Venturi system for agricultural spreaders of solid particles

In combination with a pressurized pneumatic system for substantially uniform distribution of particulate solids upon the soil from a system mounted upon a self-propelled vehicle and including a reservoir with a source of supply of particulate solids to be distributed, a distribution head means for metering and apportioning particulate solids from said source into a plurality of generally aliquot portions, a plurality of elongated hollow delivery booms of predetermined and differing lengths extending laterally outwardly of said vehicle from a proximal end to a distal discharge end, a source of compressed air for creating a flow of pressurized air through said hollow elongated booms, a plurality of tubular feed members, each extending between said distribution head and a selected one of said delivery booms, for delivery of each of said aliquot portions from the proximal end to the distal discharge end of a boom, and a juncture point adjacent the proximal end of each of said hollow elongated booms for introducing one aliquot portion of particulate solids from each of said tubular feed members to the flow of pressurized air moving through each of said delivery booms;

• the improvement comprising:
• (a) Venturi means mounted within each of said hollow delivery booms between said juncture point and said proximal end immediately upstream from said juncture point, said Venturi means comprising a flow wedge defining a radially inwardly converging inlet ramp portion, a radially outwardly diverging outlet ramp portion and a throat portion a linear apex along the intersection intermediate said inlet and outlet ramp portions, with said throat portion defining the linear apex which extends generally along a substantially horizontally disposed linear chordal line across the entire width of said hollow delivery boom;
• (b) said Venture means further comprising generally planar blade means cooperating with said flow wedge and being mounted along each of said hollow delivery boom in generally opposed relationship to the apex forming the throat portion of said Venturi means, said blade means being spaced from said tubular feed member and disposed immediately upstream therefrom and generally adjacent to and along the same side of the axis of the hollow delivery boom as the adjacent tubular feed member, said blade means further having a linear inner tip terminating at an edge which extends generally along a chordal line across said hollow delivery boom and extends radially inwardly of said hollow boom at an angle which converges toward the distal end of said boom, and wherein the inner edge of said blade means is arranged in generally parallelly disposed relationship with the apex forming said Venturi throat portion, and with the inner edge of said blade means intersecting at least a portion of a projected extension of the tubular feed member from its point of intersection with said hollow delivery boom, the arrangement being such that said Venturi means creates a partial vacuum within said hollow delivery boom adjacent and along the juncture point with said tubular feed member;
• and
• (c) said hollow delivery boom being substantially free of obstructions between said Venturi means and said distal discharge end.