Kristopher J Kokko

20130232962, Sep 12, 2013

Dec 17, 2012

13/717102

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

GM Global Technology Operations LLC - Detroit MI

F15B 9/00

60327

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.

20140315683, Oct 23, 2014

Apr 17, 2013

13/864307

- Detroit MI, US
KRISTOPHER J. KOKKO - NOVI MI, US
TONY T. HOANG - WARREN MI, US
BRIAN L. SPOHN - HOLLY MI, US

GM GLOBAL TECHNOLOGY OPERATIONS LLC - Detroit MI

B60W 10/02
B60W 10/06

477 86

Method to control a clutch device within a transmission selectively coupling an internal combustion engine to a driveline includes controlling slip of the clutch device in response to an engine autostart event. Controlling slip includes adjusting a commanded fill pressure to the clutch device to a first predetermined magnitude that exceeds a pressure threshold until the clutch device is filled, decreasing the commanded fill pressure from the first predetermined magnitude to a second predetermined magnitude below the pressure threshold, and adjusting the commanded fill pressure in accordance with a first ramping profile and in accordance with a subsequent second ramping profile when a transmission input speed achieves a desired first transmission input speed.

20140163845, Jun 12, 2014

Dec 12, 2012

13/712148

- 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

GM GLOBAL TECHNOLOGY OPERATIONS LLC - Detroit MI

F02D 29/02

701112

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.