s of the motion-generator shaft. Rotation of the top weight creates vibration in th horizontal plane, which causes material to move across the screen cloth to the periphery. The lower acts to tilt the machine, causing vibration in the vertical and tangential planes. Speed and spiral pattern of matrial travel over the screen cloth can be set by the operator for maximum throughout and screening efficiency of any screenable product. wetordry. heavyorligh. coarse ofr fin hotorcold.