NONDIMENSIONAL ANALYSIS OF JUMP PHENOMENON IN FORCE-CLOSED CAM MECHANISMS


TUMER S. , UNLUSOY Y.

MECHANISM AND MACHINE THEORY, cilt.26, ss.421-432, 1991 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 26 Konu: 4
  • Basım Tarihi: 1991
  • Doi Numarası: 10.1016/0094-114x(91)90013-t
  • Dergi Adı: MECHANISM AND MACHINE THEORY
  • Sayfa Sayıları: ss.421-432

Özet

The elasticity of the follower train and return spring dynamics are incorporated in a general nondimensional analysis for follower jump in force-closed cam mechanisms. The follower train is represented by a lumped single degree-of-freedom model, and the return spring is considered as a continuous element. Knowing the harmonic content of the forcing function, utilization of four-pole parameters enables a straighforward computational procedure to be developed for the determination of jump speed. For a typical case of simple harmonic motion cam, an analytical expression is derived for the minimum preset of return spring to prevent cam-follower separation in terms of four dimensionless parameters; namely, the speed, damping, elasticity and mass factors. The analytical procedure developed is used to study the relative importance of follower train and return spring parameters on the jump phenomenon. Jump characteristics of simple harmonic and cycloidal motions are compared for varying dwell-angles of a dwell-rise-return (D-R-R) cam.