Abstract:
Existing seed treatment applicators distribute seed into an uneven annular veil and results in wasted seed treatment fluid and unnecessarily long mixing/drying times. We developed a seed distribution apparatus comprising a partially porous, frustoconical restricting assembly that is mounted above and partially receives a conical distributing assembly. The orientation of the distributor and restricting assemblies provides three different seed flow paths to provide a substantially even annular veil of seed to the seed treatment housing.

Description:
CROSS-REFERENCES 
     Not Applicable. 
     GOVERNMENT RIGHTS 
     Not Applicable. 
     REFERENCE TO CDS 
     Not Applicable. 
     FIELD OF THE INVENTION 
     The present invention is in the technical field of regulating the flow rate and dispersion pattern of a particulate matter, such as seed flow within a seed treatment applicator. 
     BACKGROUND 
     Seeds planted for agricultural and other purposes are often treated with an agrichemical such as insecticides, inoculants, micronutrients or other beneficial compositions prior to planting. Treatment may accomplish various purposes including inhibiting the growth of insects, bacteria, molds, fungus, and parasites that are destructive to the seed and plant growth. Seed treatments are commonly applied by spraying a liquid composition to the surface of seed as the seed falls through a seed treatment applicator. Direct application of the seed treatment fluid to the seed before planting requires a smaller quantity of seed treatment composition than the traditional field application of treatment fluids. 
     SUMMARY 
     Direct application of the seed treatment fluid to the seed before planting requires a smaller quantity of seed treatment composition than the traditional field application of treatment fluids. An ideal treatment applicator system applies treatment fluid uniformly across the surface of the seed thereby minimizing the time the treated seed needs to be mixed in a mixing/drying drum to ensure complete and even coverage of the treatment fluid. 
     Seed flows into the applicator under the force of gravity. A metered quantity of seed flows into the applicator, first into a distribution housing and then into a treatment housing. In the treatment housing, airborne droplets of treatment fluid are applied to the seed surface using an atomizer. 
     Upon entering the applicator, the seed flow is directed into an annular veil in the distribution housing by means of a conical distributing assembly. The atomizer—positioned below the distributing assembly—sprays droplets of treatment fluid from the center of the treatment housing outwardly. These airborne droplets make contact the interior perimeter of the annular veil of seed. 
     However, in existing treatment applicators the seed often flows unevenly over the conical housing. This results in uneven annular veil of seed and an uneven application of the seed treatment fluid. Treatment systems commonly rely on a rotating mixing drum to compensate for uneven application of the seed treatment to the seed flow. This results in longer seed drying/mixing times and can result in wasted seed treatment fluid. 
     We solved this problem by incorporating a restricting assembly within the seed distribution housing of the applicator. The restricting assembly retains at least a portion of the seed that flows into the seed distribution housing. The distributing assembly is partially disposed within the restricting assembly. The restricting assembly has a downwardly converging frustoconical surface comprising a lower retaining portion, a porous portion, and an upper retaining portion. A first seed flow path is defined by the lower retaining portion of the restricting assembly and the downwardly diverging conical surface of the distributing assembly. The first seed flow path provides a substantially even annular veil of seed. At low seed flow rates, up to approximately 700 to 1,000 pounds per minute, the seed flows through the seed distribution housing primarily through the first seed flow path. 
     The restricting assembly redirects seed flow, limiting lateral motion of the incoming seed flow and directing the seed flow to fall substantially vertically over the distributing assembly and through the distribution housing and the treatment housing. However, it is important that seed flow rate is not vertically restricted for extended periods of time, especially at higher seed flow rates. This is important because the atomizer applies the treatment fluid in response to the measured flow rate of seed entering the seed distribution housing. 
     In order to minimize the retention of seed in the distribution housing, we added a porous portion to the restricting assembly. The porous portion can comprise a plurality of seed outlet openings. Collectively, the seed outlet openings define a second seed flow path. The size, shape, and placement of these seed outlet openings, in combination with the first seed flow path, allow seed to flow through the distributor at a medium seed flow rate. The medium seed flow rate can range from at least 700 to 1,000 pounds per minute up to approximately 1,800 pounds per minute. 
     Under high seed flow rates—rates in excess of 1,800 pounds per minute—the seed will flow through the first seed flow path, through the second seed flow path, and begin to flow over the top retaining portion of the restricting assembly. A third seed flow path is defined by the radial space between the upper inlet end of the restricting assembly and the interior surface of the distribution housing. 
     The seed flow rate through the first seed flow path can be adjusted by adjusting the position of the restricting assembly relative to the distributing assembly. At least one of the restricting assembly and the distributing assembly can be adjustably mounted within the seed distribution housing. The restricting assembly can be adjustably mounted at a predetermined height above the distributing assembly, such that the lower retaining portion of the restricting assembly partially receives a portion of the distributing assembly. As described above, the first seed flow path is defined by the annular space between the lower retaining portion of the restricting assembly and the downwardly diverging conical surface of the distributing assembly. The lower retaining portion is oriented to at least partially restrict seed flow through the first seed flow path such that the restricted seed accumulates within the restricting assembly and flows through the at least one of the seed outlet openings. Adjustments to the position of either the restricting assembly or the distributing assembly affect the flow rate of seed through the first seed flow path. 
     The width of the first seed passage can be adjusted based on the seed type, seed size, or to achieve a targeted seed flow rate through the first seed flow path. In one embodiment, the width of the first seed passage can range from 0.25 inches to 1.0 inch. In a preferred embodiment, the width of the first seed flow passage is between 0.625 inches to 0.75 inches. In another embodiment, the width of the first seed flow passage is determined based on flow rate of the seed, for example the width of the first seed flow passage permits seed flow up to 700 pounds per minute. 
     The seed flow rate through the second seed flow path can be adjusted by altering the configuration of the porous portion of the restricting assembly. The size, number, and shape of the seed outlet openings in the restricting assembly can be configured such that the discharge rate of seed flow through the first seed flow passage and through the perforations is sufficient to achieve a medium seed flow rate. In a preferred embodiment, at least one-half of the surface area of the frustoconical surface of the restricting assembly comprises seed outlet openings. The pitch of the downwardly converging frustoconical surface may also be altered to present a more vertical or a more horizontal seed outlet opening. In a preferred embodiment, the angle of the downwardly converging frustoconical surface is approximately 30° from vertical. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Aspects are illustrated by way of example, and not by way of limitation, in the accompanying drawings, wherein: 
         FIG. 1  is a side perspective view of the seed treatment applicator; 
         FIG. 2  is an elevated side perspective cutaway of the distribution housing and the treatment housing; 
         FIG. 3  is a side perspective cutaway of the distribution housing and the treatment housing; 
         FIG. 4  is an elevated side perspective of the restricting assembly and the distributing assembly. 
     
    
    
     DETAILED DESCRIPTION 
     The seed treatment applicator  100  is shown in  FIG. 1 . A regulated flow of seed enters into the applicator  100  from above. The seed flows into a seed distribution housing  108  through a seed inlet  109 . The seed inlet path is shown in cutaway in  FIG. 2 . 
     The seed flow is shaped within the distribution housing  108 —which is shown in cutaway in  FIGS. 2 and 3 . First, the seed encounters a distributing assembly  300 . The distributing assembly  300 , as shown in  FIGS. 2-4 , has a downwardly diverging conical surface  306 , a narrow upper portion  302  and a wide lower portion  304 . 
     After the seed flow is shaped into an annular veil, the seed flows into a seed treatment housing  102 . An atomizer  402  applies fluid seed treatment to the annular veil of seed within the seed treatment housing  402 . The treated seed then flows through a transition housing  406  and into a mixing/drying drum  404 . Treatment fluid is then applied to the annular veil of seed in the seed treatment housing  102 . 
     In existing applicators, the seed is allowed to fall disproportionately over one side of the distributing assembly  300 . This creates an uneven annular veil of seed flow, which results in an uneven application of seed treatment fluid, wastes valuable seed treatment fluid, and requires longer mixing time in the mixing/drying drum  404 . 
     As illustrated in  FIGS. 2-4 , the present disclosure provides the seed treatment applicator with a substantial even annular veil of seed by directing the seed flow through multiple seed flow paths through the use of a restricting assembly  200 . As shown in  FIGS. 2-4 , the restricting assembly  200  has a downwardly converging frustoconical surface  202 . The downwardly converging frustoconical surface  202  has an upper retaining portion  206 , a lower retaining portion  208 , and a porous portion  210 . The restricting assembly  200  also has an upper opening  212  for receiving a flow of seed and a lower opening  214 . 
     The restricting assembly  200  is positioned within the distributing housing  108  such that at least a portion of the distributing assembly  300  is partially inserted within the lower opening  214  of the restricting assembly  200 . As shown in  FIGS. 2-4 , the upper narrow portion  302  of the distributing assembly  300  is disposed within the restricting assembly  200  and a wide lower portion  304  of the distributing assembly  300  is not disposed within the restricting assembly  200 . In a preferred embodiment, the wide lower portion  304  of the distributing assembly  300  radially extends beyond the lower retaining portion  208  of the restricting assembly  200 . 
     A first seed flow path through the distribution housing  108  is defined by the annular opening between the lower retaining portion  208  of the restricting assembly and the downwardly diverging conical surface  306  of the distributing assembly  300 . At low seed flow rates the seed flow travels primarily through this first seed flow path. 
     As the seed flow enters the distribution housing, the seed flow is received through the seed inlet  109 . The seed flow then enters the interior of the restricting assembly  200 . The lower retaining portion  208  is oriented to at least partially restrict seed flow through the lower opening  214  such that the restricted seed accumulates within the restricting assembly  200 . The lower retaining portion  208  also restricts lateral movement of the seed flow. At low seed flow rates—in one embodiment up to approximately 700 to 1,000 pounds per minute—the entire seed flow is capable of flowing through this first seed flow path. The width of the first seed flow path can be adjusted, as discussed below. 
     The restricting assembly  200  temporarily restricts the seed flow, in order to direct the seed flow through the first seed flow path. The restricting assembly  200  adequately restricts lateral motion of the seed flow and directs the seed flow vertically over the distributing assembly  300 . However, it is important that seed flow rate is not vertically restricted for extended periods of time, especially at higher seed flow rates. This is important because a controller (not shown) regulates the fluid treatment flow rate to the atomizer  402  in response to the measured flow rate of seed entering the applicator  100 . 
     A second seed flow path minimizes the retention of seed within the restricting assembly  200  at higher seed flow rates. The second seed flow path is defined by a plurality of seed outlet openings  204  through the porous portion  210  of the restricting assembly  200 . The even distribution of the seed outlet openings  204  about the downwardly converging frustoconical surface  202  maintains the even annular veil of the seed flow. At medium seed flow rates, seed flows through the first seed flow path and the second seed flow path. In one embodiment, the medium seed flow rate is between 700 pounds per minute and 3,000 pounds per minute. In a preferred embodiment, at least one-half of the surface area of the frustoconical surface  202  of the restricting assembly  200  comprises seed outlet openings  204 . 
     As seed flows into the restricting assembly  200  at medium seed flow rates, the seed flow is restricted such that the seed accumulates over the top of the lower retaining portion  208 . Seed then begins to flow through the at least one of the seed outlet openings  204 . As shown in  FIGS. 2-4 , the seed outlet openings are defined by the upper retaining portion  206 , the lower retaining portion  208 , and a plurality of ribs  216 . The ribs  216  continue to partially restricts the seed flow through the distribution housing  108 , thereby restricting lateral motion of the seed flow and facilitating seed flow through the evenly spaced seed outlet openings  204 . 
     A third seed flow path allows seed to flow through the distribution housing  108  under high seed flow rates—in one embodiment, high seed flow is a rate in excess of 3,000 pounds per minute. The third seed flow path is defined by the radial space between the upper retaining portion  206  of the restricting assembly  200  and an interior surface  114  of the seed distribution housing  108 . At high seed flow rates the seed flows through the first seed flow path, the second seed flow path, and the third seed flow path to produce the annular veil of seed flow to the atomizer. 
     As shown in  FIGS. 2-4 , at least certain portions of the distributing assembly  300  are received within lower opening  214  of the restricting assembly  200 . When partially received, the narrow upper portion  302  is received within the restricting assembly  200  and the wide lower portion  304  is not received within the restricting assembly  200 . In one embodiment, the wide lower portion  304  of the distributing assembly  300  radially extends beyond the lower retaining portion  208  of the restricting assembly  200 . In another embodiment, the wide lower portion  304  of the distributing assembly  300  radially extends beyond the upper retaining portion  208  of the restricting assembly  200 . 
     In the illustrated embodiment, the distributing assembly  300  is mounted to the treatment housing  102  with a plurality of brackets  308 . The restricting assembly is similarly mounted to the seed distribution housing  108  with a plurality of brackets  218 . These brackets  308 ,  218  are depicted as welded metal plates that mount the respective assembly to the respective housing. It should be apparent to one skilled in the art that these mounts  210  may be a variety of mechanisms, such as welded rods or fasteners such as bolts or screws. As illustrated, the distribution housing  108  is mounted to the applicator structure  400  with a fastener that passes through an flange  109  and is received by the applicator frame  106 . The structure  400  is illustrated as supporting the seed distribution housing above the seed treating portion of the seed treater 
     The seed flow rate through the first seed flow path can be adjusted by changing the orientation of the restricting assembly  200  relative to the distributing assembly  300 . At least one of the restricting assembly and the distributing assembly can be mounted on a vertically adjustable mount upon the structure  400  such that the orientation between the restricting assembly  200  and the distributing assembly  300  is adjustable. For example, seed flow rate can be adjusted by raising or lowering the restricting assembly  200 . As shown in  FIGS. 2-3 , the restricting assembly  200  is mounted to the seed distribution housing  108  with a plurality of mounting brackets  218 . The seed distribution housing  108  is mounted upon the structure  400  with a flange  112  and a fastener (not shown) that passes through the flange  112  and is received by the structure  400 . One or more washers (not shown) can be inserted between the upper housing  109  and the applicator frame  106  to raise or lower the distribution housing  108 . It should be apparent to one skilled in the art that these height adjustment mechanism may be a variety of mechanisms, such as hydraulic cylinders, fasteners such as bolts or screws, inclined planes, or levers. As the distribution housing  108  is raised or lowered, the restricting assembly  200  is raised or lowered. Raising or lowering the restricting assembly  200  relative to the distributing assembly  300  changes the width of the first seed flow passage due to the downwardly diverging conical surface  306  of the distributing assembly  300 . The width of the first seed flow passage can range from 0.25 inches to 1.0 inch. In a preferred embodiment, the width of the first seed passage is between 0.625 inches to 0.75 inches and permits seed flow up to 700 pounds per minute. The minimum width of the first seed flow path prevents seed buildup and allows a sufficient seed flow into the seed treatment housing  102 . 
     The width of the first seed flow passage can be adjusted based on the seed type or seed size, to achieve the targeted low seed flow rate. For example, the size of wheat seed is much smaller than bean or corn seed. For another example, the size of a certain variety of seed can vary between batches. In order to accommodate different seed varieties or seed sizes and maintain the flow rate, the restricting assembly  200  can be adjustably mounted relative to the distributing assembly  300 . 
     In another embodiment, the restricting assembly  200  can be mounted upon a graduated ramp that allows the restricting assembly  200  or the distribution housing  108  to be rotated to modify the height of the restricting assembly  200  relative to the distributing assembly  300 . The graduated ramp can have alternating inclined ramp portions and level portions. The graduated ramp allows the restricting assembly  200  to be adjustable—by rotation—to discrete predetermined heights—or steps—relative to the distributing assembly  300 , and thereby adjusting the maximum seed flow rate through the first seed flow path. 
     In another embodiment, the distance between the restricting assembly  200  and the distributing assembly  300  can be adjusted with an actuator, such as a hydraulic, pneumatic, or mechanical actuator. The actuator adjusts the height of the restricting assembly  200  relative to the distributing assembly  300 , and thereby controls the maximum seed flow rate through the first seed flow passage  220 . 
     The size of the seed outlet openings  204  in the restricting assembly  200  is configured such that the sum discharge rate of seed flow through the first seed flow passage and through the perforations is sufficient to achieve a medium seed flow rate. In one embodiment, the surface area of the perforations in the sidewall corresponds to approximately one-half of the surface area of the sidewalls and permits seed flow up to approximately 3,000 pounds per minute. The pitch of the downwardly converging frustoconical surface can also be altered to present a more vertical or a more horizontal seed outlet opening. In a preferred embodiment, the angle of the downwardly converging frustoconical surface is approximately 30° from vertical. 
     The restricting assembly  200  is preferably made of a rigid material, such as steel, aluminum, or plastic. The distributing assembly  300  is also made of a rigid material—in a preferred embodiment the distributing assembly  300  is made of a plastic. The plastic decreases seed damage, less impact as seed falls. The distributing assembly  300  is mounted over the motor  400 . The angle of the downwardly diverging conical surface  306  of the distributing assembly  300  is such that prevents seed buildup and directs the seed flow into an annular veil. 
     In another embodiment, the restricting assembly  200  is mounted to a bearing (not shown) that allows the restricting assembly  200  to rotate within distribution housing  108 . The restricting assembly  200  rotates continuously under seed flow. An angled flute (not shown) can be mounted to each of the perforations  204  in the restricting assembly  200  and rotate with the restricting assembly  200 . The rotating angled flutes would provide even flow rate of seed about the central vertical axis under medium seed flow rates. 
     The tip of the seed distribution housing is described as conical. As used in this document, conical can refer to a shape where the narrow end is rounded, flattened, or pointed. As used in this document, frustoconical means having the shape of a cone with a portion of the narrow end—or tip—removed. 
     In the Summary above, the Detailed Description, and in the accompanying drawings, reference is made to particular features of the invention. The reader should understand that the disclosure of the invention in this specification includes all possible combinations of such particular features. For example, where a particular feature is disclosed in the context of a particular aspect or embodiment of the invention, or a particular claim, that feature can also be used, to the extent possible, in combination with and/or in the context of other particular aspects and embodiments of the invention, and in the invention generally. 
     The term “comprises” and its grammatical equivalents are used in this document to mean that other components, steps, etc. are optionally present. For example, an article “comprising” or “which comprises” components A, B, and C can consist of components A, B, and C, or can contain not only components A, B, and C but also one or more other components.