Fiber brush slip ring assembly

A slip ring and brush assembly for transmitting electrical energy between a stationary conductor and a rotating shaft, the assembly comprising:

• a gold plated slip ring surface on the rotating shaft,
• a fiber brush in contact with said gold plated slip ring surface and coupled to the stationary conductor, the fibers of said brush each being from 1 to 3 mils in diameter and being maintained in a bundle of between 20 and 10,000 fibers by a collar located on said bundle at a point spaced from the fiber ends,
• a brush holder for maintaining said fiber brush in contact with said gold plated slip ring, said brush holder biasing said brush against said slip ring surface,
• said gold plated slip ring surface having a hardness which is less than the hardness of the fibers of said brush, whereby during use gold is transferred from the gold plated slip ring surface to the regions of the fibers in actual contact with the slip ring, whereby said slip ring and brush assembly will withstand at least 20 million inches of ring travel and is capable of transmitting current in excess of 7,000 amps per square inch without lubrication between ring and brush.