System Description: Outline
The rear differential has a real-time 4WD control mechanism that enables 4WD by transmitting appropriate driving force from the front wheels to the rear wheels when necessary. It uses a real-time 4WD dual pump system (DPS) with a light and compact cam mechanism, and integrates the drive control system to the rear differential.
Equipped with a cam mechanism, this DPS real-time 4WD detects the speed difference between the front and the rear wheels. When speed difference is small, the one-way cam works to minimize the possibility of the pump to produce hydraulic pressure.
When the speed difference is large, hydraulic pressure develops in the two pumps. By controlling the engagement of the main clutch, the driving force transmitted to the rear wheels is optimized according to the driving conditions. By using a limiter switch to prevent transmission of excessive torque to the rear wheels, the propeller shaft and differential unit can be lightweight and compact. For the differential fluid, DPF II (dual pump fluid II) is exclusively used.