Behavior of a New Type Dynamic Vibration Absorber Consisting of Three Permanent Magnets

Abstract

This paper presents some experimental and analytical studies on a new repulsive type dynamic vibration absorber consisting of three permanent magnets of thick disk type^(1)∼(2). These magnets are so arranged in a non-magnetic conductive or non-conductive cylinder that one magnet can move freely between the two fixed ones. The result showed that: (1) Repulsive force⁽³⁾ interacting between the two magnets may be assumed to be inversely proportional to the nth power of the center distance between the magnets. This assumption makes the analysis easier, and the results of the experiment show considerable coincidence with those of the analysis. (2) The new absorber may be able to control the resonant amplitude of the vibrating body which weighs several dozen times the free magnet. Further merits of the absorber are an eddy current damping generated in the conductive cylinder and arbitrary choice of the vibration direction as well as the frequency adjustability.