This invention relates to a transfer case for four-wheel drive vehicles and more particularly to an arrangement wherein a dual planetary gear reduction unit delivers torque to its output shaft at a two-to-one ratio.
The U.S. Pat. No. 4,677,873 issued July 7, 1987 to Eastman et al. entitled Transfer Case With Inter-Axle Dual-Planetary Differential discloses a dual-planetary arrangement operative as an interaxle differential. The U.S. Pat. No. 3,060,765 issued Oct. 30, 1952 to Rinsoz discloses a differential gear including a toothed driving crown wheel rigid with the casing. A planetary gear arrangement is housed inside wherein two planet pinions mesh with sun wheels keyed to the ends of two aligned driven shaft elements.