Patent ID: 6152848
Filing Date: 2000-11-28
Classification: B60K

Abstract:
A transfer case for use in a four-wheel drive vehicle having a power source and front and rear drivelines, comprising:a housing;an input shaft rotatably supported by said housing and driven by the power source;a front output shaft rotatably supported by said housing and connected to the front driveline;a rear output shaft rotatably supported in said housing and connected to the rear driveline;a planetary gear assembly interconnecting said input shaft to said front and rear output shafts for delivering drive torque from the power source to the front and rear drivelines while permitting speed differentiation therebetween, said planetary gear assembly including first and second planetary gearsets having a common carrier assembly, said first planetary gearset including a first sun gear, a ring gear, and a first planet gear rotatably supported by said carrier assembly and meshed with said first sun gear and said ring gear, said second planetary gearset including a second sun gear coupled for rotation with said rear output shaft, a third sun gear coupled for rotation with said front output shaft, a second planet gear rotatably supported by said carrier assembly and meshed with said second sun gear, and a third planet gear rotatably supported by said carrier assembly and meshed with said third sun gear and said second planet gear; anda clutch for selectively coupling said ring gear to said first sun gear for driving said carrier assembly at a first speed ratio relative to said input shaft for establishing a full-time four-wheel high-range drive mode, and said clutch is further operable for selectively coupling said ring gear to said housing for driving said carrier assembly at a second speed ratio relative to said input shaft for establishing a fulltime four-wheel low-range drive mode.