Abstract:
A sprinkler riser having an integral water flow restrictor. The water flow restrictor is built into the riser rather than comprising a separate apparatus configured for insertion into the riser. A two component water flow restrictor allows orifice size to be adjusted to control and adjust the quantity of water permitted to pass through the riser.

Description:
CROSS REFERENCE 
       [0001]    This application is a continuation-in-part of U.S. application Ser. No. 13/571,227 filed Aug. 9, 2012 which is incorporated herein by reference for all purposes. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to a flow control device for controlling water pressure and limiting water flow to sprinkler heads in lawn sprinkler systems, and for preventing water waste from broken sprinkler heads. 
       BACKGROUND 
       [0003]    In typical lawn sprinkler systems, manifolds of water supply pipes extend beneath the surface to be watered. Sprinkler heads are spaced at intervals around a matrix of buried supply pipes, and are attached to the underground pipes through risers or stems which threadedly engage subterranean fittings and extend vertically to, or above, the surface of the ground. A plurality of heads are usually served through a single valve. 
         [0004]    Sprinkler heads may be of the fixed or pop-up variety. Pop-up sprinkler heads allow the sprinkler head to mount relatively close to the surface of the ground, elevating only when activated by water pressure resulting from actuating a valve to the system, either manually or electrically. When the water pressure is shut off, a pop-up sprinkler head will return to its resting position. 
         [0005]    A problem with lawn sprinkler systems is their inefficient use and waste of water due to excess water pressure at the sprinkler head. This excess water pressure at the sprinkler head creates a misting or atomization effect at the sprinkler head and much of this mist is lost due to evaporation or wind effects resulting in wasted water. This is especially problematic for geographic areas (e.g., Nevada) experiencing water shortages. Known prior art devices for reducing pressure or controlling water flow involve somewhat complex assemblies which are relatively expensive and may be difficult to retrofit on existing lawn sprinkler systems. 
         [0006]    Another very common problem with lawn sprinkler systems is damage to the sprinkler heads caused accidentally or by vandalism, or loss of heads to theft. Sprinkler heads are easily knocked off by pedestrian traffic, children playing on the lawn, lawn maintenance personnel and equipment, and the like. Typically, a single sprinkler valve will service a manifold having multiple sprinkler heads, frequently up to six, eight or more per line. When one sprinkler head is knocked off, water gushes from the broken line, often creating a geyser a number of feet in the air. Depending on the water pressure and the size of the line, water loss through a broken sprinkler head can be anywhere from 10-45 gallons per minute. Thus, even in a short sprinkler cycle, hundreds of gallons of water will be wasted through a broken sprinkler pipe. In addition, flow is diminished through the other sprinkler heads on the line to the point where, if the broken head is not promptly repaired, landscaping will die around the other sprinkler heads on the line. In residential settings, since lawn sprinklers may be activated by a clock for only a few minutes at a time, a broken head may not be noticed for many days, resulting in flooding and erosion in the small area where the system is broken, dying of grass in the area of adjacent sprinkler heads, and a very substantial waste of water. 
         [0007]    It would be advantageous to develop a flow restriction device capable of being retrofitted into an existing landscape sprinkler system to provide favorable pressure and flow to each sprinkler head. 
       SUMMARY 
       [0008]    Accordingly, the flow control device is sized to fit into a pop-up sprinkler inlet to reduce the cross-sectional area of the inlet thereby controlling the volume of water by restricting the flow able to pass through and inducing a pressure drop to the sprinkler head for correct droplet formation by the nozzle. In one embodiment, the flow control device is funnel-shaped or tapered with spaced ridges permitting the flow control device to “snap into” pop-up sprinkler inlets of different sizes. A top or bottom surface of the flow control device includes an opening smaller than the pop-up sprinkler inlet whereby the flow control device opening acts as the new inlet. 
         [0009]    One of the benefits of the flow control device disclosed herein is the ease with which the flow control device may be retrofitted into an installed pop-up sprinkler In general, the cover cap and stem spring assembly of the pop-up sprinkler are removed from an installed pop-up sprinkler body such that the inlet at the bottom of the body is revealed. Then, the flow control device is pressed downward through the body into the inlet until one of the ridges snaps into the inlet whereby the ridge maintains the flow control device in place against water pressure traveling through the inlet and body. Finally, the cover cap and stem spring assembly are returned to the body completing the retrofit. Given the depth of the body, an elongated tool may be used to press the flow control device into the inlet which is integrated into the bottom the body. 
         [0010]    An alternative embodiment comprises a sprinkler riser having an integral water flow restrictor. That is, the water flow restrictor is built into the riser rather than comprising a separate apparatus configured for insertion into the riser. In one such embodiment, a two component water flow restrictor allows orifice size to be adjusted to control and adjust the quantity of water permitted to pass through the riser. 
         [0011]    Other variations, embodiments and features of the present invention will become evident from the following detailed description, drawings and claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  illustrates a conventional pop-up sprinkler of the type which the embodiments of the present invention may be used; 
           [0013]      FIG. 2  illustrates a cross-sectional view of a conventional pop-up sprinkler of the type which the embodiments of the present invention may be used; 
           [0014]      FIG. 3  illustrates a perspective view of the flow control device according to the embodiments of the present invention; 
           [0015]      FIG. 4  illustrates a side view of the flow control device according to the embodiments of the present invention; 
           [0016]      FIG. 5  illustrates a top view of the flow control device according to the embodiments of the present invention; 
           [0017]      FIG. 6  illustrates a bottom view of the flow control device according to the embodiments of the present invention; 
           [0018]      FIG. 7  illustrates a cross-sectional view of the flow control device installed in a first pop-up sprinkler according to the embodiments of the present invention; 
           [0019]      FIG. 8  illustrates a cross-sectional view of the flow control device installed in a second pop-up sprinkler according to the embodiments of the present invention; 
           [0020]      FIG. 9  illustrates an exemplary tool which may be used to install the flow control device according to the embodiments of the present invention; 
           [0021]      FIG. 10  illustrates a flow chart detailing a method of installing the flow control device according to the embodiments of the present invention; 
           [0022]      FIGS. 11   a  and  11   b  illustrate an exploded perspective view and perspective view of an alternative embodiment having multiple openings according to the embodiments of the present invention; 
           [0023]      FIG. 12  illustrates a side view of a universal flow control device according to the embodiments of the present invention; 
           [0024]      FIGS. 13   a,    13   b  and  14  illustrate cut-away side views and a top view of an alternative riser with an integral water flow restrictor according to the embodiments of the present invention; 
           [0025]      FIGS. 15 and 16  illustrate top views of two components forming a first integral water flow restrictor with adjustable orifice size according to the embodiments of the present invention; and 
           [0026]      FIGS. 17 and 18  illustrate top views of two components forming a second integral water flow restrictor with adjustable orifice size according to the embodiments of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    For the purposes of promoting an understanding of the principles in accordance with the embodiments of the present invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications of the inventive feature illustrated herein, and any additional applications of the principles of the invention as illustrated herein, which would normally occur to one skilled in the relevant art and having possession of this disclosure, are to be considered within the scope of the invention claimed. 
         [0028]      FIGS. 1 and 2  show a conventional pop-up sprinkler  100  of the type with which the flow control device  200  described herein may be used. The pop-up sprinkler  100  comprises a body  105 , inlet  110 , stem  115 , spring  120 , cap  125 , wiper seal  130 , nozzle  135  and optional check valve  140 .  FIG. 1  shows the pop-up sprinkler  100  with the stem  115  in an external position relative to the body  105  such that water may be dispensed. Water traveling through the inlet  110  causes the stem  115 , via water pressure, to move to the external position. When the water stops, the spring  120  causes the stem  115  to return to an internal position within the body  105 . 
         [0029]      FIGS. 3 through 6  show various views of the flow control device  200  according to the embodiments of the present invention. The flow control device  200  is formed of a generally hollow circular body  201  defining a passageway and including a top end  205 , bottom end  210  and ridges  215  (four as shown) forming, or circumscribing, an outer surface of the body  201 . While four ridges  215 - 1  through  215 - 4  are shown, depending on the embodiment, the number of ridges may be more or less. As shown, the body  201  of the flow control device  200  tapers from narrow at the bottom end  210  to wider at the top end  205 . In other words, outermost edges  216  of each successive ridge  215  extends further outward from the bottom end  210  to the top end  205  creating the taper. With this tapered, ridged design, the flow control device  200  is able to fit into inlets of varying sizes. The flow control device  200  may also be dimensioned to fit into an elbow of an irrigation system such that it controls the flow in the same manner as described herein when inserted into the inlet  110 . 
         [0030]    A cap  220  on a top end  205  of the flow control device  200  includes an opening  225  smaller than the passageway opening at the bottom end  210  such that the opening  225  essentially becomes the new inlet for the pop-up sprinkler  100 . As shown in  FIGS. 11   a  and  11   b,  more than one opening may be incorporated as well. The flow control device  200  may be a single piece or the cap  220  may be a separate piece connected to the body  201 . The degree of flow restriction imparted by the flow control device  200  generally depends upon the size of the opening but may also depend on characteristics of the sprinkler head used, and the water pressure. The connection of the cap  220 , if separate, may be accomplished using adhesives, friction or other suitable means. The connection of the cap  220 , may also extend in a conical shape upwards and be cut different locations to create the ideal size opening. The connection of the cap  220  may also have a movable part in order to select different opening sizes to optimize the flow (see  FIGS. 11   a  and  11   b ). 
         [0031]      FIGS. 7 and 8  show cross-sectional views of a flow control device  200  installed in a first pop-up sprinkler  101  (Toro 570 and a flow control device  200  installed in a second pop-up sprinkler  102  (Rainbird 1800) according to the embodiments of the present invention. In  FIG. 7 , the flow control device  200  fits snugly into inlet  111  of the pop-up sprinkler  101  with three  215 - 1  through  215 - 3  of the four ridges  215 - 1  through  215 - 4  inserted into the inlet  111 . In  FIG. 8 , the flow control device  200  fits snugly into inlet  112  of the pop-up sprinkler  102  with two  215 - 1  through  215 - 2  of the four ridges  215 - 1  through  215 - 4  inserted into the inlet  113 . Thus, a top surface  217  of one of the ridges  215  catches an underside  114  and  116  of the inlets  111  and  112 , respectively, thereby maintaining the flow control device  200  in place. 
         [0032]      FIG. 9  shows an exemplary insertion tool  340  of the type suitable to install the flow control device  200  into the pop-up sprinkler  100 ,  101  and  102 . The tool  340  includes a number of prongs  345  which retain the top end of the flow control device  200  allowing a user to guide the second end of the flow control device through the body of the pop-up sprinkler to the inlet where the second end is inserted until the flow control device  200  snaps into place responsive to one of the ridges catching an underside of the inlet. Other tools may be used to accomplish the same objective. In another embodiment, a flow control device may be inserted into the inlet  112  from below after the pop-up sprinkler  100 ,  101  and  102  is removed from the ground and water irrigation system. That is, the inlet  112  cross-section may be reduced from below as well as from above. 
         [0033]      FIG. 10  shows a flow chart  350  detailing one method of installing the flow control device  200 . At  355 , a stem and spring are removed from a subject pop-up sprinkler At  360 , a flow control device  200  is installed by snapping into the inlet using a tool or finger if possible. At  360 , the stem and spring are returned to the pop-up sprinkler body thereby completing the retrofit. 
         [0034]      FIGS. 11   a  and  11   b  show an alternative flow control device configured to allow a user to select an opening size. As shown, four opening sizes are possible. A rotatable plate  222  includes four openings  223 - 1  through  223 - 4 . A center opening  224  rotatably joins opening  226  permitting the plate  222  to rotate (as identified by arrow A) in an offset relationship relative to a fixed cap  227  with a single opening  228  matching the size of the largest opening  223 - 4  in the rotatable plate  222 . The center opening  224  may be designed to receive a tool for rotation. With this design, the rotatable plate  222  is rotated via a raised lip  229  or the center opening  224  until a desired opening  223 - 1  through  223 - 4  aligns with the opening  228 . 
         [0035]      FIG. 12  shows a universal flow control device  300  including a first portion  305  configured to fit into many conventional sprinkler pop-ups and a second portion  315  configured to fit into a Rainbird® 1800. The first portion  305  includes 4 vertical cutouts  306  (only one visible in  FIG. 12 ) and a tapered outer wall  307  forming a lower ridge  308 . In one embodiment, the lower ridge  308  is 3.25 mm in height and has a lower edge  309  diameter of 12 mm and tapers to a 13.46 mm diameter at a top edge  310 . Above the first portion  305  is a tapered wall  316  forming an intermediary ridge  317 . In one embodiment, the distance between the top edge  310  and tapered wall  316  is 2.5 mm provided by a vertical wall  322 . Above a top edge  318  of the tapered wall  316 , a vertical wall  319  extends to an upper tapered wall  320  extending to a lip  319 . In one embodiment, the vertical wall  319  is 4.5 mm in height, the tapered wall  320  is 1.7 mm in height and the lip  319  is 1.8 mm in height while the vertical wall  319  defines a 14.25 mm diameter with the tapered wall  320  defining a diameter of 15.85 mm at a top edge thereof and an outer edge of the lip  319  defining a 16.25 mm diameter. In practice the first portion  305  fits into and is retained by the inlet of most conventional pop-up sprinklers but with the Rainbird® 1800 the first portion  305  extends through the inlet so that the wider second portion  315  inserts and is retained by the inlet thereof. In other words, the lower ridge has a smaller maximum diameter than said intermediary ridge. The dimensions are exemplary only and are determined, in this instance, to accommodate many conventional pop-up sprinklers and the Rainbird® 1800. 
         [0036]    The flow control device  200  described herein may be made of plastics, alloys, metals, composites, polymers, resins and the like and may be made using molding, rapid prototyping and machining techniques. In one embodiment, as shown in  FIG. 4 , the bottom end  210  of the flow control device  200  is 12.25 mm in diameter while the top end  205  has a diameter of 14 mm. These dimensions are exemplary and may be altered without departing from the spirit and scope of the embodiments of the current invention. 
         [0037]      FIGS. 13   a  and  13   b  show a cut-away side view and top view of a first alternative embodiment wherein a sprinkler riser  400  includes an integral water flow restrictor  405 . With such an embodiment, the riser  400  may be molded as a single unit with the water flow restrictor  405  integral with an interior portion of the riser  400 . As shown in  FIG. 13   b,  the water flow restrictor  405  is circular and defines an orifice  406  while arrow A in  FIGS. 13   a  and  14  identifies a direction of water flow.  FIG. 14  shows a water flow restrictor  408  angled towards a bottom portion  402  of the riser  400 ′. The angled water flow restrictor  408  may also be angled towards a top portion  401 . The water flow restrictor  405 ,  408  can be integrated at any location within the riser  400 ,  400 ′. For example, the water flow restrictor  405 ,  408  may be integrated proximate a top, middle or bottom of the riser  400 ,  400 ′. The water flow restrictor  405 ,  408  may also take on varied thicknesses, dimensions, shapes and may be angled or flat. The orifice  406 ,  410  or orifices, as shown, may be centered or off center (not shown) and may take on variable sizes. Other than molding, the sprinkler riser  400 ,  400 ′ may be fabricated with the integral water flow restrictor  405 ,  408  using machining and rapid prototyping and may be fabricated of any suitable materials, including, but not limited to, plastics, alloys, composites, resins and metals. In another embodiment, the water flow restrictor  405 ,  408  may include one or more scored or otherwise weakened areas which a user may poke out with a tool creating one or more additional orifices thereby increasing water flow through the forward part of the riser as desired. 
         [0038]      FIGS. 15 and 16  show two components of an alternative integral water flow restrictor which provides adjustability of the size of an offset orifice.  FIG. 15  shows an upper stationary disc  460  and  FIG. 16  shows lower movable disc  465 . The upper stationary disc  460  is molded or otherwise integral with a subject riser. The stationary disc  460  includes a center connection point  470  and first offset orifice  475 . The lower movable disc  465  includes a central connection point  480  and second offset orifice  485 . In practice, the lower movable disc  465  may be rotated relative to the stationary disc  460  such that the second offset orifice  485  may be aligned with all or a portion of the first offset orifice  475  to increase the total passageway area for water. Teeth  490  along an outer perimeter of the lower movable disc  465  frictionally interact with an interior surface of the riser to maintain the lower movable disc  465  in position once adjusted. The central connection points  470  and  480  receive a screw, rivet or similar mechanism connecting the stationary disc  460  and movable disc  465  to one another while allowing the movable disc  465  to rotate relative to the stationary disc  460 . Those skilled in the art will recognize that the upper stationary disc  460  may be made movable and the lower movable disc  465  may be made stationary. 
         [0039]      FIGS. 17 and 18  show two components of an alternative integral water flow restrictor which provides adjustability of the size of an offset orifice.  FIG. 17  shows an upper stationary disc  505  and  FIG. 16  shows lower movable disc  510 . The upper stationary disc  505  is molded or otherwise integral with a subject riser. The stationary disc  505  includes a central connection point  515  and multiple orifices  520 - 1  through  520 -N of the same or varied sizes. The lower movable disc  510  includes a central connection point  525  and offset orifice  530 . In practice, the lower movable disc  510  may be rotated relative to the stationary disc  505  such that the offset orifice  530  may be aligned with one or more of the orifices  520 - 1  through  520 -N to increase the total passageway area for water. Teeth  535  along an outer perimeter of the lower movable disc  510  frictionally interact with an interior surface of the riser to maintain the lower movable disc  510  in position once adjusted. The central connection points  515  and  525  receive a screw, rivet or similar mechanism connecting the stationary disc  505  and movable disc  510  to one another while allowing the movable disc  510  to rotate relative to the stationary disc  505 . Those skilled in the art will recognize that the upper stationary disc  505  may be made movable and lower movable disc  510  may be made stationary and the offset orifice  530  and one or more orifices  520 - 1  through  520 -N may be switched to the other disc such that the offset orifice  530  is stationary and the one or more orifices  520 - 1  through  520 -N are movable. 
         [0040]    Movement of the movable discs  465 ,  510  may be accomplished with one&#39;s fingers or a slender tool able to reach into the riser. 
         [0041]    Although the invention has been described in detail with reference to several embodiments, additional variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims.