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:
Aug. 17, 1999
Filed:
Jan. 05, 1998
Applicant:
Inventor:
Tatsuo Matsumura, Atsugi, JP;
Assignee:
Unisia Jecs Corporation, Atsugi, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F01L / ;
U.S. Cl.
CPC ...
123 9015 ; 123 9017 ; 123 9031 ;
Abstract
In an apparatus for variably controlling valve timing of engine by generating, between a crankshaft and a cam shaft, a phase difference which periodically varies in a manner synchronized with a rotational phase of the cam shaft: actual phase differences are obtained at two discrete rotational phases of the cam shaft, respectively; there is assumingly calculated an amount of deviation (phase deviation .theta.) of phase difference relative to the rotational phase of the cam shaft; and the phase difference is feedback controlled based on that value of the detected phase difference which is corrected in accordance with the amount of deviation (phase deviation .theta.).