Patent Publication Number: US-2021168993-A1

Title: Seed meter

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation patent application of U.S. patent application Ser. No. 16/017,534, which was filed on Jun. 25, 2018, the entire disclosure of which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     Embodiments of the present invention are directed generally to a seed meter. More particularly, embodiments of the present invention relate to a seed meter that can be used to meter seed from an agricultural seed planting machine. 
     BACKGROUND OF THE INVENTION 
     Agricultural seed planting machines often incorporate the use of seed meters to aid in planting seed onto and/or into the ground. Such seed meters are configured to meter seed from a seed bin down onto and/or into the ground. Generally, a seed planting machine will include a transmission system for transmitting power (e.g., rotation) to the seed meters to facilitate such metering. The transmission system will often be powered by one or more rotating components, such as the seed planting machine&#39;s wheels, rollers, disc assemblies, or the like. During use of the seed planting machine, the rotating components generally rotate in response to movement of the machine. For example, if a seed planting machine travels in a first direction, the rotating components will similarly rotate in a first direction. Alternatively, if the seed planting machine travels in a second direction, the rotating components will similarly rotate in a second direction. Because the seed meters of the seed planting machines are directly linked to the rotating components via the transmission systems, the seed meters will be driven regardless of the direction in which the seed planting machines are moving. 
     However, many previously-used seed meters are only configured to be driven in a single direction. As such, these seed meters can be damaged if they are driven in an opposite direction than for which they were designed. Notwithstanding such limitations, it is often necessary to move the seed planting machines in more than a single direction. It would be desirable to move the seed planting machines in more than one direction without damaging the seed meters. 
     In addition, many previously-used seed meters were configured to meter only a specific type or a specific size of seed. If the previously-used seed meters encountered a large obstacle, such as a rock or other debris, such a large obstacle could enter the seed meter and cause damage to or interrupt operation of the seed meter. As such, it would be desirable for seed meters to encounter and process large obstacles without causing damage to or otherwise interfering with operation of the seed meters. 
     SUMMARY OF THE INVENTION 
     In one embodiment of the present invention, there is provided a seed planting machine for dispensing seed onto and/or into the ground. The seed planting machine comprises a seed bin configured to hold seed, and at least one seed meter associated with the seed bin and configured to meter seed from the seed bin. The seed meter comprises a housing at least partially enclosing an interior space, with the housing including a top surface defining a seed inlet. The housing further includes a seed outlet. The seed meter additionally comprises a metering wheel positioned within the interior space of the housing. Rotation of the metering wheel provides for seed to travel through the seed meter from the seed inlet to the seed outlet. The seed meter further includes a retractable seed guard positioned within the interior space of the housing and configured to be selectively configured in an operating configuration and in a retracted configuration. In the operating configuration the seed guard is configured to restrict excess seed from passing through the seed meter. In the retracted configuration, the seed guard is configured to permit obstacles to pass through the seed meter. 
     In another embodiment of the present invention, there is provided a seed meter for dispensing seed. The seed meter comprises a housing at least partially enclosing an interior space. The housing includes a top surface defining a seed inlet, and further includes a seed outlet. The seed meter additionally includes a metering wheel positioned within the interior space of the housing. The metering wheel comprises a plurality of fluted sections on an exterior radial surface of the metering wheel. The metering wheel is configured to carry seed through said housing regardless of whether the metering wheel is rotating in a first direction or in a second direction. The seed meter further includes a pair of retractable seed guards positioned within the interior space of the housing. The seed guards are each configured to be selectively configured in an operating configuration and in a retracted configuration. In the operating configuration the seed guards are configured to prevent excess seed from passing through the seed meter, and in the retracted configuration the seed guards are configured to permit obstacles to pass through the seed meter. 
     In yet another embodiment of the present invention, there is provided a method for planting seed with a seed planting machine. The method comprises a step of providing one or more seed meters in association with a seed bin. The seed meters each include a housing that presents a seed inlet and a seed outlet, and a metering wheel positioned within the housing. The method includes the additional step of travelling in a first direction with the seed planting machine. During such travelling, the step further includes metering seed from the seed bin via the metering wheel rotating in a first direction. The method includes a further step of travelling in a second direction with the seed planting machine. During such travelling, the step further includes metering seed from the seed bin via the metering wheel rotating in a second direction. 
     This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Other aspects and advantages of the present invention will be apparent from the following detailed description of the embodiments and the accompanying drawing figures. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       Embodiments of the present invention are described herein with reference to the following drawing figures, wherein: 
         FIG. 1  is a front, side, and top perspective view of a seed meter according to embodiments of the present invention; 
         FIG. 2  is a front, side, and bottom perspective view of the seed meter of  FIG. 1 ; 
         FIG. 3  is a front and side exploded view of the seed meter of  FIGS. 1 and 2 ; 
         FIG. 4  is a rear, side perspective view of a seed planting machine according to embodiments of the present invention; 
         FIG. 5  is a top, side perspective view of the seed planting machine of  FIG. 4 , with a portion of the seed planting machine cutaway to illustrate a plurality of the seed meters from  FIGS. 1-3 ; 
         FIG. 6  is an enlarged view of a portion of the seed planting machine from  FIGS. 4-5 , particularly illustrating the portion circled in dashed line in  FIG. 5 ; 
         FIG. 7  is a perspective cross sectional view of a portion of the seed planting machine from  FIGS. 4-6 , particularly illustrating a seed bin, a seed meter secured to a bottom of the seed bin, and a seed channel positioned below the seed meter; 
         FIG. 8  is an elevation view of the cross section from  FIG. 7 , particularly illustrating the seed meter metering seed from the seed bin, and with the seed meter including a pair of seed guards each configured in a normal operating configuration; 
         FIG. 9  is another elevation view of the cross section of  FIGS. 7 and 8 , particularly illustrating the seed bin containing a large obstacle; 
         FIG. 10  is another elevation view of the cross section of  FIGS. 7-9 , particularly illustrating the large obstacle entering the seed meter, and with one of the seed guards being shifted to a retracted configuration; 
         FIG. 11  is another elevation view of the cross section of  FIGS. 7-10 , particularly illustrating the large obstacle exiting the seed meter; 
         FIG. 12  is an enlarged cross section of the seed meter of  FIGS. 1-3 and 7-11  attached to the bottom of the seed bin, with a front seed guard configured in a retracted configuration and a rear seed guard configured in a normal operating configuration; 
         FIG. 13A  is top perspective view of a seed meter according to embodiments of the present invention, illustrating a metering wheel positioned completely within a housing of the seed meter; 
         FIG. 13B  is a top perspective view of the seed meter of  FIG. 13A , illustrating the metering wheel partly positioned within the housing; and 
         FIG. 13C  is a top perspective view of the seed meter of  FIGS. 13A and 13B , illustrating the metering wheel positioned completely outside the housing. 
     
    
    
     The drawing figures do not limit the present invention to the specific embodiments disclosed and described herein. The drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the invention. 
     DETAILED DESCRIPTION 
     The following detailed description of the present invention references various embodiments. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments can be utilized and changes can be made without departing from the scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense. The scope of the present invention is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled. 
     Broadly, embodiments of the present invention are directed to a seed meter  10 , as illustrated in  FIGS. 1-3 , which can be used to meter or dispense seed from a seed planting machine. The seed meter  10  may comprise a housing  12  that encloses an interior space and is configured to hold a fluted metering wheel  14 . The metering wheel  14  is perhaps best shown in  FIG. 3 . As will be described in more detail below, the metering wheel  14  is configured to rotate so as to facilitate the dispensing of seed from the seed planting machine (not shown in  FIGS. 1-3 ). The metering wheel  14  may be formed as a wheel or a drum with a plurality of fluted sections  16  formed along an exterior radial surface of the metering wheel  14 . The fluted sections  16  may extend generally along the entire lateral width of the metering wheel  14  in a direction that is generally parallel with an axis of rotation of the metering wheel  14 . Each of the fluted sections  16  may, in some embodiments, be substantially identical. In certain embodiments, each of the fluted sections  16  may have a uniform shape or cross-section, with such uniformity extending along the length of the fluted section  16 . In addition, the fluted sections  16  may be uniformly spaced apart from adjacent fluted sections  16 , such that the fluted sections  16  are uniformly spaced circumferentially around the exterior radial surface of the metering wheel  14 . Given such positioning and uniformity of the fluted sections  16 , the metering wheel  14  of embodiments of the present invention is suitably configured to meter seed when rotating in either rotational direction (i.e., clockwise or counter-clockwise). 
     In some embodiments, the housing  12  may comprise an upper portion  20  and a lower portion  22 . Such upper and lower portions  20 ,  22  may, in some embodiments, be separable from each other but secured together via vertically-orientated fasteners. The upper portion  20  may, as perhaps best shown in  FIG. 1 , include a top surface  23  that defines a seed inlet  24 , which may be in the form of an opening or a portal through which seed may pass to enter the interior space of the housing  12 , as will be discussed in more detail below. In certain embodiments, the upper portion  20  may, as best illustrated in  FIG. 3 , comprise a pair of lateral side elements  26 . In some embodiments, the side elements  26  may be separable from each other but secured together via horizontally-oriented fasteners. The lower portion  22  may, as shown in  FIG. 2 , have a funnel-type shape that extends downward to define a seed outlet  28 , which may be in the form of an opening or a portal through which seed may pass to exit the housing  12 . 
     As will be described in more detail below, one or more seed meters  10  may be used on a seed planting machine to facilitate the precise volumetric dispensing of seed from the seed planting machine, such that a precise amount of seed can be deposited in the ground over which the seed planting machine is traveling.  FIG. 4  illustrates an exemplary seed planting machine  30  that may use the seed meters  10  of embodiments of the present invention.  FIGS. 5 and 6  illustrate a plurality of such seed meters  10  incorporated in the seed planting machine  30 . 
     As shown in  FIGS. 7 and 8 , each seed meter  10  can be secured (e.g., via one or more vertically-extending fasteners) to a bottom portion of a seed bin  32  of the seed planting machine  30 . In general operation of the seed planting machine  30 , the seed bin  32  will be filled with seed that is to be dispensed from the seed planting machine  30 . With reference to  FIG. 8 , as the seed planting machine  30  (not shown in  FIG. 8 ) travels over the ground, the metering wheel  14  of a seed meter  10  is caused to rotate within its housing  12 . During such rotation, which may be either clockwise or counterclockwise, seed will enter the housing  12  through the seed inlet  24  under the force of gravity. The upper portion  20  of the seed meter  10  will direct seed to the metering wheel  14 , such that a volumetric amount of seed will be captured within individual fluted sections  16  of the metering wheel  14  as the metering wheel  14  rotates. Certain embodiments may provide for the fluted sections  16  to be sized sufficiently (i.e., have an appropriate depth) such that, as the metering wheel  14  rotates, the seed captured within the fluted sections  16  will be positioned completely (or nearly completely) down within the fluted sections  16 . As a result, the metering wheel  14  is capable of rotating, and carrying seed, unrestricted past the top surface  23  of the upper section  20  of the housing  12 . In some embodiments, as will be described in more detail below, the seed meters  10  may comprise retractable seed guards  42  positioned under the top surface  23  of the upper section  20  of the housing  12 . In such embodiments, each seed meter  10  may be configured such that the metering wheel  14  is capable of rotating, and carrying seed, unrestricted past the seed guards  42 . As such, the metering wheel  14  can continue to rotate and carry the seed around in an arcuate manner until the seed is dropped from the metering wheel  14  under the force of gravity to fall out of the housing  12  via the seed outlet  28  presented by the lower portion  22  of the housing  12 . As illustrated in  FIGS. 7 and 8 , the seed planting machine  30  may include a seed channel  43  for directing the seed from the seed meter  10  out of the seed planting machine  30  onto and/or into the ground. In some embodiments, the seed planting machine  30  may include individual seed planting units (not shown in the drawings) at a lower end of the seed channel  43  for injecting seed onto and/or into the ground. 
     During operation of seed planting machines, such as seed planting machine  30 , it is not uncommon for large obstacles, such as rocks or other debris, to be present in the seed bin  32  that feeds the seed meters  10 . An exemplary large obstacle, in the form of a rock, is illustrated within the seed bin  32  of  FIG. 9 , which is feeding seed into the seed meter  10 . Large obstacles entering previously-used seed meters were problematic, because such large obstacles were known to cause damage to such seed meters (by physically damaging components of the seed meters, e.g., such as the metering wheel) and/or by jamming or otherwise interrupting the operation of the seed meters. However, the seed meter  10  of embodiments of the present invention overcomes such problems through the use of retractable seed guards  42 , as illustrated in  FIGS. 3, 8-12 . 
     In more detail, each seed meter  10  may include a pair of seed guards  42  positioned within the housing  12 . As perhaps best illustrated in  FIG. 12 , the seed meters  10  may include a seed guard  42  in each of a front portion and a rear portion of the interior space of the housing  12 . As used herein, the directional term “front” or “forward” is illustrated by a leftward direction in  FIGS. 8-12 . Correspondingly, the directional term “rear,” “back,” or “rearward” is illustrated by the rightward direction in  FIGS. 8-12 . 
     As shown in  FIGS. 3 and 12 , the seed guards  42  may each comprise a rectangular base section  44  and a tip section  46 . The tip section  46  may continuously reduce its cross-sectional width from the base section  44  to a narrow distal end of the tip section  46 . In some embodiments, a bottom surface of the tip section  46  may have an arcuate curvature that generally corresponds with (or is at least nominally larger than) the curvature of the metering wheel  14 . As such, the metering wheel  14  can rotate with the seed guards  42  being positioned very closely above the metering wheel  14 . In general, as shown in  FIG. 12 , the seed guards  42  may be positioned within the interior space of the housing  12  adjacent to the top surface  23  of the upper portion  20  of the housing  12 . A first of the seed guards  42  may be positioned towards a forward side of the housing  12  of the seed meter  10 , while a second of the seed guards  42  may be positioned towards a rearward side of the housing  12  of the seed meter  10 . 
     With reference to  FIG. 3 , each of the seed guards  42  may have a laterally-extending length that generally corresponds with the internal lateral width through the housing&#39;s  12  interior space. As such, each of the seed guards  42  can extend between the lateral side elements  26  of the upper portion  20  of the housing  12 . The seed guards  42  may be held in position, at least partly, via engagement between the interior sides of the lateral side elements  26  of the upper portion  20  of the housing  12 . Although the lateral side elements  26  can function to generally restrict lateral movement of the seed guards  42 , embodiments provide for the seed guards  42  to shift forward and rearward (between a normal operating configuration shown by the right seed guard  42  of  FIG. 12  and a retracted configuration shown by the left seed guard  42  of  FIG. 12 ) within the seed meter  10 . Such shifting provides for the seed guards  42  to selectively (1) prevent or restrict excess seed from flowing through the seed meter  10  and (2) enlarge the seed inlet  24  and/or the spacing between the seed guards  42  and the metering wheel  14  to permit passage of large obstacles through the seed meter  10 , as will be described in more detail below. Each of the seed guards  42  may be secured to the upper portion  20  of the housing  12  via one or more spring elements  48 , which are illustrated in  FIGS. 3 and 12 . A first of the seed guards  42  may be secured to a front side of the upper portion  20  of the housing  12  via a pair of a spring elements  48  that extend between the front side of the upper portion  20  and the base section  44  of the first seed guard  42 . Similarly, a second of the seed guards  42  may be secured to a rear side of the upper portion  20  of the housing  12  via a pair of a spring elements  48  that extend between the rear side of the upper portion  20  and the base section  44  of the second seed guard  42 . 
     In the normal operating configuration, as illustrated in  FIGS. 8 and 9 , at least a portion of the seed guards  42  extend underneath the seed inlet  24  so as to at least partially block the seed inlet  24 . For instance, in the normal operating configuration (as illustrated by the rearward seed guard  42  of  FIG. 12 ), a portion of the tip sections  46  of the seed guards  42  may extend underneath the seed inlet  24 . As such, the seed guards  42  function to restrict the opening presented by the seed inlet so as to direct seed to the metering wheel  14  by funneling the seed into the fluted sections  16 . In such an operating configuration, the seed guards  42  also prevent an overflow of seed from falling freely through the seed meter  10  (e.g., through the interior space presented between the metering wheel  14  and the housing  12 ). Instead, the seed guards  42  direct seed directly into the fluted section  16  of the metering wheel  14 , such that the metering wheel  14  can carry a precise volumetric amount of seed (as defined by the size of the fluted sections  16 ) around in an arcuate manner to be dropped out and exit the seed meter  10  via the seed outlet  28 . As such, the seed meter  10  of embodiments of the present invention is configured to meter specific and precise amounts of seed from the seed bin  32 , through the seed channel  43 , and onto and/or into the ground over which the seed planting machine  30  travels. 
     Some embodiments additionally provide, however, for the seed guards  42  to be shifted to a retracted configuration, as illustrated by the forward seed guard in  FIGS. 10 and 12 , in which the seed guards  42  are actuated against the force of their springs  48 . In such a retracted configuration, a portion of the seed guards  42  that extended underneath the seed inlet  24  in the normal operating configuration (e.g., including a portion of the tip sections  46  of the seed guards  42 ) may be shifted out from underneath the seed inlet  24  so as to clear the seed inlet  24  or to otherwise enlarge the effective flow-through area of the seed inlet  24 . Such retraction of the seed guards  42  also provides for an increase in spacing between the metering wheel  14  and the seed guards  42 . As such, with the seed guards  42  in the retracted configuration, large obstacles, including rocks and other debris, are permitted to pass from the seed bin  32  and through the seed meter  10  without damaging or jamming the seed meter  10 , as will be discussed in more detail below. 
     In some embodiments, to ensure sufficient securement of the seed guards  42  within the housing  12 , as well as to facilitate shifting of the seed guards  42  between the normal operating configuration and the retracted configuration, the lateral side elements  26  of the upper portion  20  of the housing  12  may each include linear groove elements  50 , as illustrated in  FIG. 3 , for engaging with the sides of the seed guards  42 . A pair of groove elements  50  on one lateral side element  26  is illustrated in  FIG. 3 . It is understood that the other lateral side element  26  also includes corresponding groove elements  50  on its interior side. In such embodiments, each of the seed guards  42  may also include linear protrusions or tabs  52  on each of its lateral sides, which are configured to fit within the groove elements  50 . With the linear protrusions or tabs  52  engaged within the groove elements  50 , the seed guards  42  can shift forward and rearward along the groove elements  50 . In certain embodiments, the groove elements  50  may be sized and positioned to ensure that the seed guards  42  at least partially block the seed inlet  24  when in the normal operating configuration. In addition, the length of the groove elements  50  may be sized so as to permit the seed guards  42  to shift away from the seed inlet  24  to the retracted configuration such that the seed guards are clear of the seed inlet  24  to permit large obstacles to pass. 
     The general operation of the seed meter  10  and its seed guards  42  will now be described in more detail. As was discussed previously,  FIG. 8  illustrates a seed meter  10  attached to a seed bin  32  and metering seed from the seed bin  32 . During such metering, the metering wheel  14  is shown rotating counter-clockwise. Nevertheless, it should be understood that the seed meter  10  can similarly meter seed with the metering wheel  14  rotating clockwise. As shown, the seed guards  42  are in their normal operating configuration, in which at least a portion of the seed guards  42  are positioned directly below a portion of the seed inlet  24 . In such a configuration, seeds are directed down through the seed inlet  24  and into the fluted sections  16  of the metering wheel  14 . Seeds are not, however, capable of freely flowing through the interior space of the housing  12  (e.g., between the metering wheel  14  and the housing  12 ) because the seed guards  42  direct the seed into the fluted sections  16  and prevent the seed from flowing past the metering wheel  14  without being received in one of the fluted sections  16 . With seed received in the fluted sections  16 , the metering wheel  14  will carry the seed (i.e., via rotation) past the seed guard  42  and the top surface  23  of the upper portion  20  of the housing  12 . After further rotation of the metering wheel  14 , the seed will be dropped out of the seed meter  10  via the seed outlet  28  down through the seed channel  43  and onto and/or into the ground. As such, the seed meter  10  is configured to meter specific and precise amounts of seed from the seed planting machine  30 . 
     Should the seed meter  10  encounter a large obstacle, such as the rock shown in  FIGS. 9-11 , embodiments of the present invention provide for the large obstacle to be passed through the seed meter  10  without causing damage to the seed meter  10  or interrupting operation of the seed meter  10  (e.g., jamming the seed meter  10 ). In more detail, as shown in  FIG. 10 , as the large obstacle drops down through the seed inlet  24 , the large obstacle will become engaged with the metering wheel  14  as the metering wheel  14  rotates. Beneficially, upon the large obstacle encountering the seed guard  42 , the large obstacle (under force from the metering wheel  14 ) will force the seed guard  42  to be shifted against the springs  48  to the retracted configuration. With the seed guard  42  in the retracted configuration, the large obstacle will be free to pass below the seed guard  42  and the top surface  23  of the upper portion  20  of the housing  12 . Continued rotation of the metering wheel  14  will assist the large obstacle to be carried around the interior space of the metering wheel  14 , such that the large obstacle will be dropped out of the seed meter  10  via the seed outlet  28 , as shown in  FIG. 11 . 
     As was described previously, the seed meter  10  of embodiments of the present invention is configured to operate with the metering wheel  14  rotating in either direction (e.g., clockwise or counter-clockwise). Beneficially, with the seed meter  10  including seed guards  42  on both its front side and its rear side, the seed guards  42  will permit both seed and large obstacles to pass through the seed meter  10  when the metering wheel  14  is rotating in either the clockwise or counter-clockwise direction. As such, the seed meter  10  is configured to meter specific and precise amounts of seed from the seed planting machine  30  regardless of the direction in which the metering wheel  14  is rotating. Furthermore, the seed meter  10  can permit large obstacles to pass without damaging or interrupting operation of the seed meter  10 , regardless of the direction in which the metering wheel  14  is rotating. 
     Operation of the seed meters  10  will now be described more broadly with respect to operation of a seed planting machine  30 , as illustrated in  FIGS. 4-6 . As previously described above, the seed planting machine  30  is generally configured to dispense seed onto and/or into the ground over which the seed planting machine  30  travels. Beneficially, because of the configuration of the seed meters  10  included within the seed planting machine  30 , the seed planting machine  30  can dispense seed onto and/or into the ground regardless of the direction in which the seed planting machine  30  is travelling. In addition, the seed planting machine  30  is capable of passing large obstacles that may be present within its seed bin  32  through the seed meters  10  without damaging or interrupting operation of the seed meters  10  regardless of the direction in which the seed planting machine  30  is travelling. 
     In more detail and with reference to  FIG. 4 , embodiments of the present invention include a seed planting machine  30  broadly comprising the seed bin  32  for housing seed, a ground-engaging roller mechanism  62 , a transmission assembly in the form of a rotation distribution assembly  64  for imparting rotation from the ground-engaging roller mechanism  62  to components of the seed planting machine  30 , such as to the seed meters  10 . The rotation distribution assembly  64  may include one or more axles, as well as a plurality of sprockets, pulleys, gears, or other rotational mechanisms linked by chains, belts, or the like. As such, the rotation distribution assembly  64  is capable of transmitting rotation from the ground-engaging mechanism  62  to a plurality of components of the seed planting machine  30 . 
     In certain embodiments, as shown in  FIG. 4 , the seed planting machine  30  will include only a single seed bin  32  for housing seed. However, the seed planting machine  30  may include more than one seed bin  32 . As illustrated by  FIGS. 5 and 6 , the seed bin  32  may be associated with one or more mixing/stirring components  70 , which may comprise gear-shaped mixing wheels, paddle wheels, auger agitators, mixing arms, or other similar mixing components. The mixing/stirring components  70  may be positioned along a generally elongated shaft  72 , which may form part of the rotation distribution assembly  64 . As such, rotation of the rotation distribution assembly  64 , and thus the elongated shaft  72 , will cause a corresponding rotation of the mixing/stirring components  70 . In operation, the mixing/stirring components  70  are operable to be rotated within the seed bin  32 , such that the mixing/stirring components  70  continually mixes the seed within the seed bin  32 , thereby keeping the seed from clumping together (i.e., coagulating), keeping the seed from bridging within the seed bin  32 , and generally keeping a consistent flow of seed to the seed meters  10 . 
     Embodiments of the present invention provide for one or more seed meters  10  to be secured to a bottom portion of the seed bin  32 . Specifically, as illustrated in  FIGS. 5 and 6 , the seed planting machine  30  may include a plurality of seed meters  10  spaced along the length of and secured to the bottom of the seed bin  32 . The seed meters  10  may be positioned along a generally elongated shaft  74 , which may form part of the rotation distribution assembly  64 . Specifically, the elongated shaft  74  may extend through each of the metering wheels  14  of the seed meters  10 . As such, rotation of the rotation distribution assembly  64 , and thus the elongated shaft  74 , will cause a corresponding rotation of the metering wheels  14  within the seed meters  10 . As perhaps best shown in  FIG. 6 , the metering wheels  14  may each be associated with one or more smooth-surfaced drums  75  and/or one or more locking elements  76  positioned on either side (or both sides) of the seed meters  10 . In some embodiments, each group of metering wheel  14 , drum  75 , and locking element  76  may be integrally formed together, such that the group of elements can rotate together. In more detail, the locking element  76  may include a set screw that engages with the elongated shaft  74 , such that the locking element  76 , as well as the integrated metering wheel  14  and drum  75 , can rotate in conjunction with the elongated shaft  74 . In addition, the locking element  76  can function to inhibit the metering wheel  14  and/or the drum  75  from shifting laterally along the elongated shaft  74 . With the set screw of the locking element  76  engaged with the elongated shaft  74 , a lateral shifting of the elongated shaft  74  can cause a corresponding lateral shifting of the metering wheel  14  and/or drum  75 . In addition, the seed meters  10  may be associated with a spacing element  78  positioned between certain of the seed meters  10  for inhibiting relative lateral shifting and maintaining spacing between metering wheels  14 . 
     In operation, the metering wheels  14  are operable to be rotated so as to capture seed falling into the housing  12  from the seed bin  32 . As the metering wheels  14  continue to rotate, the captured seeds are carried along until the seeds are dropped from the metering wheels  14  to fall out of the housing  12  and into the seed channel  43  to be planted or otherwise dispensed onto and/or into the ground. The rate at which seeds are dispensed is, at least partly, based on the speed at which the metering wheels  14  are rotated. In addition, and as will be discussed in more detail below, each of the metering wheels  14  may be laterally shifted, at least partially, to a position outside of the housing  12  so as to be capable of capturing fewer seeds from the seed bin  32 . As such, the rate at which seeds are dispensed from the seed meters  10  can be, at least partly, based on the lateral position of the metering wheels  14  with respect to their respective seed meter  10  housing  12 . 
     To provide rotational power to the seed meters  10 , embodiments of the present invention provide for the ground-engaging mechanism  62  to provide rotational power to the rotation distribution assembly  64 . The ground-engaging mechanism  62  may comprise various types of rolling mechanisms, such as a row of aerators, a row of disc harrows/tillers, an extended spiked roller, a packer roller, or the like. In other embodiments, the ground-engaging mechanism  62  may simply include one or more of the wheels of the seed planting machine  30 . In some embodiments, such as illustrated in  FIG. 4 , the ground-engaging mechanism  62  will be positioned at a rear of the seed planting machine  30 . In other embodiments, the ground-engaging mechanism  62  may be positioned at front, or at a position between the front and rear, of the seed planting machine  30 . Nevertheless, the ground-engaging mechanism  62  can be connected to the rotation distribution assembly  64  (e.g., via chains, belts, or the like), such that rotation of the ground-engaging mechanism  62  will cause a corresponding rotation of components of the rotation distribution assembly  64 . Further, rotation of the rotation distribution assembly  64  will cause a corresponding rotation of the metering wheels  14  within the seed meters  10  (e.g., via rotation of the elongated shaft  74 ). As such, the seed meters  10  are configured to dispense seed as the seed planting machine  30  travels over the ground. The rate at which seeds are dispensed from the seed planting machine  30  can be based on the speed at which the seed planting machine  30  is travelling over the ground. 
     In addition, the rate at which seed can be dispensed from the machine  30  can also be based on the extent to which each metering wheel  14  is positioned within the housings  12 . For example, if a metering wheel  14  is positioned entirely within the housing  12 , as illustrated in  FIG. 13A , the metering wheel  14  will be configured to fully accept seed from the seed been  32 . Specifically, with the metering wheel  14  completely positioned within the housing  12 , the entirety of the fluted sections  16  of the metering wheel  14  are available to capture seeds passing through the seed inlet  24  from the seed bin. In contrast, in some embodiments, the metering wheel  14  can be at least partially shifted outside of the housing  12 . For example, as illustrated in  FIG. 13B , the metering wheel  14  can be laterally shifted such that a first portion of the metering wheel  14  (e.g., approximately one-half of the metering wheel  14 ) is positioned outside of the housing  12 , while a second portion of the metering wheel  14  remains positioned within the housing  12 . As shown, a portion of the smooth-surfaced drum  75 , which is integrated with the metering wheel  14 , is laterally shifted along with the metering wheel  14  such that a portion of the drum  74  is positioned within the interior space of the housing  12 . 
     It should be understood that such a lateral shifting can be accomplished by laterally shifting the elongated shaft  74  to which the metering wheel  14  and/or the drum  75  is secured. In such a configuration (i.e., with only a portion of the metering wheel  14  positioned within the housing  12 ), only a portion of the fluted sections  16  are available to capture seed passing through the seed inlet  24  from the seed bin  32 . It is noted that the smooth outer surface of the drum  75  does not facilitate the capturing of seed. As such, the metering wheel  14  illustrated in  FIG. 13B  is configured to dispense seed at a slower rate than the metering wheel  14  illustrated in  FIG. 13A  (assuming an equivalent rotational speed). Finally, as illustrated in  FIG. 13C , the metering wheel  14  can be laterally shifted (i.e., via shifting of the elongated shaft  74 ) further, such that the metering wheel  14  is entirely outside of the housing  12 . The drum  75  is shifted along with the metering wheel  14 , such that the drum  75  is positioned completely inside of the housing  12 . In such a configuration, the seed meter  14  will not dispense seed, as there is no portion of metering wheel  14  fluted sections  16  available to capture seed. Instead, the smooth-surfaced drum  75  simply rotates within the housing  12 , not capturing seed from the seed bin  32  or dispensing seed from the seed meter  10 . 
     The embodiments shown in  FIGS. 13A-13C  provide an ability to control the rate at which seed is deposited from the seed planting machine  30 . With the metering wheels  14  positioned entirely within the housings  12  (i.e.,  FIG. 13A ), the seed meters  10  are configured to dispense a maximum amount of seed at any given rate of rotation of the metering wheels  14 . Laterally shifting the metering wheels  14  outside of the housings  12  provides for the dispensing rate to be reduced. The rate of dispensing seed can be reduced in a generally linear manner until the metering wheels  14  are positioned entirely outside of the housings  14 , at which time the seed planting machine  30  is stopped from planting seed. As such, the above-described embodiments are configured to act as a clutch for the seed planting machine  30 . For instance, as the seed planting machine  30  is travelling over the ground, the seed meters  14  can be at least partially positioned within the housings  12  (e.g.,  FIG. 13A or 13B ), such that the seed meters  10  can deposit seed onto and/or into the ground. Should the seed planting machine  30  encounter a section of the ground that does not require seed to be deposited, the metering wheels  14  can be laterally shifted, via lateral shifting of the elongated shaft  74 , to a position entirely outside of the housings  12  (i.e.,  FIG. 13C ), such that the seed meters  10  stop depositing seed. It is noted that with the metering wheels  14  positioned outside of the housings  12 , the seed meters  10  do not dispense seed even while the seed planting machine  30  continues to travel over the ground and the metering wheels  14  continue to rotate. 
     Beneficially, the seed meters  10  are configured to dispense seed regardless of the direction in which the seed planting machine  30  is travelling. As was described previously, the seed meters  10  are configured to dispense seed regardless of whether the metering wheels  14  rotated in a first direction (e.g., clockwise) or a second direction (e.g., counterclockwise). As such, with the seed planting machine  30  travelling in a first direction (e.g., forward), the seed meters  10  can dispense seed by having their metering wheels  14  rotate in a first direction (under power provided by the ground-engaging mechanism  62  and the rotation distribution assembly  64 ). Similarly, with the seed planting machine  30  travelling in a second direction (e.g., rearward or reverse), the seed meters  10  can also dispense seed by having their metering wheels  14  rotate in a second direction (under power provided by the ground-engaging mechanism  62  and the rotation distribution assembly  64 ). Thus, the seed meters  10  of embodiments of the present invention are configured to dispense seed regardless of the direction of travel of the seed planting machine  30 . 
     In view of the above, embodiments of the present invention include a method for planting seed with a seed planting machine  30 . The method can include a step of providing one or more seed meters  10  in association with a seed bin  32 . The seed meters  10  each include a housing  12  that presents a seed inlet  24  and a seed outlet  28 , and a metering wheel  14  positioned within the housing  12 . In some embodiments, each of the seed meters  10  may additionally comprise a pair of retractable seed guards  42  configured to be selectively configured in an operating configuration and in a retracted configuration. The method includes the additional step of travelling in a first direction with the seed planting machine  30 . During such travelling, the step further includes metering seed from the seed bin  32  via the metering wheel  14  rotating in a first direction. In additional embodiments, during such travelling step, the seed guards  42  may be configured in the operating configuration to prevent excess seed from passing through the seed meter  10 . The method includes a further step of travelling in a second direction with the seed planting machine  30 . During such travelling, the step further includes metering seed from the seed bin  32  via the metering wheel  14  rotating in a second direction. In some instances, a large obstacle may be present within the seed bin  32 . In such instances, embodiments provide that during such travelling step, at least one of the seed guards  42  may be configured in the retracted configuration to allow the large obstacle to pass through the seed meter  10 . 
     As such, embodiments provide for the metering of seed, in a precise and accurate manner, regardless of the direction in which the seed planting machine  30  is travelling. In addition, the seed meters  10  of embodiments of the present invention provide for large obstacles to pass through the seed meter  10  without damaging or interrupting operation of the seed meter  10 . 
     Although the invention has been described with reference to the one or more embodiments illustrated in the figures, it is understood that equivalents may be employed and substitutions made herein without departing from the scope of the invention as recited in the claims. 
     Having thus described one or more embodiments of the invention, what is claimed as new and desired to be protected by Letters Patent includes the following: