基本知识与技能

尺寸符号 尺寸数 字不允许 任何图线 所通过
尺寸数字
dimension figure
尺寸线
dimension line
尺寸界线
size borderline
SR8
R10
Biblioteka Baidu
Ø36
15 55
R10
20 44 箭头应与尺 寸界线接触 尺寸线与尺 寸界线应避 免相交 尺寸线不能与 轮廓线重合
字号Typeface ：20、14、10、7、5、3.5、2.5、1.8
1.汉字应写成长仿宋体，并应采用国家正式公布推行的简化 字。汉字的高度不应小于3.5mm。 The Chinese must written in long imitation song-dynasty, and must use the simplified character which published and popularized by state. The length of Chinese must not less than 3.5mm. 2.字母和数字分为A型和B型两种。在一张图上只能采用同一 种字体。 Both letter and number have two types include A and B.But there were only one type on a drawing. 3.图样上的字母和数字可写成斜体和直体。斜体字的字头向 右倾斜，与水平基准成75°。 The letter and number on the drawing could be written in italic and lifting.The heading of italic must list to starboard and the horizontal reference was 75°.
4.轴线和对称中心线应超出 4. While drawing the axis string, center 轮廓3～5mm 5.图形较小时，可用细实线 5.If the graphic was too small, the fine 代替细点画线和细双点画线
solid string could substitute stipple string and two-stipple string.
Lifting 直体
A Font A型字体
四、图线Drawing string （GB/T 17450－1998， GB/T 4457.4－2002 ） 粗实线 Heavy solid line 细实线Fine solid line 细虚线Fine dotted line 细点画线Fine stipple line
波浪线Cutting plane line
细双点画线 Fine two-stipple line
1.In a identical drawing, the width of 1.同类图线规格一致 uniformity solid should substantial agreement.
2.虚线、点画线和双点画线 2.If the dotted line, stipple string and 相交时，应在画线处相交
（单 位）
20 45 130 15 15 45
12
二、比例 Scale（GB/T 14690－1993） 图样中图形与其实物相应要素的线性尺寸之比
The ratio between graphic linear dimension of drawing and the homologous linear dimension of the practicality is called scale.
3.The dimension on the drawing is the last finish size. 3. 图样上的尺寸为图样所示机件的最后完工尺寸。
4.Every dimension of the mechanical component is labeled only once 4. 机件的每一尺寸一般只注一次，并应注在最明显的 generally, and the dimension should be labeled at the most vivid 位置上。 drawing to reflect the structure.
The dimensioning must be filled in with the true size
Ø8 Ø8
The non-relevance between dimension and drawing scale
16 (a) 1:2
17
16
17
尺寸数字与画图 比例无关
16
不同比例的视 图应加以标注
Font sample 字体示例
1. Sample of long imitation song-dynasty Chinese
长仿宋体汉字示例 2. Sample of Latin letter 拉丁字母示例
The capitalization and italic of A Font A型字体大写斜体
Chapter 1 Basic Drawing Knowledge 第1章 制图基本知识
§1–1 Basic Stipulation for Technical Drawing GB 技术制图国家标准的基本规定
§1–2 Dimensioning 尺寸注法 §1–3 Geometry Drawing 几何作图 §1–4 Size Analyzing, Dimensioning and Drawing Steps in Planar Drawing 平面图形的尺寸分析、尺寸注法与画图步骤
细点画线的画法
超出图 形约 3~5mm
(a) 正确
(b) 错误
细点画线两 端应是画线 不能是点
圆心必须是 画线相交
用细实线代替 较短点划线
圆心应是画 线相交，不 能是点
超出图 形太长
§1－2尺寸注法
Dimensioning
尺寸标注要求做到：正确、完整、清晰、合理。
所谓正确，即尺寸标注要符合有关国家标准的要求；所谓完整， 即尺寸注写必须齐全，要求做到不多、不少、不重复；所谓清 晰，即尺寸布局明显、有规律，便于看图；所谓合理，即所注 尺寸既要保证设计要求，同时又要考虑加工和测量时的方便。 While dimensioning the drawing, the fellow rules must be obey: exactness, integrity, clearness, reason. The exactness means the dimension must concern the GB.The integrity means the dimension must written uniform full, and not much, not a little and not repeat. The clearness means the dimension layout distinctness, law, and facilitate see the drawing.The reason means the dimension as well as guarantee design requirement and consider the convenience of process and measure.
A2
420 ×594
A3
297 ×420
A4
210 × 297
尺寸（B*L） 841 × 1189
图幅 Drawing size
图框 Drawing boundary
标题 栏 Title bar
(a)
(b)
Non-binding edge type for drawing boundary 不留装订边的图框格式
§1－1 Basic Stipulation for Technical Drawing and Mechanical §1－1GB 国家标准《技术制图》与《机械制图》的 Drawing
基本规定
Size and format 图纸幅面 of drawing Scale Font
及格式
比例 字体
Drawing string
（二）尺寸的构成 Composing of the dimension 尺寸构成的三要素: 尺寸界线、尺寸线、尺寸数字
Three elements: size borderline, dimension line and dimension figure.
2×Ø8
90º
38
25
38 75
≥4d
d为粗实线的宽度
（a）
（b）
Binding edge type for drawing boundary 留有装订边的图框格式
简化标题栏格式
The format of simplified title bar
14 45 14 25
8 7
序号
名
称
数量
材
料
备
注
（图
名）
（图
比例
号）
6 6
34
重量 数量
6 6 6
制图 校对 审核
图线 Dimensioning 尺寸注法
一、图纸幅面及格式（GB/T 14689－1993）
The size and format of drawing
A1 841 A0
五种幅面 Five kinds of basic size ： A0 ~ A4
A3 A4
A2
1189 幅面代号
A0
A1
594 × 841
§1－2尺寸注法
2×Ø8
Dimensioning
尺寸标注要求做到：正确、完整、清晰、合理。 （一）基本规则 Basic rule
38 25 38 75
1.Dimension on the drawing is the 1. 图样上所注尺寸应为机 real size of the mechanical component, 件的真实大小，与图样大 which has no relation to the size and 小及绘图精度无关。 accuracy of drawing. 2.2. 图样中所注尺寸一般以 The unit of the drawing dimension is commonly millimeter (mm) 毫米为单位。
The lower case and italic of A Font A型字体小写斜体
3. Demonstration of Arabic numerals 阿拉伯数字示例
Italic 斜体 Lifting 直体
A Font A型字体
Italic 斜体
4. Demonstration of Roman numerals 罗马数字示例
绘图时应注意 选用标准比例 图面 ：实物
Drawing: Practicality
原值比例 放大比例 缩小比例 1:2
1:1
5:1 5×10n:1 2:1 2 ×10n:1 1:2×10n 1:5 1 × 10n:1 1:5 ×10n 1:10 1:1×10n
注意 图样上标注尺寸时必须按 Notice： 机件的实际尺寸填写。
two-stipple string had any intersect, they must intersect at the lineation.
3.虚线是实线的延长线时， 3. The dotted line is the extension cords 留有空隙；否则不留空隙
of solid line, leaving gaps ; otherwise, without leaving any gaps. of symmetry ,all of them should go beyond contour 3 to 5 mm.
If some of the parts had been drawn with different scale, it must be given addition label
(b) 1:1
Ⅰ
(c) 2:1
Ⅰ 2:1
17
Ø8
三、字体 Font（GB/T 14691－1993）
Typeface skill whole, stroke clarity, interval uniformity, 字体工整、笔画清楚、间隔均匀、排列整齐 arrange tidiness.