Patent ID: 6098967
Filing Date: 2000-08-08
Classification: B60G,F15B

Abstract:
A level control arrangement for vehicles having an air spring for suspending the vehicle chassis relative to at least one vehicle axle, the level control arrangement comprising:a pressure source for generating pressurized air;an air drier for removing moisture from the air;a check valve connecting said air drier to said air spring so as to allow pressurized air to flow to said air spring from said air drier;a first controllable directional valve switchable between a first position wherein said first controllable directional valve connects said air spring to the atmosphere via said air drier and a second position wherein the connection to the atmosphere is blocked;a second controllable directional valve having a control input and being connected between said pressure source and said air drier;a control line for connecting said control input to said pressure source;said second controllable directional valve being a pneumatically controllable valve and being switchable between a first position wherein atmospheric air pressure is applied to said input and said second controllable directional valve connects said air drier to the atmosphere and a second position wherein pressurized air is supplied to said input and said second controllable directional valve connects said pressure source to said air drier whereby pressurized air flows through said second controllable valve to said air drier;a third controllable directional valve switchable between a first position wherein said control line is disconnected from the atmosphere and a second position wherein said control line is connected to the atmosphere;a control apparatus operatively connected to said pressure source and said first and third controllable directional valves; and,said second controllable directional valve being operatively connected to said pressure source.