Abstract: Pressure control apparatus for a cyclone separator includes a variable air flow control valve in at least one line exiting from the separator. The air flow through that valve is adjusted in response to pressure changes in the separator. A flow control valve with adjustable bladders is preferred.

Abstract: A cyclone separator for segregating a mixture of light and heavy particles from a gas stream carrying such particles includes a separating chamber connected at its upper end to a gas discharge chamber and connected at its lower end to a particle discharge chamber. A feed tube spirally wraps at least partially around the upper gas discharge chamber and communicates with the separating chamber to direct a stream containing the gas and particles into the separating chamber in a downward, radial direction. Some of the entering gas and some minute dust particles from the separating chamber exit through the gas discharge chamber and the balance of particles exit through the lower particle discharge chamber into a particle collector or bin. The separating chamber includes a section containing porous material through which a large percentage of entering gas can exit, thereby reducing the volume and velocity of gas exiting through the upper and lower discharge chambers.

Abstract: An impeller for a materials handling fan can be made in several different diameters utilizing a single central hub of fixed diameter. The single central hub is designed to withstand the varying stresses imposed by different impeller diameters. A circular backplate or shroudplate is welded to the hub to extend the effective diameter of the hub.