Patent ID: 6354977
Filing Date: 2002-03-12
Classification: B60K

Abstract:
A power transfer system for use in a four-wheel drive vehicle having a power source and first and second drivelines, comprising:a transfer case having an input shaft receiving drive torque from the power source; a first output shaft connected to the first driveline; a second output shaft connected to the second driveline; a gearset having a first gear being a sun gear driven by said input shaft, a second gear being a ring gear, and a third gear being a pinion gear rotatably mounted on a carrier and which is meshed with said first and second gears; an interaxle differential having an input being driven by said carrier, a second ring gear fixed to said carrier, a first output being a second sun gear driving said first output shaft, and a second output being a second carrier driving a transfer mechanism coupled to said second output shaft; a range clutch assembly including a first clutch disposed between a stationary member and said second gear, a second clutch disposed between said input shaft and said carrier, and a range actuator operable in a first position to release said first clutch and lock said second clutch and further operable in a second position to lock said first clutch and release said second clutch, and a mode clutch assembly including a third clutch disposed between said differential input and said transfer mechanism and a mode actuator operable in a first position to release said third clutch and further operable in a second position to lock said third clutch; sensors for detecting operational characteristics of the vehicle and generating sensor signals in response thereto; a mode select mechanism permitting selection of an adaptive four-wheel high-range drive mode and a locked four-wheel low-range drive mode, said mode select mechanism generating a mode signal indicative of the particular drive mode selected; and a control system for moving said range and mode actuators in response to said sensor and mode signals, said control system is operable for moving said range actuator to its first position and modulating the position of said mode actuator between its first and second position as a function of said sensor signals when said adaptive four-wheel high-range drive mode is selected and said control system operable for moving said range actuator to its second position and said mode actuator to its second position when said locked four-wheel low-range drive mode is selected.