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:
Dec. 24, 1991
Filed:
Sep. 14, 1989
Kazunori Ishikawa, Toyota, JP;
Takuji Taniguchi, Okazaki, JP;
Kunihiro Iwatsuki, Aichi, JP;
Yutaka Taga, Aichi, JP;
Aisin AW Co., Ltd., both of, JP;
Toyota Jidosha Kabushiki Kaisha, both of, JP;
Abstract
A reverse-engaging condition is prevented by a reverse inhibit valve operated by the solenoid valve even if a shift lever is operated to a reverse range at forward running. A solenoid valve controlling a 1-2 shift valve is 'OFF' when controlling a manual valve to a reverse range under 7 km/h of a vehical speed. The reverse inhibit valve is at a right-half position. Therefore, the hydraulic pressure from the reverse range port of the manual valve runs through oil passages and supplied to the hydraulic servos. At forward running over 7 km/h the solenoid valve is switched 'ON', the reverse inhibit valve is switched to a left-half position and oil passages are isolated. When the solenoid valve is switched at forward running, a hydraulic pressure from a R range port of the manual valve does not operate on a difference of cross sectional areas of lands of the reverse inhibit valve, so that the reverse inhibit valve is kept at the right-half position together with a pressing force of a spring therein.