工程制图第6章简化与规定画法

Simplified Representation 简化画法Conventional Representation规定画法Exercises 练习题Simplified and Conventional Representation 简化画法与规定画法请点击相应标题显示其内容60°6 teeth1.If a part obtains some same features （such as gear, slot etc.) which are distributed according to certain rules, it is only needs to draw several whole features and use center line to indicate their center position and label the total number in the part drawing.当多个相同结构（孔、槽、齿等）按规律分布时,只需画出一个或几个完整的结构,其余用细实线连接或用细点划线标明中心位置,并注明总数。

请点击鼠标左键显示后面内容9 slots6 holes 20 teeth英国图例2.Long parts (such as shaft, pole and so on) varying profiled bar length by length by a certain rule can be shorten to represent The conventional representation of breaks is used to shorten.较长的机件（轴、杆等）沿长度方向的形状一致或按一定的规律变化时，可断开后缩短绘制，断裂处用波浪线表示,其尺寸仍按实长标注。

请点击鼠标左键显示后面内容断开后只画其两端Staff棱柱形长杆Shaft 圆柱形长轴Tube 圆柱形长管Sign trim size Sign trim size Sign trim size 断开后斜度度应一致。

断开后斜度应一致英国图例4. The view of symmetrical part can be drawn a half or quarter of it, two continuous thick lines paralleling with each other should be drawn on the two ends of center lines. 在不致引起误解时，对称机件的视图可只画一半或四分之一，并在对称中心线的两端画出两条与其垂直的平行细实线。

英国图例请点击鼠标左键显示后面内容左右对称可只画半边，应在中心线两端加与其垂直的平行线符号上下左右均对称可只画1/4, 应在中心线两端加与其垂直的平行细实线符号5. Reticulation material, weaving material and diamond knurling should be indicated with continuous thick lines .网状物、编织物及机件上的滚花部分，应用粗实线完全或部分地表示出来。

Straight m0.8直纹Diamond m 0.8斜网纹请点击鼠标左键显示后面内容Cross-hatch m 0.8直网纹Knurling m0.8滚花英国图例Simplified Representation 简化画法左视图表达出前部小平面结构6.When the view cannot express plane well, plane symbol is used to indicate it .当图形不能充分表达平面时，可用平面符号（用两条细实线画出对角线）表示。

断面图表达出前部小平面结构小平面未用左视图或断面图表达，则应画出相交细实线用断面图来表达四棱锥台的平面Square (用断面图表达断面形状为正方形)该平面未采用断面图表达，则应画出相交细实线请点击鼠标左键显示后面内容英国图例B B 或（or ） B小平面未采用断面图表达，则应画出相交细实线请点击鼠标左键显示后面内容Simplified Representation 简化画法3.Partial view of symmetrical structure (such as key slot )in a part can be expressed by drawing the structure solely. Intersection of small structures on a part can be simplified or omitted on other views if it has been expressed clearly in one view.零件上对称结构(如键槽)的局部视图，可单独画出该结构的图形。

机件上较小的结构所产生的交线(相贯线)，如果已经有一个图形已表达清楚该结构，则可简化或省略。

单独画出对称结构键槽的局部视图已有图应省略英国图例已有图形表达该键槽则可省略相贯线形表达该圆孔则省略相贯线7.It is permitted to omit cutting symbols when it would not be mistaken, but the labeling of the cutting positions and cuts shall obey the rules. Small fillets or 45°chamfers are permitted to omit, but they should be illuminated in engineering requirements.在不致引起误解时，零件图中的移出断面图，允许省略剖面符号，但剖切位置和断面图的标注必须遵守规定。

在不致引起误解时，零件图中的小圆角、锐边的小倒圆或45°小倒角允许省略不画，但必须注明尺寸或在技术要求中加以说明。

请点击鼠标左键显示后面内容省略小圆角省略小圆角省略倒角省略剖面符号省略剖面符号英国图例8.Structures with small pitch in a part could be drawn according to its small end if expressed in one view.If circle or arc has the included angle of 30°or less than 30°to projective plane, its projection can be expressed with a circle or arc directly.机件上斜度不大的结构，如在一个图形中已表达清楚，则在其他图形中可按小端画出。

与投影面倾斜角度30°的圆,其投影可用圆或圆弧来代替。

请点击鼠标左键显示后面内容按小端的宽度画出均按圆形画出1. Symmetrically located ribs or spokes are shown in section in revolved positions to show the ribs true size. Rib’s or spokes are not section-lined in section.对于机件的肋、轮辐及薄壁等，如按纵向剖切，这些结构都不画剖面符号，而用粗实线将它与其邻接部分分开。

Rib肋板不画剖面符号Cutting plane剖切面位置Cutting plane 剖切面位置请点击鼠标左键显示后面内容Conventional Representation 规定画法英国图例Rib 肋板不画剖面符号2. A part with symmetrically located ribs, spokes and holes are shown in section with those symmetrically features rotated to the cutting plane.当机件回转体上均匀分布的肋、轮辐、孔等结构不处于剖切面上时，应将这些结构旋转到剖切面上画出。

将肋板转到剖切面位置后再画出将孔转到剖切面位置再画出请点击鼠标左键显示后面内容Conventional Representation 规定画法英国图例置再画出将孔转到剖切面位Exercises练习题1.Analysis and find out the mistakes from sectionalviews and correct the front view.分析并找出剖视图中的错误，画出正确主视图。

2. Sketch full sectional views for each drawing.画出下列各立体的全剖视图。

请点击题目显示其内容本章结束谢谢您的认真学习！退出前一页1 .Analysis and find out the mistakes from sectional views and correct the front view.分析并找出剖视图中的错误，画出正确主视图。

肋按纵向剖切时不画剖面线画出。

画出。

画出。

回转体上均匀分布的肋和孔不在剖切面上时，应旋转到剖切面画出。

请点击击解答显示其内容(1)(2)2. Sketch full sectional views for each drawing.画出全剖主视图。

(1)(2)请点击解答显示其内容Incorrect Correct请点击鼠标左键显示后面内容画剖面线。

If the cutting plane passes crosswise through a rib or web, spoke,thin wall,etc. the member should be section-lined.若沿横向剖切肋板、轮辐、薄壁等结构时应画剖面线。

英国标准BS 308 有关规定上、。

衬套剖面线与支架的剖面线应有区别半剖并省略剖面线纵向剖时肋板处不画剖面线Conventional Representation 规定画法Simplified Representation简化画法Simplified Representation简化画法Simplified Representation简化画法Simplified Representation简化画法Simplified Representation简化画法省略相贯线键槽与轴相贯线Simplified Representation简化画法省略剖面线为方便注尺寸需画虚线Conventional Representation规定画法Conventional Representation 规定画法BS 308 states that the following are NOT sectioned even if they are ‘cut’ longitudinally.英国标准BS308规定:当沿纵向剖切下列机件时,均按不剖画。