摘要 |
The inventive device controls the trailing axle of a vehicle having at least two rear axles, wherein at least one rear axle is a driving axle. Pressure fluid chambers, mounted on both the driving and trailing axles, support the vehicle structure. Their pressure is varied to raise or lower the vehicle structure depending on the vehicle load and road conditions. The inventive device further comprises a first valve arrangement and a second valve arrangement. The first valve arrangement selectively connects the pressure fluid chambers of the driving axle to a compressed-air supply, to a pressure fluid sink, or isolates them. The first valve arrangement has a first and a second valve. The first valve is a 3/2-position valve actuated by a first solenoid. The second valve of the first valve arrangement is a 2/2-position valve actuated by a second solenoid. The second valve arrangement is a 3-position valve actuated by a third solenoid. The 3-position valve is controlled by cooperation of the third solenoid and a control pressure. This selectively connects the pressure fluid chambers of the trailing axle to the pressure fluid chamber of the driving axle, or to the pressure fluid sink. Alternatively, the 3-position valve isolates the trailing axle pressure fluid chambers. The control pressure is taken from the pressure fluid output of the first valve.
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