Page 323 - Cam Design Handbook
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THB10  9/19/03  7:28 PM  Page 311

                                     CAM MANUFACTURING                     311













                                                Cam
                                                   Translating
                                                   Follower






                                     (a) Straight rib.






               Cam                    Follower


                                                             Stud


                                                                Cam
                                    Follower
                                                                no. 2
                                                  Cam no. 1

                   (b) Tapered rib.                (c) Conjugate cams.
               FIGURE 10.22. External double roller on cam.



            adjustment  is  sometimes  provided  for  reducing  backlash  and  preloading  the  roller.  In
            Fig. 10.21b we see concentric rollers of the same diameter but in a relieved groove. The
            undercut is difficult to produce accurately. The last type, and the most acceptable, is shown
            in Fig. 10.21c, where we see two concentric rollers of different diameters in a stepped
            groove.
               external double roller on cam:  In Fig. 10.22 are shown positive-drive double
            rollers on double surfaces. Figure 10.22a indicates a globoidal cam having a straight rib
            and a translating follower. Figure 10.22b has a tapered rib with a globoidal cam and an
            oscillating follower. An excellent choice for radial cams is realized by the application of
            conjugate or complementary cams, Fig. 10.22c. This arrangement is flexible and accurate
            and minimizes misalignment of contacting parts. It is also reliable for high-speed, high-
            mass systems giving low noise and low vibration. In all three cam followers shown, pre-
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