Patent ID: 8097070

Claim:
A forced air open-ventilation system for an electrical machine structured to have air channeled therethrough, the forced air open-ventilation system comprising: air forcing means for creating a high-velocity outlet stream, the air forcing means disposed downstream of the electrical machine; an air cleaner having an air chamber and a rotating means, the air chamber having at least an outer wall, at least one inlet through which air is drawn in from the surroundings by the air forcing means of the open-ventilation system, at least one first outlet through which air that is substantially particle free is drawn out of the air chamber by the air forcing means, at least one second outlet through which air is drawn out of the air chamber by the high-velocity outlet stream of the open-ventilation system, and, the rotating means contained within the air chamber and drivable to rotate about an axis to subject the air within the air chamber to a centrifugal force such that any particles within the air chamber are thrown radially outwardly towards the at least one second outlet; a filter adapted to remove from the air any particles not removed from the air chamber via the at least one second outlet, the filter disposed downstream of the air chamber; an outlet through which the high-velocity outlet stream is ejected from the open-ventilation system; wherein the at least one air chamber first outlet is formed at or near the axis of the rotating means; wherein the at least one air chamber second outlet has an upstream end that is formed in the outer wall of the air chamber adjacent to the radially outer edge of the rotating means and a downstream end that leads to a portion of the open-ventilation system that is located after the air forcing means but before the outlet; and wherein the air forcing means of the open-ventilation system is located at or near the outlet but before the downstream end of the at least one second outlet such that the effect of the high-velocity outlet stream passing the downstream end of the at least one air chamber second outlet creates a pressure differential across the length of the at least one second outlet which results in air and any particles within the air chamber that have been thrown radially outwardly towards the at least one second outlet by the rotating means being drawn out of the air chamber through the at least one air chamber second outlet and into the high-velocity outlet stream to be ejected through the outlet.