Abstract: A centrifuge for sifting granular material, ranging in particle size from a few microns to several hundred microns, for example, comprises an upwardly concave frustoconical disk rotatable about a horizontal axis and provided with a similarly shaped cover defining therewith a narrow annular gap of outwardly converging radial cross-section. Air, or some other gaseous or liquid fluid, is axially introduced from above into that gap together with the granular material to be centrifuged, the fluid stream imparting to the smaller particles an added acceleration making the velocities of all particles substantially equal at the disk periphery.

Abstract: This invention relates to a separator with a vertical axis, with a fan for producing the separating air stream coaxially disposed on a hollow shaft in the separator housing, a scatter plate rotating in the separator chamber, a counter-impeller system also rotating in the separator chamber, together with a drive mechanism mounted on the separator housing cover and comprising a drive motor, first gearing coupled with the hollow fan-shaft, and second adjustable gearing which drives the scatter plate and the counter-impeller system through a core shaft coaxially disposed in the hollow fan-shaft.

Abstract: Method and apparatus for classifying articles of varying size from a stream of particulate material in which the stream is subjected to centrifugal forces to provide an annular dispersion, and a stream of air is directed substantially perpendicular through the dispersion to aid in separating the fines from the coarser particles.

Abstract: In classifying apparatus of the type wherein upward whirling flow of fluid is used to separate coarse and fine particles of the particulate material, rotary vanes are mounted on the upper portion of a housing for separating and discharging fine particles, and a rotary disc carrying a plurality of nozzles is provided for projecting jet streams of the fluid against the inner wall of the housing. Vertical and inclined guide plates are provided near the inlet port of the fluid for smoothly guiding coarse particles falling down along the inner side of the housing without being disturbed by the whirling flow of the fluid admitted through the inlet port.

Abstract: Rotary distributor plate for distributing particles of solid or liquid material in a centrifugal-type classifier includes a plate-like member having an upper surface, and means carried by the surface for uniformly throwing off from the plate-like member particles of material fed thereto.

Abstract: A centrifugal separator is provided with a rotary distributor provided with a plurality of vertically spaced coaxial rotating disks, in which the upper rotating disk is of smaller diameter than the lower rotating disk. The distance between the disks may be adjustable. The lower disk baffles an updraft separating air current whereby powdered material is separated from the coarser material as centrifuged from the upper disk, and any material escaping the upper disk without being thrown thereby into the air stream drops down on the larger lower disk and is thrown into the air stream by the lower disk. Either or both of the disks may be provided with agitator vanes.