【摘要】 强调了子午投影法的两个特点,即几何元素至回转轴和至水平投影面的距离都不改变。提出以这两个不变量建立直线的子午投影的方程式,也就是确定回转曲面轮廓线的方程式。以二维的平面曲线的方程式代替了三维空间曲面的方程式。文中通过方程式的推导,论证了上述观点,并以此为基础,进一步论述了各种特殊位置直线的子午投影的方程式,以及这些子午投影旋转后所形成的曲面。更多还原

【Abstract】 Based on the two Characteristies of meridian projection, i.e, the distance from geometric element to either the rotation axis or the horizontal projection plane is constant, the auther establishes the meridian projection equation for a line by using this two constants, so that the contour equation for a revolving surface can be derived. By this method, the 3-d space equation of the curved surface can be replaced by a plane equation. With this view point, all other meridian projection equations of lines in special positions, and the curved surface formed by the meridian projection after being rotated are presented.更多还原