相贯线上两个特殊点投影的求法

On Solution of the Two Special Point Projection on Intersection Lines

中专制图教科书中 ,对圆柱与圆锥轴线垂直相交时 ,相贯线投影作图 ,大都采用先找特殊点 ,再用辅助平面法找一般点 ,最后判断点的可见性并描点连线的方法。用数学分析法论证圆柱与圆锥轴线垂直相交时 。

In drafting textbook of secondary technical school, while cylinder intersect circular cone vertically, steps of solution of their intersection lines projection are: firstly, finding special point, secondly, finding common point by auxiliary plane, lastly, estimating visibility of point and drawing lines. This paper introduces solution of the two special points projection on intersection lines by mathematical analysis method while cylinder intersect circular cone vertically.