TM 9--2520--215--34
0005 00--21
THEORY OF OPERATION -- CONTINUED
0005 00
TORQUE PATHS THROUGH TRANSMISSION – Continued
Torque Path In Low Range, Converter Drive, No Steer
NOTE
Refer to Torque Path In Low Range, Converter Drive, No Steer and Action of Hydraulic
System, Low Range Converter drive No Steer.
When in low range, converter drive, no steer, the torque path is as described above, except that the low--
range clutch is engaged and the transmission of torque is extended as outlined below.
When the low range clutch is engaged, the low--range planetary ring gear is held stationary. The ring gear
becomes the reaction member of the low range gear set. The low range sun gear, being splined to the turbine shaft,
rotates. The sun gear rotates the pinion gears and in turn, the low--range carrier.
The low--range carrier is splined to the output bevel drive gear. The carrier rotates the gear, which, in turn,
rotates the output bevel--driven gear. The driven gear is splined to the output drive shaft, which in turn is splined to
the steer planetary ring gears. Both ring gears rotate.
The reaction members in the steer planetaries are the sun gears. The sun gears are stationary during
straight travel because the tendency of each to rotate is opposed by the tendency of the other to rotate in the opposite
direction. Both are prevented from rotating in the same direction by the steer tie shaft, tie shaft pinions, and tie shaft
idler. These are meshed with gears connected to the steer planetary sun gears.
The steer planetary ring gears cause the pinion gears to rotate about the stationary sun gears. The steer
planetary carrier, to which the pinions are mounted, connect to the output reduction sun gear. The output reduction
planetary ring gears are stationary at all times. Accordingly, the output reduction planetary pinions are forced to rotate
within the ring gears. The carriers are splined to the output shafts, which rotate and drive the vehicle track sprockets.
In addition to the torque multiplication ratio of the torque converter, the speed reduction ratios of the low range
planetary, output bevel gears planetaries, and output reduction gears determine the final torque and speed reduction
ratios available at the vehicle track sprocket. All of these ratios are listed in this work package.
LOW---RANGE CLUTCH APPLIED
DIRECTION OF TRAVEL
Torque Path in Low---Range, Converter Drive, No Steer---Schematic View
