Abstract: An electrostatic filter assembly is provided that utilizes electrostatic forces to attract charged particulate matter entrained in a fluid stream to the operating elements in the electrostatic filter assembly and a residual charge between the particulate matter and the electrostatic filter assembly to retain the separated material in the electrostatic filter assembly.

Abstract: A separator for separating entrained particles from a fluid flow incorporates a cyclone chamber having an outer wall and a cyclonic flow region; a fluid inlet for introducing a cyclonic fluid flow to the cyclonic flow region; a fluid outlet for removing the fluid flow from the cyclone chamber; a particle separation member positioned in the cyclone chamber beneath at least a portion of the cyclonic flow region, the particle separation member having an upper surface and plurality of apertures; and a particle receiving chamber disposed beneath the particle separation member for receiving particles passing into the particle receiving chamber through the apertures. In operation, a fluid is introduced to flow cyclonically in a chamber having a cyclonic flow region and a particle separation member positioned in the cyclone chamber to define a particle receiving chamber. The back pressure in the chamber is adjusted to promote the formation of a laminar boundary layer adjacent the particle separation member.

Abstract: A vacuum cleaning head for a vacuum cleaner includes structure for inducing vortices in the incoming air travelling between the sole plate and the surface to be cleaned. The vortices assist in entraining dust and dirt particles raised from the surface to be cleaned by a cleaning implement which may be a brush, beater bar or the like. The axis of the vortices is substantially parallel to the surface to be cleaned and the vortices b ring the rotating air substantially adjacent to and preferably in contact with the surface to be cleaned.