2012第2講－表達(dá)機件的常用方法-I

1、1第 二 講表達(dá)機件的常用方法-IFundamental methods for representation of mechanical parts機械圖樣的五種基本表示法 Five basic methods for mechanical part drawing： 視圖 Views 剖視圖 Sectional Views 斷面圖Cross-Sections 局部放大圖Local Enlarged Views 簡化畫法技術(shù)制圖國家標(biāo)準(zhǔn)GB/T 4458.12002 規(guī)定本講內(nèi)容2一、基本視圖Principal Views 右視圖 Right 主視圖 Main (Front) 俯視圖 Top

2、 左視圖 Left 后視圖 Back 仰視圖 Bottom 形成Generation從右向左投射從下向上投射從后向前投射2.1 視圖Views表達(dá)機件外部結(jié)構(gòu)形狀Representing Exterior construction3 六個投影面的展開 Open the Projection Box主視Main俯視Top左視Left右視Right后視Back仰視Bottom4 六面視圖的投影對應(yīng)關(guān)系 Relations between six views長Length高Height寬Width上Top下Bottom左Left右Right前Front后Back右Right左Left 度量對應(yīng)關(guān)系

3、：仍遵守“三等”規(guī)律 Rule of Tri-equality 方位對應(yīng)關(guān)系：主視Main俯視Top仰視Bottom左視Left右視Right后視Back 長Length主視俯仰視長相等且對正Front and Top views are equal in length主視左右后視高相等且平齊Front and Left views are equal in height俯視左右仰視寬相等且對應(yīng)Top and Left views are equal in width 除后視圖外，靠近主視圖的一邊是物體的后面，遠(yuǎn)離主視圖的 一邊是物體的前面。All views but back view ha

4、ve the back side of the object close to the main view and front side of the object away from the main vies.5完成所給物體的其余四個基本視圖，并徒手畫斜二軸測圖。Complete the other four principal views of the given object( front and top views）,sketch the cabinet drawing freehand. 這不是斜二軸測Not Cabinet drawing6二、向視圖Reference Arrow

5、 Views向視圖是可自由配置的視圖 Freely Positioned Views 在向視圖的上方標(biāo)注大寫字母，在相應(yīng)視圖附近用箭頭指明投射方向，并標(biāo)注相同的字母。 Each freely positioned view should be identified by a capital letter( say ,A) placed immediately above the view and the same letter is placed near the arrow indicating the direction of projection in the relevant view

6、.CDDBBC自由配置Freely Arranged Six ViewsEEFF按基本位置配置Principal Arrangement of Six Views7 在理解向視圖這一概念及其配置法時必須注意，可以自由配置的向視圖，自由是不能超越一定限度的The freedom should be limited： 不能傾斜投射，應(yīng)當(dāng)正射。如果傾斜投射則所得不再是向視圖，而是斜視圖。The projection should be right not oblique or the view would be an inclined view. 不能只畫出部分圖形，必須完整畫出投射所得圖形。否則為

7、局部視圖而非向視圖。The whole projection should be drawn or the view would be local view. 不能旋轉(zhuǎn)配置，即不能是相應(yīng)基本視圖旋轉(zhuǎn)后的圖形。否則不再是向視圖，而是輔助視圖了。The reference arrow view cannot be rotated or it would be an auxiliary view.8三、局部視圖 Local Views 將物體某一部分向基本投影面投射所得的視圖。View by projecting of local construction of the whole object注意

8、事項Note ：用帶字母的箭頭指明要 表達(dá)的部位和投射方向， 并注明視圖名稱。Reference arrow and capital letter局部視圖的范圍用波浪 線表示。當(dāng)表示的局部 結(jié)構(gòu)是完整的且外輪廓 封閉時，波浪線可省略。Wavy or zigzag line confine局部視圖可按基本視圖 的配置形式配置，也可 按向視圖的配置形式配 置。Local view can be placed in the same way as the principal or the reference arrow view.BAAB910四、斜視圖Inclined Views問題：當(dāng)物體的表面

9、與投影面成傾斜位置時，其投影不反映實形。Problem：The Projection of inclined surface of object doesnt show the true shape. 增設(shè)一個與傾斜表面平行的輔助投影面。Add an auxiliary projection plane parallel to the inclined surface.解決方法Solution： 將傾斜部分向輔助投影面投射。Project the inclined part to the auxiliary projection plane.VHPA 斜視圖是物體向不平行于基本投影面的平面投射

10、所得的視圖。用于表達(dá)機件傾斜結(jié)構(gòu)的外形。Inclined views are projections of object onto a plane not parallel to any principal plane of projection. Inclined Views are used for the exterior construction of inclined part of the object.11AA斜視圖的畫法Drawing注意事項Note：A 繪制斜視圖時，通常只畫出傾斜部分的局部外形，而斷去其余部分，通常按投射方向放置和標(biāo)注。Usually only the in

11、clined part is drawn in inclined view . 斜視圖的斷裂邊界用波浪線或雙折線繪制Wavy or zigzag line is used to the border. 允許旋轉(zhuǎn)配置，但需注明。Inclined view may be rotated to a more convenient position .箭頭指明旋轉(zhuǎn)方向，字母靠近箭頭一側(cè) Letter placed near the arrow which indicates the rotating direction舊標(biāo)注為“A向旋轉(zhuǎn)”12 斜視圖旋轉(zhuǎn)配置時，旋轉(zhuǎn)方向和角度的確定應(yīng)考慮便于看圖。旋轉(zhuǎn)

12、符號的箭頭指向與旋轉(zhuǎn)方向一致。旋轉(zhuǎn)角度不大于45。視圖名稱大寫拉丁字母在箭頭端，需要給出旋轉(zhuǎn)角度時，角度寫在字母之后。 How to rotate the inclined view depends the convenience of understanding. The rotation angle usually is less than 45 . Rotation angle should be written after the Letter if necessary.13作物體的A向局部視圖和B向斜視圖Construct the partial view A and the inc

13、lined view B of the object14 視圖小結(jié) Conclusion on Views基本視圖向視圖局部視圖斜視圖六面視圖六面視圖局部圖形完整圖形局部圖形完整圖形固定配置、不標(biāo)注任意配置、標(biāo)注基本視圖方式配置向視圖方式配置 投射方向或旋轉(zhuǎn) 配置、標(biāo)注 視 圖 152.2 剖視圖 Sectional Views問題： 當(dāng)機件的內(nèi)部形狀較復(fù)雜時，視圖上將出現(xiàn)許多虛線，不便于看圖和標(biāo)注尺寸。Problem: The numerous dash lines which show the complicated interior construction make the drawi

14、ng difficult to interpret.解決辦法Solution？采用剖視圖 Sectional viewBAAB161718一、剖視圖的概念 Concept of Sectional Views 剖視圖的形成 Generation 假想用一剖切面將機件剖開，移去剖切面和觀察者之間的部分，將其余部分向投影面投射，并在剖面區(qū)域(切削平面與機件接觸的面)內(nèi)畫上剖面符號。By imagining the object to be cut by a cutting plane and removing the portion near the observer, we project th

15、e remaining portion and fill the section area (the surfaces touched by the cutting plane )with section lines .192.剖視圖的畫法 Drawing 確定剖切面的位置 Define the cutting plane 想象哪些部分材料被切到？剖面區(qū)域的形狀？哪些部分投影時可看到？Imagine removed half, section area and the visible ？ 在剖面區(qū)域內(nèi)畫上剖面符號。Fill the section area with section lines

16、.虛線不畫Not dash lines any more20AAA - A3.剖視圖的標(biāo)注Label the sectional views 剖切符號 :表示剖切面起、迄和轉(zhuǎn)折位置（用粗實線表示）及投射方向（用箭頭表示） 。 Section signs show how the cutting plane goes through the object (thick solid lines) and the direction of projection (by arrow) . 剖視圖的名稱。大寫拉丁字母在剖視圖上方。為便于讀圖時查找，應(yīng)在剖切符號附近注寫相同的字母。Name of the

17、section view by capital letter. 剖切線：指示剖切面的位置 (細(xì)點畫線)。一般可省略。 Cutting Plane lines are dot-and-dash lines which are usually omitted.2122剖切平面可以是傾斜的斜剖視圖Inclined views in section23當(dāng)剖視圖按投影關(guān)系配置，中間又無其他圖形隔開時，可省略表示投射方向的箭頭The arrows can be omitted when the section view placed by the default projection direction省

18、略標(biāo)注投射方向的剖視圖Section view without any label24當(dāng)單一剖切平面通過機件的對稱或基本對稱面，切剖視按投影慣性配置，中間又無圖形隔開時，則不必標(biāo)注。All the labels can be omitted when the section view with single cutting plane is placed by the default projection direction 省略標(biāo)注的剖視圖Section view without any label25在剖視圖中的細(xì)薄構(gòu)件THIN MEMBERS IN SDCTIONAL VIEWSAAAA

19、 對于機件的肋板，如按縱向剖切，肋板不畫剖面符號，而用粗實線將它與其鄰接部分分開。橫向剖切肋板則畫出剖面線。Rib should be separated by thick solid lines but not section-lined if the cutting plane cuts along the center plane of the rib ,while section-lined if the cutting plane passes crosswise through the plate.不正確Incorrect正確Correct正確Correct26 選擇剖切面位置時，

20、一般不與輪廓線重合。必要時，也允許緊貼機件表面進(jìn)行剖切，此時，該表面不畫剖面線。Cutting plane doesnt coincide with contour surface. If necessary, The surface should be drawn without section lines沿表面剖切的剖視圖Section view with cutting plane along the surface27剖面符號SYMBOLS FOR SECTIONS金屬材料Metallic material非金屬材料Nonmetallic material木材(縱剖面)Wood（lon

21、gitudinal Section）木材（橫剖面）Wood (Transverse section)木制膠合板Plywood混凝土Concrete磚Brick電氣繞圈繞組Electric windings玻璃及供觀察用的其他材料Glass and othertransparent materials for observation液體Liquids格網(wǎng)Grid4. 畫剖視圖的注意事項 剖切平面的選擇：通過機件的對稱面或軸線且平行或垂直于投影面。The cutting plane usually through the symmetry or axis and parallel or perpe

22、ndicular to the projection plane. 剖切是一種假想，其它視圖仍應(yīng)完整畫出，并可取剖視。Imaginary cutting doesnt affect other views29 剖切面后方的可見部分要全部畫出。The feature behind cutting plane should be drawn.錯誤Incorrect正確Correct30A-AAA31在剖視圖上已經(jīng)表達(dá)清楚的結(jié)構(gòu),在其它視圖上此部分結(jié)構(gòu)的投影為虛線時,其虛線省略不畫。但沒有表示清楚的結(jié)構(gòu)，允許畫少量虛線。Adding hidden lines to a section view co

23、mplicated the drawing, defeating the purpose of clarifying with a section，So a minimum number of hidden lines are needed to represent features other than the primary one shown by the section. AAAA32 不需在剖面區(qū)域中表示材料的類別時，剖面符號可采用通用剖面線表示。通用剖面線為與主要輪廓或剖面區(qū)域的對稱線成45角的細(xì)實線；同一物體的各個剖面區(qū)域，其剖面線畫法應(yīng)一致。Different section

24、line symbols can be used to represent various types of materials. However, the general purpose section line symbol used in most section view drawings is thin solid lines being drawn at a 45 degree angle . If the visible outline to be sectioned is drawn at a 45 degree angle, the section lines are dra

25、wn at a different angle, such as 30 degrees. 不好 Poor好 Good不好 Poor好 Good33二、剖視的種類 Section view types1.全剖視Full Section用剖切面完全地剖開物體所得的剖視圖。 A full section view is made by passing the cutting plane fully through the object.外形較簡單，內(nèi)形較復(fù)雜，而圖形又不對稱時。Full section is used to represent object which has simple exte

26、rior feature but complicated interior and nonsymmetrical.適用范圍：AAAA34不能清楚表達(dá)外形Cant tell the external feature clearly.AAAA存在什么問題？What is the problem?35解決辦法Solution：以對稱線為界,一半畫視圖,一半畫剖視。Cutting plane passes through half way through the object. Half section and half external feature are drawn symmetric to

27、the axis.2. 半剖視 Half Section已表達(dá)清楚的內(nèi)形虛線不畫Hidden lined are omittedAA分界線為中心線Center line to separate the sectioned half from the unsectioned half of the half section view.36BB適用范圍：內(nèi)、外形都需要表達(dá)，而形狀又基本對稱時。Half section views are most often used on objects that are symmetrical and complicated in both interior

28、and external.AAAABB半剖視 Half Section37BB3. 局部剖視 Broken-out sectionAAAABB用剖切平面局部地剖開物體所得的剖視圖。A broken-out section is used to show interior features of a part by breaking away some of the object.局部剖視部分義波浪線與周圍斷開。A wavy break line separates the sectioned from un-sectioned half of the view. 38BB3. 局部剖視Brok

29、en-out sectionBBAAAA 可用雙折線代替波浪線。The break lines can be zigzag lines.39適用范圍： 局部剖是一種較靈活的表示方法，適用范圍較廣。Broken-out section is a rather flexible and widely used method.只有局部內(nèi)形需要剖切表示時。When the interior feature of only part of an object40實心桿上有孔、槽時，應(yīng)采用局部剖視。 Solid shaft with only local hole or slot.41 當(dāng)對稱機件的輪廓線與中心線重合， 不宜采用半剖視時。When contour line coincides with center line of a symmetrical object , broken-out section view is used instead of the half section.不好POOR好GOOD42AABBAA BB 當(dāng)機件的內(nèi)外形都較復(fù)雜，而圖形 又不對稱時。Broken-out