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:
Oct. 03, 1989
Filed:
Sep. 29, 1987
Hiromi Hasegawa, Oobu, JP;
Toshiaki Ishiguro, Nagoya, JP;
Aisin Seiki Kabushiki Kaisha, Kariya City, JP;
Abstract
A hydraulic control circuit for an automatic transmission is provided in which the automatic transmission has at least five forward gear shift stages. A plurality of solenoid valves are connected to hydraulic shift valves for controlling hydraulic line pressure utilized in the shifting between the various gear shift stages. Further, each of the gear shift stages is established dependent upon the operating condition of each of the solenoid valves. An inhibitor valve is provided which is operative by one of the solenoid valves and serves to provide an inhibiting function for solenoid valve disconnection and for manual downshift operation.