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0593_C16_fm Page 569 Tuesday, May 7, 2002 7:06 AM

Mechanical Components: Cams 569

Problems

Section 16.4 Graphical Constructions: The Follower Rise Function
P16.4.1: Consider a cam in the shape of an ellipse rotating about a focus point. Let the
ellipse have semi-major axis length a and semi-minor axis length b as in Figure P16.4.1.
Let c be the distance from the ellipse center to the focus. Thus, from elliptic geometry a,
b, and c are related by:

a = b + c 2
2
2
Following the procedure outlined in Section 16.4, obtain a graphical representation of the
follower rise function. Let a = 2 in. and b = 1.25 in.

b
O F
a c
FIGURE P16.4.1
A cam in the shape of an ellipse.

P16.4.2: Repeat Problem P16.4.1 if a = 5 cm and b = 3.25 cm.

Section 16.5 Graphical Construction: Cam Profiles
P16.5.1: Let a follower rise function have the shape of a cosine curve and be defined as:

A +
+
h θ () = [1 cos ( θ π)]
Use the procedure outlined in Section 16.5 to determine the cam profile if A = 1.5 inches.
P16.5.2: Repeat Problem P16.5.1 if A = 5 cm.

Section 16.6 Graphical Construction: Effect of Cam–Follower Design
P16.6.1: Repeat Problem P16.4.1 if the follower axis is offset from the cam axis by a distance
d as represented in Figure P16.6.1. Let a, b, and d have the values a = 2 in., b = 1.25 in.,
and d = 0.25 in.

b
O F
a c
FIGURE P16.6.1
A cam–follower axis offset from the
cam rotation axis.