平面图形中直线段的尺寸分析

Analysis of linear curves in dimensioning of two-dimensioned graphics

大多数教材中对平面图形的尺寸分析比较简单、一致,而近几年出版的一部分新教材提出了图形分解与特征形状的概念。在平面图形中,直线段的尺寸标注取决于它是哪类线段,即它与其它线段之间的关系,或者说线段本身的作用决定了应该标注的尺寸。为此,分析了不同的线段需要哪些尺寸来定形和定位,以及尺寸基准、图形的对称性、国标规定对所需的定形尺寸、定位尺寸的个数及标注方式的影响。

Most of the current teaching-book describe the dimension analysis of two dimensioned graphics simply.some published recently come up with the new concepts-drawing disintegrating and symbolic graphics.In two-dimensioned graphics, how to dimension the straight line depend on its relation with other curves.This article analyses the method of dimensioning according to the function of the straight line, and which dimension the different type of the linear curves should have for location and shape.It also studies the influence of dimension datum 、symmetry graphics and the National Standard on the style and the number of the dimensions needed.