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Equalization valve for rear wheels

Equalization valve for rear wheels


In order to control both rear wheels with only one solenoid valve, a pressure- controlled equalization valve for the rear wheel circuit is added to the solenoid valve.

The equalization valve ensures that the same brake pressure is applied to both rear wheels during ABS activation . This gives the car good directional stability.

During ordinary braking with no ABS activation, brakepressure goes to the RH rear wheel through the solenoid valve (normal position) and brake pressure to the LH rear wheel through the equalization valve.

This gives us ordinary dual-circuit braking - one circuit for the RH front wheel and LH rear wheel and the other circuit for the LH front wheel and RH rear wheel.

On ABS activation of the rear wheels the solenoid valve assumes the pressure holding position. The passage to the RH rear wheel is now blocked. If the pressure from the master cylinder rises, there will be a pressure difference above and below the piston (1). The piston rises and the valve (2) closes the pressure to the LH rear wheel.

If the pressure to the RH rear wheel drops (pressure relieved), there will be a bigger pressure difference above and below the piston (1) which will rise further until the pressure for the RH and LH rear wheels has achieved equilibrium.