Patent attributes
A vortex finder (18,27,40) for a cyclonic separator (1) through which air flowing in a helical path ‘D’ about an axis A-A of a cyclone chamber (4) passes to an outlet (6) is disclosed. The vortex finder comprises a plurality of stationary overlapping vanes (13,19) extending in an axial direction and spaced radially around said axis ‘A’, the vanes (13,19) being positioned relative to each other so a helical flow of air about the axis of the cyclone chamber (4) passes over an outer surface (16) of the vanes (13,19) with a portion of the air flow being redirected around a leading edge (14) of each vane (13,19) and through a gap between adjacent vanes (13,19) to the outlet (6). At any point along the axis, a portion of an outer surface (16,20,30,46) of each vane (13,19,28,41) lies on a circle having its center coaxial with said axis, the outer surface (16,20,30,46) of each vane (13,19,28,41) having a portion leading towards the leading edge (14,33,47) that extends inwardly away from the circle so that the leading edge (14,33,47) of each vane (13,19,28,41) about which air is redirected through the gap between vanes (13,19,28,41) is located within a region bound by said circle to create a region of overpressure on the outer surface (16) of the adjacent vane (13,19) in the vicinity of the gap.
