Abstract: Dynamoelectric machines are disclosed that are characterized by lengthened ground potential leakage current paths, desirable mechanical conformations, mechanical integrity when subjected to expected centrifugal forces, and ease of manufacture. One process involves establishing an extended or elongated path for commutator leakage currents with a path extending structure, establishing a cantilevered insulation skirt about the in-board or armature coil end of a commutator, and securely fastening such skirt to the commutator. The material utilized in making the skirt is one: that has electrical properties that permit it to withstand leakage currents without tracking; that for practical purposes is non-burnable, so as to resist flashovers or sparking; and that has the ability to withstand elevated temperatures that are encountered within dynamoelectric machine.

Abstract: Dynamoelectric machines characterized by lengthened ground potential leakage current paths, desirable mechanical conformations, mechanical integrity when subjected to expected centrifugal forces, and ease of manufacture. One process involves establishing an extended path for commutator leakage currents with a path extending structure, establishing a cantilevered insulation skirt about the in-board or armature coil end of a commutator, and securely fastening such skirt to the commutator. The material utilized in making the skirt is one: that has electrical properties that permit it to withstand leakage currents without tracking; that for practical purposes is non-burnable, so as to resist flashovers or sparking; and that has the ability to withstand elevated temperatures that are encountered within dynamoelectric machine. The skirt is provided with openings therein and sandwiched between two glass based bands that adhere to another through the openings and thus lock the skirt in place on the commutator body.