Playing off-road vehicles usually cannot avoid a topic:
How many locks does this car have?
The “lock” mentioned here is not a door lock.
It’s a differential lock.
It can be said that without it, there is no way to play off-road.
The number of differential locks is an important criterion for judging off-road capability.
For example, urban SUVs usually only have an electronic differential lock.
The real off-road vehicle has two differential locks on the front axle and the rear axle,
The most advanced off-road vehicles have three locks.
In addition to the differential locks on the front and rear axles,
There’s also a center differential lock.
What is a differential?
When the car is turning,
The turning radius of the outer wheel is greater than that of the inner wheel.
This requires that the outer wheel rotates faster than the inner wheel when turning.
If the left and right wheels are directly connected,
The wheels must appear to be rolling and sliding.
will accelerate tire wear,
Increase the power consumption of the car.
The role of the differential is to:
It meets the requirements of different wheel speeds on both sides encountered by the car during driving.
Since the differential allows the wheels to turn at different speeds,
So on muddy roads, when one wheel spins,
The power will be all consumed on the spinning wheels spinning fast,
This caused the other wheels to lose power and the car was completely stuck and unable to move.
In order to avoid such a situation where the differential is not helpful when the vehicle is on a bad road,
Smart humans invented the differential lock again.
The principle of differential lock
Differential lock can be used when the wheels lose adhesion,
Weaken or disable the differential,
distribute power evenly to the wheels,
to help the vehicle get out of trouble.
The common differential locks are jaw-type,
and multi-disc clutch type,
The control methods include manual operation,
There are three types of torque sensing control and electro-hydraulic control.
The role of the three locks
The first: the central differential lock.
The off-road section will give priority to unlocking the middle lock,
The front and rear axles can be rotated at the same speed,
In the event of single wheel slip,
The center differential lock works.
The central differential lock only works when slightly off-road,
If it’s a cross axis or a shell crater,
Then it’s useless,
It can be said that the role of the central differential lock is not particularly large.
The second: rear axle differential lock.
This is the soul of a buggy,
The middle lock and the rear lock are opened at the same time,
It is to make your rear two wheels and the front axle rotate at the same speed.
If only one of your rear wheels is gripping the ground,
Then in this case,
The role of the rear axle differential lock is revealed.
For example, the cross axis or shell crater mentioned above,
Even with one wheel hanging in the air,
There’s still enough power to get the car going.
The third: front axle differential lock.
The middle lock, rear lock and front lock are opened at the same time,
All the tires of the car can get the same power,
If your car is completely suspended on one side,
Then the role of the front axle differential lock is reflected.
The opening sequence of the differential lock is:
Open the middle lock first,
If it doesn’t work, add a rear lock to the middle lock.
Finally, the three locks are opened together.
The three differential locks,
Formed a powerful off-road vehicle,
In fact, for us ordinary off-roaders,
Having center and rear differential locks is generally sufficient.
Content source: Che Youfaner, pictures from the Internet.