Abstract: A heat exchanger for heating cleaning liquid with exhaust gasses from an internal combustion engine that have been treated by a catalytic converter further includes an arrangement for injecting fuel into the gases to further provide heat in the exchanger.

Abstract: A mobile cleaning system in which an extraction blower is driven by a hydraulic circuit including a pump driven by the engine of the transport vehicle and a motor connected to the blower. The improvement comprises a heat exchanger for transferring heat from the hydraulic circuit to liquid extracted by the vacuum created by the blower.

Abstract: The vacuum nozzles in a rotary surface cleaning appliance are skewed with respect to the path of travel of the nozzles to enable the nozzles to glide smoothly over the surface being cleaned. A flexible mount for each nozzle on a rigid, radial vacuum duct permits the nozzle to accommodate irregular and different textured surfaces being cleaned.

Abstract: A drive system for a surface cleaning appliance having a pair of rotatable head structures employs a worm gear positioned between the head structure in engagement with two spur gears on, respectively, the two head structures.

Abstract: A hood with a depending side wall has vacuum passages formed in the inner surface thereof. An inner shroud positioned internally of the hood cooperates therewith in forming the vacuum passages and has a lower edge elevated above the surface to be cleaned. A foramenous skirt depends from the lower edge of the hood sidewall to contact the surface to be cleaned. The vacuum passages are connected to a source of vacuum. A rotating spray assembly inside the shroud sprays cleaning liquid onto the surface to be cleaned.

Abstract: The vacuum extractor of the present invention is a self contained system for delivery of hot cleaning solution to a surface and vacuum removal of the spent solution either simultaneous with its application or at a later time through a vacuum system which deposits the spent cleaning solution in an upper housing. The extractor is configured to dump the cleaning solution from an upper housing which may be pivotally tipped upwardly from the front to enhance the draining of spent solution. The rear of the extractor of the present invention is configured to enable the extractor to be back up to and located adjacent a toilet bowl. The upper housing containing the spent solution is high enough to be pivoted over the toilet bowl and emptied, while still pivotally attached to the lower housing. The dump valve is positioned to be protected from damage from bumping surrounding structure.

Abstract: A cleaning system utilizes heat from an internal combustion engine to heat cleaning liquid which is sprayed onto a surface to be cleaned. The internal combustion engine drives a vacuum pump which withdraws air and cleaning liquid through a vacuum nozzle for retrieving cleaning liquid and soil. The heated air leaving a vacuum pump is combined with heated exhaust gasses from said engine and heat from the mixture is extracted to heat the cleaning liquid. The cleaning liquid may be further heated by heat extracted from the engine by a cooling system.

Abstract: A cleaning system includes a liquid heating system utilizing heat from the cooling air and the exhaust gases of an internal combustion engine. A heat pump driven by the engine is utilized to extract heat from the cooling air and impart that heat to a first heat exchanger. A second heat exchanger is associated with the exhaust gases for extracting heat therefrom. Liquid to be heated is conveyed through said first and second heat exchangers.

Abstract: Multiple side-by-side vacuum nozzles are reciprocated along paths of travel parallel to the preferred path of travel of carpet cleaning apparatus. The vacuum nozzles are propelled through a drive mechanism which moves each vacuum nozzle out of phase with the movement of every other nozzle. Cleaning fluid discharge members associated and movable with each vacuum nozzle direct cleaning fluid onto the carpet adjacent their respective vacuum nozzles.

Abstract: A hood with a depending side wall has vacuum passages formed in the inner surface thereof. An inner shroud positioned internally of the hood cooperates therewith in forming the vacuum passages and has a lower edge elevated above the surface to be cleaned. A foramenous skirt depends from the lower edge of the hood sidewall to contact the surface to be cleaned. The vacuum passages are connected to a source of vacuum. A rotating spray assembly inside the shroud sprays cleaning liquid onto the surface to be cleaned.