Abstract:
A nozzle for delivering fluid evenly over a wide swath is disclosed. The nozzle has an elongated tip which has a stepped slot. Air eduction is also provided to reduce drift of the fluid being delivered through the nozzle.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    I. Field of the Invention  
           [0002]    This application is a continuation-in-part and claims the priority of U.S. application Ser. No. 09/968,411, filed Sep. 27, 2001 and entitled “Nozzle for Agricultural Sprayers”.  
           [0003]    The present invention relates to the application of crop protection chemicals such as fertilizers, herbicides, insecticides, fungicides and the like. More specifically, the present invention relates to nozzle arrangements for fluid spray applicators that ensure that the fluid is evenly delivered over a broad area.  
           [0004]    II. Description of the Related Art  
           [0005]    Most agricultural fluid spray application systems are mounted to the back of a vehicle. These systems typically include one or more tanks in which material to be applied is stored, an extended boom which carries a plurality of nozzles along the length of the boom, plumbing for carrying the material from the tanks to the nozzles, and at least one pump for forcing the material from the tanks through the plumbing and out the nozzles. There seems to be constant pressure placed upon equipment manufacturers to build larger booms so that it takes less time for people involved in chemical application to apply agricultural chemicals to a given area. Booms now reach more than 80 feet in length and weigh more than a ton. While very even distribution of the agricultural chemicals can be achieved with this equipment, there are certain inherent problems. These problems are exacerbated as booms get longer.  
           [0006]    Booms of an extended length cannot simply be bolted to a vehicle. Complex suspension systems are required to ensure that the boom is properly supported. Shock absorbers must also be provided because farm fields, range land, pastures, golf courses, etc. where such equipment is used are not flat. Vehicles carrying the boom often encounter uneven terrain, ruts, rocks or other obstacles. These all can impart motion to the vehicle which is exacerbated over the length of the boom.  
           [0007]    Boom leveling systems also must be provided, particularly if the vehicle is operating on a hillside. Quality boom leveling systems will keep the boom parallel to the ground. This is important for at least three reasons. First, if the boom is not parallel to the ground, the delivery of the chemicals is uneven. Second, if an end of the boom contacts the plants being treated, the plants can be damaged. Third, if the end of the boom contacts the ground, the boom can be damaged.  
           [0008]    Agricultural equipment, including boom type sprayers, often need to be transported on public roads. A vehicle with an 80 foot boom in its extended position cannot simply be driven down a public road. Thus, booms must be built to incorporate a series of hinge sections. This greatly increases the cost of the boom.  
           [0009]    In addition to the cost added by incorporating proper suspension, proper shock absorption, proper leveling and proper boom-folding technology, use of an extended boom is not always suitable. This is particularly true when spraying utility and transportation right-of-ways, nursery and foresting stock, or orchards and vineyards. Significant issues arise when any obstacle is encountered such as road signs, bridges, fences, trees, or the like.  
           [0010]    Many of the problems outlined above can be overcome either by reducing the length of the boom or eliminating the boom altogether. Thus, in recent years there have been efforts to develop boomless sprayer type applicators. Yet these boomless sprayers have problems of their own. For a variety of reasons, no one to date has been able to develop a boomless sprayer that delivers the chemicals as evenly and accurately as desired. Even and accurate delivery of the chemicals not only can serve to decrease chemical costs and improve crop yields, it also has other environmental benefits.  
           [0011]    There is, thus, a real need for a nozzle arrangement that can be used either to provide a boomless spray system or to extend the reach of spray systems incorporating booms. Such a nozzle must be able to deliver agricultural materials evenly, uniformly, accurately, precisely and efficiently over a broad area. Such a nozzle must also be durable and designed so worn parts can be easily replaced.  
         II. SUMMARY OF THE INVENTION  
         [0012]    The present invention relates to nozzles for agricultural sprayers. One object of the invention is to provide such a nozzle which will provide even distribution of agricultural chemicals.  
           [0013]    Another object of the invention is to provide such a nozzle capable of delivering suitably large quantities of agricultural chemicals over a short period of time.  
           [0014]    Still another object of the invention is to provide a nozzle capable of evenly distributing the chemicals over a desired swath that can reach  30  feet in width or more.  
           [0015]    A further object of the invention is to provide a nozzle that provides not only uniformity of spray over a wide area, but also sufficient accuracy of product delivery to ensure that the chemicals are sprayed only where intended.  
           [0016]    Another object of the present invention is to provide a nozzle which is durable.  
           [0017]    Still another object of the present invention is to provide a nozzle which has wear parts that are easily replaceable when necessary.  
           [0018]    A further object of the invention is to provide a nozzle that not only meets each of the foregoing objectives, but does so over a wide range of spray widths and spray flow rates.  
           [0019]    Each of the foregoing objects of the invention are achieved by providing a unique nozzle arrangement through which agricultural chemicals can be delivered. In one embodiment, the nozzle has a body member, a flow regulator, a spray tip, and a cap. In another embodiment, a separate air eductor is also provided. The design of the spray tip is such that fluid existing the tip does so in a way that ensures accuracy and uniformity of delivery over a wide swath.  
           [0020]    Other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiments in view of the drawings which are briefly described below. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]    [0021]FIG. 1 is a perspective view showing a nozzle designed in accordance with the present invention.  
         [0022]    [0022]FIG. 2 is an exploded view showing the components of the nozzle shown in FIG. 1.  
         [0023]    [0023]FIG. 3 is a perspective view of the spray tip of the nozzle shown in FIG. 1.  
         [0024]    [0024]FIG. 4 is a front view of the spray tip shown in FIG. 3.  
         [0025]    [0025]FIG. 5 is a bottom view of the spray tip shown in FIG. 3.  
         [0026]    [0026]FIG. 6 is a top view of the spray tip shown in FIG. 3.  
         [0027]    [0027]FIG. 7 is a cross-sectional view of the spray tip shown in FIG. 3.  
         [0028]    [0028]FIG. 8 is a cross-sectional view of the spray tip connector shown in FIG. 1.  
         [0029]    [0029]FIG. 9 is a cross-sectional view of the cap of the nozzle shown in FIG. 1.  
         [0030]    [0030]FIG. 10 is an exploded view showing a first alternative embodiment.  
         [0031]    [0031]FIG. 11 is a top view showing the spray tip connector and regulator disk of the embodiment shown in FIG. 10 in assembled relation.  
         [0032]    [0032]FIG. 12 is an exploded view showing a second alternative embodiment of the present invention.  
         [0033]    [0033]FIG. 13 is an exploded view showing a third embodiment of the present invention.  
         [0034]    [0034]FIG. 14 is a cross-sectional view of the embodiment of FIG. 13 when the components are assembled. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0035]    FIGS.  1 - 9  show a first embodiment of the nozzle of the present invention. As shown, the nozzle includes a spray tip  1 , a spray tip connector  2  and a cap  3 . Each of these components is discussed in greater detail below.  
         [0036]    The spray tip  1  includes a base  10  and an elongated member  12 . The base  10  is at the upstream end  14  of the spray tip  1  and includes a projection  16  and a flange  18 . The elongated member  12  extends from the base  10  and terminates at the downstream end  20  of the spray tip  1 . The elongated member includes a back wall  22  and a pair of opposing side walls  24  and  26 . The front  28  is open as discussed below. Also present are three exterior stiffeners  30 ,  32  and  34  which provide rigidity to the walls  22 ,  24  and  26 . This serves to strengthen the entire spray tip.  
         [0037]    Extending the entire length of the spray tip  1  is an open slot  40 . The slot  40  is open through the upstream end  14 , the downstream end  20  and the entire front  28 . Located within the slot  40  and projecting toward the center of the slot  40  from each side  24  and  26  are three steps. These steps may, but do not necessarily, project toward the center of the slot  40  from the back  22  as well. As shown, steps  42 ,  44  and  46  project inwardly from sides  24  and  26 . As such, the slot  40  is widest between the upstream end  14  and the step  42 . The slot  40  is narrowest between the downstream end  20  and the step  46 . The step  42  generally runs parallel to (or, as shown, is contiguous with) the upstream end  14 . The steps  44  and  46  run generally parallel to each other, but not parallel to either the downstream end  20  or the upstream end  14 . Near the back  22 , the steps are nearer to the downstream end than they are near the front  28 . The steps  44  and  46  preferably slope at an angle of approximately 60□ from near the back  22  toward the front  28 . Steps  44  and  46  also included an arc. As shown, these arcs are  45  and  47 . The slot  40  is also tapered from front to back so that it is slightly wider near the back wall  22 . This taper can be adjusted to alter the spray pattern achieved by the nozzle.  
         [0038]    The spray tip connector  2  includes a pair of threaded members  50  and  52  projected in opposite directions from a nut-shaped member  54 . Threaded member  50  can be used to attach a tube (not shown) such as a hose or pipe to the nozzle. A lumen  56  runs through the center of the base  2 . The threaded member  52  cooperates with threads on the cap  3  to secure the spray tip  1  in place. As shown in FIG. 9, the cap  3  has an open channel  60  through which the elongated member  12  of the spray tip  1  can pass. To assemble the nozzle, the projection  16  of the spray tip  1  is inserted into the lumen  56  until the flange  18  engages the upstream end  53  of the spray tip connector  2 . The elongated member  12  of the spray tip  1  is inserted through the open channel  60  of the cap  3  until the flange  18  engages the shelf  61  of the cap  3 . The threads of the cap  3  and threaded member  52  are used to join the spray tip connector  2  to the cap  3 . When the cap  3  and spray tip connector  2  are tightened, the flange  18  engages surfaces  53  on the spray tip connector  2  and surface  61  on the cap  3  to ensure proper alignment of the parts and a tight fit. When so assembled, a slight gap may exist between the projection  16  of the spray tip  1  and interior structures (such as  55 ) in the lumen  56  of the spray tip connector  2 . Such a gap may serve to provide a larger chamber or zone in which liquid and air can mix prior to liquid being ejected through the spray tip  1 . Of course, such mixing of liquid and air occurs in the spray tip itself.  
         [0039]    To provide proper flow of liquid through the spray tip  1 , a flow regulator  62  can be provided. This flow regulator  62  can be integrally formed within the lumen  56  of the spray tip connector  2  as shown in FIG. 8. Preferably, however, the flow regulator  62  will be a separate component.  
         [0040]    As shown in FIG. 10, a flow regulator  62  is provided. The flow regulator  62  is a separate disk  64  with an orifice  66  through it. The flow regulator is designed to reside within the lumen  56  of the spray tip connector  2  so that it can restrict the flow of liquid into the spray tip  1 . Ideally, the orifice  66  will be non-symmetrical rather than perfectly round. An oblong configuration, for example, not only restricts the volume of liquid entering the stray tip, but also permits one to direct or steer the flow stream to affect the way it enters the spray tip. To ensure that the stream is properly directed, the disk  64  can have a keying element  65  that meshes with a keying element on either the spray tip  1  or the spray tip connector  2 .  
         [0041]    When the nozzle described above is used, superior distribution of the liquid is achieved. The distribution is even over the whole swath. The swath is wide enough to equal that of many boom arrangements. The chemicals are delivered at a sufficient rate to provide efficient application. A plurality of such nozzles can be used to increase the efficiency of the system or provide a wider swath than can be achieved with a single nozzle.  
         [0042]    As the liquid is pumped through the nozzle, air is educted into the flow stream through the slot  40  and mixes with the liquid before the liquid is dispensed. This produces large, air-filled droplets of liquid. The larger droplets reduces drift of the liquid permitting precise application.  
         [0043]    While the mixing that occurs by air being drawn through the slot and mixed with the liquid before it is ejected is sufficient for many applications, the quantity of air mixed with the liquid can be increased by providing a separate air eductor upstream of the spray tip. This arrangement is shown in FIG. 12.  
         [0044]    As shown, the air eductor  80  resides in the liquid flow path between the spray tip  1  and the spray tip connector  2 . It includes an interior chamber in fluid communication with both the lumen  56  of the spray tip connector  2  and the slot  40  of the spray tip  1 . The air eductor  80  also includes one or more air entry channels  82  in communication with the interior chamber. As liquid passes under pressure through the interior chamber, air is drawn through the air entry channels  82  into the chamber and mixes with the liquid.  
         [0045]    [0045]FIGS. 13 and 14 are provided to show still another embodiment of the present invention. Like the embodiments shown in FIGS.  1 - 12 , this embodiment includes a spray tip  1 , spray tip connector  2 , and a cap  3 . This embodiment also includes a flow regulator insert  90  and an O-ring  100 . The cap  3  is identical to the cap shown in connection with the previously described embodiments. However, changes have been made to the spray tip  1  and spray connector  2  to accommodate the flow regulator insert  90  and O-ring  100 .  
         [0046]    As shown in FIG. 13, the spray tip  1  has a base  10 , an elongated member  12  and a flange  18 . The projection  16  (shown in the previously described embodiments) has been eliminated from the spray tip  1 . The exterior of the spray tip connector  2  of the embodiment of FIGS. 13 and 14 is the same as that shown in the drawings related to the embodiments discussed above. However, a comparison of FIG. 8 with FIG. 14 shows that the inside diameter of the flow regulator  62  has been made larger in the embodiment shown in FIGS. 13 and 14.  
         [0047]    The changes discussed in the preceding paragraph were made to accommodate the use of the flow regulator insert  90  and O-ring  100 . As shown in FIG. 13, the flow regulator insert  90  includes an upstream extension  91 , an O-ring seat  92 , an insert flange  93  and a downstream extension  94 . A lumen  95 , open to opposite ends of the insert  90 , extends its entire length. The outside diameter of the upstream extension  91  must be less than the inside diameter of the flow regulator  62  of the spray tip connector  2 .  
         [0048]    When assembled, the O-ring  100  is slid over the end of the upstream extension  91  and resides around the O-ring seat  92  in contact with the upstream side of the insert flange  93 . The upstream extension  91  is then inserted into the flow regulator  62  of the spray tip connector  2  until the O-ring  100  makes contact with seating surface  55  of the spray tip connector  2 . The purpose of the O-ring  100  is to provide a seal between the spray tip connector  2  and the flow regulation insert  90 . Next, the downstream extension of flow regulation insert  90  is inserted into the slot  40  of the spray tip  1 . When so assembled, the downstream extension  94  extends approximately ¾ of the length of the spray tip  1 . Finally, the cap  3  is slid over the spray tip  1  and tightened to the threaded member  52  of the spray tip connector  2  to complete assembly of the nozzle. The nozzle can then be attached to a hose using the threaded member  50  of the spray tip connector  2 .  
         [0049]    In the embodiment of FIGS. 13 and 14, flow out of the nozzle is controlled by the shape of the spray tip  1  and the length of insert  90  as well as the shape of the walls of its lumen. For example, a camber  96  can be created in the area where the liquid exits the insert  90  to improve backfilling of the spray pattern. Changes to the length of insert  90  and the shape of the walls of its lumen can be made without deviating from the invention.  
         [0050]    Several advantages are provided by the embodiment shown in FIGS. 13 and 14. First, because the downstream extension  94  of insert  90  extends up into the spray tip  1 , the flow of liquid is directed to the working end of the spray tip  1  resulting in greater consistency and control of dispersion of the liquid by the nozzle. Second, the O-ring  100  prevents unintended leakage of liquid from the spray tip connector  2  to the spray tip  1 . Such leakage, if permitted, can adversely affect the spray pattern of the nozzle. Third, the positioning of the spray tip  1  and insert  90  reduces the chance of misalignment of the liquid stream to the steps located within the slot  40 . Fourth, the number of impingement steps can be reduced making construction of the spray tip  1  easier. In fact, only one step may be needed when insert  90  is used. Fifth, the camber in the area where the liquid exits the insert  90  results in improved backfilling of the spray pattern so that the quantity of liquid delivery is substantially consistent throughout the entire pattern.  
         [0051]    While the various embodiments shown all include a separate spray tip, spray tip connector and cap, various components can be integrally molded without deviating from the scope and spirit of this invention. For example, the spray tip and spray tip connector can be integrally molded. When this is the case, and with slight modifications to the design, there is no need to provide a cap. Since these and other changes could be made by one of ordinary skill in the art using this specification as a guide, the foregoing description is not intended to be limiting and the inventor seeks to protect all that is covered by the following claims, including a full range of equivalents.