Patent ID: 6818033
Filing Date: 2004-11-16
Classification: A47L,B01D,B04C,Y02A,Y10S

Abstract:
Apparatus for separating particulate material from an airstream established by suction, comprising:(1) a primary separation chamber in which particles are separated from the airstream therein by centrifugal force; (2) a main particle collecting region into which the particles separated by the primary separation can fall under gravity; (3) a secondary separation chamber downstream of the primary chamber, to which air and particles not separated in the first chamber, pass; (4) an air outlet in the secondary chamber through which air substantially free of particles can exit; (5) an intermediate particle collecting region associated with the secondary chamber, in which particles collect after separation by centrifugal force from the air flowing through the secondary chamber; (6) a valve between the intermediate particle collecting region and a second particle collecting region, having a valve closure member which closes the valve while air flows through the apparatus but which opens the valve when airflow ceases, to allow particles in the intermediate region to pass into the second region; characterised in that the valve closure member presents a conical or frusto-conical surface to an annular seating which includes an O-ring against which the said surface engages when the valve is closed.