Question

For the four-bar mechanism shown, if the link AB is the driver then the maximum transmission angle is

• A. zero
• B. 120°
• C. 90°
• D. 180°

Answer 1

The correct option is D 180°

a = 30 mm, b = 40 mm.

c = 40 mm, d = 50 mm,

Maximum transmission angle ${\mu }_{max}$ is given by

$\cos \mu =\frac{b^2+c^2-a^2-d^2+2ad\cos \theta }{2bc}$

$\cos \mu =\frac{{40}^2+{40}^2-{30}^2-{50}^2-2\times 50\times 30}{2\times 40\times 40}$

$\therefore {\mu }_{max}={180}^{\circ }$