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:
Nov. 12, 1991
Filed:
Dec. 17, 1990
Yoshinobu Soga, Susono, JP;
Masami Sugaya, Susono, JP;
Abstract
A hydraulic control apparatus for controlling the speed ratio of a vehicle continously variable transmission having a clutch device disposed in series with the transmission in a power transmitting line, to disconnect the power transmitting line when a shift lever is placed in a neutral position. The apparatus includes a first shift control valve for producing a first output for changing the speed ratio, based on a required output pressure corresponding to the currently required vehicle acceleration value, and a first input shaft speed corresponding to the transmission input shaft speed, a second shift control valve device for producing a second output for changing the speed ratio, based on a second input shaft speed pressure and an output shaft speed pressure corresponding to the input and output shaft speeds of the clutch device, respectively, so as to reduce a difference between the input and output shaft speeds of the reversing device, and a switching valve device for applying the first and second outputs to the transmission when the shift lever is operated to the drive and neutral positions, respectively.