Air intake side secondary air supply system for an internal combustion engine with a duty ratio control operation

Patent · Tue Sep 01 04:00:00 EDT 1987

OSTI ID:6096639

Kawanabe, T; Asakura, M; Shina, T; Matsumoto, Y; Muroya, M

An air intake side secondary air supply system is described for an internal combustion engine having an air intake passage with a carburetor and an exhaust passage, comprising: an air intake side secondary air supply passage communicating with the air intake passage on the downstream side of the carburetor; an open/close valve disposed in the air intake side secondary air supply passage; an oxygen concentration sensor disposed in the exhaust passage; and detection and control means for detecting whether an air-fuel ratio of mixture to be supplied to the engine is leaner or richer with respect to a target air-fuel ratio through a level of an output signal of the oxygen concentration sensor and for periodically actuating the open/close valve, the detection and control means decreasing a valve open period of the open/close valve within each cyclic period by a first predetermined amount when a detected air-fuel ratio of mixture is leaner than the target air-fuel ratio and increasing the valve open period by a second predetermined amount when the detected air-fuel ratio of mixture is richer than the target air-fuel ratio. The second predetermined amount is different from the first predetermined amount.

• Assignee: Honda Giken Kogyo Kabushiki Kaisha, Tokyo
• Patent Number(s): US 4690121
• OSTI ID: 6096639
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
AIR FLOW
CARBURETORS
CONTROL EQUIPMENT
CONTROL SYSTEMS
ELECTRONIC CIRCUITS
ENGINES
EQUIPMENT
EXHAUST SYSTEMS
FLOW REGULATORS
FLUID FLOW
FUEL SYSTEMS
FUEL-AIR RATIO
GAS FLOW
HEAT ENGINES
INTAKE STRUCTURES
INTERNAL COMBUSTION ENGINES
MEASURING INSTRUMENTS
MECHANICAL STRUCTURES
METERS
OXYGEN METERS
SIGNALS
VALVES