Abstract: A cyclone-type particulate collector and concentrator is provided wherein the outlet tube is provided with a conical concentrator having its sidewalls formed of a plurality of tapered, spaced, nested, generally U-shaped and cross-section vaned members between which the gas entering the outlet tube must pass in flowing to the outlet end of the outlet tube. A portion of the sidewall of the outlet tube of the cyclone-type particulate collector is provided with a gate to act as a particulate skimmer which opens into the gas inlet volute for recirculation of the skimmed particles.

Abstract: A cyclone vortex type air cleaner and particulate concentrator is provided having greatly improved air cleaning efficiency as the dirty gas stream is subjected to two distinct skimming operations; one between the gas inlet scroll and the outlet tube and the other at the exit from the gas discharge scroll. The invention may further include means for increasing agglomeration of the particulate by increasing centrifugal separation in an inlet scroll, an outlet scroll and in the outlet tube from the shell or body of the cyclone.