Recently, all-wheel drive technologies have been actively developing, more and more new systems are being developed that use a large number of parameters that analyze the situation and help the driver in driving. One such solution is the Haldex clutch or all-wheel drive clutch.
This coupling cannot be called an advanced solution; the coupling has already had 5 generations, starting in 1998, each of which has its own innovations. In this material we will consider all generations of couplings, the principle of operation, their design, advantages and disadvantages.
Haldex coupling 1st generation
The first generation was first installed on a car in 1998.
The principle of operation of the 1st generation Haldex coupling is to determine the difference in the rotation speed of the shafts of the front and rear axles.
Thus, at the moment the front axle, which is the drive, slips, the rear axle is connected.
This device caused discomfort to a large number of owners of cars equipped with a Haldex clutch. What caused the negativity? The fact is that when, for example, at the moment of turning and adding gas, the front wheels begin to slip, the rear axle is connected. It's no secret that all-wheel drive and front-wheel drive cars behave completely differently, which created discomfort in driving. When all-wheel drive is connected, controllability deteriorates and traction changes.
The coupling has 3 main components:
- hydraulic pump;
- electric pump;
- solenoid valve.
Let's take a closer look at each component separately.
The hydraulic pump performs the main function, namely locking the clutch. Oil pressure acts on the actuator cylinder, which in turn presses the clutch discs, blocking the clutch.
The electric pump helps reduce the clutch lock-up time of the hydraulic pump. This happens due to the fact that the electric pump presses the clutch discs in advance, thereby eliminating the gaps, reducing the time until complete blocking.
