In an air cleaner (32), three cyclone dust collection units (34) are arranged on one side of a filter dust collection unit (35) in a mutually parallel relationship. The cyclone dust collection units are arranged along a circumferential direction of the filter dust collection unit, and the central cyclone dust collection unit has a smaller diameter than the remaining cyclone dust collection units positioned on either side of the central cyclone dust collection unit so that the dust collection units can be accommodated in a rectangular profile is a highly space efficient manner.

A cyclone filtering device includes first and second filters. The first filter includes a first filtering tube defining a first turbulence room, and has a coupling cover communicated with the first turbulence room and disposed for allowing passage of fluid, and a barrel seat defining a dust collecting room that is communicated with the first turbulence room. The second filter includes a second filtering tube defining a second turbulence room that is communicated with the first turbulence room, two end covers having an end opening that is communicated with the second turbulence room, and a capture member disposed in the second turbulence room and disposed for capturing substances that are entrained in the fluid.

A cyclone filtering device includes first and second filters. The first filter includes a first filtering tube defining a first turbulence room, and has a coupling cover communicated with the first turbulence room and disposed for allowing passage of fluid, and a barrel seat defining a dust collecting room that is communicated with the first turbulence room. The second filter includes a second filtering tube defining a second turbulence room that is communicated with the first turbulence room, two end covers having an end opening that is communicated with the second turbulence room, and a capture member disposed in the second turbulence room and disposed for capturing substances that are entrained in the fluid.

The dust collector, that may be used in vacuum cleaner, includes: a primary cyclone unit separating dust from air introduced from outside the dust collector; and a secondary cyclone unit defining axial cyclone bodies separating fine dust from air introduced in an axial direction. The secondary cyclone unit includes casings having outer walls around hollow portions; and a fine dust separating member disposed on the casings to form the axial cyclones. The fine dust separating member includes vortex finders disposed in the casings; band portions enclosing an outer circumferential surface of the vortex finders at a position spaced from the vortex finders, and having a shape corresponding to the casings so as to form the axial cyclones together with the casings; and guide vanes disposed between the vortex finders and the band portions and extending in a spiral direction to induce a rotational flow of air.

The dust collector, that may be used in vacuum cleaner, includes: a primary cyclone unit separating dust from air introduced from outside the dust collector; and a secondary cyclone unit defining axial cyclone bodies separating fine dust from air introduced in an axial direction. The secondary cyclone unit includes casings having outer walls around hollow portions; and a fine dust separating member disposed on the casings to form the axial cyclones. The fine dust separating member includes vortex finders disposed in the casings; band portions enclosing an outer circumferential surface of the vortex finders at a position spaced from the vortex finders, and having a shape corresponding to the casings so as to form the axial cyclones together with the casings; and guide vanes disposed between the vortex finders and the band portions and extending in a spiral direction to induce a rotational flow of air.

A dust collector includes a primary cyclone unit to separate dust from air introduced from outside dust collector and a secondary cyclone unit includes axial cyclones which separate fine dust from air introduced in an axial direction. The secondary cyclone unit includes a first group of axial cyclones disposed along a circumference of a first circle so as to contact an inner circumferential surface of an inner case, and formed to be partially spaced apart from the inner circumferential surface of the inner case to form first passages therebetween; and a second group of axial cyclones disposed to contact each other along a circumference of a second circle concentric with the first circle and smaller than the first circle, and formed to contact some of the first group of axial cyclones and to be spaced apart from others of the first group axial cyclones to form second passages therebetween.

A dust collector includes a primary cyclone unit to separate dust from air introduced from outside dust collector and a secondary cyclone unit includes axial cyclones which separate fine dust from air introduced in an axial direction. The secondary cyclone unit includes a first group of axial cyclones disposed along a circumference of a first circle so as to contact an inner circumferential surface of an inner case, and formed to be partially spaced apart from the inner circumferential surface of the inner case to form first passages therebetween; and a second group of axial cyclones disposed to contact each other along a circumference of a second circle concentric with the first circle and smaller than the first circle, and formed to contact some of the first group of axial cyclones and to be spaced apart from others of the first group axial cyclones to form second passages therebetween.

A dust collector includes a cylindrical housing forming an outer appearance of the dust collector; a cyclone inside the housing to cause a swirling flow to separate dust from air introduced into the housing; axial inlet type swirl tubes receiving air and fine dust that have passed through the cyclone, and causing a swirling flow to separate the fine dust from the air; and a mesh surrounding an outside of the axial inlet type swirl tubes to form a boundary between the cyclone and the axial inlet type swirl tubes, wherein the axial inlet type swirl tubes are stacked in stages and the axial inlet type swirl tubes in each stage are arranged in first and second columns that are provided in opposite directions to each other, and axial lengths of the axial inlet type swirl tubes gradually increase toward the center of each stage.

A dust collector includes a cylindrical housing forming an outer appearance of the dust collector; a cyclone inside the housing to cause a swirling flow to separate dust from air introduced into the housing; axial inlet type swirl tubes receiving air and fine dust that have passed through the cyclone, and causing a swirling flow to separate the fine dust from the air; and a mesh surrounding an outside of the axial inlet type swirl tubes to form a boundary between the cyclone and the axial inlet type swirl tubes, wherein the axial inlet type swirl tubes are stacked in stages and the axial inlet type swirl tubes in each stage are arranged in first and second columns that are provided in opposite directions to each other, and axial lengths of the axial inlet type swirl tubes gradually increase toward the center of each stage.

A dust collector includes a cylindrical housing forming an outer appearance of the dust collector; a cyclone formed inside the housing to cause a swirling flow to separate dust from air introduced into the housing; axial inlet type swirl tubes to receive air and fine dust that have passed through the cyclone, and causing a swirling flow to separate the fine dust from the air; and a mesh configured to surround an outside of the axial inlet type swirl tubes to form a boundary between the cyclone and the axial inlet type swirl tubes, wherein the axial inlet type swirl tubes are configured with four groups and stacked in multiple stages on virtual quadrants, the axial inlet type swirl tubes arranged in the same quadrant are arranged to face the same direction, and the axial inlet type swirl tubes arranged in different quadrants are arranged to face different directions.