| Abstract: | A new vertical stiffness formula, including a term incorporating the rate of change of the effective area of a belted air spring, is established. Quasi-static vertical stiffness values are calculated using the formula. And four different experimental methods are used to study static and quasi-static vertical stiffness of a belted air spring. Results calculated using the formula are consistent with the experimental data. When the reservoir is small or the load is heavy, we can precisely predict the static and quasi-static extents of vertical stiffness. Differences between theoretical and experimental results are also analysed. We study the influence of geometric parameters on vertical stiffness of a belted air spring. When a reservoir is added to decrease vertical stiffness, we show how to avoid negative stiffness. |
