In this paper, it is presented that the locus of a line crossedwith each of two guide lines and a guide conic not being on a commonplane is a ruled surface of fourth order.
本文提出了由一条二次曲线和与该二次曲线不共面的两条异面直线为导线，与该三导线均相交的直线轨迹是一个直纹四次曲面，并讨论了二次曲线分别为椭圆、双曲线和抛物线时，形成的曲面的形状特征。
It is presented that the locus of a line crossed with each of two guide line and a guide conic not being on a common plane is a ruled surface of fourth order.
提出了由一条二次曲线和与该二次曲线不共面的两条异面直线为导线，与该三导线均相交的直线的轨迹是一个直纹四次曲面，并对该曲面的特性作了一些初步探讨。
This paper present the geometrical properties of some typical trajectories for finitely separated positions,such as cylindrical curve,spherical curve,constant inclination ruled surface and constant distance ruled surface.
给出了有限分离位置圆柱面曲线、球面曲线、定斜直纹面及定距直纹面等几类空间轨迹的几何特征。
