Abstract:
The present disclosure relates to a system and method for spraying a target object. A recapture shell may partially contain the target object and mitigate dispersal of overspray. A leading front of higher-than ambient air pressure and a trailing front of lower-than ambient air pressure are created to partially isolate recirculating air within a target space in the recapture shell to enhance spray coverage and mitigate spray loss. Embodiments of the present disclosure may be used for agricultural, automotive, aerospace, and other applications to emit, contain, and/or recapture a spray.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority under 35 USC §119 to U.S. Provisional Patent Application Ser. No. 61/630,475, filed on Dec. 13, 2011, and titled “Hard Bodied Recapture Sprayer for Orchards,” the entire contents of which are hereby incorporated by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates generally to a system and method for spraying, containing, and recapturing a spray discharge. More particularly, the disclosure relates to a shell that partially encompasses a target object, emits a spray, and mitigates overspray. 
       BACKGROUND 
       [0003]    Spray recapture systems have been used in the past to prevent overspray of paint, agricultural chemicals including fertilizers, fungicides, herbicides, pesticides, and other types of spray discharge. Typically, traditional recapture systems are limited to small objects or to use in a contained space. Traditional agricultural sprayers may not include means for containment of overspray and accordingly, overspray may escape any target areas, especially if application takes place in a windy outdoor area. 
         [0004]    In some cases, spray discharge includes volatile organic compounds (“VOCs”), which may be dangerous to human health and/or the environment. What is needed, therefore, is a method and system of containing and collecting spray while enhancing spray coverage on a target object and minimizing overspray and drippage. 
       SUMMARY 
       [0005]    In one embodiment, a spray recapture shell is disclosed. The spray recapture shell has an outer shell surface having a partially-encompassed spray volume, at least one spray nozzle on an inside surface of the spray recapture shell, a leading edge of the partially-encompassed spray volume having a higher-than ambient pressure, and a trailing edge of the partially-encompassed spray volume having a lower-than ambient pressure. 
         [0006]    In another embodiment, a method of spraying a target object is disclosed. The method includes moving a shell to partially encompass the target object within a partially-encompassed spray volume, creating a leading edge of the partially-encompassed spray volume having a higher-than ambient pressure, creating a trailing edge of the partially-encompassed spray volume having a lower-than ambient pressure, and applying a spray to the target object. 
         [0007]    The present disclosure will now be described more fully with reference to the accompanying drawings, which are intended to be read in conjunction with both this summary, the detailed description, and any preferred or particular embodiments specifically discussed or otherwise disclosed. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of illustration only so that this disclosure will be thorough, and fully convey the full scope of the disclosure to those skilled in the art. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    This disclosure may be understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements, and in which: 
           [0009]      FIG. 1  is a perspective view of a recapture sprayer shell according to an embodiment of the present disclosure; 
           [0010]      FIG. 2  is a side view of a recapture sprayer shell according to an embodiment; 
           [0011]      FIG. 3  is a cutaway drawing depicting a bottom-side perspective view of a recapture sprayer shell according to an embodiment; 
           [0012]      FIG. 4  is a rear view of a recapture sprayer shell according to an embodiment; 
           [0013]      FIG. 5A  depicts multiple recapture sprayer shells in use; and 
           [0014]      FIG. 5B  is an overhead view of multiple recapture sprayer shells in use. 
       
    
    
     DETAILED DESCRIPTION 
       [0015]    In the following description, reference is made to the accompanying drawings that form a part thereof, and in which is shown by way of illustration specific exemplary embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the concepts disclosed, and it is to be understood that modifications to the various disclosed embodiments may be made, and other embodiments may be utilized, without departing from the spirit and scope of the present disclosure. The following detailed description is, therefore, not to be taken in a limiting sense. 
         [0016]    An objective of embodiments of the present disclosure is to apply a spray to a target object, contain the spray within a shell, and recapture the spray while minimizing overspray, spill, and loss. In embodiments, the spray comprises a chemical-laden stream of air. Alternatively, the spray comprises a liquid, an aerosol, or a combination thereof. In alternative embodiments, the spray comprises an electrostatic spray. Such embodiments may include one or more nozzle adapted to emit an electrostatic spray. Chemicals may comprise a fertilizer or like plant nutrient, a pesticide, an herbicide, a fungicide, or any other chemical that may be applied by a spray and for which spray recapture is desired. In alternative embodiments, chemical in the spray include paints, de-icing compounds, and the like. Embodiments of the present disclosure comprise a shell adapted to partially encompass a target object. In embodiments, the shell comprises spray nozzles, positive air pressure nozzles, and spray recapture ports. 
         [0017]    With reference to  FIGS. 1 and 2 , an embodiment of the present disclosure comprises spray recapture shell  100 . In the embodiment depicted, shell  100  comprises a curved horseshoe arch shape, being laterally narrower at its bottom than at its mid-span. Shell  100  comprises a covering that partially encompasses a target space  110 . In alternative embodiments, the surface of shell  100  comprises a curved or angular-shaped arch. In alternative embodiments, shell  100  comprises a shape and size appropriate to partially or fully contain an intended target object. Spray recapture shell  100  comprises external shell surface  120 . Shell  100  may selectively be sized to correspond to a target object. For example, if the target objects comprise trees having a typical height of 20 feet, an embodiment of shell  100  may be used that has an approximate height of slighter greater than 20 feet. 
         [0018]    In embodiments, external shell surface  120  comprises a skin material that has resistance to ultraviolet light and/or other elements to which the shell  100  may be exposed. In embodiments, external shell surface  120  comprises a metal skin. In alternative embodiments, external shell surface  120  comprises other resistant and/or durable materials of manufacture. External shell surface  120  may comprise composites of various materials, including metal/plastic composites. In embodiments, inner skin surface  130  comprises a solvent-resistant material such as polyethylene, for example high density polyethylene (“HDPE”). In alternative embodiments, inner skin surface  130  may comprise other chemical-resistant materials, depending on the anticipated use. Alternative embodiments comprise an inner skin surface  130  manufactured from stainless steel. 
         [0019]    As depicted in  FIG. 3 , spray recapture shell  100  comprises spray nozzles  140 . In the embodiment depicted, spray nozzles  140  are staggered in two rows around the inner surface  130  of spray recapture shell  100 . In the embodiment depicted, each row of spray nozzles  140  roughly lies in a plane that is normal to spray recapture shell&#39;s  100  direction of travel. In the embodiment depicted, the distribution of spray nozzles  140  around the inner surface  130  of the spray recapture shell  100  provides approximately 270 degrees of encompassment around the target space  110 . In alternative embodiments, a spray recapture shell having a narrower gap between the wheels  150 ,  155  may have a greater encompassing angle and may nearly approach 360 degrees. Conversely, a wider gap between wheels  150 ,  155  may translate into a lower encompassing angle. In other embodiments, spray nozzles  140  are distributed in alternative patterns on inner surface  130 . As shown in  FIG. 1 , wheels  150 ,  155  have free-rotation from each other. 
         [0020]    In the embodiment depicted in  FIG. 4 , spray nozzles  140  are each directed off center within shell  100  by roughly 15 degrees. Such offset of spray nozzles  140  may provide increased circulation of spray within recapture shell  100 . In alternative embodiments, spray nozzles  140  are offset at other angles. In another embodiment, spray nozzles  140  have no offset and are accordingly directed at an approximate center of spray recapture shell  100 . In other embodiments, spray nozzles  140  are adjustable to meet any local requirements or uses of spray shell  100 . 
         [0021]    Referring now to  FIGS. 1 and 3 , spray recapture shell  100  further comprises air nozzles  160  located on inner surface  130 . In the embodiment depicted, air nozzles  160  are located near the rear of shell  100  and near the bottom of shell  100 . Air nozzles  160  are directed upward and forward toward a leading edge  170  of spray recapture shell  100 . In alternative embodiments, air nozzles  160  are located at other points on spray recapture shell  100  that allow air nozzles  160  to direct a stream of air toward leading edge  170 . 
         [0022]    Air nozzles  160  are in fluid communication with an air compressor, which is adapted to supply a stream of air through a network of hoses to air nozzles  160 . The air compressor may be located on or within spray recapture shell  100  or on a tow vehicle such as a tractor. For applications where a high degree of air movement is called for, such as a shell  100  having a relative large target space  110 , multiple air compressors may be used. Alternatively, air flow through nozzles  160  are driven by an air generator or blower assembly. 
         [0023]    As depicted in  FIG. 3 , recapture port  180  is located at or near the top of the inner surface  130  near the rear of spray recapture shell  100 . In alternative embodiments, recapture ports  180  are located at other locations on inner surface  130  in spray recapture shell  100 . Recapture port  180  is in fluid communication with a vacuum mechanism and with a recapture tank. The recapture tank may be located on spray recapture shell  100  or on a tow vehicle. 
         [0024]    Spray recapture shell  100  comprises drip catch edge  190  at lower edges of inner surface  130 . Drip catch edge  190  comprises a small flange along a bottom edge of inner surface  130  and is adapted to channel drips to drip catch inlet  200 . Drip catch inlet  200  is in fluid communication with one or more internal hoses connected to a collection tank and/or pump to recirculate drippage from the inner surface  130 . Drippage may be pumped to a drip holding tank, filtered and stored at a central spray tank, and/or pumped back to spray nozzles for reapplication to a target object. 
         [0025]    Referring now to  FIG. 1 , spray recapture shell  100  comprises tow tongue  210 . Tow tongue comprises tow hitch  220  with offset  230  to create sufficient clearance between a tow vehicle and each target object. The size of tow offset  230  may be determined by the size of target objects, the size of tow vehicle, and/or the size of spray recapture shell  100 . 
         [0026]    As depicted in  FIG. 2 , spray recapture shell  100  comprises an extended tail section  240 . Tail section  240  overhangs beyond target space  110  and comprises curved cutout  250 . In other embodiments, tail section  240  and cutout  250  comprise alternative shapes and forms, such as a non-curved rear edge. 
         [0027]    Embodiments of the spray recapture shell  100  comprise skeleton frame members (not depicted). Frame members may be sandwiched between inner shell surface  130  and external shell surface  120  to provide structural rigidity to shell  100  to transmit forward-motion forces across the structure of shell  100 . Angle iron or other durable and sufficiently strong material may be used for frame members. 
         [0028]    A tank to hold chemical spray, fluid pump for pressurizing the chemical spray, air compressor, and/or additional equipment may be located on towing vehicle or on the spray recapture shell. Such equipment may be powered by the PTO or other source of power. 
         [0029]    Alternative embodiments comprise a trimmer device at the leading edge of spray recapture shell  100 , so that any plants that comprise target object may be trimmed if they might not otherwise fit within target space  110 . The trimmer device may be powered by a power take off (“PTO”) shaft from a tow vehicle, by hydraulic power driven by the PTO, or other source of power. 
         [0030]    As depicted in  FIGS. 5A and 5B , embodiments of the present disclosure comprise multiple spray recapture shells  100  fixed along a support structure  260 , so that multiple rows of target objects may be sprayed at a time. Such embodiments may not include wheels, but hang freely from support structure  260 . In embodiments, external surface  120  and internal surface  130  may comprise a relatively flexible material. Any selected number of spray recapture shells  100  may be thus fixed to each other in order to meet particular circumstances and factors. 
         [0031]    In embodiments of the present disclosure, hydraulic power driven by PTO or other power source may be applied to drive the outside wheel  155 . A converter may speed up or slow down the outer wheel  155  to compensate for turning or other speeds of tow vehicle. Alternatively, outer wheel  155  may be powered by an electric motor or other means. 
         [0032]    In operation, spray recapture shell  100  is towed by tow vehicle through an orchard, field, or other location where one or more objects are to be sprayed. Due to the tow hitch offset  230 , spray recapture shell  100  may not be directly behind tow vehicle, but rather is too one side thereof. Accordingly, tow vehicle may drive along a row of trees or other target objects and spray recapture shell  100  may pass over the top of each target object, with wheels  150 ,  155  straddling the target object. As spray recapture shell  100  approaches a row of target objects, an operator may activate a spray pump, vacuum pump, and air compressor. 
         [0033]    Air nozzles  160  eject a stream of air directed near the front of spray recapture shell  100 . Recapture port  180  apply suction from an air vacuum mechanism. As a result of such action at air nozzles  160  and recapture port  180 , a front of higher-than ambient air pressure is created at the front edge  170  of the target space  110  encompassed by spray recapture shell  100  and a front of lower-than ambient pressure is created at the rear edge of the target space  110  encompassed by spray recapture shell  100 . A zone of neutral pressure may be created within the target space  110  between the high-pressure front and the low-pressure front. The higher-than ambient air pressure front generally defines a transition zone across the front opening of spray recapture shell  100  and may act as a barrier to prevent ingress of bulk ambient air as the spray recapture shell  100  moves forward. Accordingly, a substantially isolated pocket of circulating air may be maintained within the target space  110 , so as to minimize or reduce the potential for air that is circulating within the target space  110  to drift out of the spray recapture shell  100 . 
         [0034]    A spray pump pressurizes the chemical composition stored in the spray tank and thereby causes spray nozzles  140  to spray chemical. As air within the partially-enclosed target space  110  is circulating, sprayed chemical may be carried around within the space  110  and into any target object therein. Some amount of the sprayed chemical may stick to various surfaces of the target object. Due to the recirculation of air within the target space  110 , the chemical spray may come into contact with a relatively high amount of surface of the target object. Suction from recapture port  180  may pull overspray into port  180  for recirculation, recycling, or storage. Chemical spray that contacts an inner surface  130  may drip downward and be channeled through drip catch edge  190  to drip catch inlet  200 . Embodiments of the present disclosure comprise a drip catch pump, which pressurizes liquids that entered drip catch inlet  200  and transmits such liquids through one or more filters, back into chemical storage tank, back to spray nozzles to re-spray, and/or into a drip holding tank. 
         [0035]    According to embodiments of the present disclosure, recapture shell  100  may be used to spray chemical in agricultural application on trees, vineyards, smaller crops, or other types of agricultural uses. Alternative embodiments of the present disclosure may be utilized for spraying paint in automotive, aerospace, or like applications. Embodiments may be used for spraying de-icing spray in aerospace or like applications, spraying paint on road surfaces, or other applications wherein a spray may be applied to a target object. 
         [0036]    As would be understood by one of ordinary skill in the art having the benefit of this disclosure, advantages of embodiments disclosed herein may include usage of lower pressures and/or lower volumes of chemicals than traditional sprayers, while achieving as good or better overall coverage on target objects. Thus, application of embodiments disclosed herein may result in lower cost and decreased environmental harm. Additionally, the spray recapture shell  100  may allow application of spray in high-wind environments which may not be feasible with current technology. For example, spray recapture shell  100  may shelter the target space  110  from disturbance by side winds. Airflow rates from air nozzle  160  may be adjusted to compensate for high front- or rear-facing winds. 
         [0037]    Although the present disclosure uses terms of certain embodiments, other embodiments will be apparent to those of ordinary skill in the art having the benefit of this disclosure, including embodiments that do not provide all of the benefits and features set forth herein, which are also within the scope of this disclosure. It is to be understood that other embodiments may be utilized, without departing from the spirit and scope of the present disclosure.