US Patent:
20130232962, Sep 12, 2013
Inventors:
Casie M. Bockenstette - Clarkston MI, US
Paul G. Otanez - Troy MI, US
Zhen J. Zhang - Canton MI, US
Min K. Kim - Troy MI, US
Kristopher J. Kokko - Novi MI, US
Assignee:
GM Global Technology Operations LLC - Detroit MI
International Classification:
F15B 9/00
Abstract:
A hydraulic control system and method for controlling a hydraulic system of a vehicle powertrain is provided, which includes an accumulator arranged to accumulate fluid when an engine is turned on, to retain fluid when the engine is turned off, and to discharge fluid to the transmission when the engine is restarted. The accumulator is actively filled through a controlled valve, and it may also be filled passively, for example, via ball check-valve. The method of controlling the hydraulic system includes providing a fluid line pressure to the transmission by opening a fluid passage when the engine is turned on; opening a valve to actively accumulate fluid from the fluid line pressure into an accumulator; closing the valve to retain the fluid in the accumulator; and discharging the fluid from the accumulator to the fluid passage when the engine is restarted.