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:
Jun. 25, 2002
Filed:
Nov. 09, 2000
Nissan Motor Co., Ltd., Yokohama, JP;
Abstract
A toroidal continuously variable transmission ( ) comprises power rollers ( C, D, C, D) which transmit a torque between input disks ( A, A) and output disks ( A, B), and trunnions ( ) which drive the power rollers ( C, D, C, D) in a perpendicular direction to a rotation shaft ( A) according to a differential pressure between a first oil chamber ( ) and a second oil chamber ( ). When the second oil chamber ( ) is at higher pressure than the first oil chamber ( ), the toroidal continuously variable transmission ( ) causes a downshift, and when the first oil chamber ( ) is at higher pressure than the second oil chamber ( ), the toroidal continuously variable transmission ( ) causes an upshift. The first oil chamber ( ) is connected to a first passage ( ) and the second oil chamber ( ) is connected to a second passage ( ). A speed ratio control valve ( A) controls a direction and a flowrate of the first passage ( ) and the second passage ( ). A pressure control valve ( ) limits a maximum differential pressure of the first oil chamber ( ) and the second oil chamber ( ) when the transmission ( ) causes a downshift to be less than a maximum differential pressure of the first oil chamber ( ) and the second oil chamber ( ) when the transmission ( ) causes an upshift. This arrangement prevents a sharp downshift of the toroidal continuously variable transmission ( ) due to a fault or incorrect operation.