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, 1996
Filed:
Oct. 31, 1995
Akihito Iwata, Hekinan, JP;
Kazumasa Tsukamoto, Toyota, JP;
Kazuhiro Mikami, Kariya, JP;
Masahiro Hayabuchi, Anjo, JP;
Yoshihisa Yamamoto, Nishio, JP;
Aisin AW Co., Ltd., , JP;
Abstract
A control system for an automatic transmission, having a fluid transmission unit for transmitting the rotation of an engine to a speed change unit. The control system includes a clutch which is applied responsive to selection of forward running range; a one-way clutch which is locked, when the clutch is applied, to establish a forward first speed; a brake for locking the one-way clutch, to block reverse rotation of the output shaft of the speed change unit. First and second hydraulic servos apply, respectively, the clutch and the brake responsive to receipt of oil pressures. A control unit controls the oil pressures fed to the first and second hydraulic servos. The control unit starts the feed of oil pressure to the second hydraulic servo responsive to selection of a forward running range, provided the vehicle is substantially stopped, the engine is idling and the foot brake is engaged. The control unit starts the reduction of the pressure of the first hydraulic servo upon expiration of a set time period and starts transition of the clutch from the applied state to the slipping state of the clutch upon completion of the piston stroke of the second hydraulic servo which applies the brake.