Abstract: A vacuum cleaner uses a special self-cleaning filter arrangement including an initial fabric filter having a relatively large mesh size with a broad open mesh ratio of 5 to 11 flat filter threads 0.025 to 0.045 inches in width defining oblong filter openings 0.002 to 0.006 inches in width between longitudinal strands having substantially flat upstream surfaces and having a length between transverse strands not greater than will maintain the structural integrity of the filter openings and a total opening area of 5 to 45 times the cross section of the inlet, which inlet faces away from the filter. The initial filter is preferably backed up by secondary filters which filter particulates passing through the initial fabric filter especially during startup and while the filter cleans itself. Various elements for strengthening the longitudinal strands to maintain the structural integrity of the filter medium with relatively long or extended filter openings are provided.

Abstract: A vacuum cleaner uses a special self-cleaning filter arrangement including an initial fabric filter having a relatively large mesh size with a broad open mesh ratio of 5 to 11 flat filter threads 0.025 to 0.045 inches in width defining oblong filter openings 0.002 to 0.006 inches in width and having a length not greater than will maintain the structural integrity of the filter openings and a total opening area of 5 to 45 times the cross section of the inlet, which inlet faces away from the filter. The initial filter is preferably backed up by secondary filters which filter particulates passing through the initial fabric filter especially during startup and while the filter cleans itself.

Abstract: A vacuum cleaner uses a special self-cleaning filter arrangement including an initial fabric filter having a relatively large mesh size with a broad open mesh ratio of 5 to 15% and a total opening area of 5 to 45 times the cross section of the inlet, which inlet faces away from the filter. The initial filter is preferably backed up by secondary filters and is arranged so that dirt collected on the filter is periodically sloughed off and dropped into a receptacle after building to a critical level.

Abstract: A portable apparatus for blowing a chemically treated cellulose insulating material into an attic, wall cavity or wet spraying the material against a surface for insulating it. The apparatus breaks the cellulose material into small particles and, after fluffing the material, the apparatus meters and feeds the material under pressure through a hose and out through a nozzle where an operator can point the nozzle for directing the material to any desired area. Three different nozzles are used: one for attic insulation; a second for filling wall cavities; and a third for wet spraying the material against a surface for causing the material to adhere to the surface.