METHOD OF AND APPARATUS FOR CONTROLLING THE RATE OF FEEDING MATERIAL TO METERING DISTRIBUTORS,IN PARTICULAR SEEDERS

摘要

Method and apparatus are disclosed herein in which particulate material, e.g., seeds, is transferred from a main hopper to an auxiliary storage bin (which may be combined with a dispensing unit) through a hermetic conduit having a rising portion. An air stream produced by a source of compressed air entrains the particulate materiel. A partial vacuum is created in the conduit and dissipates as the auxiliary storage bin fills, reaching or surpassing zero when the auxiliary storage bin is full. The particulate material is introduced into the conduit at the same location as the partial vacuum therein. In a preferred embodiment the particulate material may be drawn out of the main hopper through an outlet chute connected proximate to the construction of a venturi which is connected between the source of compressed air and the conduit. Alternatively two venturis may be provided, one for drawing off particulate material from the main hopper and the other for conveying the entrained particulate material to the auxiliary storage bin. The two venturis may be disposed side by side and connected through a single passage to a source of compressd air at one of their ends and opening into the top side of the rising portion at their other ends.