Resources Contact Us Home
Catalyst deterioration-determining device for an internal combustion engine

Image Number 4 for United States Patent #5448886.

A catalyst deterioration-determining device for an internal combustion engine having first and second exhaust sensors positioned in an exhaust path of the internal combustion engine upstream downstream, respectively, of a catalyzer located in the exhaust path. The internal combustion engine further including a control station for effecting feedback control to match an air-fuel ratio with a desired value in accordance with first and second detection signals from the first and second exhaust sensors, respectively. The catalyst deterioration-determining device including a determining section provided in the control station which obtains a deterioration-determined value from calculations based on a rich determination delay time, a lean determination delay time, a lean response delay time and a rich response delay time when a deteriorated state of the catalyzer is determined. The lean response delay time and the rich response delay time extend from the beginning of a decrease and an increase in the first feedback control-corrected quantity to a lean inversion time and a rich inversion time of the second detection signal in response to rich and lean inversions of the first detection signal. The rich determination delay time and the lean determination delay time extend from a rich inversion time and a lean inversion time of the first detection signal to the beginning of the decrease and increase in the feedback control-corrected quantity. The determining section performs calculations in accordance with the deterioration-determined value to determine the deteriorated state of the catalyzer.

  Recently Added Patents
Management of temporal data by means of a canonical schema
System and method for burst separation and extended interleaving length
Strap-hook ring
Deposited conductive layers for leads of implantable electric stimulation systems and methods of making and using
Enediyne compounds, conjugates thereof, and uses and methods therefor
System and method for a TCP mapper
Ejection station
  Randomly Featured Patents
Cutting means for book binding machine
Conveyor chain
Computerized control of multi-size spot beam imaging
High contrast scanner photographic elements employing ruthenium and iridium dopants
Power supply circuit
Low-cost universal drive for use with switched reluctance machines
Combination rafter square and level
Method for setting pitch on a windmill airfoil
Pattern voice coil transducer having permanent magnet plates of a single polarity
Exhaust gas turbocharger for an internal combustion engine