Air-fuel ratio control system

Patent · Tue Dec 13 04:00:00 EST 1983

OSTI ID:6638413

Kubota, M; Kudo, I; Ohgami, M

An air-fuel ratio control system is disclosed for an internal combustion engine having an emission control system with a three-way catalytic converter for controlling the air-fuel ratio in accordance with the temperature of the engine and operation of the engine. A temperature sensor for detecting the engine temperature and a negative pressure sensor for detecting the engine manifold vacuum in the induction passage are provided. A feedback control circuit is provided for controlling the air-fuel ratio to the stoichiometric air-fuel ratio in a normal operating condition and for stopping the control operation when the acceleration in the cold engine is detected by the temperature sensor and the negative pressure sensor. A first switch is provided to be actuated by the output of the negative pressure sensor to connect the output of the temperature sensor with the input of the feedback control circuit when the negative pressure is lower than a predetermined value. A second switch is provided to be actuated by the output of the negative pressure sensor to render the feedback control circuit inoperative as a feedback controller, whereby the air-fuel ratio is controlled by the output of the temperature sensor.

• Assignee: Fuji Jukogyo Kabushiki Kaisha (Japan); Nissan Motor Co., Ltd. (Japan)
• Patent Number(s): US 4419975
• OSTI ID: 6638413
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
330700 -- Advanced Propulsion Systems-- Emission Control
CATALYTIC CONVERTERS
CONTROL SYSTEMS
ENGINES
EQUIPMENT
FEEDBACK
FUEL-AIR RATIO
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
POLLUTION CONTROL EQUIPMENT