(under subclass 146) Methods and means wherein material carries by hollow rotating cylinders or drums is agitated (usually by lifting and dropping) by the drum or a cooperating element thereof and subjected to a flow of gas which assorts the same.
(1) Note. The distinction between this subclass and subclass 473 is that in this subclass all the material is definitely and repeatedly dropped into the gaseous current, while in the latter subclass the heavier components remain on the bottom of the cylinder or drum and are retained as a body or stratum or are conveyed along the bottom as a stratum. The relations of the subclasses are otherwise very close, and search in one should always by extended into the other.
SEE OR SEARCH THIS CLASS, SUBCLASS:
233+, appropriate subclasses for drum sifters.
473, (see (1) Note)
SEE OR SEARCH CLASS
241, Solid Material Comminution or Disintegration, 45, and 54 for comminutors or grinders of the horizontal drum type employing a gaseous current passing through the grinding zones.
