Method and apparatus for detection of catalyst failure on-board a motor vehicle using a dual oxygen sensor and an algorithm

Patent · Tue Jul 20 00:00:00 EDT 1993

OSTI ID:6337600

Clemmens, W B; Koupal, J W; Sabourin, M A

Apparatus is described for detecting motor vehicle exhaust gas catalytic converter deterioration comprising a first exhaust gas oxygen sensor adapted for communication with an exhaust stream before passage of the exhaust stream through a catalytic converter and a second exhaust gas oxygen sensor adapted for communication with the exhaust stream after passage of the exhaust stream through the catalytic converter, an on-board vehicle computational means, said computational means adapted to accept oxygen content signals from the before and after catalytic converter oxygen sensors and adapted to generate signal threshold values, said computational means adapted to compare over repeated time intervals the oxygen content signals to the signal threshold values and to store the output of the compared oxygen content signals, and in response after a specified number of time intervals for a specified mode of motor vehicle operation to determine and indicate a level of catalyst deterioration.

• Assignee: Environmental Protection Agency, Washington, DC (United States)
• Patent Number(s): US 5228335; A
• Application Number: PPN: US 7-660654
• OSTI ID: 6337600
• Resource Relation: Patent File Date: 25 Feb 1991
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
33 ADVANCED PROPULSION SYSTEMS
CATALYTIC CONVERTERS
PERFORMANCE
EXHAUST GASES
AIR POLLUTION CONTROL
MEASURING INSTRUMENTS
DESIGN
ALGORITHMS
OXYGEN
VEHICLES
CONTROL
ELEMENTS
EQUIPMENT
FLUIDS
GASEOUS WASTES
GASES
MATHEMATICAL LOGIC
NONMETALS
POLLUTION CONTROL
POLLUTION CONTROL EQUIPMENT
WASTES
540120* - Environment
Atmospheric- Chemicals Monitoring & Transport- (1990-)
330700 - Advanced Propulsion Systems- Emission Control