Page 479 - Cam Design Handbook

THB14 9/19/03 7:58 PM Page 467

SPECIAL CAM MECHANISMS 467

r n

0

FIGURE 14.12. Tangent cam—translating roller follower.

a = ( R + R )w 2 (12 2 q )sec q in sec . 2 (14.14)
+ tan
b r t t
As before, the positive and negative accelerations depend on the cam proportions.
Furthermore, the following relationships are apparent
R - r n = E - = E cos b (14.15)
h
2
2
b
or the total rise
)
-
h = E (1 cosb in. (14.16)
2
Note that a rotating cam contacting an oscillating curved-face follower has a quadric equiv-
alent mechanism. The same cam mechanism (except that the follower has a flat face) may
be replaced by a slider-plane equivalent mechanism.
14.10 CIRCULAR ARC CAM—TRANSLATING
FLAT-FACED FOLLOWER

Now we shall use a circular arc cam but with a flat-faced follower. In Fig. 14.13 we
see the Scotch yoke equivalent mechanism. As before there are two different equivalent