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.
Patent No.:
Date of Patent:
Mar. 31, 1998
Filed:
Jun. 20, 1996
Siemens Aktiengesellschaft, Munich, DE;
Bayerische Motoren Werke Aktiengesellschaft, Munich, DE;
Abstract
In a method for checking the conversion capability of a catalytic converter, in particular a precatalytic converter associated with internal combustion engines of motor vehicles, the checking is undertaken through the use of a temperature measurement immediately downstream of the catalytic converter. Initially the temperature at the beginning and at the end of a predetermined idling phase is measured for a predetermined number of idling phases, following an overrun phase in predetermined operating states of a motor vehicle with an internal combustion engine. Then the difference of the temperature measurements for each idling phase is formed. The sum of all of the temperature differences and the sum of the duration of the idling phases are formed and subsequently a quotient of these results is formed. This quotient determines an average gradient. The average gradient determined in this way is compared with a limiting value and the catalytic converter is recognized as defective if the predetermined limiting value is exceeded. The method may be applied to motor vehicles with internal combustion engines.