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:
Feb. 22, 2005
Filed:
Dec. 04, 2002
Shinichiro Joe, Kanagawa, JP;
Taketoshi Kawabe, Yokohama, JP;
Michel Mensler, Kanagawa, JP;
Nissan Motor Co., Ltd., Yokohama, JP;
Abstract
A system for enhanced ratio control in a continuously variable transmission (CVT) includes a ratio control element positionable by an actuator in response to an actuator command to establish various CVT ratios in the CVT. At least one sensor generates a train of pulses indicative of speed of rotation of a predetermined rotary member of the CVT. A measured CVT ratio generator derives information of an actual CVT ratio out of at least the train of pulses to give a measured value of CVT ratio. A filter processes the measured value of CVT ratio in a manner to refine the information of the actual CVT ratio to give an estimated value of CVT ratio. A command generator determines the actuator command such that the actuator command remains unaltered when a deviation of the estimated value of CVT ratio from a desired value of CVT ratio stays within a dead zone. A filter and command generator manager narrows the dead zone to meet precision requirement upon determination that the desired value of CVT ratio has been accomplished and adjusts filter gain at the filter in a manner to keep amplitude at frequency of noise that is contained in the measured value of CVT ratio within the narrowed dead zone.