| 摘要 |
TRANSFER CASE The transfer case comprises differential gearing in the form of a single planetary gear set having an annulus, a first set of planet gears in engagement with the annulus, a second set of planet gears in engagement with corresponding planet gears of the first set and a sun gear in engagement with the planet gears of the second set. The input torque supplied by a transmission output member is applied to the annulus so that substantially any portion of the torque can be applied to the sun gear by appropriate sizing of the sun gear with respect to the size of the annulus. In one form of the invention, a planet carrier, upon which the planet gears are rotatably mounted, is connected to one output shaft for rotation therewith and a selectively engageable clutch permits actuation of the transfer case in a two-wheel drive mode, a full-time four-wheel drive with differential action between the front axle drive and the rear axle drive, and a four-wheel drive lock mode in which the second output shaft rotates with the first output shaft. In another form of the invention, a viscous clutch automatically drags the second output shaft for rotation with the first output shaft when the differential torque applied to one of the output shafts exceeds the traction torque load at the wheels driven by that output shaft, and thereby provides a fully automatic, full time, four-wheel drive. |
