Degradation Phenomenon of Electrical Contacts Using a Micro-Sliding Mechanism - Minimal Sliding Amplitudes Estimated under Some Conditions by the Mechanism

Authors have developed a mechanism which gives damping vibration to electrical contacts by periodical hammering-oscillation and another mechanism which gives reciprocal micro-sliding to electrical contacts directly driven by a magmetostrictive actuator or a piezo-electrical one. It is shown that each mechanism is able to make a test simulate an actual degradation phenomenon on electrical contacts by the influence of micro-oscillation. By using the above mechanisms and their models they have studied the influences of micro-oscillation on contact resistance. In this paper, first, it is shown that there is degradation phenomenon of electrical contacts by experimental results using micro-sliding mechanism (MSM). And it is also shown that the phenomenon depends on contact frictional force between a male pin and a female pin in a connector and on sliding amplitude directly driven by a magmetostrictive actuator. Second, it is indicated that there are minimal sliding amplitudes estimated in six conditions. The conditions are two types of input waveform whish are sinusoidal and rectangular and three types of frictional force between a male-pin and a female-pin in an actual connector which are usual, middle and smaller. Finally, it is suggested that there are non-linear elements in the system from the minimal sliding amplitudes. Because of phase plane analyses of contact voltages it is clear that there are limit cycle and bifurcation which are typical of non-linear phenomenon. It is, however, not yet clear what element is major and what element is minor in the system.