Torque Split Mechanism

STRUCTURE AND OPERATION

Torque Split Mechanism


CONTROL DIAGRAM







DESCRIPTION

- Ball ramp lever operates in the direction of main shaft axis according to rotation of actuator shaft and presses piston. Pressure is applied to each clutch and torque is transmitted.
- Shift fork operates in the direction of main shaft axis according to rotation of actuator shaft and performs engagement and disengagement to Hi-Lo sleeve and lock sleeve of main shaft. Mode is switched between 4H and 4L.
AUTO MODE
- The optimum torque distribution is electronically performed for front and rear wheels according to road conditions.
- Stable start without wheel spin is possible on slippery road conditions, such as on a snowy road.
- When road condition does not require 4WD driving, the status becomes close to rear wheel drive, which results in better fuel efficiency and provides FR-like steering characteristics.
- The vehicle cornering status is judged according to information from each sensor, and the optimum torque is distributed to front wheels for preventing tight-corner braking symptom.
NOTE:
When there is a difference of revolution speed between the front and rear wheel the shift occasionally changes to direct 4-wheel driving conditions automatically. This is not a malfunction.
4H MODE
- Torque distribution for front and rear wheels is fixed and stable start is achieved while driving on an rough, sandy or snowy road.
4L MODE
- Large traction force is obtained due to low gear. High running ability and escaping ability are achieved.
- Switching from 4H mode to 4L mode is not possible when the vehicle is running or A/T shift selector is shifted to any position other than neutral.

TORQUE DISTRIBUTION DIAGRAM












TORQUE DISTRIBUTION FLOW







OPERATION PRINCIPLE

AUTO, 4H MODE










1.Transfer control unit supplies command current to transfer motor.
2.Transfer motor operates and actuator shaft rotates clockwise.
3.Shift fork operates according to rotation of actuator shaft. Sun gear and Hi-Lo sleeve are engaged.
4.Ball ramp lever operates in axial direction via cam fixed on actuator shaft according to traction torque of transfer motor, presses piston, and thrusts multiple plate clutch.
5.Torque is transmitted to front wheels according to thrusting pressure of multiple plate clutch.
NOTE:
Torque transmitted to the front wheel is determined according to the command current.
4L MODE










1.Transfer control unit supplies command current to transfer motor.
2.Transfer motor operates and actuator shaft rotates counterclockwise.
3.Shift fork operates according to rotation of actuator shaft. Planetary carrier assembly and Hi-Lo sleeve are engaged.