Abstract: A portable air cleaner comprising a cylindrical filter element mounted on a circular base and encased by a cylindrical cover. A centrifugal fan mounted within the cover draws unpurified air into inlet openings disposed in the base and the side wall of the cover, and through the filter element. The resulting purified air is drawn into the centrifugal fan and forced radially outward therefrom. An air deflector dish redirects the purified air through the exhaust openings disposed on the top surface of the cylindrical cover. Such an exhaust flow which is perpendicular to and spaced from the inlet flow results in an improved efficiency in purifying the entire volume of air within a room.

Abstract: An appliance includes a housing defining an air inlet and an air outlet facing opposite to the air inlet, an inlet detector for detecting objects in an inlet zone projecting away from the inlet and an outlet detector for detecting objects in an outlet zone projecting away from the outlet. Also included is a control for deactivating the appliance in response to detection of objects in either of the inlet or outlet zones.

Abstract: A portable humidifier having a base defining a boiler cavity; an evaporation mechanism for inducing evaporation of liquid within the boiler cavity; and a liquid supply including a contractible and expandible vessel having an outlet communicating with the boiler cavity and providing restricted liquid flow between the vessel and the cavity.

Abstract: This invention relates to a filter change indicator that is operable in various orientations of the device incorporating it. For example, the filter change indicator is operable when the device is positioned in either the upright or sideways position. The device incorporating the filter change indicator can be any air moving device which incorporates a cleanable or replaceable filter. The filter change indicator includes a transparent viewing window and a tubulation. The viewing window displays a visible signal when the filter needs changing. The visible signal can be a float retained in the tubulation. The tubulation is a hollow transparent tube which forms an incline plane within the housing. The tubulation includes a first end, a second end and a step. The first end is in fluid communication with an air flow path through the tubulation, and this air flow path is exposed to atmospheric pressure.

Abstract: A centrifugal blower wheel having an indivisible prime number of peripherally spaced blades projecting upwardly from the top surface of a generally annular-shaped base plate. Each blade includes a tapered portion extending along an inside edge of the blade to approximately 1/3 to 1/2 the length of the blade. A hub is centrally located on the top surface of the base plate and surrounded by the inside edges of the blades, the hub curving upwardly from the top surface of the base plate to form a smoothly contoured curve.

Abstract: This invention relates to a filter change indicator that is operable in various orientations of the device incorporating it. For example, the filter change indicator is operable when the device is positioned in either the upright or sideways position. The device incorporating the filter change indicator can be any air moving device which incorporates a cleanable or replaceable filter. The filter change indicator includes a transparent viewing window and a tubulation. The viewing window displays a visible signal when the filter needs changing. The visible signal can be a float retained in the tubulation. The tubulation is a hollow transparent tube which forms an incline plane within the housing. The tubulation includes a first end, a second end and a step. The first end is in fluid communication with an air flow path through the tubulation, and this air flow path is exposed to atmospheric pressure.