Electrical brush and dynamoelectric apparatus embodying the same

Claim 1

AN ELECTRICAL CONTACT BRUSH SUITABLE FOR OPERATING SATISFACTORILY IN SLIDING CONTACT WITH A FRESHLY DRESSED METALLIC CONDUCTING MEMBER UNDER EXTREME ATMOSPHERIC CONDITIONS, COMPRISING A BODY OF CARBON AND A LAYER DISPOSED ACROSS THE FULL WIDTH OF TH ELEADING SIDE OF THE BRUSH SUBSTANTIALLY AT RIGHT ANGLES TO THE DIRECTION OF RELATIVE SLIDING MOVEMENT OF THE BRUSH TO THE CONDUCTING SURFACE, THE LAYER COMPRISING MOLYBDENUM DISULFIDE IN AN AMOUNT OF AT LEAST 25% OF THE WEIGHT OF TEH LAYER, SAID LAYER COMPRISING A THICK INITIAL OPERATING PORTION DISPOSED AT THE CONTACT SURFACE OF THE BRUSH AND A THIN CONTINUOUS RUNNING PORTION EXTENDING A SUBSTANTIAL DISTANCE BEYOND THE THICK INITIAL OPERATING PORTION, SAID THIN CONTINUOUS RUNNING PORTION BEING SUBSTANTIALLY UNIFORM FROM EDGE TO EDGE OF THE BRUSH AND BEING OF A THICKNESS NOT EXCEEDING 0.08 INCH PER INCH THICKNESS OF TH E BRUSH BETWEEN THE LEADING SIDE AND TRAILING SIDE OF THE BRUSH, THE THICK INITIAL OPERATING PORTION BEING SUBSTANTIALLY UNIFORM FROM EDGE TO EDGE OF THE BRUSH AND BEING OF A THICKNESS OF AT LEAST TWO TO FOUR TIMES THE THICKNESS OF THE CONTINUOUS RUNNING LAYER AND EXTENDING UPWARDLY FROM THE CONTACT SURFACE OF THE BRUSH IN CONTACT WITH THE SLIDNG SUFACE OF THE METALLIC CONDUCTING MEMBER A SUFFICIENT DISTANCE TO PROVIDE ENOUGH MOLYBDENUM DISULFIDE TO LAST UNTIL THE CONTACT SURFACE OF THE METALLIC CONDUCTING MEMBER HAS SO IMPROVED IN ITS COOPERATION WITH THE BRUSH THAT THE THIN CONTINUOUS RUNNING PORTION WILL THEN BE ABLE TO APPLY SUFFICIENT MOLYBDENUM DISULFIDE TO INSURE CONTINUOUS SATISFACTORY OPERATION AT A LOW WEAR RATE OF THE BRUSH.