Mechanical Separation Phenomena in Picking Mechanisms of Fly-Shuttle Looms

Mechanical separation between cam and pick ball in fly-shuttle looms gives rise to impact and vibration which causes significant noise emission. Elimination of separation is analyzed using a mathematical model which simulates the dynamic response characteristics of the system. Parameters considered in the study include equivalent stiffness, mass, and damping of the system, amplitude of excitation, effect of preload provided by a retaining spring, and operating frequency. Combinations of system parameters and operating conditions which give rise to separation are predicted by examining the contact force developed between cam and cam-follower. Equations and graphs are presented that specify the preload required to eliminate separation as a function of the system parameters.