Fuel injection control system for internal combustion engines

• US 5,601,064 A
• Filed: 10/26/1995
• Issued: 02/11/1997
• Est. Priority Date: 10/27/1994
• Status: Expired due to Term

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Taniguchi, Yutaka, Sato, Ryuji, Kitamura, Toru, Fujimoto, Sachito, Tsujii, Keiji
• Primary Examiner(s): Wolfe, Willis R.
• Application Number:
  US08/548,486
• Time in Patent Office: 474 Days
• Field of Search: 123/478, 123/480, 123/491, 123/492, 123/493, 123/179.16
• US Class Current: 123/491
• 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 41/06 for engine starting or warming up F02D41/0255 takes precedence

Abstract

A fuel injection control system for an internal combustion engine includes an ECU which carries out adherent fuel-dependent correction by calculating an amount of fuel to be injected into the intake passage such that a sum of a direct supply amount of fuel directly drawn into the combustion chamber of the engine without adhering to the wall surface of the intake passage out of a whole amount of fuel injected into the intake passage, and a carried-off amount of fuel carried off the wall surface of the intake passage into the combustion chamber out of fuel adhering to the wall surface of the intake passage is equal to a required fuel amount for the engine. The starting condition of the engine is detected by sensors, and operation of the adherent fuel-dependent correction control is limited during the starting condition of the engine. The carried-off fuel amount is set to a predetermined value, based on at least one operating parameter of the engine when the engine has shifted from the starting condition to the basic operating condition after starting.

Claims

1. In a fuel injection control system for an internal combustion engine having an intake passage having a wall surface, and at least one combustion chamber, including adherent fuel-dependent correction control means for carrying out adherent fuel-dependent correction by calculating an amount of fuel to be injected into said intake passage such that a sum of a direct supply amount of fuel directly drawn into said combustion chamber of said engine without adhering to said wall surface of said intake passage out of a whole amount of fuel injected into said intake passage, and a carried-off amount of fuel carried off said wall surface of said intake passage into said combustion chamber out of fuel adhering to said wall surface of said intake passage is equal to a required fuel amount for said engine,

the improvement comprising:

engine start-detecting means for detecting a starting condition of said engine;

adherent fuel-dependent correction control-limiting means for limiting operation of said adherent fuel-dependent correction control during said starting condition of said engine; and

carried-off fuel amount-setting means for setting said carried-off fuel amount to a predetermined value based on at least one operating parameter of said engine when said engine has shifted from said starting condition to a basic operating condition after starting.

2. A fuel injection control system as claimed in claim 1, wherein said at least one operating parameter of said engine is coolant temperature of said engine, said carried-off fuel amount-setting means setting said predetermined value to a larger value as said coolant temperature of said engine is lower.

3. A fuel injection control system as claimed in claim 1, including wall surface temperature-estimating means for estimating temperature of said wall surface of said intake passage, based on at least one operating parameter of said engine, and wherein said carried-off fuel amount-setting means sets said predetermined value to a larger value as the estimated temperature of said wall surface of said intake passage is lower.

4. A fuel injection control system as claimed in claim 1, wherein said adherent fuel-dependent correction control-limiting means sets a parameter representative of said direct supply amount of fuel to such a value that said adherent fuel-dependent correction control is carried out to a limited degree.

5. A fuel injection control system as claimed in claim 1, wherein said adherent fuel-dependent correction control means calculates said amount of fuel to be injected into said intake passage, based on said direct supply amount of fuel, said carried-off amount of fuel, and a parameter representative of a time delay with said carried-off amount of fuel is carried off into said combustion chamber, said adherent fuel-dependent correction control-limiting means setting said parameter representative of said time delay to such a value that said adherent fuel-dependent correction control is carried out to a limited degree.

6. A fuel injection control system as claimed in claim 4, wherein said adherent fuel-dependent correction control means calculates said amount of fuel to be injected into said intake passage, based on said direct supply amount of fuel, said carried-off amount of fuel, and a parameter representative of a time delay with said carried-off amount of fuel is carried off into said combustion chamber, said adherent fuel-dependent correction control-limiting means setting said parameter representative of said time delay to such a value that said adherent fuel-dependent correction control is carried out to a limited degree.

7. In a fuel injection control system for an internal combustion engine having an intake passage having a wall surface, and at least one combustion chamber, including adherent fuel-dependent correction control means for carrying out adherent fuel-dependent correction by calculating an amount of fuel to be injected into said intake passage such that a sum of a direct supply amount of fuel directly drawn into said combustion chamber of said engine without adhering to said wall surface of said intake passage out of a whole amount of fuel injected into said intake passage, and a carried-off amount of fuel carried off said wall surface of said intake passage into said combustion chamber, out of fuel adhering to said wall surface of said intake passage is equal to a required fuel amount for said engine,

the improvement comprising:

engine start-detecting means for detecting a starting condition of said engine;

adherent fuel-dependent correction control-inhibiting means for inhibiting operation of said adherent fuel-dependent correction control during said starting condition of said engine; and

carried-off fuel amount-setting means for setting said carried-off fuel amount to a predetermined value based on at least one operating parameter of said engine when said engine has shifted from said starting condition to a basic operating condition after starting.

8. A fuel injection control system as claimed in claim 7, wherein said at least one operating parameter of said engine is coolant temperature of said engine, said carried-off fuel amount-setting means setting said predetermined value to a larger value as said coolant temperature of said engine is lower.

9. A fuel injection control system as claimed in claim 7, including wall surface temperature-estimating means for estimating temperature of said wall surface of said intake passage, based on at least one operating parameter of said engine, and wherein said carried-off fuel amount-setting means sets said predetermined value to a larger value as the estimated temperature of said wall surface of said intake passage is lower.