Abstract:
A commodity tank for use with an air seeding implement includes a series of panels arranged to form an enclosure defining a volume configured to hold a supply of commodity. At least one or more of the panels has a warping-reducing bend formed therein. The commodity tank further has a series of tubular members with each tubular member located between adjacent and perpendicular panels to define a respective corner of the enclosure.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a divisional of application Ser. No. 13/167,378 filed Jun. 23, 2011. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates generally to farm implements and, more particularly, to a commodity tank for an air seeder. 
     An air seeder is an agricultural implement that is commonly used to plant usually a seed crop in a large field. Air seeders typically have centrally located hoppers for seed and fertilizer which distributes them through an air stream to individual seed rows. It is convenient to fill, easy to clean out and move. Any crop that can be grown from seeds—which might vary is size from oilseeds to corn, can be sewn by an air seeder. 
     The seed and fertilizer hoppers are usually carried on a large cart located behind or in front of the seeder. The air stream is created by a high capacity fan mounted on the cart which blows air through conduits (pipes) connecting the hoppers and the row units. Seed and fertilizer are metered out from the hoppers by a meter wheel that is turning in a ratio set by the operator for the proper seed rate or seed density. The seeds enter the pipe in the airstream and follow the pipes which terminate in the seedbed. Openers pulled through the soil make the opening where the seeds are placed. They are typically made of steel in the shape of points, discs or cultivator shovels. Once placed in the seed bed, the air is blown out the opening in the soil and the seed and fertilizer remain. The seeder can then pack the soil tight to retain moisture near the seed and harrow the furrows so the field is not rough. 
     A typical air seeder has an agricultural commodity cart (“air cart”) comprising at least one, and commonly two, three or more tanks for carrying various agricultural products like seed and fertilizer, which are bolted or otherwise attached to the frame of the commodity cart. The tanks are typically made from either polyethylene, such as found on a CaseIHPrecision Air 3380, or steel such as found on the CaseIH Precision Air 3580. 
     There is a continued demand for larger capacity commodity tanks. Larger tanks are particularly desirable for wider seeding implements, such as the CaseIH Precision Air 3580. Wider seeding implements are capable of depositing more seed in a single pass. Wider seeding implements will consume seed more rapidly than smaller implements. Hence, there is a general desire to outfit wider seeding implements with larger capacity commodity tanks. 
     Larger capacity commodity tanks are typically assembled from planar sheet panels. The corners of the tanks are typically formed by separate corner pieces that are attached to a pair of sheet panels. Alternately, it is also common for the ends of adjacent panels to be bent to form an overlapping joint. Regardless of how the corners are made, as the commodity tanks are made larger, the sheet metal panels that collectively form the tanks are consequently larger, One of the drawbacks of larger sheet metal panels is the increased tendency for such panels to warp due to manufacturing processes such as welding or media blasting. One approach to reduce this warping has involved the intentional formation of a bend along the width of the sheet metal panel. Unfortunately, these bends make the connections to mating panels more difficult because basic shapes such as a single overlapping bend or a single bend corner cap cannot be used. 
     SUMMARY OF THE INVENTION 
     The present invention provides a method and apparatus for effectively fabricating larger commodity tanks that are formed from a series of sheet metal panels having a warp-reducing bend. To make the interface between panels with warp-reducing bends and planar mating panels at the corners of the commodity tank more effective, the present invention provides a commodity tank having square tubes at the corners. 
     The square tubes provide a large flat surface for the bent sheet panel to mate to as well as an expansive perpendicular surface to which the adjacent mating panel can be attached. Placing the tubes in the corners of the commodity tank also allows the square tubes to be used as structural members for interfacing with the frame of the air seeder. Additionally, the square tubes may be made hollow and used as ducting to introduce pressure from the air system of the air seeder into the commodity tank. 
     Therefore, in accordance with one aspect of the invention, a commodity tank for use with an air seeding implement includes a series of panels arranged to form an enclosure defining a volume configured to hold a supply of commodity. At least one or more of the panels has a warping-reducing bend formed therein. The commodity tank further has a series of tubular members with each tubular member located between adjacent and perpendicular panels to define a respective corner of the enclosure. In one embodiment, the tubular members are elongated square tubes. 
     In accordance with another aspect of the invention, a commodity tank for use with an air seeder includes a series of generally rectangular shaped panels of sheet metal interconnected by an equal number of corner members otherwise separate from the panels. The corner members are each comprised of an elongated square structural member. 
     The invention may also be embodied in a method. Accordingly, the present invention provides a method of manufacturing a tank for use with an air seeder. The tank includes a plurality of generally planar panels forming sides of the tank. The method includes attaching adjacent planar panels to an elongated corner piece having a generally square-shaped cross-section. The panels and the elongated corn eves collectively define an enclosure for holding a granular commodity. 
     Various other features, objects and advantages of the present invention will be made apparent from the following detailed description and the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings illustrate one preferred embodiment presently contemplated for carrying out the invention. 
       In the Drawings: 
         FIG. 1  is an isometric view of an air cart having a commodity tank according to one embodiment of the invention; 
         FIG. 2  is a top isometric view of a commodity tank according to one embodiment of the invention; 
         FIG. 3  is a section view of the commodity tank taken along line  3 - 3  of  FIG. 1 ; 
         FIG. 4  is a section view of the commodity tank taken along line  4 - 4  of  FIG. 1 ; 
         FIG. 5  is a partial cutaway end view of the commodity tank; 
         FIG. 6  is an enlarged isometric view of a divider plate and sidewall of the commodity tank connected to a connecting member according to one embodiment of the invention; 
         FIG. 7  is an isometric view of a sidewall of the commodity tank connected to a corner member according to one embodiment of the invention; 
         FIG. 8  is a rear isometric view of a end plate of the commodity tank connected to the corner member according to one embodiment of the invention; 
         FIG. 9  is an end view of a sidewall of the commodity tank; 
         FIG. 10  is an enlarged view of the sidewall of  FIG. 9  shown connected to a corner member of the commodity tank according to an embodiment of the invention; 
         FIG. 11  shows a corner member according to another embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     Turning now to  FIGS. 1-4 , an air cart  10  having a pair of commodity tanks  12 ,  14  mounted to a frame  16  is shown. The frame  16  is of generally conventional design and thus will not be described further herein. Additionally, it is understood that the commodity tank  12  could be mounted to different types of frames. The illustrated commodity tanks  12 ,  14  have two hatches  18 ,  20  and  22 ,  24 , respectively. Hatches  18 ,  20  open into a shared compartment  26  and hatches  22 ,  24  open into separate compartments  28 ,  30 , respectively. As best shown in  FIGS. 3 and 4 , compartments  28 ,  30  are separated from one another by a divider plate  32 , which is also shown in phantom in  FIG. 1 . It is contemplated that the divider plate  32  may be a fixed mounting within tank  14  or may also be removably mounted. As also shown in  FIG. 4 , each compartment has respective lower portions  34 ,  36 ,  38  that are flow coupled in a known manner to a commodity delivery system (not shown). 
     It is understood that the invention is not limited to a commodity tank having two separate compartments. Moreover, while the air cart  10  is shown having a pair of commodity tanks, it is understood that the invention is not so limited. Thus, in one embodiment of the invention, an air cart may be equipped with a single tank or could have more than two such tanks “stacked” on a frame to tailor an air cart for a specific sized implement or satisfy a particular consumer request. 
     For purposes of further describing the invention, commodity tank  14  will be described more fully below but it is understood that commodity tank  12  is similarly constructed. Moreover, as shown in  FIG. 1 , multiple tanks can be mounted on a shared frame  16  to form an air cart  10  capable of holding larger volumes of grain, seed, granular chemicals, and the like. 
     Turning now to  FIG. 2 , commodity tank  14  generally consists of an upper portion  40  and the aforementioned lower portions  36 ,  38 . In most simple terms, the upper portion  40  defines the upper region of compartments  28 ,  30  to each have generally rectangular volumes whereas the lower portions  36 ,  38  are shaped so that the lower region of the compartments  28 ,  30  each have generally frustoconical volumes. 
     The upper portion  40  is defined by a series of panels connected to one another using conventional assembling processes, such as welding. More particularly, the panels include upper end panels  42 ,  44  (shown in  FIG. 4 ) and upper side panels  46 ,  48 , The upper end and upper side panels are connected to top panel  50  in which the hatches  22 ,  24  are formed. 
     The panels further include end wall  52  and sidewalls  54 ,  56 . End panel  42  is positioned opposite end wall  52 , as shown in  FIG. 4 , and effectively functions as another end wall for commodity tank  14 . The sidewalls  54 ,  56  connect to the end panel  42  and end wall  52  via corner members  58 ,  60 ,  62 ,  64 . The interconnection with the corner members will be described more fully below. in a preferred embodiment, the panels are formed from sheet metal. 
     As shown in  FIGS. 5, 6, 7, and 9 , the sidewalls  54 ,  56  are bent to reduce warping. Sidewall  56  will be described but it is understood that sidewall  54  is similarly designed. Sidewall  56  generally consists of a panel of sheet metal that is bent in a conventional manner to form an inwardly extending bent portion  66  generally defined at the midpoint in the height of the panel. In this regard, the bent portion  66  segments the panel into an upper panel portion  68  and a lower panel portion  70 . In a preferred embodiment, the bent portion  66  extends along the entire width of the sidewall  56 . The sidewall  56  has upper edge  72  that abuts against upper side panel  48  and a lower edge  74  that fits over a top edge of a corresponding panel (not numbered) of the lower portion  38 . it is understood that the top and bottom edges of the sidewall  56  could be weld to the upper side panel  48  and the lower portion  38 , respectively. 
     With particular reference to  FIG. 7 , the sidewall  56  has first and second side (lateral) edges  76 ,  78  that are connected, i.e., weld, to respective corner members  60 ,  62 . As best shown in  FIG. 5 , corner members  58 ,  60  are elongated square tubes that extend along the entire height of the sidewalls  54 ,  56  and, as such, upright along their entire length. In contrast, corner members  62 ,  64  have an upright portion  80  and an inclined portion  82 . Corner members  62 ,  64  are also square shaped but have a slightly different orientation than corner members  58 ,  60  to match the cut of the sidewalls  54 ,  56 . 
     It will be appreciated that the square-shaped profile of the corner members provides relatively wide, planar surfaces to mate with the sidewalls  54 ,  56 , the upper end panel  44 , and end wall  52 . Thus, rather than forming corners with a complimentary bent portion to match the bent portion of the sidewalk, the present invention provides a commodity tank having square tubular corner members that present a flat surface to which the bent portions can be connected in a conventional manner, such as welding. 
     Additionally, and as best shown in  FIGS. 1, 5 and 8 , the configuration of the corner members  58 ,  60 ,  62 , and  64  provide planar lower surfaces that mate with frame brackets  84 ,  86 ,  88 ,  90 ,  92 ,  94  for coupling the commodity tank to the frame  16 . In a preferred embodiment, frame brackets  86 ,  92  are sized to mate with two corner members, i.e., the adjacent corner members of tanks  12 ,  14  as shown in  FIG. 1 . 
       FIG. 10  shows the mating of sidewall  56  with corner member  62  according to the present invention. It can be seen in the figure that the planar face  96  provides a wide seat for the lateral edge  98  of the bent portion  66 . The increased surface area of the planar face  96  enables the sidewall  56  to be weld to the corner member  62 . Similarly, the side face  100 , which is oriented ninety degrees from planar face  96 , provides a wide surface area for welding, or otherwise connecting, the upper end panel  44  to the corner member  62 . It will be appreciated that the other faces (not numbered) of the corner member  62  provide a similar benefit. 
     From the foregoing it will be appreciated that the present invention provides a commodity tank design having corner members with relatively large, flat surfaces for the bent sheet metal (sidewalk) to mate to while also providing relatively large, flat surfaces at perpendicular angles for the other walls or panels of the tank with which to mate. Additionally, by using the square tubes as corner members for the commodity tank, the square tubes can attached to mounting brackets for securing the tank to the frame. Further, it is contemplated that square tubes, which are preferably hollow, can be flow-coupled to the air system of the air seeder and used for ducting air from the air system into the tanks. Thus, for example, it is contemplated that vent holes  102 , as shown in  FIG. 11 , may be formed in one or more of the interior surfaces of the corner members so that air may be ducted into the tank. In the illustrated example, each corner member has four (4) vent holes spaced at equal intervals along the length of the corner member. However, it is understood that more than four or less than four vent holes could be used. Similarly, it is contemplated that the position of the vent holes could be different from that shown. For example, the vent hole(s) could be placed near the upper end of the corner members. 
     It is further contemplated that the air flow through each vent hole could be the same or different. For example, it is contemplated that the size of the orifices forming the vent holes could vary within a single corner member to differentiate the velocity of air flow. It is also contemplated that conduits (not shown) could be run through the corner members and flow-couple with respective vents to provide dedicate air streams with potentially differing velocities to the several vent holes. 
     It is also contemplated that the orifices forming the vent holes could be formed to provide directional airflow. For example, the orifices could be shaped such that the air flow exits the orifices in along an upward or downward trajectory. It is further contemplated that the vent holes may be have corresponding covers that are mechanically linked, for example, to a control device that allows a user to open, partially close, or close a selected vent holes. Preferably, such control devices are accessible from outside the commodity tank and allow the vent holes to be open or closed even with a commodity is contained within the tank. 
     It is further contemplated that the airflow through one or more the vent holes could be sensed and used to provide manual or automated control of any fans, blowers, pumps, motors, and the like that drive air to the corner members through the vent holes. It is further contemplated that the vent holes may include screens to prevent the passage of commodity therethrough. 
     Alternatively, one or more of the corner tubes may have an open bottom flow-coupled to the air source and a (at least partially) open top that is open to the interior volume of commodity tank. 
     The present invention has been described in terms of the preferred embodiment, and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims.