Abstract: A filter bed for an air cleaner, or the like, comprising a compressed mass of coils each having axially spaced portions of different diameters. With this construction, the tendency of the coils to nest together over their entire lengths is reduced, and the filtering ability of the bed is increased.

Abstract: An air cleaner of the oil-bath type, in which dust-laden air at high velocity in a stream entering the unit is first mixed with an oil spray and then impinged on an oil washed deflector for directing the mixture outwardly and upwardly through a filter bed to wet the filter bed with oil for catching dust carried by the air, surplus oil being drawn by venturi action from the filter bed and sprayed back into the entry stream for recirculation into the filter bed, and the air cleaner having a dual-chamber oil reservoir and dust collecting means, a novel venturi means, and a mechanical agitator in the air inlet to prevent the accumulation of dust therein.

Abstract: An air cleaner of the oil-bath type, in which dust-laden air at high velocity in an entry stream is first mixed with an oil spray and then impinged on an oil bath and deflected outwardly and upwardly through a filter bed to wet the filter bed with oil for catching dust carried by the air, surplus oil being drawn by venturi action from the filter bed and sprayed back into the entry stream for recirculation into the oil bath and into the filter bed, constantly washing the lower end of the filter bed and other parts so as to prevent clogging by the accumulation of dust.