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. 11, 1992
Filed:
Aug. 02, 1990
Nobuyuki Kato, Toyota, JP;
Ryoji Habuchi, Miyoshi, JP;
Kunio Morisawa, Toyota, JP;
Hiroshi Itoh, Toyota, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
A hydraulic control apparatus for a vehicle power transmission for transmitting power from an engine to a drive wheel a reversing mechanism having a reverse position established by a hydraulic actuator. The apparatus includes a reverse inhibit valve disposed in a hydraulic line leading to the hydraulic actuator and having a reverse inhibit position for inhibiting the mechanism from being placed in the reverse position and a non-inhibit position for permitting the mechanism to be placed in the reverse position. The apparatus uses a first and a second pilot pressure generating device for producing a first and a second pilot pressure, respectively. A relay valve is provided for producing a first hydraulic signal for establishing the reverse inhibit position of the reverse inhibit valve, based on one of combinations of operating states of the two pilot pressure generating devices, and a second hydraulic signal for establishing the non-inhibit position, based on the other combinations.