A two-stage dust-air separation structure includes a cyclone separator and a spiral dust-air separation device. A first stage separation of dust from air is realized by a cyclone housing, and by arranging a second-stage cyclone barrel 5 inside the cyclone housing and arranging the spiral dust-air separation device at a barrel opening of the second-stage cyclone barrel, the dusty air, after going through the first stage separation, is guided by the spiral dust-air separation device to form, on an inner wall of the second-stage cyclone barrel, an airflow rotating towards the barrel bottom, and the dust in the airflow is driven by a centrifugal force to rotate downwardly to the barrel bottom and be collected in a second-stage dust collecting space, and the air in the rotating airflow is extracted by the negative pressure, thereby realizing a second stage separation of dust from air.

Air cleaner assemblies, components therefor, and features thereof are described. Also described are methods of assembly and use. In depicted examples, the air cleaner assemblies and components optionally use advantageous housing seal features. Methods of assembly and use are described.

An air filtration system is described that is suited for CBRN and ColPro applications, and has an integrated inertial particle separator (IPS) and scavenge fan blower as a pre-dust/particle filter, a variable speed fan blower, and a filter housing that mounts two gas-particulate filter sets. The variable speed fan blower, managed by a motor control unit and motor speed algorithm, automatically adjusts its speed to maintain constant air flow regardless of its altitude.

A vacuum cleaner including a dirty air inlet, a fluid flow path extending from the dirty air inlet to a clean air outlet, a fluid flow motor positioned in the fluid flow path, and a filter assembly positioned in the fluid flow path. The filter assembly including a first cylindrical filter and a second cylindrical filter nested within and removable from the first cylindrical filter. An inner diameter of the first cylindrical filter is smaller than an outer diameter of the second cylindrical filter such that the second cylindrical filter is compressed in order to be nested within the first cylindrical filter.

A vacuum cleaner including a dirty air inlet, a fluid flow path extending from the dirty air inlet to a clean air outlet, a fluid flow motor positioned in the fluid flow path, and a filter assembly positioned in the fluid flow path. The filter assembly including a first cylindrical filter and a second cylindrical filter nested within and removable from the first cylindrical filter. An inner diameter of the first cylindrical filter is smaller than an outer diameter of the second cylindrical filter such that the second cylindrical filter is compressed in order to be nested within the first cylindrical filter.

An air pre-cleaner spin tube includes a vaned inlet section including an inlet flange, and an outer tube inlet portion including an outer wall forming a nozzle that defines a radial direction, and a longitudinal axis. Also, a central stem is disposed in the nozzle, and a plurality of vanes extends from the central stem to the outer wall.

Air cleaner and preferred components for an air cleaner are provided. In certain arrangements, a band is mounted to the media pack, surrounding the media. Also, the cartridge is non-circular and includes a seal thereon.

Air cleaner and preferred components for an air cleaner are provided. In certain arrangements, a band is mounted to the media pack, surrounding the media. Also, the cartridge is non-circular and includes a seal thereon.

In a method for operating a surface treatment installation, overspray produced in a coating booth is taken up by an air stream and carried to one or more one-way filter modules, in which overspray is separated. Once a limit loading with overspray is reached, a one-way filter module is exchanged for an empty one-way filter module. Depending on the nature and characteristics of the overspray, the one or more one-way filter module(s) may be chosen from a set of different one-way filter modules. A set of filter modules for use in a surface treatment installation is provided having various filter modules formed as exchangeable one-way structural units with a module housing and a filter unit. The module housings of the various filter modules have the same-connection module inlets and the same-connection module outlets and at least the filter units of two different filter modules are formed differently.

A hand vacuum cleaner has an upper end, a lower end, an air flow passage, a main body with a handle, an air treatment chamber and a suction motor. The air treatment chamber has an air outlet, the air outlet comprising a rigid porous member and a filter media that is removably positionable in the rigid porous member. The air treatment chamber is moveable to an open position in which the air treatment chamber is emptyable, and the rigid porous member is moveable within the air treatment chamber to an open position in which the filter media is removable.