Abstract:
A chemical delivery system having a body defining a main fluid flow passage through which a fluid passes and a storage tank for holding a chemical. An inlet nozzle delivers a quantity of the fluid in the main fluid flow passage to the storage tank to be mixed with the chemical and an outlet nozzle return a quantity of the fluid mixed with the chemical from the storage tank to the main fluid flow passage. An adjustment dial having a plurality of orifices of varying diameter that are capable of being individually placed into relation with the inlet nozzle may be used to control the amount of fluid that enters the first inlet nozzle from the main fluid flow passage. Furthermore, an outlet nozzle trap in fluid communication with a vent port of the outlet nozzle may be placed in fluid communication with a fill control port of the inlet nozzle. The fill control port is used to direct fluid to the outlet nozzle trap to control venting of air from the storage tank to the main fluid flow passage via the vent port.

Description:
RELATED APPLICATION INFORMATION 
     This application is a continuation-in-part of U.S. patent application Ser. No. 10/173,284, filed Jun. 17, 2002, U.S. Pat. No. 6,546,949 which is a continuation of U.S. patent application Ser. No. 09/895,629, filed on Jul. 2, 2001, U.S. Pat. No. 6,453,935 both of which are incorporated herein by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates generally to chemical delivery systems and, more particularly, to a hose-end chemical delivery system. 
     Hose-end chemical delivery systems for spraying chemicals such as insecticides, herbicides, and fertilizers are known in the art. For example, U.S. Pat. No. 4,475,689 describes a variable dilution ratio hose-end sprayer having a rotatable selector dial. Formed in the rotatable selector dial is a plurality of orifices. The orifices are adapted to intersect an output fluid passageway that extends from a fluid container to a mixing chamber. The mixing chamber is provided for mixing selected amounts of fluid from the fluid container with water that enters the mixing chamber from the hose to which the delivery system is attached. The diameter of each orifice of the rotatable selector dial is proportioned to provide a desired final dilution ratio of the fluid to be siphoned from the fluid container. The orifices extend through the selector dial and lie on a circle concentric with the axis of the selector dial. The orifices also have a radius selected to intersect the axis of the output fluid passageway. 
     SUMMARY OF THE INVENTION 
     An improved chemical delivery system is described having a body defining a main fluid flow passage through which a fluid passes and a storage tank for holding a chemical. An inlet nozzle delivers a quantity of the fluid in the main fluid flow passage to the storage tank to be mixed with the chemical and an outlet nozzle is used to return a quantity of the fluid mixed with the chemical from the storage tank to the main fluid flow passage. An adjustment dial having a plurality of orifices of varying diameter that are capable of being individually placed into relation with the inlet nozzle may be used to control the amount of fluid that enters the inlet nozzle from the main fluid flow passage. Furthermore, an outlet nozzle trap in fluid communication with a vent port of the outlet nozzle may be placed in fluid communication with a fill control port of the inlet nozzle. The fill control port is used to direct fluid to the outlet nozzle trap to control venting of air from the storage tank to the main fluid flow passage via the vent port. 
     A better understanding of the objects, advantages, features, properties and relationships of the invention will be obtained from the following detailed description and accompanying drawings which set forth illustrative embodiments and which are indicative of the various ways in which the principles of the invention may be employed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a better understanding of the invention, reference may be had to preferred embodiments shown in the attached drawings in which: 
     FIG. 1 illustrates a cross-sectional view of an exemplary hose-end chemical delivery system constructed in accordance with the principles of the subject invention; 
     FIG. 2 illustrates a top view of an exemplary cap of the hose-end chemical delivery system of FIG. 1; 
     FIG. 3 illustrates a top view of an exemplary selector dial of the hose-end chemical delivery system of FIG. 1; 
     FIG. 4 illustrates a cross-sectional view of an exemplary inlet nozzle of the hose-end chemical delivery system of FIG. 1; 
     FIG. 5 illustrates a cross-sectional view of an exemplary outlet nozzle of the hose-end chemical delivery system of FIG. 1; 
     FIG. 6 illustrates a side view of an exemplary output dip tube screen of the hose-end chemical delivery system of FIG. 1; and 
     FIG. 7 illustrates a top view of the dip tube screen of FIG.  6 . 
    
    
     DETAILED DESCRIPTION 
     Turning now to the figures, wherein like reference numerals refer to like elements, there is illustrated in FIG. 1 an exemplary hose-end chemical delivery system  50  comprising a cap  26  and a storage tank  24 . As will be appreciated, the storage tank  24  is adapted to contain a chemical to be sprayed, for example, a water soluble fertilizer. To sealingly secure the storage tank  24  to the cap  26 , the exterior of the storage tank  24  may be provided with threads  58  adapted to mate with threads  56  formed on the interior of the cap  26 . Additional means for securing the storage tank  24  to the cap  26 , such as providing a snap-fit connection, are also contemplated. 
     As illustrated, the chemical delivery system  50  is adapted to be connected to a source of fluid, such as water. To this end, the cap  26  may be provided with a threaded, female connector  3  that is adapted to mate with a threaded, male connector of a conventional garden hose. Preferably, the connector  3  is attached to the remaining components of the cap  26  by means of a swivel connector. A seal  2  may be provided to prevent fluid leakage from the area of any such swivel attachment. When the chemical delivery system  50  is attached to a garden hose, fluid flows in the directions indicated by the fluid flow passage  1  that is illustrated in FIG.  1 . 
     To prevent the backflow of fluid from the chemical delivery system  50  to the fluid supply, a vacuum breaker  18  may be provided within the main fluid flow passage formed in the cap  26 . In this regard, the main fluid flow passage extends between the input, illustrated as connector  3 , and an output. While not intended to be limiting, the illustrated output comprises a threaded, male connector  8  adapted to releasably mate with a spray head  27 . As will be appreciated, the vacuum breaker  18  operates in connection with a vacuum breaker exhaust  4 , formed in the cap  26  adjacent to the vacuum breaker  18 , that provides a vent to the atmosphere if a pressure reversal occurs. A seal  17  may be positioned between the vacuum breaker  18  and the interior of the main fluid flow passage to prevent leakage of fluid through the vacuum breaker exhaust  4 . 
     While not required, the cap  26  may further include a shut off valve  5 , illustrated in FIGS. 1 and 2. The shut off valve  5  allows a user to manually control the amount of fluid that is permitted to flow through the main fluid passage of the cap  26 . The shut off valve  5  may be a ball valve such as illustrated in the figures, a pistol grip lever actuated valve (e.g., like a gas pump valve), or the like without limitation. A seal  6  may be positioned adjacent to the shut off valve  5  to prevent fluid leakage. Further associated with the main fluid passage and positioned between the inlet (e.g., connector  3 ) and the outlet (e.g., connector  8 ) is a flow restrictor  7 . The flow restrictor  7  functions to restrict the amount of fluid that flows through the main fluid passage to thereby create back pressure that further functions to divert fluid into the storage tank  24  and to siphon fluid from the storage tank  24 . 
     More specifically, fluid diverted from the main fluid passage is directed to an inlet nozzle  12  that is in fluid communication with the main fluid passage. As illustrated in FIG. 1, the fluid communication between the main fluid passage and the inlet nozzle  12  is via an orifice formed in the main fluid passage on the upstream side of the flow restrictor  7 , an upper inlet nozzle  13 , and an adjustment dial  15 . The adjustment dial  15  is provided as a means for allowing a user to manually adjust the amount of fluid that is permitted to flow into the inlet nozzle  12  (i.e., to thereby control the rate of chemical mixing). To this end, the adjustment dial  15  includes a plurality of orifices  28  having various diameters (e.g., having diameters that range from approximately 0.030 to 0.060 inches) that may be selectively disposed between the upper nozzle  13  and the inlet nozzle  12 . 
     As illustrated in FIGS. 2 and 3, the plurality of orifices  28  are arranged around the adjustment dial  15  such that the orifices  28  lie on a circle concentric with the axis of the adjustment dial  15 . The orifices  28  also have a radius selected to intersect the axis of the nozzles  12  and  13 . Associated with each of the orifices  28  may be a setting indicator  25  that is visible to the user such that the user may discern which of the orifices is presently associated with the inlet nozzle  12 . 
     To allow the user to selectively associate one of the orifices  28  with the inlet nozzle  12 , the adjustment dial  15  is adapted to be rotatable. To maintain the orifices  28  in the proper orientation with respect to the nozzles  12  and  13 , the adjustment dial  15  may be provided with a detent mechanism. While not intended to be limiting, the illustrated detent mechanism is comprised of indentations  29  arranged in a concentric circle about the dial  15  that cooperate with a spring loaded pin  16  that is mounted within the cap  26 . The adjustment dial  15  may be rotated about a retaining screw  14  that is adapted to mate with an adapter plate  9  that is provided to maintain the adjustment dial  15 , inlet nozzles  12  and  13 , and an outlet nozzle  10  within the cap  26 . A seal  33  may be provided between the adjustment dial  15  and the inlet nozzle  12  to prevent fluid leakage. For the same purpose, a seal  34  may also be positioned between the inlet nozzle  12  and the adapter plate  9 . 
     As noted previously, fluid is directed from the main fluid passage to the adjustment dial  15  and, in turn, the input nozzle  12  via a top inlet nozzle  13 . Seals  31  and  32  may be used to prevent leakage of fluid from areas adjacent to this flow passage. In this regard, the dual seals  31  and  32  associated with the top inlet nozzle  13  (as well as the dual seals  33  and  34  associated with the nozzle  12 ) are especially useful to prevent leakage when the adjustment dial  15  is being rotated during those times that the system  50  is under pressure from the source of fluid. To further enhance the usefulness of the seals, it is preferred that the inlet nozzles (as well as the outlet nozzle) be designed so as to add increasingly positive pressure to the seals as pressure is increased. To this end, as illustrated in FIG. 4, the top inlet nozzle  13  may include a pressure chamber  30  and the lower inlet nozzle  12  may include a pressure chamber  34 . Optional cavities  51  and  53  may be formed in the upper inlet nozzle  12  and lower inlet nozzle  14 , respectively, to provide an additional seal when the adjustment dial  15  is being rotated while the system is under fluid pressure. 
     The pressure chamber  30  communicates with fluid in the main flow line such that flow line pressure captured in the pressure chamber  30  forces the top inlet valve to move the top inlet lower seal  32  into further engagement against the adjustment dial  15 . Similarly, the pressure chamber  34  communicates with pressure in the storage tank  24  such that storage tank pressure captured in the pressure chamber  34  forces the lower inlet valve to move the bottom inlet nozzle seal  33  against the adjustment dial. It will be appreciated that, as pressure increases in either the main flow line or the storage tank, a stronger seal is created against the adjustment dial  15 . 
     For use in mixing fluid with chemical contained within the storage tank  24 , an inlet dip tube  19 , that extends towards the bottom of the storage tank  24 , is connected to a dip tube connection  36  of the inlet nozzle  12 . As illustrated in FIG. 1, an agitation nozzle  20  is further connected to end of the inlet dip tube  19  such that fluid exiting the agitation nozzle  20  will cause chemical contained within the storage tank  24  to mix with fluid that has been delivered to the storage tank  24 . The inlet nozzle  12  also includes a fluid control port  47  that is used to layer fluid over the top of the chemical solution located at the bottom of the storage tank  24 . This manner of delivering fluid to the storage tank  24  helps to stabilize the chemical solution to create a more even injection rate. In addition, this manner of delivering fluid to the storage tank  24  helps to clear the expansion tank  24  of any dye when the chemical has been exhausted during spraying. This is particularly useful since it eliminates the situation where a user thinks chemical remain in the storage tank  24  just because the fluid remains dyed. It is to be appreciated that the control port  47  is optional. 
     To further assist in the even mixing of the chemical and the fluid, especially in the case of water soluble fertilizers, the storage tank  24  may be provided with a domed bottom into which the nozzle  20  extends. In this manner, the agitation caused by fluid exiting the nozzle  10  occurs at the bottom most portion of the storage tank  24 . Additionally, the domed bottom improves the strength of the storage tank  24  in a pressurized environment. To allow a storage tank  24  with a domed bottom to sit with stability, a ring  48  may be provided that is adapted to mate with the bottom of the storage tank  24 , for example, by being snap-fit thereto. 
     For use in venting air during filling of the storage tank  24  and for returning fluid mixed with chemical to the main fluid passage once the filling process is complete, an outlet nozzle  10 , having a mounted outlet dip tube  23 , is placed in fluid flow communication with the main fluid passage via an orifice positioned in the main fluid passage located downstream of the flow restrictor  7 . Specifically, the outlet nozzle  10 , illustrated in FIG. 5, has a first body section and a second body section that defines a fluid flow passage  40  that is in fluid communication with the main fluid passage. As seen in FIG. 1, the first body section of the outlet nozzle  10  is disposed between the main fluid passage and the adapter plate  9  and dual seals  41  and  42  may be provided to prevent fluid leakage from areas where the elements meet. The second body section of the outlet nozzle  10  extends from the adapter plate  9  towards the storage tank  24  and carries an outlet nozzle trap  11 . Preferably, the top of the outlet nozzle trap  11  engages the bottom of the adapter plate  9 . 
     The outlet nozzle trap  1  has a perforated opening  43  for accepting fluid. During the filling stage of the storage tank  24 , fluid is directed to the perforated opening  43  from a fill control port  35  formed in the inlet nozzle  12 . This fluid may then be used to inhibit the venting of air from the storage tank  24  via a vent  44  formed in the outlet nozzle  10  that is positioned within the nozzle trap  11 . The sizing of the fill control port  35  relative to the size of the outlet nozzle vent  44  will, therefore, regulate the amount of air capable of being vented via the vent  44  which, in turn, regulates the speed by which the storage tank  24  fills. As will be appreciated, controlling the fill speed in turn controls the initial injection rates, mixing, etc. Furthermore, the action between the port  35  and the port  44  helps to eliminate plugging and spurting. For example, if back pressure develops due to air resistance at the screen  21 , the system will function to automatically force more air or fluid out of port  44 . Without such a system, back pressure would develop until enough force was created to push the resisting element through the screen  21  which, when the release occurred, would cause spurting. If the resisting element were not forced through the screen, a plug would occur. 
     Once the fluid in the storage tank  24  reaches the level of the perforated opening  43  so as to be in fluid communication with the outlet nozzle vent  44 , the filling stage is complete (i.e., there no longer remains air to vent) and fluid mixed with chemical may now be siphoned into the main fluid passage from the storage tank  24  via the outlet dip tube  23  and output nozzle  10 . In this regard, fluid is drawn into the outlet dip tube  23  via a bottom outlet nozzle  22  that is attached to the bottom of the outlet dip tube  23 . Further associated with the bottom outlet nozzle  22  is a dip tube screen  21 , illustrated in FIGS. 6 and 7, having a non-clogging design. In the illustrated embodiment, the screen  21  comprises a screen meshing  46  (for example, of polypropylene) attached to vertical support rods  45 . The relationship of the vertical support rods  45  is such that the narrowest point between adjacent vertical support rods  45  is at the point where the support rods  45  engage the screen meshing  46 . In this manner, anything that is capable of passing through the support rods  45  at their outermost points of association will be able to pass through into the interior of the screen  21 . To provide a more consistent flow into the outlet dip tube  23 , it is preferred that the outlet bottom nozzle  22  extends into the middle of the screen  21 . 
     While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. For example, it is to be appreciated that various elements, such as the dip tubes, ports, etc., could be eliminated without departing from the spirit of the invention. Accordingly, the particular arrangement disclosed is meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the appended claims and any equivalents thereof.