System for controlling an air-fuel ratio

Patent · Tue Jul 19 04:00:00 EDT 1983

OSTI ID:5416938

Kataoka, R

A method and system are disclosed for controlling the air-fuel ratio for a carburetor for an internal combustion engine having an intake passage, an exhaust passage, a throttle valve, a detector for detecting the concentration of a constituent of the exhaust gases, an on-off type electromagnetic valve for correcting the air-fuel ratio of the air-fuel mixture supplied by an air-fuel mixture supplier and an electronic controller. The electronic controller comprises a comparing circuit for comparing the output signal of the detector with a stoichiometric reference signal, for driving the on-off electro-magnetic valve for controlling the air-fuel ratio to a value approximating the stoichiometric air-fuel ratio. A switch connects a constant signal generating circuit to the electronic controller and renders the electronic control means nonresponsive to the detector when a vacuum sensor actuates the switch during a rapid deceleration, whereby the on-off electro-magnetic valve operates by the constant signal from the constant signal generating circuit at a predetermined duty ratio to prevent an excessive enrichment of the mixture caused by misfiring.

• Assignee: Fuji Jukogyo Kabushiki Kaisha (Japan); Nissan Motor Co., Ltd. (Japan)
• Patent Number(s): US 4393839
• OSTI ID: 5416938
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
CARBURETORS
COMPARATOR CIRCUITS
CONTROL SYSTEMS
DETECTION
ELECTRONIC CIRCUITS
ENGINES
EXHAUST GASES
FLUIDS
FUEL SYSTEMS
FUEL-AIR RATIO
GASEOUS WASTES
GASES
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
SIGNALS
WASTES