直角三角形法在制图教学中的探索与研究

An Exploration and Research on the Right Triangle Method in Teaching Mechanical Drawing

直角三角形法是制图课程中一种很重要的方法,在实际的教学过程中我们发现学生对于运用直角三角形法求解已知线段的实长的过程中,会出现形形色色的错误,或者角度标注错误,或者实长表达不清,或者坐标差取值错误。针对学生在实际运用中的这些错误,为了方便有效地记忆不同直角三角形法的应用规律,本文详细地讨论了直角三角形法具体应用特点,并用实例详解了其具体解法,可以总结为:"选投影,作直角,坐标差值为一边,连端点,定实长,倾角看差值"。

Right triangle method plays an important role in drawing course,in the actual teaching process,we found that students make various errors when using right triangle method to get the real length process of the known segment,such as,angle tagging errors,or the real length expression is unclear,or wrong coordinate difference values. In view of these errors made by students in the practical application,in order to facilitate the memorization of the effective application regularities of different right triangles,this thesis discusses in detail the application characteristics of specific right triangle and illustrates its specific solutions in detailed examples,which can be summarized as 'Options projection','Cartesian coordinates the difference is one side',even the 'end points','fixed real length','inclination to see the difference. '