The reciprocating rectilinear motion mechanism of Probs. 6.111–6.115 is often referred to...

The reciprocating rectilinear motion mechanism of Probs. 6.111–6.115 is often referred to as a quick return mechanism since it can move much more quickly in one direction than the other. To see this, we will determine the velocity of the bar in each of the two positions shown (position 1 when B is farthest from C and position 2 when B is closest to C) under the assumption that the disk, whose center is at A, rotates with a constant angular velocity ωAB = 120 rpm. Find the velocity of the bar in positions 1 and 2 for d = 0.12 m and for

(a) R/h = 0.3

(b) R/h = 0.8

Comment on which of the two R/h values would provide a better quick return and why.

Figure P6.116