Min Kyu Kim

US Patent:

20130232962, Sep 12, 2013

Filed:

Dec 17, 2012

Appl. No.:

13/717102

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

US Classification:

60327

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.

US Patent:

20140163845, Jun 12, 2014

Filed:

Dec 12, 2012

Appl. No.:

13/712148

Inventors:

- Detroit MI, US
Zhen J. Zhang - Canton MI, US
Casie M. Bockenstette - Clarkston MI, US
Todd R. Berger - Pinckney MI, US
Kristopher J. Kokko - Novi MI, US
Min K. Kim - Troy MI, US

Assignee:

GM GLOBAL TECHNOLOGY OPERATIONS LLC - Detroit MI

International Classification:

F02D 29/02

US Classification:

701112

Abstract:

A method of preventing an automatic engine stop includes: determining a pressure difference between an accumulator fill volume and a fluid conduit in selective fluid communication with the accumulator fill volume; determining a change in the accumulator fill volume from the determined pressure difference; adding the change in the accumulator fill volume to a previous estimate of the accumulator fill volume to determine a current estimate of the accumulator fill volume; comparing the current estimate of the accumulator fill volume to a predetermined threshold; and preventing an automatic engine stop if the current estimate of the accumulator fill volume is below the predetermined threshold.