Internal combustion engine controls for reduced exhausts contaminants

Patent · Tue Jun 04 00:00:00 EDT 1974

OSTI ID:7232438

Matthews, Jr, D R

An electrochemical control system for achieving optimum efficiency in the catalytic conversion of hydrocarbon and carbon monoxide emissions from internal combustion engines is described. The system automatically maintains catalyst temperature at a point for maximum pollutant conversion by adjusting ignition timing and fuel/air ratio during warm-up and subsequent operation. Ignition timing is retarded during engine warm-up to bring the catalytic converter to an efficient operating temperature within a minimum period of time. After the converter reaches a predetermined minimum temperature, the spark is advanced to within its normal operating range. A needle-valve adjustment during warm-up is employed to enrich the fuel/air mixture by approximately 10 percent. Following warm-up and attainment of a predetermined catalyst temperature, the needle valve is moved automatically to its normal position (e.g., a fuel/air ratio of 16:1). Although the normal lean mixture causes increased amounts of nitrogen oxide emissions, present NO/sub x/ converters appear capable of handling the increased emissions under normal operating conditions.

• Assignee: APA; EDB-77-050115
• Patent Number(s): US 3818877
• OSTI ID: 7232438
• Resource Relation: Patent File Date: Filed date 17 Aug 1972
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
CATALYTIC CONVERTERS
CONTROL SYSTEMS
INTERNAL COMBUSTION ENGINES
AIR POLLUTION CONTROL
CARBON MONOXIDE
DESIGN
FUEL-AIR RATIO
HYDROCARBONS
IGNITION
START-UP
TEMPERATURE CONTROL
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CONTROL
ENGINES
EQUIPMENT
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL
POLLUTION CONTROL EQUIPMENT
330702* - Emission Control- Carbon Monoxide
330704 - Emission Control- Hydrocarbons