Page 243 - Cam Design Handbook

THB8 9/19/03 7:25 PM Page 231

CAM MECHANISM FORCES 231

Cycloidal curve
Modified
sine curve Simple harmonic curve
Torque,T

Dwell
0 b/4 b/2 3b/4 b
Dwell
Cam angle q
(a) External load, L, only
··
(Inertia load ~ y = 0).

Cycloidal curve
Torque,T Modified sine curve

Simple harmonic curve
Dwell

0 b/4 b/2 b/4 b
Dwell
Cam angle q
(b) Inertia load only
(external load L = 0).
FIGURE 8.9. Torque comparison of cam curves (DRD cam).

y A

r b
V S

V A
w

(a) Cam follower. (b) Velocity vector diagram.
FIGURE 8.10. Cam and reciprocating flat-faced follower.