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:
Sep. 11, 2001
Filed:
Dec. 14, 1999
Hiromasa Sakai, Yokosuka, JP;
Motoharu Nishio, Yokohama, JP;
Nissan Motor Co., Ltd., Yokohama, JP;
Abstract
In a non-finite speed ratio transmission device using a toroidal continuously variable transmission (,), a hydraulic cylinder (,) for driving a power roller (,) via a trunnion (,), a shift control valve (,) for controlling a supply direction of oil to an oil chambers (,A,,B) of the hydraulic cylinder (,), and a precess cam (,) which feeds back a displacement of the power roller (,) to the shift control valve (,) so as to shut-off the flow of oil to and from the oil chambers (,A,,B), are provided. The shift control valve (,) comprises a drain port (,J) which can be connected to the oil chamber (,A) and a drain port (,I) which can be connected to the oil chamber (,B). By providing a positive torque control valve (,) which controls the oil pressure of the drain port (,I), and a negative torque control valve (,) which controls the oil pressure of the drain port (,J), the shift control valve (,) controls a differential pressure &Dgr;P of the oil chambers (,A,,B) from,to a line pressure PL when the speed ratio ic of the toroidal continuously variable transmission (,) is maintained in the vicinity of a geared neutral position GNP.