3. HYDRAULIC FRONT AXLE SUSPENSION 3.1 FRONT SUSPENSION CONTROL VALVE 2. When the operator activates the system When the operator presses the switch to activate the suspension, the electronic control unit energises the solenoids (1) and (5). This allows the pressurised oil from the pump (2) to flow to line b and thus start to push the piston (4) downwards. At the same time, the oil compresses the membranes of the accumulators and the oil in lines a and b increases. When the pressure in line a reaches the opening pressure of the relief valve (8), the valve opens and discharges some of the oil to the drain circuit.
When the position sensor detects that the suspension has attained the levelling position, the electronic control unit de-activates the solenoids (1) and (5) and the part of the system containing the precharged accumulators is isolated from the rest of the system. 10-35 ( 3 ( (2. -0 3(1 3(/ -/ ( -.1 -./ (.1 3.1 ,.0 3 3./ )(1 ,./ " (./ - -1 ,.1 3 ( (2. -0 3(1 3(/ -/ ( -.1 -./ (.1 3.1 ,.0 3./ )(1 ,./ " (./ -1 ,.1