On the Necessity and Approach of Marking Design Data in Drafts
论图样中标注设计基准的必要性和方法

The paper, by means of illustrations, demonstrates the necessity of marking definitely design data in drafts, because these design data are the key factors of the embodying the intentions of the designer and the functions of components and parts. In combination with what may occur in practice, the author, as well, puts forward a set of approach that can be used conveniently without complicating the drafts .The approach is used to mark directly design data symbols consisted of signs and codes on the design data elements in drafts and the solution to the of marking of the design data symbols in computer aided drawing. After marking the design data symbols(two or three the symbols only) in drafts, the draft users will know where the design data are at once. Therefore, all kinds of the problems, which arise from the design data not having been marked in drafts, will be solved entirely. Meanwhile it points out when the design data symbols are marked directly on the design data elements of components and parts in drafts, other various problems like the conflicts of many kinds of dimensional tolerances coexisting in a same draft, the disagreement between noted dimensional tolerances and unnoted dimensional tolerances in a same one will be solved effectively.