A vacuum cleaner cyclone separator having a cyclone chamber with an air inlet and an air outlet. The cyclone chamber directs an airflow into a cyclonic pattern to remove a first amount of debris from the airflow. A filter shroud is located within the cyclone chamber and separates the air inlet from the air outlet. The filter shroud includes an air-pervious filter surface adapted to allow the airflow to pass from the air inlet to the air outlet and remove a second amount of debris from the airflow. One or more protrusions are associated with the filter surface, and configured and dimensioned to direct at least a portion of the airflow passing generally parallel to the filter surface away from the filter surface before passing through the filter surface. A dirt collection assembly having a cyclone separator and a method for using a cyclone separator are also disclosed.
