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. 05, 2003
Filed:
Jul. 18, 2002
Nissan Motor Co., Ltd., Yokohama, JP;
Abstract
The trunnion ( ) of a vehicle toroidal continuously variable transmission is displaced by a step motor ( ) via a control valve ( ) and oil pressure servo cylinder ( ) in order to vary a speed ratio of the transmission. A controller ( ) calculates a target value (z*) of a control variable (z) based on an accelerator pedal depression amount (APS) and output disk rotation speed (&ohgr; ) (S ). Further, a time-variant coefficient (f) showing the relation between the trunnion displacement (y) and variation rate ({dot over (&phgr;)}) of the gyration angle (&phgr;) of the power roller, is calculated (S ). The error between the speed change response of the transmission and a target linear characteristic can be decreased by determining a command value (u) to the step motor ( ) under a control gain determined based on a time differential ({dot over (f)}) of the coefficient (f) (S ).