Grain silo for storage and mixing of layers of different grain kinds

In a grain silo of the type including a central bottom outlet opening and conveyor means connected thereto, and wherein the silo is loaded with two layers of different grain kinds, in a predetermined ratio one above the other, and of which the upper layer is taken off centrally by trickling off downwardly through the central bottom outlet opening, the improvement which comprises the central bottom outlet opening of the silo being in the shape of a conical deflector having a truncated conical surface with the point thereof upwardly facing, and an outer peripheral edge disposed at a predetermined distance from the bottom of the silo, the silo being provided at the bottom end thereof with an annular zone defined outwardly by the silo wall and inwardly by said outer peripheral edge of said conical deflector and having a diameter at least equal to half the diameter of the silo, and a rotatable blade mounted in the bottom of the silo beneath said conical deflector for rotation around the central axis of the silo, for conveying grain toward the center of the silo and said conveyor means, said annular zone being partly covered by said blade at said outer peripheral edge of said conical deflector, the free end of said blade engaging a grain slope forming in said annular zone under said outer peripheral edge to convey grain to said conveyor means where such grain is mixed with grain of a different kind taken off the upper layer, so that a desired mixture relation of different grain kinds can be obtained from two unmixed layers of different grain kinds.