Choosing Views of Detail Drawings(零件图的视图选择)

Before drawing a part, one should choose a suitable front view and other views, taking into account the function, installation site and machining methods of the part.

画零件图时,要通过对零件在机器中的作用、安装位置、加工方法的了解以及对其进行形体分析和结构分析,合理地选择主视图和其他视图。

 Choosingthe front view (选择主视图)

The following two factors should be considered when selecting the front view:

选择主视图时,主要考虑以下两点:

1. Form features

The front view should reflect the main shapes and relative positions among parts as much as possible. The front view of the pump cover in Fig. 8-1 thoroughly reflects the structures and relative positions of the various holes.

1.形状特征

主视图要较多地反映出零件各部分的形状和它们之间的相对位置。如图8-1所示,泵盖零件图中的主视图就较好地表达了各种不同结构的孔及其相对位置关系。

2. Installationposition

It refers to machining or working position. In order to enhance comprehension for production, the front view of the transmission shaft, hand wheel and other parts should be placed in accordance with their machining positions. The front view of the various boxes, pumps, valves and base parts should be placed in accordance with their working positions (as shown in Fig.8-1), although they are machined using different devices and their machining positions are not the same.

2.安放位置

安放位置即零件的加工位置或工作位置。为使生产时便于看图,传动轴、手轮、盘状等零件的主视图按其加工时的位置摆放。各种箱体、泵体、阀体及机座等零件,需在不同的机床上加工,其加工位置亦不相同,故主视图按零件工作时的位置安放。如图8-1所示泵盖零件图中的主视图,即为其工作位置。

Choosing other views (选择其他视图 )

Sections not clearly conveyed in the front view should be shown in other views. Chosen views should convey key features and avoid repetition. In short, views are selected with clear objectives. They should clearly depict the part, and provide as much information as possible. Use an adequate number of views to enhance comprehension.

主视图中没有表达清楚的部分,要用其他视图表示。所选视图应有其重点表达内容,并尽量避免重复。总之,选择视图要目的明确,重点突出,使所选视图表达方案完整、清晰,数目恰当,做到看图方便,作图简便。