Seed singulator

Abstract

A seed singulator for use with a vacuum disk having a seed face and a shoulder. The seed singulator has a first member and a second member supported by biasing members. The first member has upper lobes disposed at a radius of curvature slightly less than the outside radius of a row of apertures on a seed plane of the vacuum disk. The seed member has lower lobes disposed at a radius of curvature slightly greater than the inside radius than the row of apradius. The biasing members permit the lobes to move with the seed plane and the shoulder as the vacuum disk rotates thereby maintaining their position with respect to the apertures.

The invention claimed is: 
     
       1. In combination, a seed singulator and a vacuum disk, the vacuum disk having a seed plane and a row of apertures at a radius R 1  from the center of the disk, a radius R 2  to the outside of the apertures, a radius R 3  to the inside of the apertures, and a radius R 4  to an annular shoulder of the vacuum disk, said singulator comprising:
 a first member having upper lobes disposed at a radius of curvature slightly less than the radius R 2 , said first member further having a surface biased radially toward the annular shoulder of the vacuum disk; 
 a second member having lower lobes disposed at a radius of curvature slightly greater than the radius R 3 ; 
 said upper and lower lobes having substantially co-planar is surfaces biased axially against the seed plane of the vacuum disk. 
 
     
     
       2. The combination of  claim 1  wherein said singulator includes three upper lobes and two lower lobes. 
     
     
       3. The combination of  claim 1  wherein said surface of said first member of said singulator has a radius of curvature substantially the same as the radius R 4 . 
     
     
       4. The combination of  claim 3  wherein said first member and said second member of said singulator comprise a single unitary element. 
     
     
       5. The combination of  claim 4  wherein said singulator further includes an axial spring and a radial spring whereby said axial spring biases said single unitary element in a axial direction and said radial spring biases said single unitary element in a radial direction. 
     
     
       6. The combination of  claim 4  wherein said upper lobes and said lower lobes move with the seed plane and with the shoulder while maintaining the position of the upper lobes with the radius R 2  and the lower lobes with the radius R 3 . 
     
     
       7. The combination of  claim 1  wherein said upper lobes and said lower lobes move with the seed plane and at least said upper lobes move with the shoulder while maintaining the position of the upper lobes with the radius R 2 . 
     
     
       8. A seed meter, comprising:
 a seed disc having a plurality of seed apertures, said seed disc disposed to entrain seeds from a seed pool onto said seed apertures by vacuum; and   a singulator disposed to remove excess seeds from said seed apertures, said singulator disposed to resiliently slidingly contact said seed disc as said seed disc moves relative to said singulator, wherein said singulator is biased toward an axial center of said seed disc.   
     
     
       9. The seed meter of claim 8, wherein an arcuate singulator surface of said singulator is biased against and slidingly contacts an arcuate seed disc surface of said seed disc, wherein said arcuate singulator surface faces toward said axial center of said seed disc. 
     
     
       10. The seed meter of claim 8, further comprising: a seed side housing enclosing said seed pool; and a radial spring fixed to said singulator, wherein said singulator is biased toward said axial center of said seed disc by a force transmitted to said seed side housing. 
     
     
       11. The seed meter of claim 8, wherein said radial spring comprises a metal wire. 
     
     
       12. A seed meter, comprising:
 a seed disc having a plurality of seed apertures, said seed disc disposed to entrain seeds from a seed pool onto said seed apertures by vacuum; and   a singulator disposed to remove excess seeds from said seed apertures, said singulator disposed to resiliently slidingly contact said seed disc as said seed disc moves relative to said singulator, wherein said singulator is biased toward said seed disc along a direction parallel to a rotational axis of said seed disc.   
     
     
       13. The seed meter of claim 12, further comprising: a seed side housing enclosing said seed pool; and an axial spring fixed to said singulator, wherein said singulator is biased toward said axial center of said seed disc by a force transmitted to said seed side housing. 
     
     
       14. The seed meter of claim 13, wherein said singulator is fixed to said axial spring, and wherein said axial spring supports a weight of said singulator when said seed disc is removed from the seed meter. 
     
     
       15. A seed meter, comprising:
 a seed disc having a plurality of seed apertures, said seed disc disposed to entrain seeds from a seed pool onto said seed apertures by vacuum; and   a singulator disposed to remove excess seeds from said seed apertures, said singulator disposed to resiliently slidingly contact said seed disc as said seed disc moves relative to said singulator, wherein a center of each said seed aperture is disposed at an aperture radius from a rotational axis of said seed disc, wherein said singulator comprises a first upper lobe disposed at an upper lobe radius from said rotational axis of said seed disc, said upper lobe radius being greater than said aperture radius, wherein said first upper lobe contacts seeds on said seed apertures, and wherein said singulator comprises a first lower lobe disposed at a lower lobe radius from said rotational axis of said seed disc, said lower lobe radius being less than said aperture radius, wherein said first lower lobe contacts seeds on said seed apertures.   
     
     
       16. The seed meter of claim 15, wherein said singulator comprises a second lower lobe disposed at said lower lobe radius, wherein said second lower lobe contacts seeds on said seed apertures. 
     
     
       17. The seed meter of claim 16, wherein said first upper lobe contacts seeds on said seed apertures before said first lower lobe contacts seeds on said seed apertures. 
     
     
       18. The seed meter of claim 16, wherein said singulator comprises a second upper lobe disposed at said upper lobe radius, wherein said second upper lobe contacts seeds on said seed apertures. 
     
     
       19. A seed meter, comprising:
 a seed disc having a plurality of seed apertures, said seed disc disposed to entrain seeds from a seed pool onto said seed apertures by vacuum; and   a singulator disposed to remove excess seeds from said seed apertures, said singulator disposed to resiliently slidingly contact said seed disc as said seed disc moves relative to said singulator, wherein a center of each said seed aperture is disposed at an aperture radius from a rotational axis of said seed disc, wherein said singulator comprises a first upper lobe disposed at an upper lobe radius from said rotational axis of said seed disc, said upper lobe radius being greater than said aperture radius, wherein said first upper lobe contacts seeds on said seed apertures, and wherein said first upper lobe comprises a lower lobe arcuate edge, said lower lobe arcuate edge curved away from approaching seeds on said seed apertures.   
     
     
       20. The seed meter of claim 15, wherein said first lower lobe comprises an upper lobe arcuate edge, said upper lobe arcuate edge curved away from approaching seeds on said seed apertures. 
     
     
       21. The seed meter of claim 16, wherein said first upper lobe and said first lower lobe each comprise a leading edge, said leading edge being in a swept-back orientation relative to the rotational direction of said seeds. 
     
     
       22. The seed meter of claim 16, wherein said first upper lobe and said first lower lobe each comprise a leading edge, said leading edge retreating along the direction of seed rotation as said leading edge extends toward the seed aperture radius. 
     
     
       23. The seed meter of claim 8, further including a plurality of cavities formed in said seed disc, said cavities extending radially inward of said seed apertures. 
     
     
       24. The seed meter of claim 15, further including a plurality of cavities formed in said seed disc, said cavities extending radially inward of said seed apertures. 
     
     
       25. The seed meter of claim 8, further including a plurality of fins formed in said seed disc, said fins extending radially inward of said seed apertures. 
     
     
       26. The seed meter of claim 15, further including a plurality of fins formed in said seed disc, said fins extending radially inward of said seed apertures. 
     
     
       27. A seed meter, comprising:
 a seed disc having a plurality of seed apertures, said seed disc disposed to entrain seeds from a seed pool onto said seed apertures by vacuum; and   a singulator disposed to remove excess seeds from said seed apertures, said singulator disposed to resiliently slidingly contact said seed disc as said seed disc moves relative to said singulator, wherein said seed disc includes a radially symmetrical surface, said radially symmetrical surface normal to a rotational axis of said seed disc, said radially symmetrical surface disposed radially outward of said seed apertures, said seed apertures elevated relative to said radially symmetrical surface along a direction parallel to said rotational axis.   
     
     
       28. The seed meter of claim 15, wherein said seed disc includes a radially symmetrical surface, said radially symmetrical surface normal to a rotational axis of said seed disc, said radially symmetrical surface disposed radially outward of said seed apertures, said seed apertures elevated relative to said radially symmetrical surface along a direction parallel to said rotational axis.