a cyclonic separating apparatus for separating particles from a dirt - laden airflow includes a cyclone for separating and collecting dirt and dust from the dirt - laden airflow . the cyclone has an air inlet , an air outlet , a longitudinal axis and a wall . the wall includes a first portion and a second portion spaced farther from the longitudinal axis than the first portion , the first and second portions being spaced along the longitudinal axis . the cyclone also includes at least one lip extending from the first portion of the wall into a portion of the cyclone surrounded by the second portion of the wall . by providing a cyclone with a wall having two portions of different sizes and a lip extending from the portion with the smaller size into the portion with the larger size , the risk of blockages due to re - entrainment and movement of dirt and dust within the cyclonic separating apparatus is reduced .