IMPROVEMENT OF DYNAMIC WHEEL LOADS AND RIDE QUALITY OF HEAVY AGRICULTURAL TRACTORS BY SUSPENDING FRONT AXLES

This article describes the suspended front axle for heavy agricultural tractors which is currently being developed by ZF Passau, and illustrates the improvements of dynamic wheel loads and ride quality provided by this new design. Details of the ZF- axle layout and the hydro-pneumatic suspension are provided. The behaviour of a tractor with a suspended front axle when driven along an uneven roadway at 50 km/hr are provided. These show that the wheel load variations of both front and rear axles are lower than those for vehicles with normal axles. This advantage holds for any loading condition as the hydro- pneumatic suspension system automatically adjusts to different static axle loads. A simulation program, ATRACTION (Agricultural TRACTor Simulation) is used to show that this sort of front axle could be adapted for use with all tractor types. For the covering abstract of the conference see IRRD 852196.