Power Train

A: CONSTRUCTION





The gear train consists of two sets of planetary gears, three sets of multi-plate clutches, two sets of multi-plate brakes and one set of one-way clutch.





B: OPERATION TABLE

C: N RANGE








Since the rear sun gear and the high clutch drum are in mesh with the input shaft, they rotate together with input shaft.
The high clutch drum does not transmit the rotation torque to the planetary unit since the reverse clutch and the high clutch are in the free state.
The rotation torque of the rear sun gear is transmitted to the rear internal gear through the pinion gear.
However, the rotation torque of the rear sun gear is not transmitted to the rear planetary carrier since the rear internal gear idles because of disengaged low clutch. Accordingly, the rotation torque of the input shaft is not transmitted to the reduction drive shaft.

D: P RANGE








All controls do not operate, just as in the N range. The parking pawl locks the power train by pawling the parking gear which is integrated with the reduction drive gear.

E: FIRST SPEED OF D OR 3 RANGE (D1, 31)








At 1st speed of these ranges, only the low clutch is in engagement. The rear internal gear which rotates idly in P and N ranges tries to rotate counterclockwise due to engaged low clutch. However, this is blocked by the one-way clutch and secured to the transmission case.
Therefore, the rotation of the rear sun gear is converted to the revolution of the pinion gears around the sun gear, causing the planetary carrier to rotate. In this way, the rotation of the input shaft is transmitted to the reduction drive shaft after subjected to speed reduction by the planetary gear. On the other hand, the rear internal gear rotates clockwise if the reverse driving force is applied from the reduction drive shaft during coasting. This rotation frees the one-way clutch. Accordingly, since the connection between the reduction drive shaft and the input shaft is lost, the engine braking effect is not available.

F: SECOND SPEED OF D, 3 OR 2 RANGE (D2,32, 22)








At 2nd speed, the 2-4 brake as well as the low clutch is in engagement. In addition to the elements operating at 1st speed, the front sun gear which idles at 1st speed is connected to the transmission case because of engaged 2-4 brake. In this state, the rotation torque of the rear sun gear is transmitted to the rear internal gear through the front internal gear, front pinion gears, low clutch drum and low clutch. At this time, the one-way clutch is free since the low clutch drum rotates clockwise. For this reason, the rotation speed is higher than that at 1st gear by an amount of rear internal gear rotation speed.
At 2nd speed, the driving power is transmitted without being affected by the one-way clutch, Therefore, the back driving force from the reduction drive shaft is transmitted to the input shaft, thus the engine braking effect being available.

G: THIRD SPEED OF D OR 3 RANGE (D3, 33)








At 3rd speed, the low clutch and the high clutch are thrown into engagement. With the high clutch engaged, the high clutch drum rotates, which is turn rotates the rear internal gear through the front planetary carrier, low clutch drum and low clutch. This means that the rear sun gear and the rear internal gear rotates at the same speed. That is, the rear pinion gears stop rotation on its axis and resolve around the sun gear as a planetary assembly,
As a result, the input shaft and the reduction drive shaft rotate at the same speed.
The one-way clutch is released because the low clutch rotates clockwise. Since the driving power is transmitted without being affected by the one-way clutch, the back driving force from the reduction drive shaft is transmitted to the input shaft, thus the engine braking effect being available.

H: FOURTH SPEED OF D RANGE (D4)








At 4th speed, the high clutch and the 2-4 brake are thrown into engagement, The engaged high clutch causes the front planetary carrier to rotate. The engaged 2-4 brake causes the front sun gear which idles at 3rd speed to be locked.
The front planetary carrier rotates at the same speed as the input shaft. The rotation of the front planetary carrier causes the front pinion gears to revolve around the stationary front sun gear, which causes the front internal gear to rotate faster than the input shaft.
As a result, the reduction drive shaft is driven at a higher speed than the input shaft.
The one-way clutch is free because the low clutch rotates clockwise. Since the driving power is transmitted without being affected by the one-way clutch, the back driving force from the reduction drive shaft is transmitted to the input shaft, thus the engine braking effect being available.

I: FIRST SPEED OF 1 RANGE








At 1st speed of this range, the low clutch and the low & reverse brake are thrown into engagement. The 1st speed in this range shows the same operation as the 1st speed in the D or 3 range. However, the one-way clutch produces no effect because the low & reverse brake is operated.
The rear internal gear is always interlocked with the transmission case by the engaged low & reverse brake.
During coasting , therefore, the back driving force from the reduction drive gear is transmitted to the input shaft. This means, unlike the 1st speed in D or 3 range, that the engine braking effect is available in this range.

J: R RANGE








In "R" range, the reverse clutch and the low & reverse brake are thrown into engagement. The engaged reverse clutch allows the front sun gear to rotate, while the engaged low & reverse brake allows the low clutch drum to be interlocked with the transmission case.
The rotation of the input shaft causes the front sun gear to rotate, which in turn causes the front pinion gears to rotate in the reverse direction. Thus, the rotation torque of the input shaft is transmitted to the front internal gear,
At this time, the rotation speed transmitted to the front internal gear is reduced by the front sun gear and the front pinion gears,
The one-way clutch produces no effect because the low & reverse brake is in engagement.
In this range, since the power transmission is made without influence of the one-way clutch, the back driving force from the reduction drive shaft is transmitted to the input shaft, thus the braking effect of the engine being available.