Control system for promoting catalytic removal of noxious components from exhaust gas of internal combustion engine

Patent · Tue Nov 08 04:00:00 EST 1977

OSTI ID:5283961

Nakamura, K; Sanbuichi, H

With respect to an internal combustion engine equipped with a carburetor and a catalytic converter which feeds the engine with a stoichiometric air/fuel mixture, the control system is for regulating the air/fuel ratio produced in the carburetor and comprises an auxiliary air admitting passage connected to the fuel discharge passage of the carburetor in addition to a usual air bleed passage for the fuel discharge passage, an electromagnetic valve for controlling the admission of air into the auxiliary passage, an oxygen sensor disposed in the exhaust system upstream of the catalytic converter, and a control circuit for producing continual pulses at a frequency between 5 and 100 Hz. The widths of the individual pulses are increased gradually while the output of the oxygen sensor indicates the air/fuel ratio being below the stoichiometric ratio, and vice versa. The valve is opened as each pulse is applied thereto so that the air feedrate to the fuel in the fuel passage is momentarily augmented by admission of air into the auxiliary passage.

• Assignee: Nissan Motor Co., Ltd.
• Patent Number(s): US 4056932
• OSTI ID: 5283961
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330701* -- Emission Control-- Nitrogen Oxides
330702 -- Emission Control-- Carbon Monoxide
330704 -- Emission Control-- Hydrocarbons
AIR
AIR POLLUTION CONTROL
CATALYTIC CONVERTERS
CONTROL EQUIPMENT
CRYOGENIC FLUIDS
ELEMENTS
ENGINES
EXHAUST GASES
EXHAUST SYSTEMS
FLOW REGULATORS
FLUIDS
FUEL SYSTEMS
FUEL-AIR RATIO
GASEOUS WASTES
GASES
INTERNAL COMBUSTION ENGINES
MONITORING
NONMETALS
OXYGEN
POLLUTION CONTROL
POLLUTION CONTROL EQUIPMENT
VALVES
WASTES