Apparatus and method of machining brake components

An electric discharge grinding apparatus comprising:

• an electrode assembly including a first plurality of electrodes electrically connected together and a second plurality of electrodes electrically connected together and disposed in a circumferentially spaced apart relationship forming an electrode ring, the electrodes having discharge surfaces circumferentially spaced apart around the electrode ring and aligned in a plane such that each electrode discharge surface forms a separate sector of the electrode ring.

An electric discharge grinding apparatus for machining a part comprising:

• electrodes each having an associated discharge surface, wherein the electrodes are disposed such that the discharge surfaces are aligned in a plane;
• and
• a motor for moving the electrodes during machining such that the electrode discharge surfaces move within the plane, wherein the motor simultaneously moves an electrode near the part to create a spark therebetween while moving another electrode away from the part to prevent a spark therebetween.

An electric discharge grinding apparatus for machining an annular brake rotor friction section comprising:

• electrodes each having an associated discharge surface, wherein the electrodes are disposed such that the discharge surfaces are aligned in a plane;
• and
• a motor for moving the electrodes during machining such that the electrode discharge surfaces move within the plane, wherein the motor simultaneously moves one of the electrodes near the brake rotor friction section to create a spark therebetween while moving another one of the electrodes away from the brake rotor friction section to prevent a spark therebetween.

An electric discharge grinding apparatus for machining a part comprising:

• an electrode ring including circumferentially spaced electrodes having discharge surfaces circumferentially spaced apart around the electrode ring such that each electrode discharge surface forms a separate sector of the electrode ring and the discharge surfaces are aligned in a plane, the electrodes being disposed in electrode groups such that the electrodes within each electrode group are electrically connected to each other and the electrode groups are electrically insulated from each other.