Cyclonic separation device

A cyclonic separator comprising a separation device, wherein the separation device comprises:

• a cyclone chamber having a leading end and a trailing end;
• a collection chamber;
• and
• a guide surface for guiding debris entrained in an airflow in the cyclone chamber in a helical path about a central axis of the separation device and into the collection chamber,
• wherein the guide surface extends continuously about the central axis of the separation device to a first angle from the leading end to the trailing end of between 270 degrees and 340 degrees defining a flow path for allowing debris in the cyclone chamber to also pass into the collection chamber from the cyclone chamber in an axial direction of the separation device,
• wherein the guide surface is angled towards the cyclone chamber with respect to the central axis of the separation device such that the guide surface is sloped along a longitudinal direction of the separation device forming an angle a between the guide surface and the central axis of the separation device that continuously increases about the central axis of the separation device in a direction from the leading end to the trailing end, and
• wherein the angle α at the leading end has a first value α1 between 30 degrees and 60 degrees and the angle α at the trailing end has a second value α2 greater than the first value α1.

A vacuum cleaner comprising a cyclonic separator having a separation device, a cyclone chamber and a collection chamber, wherein the separation device comprises:

• a leading end;
• a trailing end;
• and
• a guide surface for guiding debris entrained in an airflow in the cyclone chamber in a helical path about a central axis of the separation device and into the collection chamber,
• wherein the guide surface extends continuously about the central axis of the separation device to a first angle from the leading end to the trailing end of between 270 degrees and 340 degrees defining a flow path for allowing debris in the cyclone chamber to also pass into the collection chamber from the cyclone chamber in an axial direction of the separation device,
• wherein the guide surface is angled towards the cyclone chamber with respect to the central axis of the separation device such that the guide surface is sloped along a longitudinal direction of the separation device forming an angle a between the guide surface and the central axis of the separation device that continuously increases about the central axis of the separation device in a direction from the leading end to the trailing end, and
• wherein the angle α at the leading end has a first value α1 between 30 degrees and 60 degrees and the angle α at the trailing end has a second value α2 greater than the first value α1.