Internally shunting grounding brush assembly with axially-extending conductive fibers

A grounding brush assembly for an electric machine, the electric machine including a rotatable shaft rotatable about a central axis and having an inner circumferential surface defining a hollow bore, an outer housing, at least one bearing rotatably coupling the shaft with the housing, and a fixed shaft extending through the bore of the rotatable shaft and being electrically grounded, the grounding brush assembly comprising:

• an annular inner conductive base member having an annular hub, the hub having a bore sized to receive a portion of the fixed shaft and a centerline coaxially alignable with the central axis, and a radial flange extending radially outwardly from the annular hub;
• an annular outer conductor having an axial portion engageable with the inner circumferential surface of the rotatable shaft so as to couple the outer conductor with the rotatable shaft and a radial flange extending radially inwardly from the axial portion;
• and
• a conductive brush coupled with the conductive base member and including a plurality of conductive fibers extending axially along and circumferentially about the centerline, each conductive fiber having a first axial end coupled with the radial flange of the base member and an opposing second axial end engaged with the radial flange of the outer conductor such that at least one conductive path extends from the rotatable shaft, through the outer conductor, the brush and the base member, and to the fixed shaft.