Page:The Kinematics of Machinery.djvu/559

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CAM PAIRS.


�537


�these class signs. This holds good also for those pairs in which a spur-wheel becomes a rack P z , in which P may be treated as a special case of C.

145. Cam Pairs.

The pairing between the links a and b in the cam trains Fig. 368 and 369 may be considered a special case falling under the class (_T,). In the cases shown we have a non-circular cylinder C


���FIG. 368.


�FIG. 369.


�paired with a tooth Z '; the general case would be a non-circular hyperboloid H paired with a tooth of general form Z. The pair may be called the general cam pair and written

H,ZOT GET,;).

L


��FIG. 370.


�FIG. 371.


�As subdivisions we have, besides (H,z)

(;) and (JTJ ((7,:) and (#,,)