Page 505 - Cam Design Handbook
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THB14  9/19/03  7:58 PM  Page 493

                                   SPECIAL CAM MECHANISMS                  493




















                 FIGURE 14.42. Cam-modulated mechanism—epicyclic gears and moving cam, type 2.
































                         FIGURE  14.43. Cam-modulated  mechanism—epicyclic  gears
                         and fixed cam.

            14.27.6 Cam-Modulated Noncircular Gears

            In  some  designs,  it  has  been  proved  feasible  to  use  noncircular  gearing  for  a  variable
            angular velocity ration between the driving gear and the driven gear. Generally, noncir-
            cular gears are expensive and are utilized as a last resort. However, the previous cam and
            link mechanisms may become too complicated and bulky. Instead, cams combined with
            noncircular gears are used. A dwell period exists at the beginning and at the end of the
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