engine control device according to claim 13, wherein the method used by said electronic computer for calculating the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system is to multiply the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse by the value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system.

18. An engine control device according to claim 14, wherein the method used by said electronic computer for calculating the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system is to multiply the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse by the value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system.

11. For an internal combustion engine with a combustion chamber system and comprising an air-fuel mixture intake system formed with walls and comprising an intake manifold, said internal combustion engine further comprising a fuel injection valve fitted to said intake manifold which is selectively opened and closed by selective supply of an actuating signal thereto and which when so opened injects liquid fuel into said intake manifold, said internal combustion engine and said fuel injection valve operating according to an operational cycle:

an engine control device, comprising;

(a) a plurality of sensors, which sense the current values of certain operational parameters of said internal combustion engine;

(b) an interface device, which, whenever it receives a fuel injection valve control electrical signal, dispatches said fuel injection valve actuating signal to said fuel injection valve; and

(c) an electronic computer, which receives supply of signals from said sensors indicative of said current values of said certain operational parameters of said internal combustion engine;

(d) said electronic computer repeatedly and alternatingly and/or simultaneously;

(d1) based upon the current values of said sensed operational parameters of said internal combustion engine, calculating the value of a first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points, the value of a second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system, and the value of a third quantity representing the proportion of the total amount of fuel adhering to said walls of said air-fuel mixture intake system which is sucked off therefrom to pass into said combustion chamber system of said internal combustion engine during the time interval between two successive fuel injection pulses; and

(d2) at time points in said operational cycle of said internal combustion engine and said fuel injection valve which are proper fuel injection time points, performing the following processes in the specified order;

(d2.1) calculating, from the current value of a fourth quantity representing the total amount of fuel adhering to said walls of said air-fuel mixture intake system, and the current value of said third quantity representing the proportion of the total amount of fuel adhering to said walls of said air-fuel mixture intake system which is sucked off therefrom to pass into said combustion chamber system of said internal combustion engine during the time interval between two successive fuel injection pulses, the value of a fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it;

and, if according to the current operational conditions of said internal combustion engine it is proper to inject fuel through said fuel injection valve,

(d2.2) performing the following processes in the specified order;

(d2.2.1) calculating, from the current value of said first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points, from the current value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system, and from the current value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it, the value of a sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse;

(d2.2.2) calculating, from the current value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse and the current value of said second quantity representing the proportion of fuel in one pulse of fuel injected through said fuel injection valve which will adhere to said walls of said air-fuel mixture intake system, the value of a seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system;

(d2.2.3) updating the value of said fourth quantity representing the total amount of fuel adhering to said walls of said air-fuel mixture intake system by adding thereto the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system and by subtracting from the result of this addition the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it;

(d2.2.4) modifying said actuating signal according to the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse; and

(d2.2.5) outputting to said interface device a fuel injection valve control electrical signal, based upon the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse, such as to cause said fuel injection valve to open for a time period which will allow an amount of fuel approximately equal to the fuel amount represented by said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse to pass through said fuel injection valve so as to be injected into said intake manifold;

but otherwise, if according to the current operational conditions of said internal combustion engine it is not proper to inject fuel through said fuel injection valve,

(d2.3) performing the following process;

(d2.3.1) updating the value of said fourth quantity representing the total amount of fuel adhering to said walls of said air-fuel mixture intake system by subtracting therefrom the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse time instant and the next fuel injection pulse time instant after it;

wherein the method used by said electronic computer in subprocess (d2.2.1) for calculating the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse is such that the sum of the value of said sixth quantity representing the actual fuel amount to be injected through said fuel injection valve in the next fuel injection pulse and the value of said fifth quantity representing the amount of fuel from the total amount of fuel adhering to said walls of said air-fuel mixture intake system which will be sucked off therefrom to pass into said combustion chamber system of said internal combustion engine in the time interval between the next fuel injection pulse and the next fuel injection pulse after it less the value of said seventh quantity representing the amount of fuel from the next fuel injection pulse that will adhere to said walls of said air-fuel mixture intake system is approximately equal to the value of said first quantity representing the desired amount of fuel to be provided to said combustion chamber system of said internal combustion engine during the time period between the next two fuel injection pulse time points.