GB754025A - Improvements relating to filter bags for suction cleaners - Google Patents

Abstract

754,025. Suction cleaner filter bags. HOOVER, Ltd. May 26, 1954 [May 28, 1953 ; May 28, 1953], No. 15556/54. Class 8(2). [Also in Groups VIII and XVII] The neck 23, Fig. 1, of a suction cleaner filter bag 22 comprising a tubular body of porous paper has thin-walled thermoplastic tubes 31, 32, Fig. 3, bonded to it on both the inside and outside e.g. by the application of heat and pressure. The body is so pleated throughout its length that when the neck 23 is gathered round the inner tube 31 the inner and outer fold lines 29, 30 at the edges of the upper and lower webs are spaced slightly apart and the tubes 31, 32 project outwardly from the neck and are themselves bonded together. The other end of tube 31 projects into the bag to provide a dirt trap and the unbonded end of the outer tube 32 serves as a resilient girdle to protect the inflated bag during bending. The bonded ends of the tubes are cut obliquely at 53 to assist sliding over an adapter tube 21 connected by a flexible bellows 20 to the cleaner exhaust duct 17. In a modification the outer plastic tube 74, Fig. 8 forms the flexible connection between the pleated filter bag 59 and a rigid adapter tube 60 locked to the exhaust duct 11 or made integral therewith. The overlapping ends of tubes 60, 74 are cut obliquely at 80, 76 and a notch registers with a locating boss on the outside of the adapter tube 60.