Patent ID: 6398835
Filing Date: 2002-06-04
Classification: B01D

Abstract:
An air filtering device for removably attaching to a portable electric fan, with the fan including at least a motor casing and a fan guard with a rear portion, a front portion, and a perimeter, said air filtering device comprising:a generally toroidally shaped filter element having a first wall and a second wall opposite said first wall, for removably installing adjacent the rear portion of the fan guard of the fan; said first wall and said second wall respectively having a first opening and a second opening formed centrally therethrough; said first opening and said second opening defining an open inner annulus area between said first wall and said second wall; said filter element further having an outer periphery joining said first wall and said second wall to define a debris capture pocket therebetween, with said debris capture pocket being accessible by means of said open inner annulus area; said first opening of said filter element including means for removably and sealingly attaching to a shroud; said second opening of said filter element including means for removably and sealingly attaching about the motor casing of the fan; and a generally toroidally shaped shroud formed of a particulate impervious material, for removably installing to the perimeter of the fan guard of the fan, said filter element being captured between said shroud and the rear portion of the fan guard of the fan; said shroud having an outer periphery and an inner annular opening; said outer periphery of said shroud including fan guard attachment means extending therefrom; said inner annular opening of said shroud being configured to define a generally toroidally shaped air passage between said inner annular opening of said shroud and the motor casing of the fan; and said inner annular opening of said shroud further including means for removably and sealingly attaching said first opening of said filter element thereto.