Rotatable bus rings for collectors

Claim 1

An improved dynamoelectric machine of the type used to generate electrical current in response to a rotating field, including a rotor having an electrically conductive, continuous collector ring rotatable therewith; an electrically conductive bus ring adjacent said collector ring including a plurality of removable, electrically conductive, brushes having the same polarity radially depending from said bus ring in sliding electrical contact with said collector ring; a direct current power supply connected to said bus ring; and, said collector ring of the type wherein the brushes may be circumferentially moved about the collector ring without changing said dynamoelectric machine characteristics; the improvement comprising: means for rotatably supporting said bus ring adjacent said collector ring; means for turning said bus ring about its own axis whereby portions of the bus ring heretofore inaccessible are rendered accessible for brush mounting and servicing; and means for providing continuous electric contact between said bus ring and said power supply even while said bus ring is being serviced.