Find out velocity on bell crank lever:

Find out velocity of E on bell crank lever in a wrapping machine illustrated in Figure in terms of angular velocity 'w' of crank O₂A.

Solution:-

Total no. of links = 6

∴ Total no. of I.Cs = (6 × 5)/2 = 15

Circle diagram may be used to situate the instantaneous centre. Six instantaneous centres might be marked on the circle through joining points. O₂ A B O₄ is a four bar chain and I₁₃ can be resolute as in previous Example 4.1. Likewise I₁₅ lies on intersection of lines joining I₁₃ along with I₃₅ & I₁₆ with I₅₆. Other remaining instantaneous centres required not to be determined as they are not needed to determine requisite answer.

Putting for V_D & V_C

Also V_A = ω × I₁₂ A =ω r where I₁₂ A = r (radius of crank)