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:
Jul. 28, 2009
Filed:
Feb. 11, 2008
Klaus Herz, Flein, DE;
Ingo Fecht, Ludwigsburg, DE;
Klaus Herz, Flein, DE;
Ingo Fecht, Ludwigsburg, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A method and device for diagnosing a crankcase ventilation of an internal combustion engine, which enable a diagnosis of a malfunction of an actuator of the crankcase ventilation. The internal combustion engine has at least two cylinder banks to which the crankcase ventilation is supplied, and an actuator is provided via whose position the distribution of the crankcase ventilation to the at least two cylinder banks is influenced. In a first position of the actuator, a different distribution of the crankcase ventilation to the at least two cylinder banks comes about than in a second position of the actuator that differs therefrom. Given simultaneously activated operation of the at least two cylinder banks, the actuator is switched over at least one between the two different positions. For at least one of the at least two cylinder banks, a characteristic variable of the internal combustion engine influenced by the crankcase ventilation is determined prior to and following the switchover operation. A minimum value for a change in the characteristic variable of at least one of the at least two cylinder banks and/or the ratio of the characteristic variable between the at least two cylinder banks is specified for the switchover-related change in the distribution of the crankcase ventilation to the at least two cylinder banks. A malfunction of the actuator is detected if at least one change derived from the ascertained values for the characteristic variable undershoots its assigned expected minimum value in quantitative terms.