为探究包边过程的预折刀工作终止位置对包边边界缩进的影响规律，以某车型前门的包边过程为研究对象，基于AutoForm软件建立有限元模型，定义了预折刀相对进给量以量化表述预折刀工作终止位置，并在包边机上进行验证实验，在此基础上提出了包边边界缩进的调整流程.结果表明：随着预折刀相对进给量不断增加，包边边界缩进逐渐增大，但并非呈线性增长；当预折刀处于欠进给时，随着预折刀相对进给量的增加，包边边界缩进增量很小；当预折刀处于过进给时，利用2次函数可以拟合包边边界缩进与预折刀相对进给量的关系.
In order to study the effect of pre-hem steel stopping position on boundary roll-in, the hemming process of a front door was analyzed and modeled based on AutoForm. Relative stroke was defined to quantify the pre-hem steel stopping position. The analysis result was also verified by the experiments on the hemming machine, and a method of adjusting boundary roll-in was proposed based on the numerical and experimental analysis. The investigation shows that the boundary roll-in increases with the increase of the relative stroke, but the increasing process is non-linear. When the pre-hem steel has under stroke, the influence of the relative stroke on the boundary roll-in is relatively small. While a quadratic function fits the relation between boundary roll-in and relative stroke well when the pre-hem steel has over stroke.
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