簧下质量

而在地铁动车中，牵引电机采用架悬的悬挂方式，减小一系簧下质量，可降低轮轨动作用力，改善车辆的曲线通过性能。

So in the metro , traction motor adopts suspension mode , reducing the unsprung mass , can reduce the wheel-rail action force , and improve vehicle curve negotiation performance .

为了降低簧下质量，端轴轮对采用独立制动轴装置，随着簧下质量的降低，轮轨力降低不明显，但采用新悬挂参数机车，轮轨力有明显的降低。

In order to reduce unsprung mass , every end shaft adopts the independent brake shaft . With the unsprung mass getting lower , the wheel-rail force decreases not obviously , but the wheel-rail force of the locomotive with the new suspension parameters reduces obviously .

高强度铸造AL-Si合金作为高速列车转向架的箱体材料，不仅具有良好的机械性能、物理性能、切削加工性能以及铸造性能等优点，而且能有效地减轻簧下质量。

As the material for manufacturing the box body used for bogies in high-speed trains , the high strength cast Al-Si alloy not only provides good mechanical , physical and casting properties and cutting behavior , but also can effectively reduce the unspring mass .

为了获得较小的轮轨力，先应通过优化悬挂参数，在悬挂参数达到最优或者结构条件不能满足的情况下可以选择采用独立制动轴装置，来降低簧下质量，进一步降低轮轨力。

In order to get a smaller wheel-rail force , firstly , we should optimize the suspension parameters . When the suspension parameters are optimal or the structure can not meet the conditions , we can use the independent brake shaft to reduce the wheel-rail force .

根据汽车行驶平顺性和操纵稳定性的评价方法，确定簧上质量的加速度、车轮与地面间的动载荷以及簧上、簧下质量的动挠度为评价指标。

In order to evaluate the riding comfort and handling safety of automobiles , the acceleration of sprung mass , the dynamic load between wheel and road , and the dynamic deflection between sprung mass and unsprung mass are determined as the criteria used for evaluation of automobile suspension systems .