An apparatus for separating particles from an airflow, the apparatus comprising a housing comprising an inner wall, and a body positioned within the housing and separated therefrom so as to define a substantially annular flow path between the body and the inner wall. The housing is rotationally stationary, and the body is rotatable relative to the housing about a rotational axis, the body comprising an impeller section having a first set of blades extending from the body into the annular flow path towards the inner wall of the housing, the impeller being rotatable for generating airflow through the apparatus and for generating swirl within the airflow, and a turbine section located downstream of the impeller section, the turbine section having a second set of blades for recapturing rotational energy from the airflow.

A surface cleaning apparatus has a first air flow path extending from a dirty air inlet to a clean air outlet with a suction motor and a cyclone positioned in the first air flow path. The cyclone has a cyclone chamber, a first airflow passage, and a second airflow passage. The first airflow passage defines a first tangential air inlet to the cyclone chamber and the second airflow passage defines a second tangential air inlet to the cyclone chamber. The airflow path includes a common airflow passage upstream of the first and second airflow passages and an axis of the common airflow passage intersects the cyclone chamber. At least a portion of the first tangential air inlet is positioned upstream from a location at which the common airflow passage axis intersects the cyclone chamber.

A surface cleaning apparatus has a first air flow path extending from a dirty air inlet to a clean air outlet with a suction motor and a cyclone positioned in the first air flow path. The cyclone has a cyclone chamber, a first airflow passage, and a second airflow passage. The first airflow passage and second airflow passage are isolated from each other. The first airflow passage defines a first tangential air inlet to the cyclone chamber and the second airflow passage defines a second tangential air inlet to the cyclone chamber. The second tangential air inlet is positioned around the perimeter of the cyclone chamber sidewall downstream from the first tangential air inlet in the direction of rotation of air in the cyclone chamber.

A cyclone separator useable in a surface cleaning apparatus comprises a cyclone chamber and a dirt collection chamber exterior to, and surrounding at least a portion of the cyclone chamber. The dirt collection chamber is in communication with the cyclone chamber via a dirt outlet. An air flow passage extending to the cyclone air inlet travels generally axially through the dirt collection chamber.

A vacuum cleaner has a housing and a cover moveably mounted to the housing between a closed position and an open position. A filter is carried by the cover and includes an upstream surface and a downstream surface through which working air passes. When a user of the vacuum cleaner opens the cover, the upstream surface of the filter can be seen by the user.

The invention relates to a dust-handling device (1) for collecting and handling dust in a paper-making environment wherein the dust-handling device (1) comprises a source of underpressure (2) and an elongated collector (3) that extends along a longitudinal axis. The elongated collector (3) is connected to the source of underpressure (2) such that underpressure can be generated inside the elongated collector (3) and the elongated collector (3) has an inlet (5) through which dust-laden air can enter the elongated collector (3) and an exit opening (6) through which dust-laden air can be evacuated from the elongated collector. The inlet (5) of the elongated collector (3) is disposed in such a relation to the longitudinal axis of the elongated collector (3) so that upon drawing the dust-laden air into the elongated collector (3), an air vortex is induced with the dust-laden air wherein the induced air vortex flows between the collector inlet (5) and the collector exit opening (6). A source of water (7) is connected to the elongated collector such that water can be introduced into elongated collector (3) so that dust of the dust-laden air can be exposed to and mix with the water introduced into the elongated collector (3). According to the invention, a dust removal device (8, 10) is mounted on the elongated collector and arranged to act against the inlet (5) to remove dust that has clogged the inlet (5).The invention also relates to a method in which dust clogging the inlet (5) is removed.

A cyclone separator useable in a surface cleaning apparatus comprises a cyclone casing defining a cyclone chamber and having first and second opposed ends and a sidewall extending between the first and second ends. A separated material collection chamber surrounds at least a portion of the cyclone chamber and is communication therewith via a separated material outlet. The separated material collection chamber is spaced at least about 0.5 inches from the cyclone chamber. In addition, the separated material collection chamber is spaced from the bottom of the cyclone by at least about 0.5 inches.

A vacuum cleaner includes a cyclone separator, a collection chamber below the cyclone separator, a pre-motor filter downstream from the cyclone separator, and an openable cover above the pre-motor filter. The cover provides access to an upstream surface of the pre-motor filter when open, and forms an outer surface of the vacuum cleaner that is angled forwardly at an incline.

A vacuum cleaner has a housing and a cover moveably mounted to the housing between a closed position and an open position. A filter is carried by the cover and includes an upstream surface and a downstream surface through which working air passes. When a user of the vacuum cleaner opens the cover, the upstream surface of the filter can be seen by the user.

A vacuum cleaner includes a cyclone separator, a collection chamber below the cyclone separator, a pre-motor filter downstream from the cyclone separator, and an openable cover above the pre-motor filter. The cover provides access to an upstream surface of the pre-motor filter when open, and forms an outer surface of the vacuum cleaner that is angled forwardly at an incline.