Degradation Phenomena of Electrical Contacts Using Hammering Oscillating Mechanism and Micro-Sliding Mechanism- Contact Resistance and Its Model

Authors have developed the mechanism which gives damping vibration to electrical contacts by reciprocal hammering-oscillation and the other new mechanism which gives periodical micro-sliding to electrical contacts directly driven by a magmetostrictive actuator or a piezo-electrical one. It was shown that each mechanism was able to make a test simulate an actual degradation phenomenon on electrical contacts by the influence of micro-oscillation. Using the above mechanisms and their models they have studied the influences of a micro-oscillation on contact resistance. In this paper, first, it was shown that there was a degradation phenomenon of electrical contacts by experimental results using micro-sliding mechanism (MSM). And it was also shown that the phenomenon was depended on contact frictional force between a male-pin and a female-pin of a connector and sliding stroke. Second, it was made clear that there was the parallel degradation phenomenon of electrical contacts by experimental results using hammering oscillating mechanism (HOM). And the phenomenon was depended on the above contact frictional force and impulsive acceleration generated by a hammering ball. Finally, by comparing the above experimental results, the authors obtained that the similarity between two types of phenomena came from similar mechanical parameters like amplitude, natural frequency and damping ratio which characterized time-sequential relative displacement on an electrical contact, though the mechanism was quite different from each other, as the former by sliding and the latter by hammering. And they recognized that phenomena occurred more frequently in actual static contacts under the influence of some oscillation or vibration.