EXPERIMENTAL VERIFICATION OF NUMERICAL TEST RESULTS FOR A DOUBLE MULTI- LEAF SPRING

A double spring used in the vehicle suspension, as a combination of spring elements of characteristics close to linear ones, actually provides non-linear suspension characteristics. Due to requirements for the truck suspension being designed, the spring characteristics in the whole range of load changes should meet the vehicle motion smoothness related to keeping the frequency of own suspension vibrations within a range of 1-2 Hz [8, 10]. A prototype double spring made of a four-leaf main spring and two- leaf auxiliary spring (Fig. 1) makes a subject of considerations. Characteristic features of that structural solution includes a clearance between the main spring and the auxiliary spring. This work presents the results of numerical tests for three models of MES double spring [23] that were compared with experimental test results. An evaluation of usability of individual numerical models was made for representation of a double spring characteristics, contact between individual leaves and regular stress in the main leaf (the so-called safety leaf). The smallest differences between the stress results obtained from numerical tests compared to the laboratory tests, for the beam and shell models, have been obtained only for one extreme main (longest) leaf.