Exhaust gas cleaning system for internal combustion engine

Patent · Tue May 29 04:00:00 EDT 1984

OSTI ID:6272678

Otani, J; Ikenoya, Y; Kato, H

An exhaust gas cleaning system for an internal combustion engine having an exhaust system leading to an exhaust port of an engine body. The exhaust gas cleaning system comprises a TWC catalyst disposed in the exhaust system for simultaneously cleaning HC, CO and NO/CHI/ in exhaust gas flowing through the exhaust system. A secondary-air supply passage is connected to the exhaust system on the upstream side of the TWC catalyst and coupled to the atmosphere. A check valve is disposed in the secondary-air supply passage, wherein the check valve is opened by the exhaust gas pulsation generated in the exhaust system and a secondary air control valve is positioned in the secondary-air supply passage on the upstream side of the check valve, wherein the secondary-air control valve increases the flow rate of the secondary air supplied to the exhaust system in the low-speed revolution range of the engine and decreases the flow rate of the secondary air supplied to the exhaust system in the accelerating and high-speed revolution ranges of the engine such that the atmosphere of the TWC catalyst becomes oxidative in the low-speed revolution range of the engine while the catalyst atmosphere becomes close to that of a stoichiometric ratio in the accelerating and high-speed revolution ranges.

• Assignee: Honda Giken Kogyo Kabushiki Kaisha (Japan)
• Patent Number(s): US 4450684
• OSTI ID: 6272678
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
330700 -- Advanced Propulsion Systems-- Emission Control
AIR FLOW
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CATALYSTS
CATALYTIC CONVERTERS
CHALCOGENIDES
CHEMICAL REACTIONS
CLEANING
CONTROL EQUIPMENT
ENGINES
EQUIPMENT
EXHAUST GASES
EXHAUST SYSTEMS
FLOW RATE
FLOW REGULATORS
FLUID FLOW
FLUIDS
GAS FLOW
GASEOUS WASTES
GASES
HEAT ENGINES
HYDROCARBONS
INTERNAL COMBUSTION ENGINES
NITROGEN COMPOUNDS
NITROGEN OXIDES
ORGANIC COMPOUNDS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL EQUIPMENT
PULSES
VALVES
WASTES