機械製圖基本視圖包括（機械製圖組合體的視圖與形體構思）

2023-05-27 09:55:31 9

今天我們學習《機械製圖》——組合體的視圖與形體構思第一部分的內容。今天的主要內容是三視圖的形成和投影關係和畫組合體的視圖。Today we are studying Mechanical Drawing - Projection of three dimensions part 4. Today's main topic is the intersection of two revolving body surfaces.

1.主視圖——自前向後投射，在正立投影面上所得的視圖

俯視圖——自上向下投射，在水平投影面上所得的視圖

左視圖——自左向右投射，在側立投影面上所得的視圖

2.三視圖之間的投影關係可概括為：

主，俯視圖長對正；

主，左視圖高平齊；

俯，左視圖寬相等，前後對應。

1.Main view - the view projected from front to back in the orthographic plane

Top view - the view projected from top to bottom on the horizontal projection plane

Left view - projected from left to right, in the side projection

2.The projection relationship between the three views can be summarized as follows

main, top view long to square.

main, left view flush in height.

Top, left view is equal in width and corresponds to the front and back.

No.1 三視圖的形成

3.組合體按期形成方式，通常分為疊加型，切割型和綜合型。

4.畫組合體視圖的方法與步驟

畫組合體視圖的基本方法是形體分析法。形體分析法是假想將一個複雜的組合體分解為若干基本體，並對它們的形狀和相對位置進行分析的一種思考方法。

（1）運用形體分析，逐個畫出各基本體。同一基本體的三視圖應按投影關係同時畫出，而不是先畫完組合體的一個完整的視圖後，再畫另一個視圖。這樣既能保證各基本體之間的相對位置和投影關係，又能提高繪圖速度。

（2）畫每一個基本體時，應先畫反映該部分形狀特徵的視圖。例如圓筒和支承板再主視圖上反映其形狀特徵，宜先畫主視圖，再畫俯，左視圖。

（3）在逐個畫各個基本體的三視圖時，還應同時思考和檢查基本體表面連接處的投影是否正確，若發現錯誤應立即修改。例如支承板兩側面與圓筒表面相切，支承板的側面輪廓線在俯，左視圖上應畫到切點處；凸臺與圓筒相交，在左視圖上要畫出內，外相貫線；肋板與圓筒相交，在左視圖上要正確畫出肋板側面與圓柱面的交線。

3. Combined body by the period of formation, usually divided into superposition type, cutting type and integrated type.

4. Methods and steps of drawing the view of the combination

The basic method of drawing the view of the combination is the form analysis method. Form analysis method is a hypothetical decomposition of a complex combination into a number of basic bodies, and their shape and relative position to analyze a method of thinking.

(1) Using form analysis, draw each basic body one by one. The three views of the same basic body should be drawn simultaneously according to the projection relationship, not after drawing a complete view of the combination first, then another view. This can ensure the relative position and projection between the basic bodies, but also to improve the drawing speed.

(2) When drawing each basic body, you should first draw a view that reflects the shape of the part of the characteristics. For example, if the cylinder and the support plate reflect their shape features on the main view, it is appropriate to draw the main view first, and then draw the top and left views.

(3) In drawing the three views of each basic body one by one, you should also think about and check whether the projection of the basic body surface connection is correct, if found in error should be immediately modified. For example, if both sides of the support plate are tangent to the surface of the cylinder, the side profile of the support plate should be drawn on the top and left views to the tangent point; if the tab intersects with the cylinder, the inner and outer coherence lines should be drawn on the left view; if the rib plate intersects with the cylinder, the intersection line between the side of the rib plate and the cylindrical surface should be drawn correctly on the left view.

No.2畫組合體的視圖