Abstract:
Nozzle attached to the boom of agricultural sprayers each include an improved air eduction system and discharge slot eliminating the need to change the angle of the boom and nozzle to ensure a comprehensive spray pattern irrespective of boom height and improved penetration of the material sprayed into and under the crop canopy.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    I. Field of the Invention  
           [0002]    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 fluid is evenly dispersed over a broad area.  
           [0003]    II. Description of the Related Art  
           [0004]    Most agricultural sprayers are mounted to a motor vehicle. These sprayers typically include one or more tanks in which material to be applied to a farm field is stored, a boom, a plurality of spray nozzles mounted along the boom, plumbing for carrying materials from the tank to the nozzles, and at least one pump for forcing material from the tank, through the plumbing and out the nozzles.  
           [0005]    Most boom and nozzle arrangements are designed so that the chemicals are sprayed straight down on the plants. However, recent studies suggest that advantages can be achieved if the boom and nozzles are turned to angle the nozzles back about 10 to 20 degrees. One advantage is that angling the nozzles back ensures some overlap of the spray pattern delivered by adjacent nozzles and, thus, more complete chemical coverage. Another advantage is that angling the nozzles helps the chemical reach weeds that may be hidden underneath the foliage of the crop. For example, if one sprays straight down, the chemical may be blocked by the leaves of soybean plants and never reach the weeds hiding beneath these leaves.  
           [0006]    Many boom and nozzle arrangements are designed so that it is either not possible to angle the nozzles back or requires substantial labor or retrofitting to do so. Thus, there is a real need for a nozzle that can be used on a conventional boom and with a traditional nozzle holder for providing all the advantages of angling the boom and nozzles without the labor and expense associated with angling the boom and nozzles.  
         SUMMARY OF THE INVENTION  
         [0007]    The present invention provides a nozzle tip that provides all of the advantages of angling the boom of an agricultural spray system without the cost and labor involved modifying the spray system to angle the boom. The nozzle tip of the present invention can be used with any nozzle cap designed to hold ISO size nozzle tips. The nozzle tip includes an inner member and an outer member which work in combination to generate the desired pattern. The nozzle tip of the present invention uses a unique eduction mixing system and an angled discharge opening to provide all of the benefits without the expense of angling the spray boom. 
       
    
    
       [0008]    Other objects and advantages of the present invention will become apparent from the following detailed description of the preferred embodiment in view of the drawings which are described below.  
       BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    [0009]FIG. 1 is a perspective view of the nozzle of the present invention.  
         [0010]    [0010]FIG. 2 is a front view of the nozzle of the present invention.  
         [0011]    [0011]FIG. 3 is a side view of the nozzle of the present invention.  
         [0012]    [0012]FIG. 4 is a top view of the nozzle of the present invention.  
         [0013]    [0013]FIG. 5 is a bottom view of the nozzle of the present invention.  
         [0014]    [0014]FIG. 6 is a cross-sectional view of the outer member of the nozzle of the present invention.  
         [0015]    [0015]FIG. 7 is a side view of the inner member of the nozzle of the present invention.  
         [0016]    [0016]FIG. 8 is a cross-sectional view of the inner member of the nozzle of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0017]    The nozzle  1  has an outer member  2  and an inner member  3 . The nozzle  1  is designed to fit within a holder or cap (not shown) designed to receive and hold standard ISO nozzles. As such, the nozzle  1  has certain features common with other ISO nozzles.  
         [0018]    For example, the outer member  2  has a flange  4  and a central section  5  each sized and shaped to cooperate with a standard cap design. Specifically, the central section  5  is designed to fit within an opening the cap and the flange  4  engages the surfaces of the cap to ensure the nozzle  1  remains affixed to the cap.  
         [0019]    The nozzle  1  of the present invention, however, is very different from a standard ISO nozzle in a variety of respects. As shown in FIGS.  1 - 6 , the outer member  2  also includes a generally cylindrical extension  6  that terminates in a semi-spherical tip  8 . The tip  8  has a generally V-shaped discharge slot  10  formed by a pair of walls  12  and  14 . The wall  12  is generally parallel to the longitudinally axis of the nozzle  1 . The wall  14  is not parallel to this axis and, instead, extends at an angle in the range of 10° to 20° (and preferably 15°) from the longitudinal axis. To provide a clear indication of which wall is parallel and which wall is angled, an exterior projection  16  is provided. As shown, projection  16  is on the side of the parallel wall  12  and opposite that of the angled wall  14 .  
         [0020]    Another important feature of the outer member  2  is the series of openings  17  between the central section  5  and the cylindrical extension  6 . The openings  17  provide a path for air to be educted into the flow stream. Also, because a plurality of smaller openings  17  are provided, as opposed to a single larger opening, the air is filtered of debris, the chance of clogging the entire area of the openings is reduced, and the air flow into the stream is more uniform.  
         [0021]    The outer member  2  has an inner lumen  18  (see FIG. 6) which is wider in the area of the flange  4 , has a smaller diameter in the area of the central section  5 , and is smaller yet in the area of the extension  6 . Surrounding the lumen  18  in the are of the flange  4  is a channel  19  that is used to lock the inner member  3  to the outer member  2 .  
         [0022]    [0022]FIGS. 7 and 8 show the construction of the inner member  3 . The inner member  3  has a flange  20  having a projection  21  that fits within the channel  19  of the outer member  2 . The inner member  3  also has a central ring  22  and an extension  24 . The space  27  between the extension  24  and the ring  22  is generally open. A pair of posts  25  and  26  hold the ring  22  and extension  24  in spaced apart relation.  
         [0023]    [0023]FIG. 8 shows the shape of the lumen  28  that runs through the inner member  3 . As shown, the lumen  28  has a frusto-conical portion  30  in the area of the flange  20 . As it continues, it narrows to a cylindrical section  32  in the area of the ring  22 . It also has a frusto-conical section  34  in the area of the extension  24 .  
         [0024]    When the inner and outer members are assembled, the end of the extension  24  of the inner member  3  resides within the extension  6  of the outer member  2 . Also, a chamber is created between the outer wall of the extension  24  of the inner member  3  and the inner wall of the central section  5  of the outer member  2 . This chamber, in combination with the openings  17  of the outer member  2  and the space between the ring  22  and the extension  24  of the inner member  3 , creates a flow path through which air can be educted into the stream of liquid passing through the nozzle  1 . That stream of liquid passes through the lumen  28  of the inner member  3 , mixes with the air, passes through the extension  6  of the outer member  2  and then through the slot  10 . The nature of the flow path and the shape of the slot  10  give the fluid exiting the nozzle  1  the same motion as if the boom were tipped approximately 15°.  
         [0025]    Nozzles constructed in accordance with the preferred embodiment offer a variety of advantages. First, such nozzles eliminate the need to change the angle of the boom to ensure a comprehensive spray pattern irrespective of the height of the boom. Second, such nozzles are preset to provide the correct delivery angle for the chemicals providing improved penetration into the crop canopy so the chemicals reach weeds hiding under crop foliage. Third, the nozzles of the present invention fit standard booms and standard nozzle body holders or caps. Fourth, no tools are needed to change the nozzles. Fifth, the nozzles can be used to provide either an angled back or an angled forward delivery of chemicals and are clearly marked to assist in assembly and installation to achieve whichever type of angled delivery is required. Sixth, the design of the eduction system and the slot design permit the nozzle  1  to be used effectively at lower operating pressure to deliver a more open spray pattern. Finally, the preferred embodiment can be constructed in a variety of sizes either to fit different ISO or other sized caps or holders.  
         [0026]    While the preferred embodiment described above shows the wall  14  angled of 15° from the longitudinal axis of the nozzle  1 , the wall  14  can be set at different angles (preferably in the range of 10° to 20°) to modify the discharge pattern and impart a different spray angle. These and other changes can be made to the preferred embodiment of the invention without departing from the scope of the invention as defined by the following claims.