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
Document layout method
Submersible remote smoke sensor
Image forming apparatus having exhaust fan
Media used in digital high speed inkjet web press printing
Information processing apparatus and display control method
Device, system, and method for logging near field communications tag interactions
Semiconductor device including a clock generating circuit for generating an internal signal having a coarse delay line, a fine delay line and a selector circuit
  Randomly Featured Patents
Braking pressure generator for a vacuum operated brake system with anit-lock control
Surface acoustic wave device employing reflectors
Flame sensor and method of using same
Skimmed charge capture and charge packet removal for increased effective pixel photosensor full well capacity
Optical probe microscope having a fiber optic tip that receives both a dither motion and a scanning motion, for nondestructive metrology of large sample surfaces
Image sensing apparatus, signal processing method thereof, program, and storage medium
Combinations of sparingly soluble calcium phosphates in slurries and pastes as mineralizers and cements
Highly branched amino hexahydropyridines
Resistance welding control system
Micro-computer control for a video machine