Air-fuel ratio control device of an internal combustion engine

Patent · Tue May 30 04:00:00 EDT 1989

OSTI ID:5829471

Uranishi, K; Itou, T

An internal combustion engine having at least one cylinder, an intake passage and an exhaust passage, the engine consists of: a carburetor arranged in the intake passage and having a fuel passage which is open to the intake passage; an electric air-fuel ratio control valve controlling an air-fuel ratio of an air-fuel mixture fed into the cylinder in response to an electric control signal, the air-fuel ratio of the air-fuel mixture increasing as a level of the electric control signal arises; an oxygen concentration detector arranged in the exhaust passage to produce a lean signal when the air-fuel ratio of the air-fuel mixture fed into the cylinder is larger than a predetermined air-fuel ratio and to produce a rich signal when the air-fuel ratio of the air-fuel mixture is smaller than the predetermined air-fuel ratio; first control means controlling the level of the electric control signal in response to the lean signal and the rich signal to raise the level of the electric control signal when the rich signal is produced and lower the level of the electric control signal when the lean signal is produced; a charcoal canister containing activated carbon therein; a fuel vapor passage connecting the charcoal canister to the intake passage; second control means for increasing the air-fuel ratio of air-fuel mixture; and third control means actuating the second control means in response to the level of the electric control signal to increase the air-fuel ratio of the air-fuel mixture after the level of the electric control signal is raised and reaches a predetermined upper level.

• Assignee: Toyota Jidosha Kabushiki Kaisha, Toyota
• Patent Number(s): US 4834050
• OSTI ID: 5829471
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
99 GENERAL AND MISCELLANEOUS
990220 -- Computers
Computerized Models
& Computer Programs-- (1987-1989)
ACTUATORS
CARBURETORS
COMPUTERIZED CONTROL SYSTEMS
CONTROL EQUIPMENT
CONTROL SYSTEMS
ENGINES
EQUIPMENT
FLOW REGULATORS
FUEL SYSTEMS
FUEL-AIR RATIO
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
MEASURING INSTRUMENTS
METERS
VALVES