Power plants – Internal combustion engine with treatment or handling of... – Methods
Patent
1992-08-04
1994-06-14
Hart, Douglas
Power plants
Internal combustion engine with treatment or handling of...
Methods
60276, 60277, 60285, 123691, F01N 320
Patent
active
053199219
ABSTRACT:
Apparatus and method are disclosed for monitoring catalytic converter efficiency in treating exhaust gas from an internal combustion engine having fuel control means for controlling the air/fuel ratio at which fuel is supplied to the engine in response to a fuel flow control signal. During normal operation mode, control signal means generate the fuel flow control signal based at least in part on output signals from first and second EGO sensors exposed to the exhaust gas upstream and downstream, respectively, of the catalytic converter. During a test operation mode, preferably initiated and carried out during substantially steady state or normal operation of the engine, the output signal from the upstream EGO sensor is replaced by a zero mean value periodic function test signal. The output signal of the second (i.e., downstream) EGO sensor is compared to a stored value corresponding to minimum acceptable efficacy of the catalytic converter. For example, a value may be pre-stored and compared to the integral over the test interval of the absolute value of signal deviation from stoichiometry, preferably weighted or normalized, e.g., by dividing it by the integral over the test interval of the absolute value of fuel pulse width deviation from steady state. A failure signal is generated when the comparison indicates efficacy below the minimum acceptable level.
REFERENCES:
patent: 3939654 (1976-02-01), Creps
patent: 3962866 (1976-06-01), Neidhard et al.
patent: 3969932 (1976-07-01), Rieger et al.
patent: 4007589 (1977-02-01), Neidhard et al.
patent: 4027477 (1977-06-01), Storey
patent: 4121548 (1978-10-01), Hattori et al.
patent: 4251990 (1981-02-01), Norimatsu et al.
patent: 4622809 (1986-11-01), Abthoff et al.
patent: 4831838 (1989-05-01), Nagai et al.
patent: 4840027 (1989-06-01), Okumura
patent: 5077970 (1992-01-01), Hamburg
Clemens et al -SAE Technical Paper 900062, Detection of Catalyst Performance Loss Using On-Board Diagnostics, Feb. 26-Mar. 2, 1990.
Ford Motor Company
Hart Douglas
Malleck Joseph W.
May Roger L.
LandOfFree
Catalytic converter efficiency monitoring does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Catalytic converter efficiency monitoring, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Catalytic converter efficiency monitoring will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1239714