METHOD FOR DETECTING ABNORMALITY OCCURRED IN EXHAUST GAS CLARIFICATION DEVICE

Title:

METHOD FOR DETECTING ABNORMALITY OCCURRED IN EXHAUST GAS CLARIFICATION DEVICE

Document Type and Number:

WIPO Patent Application WO/2006/009195

Kind Code:

A1

Abstract:

A method for detecting abnormality occurred in an exhaust gas clarification device in which a reducing agent (urea water (17)) is added to a selective reduction type catalyst (10) arranged on the way of a discharge pipe (9), to thereby reduce and clarify NO_x, which comprises monitoring the temperature of the catalyst during an operation period and recording the cumulative time for each temperature range, determining the coefficient of deterioration of the ability for reducing NO_x based on the cumulative time for the each temperature range, multiplying the standard NO_xreduction ratio being in advance decided for each temperature range by the above deterioration coefficient for each temperature range, to thereby renew the above standard NO_xreduction ratio, and, in the next operation, comparing the measured NO_xreduction ratio with the above renewed standard NO_xreduction ratio for the measured temperature range, and deciding that something wrong has occurred when the deviation between the standard NO_xreduction ratio and the measured NO_xreduction ratio does not fall within the required range. The above method allows abnormality occurred in the above system for clarifying NO_x to be detected with high reliablity.

Inventors:

TSUMAGARI ICHIRO (JP)

Application Number:

PCT/JP2005/013364

Publication Date:

January 26, 2006

Filing Date:

July 21, 2005

Export Citation:

Click for automatic bibliography generation Help

Assignee:

HINO MOTORS LTD (JP)
TSUMAGARI ICHIRO (JP)

International Classes:

F01N3/18; B01D53/94; F01N3/20

Foreign References:

JP2002256951A	2002-09-11
JP2000213335A	2000-08-02
JP2002273176A	2002-09-24
JP2002221028A	2002-08-09
JP2000356127A	2000-12-26

Other References: