US Patent:
20080172162, Jul 17, 2008
Inventors:
William J. Wegeng - Avon IN, US
Randall S. Conn - Indianapolis IN, US
Mark A. Rushing - Martinsville IN, US
Ricke D. Katko - Martinsville IN, US
Assignee:
GENERAL MOTORS CORPORATION - Detroit MI
International Classification:
G06F 17/00
Abstract:
A vehicle transmission retarder control apparatus is provided including an engine, a throttle, a brake, a transmission having an output member with an actual transmission output speed, a speed sensor operable for measuring the actual transmission output speed, a plurality of user-commandable input devices for selecting a desired transmission output speed, and a controller having an algorithm for controlling the amount of retarder request to provide a zero or constant rate of deceleration independently of weight and axle ratio. Additionally, a method is provided for controlling a transmission retarder, including measuring the actual transmission output speed, sensing a desired transmission output speed using a plurality of user-commandable input devices, communicating the actual and desired speeds to a controller, and commanding the retarder to apply a continuously variable opposing torque to the transmission based on the actual and desired output speeds to achieve a constant rate of deceleration.
