| 摘要 |
A contact arrangement consisting essentially of copper or of a copper alloy, for load selectors of stepping transformers, having at least one cylindrical contact roller which is guided in a moving contact carrier and can roll off along a predetermined rolling track on the essentially flat surface of a stationary contact piece. In this case, at least one annular thin layer of silver is provided on the outer surface of the contact roller, which layer projects slightly with respect to the outer surface. Furthermore, a partial, likewise thin, silver layer is provided on the surface of the stationary contact, approximately in the centre on the track running through from the annular silver layer of the contact roller, of such a surface extent that, in the quiescent position of the contact arrangement, the annular silver layer of the contact roller comes to rest on the partial silver layer of the surface of the stationary contact. |
