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:
Mar. 08, 1988
Filed:
Aug. 08, 1986
Hidehiko Mishima, Hiroshima, JP;
Toru Kawano, Hiroshima, JP;
Mazda Motor Corporation, , JP;
Abstract
An automatic transmission has a transmission gear mechanism for transmitting the engine output power by way of a plurality of power transmission paths, and friction engagement elements which are operated by a line pressure to change the power transmission path through the transmission gear mechanism to shift the gears. A hydraulic control system for the automatic transmission comprises a manual shift valve for changing the driving range, a plurality of shift valves each for effecting gear-shifting assigned thereto by controlling the feed of the line pressure to the friction engagement elements corresponding to the gear-shifting according to a throttle pressure and a governor pressure, and a range control valve which is provided in one of the hydraulic lines for transmitting the throttle pressure and the governor pressure to one of the shift valves to control transmission of the corresponding pressure to the shift valve according to the driving range determined by the manual shift valve, thereby changing the shift pattern according to the driving range.