Patent Publication Number: US-2022232756-A1

Title: Seed meter assembly and metering member for small grains

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a divisional of U.S. patent application Ser. No. 16/409,418 filed on May 10, 2019, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     The present disclosure relates to a seeding machine for metering seeds to be planted, such as a row crop planter for agricultural applications. More specifically, the present disclosure relates to a seed meter assembly having a metering member, such as a seed disk, for singulating small grains such as wheat, barley, rice, oats, etc. 
     SUMMARY 
     The disclosure provides a seed meter assembly including a metering member configured for improving the speed with which the metering member can pick up certain small grains such as wheat and other similarly shaped seeds (barley, rice, oats, etc.). Growers often plant wheat at relatively high rates such as a 1,000,000 seeds per acre compared with lower rates of 200,000 seeds per acre for soybeans or 36,000 seeds per acre for corn. The speed at which the metering member can adhere seeds as it passes through a seed pool depends at least in part on the direction of rotation of the metering member relative to the geometry of the metering member, which may include apertures and cells of a certain shape surrounding each aperture. This speed can be expressed as surface-feet-per-second (SFPS), i.e., the number of linear feet that a location on the rotating metering member travels in one second. There are a number of variables that contribute to increasing this effective SFPS, such as distance between apertures, the number of rows of apertures (each of which contributes individually to the effective, or overall, SFPS), the number of apertures in each row, sources of agitation in the seed pool, and the geometry of the metering member in the vicinity of the apertures (e.g., cell shape). 
     In one aspect, the disclosure provides a seed meter assembly including a motor, a seed reservoir configured to support seeds, and a metering member having a seed side facing the seed reservoir and a non-seed side opposite the seed side. The motor is configured to drive the metering member in a rotational direction moving from upstream towards downstream. The metering member includes a plurality of apertures extending from the seed side to the non-seed side for picking up seeds from the seed reservoir under the influence of a pressure differential, and a cell diverging from an aperture of the plurality of apertures towards the seed side to define a surface recessed therefrom, the cell configured to receive one of the seeds, the cell being elongated between a first end defining a furthest extent of the cell in an upstream direction and a second end defining a furthest extent of the cell in a downstream direction. The aperture of the plurality of apertures is disposed closer to the second end than to the first end. 
     In another aspect, the cell has a semi-circular outline combined with a semi-oval or semi-elliptical outline. 
     In another aspect, the semi-circular outline is disposed generally around a first half of the aperture and the semi-oval or semi-elliptical outline is disposed generally around a second half of the aperture. 
     In another aspect, the surface curvedly extends from the first end to the aperture and curvedly extends from the aperture to the second end. 
     In another aspect, the surface includes a steeper recessing slope adjacent the first and second ends than adjacent the aperture. 
     In another aspect, the seed metering includes at least one brush disposed adjacent the seed side of the metering member and configured to sweep across the cell from the second end to the first end as the metering member rotates. 
     In another aspect, the at least one brush includes a brush disposed proximate an upper boundary of the seed reservoir. 
     In another aspect, the at least one brush includes a brush disposed above the seed reservoir configured to return excess seeds to the seed reservoir by agitation and gravity. 
     In another aspect, the metering member is operable to transport at least 70 seeds per second from the seed pool to a delivery conduit extending from the metering member towards the ground. 
     In another aspect, the metering member is operable to transport 200 or more seeds per second from the seed pool to a delivery conduit extending from the metering member towards the ground. 
     In another aspect, the metering member is operable to transport 590 to 670 seeds per second from the seed pool to a delivery conduit extending from the metering member towards the ground. 
     In another aspect, the metering member is operable to transport 610 to 650 seeds per second from the seed pool to a delivery conduit extending from the metering member towards the ground. 
     In another aspect, the plurality of apertures includes a plurality of rows of apertures. 
     In another aspect, the cell is shaped to receive wheat. 
     In yet another aspect, the disclosure provides a seed metering member rotatable about an axis in a rotational direction moving from upstream towards downstream. The seed metering member includes a seed side configured to face a seed reservoir and a non-seed side opposite the seed side, a plurality of apertures for picking up seeds under the influence of a pressure differential, and a plurality of cells, each cell diverging from one aperture of the plurality of apertures towards the seed side to define a surface recessed from the seed side. Each cell is configured to receive one of the seeds, each cell further being elongated between a first end defining a furthest extent of the cell in an upstream direction and a second end defining a furthest extent of the cell in a downstream direction. The one aperture is disposed closer to the second end than to the first end. Each cell includes a recessed surface curvedly extending from the first end to the one aperture and curvedly extending from the one aperture to the second end. 
     In another aspect, the cell has a semi-circular outline combined with a semi-oval or semi-elliptical outline, wherein the semi-circular outline is disposed generally around a first half of the aperture and the semi-oval or semi-elliptical outline is disposed generally around a second half of the aperture. 
     In yet another aspect, the disclosure provides a seed meter assembly including a motor, a seed reservoir configured to support seeds, and a metering member having a seed side facing the seed reservoir and a non-seed side opposite the seed side. The motor is configured to drive the metering member in a rotational direction. The metering member includes a plurality of rows of apertures for picking up seeds from the seed reservoir under the influence of a pressure differential. The seed meter assembly also includes a kickout wheel assembly disposed on the non-seed side of the metering member for clearing the plurality of rows of apertures. The kickout wheel assembly includes a plurality of kickout wheels independently journaled for rotation, each kickout wheel of the plurality of kickout wheels having projections configured to mesh with a respective one row of the plurality of rows of apertures and to rotate at different speeds as the metering member rotates. 
     In another aspect, each kickout wheel of the plurality of kickout wheels has a different diameter and a different number of projections. 
     In another aspect, the number of apertures in each row of the plurality of rows of apertures is different, and wherein the number of projections on each kickout wheel of the plurality of kickout wheels is different. 
     In another aspect, the number of apertures in each row of the plurality of rows of apertures increases as the plurality of rows extends radially outwards on the metering member, and wherein the number of projections on each kickout wheel of the plurality of kickout wheels increases as the kickout wheels extend radially outwards with respect to the metering member. 
     Any of the above referenced aspects of the disclosure can be combined with any one or more of the above referenced aspects of the disclosure. 
     In addition, other aspects of the disclosure will become apparent by consideration of the detailed description and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a seeding machine. 
         FIG. 2  is a top view of the seeding machine of  FIG. 1  coupled to a towing vehicle. 
         FIG. 3  is a right side view of a portion of a seed meter assembly and a seed tube for the seeding machine of  FIG. 1 . 
         FIG. 4  is a right side view of a portion of the seed meter assembly shown in  FIG. 3  with the right side housing removed. 
         FIG. 5  is a left side perspective view of a portion of the seed meter assembly shown in  FIG. 4  with a portion of the left side housing removed. 
         FIG. 6  is a left side perspective view of the metering member with brushes. 
         FIG. 7  is a cross-section of the seed meter assembly taken through line  7 - 7  in  FIG. 5  with seeds. 
         FIG. 8  is an enlarged view of a cell and aperture of the metering member of  FIG. 6 . 
         FIG. 9  is a front view of the cell and aperture of  FIG. 8 . 
         FIG. 10  is a right side perspective view of a portion of the seed meter assembly of  FIG. 3  having a kickout wheel assembly. 
         FIG. 11  is an exploded view of the kickout wheel assembly of  FIG. 10 . 
     
    
    
     DETAILED DESCRIPTION 
     Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of supporting other embodiments and of being practiced or of being carried out in various ways. 
       FIGS. 1-2  illustrate a seeding machine  10 , such as a row crop planter pulled by a vehicle  100 , such as a tractor ( FIG. 2 ). The seeding machine  10  has a frame  12  on which are mounted a plurality of individual row units  14 . Seed sources, such as storage tanks  13   a - 13   c,  hold seed that may be delivered, e.g., pneumatically, to a mini-hopper on each row unit  14  or directly to each row unit  14 . The storage tanks  13   a - 13   c  may be coupled to the row units  14  by way of conduits  20 , such as hoses, and a pressurized delivery apparatus (not shown). Each storage tank  13   a - 13   c  can be used to contain the same variety of seeds, or a different variety of seeds. For example, a first storage tank  13   a  may contain a first variety of seeds, a second storage tank  13   b  may contain a second variety of seeds, and a third storage tank  13   c  may contain a third variety of seeds. In other implementations, the storage tanks  13   a - 13   c  may contain the same variety of seeds, and need only employ a single storage tank. In other implementations, one, two, four, or more storage tanks may be employed. The varieties of seed may include small seeds or grains, such as wheat, barley, rice, oats, etc., or other small seeds or grains of a similar size. In other implementations, larger seeds of a similar shape may be employed. 
     Each row unit  14  has a frame  18  to which the components of the row unit  14  are mounted. For example, the frame  18  may carry furrow opening disks  21  for forming a furrow  15  with an open channel in the soil beneath the seeding machine  10  into which seed is deposited, as well as closing wheels (not shown) to close the furrow over the deposited seed in the furrow  15 . 
     As illustrated in  FIG. 3 , a seed meter assembly  16  having a housing  17  and a seed metering member  24  is coupled to each row unit frame  18 . The seed metering assembly  16  is coupled to one or more of the storage tanks  13   a - 13   c  by way of the conduits  20 . The metering member  24  takes seeds from a seed reservoir  28  supporting a seed pool  22  ( FIG. 4 ) and sequentially discharges single seeds S (metered seeds) for delivery one at a time (e.g., singulates and meters the seeds). The metering member  24  employs a negative air pressure differential (i.e., a vacuum), as will be described in greater detail herein, to adhere seeds to the metering member  24 , which can be in the form of a disk (as illustrated), or more generally a plate, a bowl, an internal drum meter, an external drum meter, etc., having apertures  26  that extend therethrough. The apertures  26  are generally arranged circumferentially about a meter axis A, substantially in a circle, proximate an outer edge of the metering member  24 . The apertures  26  are arranged in a plurality of rows  30   a - 30   d  arranged concentrically about the meter axis A. In the illustrated implementation, the plurality of rows includes a first row  30   a,  a second row  30   b,  a third row  30   c,  and a fourth row  30   d.  However, in other implementations, the plurality of rows  30   a - 30   d  may include only one row, only two rows, only three rows, five rows, or more rows. Preferably, the metering member  24  includes at least four rows  30   a - 30   d  in order to sufficiently increase the effective SFPS. In the illustrated implementation, each row of the plurality of rows  30   a - 30   d  includes a different number of apertures  26 . For example, the number of apertures  26  in each row  30   a - 30   d  increases as the rows increase in radial distance from the meter axis A. The apertures  26  are arranged close together in each row  30   a - 30   d  in order to increase the effective SFPS. In other implementations, the rows  30   a - 30   d  of apertures  26  may be arranged coaxially on a drum-style metering member. 
     The metering member  24  may be driven to rotate by a motor  32  (illustrated schematically in  FIG. 6 ), such as an electric motor. The motor  32  may include any other suitable drive mechanism, such as a transverse hex shaft driven by a ground wheel or electric or hydraulic motor and coupled to individual meters by chains or drive cables, etc. The motor  32  drives the metering member  24  to rotate in a rotational direction  34 , as illustrated by the arrow in  FIGS. 3-11 . The rotational direction  34  is defined by the shortest rotational distance from a top  36  of the metering member  24 , opposite the seed reservoir  28 , towards the delivery conduit  52 , which will be described in greater detail below. In the illustrated implementation, the metering member  24  is driven counterclockwise when viewing a non-seed side  38  ( FIG. 3 ) and clockwise when viewing a seed side  40  ( FIG. 5 ). The motor  32  rotates the metering member  24  at a speed that corresponds with transport of  30  or more seeds per second to the furrow  15  (e.g., 30 to 700 seeds per second), which may be referred to herein as a singulation rate of the seed meter assembly  16 , or of the metering member  24 . More specifically, the singulation rate may be 70 or more seeds per second, and even more specifically may be 200 or more seeds per second. Even more specifically, the singulation rate is 200 to 700 seeds per second. For example, the singulation rate may be 300 to 700 seeds per second, 400 to 700 seeds per second, 500 to 700 seeds per second, or 600 to 700 seeds per second. Even more specifically, the singulation rate may be 590 to 670 seeds per second. Even more specifically still, the singulation rate may be 610 to 650 seeds per second. These singulation rates are higher than typical singulation rates of metering members designed for other types of seed, such as corn, beans, and soy. Both speed of the metering member and the number of apertures in the metering member contribute to the singulation rate, with higher speeds and higher number of apertures promoting higher singulation rates. 
     With reference to  FIGS. 4-5 , the seed reservoir  28  containing the seed pool  22  is disposed on the seed side  40  of the metering member  24  at a lower portion thereof, and is connected to one or more of the storage tanks  13   a - 13   c  to receive seeds therefrom by way of the conduits  20 . Thus, the seed side  40  faces the seed reservoir  28 . A pressure differential is applied across the metering member  24  from the seed side  40  of the metering member  24  to the non-seed side  38  ( FIG. 3 ) of the metering member  24 , through the apertures  26 . The pressure differential may be applied by a pump (not shown), as is understood in the art. In the illustrated implementation, a negative pressure, or vacuum applied on the non-seed side  40  provides a suction force that adheres a seed S to the seed side  40  of the metering member  24  at the apertures  26 . The pressure differential is applied in a vacuum zone  42  defined by a vacuum-seal housing  44  illustrated in  FIG. 3  across a portion of the metering member  24 , and thus across some, but not all of the apertures  26 . The vacuum zone  42  is defined by the vacuum-seal housing  44  that engages the non-seed side  38  of the metering member  24 . In the illustrated implementations, the pressure differential draws seeds into adherence with the seed side  40  of the metering member  24 . In order to release a seed S, one seed at a time (e.g., to meter, or singulate, the seeds), the vacuum is terminated at a desired release position in an area referred to herein as a vacuum cutoff  46 . The vacuum cutoff  46  is a region disposed immediately adjacent the vacuum-seal housing  44  in a circumferential direction with respect to the meter axis A and is not under the influence of the pressure differential. Mechanical assistance, such as a kickout wheel assembly  48  (as will be described in greater detail), is utilized to clear (e.g., to push) the seed off the metering member  24 . The kickout wheel assembly  48  described herein may be disposed outside of the vacuum zone  42 , e.g., in a non-vacuum zone  50 . In yet other implementations, other types of metering members  24  for metering/singulating the seeds may be employed. In further implementations, rather than applying a vacuum to the non-seed side  38  of the metering member  24 , a positive pressure may be applied to the seed side  40  to adhere the seeds S to the metering member  24 . It should be understood that positive and negative are relative terms. As such, the terms “positive pressure” and “negative pressure” are meant to describe relative pressures of a pressure differential. For example, a positive pressure is one that is higher than its surroundings (e.g., higher than atmospheric pressure or than another pressure in the seeding machine  10 ), and a negative pressure is one that is lower than its surroundings (e.g., lower than atmospheric pressure or than another pressure in the seeding machine  10 ). 
     With reference to  FIGS. 3-4 , a delivery conduit  52 , or tube, is disposed in the non-vacuum zone  50  for receiving singulated, metered seeds S from the metering member  24 . The delivery conduit  52  may be configured to direct singulated, metered seeds S from the metering member  24  to the furrow  15  by gravity. In other implementations, the delivery conduit  52  may be operatively coupled to a source of air pressure, such as a pump (not shown), for directing the singulated, metered seeds S to the furrow  15  by pressure differential. 
     With reference to  FIGS. 4-7 , a bracket  54  disposed on the seed side  40  of the metering member  24  fixedly supports a plurality of brushes  56   a - 56   d  extending into engagement with the seed side  40  of the metering member  24 . The bracket  54  is mounted fixedly, e.g., proximate the metering axis A, such that the metering member  24  rotates relative to the bracket  54  and the bracket  54  remains stationary. The bracket  54  may include a hub  58  concentric with the metering axis A, which may include a bearing or a bearing surface, about which the metering member  24  rotates. The bracket  54  includes one or more feet  60   a - 60   c  that brace the bracket  54  against the seed side  40  of the movable metering member  24 . In the illustrated implementation, the bracket  54  includes a first foot  60   a  and a second foot  60   b  in engagement with the metering member  24 , e.g., by respective bearing surfaces, though other quantities of feet may be employed in other implementations. The bracket  54  is spring-loaded into engagement with the metering member  24  by way of a biasing member  62  on the seed side. The biasing member  62  is fixedly mounted to the housing  17  at a mounting point  64 , e.g., by a fastener, such that the biasing member  62  is placed in compression between the housing  17  and the bracket  54 . The biasing member  62  is formed as a plate, e.g., from a sheet of material such as metal or other suitable material, and includes a plurality of arms  66   a - 66   c  extending away from the mounting point  64 , e.g., in radial directions. In the illustrated implementation, the biasing member  62  includes a first arm  66   a,  a second arm  66   b,  and a third arm  66   c,  but may include a single arm, two arms, or more than three arms in other implementations. The first arm  66   a  is coupled to the bracket  54  proximate the hub  58 , and the second and third arms  66   b,    66   c  are coupled to the bracket  54  at different locations about the hub  58 . The plurality of arms  66   a - 66   c  are mounted in flexion by the compression arrangement described above. Thus, the bracket  54  and the plurality of brushes  56   a - 56   d  carried by the bracket  54  are spring-loaded into engagement with the seed side  40  of the metering member  24  by the biasing member  62 . 
     In the illustrated implementation, the plurality of brushes  56   a - 56   d  includes a first brush  56   a,  a second brush  56   b,  a third brush  56   c,  and a fourth brush  56   d.  The plurality of brushes  56   a - 56   d  each extends across all of the rows  30   a - 30   d  of apertures  26 . The first brush  56   a  is disposed at, or defines, a top of the seed pool  22  proximate an upper boundary  68  of the seed reservoir  28 . The fourth brush  56   d  is disposed adjacent the delivery conduit  52 . The second and third brushes  56   b,    56   c  are disposed between the first and fourth brushes  56   a,    56   d  and above the seed pool  22  (i.e., above the seed reservoir  28 ) with respect to a gravitational direction (vertical in all drawings). Each of the brushes  56   a - 56   d  includes a brush member  70  ( FIG. 7 ), such as a plurality of bristles, extending from a brush base  72 , the brush member  70  extending into engagement with the seed side  40  of the metering member  24 . In other implementations, each brush member  70  may also or alternatively include a single brush block, such as a foam block, or other block of flexible material, extending from the brush base  72  and into engagement with the seed side  40  of the metering member  24 . In yet other implementations, each brush member  70  may include a wiper, such as a rubber wiper, or other suitable material. Thus, the brush member  70  may be formed from a flexible material. Other suitable types of brush members  70  may be employed. 
     With reference to  FIGS. 6-9 , each aperture  26  is fluidly coupled to, and surrounded by, a cell  74  diverging therefrom toward the seed side  40  to define a surface  90  ( FIGS. 8-9 ) recessed from the seed side with the aperture  26  through the recessed surface  90 . Thus, the cells  74  are recessed from the seed side  40  of the metering member  24  towards the non-seed side  38 . At least one of the apertures  26  is surrounded by the cell  74  diverging therefrom, and in the illustrated implementation all of the apertures  26  are surrounded by a respective one of the cells  74 . In the illustrated implementation, each cell  74  is substantially identical in shape and size to the next, such that the shape and size of only one of the cells  74  need be described. With particular reference to the orthogonal view of the cell  74  in  FIG. 9 , the cell  74  includes an elongated shape, elongated in the rotational direction  34  of the metering member  24 . The elongated shape of the cell  74  extends between a first end  76  and a second end  78 , the first end  76  being disposed upstream of the respective aperture  26  relative to the rotational direction  34 , and the second end  78  being disposed downstream of the aperture  26  relative to the rotational direction  34 . The first end  76  defines a furthest extent of the cell  74  in the upstream direction, and the second end  78  defines a furthest extent of the cell  74  in the downstream direction. The first end  76  is narrower than the second end  78  such that the shape of the cell  74  is tapered from the second end  78  towards the first end  76 . In other words, the shape of the cell  74  is tapered in a direction opposite the rotational direction  34  of the metering member  24  (i.e., the upstream direction). Thus, the wider portion of the cell  74  (i.e., the second end  78 ) leads in the rotational direction  34 . Furthermore, the aperture  26  is disposed closer to the second end  78  than to the first end  76  of the cell  74 . Thus, the aperture  26  also leads in the rotational direction  34 . 
     A leading portion  80  of the cell  74  proximate the second end  78  of the cell  74  may have a generally semi-circular recessed shape extending partially (e.g., about halfway or 180 degrees) around the aperture  26 , while a trailing portion  82  of the cell  74  proximate the first end  76  of the cell  74  may have a generally tapered and/or elongated (e.g., generally semi-oval or semi-elliptical) recessed shape extending partially around (e.g., around the other half of) the aperture  26 . More specifically, the cell  74  has an outline  84  defined by an intersection of the cell  74  with the seed side  40  of the metering member  24 . The outline  84 , or edge of the recessed cell  74  intersecting the seed side  40 , generally includes the shape of a semi-circle  86  combined with a semi-oval or semi-ellipse  88 . The terms “generally” and ‘about” should be understood herein to mean approximately or nearly. The semi-circle  86  extends about halfway around the aperture  26  and the semi-oval or semi-ellipse  88  extends, in an elongated fashion with respect to the rotational direction  34 , about halfway around the aperture  26  opposite the semi-circle  86 . The cell  74  recesses away from the seed side  40  of the metering member  24  towards the non-seed side  38  of the metering member  24  in a bowl-like, or parabolic-like, shape as can be seen in the cross-section of  FIG. 7 . The bowl-like, or parabolic-like, shape is concave and has a slope (as can be seen in the cross-section of  FIG. 7 ) that decreases in magnitude from the seed side  40  toward the non-seed side  38  and is zero (i.e., has a vertex) at its intersection with the aperture  26 . In other words, the slope of the recessed surface  90  is steeper adjacent the seed side  40  than adjacent the aperture  26 . Also apparent in the cross-section of  FIG. 7  is the asymmetry of the cell shape discussed above, i.e., the bowl-like, or parabolic-like, shape is more elongated in the trailing portion  82  of the cell  74  than in the leading portion  80  of the cell  74 . The cell  74  is deep (i.e., recessed) enough to cause seeds S to be scooped toward the aperture  26  at the vertex of each cell  74  but shallow enough that if there is more than one seed S attracted to each cell  74 , the excess seeds are likely able to be perturbed away, e.g., by the brushes  56   a - 56   d.    
     As illustrated in the cross section of  FIG. 7 , which is taken through the aperture  26  generally in a longitudinal direction E of elongation of the cell  74  (i.e., generally the rotational direction  34  of the metering member  24 ), the cell  74  includes the recessed surface  90  that is curved rather than flat. As shown, a trailing portion  90   a  of the recessed surface  90  curvedly extends in cross section from the first end  76  to the one of the plurality of apertures  26  and a leading portion  90   b  of the recessed surface  90  curvedly extends in cross section from the one of the plurality of apertures  26  to the second end  78 . In a cross section (not shown) taken through the aperture  26  perpendicular to the cross-section shown in  FIG. 7  (i.e., perpendicular to the rotational direction  34 , or in a radial direction F with respect to the metering axis A), the recessed surface  90  is also entirely curved rather than flat or partially flat (as is illustrated by the shading in  FIGS. 8-9 ). 
     As such, the cell  74  and aperture  26  are configured with respect to the rotational direction  34  to have a backsweeping geometry, i.e., for encouraging the seed S to lay down in the cell  74  as illustrated in  FIG. 7  with a first portion of the seed S adhered to the aperture  26  by the pressure differential and received in the leading portion  80  proximate the second end  78  of the cell  74 , and with a second portion of the seed S laid down and received in the elongated, tapered trailing portion  82  of the cell  74  proximate the first end  76 . This “scoop” cell shape increases the number of seeds S that are brought close to each aperture  26  as it passes quickly through the seed pool  22  (as opposed to tear-drop-shaped cells having flat recessed surfaces employed, for example, with soybeans). The brushes  56   a - 56   d  singulate the seeds S by removing seeds in excess of one per cell  74  and encourage one seed S per cell  74  to lie down in the cell  74  as described herein. Given the rotational direction  34  of the metering member  24 , the brushes  56   a - 56   d  sweep each cell  74  from the leading portion  80 , including the wider second end  78 , towards the trailing portion  82 , including the narrower first end  76 . The trailing portion  82  is longer in the rotational direction  34  than the leading portion  80 . 
       FIGS. 10-11  illustrate the kickout wheel assembly  48 , which is disposed on the non-seed side  40  of the metering member  24 . The kickout wheel assembly  48  includes a plurality of kickout wheels  92   a - 92   d  corresponding to the number of rows of apertures  26 . As such, the illustrated implementation includes four rows of apertures  26  and four kickout wheels  92   a - 92   d  including a first kickout wheel  92   a,  a second kickout wheel  92   b,  a third kickout wheel  92   c,  and a fourth kickout wheel  92   d.  Each kickout wheel  92   a - 92   d  includes an annular hub  94  and a plurality of projections  96  extending radially from the hub  94 . The hub  94  may include a bearing, such as a ball bearing, a needle bearing, a bushing, or any other suitable bearing. The projections  96  each include a shoulder  98  and a tip  102 , the tip  102  projecting from the shoulder  98  in a radial direction with respect to the annular hub  94  (i.e., with respect to a bearing axis B which will be described in greater detail). In other implementations, the plurality of projections  96  may have different shapes and configurations. Each projection  96  is configured to extend at least partially into the respective aperture  26 . In some implementations the projection  96  may extend through the respective aperture  26 . The projections  96  encourage clearing seed remnants out of the apertures  26  after, or concurrently with, the transfer of seeds S from the metering member  24  to the delivery conduit  52  so the metering member  24  is clear for the next revolution. More specifically, the shoulders  98  mesh with the metering member  24  to drive the respective kickout wheel  92   a - 92   d,  wherein the tips  102  clear the apertures  26 . 
     Each wheel of the plurality of kickout wheels  92   a - 92   d  includes a different diameter D and a different number of projections  96 . Specifically, the diameter D1-D4 of the kickout wheels  92   a - 92   d  increases from the first to the fourth kickout wheel  92   a - 92   d  as the kickout wheels extend radially away from the metering axis A. Similarly, the number of projections  96  increases from the first to the fourth kickout wheel  92   a - 92   d  as the kickout wheels extend radially away from the metering axis A. This configuration allows the plurality of kickout wheels  92   a - 92   d  to be arranged coaxially about the bearing axis B for independent rotation thereabout while each kickout wheel  92   a - 92   d  engages the respective row  30   a - 30   d,  each having a different number of apertures  26 . That is, each kickout wheel  92   a - 92   d  is independently journaled from the next about the common bearing axis B such that each kickout wheel  92   a - 92   d  can rotate at a different speed (e.g., revolutions per minute) to mesh with its respective row of apertures  30   a - 30   d.    
     The plurality of kickout wheels  92   a - 92   d  are journaled on an axle  104  defining the bearing axis B. The axle  104  is configured as an elongated pin or rod extending along the bearing axis B from a pivotably mounted yoke  106 . The yoke  106  is pivotably mounted about a yoke axis C and biased by a biasing member  108  such that the kickout wheels  92   a - 92   d  are biased into engagement with the non-seed side  38  of the metering member  24 . The biasing member  108  is disposed between the yoke  106  and the housing  17  and engages the yoke  106  and the housing  17 . The biasing member  108  engages the yoke  106  on a side of the yoke axis C on which the axle  104  is disposed so as to bias the axle  104  towards the metering member  24 . In the illustrated implementation, the biasing member  108  includes a spring, such as a coil spring. However, in other implementations, the biasing member  108  may include other suitable forms, such as a torsion spring, a leaf spring, an elastic member, etc. 
     In operation, the metering member  24  rotates about the metering axis A at a relatively high speed through the seed pool  22  as the rows  30   a - 30   d  of apertures  26  pick up seeds S from the seed pool by virtue of the pressure differential. The brushes  56   a - 56   d  singulate the seeds S as the metering member  24  rotates and are disposed above the seed pool  22 , causing excess seeds (in excess of one per aperture  26 ) to fall back down into the seed pool  22 . The shape of the cells  74  facilitates scooping of seeds S from the seed pool  22  and facilitates adherence of one seed S per aperture  26  in cooperation with the plurality of brushes  56   a - 56   d.  Employing the plurality of rows  30   a - 30   d  of apertures  26  increases the rate of seeds (seeds per second) that are delivered to the furrow  15  relative to metering member  24  diameter. Employing a different number of apertures  26  in each of the plurality of rows  30   a - 30   d  allows for more apertures  26  to be disposed on a single metering member  24  (compared with metering members that employ the same number of apertures in each row), which may be referred to as improved aperture density. In order to clear rows  30   a - 30   d  of apertures  26  having different numbers of apertures  26 , the kickout wheel assembly  48  includes independently journaled kickout wheels  92   a - 92   d  each independently rotatable and having a different number of projections  96 . 
     Thus, the disclosure provides, among other things, a seed meter assembly  16  having a multi-row metering member  24  for small seed applications in which a high rate of seed output is desired. The plurality or rows  30   a - 30   d,  aperture  26  density, cell  74  geometry, plurality of brushes  56   a - 56   d,  and kickout wheel assembly  48  facilitate operation at high speeds and the high rate of seed output. Various features and advantages of the disclosure are set forth in the following claims.