An air purifier includes: a housing; a fan in the housing; an outlet in a top face of the housing, air being blown out via the outlet; an air passage spatially connecting the fan to the outlet; and an illumination unit configured to illuminate the air passage, wherein the air passage includes an upstream, first air passage and a downstream, second air passage, the first air passage extends upwards, the second air passage has a curved surface or an inclined surface inclined with respect to the first air passage, and the illumination unit illuminates the curved surface or the inclined surface.

A filter element for a filter system for filtering a fluid has a filter bellows arranged about a longitudinal axis and enclosing an interior of the filter element. A closed end disk is arranged at a first end of the filter element and closes off the interior of the filter element. An end disk with an opening to the interior of the filter element is arranged at a second end of the filter element oppositely positioned to the first end viewed in direction of the longitudinal axis. The closed end disk has a hollow pin projecting into the interior of the filter element in direction of the longitudinal axis. The filter system has a housing for receiving the exchangeable filter element with a housing part closable by a cover. The hollow pin of the closed end disk can be pushed onto a pin of the housing part.

A diffuser includes a first tube and a second tube. The first tube includes a key and defines a first opening. The second tube is inserted through the first opening. The second tube defines a notch. The key is inserted into the notch.

An air purifying unit in which leakage of air flowing between a filter and a blowing fan is significantly reduced, and an air cleaning/ventilation device including the same, are provided. In addition, there are an air cleaning/ventilation device detachably installed in a window, used as a ventilation device, and used as an indoor air cleaning device.

There is provided an air cleaner including: an outlet pipe through which air is discharged; an airflow meter that is inserted toward an interior of the outlet pipe through a wall of the outlet pipe; and a flow-regulating member that is formed projecting from an inner surface of the outlet pipe at a leading end side of the airflow meter, the flow-regulating member including an edge that is formed with a peaked shape with respect to the inner surface and that runs along a direction of flow of air, a rear end that is formed at a downstream end of the edge in the direction of flow, and that is shaped cut sharply toward the inner surface and a width-narrowing portion that decreases in width in a circumferential direction of the outlet pipe on progression downstream in the direction of flow.

An air filtration system includes a filtration device having a filter element and a blower, a dispersion casing defining an internal cavity having an inlet fluidly coupled to the blower of the filtration device and an outlet leading to the ambient environment, a duct fluidly coupling the blower of the filtration device to the inlet of the dispersion casing, and a flow reducing feature configured to cause the flow of air to have a reduced flow velocity at the outlet of the dispersion casing in comparison to the inlet of the dispersion casing.

One illustrative system disclosed herein includes an upper filter, a lower filter positioned vertically below the upper filter, at least one incoming air inlet positioned vertically above the upper filter, and a vacuum pump positioned vertically below the lower filter, the vacuum pump comprising an outlet, wherein an incoming air stream is adapted to flow downwardly through the at least one incoming air inlet, then through the upper filter, then through the lower filter and then out of the outlet of the vacuum pump where it exits as a cleaned air stream.

An air flow controller for an air cleaner and an air cleaner are provided. The air flow controller may include a fan, and a housing, the fan being provided in the housing and the housing being movable from an initial horizontal position in which the air flow controller directs air flow in a vertical direction to an inclined position in which the air flow controller directs air flow in a diagonal direction.

An air cleaner is provided that may include at least one blowing device including a main fan that generates air flow and a first discharge outlet through which air passing through the main fan is discharged; a flow controller movably provided at one side of the at least one blowing device, the flow controller including a sub-fan that generates air flow and a discharge grill through which air passing through the sub-fan is discharged; and a display provided in the discharge grill, the display device displaying operation information.

An inlet barrier filter system for a tiltrotor aircraft comprising a filter duct extending from a filter to a filter outlet, a ram air duct extending from a ram air inlet to an engine where the filter duct connects to the ram air duct at the filter outlet, and a closure member movable between a first position blocking the ram air duct and a second position blocking the filter outlet. In use, the inlet barrier filter system provides for two mutually exclusive air flow paths, one for introducing ram air to the engine while closing off the filter and another air flow path for introducing filtered air to the engine while closing off the ram air duct.