Level control arrangement for vehicles having air springs

A level control arrangement for a vehicle with an air spring for suspending the chassis of the vehicle relative to at least one axle, the level control arrangement comprising:

• a source for supplying pressurized air;
• an air dryer connected to said air spring;
• a pneumatically-controllable directional-control valve having first and second control inputs and being switchable between a first switching position wherein said source is connected to said air spring via said air dryer and a second switching position wherein said air dryer is connected to the atmosphere thereby venting said air spring to the atmosphere;
• a chargeable line chargeable with the pressurized air from said source;
• a first control line connecting said first control input to said chargeable line;
• a second control line connecting said second control input to said chargeable line;
• a return spring for applying a force to said pneumatically-controllable directional-control valve for fixing said valve in said first switching state when the pressure in said first and second control lines is identical;
• means for connecting and disconnecting said first control line to the atmosphere whereby said pneumatically-controllable directional-control valve is switched into said second switching state when said first control line is connected to the atmosphere;
• said pneumatically-controllable directional-control valve being connected between said pressure source and said air dryer;
• said pneumatically-controllable directional-control valve connecting said source to said air dryer in said first switching position thereof and connecting the atmosphere to said air dryer in said second switching position thereof;
• and,
• said pneumatically-controllable directional-control valve being arranged in said chargeable line.