TM 5-2410-241-23-1
0009
PRIMARY POWERTRAIN CONTINUED
Torque Divider
0009
The torque divider is a unit of a planetary gear set and a torque converter turbine.
The torque divider connects the engine to the planetary transmission both hydraulically and mechanically. The
hydraulic connection is through the torque converter turbine. The mechanical connection is through a planetary
gear set.
The torque converter uses oil from the torque converter charging section of the pump to multiply the torque to the
transmission. When the machine works against a low load, the torque multiplication is low. When the machine
works against a high load, the torque multiplication is higher. A higher torque can then be sent to the transmission
during high load conditions.
The planetary gear set multiplies the torque from the engine by increasing the mechanical advantage through the
gears as the load on the machine increases.
During no-load conditions, neither the torque converter nor the planetary gears can multiply the torque from the
engine.
The torque divider and housing is installed onto the engine flywheel (Figure 8, Item 1) and housing. The output
shaft (Figure 8, Item 8) is connected to the yoke (Figure 8, Item 7), which is connected to the planetary
transmission through a drive shaft. The main components of the planetary gear set are the sun gear (Figure 8,
Item 12), planetary carrier (Figure 8, Item 14), planetary gears (Figure 8, Item 13), and ring gear (Figure 8, Item 2).
The sun gear (Figure 8, Item 12) is connected to the flywheel by splines.
The planetary gears (Figure 8, Item 13) are mounted on the planetary carrier (Figure 8, Item 14). They engage the
sun gear (Figure 8, Item 12) and the ring gear (Figure 8, Item 2).
The main components of the torque converter are the housing (Figure 8, Item 3), impeller (Figure 8, Item 4), turbine
(Figure 8, Item 11), and stator (Figure 8, Item 10).
The housing (Figure 8, Item 3) is connected to flywheel (Figure 8, Item 1) by splines. The Impeller (Figure 8,
Item 4) is connected to the housing (Figure 8, Item 3). The turbine (Figure 8, Item 11) is connected to the ring gear
(Figure 8, Item 2) by splines. The stator (Figure 8, Item 10) is connected to the carrier (Figure 8, Item 6) and cannot
turn.
Torque Converter Operation
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Oil for the operation of the torque converter flows through the inlet passage (Figure 8, Item 5) in the carrier
(Figure 8, Item 6) to the impeller (Figure 8, Item 4). The rotation of the impeller gives force to the oil and sends the
oil toward the outside of the impeller, around the inside of the housing (Figure 8, Item 3) to the turbine (Figure 8,
Item 11).
The force of the oil against the blades of the turbine turns the turbine. The turbine is connected to the ring gear
(Figure 8, Item 2), so that torque is sent to the planetary gears (Figure 8, Item 13). The torque that is sent to the
turbine by the force of the oil from the impeller cannot be more than the torque output of the engine to the impeller.
The oil that is flowing from the turbine moves in a direction that is opposite to the rotation of the impeller (Figure 8,
Item 4). The stator (Figure 8, Item 10) changes the direction of the oil. The stator is connected to the carrier
(Figure 8, Item 6) and cannot turn. Therefore, most of the oil is sent back to the impeller (Figure 8, Item 4). The
remainder of the oil flows from the stator, through the outlet passage (Figure 8, Item 9) to the oil cooler.
The force of the oil from the stator can now add to the torque output from the engine to the impeller. The extra force
adds to the torque output of the engine to the turbine. The force of the oil that is coming from the stator is
determined by the difference in speed between the turbine and the impeller. The amount of force of the oil
increases as the difference in the speed of the two components increases.
The load on the machine changes the speed of the turbine. When the load is higher, the difference in speed
between the turbine and the impeller increases. The different loads on the machine control the amount of torque
multiplication that can be added by the force of the oil from the stator.
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