The differential of a vehicle makes it possible to compensate for any differences in speed of rotation between the different wheels of the vehicle, particularly in turns. The limited-slip self-locking differential is more effective than a conventional differential on particular terrain: roads, winter conditions.
Self-locking differential with limited slip
- Limited-slip self-locking differential: what is it?
- Limited Slip Differential Decals
- Limited-slip differential maintenance
- Equipped with a limited-slip differential
Limited slip self-locking differential: what is it?
What is a differential?
When a vehicle is driving in a straight line, the two-wheel-drive rotates at the same speed. But in a turn, the inner wheel travels less distance than the outer wheel. However, if the engine transmits the same speed of rotation to the wheels, the inner wheel will skate, and on hard ground, the gear mechanisms will be put to a severe test.
The differential is there to correct this defect: if the average speed of the two wheels will always be equal to that transmitted by the engine, in turn, the speed of the inner wheel will be lower than that of the outer wheel.
The interest of limited-slip differential
The fault of the differential appears in case of stagnation of the vehicle: it is enough that a wheel is in a loose ground so that the vehicle skates. Indeed, the rotational force will completely refer to the wheel that does not oppose resistance to the detriment of the wheel on the hard which will have zero speed.
While most passenger vehicles are equipped with conventional differentials, some driven on the road or in winter conditions (ice, snow, mountain), are equipped with a limited-slip differential, which partly eliminates the risk of stagnation. .
This system makes it possible, from a given speed difference between the two wheels, to transfer the rotational force towards the most adherent wheel. It goes into action for a minimum torque of 30% (production vehicles) to 80% (competition vehicles).
Limited Slip Differential Decals
Clutch limited slip differential
From a predefined value, the difference in wheel speeds compresses a multi-plate clutch which then secures the two wheel shafts.
Visco-coupler limited slip differential
The clutch works by a hydraulic principle that can be found in the clutches on automatic cars (torque converter).
Two impellers each fixed on the shafts of wheels are rotating; when the rotation difference becomes too great (case of a wheel that skates), oil located between them creates a hydro-kinetic force that will couple them and block the differential.
This differential uses the principle of the worm and its irreversibility: the drive is only possible in the direction of drive pinion, which makes it impossible to differential rotation of the shafts.
A variant often proposed by manufacturers is a traction aid through the anti-lock electronic wheel: when the system detects an abnormal wheel rotation speed, it acts on the braking of the wheels to limit this effect.
In no case, these systems have the effectiveness of a true limited-slip differential.