Abstract:
A pneumatic delivery system for particulate agricultural products includes one or more compartment for containing and supplying one or more particulate product. An inductor assembly separately receives and fluidizes the particulate products and conveys the fluidized products to a metering assembly. The metering assembly separately meters each of the product flows and transfers the metered flows to one or more delivery units for applying the products. The pneumatic delivery system can be used on various implements, including planters and applicators for applying seeds, fertilizer, pesticides and other products.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to agricultural equipment, and, more particularly, to a pneumatic agricultural product delivery system on an application implement, such as a planter or fertilizer application equipment, for applying particulate material such as seed, fertilizer, herbicide or insecticide in a field, either as a surface application or deposited in the soil. 
     2. Description of the Related Art 
     Pneumatic agricultural product delivery systems are known to utilize a flow of air to assist in the delivery and movement of particulate material or product such as fertilizer, seed, insecticide or herbicide from a product supply chamber through an interior passage provided by a series of elongate tubes which extend from the product supply chamber to a product applicator that places the product on or in growing medium, such as soil. Such pneumatic agricultural product delivery systems are commonly employed in planters, air drills, fertilizer and pesticide applicators and a variety of other agricultural implements. 
     Agricultural implements that employ a pneumatic agricultural product delivery system are known to have a particulate material supply source such as one or more tanks that are loaded with the particulate material or materials to be applied. The tanks have or are associated with a metering device, which typically consists of a rotating element, which meters the particulate materials from the tanks into a set of distribution channels, such as conduits, hoses, etc., for application to the farm field. In most systems, a pneumatic source such as a fan or blower provides air to convey and distribute material through the distribution channels. Once the metering of particulates is done and the mix of air and particulates is in the distribution channels, the solid concentration should remain nearly constant and in dilute phase. 
     Systems as described have provided certain advantages and have worked acceptably in some aspects, but are not without disadvantages, inefficiencies or inconveniences. For example, the long distribution lines following the metering device can plug and interrupt the flow of material to the units that apply the material to the field. Further, it is desirable to use a material supply source, such as a tank, with different applicator equipment by, for example, coupling the tanks with a planter for planting seed, and later coupling the same tank equipment with an applicator for applying needed pesticides and/or fertilizer. This has been difficult due to the necessary metering systems for applying the different materials. With the metering device provided on the tank, it is necessary to adjust the metering device whenever the tank is used for supplying a different material. This can be time consuming and inconvenient if the metering device is underneath the tank. Moreover, tank pressurization can be complex using metering devices due to the differences in pressure between the tank and meters. 
     What is needed in the art is an agricultural product conveying system which improves efficiency and convenience. 
     SUMMARY OF THE INVENTION 
     The present invention provides an agricultural product air conveyor system which transfers particulate material from a source container to application equipment on demand, and meters the material at the application equipment. 
     The invention in one form thereof is directed to a pneumatic agricultural product delivery system including at least one particulate material supply compartment; at least one particle delivery unit for applying particulate material from the supply compartment; a metering assembly providing a metered flow of particulate material from the at least one particulate material supply compartment to the at least one particle delivery unit; and an inductor assembly having a pneumatic source, a flow connection to the at least one particulate material supply compartment for receiving particulate material from the at least one compartment, and an outlet conduit providing an entrained flow of air and particulate material to the metering assembly. 
     The invention in another form is directed to a method of delivering at least one particulate agricultural product from at least one compartment containing the at least one product to a particle delivering unit applying the particle in a field. The method includes steps of supplying the at least one particulate agricultural product from the at least one compartment to an inductor assembly; fluidizing the at least one product in the inductor assembly; conveying the at least one fluidized product to a metering device; metering the at least one conveyed product in the metering device to provide a metered flow of the at least one product; transferring the metered flow of the at least one product to the particle delivering unit; and applying the transferred at least one product in an agricultural field. 
     The invention in still another form is directed to an agricultural applicator implement for applying particulate material in an agricultural field. The agricultural applicator implement includes a tank for containing the particulate material, an inductor assembly receiving particulate material from the tank, an outlet conduit from the inductor assembly; a metering assembly connected to the outlet conduit downstream from the inductor assembly; and a particulate delivery unit receiving metered flow of particulate material from the metering assembly and applying the particulate material in an agricultural field. 
     An advantage of the present pneumatic delivery system is minimizing complications when changing equipment, and if the inductors cover a large spectrum of seed and/or fertilizer types, to use a common tank for many applications. 
     Another advantage is providing a more stable system less prone to adverse impact from variations and interruptions in the fluidized transport of air-entrained products. 
     Still another advantage is providing a system that is adaptable to uses with different types of particulate products and on different types of agricultural implements. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above-mentioned and other features and advantages of this pneumatic delivery system, and the manner of attaining them, will become more apparent and the pneumatic delivery system will be better understood by reference to the following description of embodiments of the pneumatic delivery system taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a perspective view of an agricultural application implement, in the nature of a fertilizer spreader, having a pneumatic delivery system as disclosed herein; 
         FIG. 2  top view of the fertilizer spreader shown in  FIG. 1 ; 
         FIG. 3  is a side view, in simplified form, of the fertilizer spreader; 
         FIG. 4  is an enlarged partially exploded view of a portion of the fertilizer spreader; 
         FIG. 5  is a top view in schematic form of another embodiment of a pneumatic delivery system on a fertilizer spreader; 
         FIG. 6  is a perspective view of a metering device useful for the pneumatic delivery systems disclosed herein; 
         FIG. 7  is a perspective view of another metering device; 
         FIG. 8  is a perspective view of an implement employing a plurality of the metering devices shown in  FIG. 7 ; and 
         FIG. 9  is a perspective view of another agricultural implement, an air seeder, having a pneumatic delivery system as disclosed herein. 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate embodiments of the pneumatic delivery system and such exemplifications are not to be construed as limiting the scope of the invention in any manner. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, and more particularly to  FIGS. 1-3 , there is shown an agricultural application implement  10 , on which a pneumatic delivery system  100  can be used. In the exemplary embodiment shown, application implement  10  is a pneumatic granular fertilizer applicator  10 . As is known in the art, applicator  10  generally includes a large tired transport unit  12  such as truck or tractor, and laterally extending particle delivery booms  14  and  16 , which may be pivoted to a stowed position close to the implement for storage or transport. Each boom  14 ,  16  includes a plurality of boom tubes or conduits terminating at the outboard end in a particle delivering unit, which for fertilizer applicator  10  are a spreading outlet or nozzle. In the exemplary embodiment shown, boom  14  includes eight nozzles  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30  and  32 ; and boom  16  includes nozzles  34 ,  36 ,  38 ,  40 ,  42 ,  44 ,  46  and  48 . Additionally, at the back of applicator  10  there are rear nozzles  50 ,  52 ,  54  and  56  to provide full and complete coverage across the width of implement  10 , include the area between the inboard-most nozzles  18  and  34  of booms  14 ,  16 . Implement transport unit  12  is self-propelled by an engine in an engine compartment  58  and includes an operator cab  60 . In the exemplary embodiment shown, a tank  62  includes compartments  64  and  66  for carrying particulate material to be distributed to and disbursed by nozzles  18 - 56 . Further smaller compartments  68 ,  70  can be provided to supply micro-nutrients or other materials to nozzles  18 - 56 . The supply of particulate material in compartments  64 ,  66 ,  68 ,  70  is replenished periodically from a still larger volume supply vehicle. 
     Fertilizer applicator  10  is illustrative of the types of equipment for which the pneumatic delivery system can be used; however, it should be understood that the pneumatic delivery system may, of course, be employed in conjunction with other agricultural equipment such as tillage, seeding or planting devices, and is useful in distributing particulate material other than fertilizer. 
     With reference now particularly to  FIGS. 3 and 4 , in a simple form thereof, pneumatic delivery system  100  includes an inductor assembly  102  and a metering assembly  104 . Inductor assembly  102  receives particulate material from tank  62  and supplies the particulate material to metering assembly  104 . Metering assembly  104  distributes metered flows of the particulate material for distribution by nozzles  18 - 56 . 
     Inductor assembly  102  can be provided beneath tank  62  to receive particulate material from tank  62  under gravitational flow. Inductor assembly  102  includes a pneumatic source, such as a fan  106 , an inductor  108 , an outlet conduit  110  from inductor  108  and a flow connection  112  to tank  62 . Inductor  108  can be of known design and configuration, such as, for example and not limitation, that shown in U.S. Pat. No. 7,182,029 “Inductor Assembly for a Product Conveying System” or that shown in U.S. Pat. No. 8,534,208 “Product Conveyance System for an Agricultural Implement”. Other types of inductors also can be used. Those skilled in the art will readily understand the manner in which inductor assembly  102  produces a flow of air that combines with particulate material to generate a combined stream of forced air and the particulate material which is discharged through outlet conduit  110 . 
     Metering assembly  104  receives the flow of particulate materials from inductor assembly  102  and provides controlled, metered flow to the nozzles  18 - 56  by managing the air flow that controls particulate fluidization in the inductor, such as known for planters using a vacuum fan to control the quantity seeds going through the inductor. A seed gate also can be used to control fluidization. Various types of metering devices can be used and can be carried by that portion of implement  10  which performs actual material distribution. Accordingly, one type of metering device can be used when distributing particulate material of a first type and a different type of metering device can be used when distributing particulate material of a second type. 
     It should be understood that separate and discrete inductors are provided for the number of compartments in tank  62 , with each such inductor having a separate outlet  110  there from to provide the particulate materials to metering assembly  104 . Further, while  FIG. 4  shows a metering assembly  104  having a single unit distributing metered flow to each of the nozzles  18 - 32  on boom  14 , it should be understood that multiple metering devices within the metering assembly can be provided. 
       FIG. 5  schematically illustrates an implement  200  having a pneumatic delivery system  210 . Implement  200  is similar to implement  10 , having a transport unit  212  and booms  214 ,  216 . A tank  218  includes compartments  220 ,  222 . Pneumatic delivery system  210  includes an inductor assembly  224  having separate inductors  226 ,  228  for compartments  220 ,  222 , respectively. Each inductor  226 ,  228  has an outlet  230 ,  232 , that is connected to each of a plurality of metering devices. Boom  214  is provided with metering devices  234 ,  236 ; boom  216  is provided with metering devices  238 ,  240  and a rear metering device  242  is provided at the rear of a transport unit  212 . Each metering device  234 - 242  receives particulate material flow from each inductor  226 ,  228 . Metering devices  234 - 242  each provide metered material flow to one or more particle delivery unit  244 ,  246 ,  248 ,  250 , and  252  respectively. Particle delivery units  244 - 252  can be nozzles as described previously or can be other types of delivery units such as rotating plates for the distribution of particulate material deposited thereon. 
     The metering devices disclosed herein can be of various types. By way of example and not limitation, a metering device  300  is illustrated in  FIG. 6 . Metering device  300  is provided for metering the flow of four particulate materials, such as may be included in a fertilizer and/or pesticide application. Metering device  300  includes an individual accumulation hopper  302 ,  304 ,  306 ,  308  for each particulate material that is being applied. Hoppers  302 - 308  receive particulate material from inductors (not shown) by way of inductor outlet conduits  310 ,  312 ,  314 ,  316 . Each of the accumulation hoppers  302 - 308  is provided with an air breather  318 ,  320 ,  322 ,  324 , respectively. As known to those skilled in the art, hoppers  302 - 308  provided with breathers  318 - 324  can operate with a pneumatic supply of material thereto in an on-demand fashion. As a particulate material accumulates in one of the hoppers  302 - 308 , the particulate material obstructs the breather  318 - 324  associated with the hopper, thereby stopping the flow of particulate material to the hopper. As the level of particulate material decreases in a hopper  302 - 308 , flow of particulate material thereto will resume. A vacuum inlet as known for planters also can be used. 
     Metered dispensing of particulate material from accumulation hoppers  302 - 308  can be by known means, such as a rotating metering roll  326 . In the exemplary embodiment shown, metering device  300  provides a combined flow of metered particles via a particle mixing drum  328  that receives the individual metered flows from hoppers  302 - 308 , mixes the particulate materials and dispenses the mixed materials to a rotary spreader  330 . The rollers can be separated by some minimal distance, or by a physical barrier or divider. 
     Since metered distribution of material continues even when the flow of particulate material to a hopper is interrupted, normal distribution of the material will continue until the hopper is empty, even if the upstream flow to the hopper is interrupted by plugging or the like. Placing the meter at the end of the material conveying circuit, near the point at which the particulate material is applied, and separating the meter by way of the on-demand hopper system isolates the meter from changes in pressure upstream of the hoppers, such as may occur during temporary plugging and/or plug clearing. 
       FIG. 7  illustrates another metering assembly associated with a rotating applicator. Carousel metering assembly  400  includes an array of individual metering devices  402 ,  404 ,  406 ,  408  which may be compact individual metering units of various types, including rotating rolls, vibrating meters and the like. Metering devices  402 - 408  individually dispense metered particulate material onto a rotary spreader  410 . Metering devices  402 - 408  are supplied with a flow of particulate material via outlet conduits  412 ,  414 ,  416 ,  418 , respectively.  FIG. 8  illustrates the use of five carousel metering assembly&#39;s  400  each receiving particulate material from an inductor assembly  420 . Meters can be driven individually by electric motors, hydraulic motors or the like; or the meters can be linked together mechanically using a variable speed system of clutches, brakes and the like. 
     While the pneumatic delivery systems disclosed so far herein have been primarily with respect to pneumatic fertilizer application equipment commonly referred to as a “floater”, it should be understood that the advantages from the pneumatic delivery systems disclosed herein can be obtained on other types of equipment for applying particulate materials in a field. Planters of various types are known to include an applicator unit, such as a drill or seeder, and may include an air cart having one or more bulk tanks carrying fertilizer and/or seeds to be planted. The pneumatic delivery systems disclosed herein can be provided by way of one or more metering assembly on the planter, and one or more inductor on the air cart. If the air cart is then used with a planter of a different type, or with another type of particle application equipment, adjustments to the metering assembly can be made without the need to adjust the inductor assembly on the air cart. Accordingly, switching from one crop to another crop or from one planter to another planter does not require major adjustment of the inductor assembly on the air cart. 
       FIG. 9  illustrates an agricultural application implement in the form of an air seeder  500  that includes an air cart  502  and an air drill  504 . Air cart  502  includes inductors  506 ,  508 ,  510  to fluidize particulate material contained in each of three separate compartments. Each inductor  506 ,  508 ,  510  is connected to each of a plurality of metering devices  512 ,  514 ,  516 ,  518 ,  520 . Metering devices  512 - 520  meter seeds and/or other particulate material in controlled flows to pluralities of particle delivery units that deposit the seeds and/or other particulate material in the farm field. 
     In using a pneumatic delivery system as disclosed herein, a variety of materials can be applied by a variety of different implements. The particulate material to be applied is contained in one or more compartments. The particulate material or materials are supplied to an inductor assembly wherein the material or materials are fluidized and conveyed to one or more metering device. At the metering device the conveyed product or products are provided in a metered flow and transferred to one or more particle delivery unit, which can be a broadcast spreader, seeder for depositing seeds or other materials across the surface of soil, a row opener unit for depositing seeds or other material in rows, or the like. When advantageous, the metered flows can be combined and the combined flow in appropriate proportions then provided to the particle delivery unit or units. 
     While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.