《工程制图》(双语)讲义ppt课件

1、Engineering GraphicsNorth China Electric Power University.Yang Zhiling: Office address：F-824Please prepare the book:.Please prepare two kinds of pencil: H and 2B, a pair of triangles and a compass. Graphic Language and DesignIntroduction1History of Technical Drawing2Summery34Projection

2、.Design ProcessA design process starts with a concept or an idea.The first stage of the project begins with the identification of a particular need for a product.The second stage involves the creation of a variety of options or design ideas. These idea may be in the form of sketches, and include mat

3、hematical computations.The third stage is the refinement of the preliminary designs. Possible solutions to the problem are identified.Design ProcessThe fourth stage involves refinement and selection of a particular design. Here the project is put in a more formal, finalized state using assembly draw

4、ings or models. This stage requires close attention to how the part is to be manufactured or produced.In the fifth stage, detail drawings are prepared. The result is a complete set of working drawings.The sixth stage in the design process is the manufacturing and production of product, or the constr

5、uction of a system. .SKETCHES and DRAWINGS.SKETCHES and MODELS.ASSEMBLY DRAWINGS.Refinement of the model.DETAIL DRAWINGS.PLANS and ELEVATIONS.Definitions.DRAWINGA drawing is a graphic representation of a real thing, an idea, or a proposed design for later manufacture or construction. Drawings may ta

6、ke many forms, but the graphic method of representation is a basic natural form of communication of ideas that is universal and timeless. .GRAPHIC LANGUAGEAlthough people around world speak different languages, a universal graphic language has existed since the earliest times.The ancient letters and

7、 words are graphic representations.Ancient Egyptian Character.TECHINICAL DRAWINGGraphic representation has been developed along two distinct lines, according to purpose: artistic technicalFrom the beginning of recorded history, people have used drawings to represent the design of objects to be built

8、 or constructed. . EARLY TECHNICAL DRAWING An aerocraft drawing, by Leonardo da Vinci. MODERN TECHNICAL DRAWINGGaspard Monge (1746-1818) developed the principles of projection that are now the basis of our technical drawing. He is considered the “inventor of descriptive geometry. In 1900, the first-

9、angle projection and third-angle projection were established.ProjectionObjectProjection.First Angle Projection and Third Angle ProjectionVVFirst angle projectionThird angle projection.What will we learn?3D 2D.3D 2D.What will we learn?2D 3DWhats this.2D 3D.Another Answer.What will we learn?Some speci

10、al drawing skills.What will we learn?.INTRODUCTION TO CADComputerAidedDesignComputerAidedDraftingCAD.APPLICATION OF CAD2D Working Drawing.APPLICATION OF CAD3D Part Model.APPLICATION OF CADSurface Modeling.APPLICATION OF CADVirtual Assembly.APPLICATION OF CADVirtual Assembly.CAD SOFTWAREAutoCAD/Inven

11、torProEngineerSolidWorksCATIAUG IICAXA.INTRODUCTION TO CADCADD Computer Aided Design and DraftingCAM Computer Aided ManufacturingCIM Computer Integrated ManufacturingCAE Computer Aided EngineeringCG Computer Graphics.OTHER APPLICATIONImage Process.Game, Film and CartoonOTHER APPLICATION.SUMMARYThe g

12、raphic language is the universal language used by every engineering team designing and developing products throughout the world. Every technical drawing is based on standard that prescribe what each symbol, line, and arc means.We need to train our ability of spatial imagining, learn how to transform

13、 3D object to 2D projections and 2D projections to 3D object.For train your ability of spatial imagining, you must do exercises yourself.Lesson 1 Basic DraftingDrafting Standard1Drawing Equipment2Geometric Construction3Dimension4.Drawing Equipment.Drawing Equipment.Drawing Equipment.Drawing Equipmen

14、t.DRAFTING STANDARDAmerican National Standard Drafting Manual Y14Chinese National Satandard for Mechenical Drawings These sections outline the most important idioms and usages in a form that is acceptable to the majority. They are considered the most authoritative guide to uniform drafting practices

15、 in this country today. .Drafting StandardPRC National Standard (abbreviated to GB) is the standard work on drafting practice. National Standard contains seventeen separate Standards, which are set by referring to the ISO (International Organization for Standardization) Standards, such as GB/T 14689

16、-1993 for Sizes and layout of drawing sheet, GB4457.4-1984 for Lines.Line Types (GB/T4457.4-1984)NameTypeWidthUseThick solid linebVisible lineThin solid lineb/3Dimension line, Extension line,Section lineDashed lineb/3Hidden lineWave lineb/3Short-break lineZigzag lineb/3Long-break lineThin dot-and-da

17、sh lineb/3Center lineDouble dot-and-dash lineb/3Phantom line.Drawing Equipmentfor thin linefor thick line.Thickness of the line.Application of lines.Metric System and Scale (GB/T14690-1993)1 mm = 1 millimeter (1/1000 of a meter)1 cm = 1 centimeter (1/100 of a meter) = 10 mm1 dm = 1 decimeter (1/10 o

18、f a meter) = 10 cm = 100 mm1 m = 1 meter = 100 cm = 1000mm1km = 1 kilometer = 1000m =100,000 cm = 1,000,000 mm.Metric System and Scale (GB/T14690-1993)The scale is the relation between the dimensions of drawing of an object and the actual dimensions.Scales established by the Chinese National Standar

19、d:Full size：1:1Enlargement：2:1, 2.5:1, 4:1, 5:1, 10:1 etc.Reduction：1:1.5, 1:2, 1:2.5, 1:3, 1:4, 1:6, 1:10 etc.Whatever the scale, the dimensions on the drawing indicate the true size of the object, not of the view.Lettering Forms (GB/T 14691-1993)The following sizes of characters are recommended: 2

20、0, 14, 10, 7, 5, 3.5 and 2.5.Lettering Forms (GB/T 14691-1993) The letters and numerals are either inclined 15 to the right, or vertical (upright).Sheet Sizes and Layout (GB/T14689-1993)The Standard establishes five preferred sizes for drawings as below：A0、A1、A2、A3、A4. Sheet sizes： A0:8411189 A1:594

21、841 A2:420594 A3:297420 A4:210297A sheet with border lines and a title blocks is called a layout.Margin and Border The vertical layout and horizontal layout are shown in Figures as below: If the filing margin for perforation is necessary, a=25, A0A2:c=10, A3、A4:c=5.Margin and Border If the filing ma

22、rgin for perforation is not necessary, then A0A1:e=20mm, A2A4:e=10mm.Title Block GB10609.1-1989 is a Standard for title block. The title block for study drawing and detail drawing are suggested in Figures as below:.Freehand Sketches (1)Drawing Lines:Drawing Angles:.Freehand Sketches (2)Drawing Circles:Drawing Ellipses:.Drawing a Pentagon.Drawing a Hexagon.Ellipse Construction.Drawing