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:
Nov. 09, 1999
Filed:
Jun. 30, 1997
Osamu Matsuno, Kanagawa-ken, JP;
Hiroshi Abe, Kanagawa-ken, JP;
Nissan Motor Co., Ltd., Kanagawa-ken, JP;
Abstract
Faults in a variable valve timing mechanism can be accurately diagnosed without influence of a detection error by a crank angle sensor and the like. A phase difference of a crank angle between a standard angular signal REF output from the crank angle sensor and a phase detection signal detected at a predetermined angular position of a cam shaft is counted every control state of the variable valve timing mechanism. Next, a variation between a phase difference counted at a time of OFF control state and a phase difference counted at a time of ON control state is calculated as a diagnosis parameter. Then, in the case that the diagnosis parameter is smaller than a standard value for determination, a fault in the variable valve timing mechanism is determined.