Dynamic Characteristics and Design Criteria for a Class of Vibration-Producing Machines

Abstract

Many self-contained machines used in industry serve to generate a sustained mechanical vibration for performing such diverse operations as vibration testing, hammering, material conveying, impacting, and screening. A particular class of such machines having only plane motion is idealized as a dynamic “vibrator” consisting of a two-mass, spring-coupled system driven internally by an oscillatory force. A dynamic analysis of this system is presented to show that the steady-state motion has both translational and rotational components. Specific methods are given for predicting the resultant direction and amplitude of motion for any point in the vibrator system. Results of the dynamic analysis show quantitatively the effect of system resonance, mass distribution, gravity-center configuration, and internal damping on vibrator operation and these design factors are discussed in terms of typical vibrator applications.