Question

3-15 Figure P3-4 shows a non-Grashof fourbar linkage that is driven from link O2A. All dimensions are in centimeters (cm) Find the transmission angle at the position shown. Find the toggle positions in terms of angle AO204 Find the maximum and minimum transmission angles over its range of motion by graphi- cal techniques Draw the coupler curve of point P over its range of motion a. b. c. d.

Answer 1

a)

To find the transmission angle, we draw the mechanism to scale.

102.900

Transmission angle is:

$180-102.9 = 77.1^0$

b)

Toggle occurs when, links AB and BO₄ are colinear.

Using cosine rule

$cos\theta_2 = \frac{O_2A^2+O_2O_4^2-(BO_4+AB)^2}{2*O_2O_4*O_2A}$

$cos\theta_2 = \frac{5^2+9.5^2-(5+4.4)^2}{2*5*9.5}$

$cos\theta_2 =0.283$

$\Rightarrow \theta_2 = \pm73.56$

c)

Minimum transmission angle is zero.

Maximum transmission angle is: 90 degree

90%

d)