Abstract:
A nurse adapter mechanism for an agricultural seeding implement converts an air seeder meter box into a nurse inductor box to convey seed particles to the singulator of a planting mechanism. The nurse adapter mechanism is detachably mounted on the meter box of the air seeder to receive a supply of seed particles therefrom and utilizes the normal air flow for the metering mechanism to effect a nursing of seed particles to a planting mechanism. The nurse adapter mechanism diverts the stream of air into engagement with a pile of seed particles and induce the entrainment of the seed particles for conveyance thereof to the remote planting mechanism. A partition wall divides the nurse induction mechanism into a seed side and an air side. The seed side receives the supply of seed particles from the hopper and allows the seed to pass through a passageway into the air side for engagement by the stream of air. Divider walls are provided to isolate each discharge tube from the other discharges tube so that the planter mechanisms can provide a continuous supply of seed particles. The discharge tubes pass through the seed side of the nurse adapter mechanism in a stacked pair, modular configuration with the respective discharge tubes being adequately separated to permit the passage of seed particles therebetween.

Description:
This application claim benefit to provisional application 60/107,154 filing date Nov. 5, 1998. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates generally to air seeders for planting seeds in the ground in an agricultural environment and, more specifically, to a nurse inductor system co-operable with a planter mechanism to feed seed or other particulate material to a planting mechanism for insertion of that material into the ground. 
     As the size of agricultural implements continues to grow, the versatility of such implements becomes more significant. Large air seeders have become increasingly popular for the planting of seeds, fertilizer and other product without strict regard for the exact placement of the seeds particles. For crop planting operations that require seed singulation, nurse systems are used to feed seed or other particles from larger hoppers into smaller reservoirs located at the singulators. A nurse inductor system enables an air cart typically used for dryland farming, (cereal crops, etc.), to be adapted for use in row crop planting applications, such as corn and soybean, though not limited to soybean and corn. A nurse inductor system can be used to enable a farmer to singulate on-row, with one central hopper filling location, and to plant more acres before having to stop to fill the central hopper again, resulting in quicker planting and less labor, while maintaining the precision spacing available by on-row singulation. 
     In U.S. Pat. No. 5,161,473, a nurse system is disclosed which works off a specialized cart. The air comes into the seed delivery area coaxial with the seed tube that takes the air and seed to the row units. With this system substantial energy is used to nurse the seed since the air changes direction abruptly. This particular nurse system provides a dedicated fan to feed the 12 rows to be planted from the nurse system. This system requires the adding or removing of shims to adjust line length, which is difficult and inconvenient to accomplish. U.S. Pat. No. 5,156,102 and U.S. Pat. No. 4,060,181 teach other nurse embodiments. 
     It would be advantageous to provide an nurse inductor adapter that would be usable in conjunction with existing air carts to convert the existing metering mechanism to a nurse mechanism. 
     SUMMARY OF THE INVENTION 
     It is an object of this invention to provide a nurse inductor system operable for use with planters requiring singulation of the seeds for planting in the ground. 
     It is a feature of this invention that the nurse inductor system enables the use of an existing air cart for nursing seeds to individual planter units in a passive manner. 
     It is an advantage of this invention that the nursing system would not require the addition of active controls for the nurse induction mechanism, the system being self-regulating without any external electronic control systems being necessary. 
     It is another feature of this invention that replacement of existing components on a conventional air cart with nurse induction components, to convert the standard air cart without requiring permanent modifications to the cart. 
     It is another advantage of this invention that the induction of seed or other particulate product is accomplished more evenly and consistently, thereby reducing the possibility of a plugging of the lines. 
     It is yet another feature of this invention that bridging in the hopper side of the induction unit is avoided by increasing the room for particulate material to flow. 
     It is still another advantage of this invention that the air pressure and flow required by the nurse induction system is reduced, so that an existing fan on an air cart can be used for both nurse induction of seeds and the application of particles from one of more other air cart hopper(s) at the same time. 
     It is still another feature of this invention that the wings of the planter toolbar can be folded vertically without the need to empty particles out of the planter seed reservoir before folding. 
     It is yet another advantage of this invention that the planter toolbar can be folded with the wings pivoted closer to the first row unit on the wing section of the planter row unit without interference between the planter seed reservoirs. 
     It is yet another advantage of this invention that more than one planter singulator can be fed with one nurse inductor line, thus enabling the development of a wider planter toolbar with substantially more planter units than previously available. 
     It is a further advantage of this invention that the nurse inductor mechanism can be used on an air cart that may also be used in dryland farming. 
     It is still another object of this invention to provide an adapter mechanism that can be mounted on a conventional air cart in place of a conventional meter mechanism to convert the air cart into a nurse inductor apparatus. 
     It is yet another feature of this invention that the adapter mechanism utilizes the conventional air source from the air cart without requiring a separate air flow mechanism. 
     It is still a further advantage of this invention that the nurse adapter mechanism can be installed on a conventional air cart hopper without requiring the entire meter box to be removed from the hopper. 
     It is yet a further advantage of this invention that the use of a common air source enables the air cart to both nurse seed particles and meter fertilizer to a planting mechanism simultaneously. 
     It is still a further object of this invention to provide nurse adapter mechanism for an agricultural seeding implement which is durable in construction, inexpensive of manufacture, carefree of maintenance, facile in assemblage, and simple and effective in use. 
     These and other objects, features and advantages can be accomplished according to the instant invention by a nurse adapter mechanism for an agricultural seeding implement in which the nurse adapter mechanism converts an air seeder meter box into a nurse inductor box to convey seed particles to the singulator of a planting mechanism. The nurse adapter mechanism is detachably mounted on the meter box of the air seeder to receive a supply of seed particles therefrom and utilizes the normal air flow for the metering mechanism to effect a nursing of seed particles to a planting mechanism. The nurse adapter mechanism diverts the stream of air into engagement with a pile of seed particles and induce the entrainment of the seed particles for conveyance thereof to the remote planting mechanism. A partition wall divides the nurse induction mechanism into a seed side and an air side. The seed side receives the supply of seed particles from the hopper and allows the seed to pass through a passageway into the air side for engagement by the stream of air. Divider walls are provided to isolate each discharge tube from the other discharges tube so that the planter mechanisms can provide a continuous supply of seed particles. The discharge tubes pass through the seed side of the nurse adapter mechanism in a stacked pair, modular configuration with the respective discharge tubes being adequately separated to permit the passage of seed particles therebetween. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The advantages of this invention will be apparent upon consideration of the following detailed disclosure of the invention, especially when taken in conjunction with the accompanying drawings wherein: 
     FIG. 1 is a side elevational view of a typical air seeder mechanism on which a nurse induction mechanism incorporating the principles of the instant invention is mounted; 
     FIG. 2 is a schematic cross-sectional view of the nurse induction system depicted in FIG. 1, the arrows depicting the direction of air flow through the mechanism; 
     FIG. 3 is an enlarged schematic cross-sectional view of the nurse induction mechanism shown in FIG. 2 to depict the flow of air and seed through the uppermost seed distribution tubes leading to the planting mechanism, the arrows depicting the direction of air flow through the mechanism; 
     FIG. 4 is an enlarged schematic cross-sectional view similar to that of FIG. 3 except depicting the flow of air and seed through the lowermost seed distribution tubes to the corresponding planting mechanism, the arrows depicting the direction of air flow through the mechanism; 
     FIG. 5 is a perspective view of the divider wall portion of the nurse induction apparatus to depict the divider walls separating the uppermost and lowermost seed distribution tubes; 
     FIG. 6 is a perspective view of the particle hopper side of the nurse induction unit, with the exterior induction box wall removed, the nurse distribution lines being oriented in vertical pairs to leave open space between the lines for the particles to pass through; 
     FIG. 7 is a perspective view of the outlet side of the nurse induction unit seen from the exterior of the apparatus; 
     FIG. 8 is a front elevational view of a typical planting mechanism adapted for operative association with the nurse system depicted in FIG.  1  and incorporating the principles of the instant receiver header invention, the side wings of the planting mechanism being folded upwardly relative to the central section to place the planting mechanism in a transport position; 
     FIG. 9 is a front elevational view of the planting mechanism depicted in FIG. 8 except with the side wing sections being folded down into an operative position; 
     FIG. 10 is an enlarged elevational view of the nurse system receiver apparatus corresponding to the circled mechanism within FIG. 9; 
     FIG. 11 is an enlarged perspective view of the nurse system receiver assembly; 
     FIG. 12 is an enlarged front elevational view of the nurse system receiver assembly shown in FIG. 11; 
     FIG. 13 is an enlarged side elevational view of the nurse system receiver assembly shown in FIG. 12; 
     FIG. 14 is a perspective view of the nurse system receiver header assembly; 
     FIG. 15 is a side elevational view of the nurse system receiver header assembly shown in FIG. 14; 
     FIG. 16 is a front elevational view of the nurse system receiver header assembly shown in FIG. 14; 
     FIG. 17 is a top plan view of the nurse system receiver header assembly shown in FIG. 14; and 
     FIGS. 18 a-d  are perspective, side and front elevational, and top plan views of the nurse system receiver header assembly vent. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring first to FIGS. 1-4, the principles of the nurse induction apparatus can best be seen. The nurse induction adapter is mounted on a conventional air seeder, air cart, and redirects the air stream  13  coming from the fan  11  in an air cart box  10  into a path that leads through the nurse inductor  20 . The air stream is guided into a nozzle region  30  that directs the air along a flow path that tangentially engages a pile of seed particles S exiting the opening  19  at the bottom of the seed hopper  12 . The turbulence of the blast of air from the nozzle  30  loosens the seed particles from this assemblage of seed particles S exiting the opening  19  in the bottom of the seed hopper  12 , entraining the individual seed particles into the air stream as it follows a path to the distribution lines  22  above the seed particle pile. The individual seed particles remain suspended in the air stream where the air bleeds off and the individual seed particles fall by gravity into a second pile or mass at the planting mechanism. 
     As best seen in FIGS. 3-7, the air stream  13  through the nurse inductor apparatus  20  is split at the general location of the seed particle mass at the bottom of the central seed hopper  12  on the air cart  10  into individual sections  31  that are isolated by generally vertical walls  32 . Each individual section  31  leads to a different seed distribution tube  22  and, ultimately, to a different receiver header  45  and associated receivers  40 . The nurse inductor  20  induces seed particles into the air stream when and where there is demand for the particles. The demand for particles is controlled by the level of product in each respective receiver on the output end of the seed distribution tube. When the receiver  40  is full, air is restricted from escaping from the seed distribution tube by the massed seed particles within the seed distribution tube. As a result of the filled receiver  40 , which prevents the passage of air there through, the air flow and air velocity reduce due to increased pressurization of the line. This resultant reduction in potential air pressure reduces the capacity of the flow of air to induce the seed particles into the corresponding seed distribution tube  22 . Since the flow of air through the nurse inductor  20  is spread across the entire unit, the flow of air will tend to go to the lines that have open receivers because of the less airflow resistance. 
     The divider walls  32 , that separate the air and entrained seed particles flows to each respective seed distribution tube  22 , are sealed such that air cannot get into the seed distribution tubes  22  downstream of the pickup area. The sealed vertical walls  32  also prevent cross over of air and entrained seed to different seed distribution tubes  22 . This division of airflow enhances operation since each line is operable to run at different times, depending on demand as represented by the massed seed particles in the output end of the seed distribution tubes  22 . 
     The shape of the air and entrained seed particle flow path has an impact on the performance of the inductor. When the receiver  40  is filled to allow only a small volume of air to flow through the receiver, air alone is still capable of traveling through the lines, through the massed seed particles and past the seed particles at the vent. If seed particles were to be allowed to be induced into the lines with airflows that are less than carrying velocity, a blocking of the seed distribution tubes  22  can occur. This problem of blocking the seed distribution tube  22  can be avoided by forming the portion of the inductor structure, just above the area adjacent to the bottom of the central seed hopper where the individual seed particles are entrained into the airflow, larger so that the air velocity slows down in this region. 
     With the slowed air velocity, any seed particles that had been entrained into the slow flowing air stream fall out of the airflow and are dropped back into the seed particle mass region. Thus, the seed particles are picked up and carried by the air stream only when the air velocity is above the minimum carry velocity, thereby allowing air to be flowing slowly without transporting any entrained seed particles into the full seed distribution tube. Correspondingly, the cross-sectional area of the seed distribution tubes is smaller than the cross-sectional area between the generally vertical walls dividing the plenum into discreet channels. As a result, the air velocity increases once entering the seed distribution tube, allowing the seed particle to be retained within the air stream once it enters the seed tube. 
     The regulator  25  for the flow of seed particles into the area for entrainment within the air stream is defined by a movable gate  29  forming a common edge along which seed particles flow into the particle pick-up area. The product regulator  25  extends across the entire nurse induction apparatus  20 . As the seed particles flow under the product regulator, the seed particles form a pile falling naturally at the angle of repose of the seed particles. The angled surface of the pile of seed particles forms the bottom wall of the air channel in the pick-up area. The proximity of the air nozzle  30  to the wall of product affects the amount of product carried in the air stream. As the regulator  25  is rotated and more or less product is permitted to pass through the opening  19   a  at the bottom of the central seed hopper  12 , the seed particles fall either closer to or farther from the air nozzle  30 . Since different products, such as different seed types, have properties that affect how easily the air stream picks them up, as well as the differences in the angle of repose at which the products slump, the ideal distance between the product surface and the air nozzle varies with the product being distributed. The product regulator  25  is adjustable to enable the optimum distance to be set for each product type, as well as the desired flow rate. 
     As the air stream  13  strips the product away close to the bottom of the product regulator  25 , product from the hopper  12  replenishes the created cavity. The closer to the bottom of the regulator  25  the product is stripped away, the more quickly the product is replenished. Thus, when the regulator  25  is positioned correctly for the specific type of product being nursed, the induction of product into the air stream is relatively steady. During testing, it was found that steady induction of product into the air stream reduced plugging problems within the distribution tubes  22  while maximizing product delivery efficiency. 
     The product regulator  25  is located on the hopper side of the induction box so that it does not interfere with the seal of the divider walls  32 . The product regulator  25  is formed as a single crescent shaped plate  29  that extends across the entire width of the induction unit  20 . The regulator plate  29  is attached to a shaft that is rotated by an external handle  28 . Thus, the flow of product across the induction box is controlled with the adjustment of a single handle  28 . As a result, the flow rate of seed particles can be controlled for all of the tubes  22  simultaneously, and can be completely shut-off to permit clean-out during which process the air will still be guided through the distribution tubes  22  without carrying seed particles. The rotatable regulator plate  19  can be adapted easily for remote control by appropriate actuators connected to the regulator  25 . Such a configuration is particularly advantageous in precision farming practices, as the flow of seed particles through the seed distribution tubes  22  can be turned on and off easily. Alternatively, the regulator  25  could be configured to control the flow of air through the nozzle  30  instead of the flow of seeds. 
     The generally vertical divider walls  32  are constructed such that the nurse inductor apparatus is made in pair segments that are stacked to fit the width of the induction box. The vertical nature of this modular design allows the inductor apparatus to be compact. The modularity of such a design allows the nurse inductor to be easily adapted to different widths and numbers of product lines, including a compact induction box width having a large number of product lines. To allow more space on the particle hopper side of the inductor unit, the distribution tubes  22  forming the outlet pipes are stacked in vertical pairs. The additional space between outlet pipes reduces bridging of the particles as they flow past the pipes and into the region of the product regulator  25 . Each distribution tube  22  is independent. The walls  32  dividing the distribution tubes are curved to direct the air and entrained seed particle stream as shown in FIG.  5 . The air and entrained seed make relatively small directional changes in the inductor apparatus, which improves the efficiency of the air system. This efficiency enables both the nursing of more than 12 rows and the use of the second air cart tank for simultaneous fertilizer operations. 
     Alternatively, the nurse induction unit  20  is adaptable for use with a stand-alone tank, as well as for with an air cart. Furthermore, the nurse induction unit  20  can also be adaptable to other planter units. As best seen in FIGS. 1 and 2, the nurse induction apparatus is preferably formed as a modular unit that can be inserted into a standard air cart structure to convert the air cart from a straight meter box into a nurse induction box. The conventional air delivery tubes  17  are sealed and remain on the air cart  10 , while the nurse induction unit  20  is interposed to receive the air stream  13  from the fan  11 . A connection mechanism  16  facilitates the convenient connection of the nurse unit  20  to the air cart  10  as a modular component. 
     One skilled in the art will recognize that the instant invention is not limited to the conveyance of seed particles, as other particulate matter is commonly distributed through an air cart system, such as fertilizer. Furthermore, the typical air cart  10  is provided with multiple hoppers or tanks containing different product to be planted in the ground. One tank could have seed stored therein, while another tank would have fertilizer and yet another tank could have herbicides or still another reservoir of fertilizer. In such multi-tank configurations, one of the tanks could be provided with a nurse induction unit  20  to convey seeds to the planting devices, while a conventional meter box is used to control the flow of fertilizer or other product to the planting devices by separate distribution tubes. Such a conventional meter box could apply the fertilizer or other product at a variable rate and could be controlled by an electronic controller, as is known for precision farming techniques. Other alternative configurations can include one tank nursing seed to all the singulators, as well as multiple tanks nursing seeds to any one particular singulator. 
     Referring now to FIGS. 8-18 d , the nurse system receiver  40  and receiver header  45  can best be seen. The receiver  40  and receiver header  45  are used in conjunction with the nurse inductor system  20 , such as the one described above. One skilled in the art will recognize that the header  45  is needed in configurations where the flow is to be split between multiple receivers. The nurse inductor  20  sends an air and entrained particle stream to the receiver  40  when the receiver has less than a desired level of product particles in it. The receiver header  45  is designed to allow air from the air and entrained product particle stream to escape when the particle level is below the air vent, but to limit the amount of air to escape when the particle level is above the air vent  50 . 
     The receiver  40 , as shown in FIGS. 11-13, provides a small mass of seeds in the location of the singulator pickup area  41 . The seeds S are massed in the receiver  40  and in the line  42  from the receiver  40  up to the receiver header  45 , which is the start of the leg  46  in the header Y. When the seeds are accumulated up to the top of the leg  46 , they block the flow of air through the air vent  50  near the header bottom. When the air does not flow freely through the air vent  50 , the flow of particles from the nurse inductor unit diminishes as described above. Only the small flow of air that can escape through the particles and vent  50  will continue to flow. This airflow is too low to entrain or pick-up particles. 
     If only one leg  46  of the Y is full, particles will continue to be nursed into the empty leg  47  until the air vent  50  is covered in the second leg  47  also. Then, the airflow to the header  45  will drop off and particles will not be sent in the nurse line  22  until such a time that one of the receivers  40  is emptied below the level where its air vent  50  is free. The nurse line  22  leading to the receiver header  45  is smaller than the lines  42  between the header  45  and the receiver  40  to reduce the velocity of the air flow at the receiver header  45 , thus allowing the entrained seed particle to drop out of the air stream and fall be gravity to the receiver  40 . To stop blocking of particles in the nurse line  22 , the receiver header  45  is mounted such that the inlet line  48  is always vertically above the outlet lines  42 , regardless of the implement position. As best seen in FIGS. 8-10, the header  45  is mounted such that it sits at an angle inclined to the vertical in operating position. The mounting of the header  45  also permits the header  45  to be moved through vertical to an opposite angle to the vertical in the transport position, which typically involves the rotation of the header through an angle in the range of 70 to 110 degrees, or approximately 90 degrees. The header  45  never inverts to allow particles to flow out of it back down the nurse line  22  which would cause plugging. The header mount design enables folding of the planter P into transport with fill receivers  40 . The header  45  never inverts, so the seed particles S stay in the receivers  40  when the planter P is moved between transport and operative positions. 
     The vent hood  52  makes a roof over the vent  50  to allow the air to be vented out and guard against rain and contaminants getting in. The orientation of the receiver header  45  always keeps the hood  52  opening facing down, even when the toolbar is rotated into transport. Other embodiments may use receiver headers  45  that are single or triple, or other variations. It is also possible that the vent and rain guard may be incorporated directly into the receiver design if a separate header is not desirable. The single design would be mounted at an angle to provide a similar function to trap seed particles when moving into and out of transport. The single design would also preferably incorporate the vent and rain hood in a manner similar to the double configuration described above. Since the single configuration would feed only a single receiver, it would be desirable to mount the header directly onto the receiver or to incorporate the header into the receiver design. The triple configuration would be similar to the double configuration described above with the addition of one single leg. 
     The nurse inductor  20  enables the use of a standard air cart  10  for both the central hopper and the nurse system air source. The air cart fan can be used for both fertilizing and nursing operations simultaneously. The inductor  20  can be designed in an adapter arrangement, which enables the air cart  10  to be readily converted from a roller type metering system to the nurse inductor system, and vice versa. The change to the cart to enable nurse induction is not permanent and does not require the use of time-consuming threaded fasteners. 
     It will be understood that changes in the details, materials, steps and arrangements of parts which have been described and illustrated to explain the nature of the invention will occur to and may be made by those skilled in the art upon a reading of this disclosure within the principles and scope of the invention. The foregoing description illustrates the preferred embodiment of the invention; however, concepts, as based upon the description, may be employed in other embodiments without departing from the scope of the invention.