Page 31 - CITS - ED - Mechanical

ENGINEERING DRAWING - CITS

Fig 3

Exercise 2.13
Construct an involute of a heptagon (Polygon) in a circle of diameter 40 mm (Fig 4)
• Draw a polygon (heptagon) in a circle of φ 40 and mark the corners 0,1,2,.....6 etc.

• Extend each side of the polygon (heptagon) as shown.
• '1' as centre and 1-0 as radius, draw an arc OP 1
• '2' as centre and 2-P as radius, draw an arc P P 2
1
1
• Proceed in the similar way and draw arcs P P P P & P
3 4 5 6 7
• Now the curve `O' P P P ....P is the required involute.
7
3
1
2
Fig 4

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CITS :Engineering Drawing (Mechanical) - Exercise 2