GB1090578A - Wind sifter - Google Patents

Abstract

1,090,578. Pneumatic separators. RHEINISCHE KALKSTEINWERKE G.m.b.H. Sept. 20, 1965 [Sept. 18, 1964], No. 39934/65. Heading B2H. A pneumatic classifier for separating particulate material into different size fractions comprises a housing 1 enclosing a number of coaxially arranged cone-shaped members 4, 4', 4". The material to be classified is fed via a pipe 5 on to a non-rotating distributor plate 6 which is vibrated by drive means 7. The plate 6 contains passages 8 through which an air stream induced by a fan 2 passes as indicated by the arrows. The size of the holes is such that none of the particulate material can pass through them. One or more mechanically or electrostatically acting filters 11 are connected below the plate 6 to the vibrator drive means 7. In operation, the fine and medium particles are carried from the plate 6 by means of the upward current of air and enter the annular space between the housing 1 and the cone member 4. The medium particles drop down and leave through an outlet 9. The fine particles are entrained by the current of air between guide plates 13, Fig. 2, and through helical passages 10 into the interior of the cone member 4" where they collect on to the filter 11 and the plate 6 until they are displaced therefrom by the vibration as agglomerates which fall down and pass through the passages 10 into the space between the members 4 and 4' and are discharged through an outlet 9'. The coarse particles, which are not carried by the upward air current, are conveyed by the vibrating movement of the plate 6 to helically arranged conduits 12 between the members 4' and 4" and are discharged through an outlet 9".