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:
Jan. 31, 1995
Filed:
Jun. 11, 1993
AFT Atlas Fahrzeugtechnik GmbH, Werdohl, DE;
Abstract
A system for monitoring suction leakage of external air into the exhaust gas path of an internal combustion engine during intermittent reduced pressure phases of the engine, during operation, includes an oxygen concentration sensing lambda probe arranged in the path. The probe issues an output signal having a reduced pressure phase pulsation frequency component of reduced pressure phase amplitude indicative of such oxygen concentration during the reduced pressure phases. The output signal is fed to a control device which generates an error signal when that amplitude exceeds a predetermined threshold level indicative of suction entry of external air into the path during a reduced pressure phase.