Practical and graphic work on drawing. Practical and graphic work on drawing b) Simple sections

Rice. 99. Tasks for graphic work No. 4

3) Are there any holes in the part? If so, what geometric shape does the hole have?

4) Find on each of the views all flat surfaces perpendicular to the frontal and then to the horizontal planes of projection.

2. Based on the visual representation of the parts (Fig. 99), make a drawing in the required number of views. Draw on all views and mark points A, B and C.

13. The order of constructing images in drawings

13.1. A method for constructing images based on analysis of the shape of an object. As you already know, most objects can be represented as a combination of geometric bodies. Therefore, to read and complete drawings, you need to know how these geometric bodies are depicted.

Now that you know how such geometric bodies are depicted in a drawing, and have learned how vertices, edges and faces are projected, it will be easier for you to read drawings of objects.

Figure 100 shows a part of the machine - the counterweight. Let's analyze its shape. What geometric bodies do you know that it can be divided into? To answer this question, let us recall the characteristic features inherent in the images of these geometric bodies.

In Figure 101, and one of them is highlighted in brown. What geometric body has such projections?

Projections in the form of rectangles are characteristic of a parallelepiped. Three projections and a visual image of the parallelepiped, highlighted in Figure 101, and in brown, are given in Figure 101, 6.

In Figure 101, in gray conditionally, another geometric body is highlighted. What geometric body has such projections?

You encountered such projections when considering images of a triangular prism.