The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Jun. 06, 2006

Filed:

Oct. 12, 2004
Applicant:

Eiji Hashimoto, Saitama, JP;

Inventor:

Eiji Hashimoto, Saitama, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F01N 3/00 (2006.01);
U.S. Cl.
CPC ...
Abstract

A high precision deterioration determination device for an exhaust gas purifier of an engine is provided. The engine includes an exhaust gas purifier disposed in an exhaust pipe of the engine, and a downstream exhaust gas sensor disposed in the exhaust pipe on the downstream of the purifier for generating outputs corresponding to components of an exhaust gas. The electronic control unit controls an air/fuel ratio of the engine to a predetermined value based on the outputs of the downstream exhaust gas sensor. The control unit is programmed to perform a non-linear filtering to extract rectangle-shaped waveform components from the outputs of the downstream exhaust gas sensor. The control unit subtracts the rectangle-shaped waveform components from the sensor outputs to extract noise components representing a degree of the catalyst deterioration.


Find Patent Forward Citations

Loading…