Patent Abstract:
A barrier device ( 1 ) and technique for use in the plumbing during construction of a swimming pool includes a tubular cylindrical section ( 2 ) having an open first end. A pop-out barrier ( 12 ) is integral with the cylindrical section, and is disposed to cover a second end of the cylindrical section. In one embodiment, an annular water barrier flange ( 3 ) is integral with the cylindrical section, and is disposed about a mid portion of the cylindrical section to prevent water leakage around an outer surface of the cylindrical section ( 2 ) when the barrier device is installed on the end of a water return pipe or drain pipe extending through the a wall surface of a swimming pool.

Full Description:
BACKGROUND OF THE INVENTION  
         [0001]    This application claims the benefit of prior filed co-pending U.S. provisional application Serial No. 60/334,049 filed Nov. 28, 2001 entitled “SWIMMING POOL LEAK STOP PLUMBING ADAPTER AND METHOD” by William C. Tarr.  
           [0002]    The invention relates to improvements in the plumbing part of the construction of swimming pools. More particularly, the invention relates to a barrier device and method which (1) prevents leakage of pool water around plumbing, such as return pipes, extending through the gunite (i.e., shotcrete) layer of the wall of the partially constructed swimming pool or drain pipes extending through the gunite layer for connection to drain fixtures, and (2) also prevents leakage of plaster or other interior surface finishing material into open ends of any exposed plumbing extending through the gunite layer as the plaster or other finishing material is applied thereto.  
           [0003]    A problem of the prior art is that the above described application of plaster or other interior surface finishing material results in leakage of some of the material into the open ends of the return water pipes or drain pipes as the material is being applied. The presence of plaster or the like in the open ends of the water return pipes or drain pipes may cause considerable difficulty, especially if slurry or plaster material hardens before being removed from the pipes.  
           [0004]    In the past, pool construction workers have sometimes applied tape over, or inserted sponges into, the open ends of the return water pipes or drain pipes extending through and beyond the gunite layer of which the swimming pool wall and floor are constructed. However, that approach has been inadequate, because some of the plaster or slurry inevitably passes through the tape or sponge into the open end of the water return pipes and/or drain pipes.  
           [0005]    Another problem of the prior art is that after the swimming pool construction has been completed and the pool has been filled with water, leakage of pool water occurs around the outside surfaces of the return water pipes and drain pipes through defective seals between the water pipes and the pool wall, because of the failure of pool wall materials to provide a reliable seal with the outside surfaces of the pipes. When gunite is applied to the interior of the pool, the nozzle usually is positioned higher than plumbing pipes that pass through the pool “shell” or wall. This often leaves a void underneath a protruding pipe. Also, the gunite material being applied can slump and create voids around plumbing that passes through the pool wall. Such voids can cause leakage of pool water if a good seal is not provided around the pipe during application of the interior surface plaster or other finish. Also, during temperature changes from summer to winter in warmer climates, the gunite and interior finish expands and contracts. This causes leakage of pool water around plumbing pipes that pass through the gunite structure. Such leakage can cause soil expansion problems and cracking of the swimming pool wall. Repairing such a defective seal after the pool has been completed can be very expensive, especially if the surrounding portion of the pool bottom or pool wall needs to be removed by means of a jackhammer and replaced by new wall material.  
           [0006]    U.S. Pat. No. 4,951,326 (Barnes et al.) discloses several “eyeball” fittings which can be provided in the floor and wall of the swimming pool or spa during construction. The “eyeball” fittings are relatively high-precision, expensive fittings, and their pivoting operation would be impaired by plaster debris introduced into the fittings during plastering of the pool or spa. To avoid this difficulty, the “eyeball” fittings have caps which prevent plaster or other finish from entering the fittings as the finish is applied. In one embodiment, a breakaway cap  30  is integral with a threaded retaining ring that retains a spherical eyeball member in the fitting. After the finishing operation, the retaining ring is threaded further into the fitting, causing pressure of the fitting on the periphery of the cap to break it away from the retaining ring. In another embodiment disclosed in U.S. Pat. No. 4,951,326, a disk-shaped breakaway cap  50  is attached by a frangible web  54  and a pair of dielectrically opposed tabs  61  to an open mouth of the fitting. The tabs  61  act as pivot points when a peripheral point of the breakaway cap is hit with a hammer, causing it to tilt so it can be grasped and removed by breaking the tabs. The device is costly because it requires several separate molded parts. In a third embodiment, a breakaway cap  70  includes hook-like projections that hold the breakaway cap  70  in place during plastering or other finishing by extending into and engaging the socket within which the “eyeball” element is retained. After plastering, a screwdriver is forced through a weak spot  74  in the breakaway cap  70  and tilted so as to disengage the book-like projections and remove the breakaway cap. The devices disclosed in U.S. Pat. No. 4,951,326 are intended to be used as restricted wall return fittings for the purpose of controlling the direction of pool water being returned into the pool.  
           [0007]    U.S. Pat. No. 4,063,759 (Steimle) discloses a water barrier device including the tubular sleeve encircled by flanges having a fluid-tight seal with the exterior of the pipe extending through the wall of the swimming pool. The device must be slipped over the outside portion of pool plumbing in order to be embedded into the gunite or pool finish. Therefore, it is necessary to clean a relatively large surface area of the end of the pipe before the tubular sleeve can be slid over the end of pipe and cemented thereto. However, pool finish contractors usually will not use this type of fitting because the cleaning of the pipes required before installing this type of water barrier is far too time consuming.  
           [0008]    It would be desirable to provide a practical device and technique to prevent leakage of water in a swimming pool around return water pipes and drain pipes extending through the walls of swimming pools and simultaneously provide a convenient, inexpensive way of preventing plaster or other interior surface finishing material from leaking into the open ends of return water pipes and drain pipes while plaster or other interior surface material is being applied onto the gunite layers of partially constructed swimming pools.  
         SUMMARY OF THE INVENTION  
         [0009]    It is an object of the invention to provide a barrier device and technique for making improved plumbing connections along the interior surface of a swimming pool to avoid leakage of pool water around plumbing connections through the pool wall.  
           [0010]    It is another object of the invention to provide a barrier device and technique to prevent plaster or other interior pool finishing material from entering open ends of plumbing connections such as water return pipes or drain pipes extending through the gunite wall layer of a partially constructed swimming pool during application of plaster or other interior pool surface material to the gunite layer.  
           [0011]    It is another object of the invention to provide a single device that effectively functions as both a barrier device for making improved plumbing connections along the interior surface of a swimming pool to avoid leakage of pool water around plumbing connections through the pool wall and as a barrier device to prevent plaster or other interior pool finishing material from entering open ends of plumbing connections such as water return pipes or drain pipes extending through the gunite wall layer of a partially constructed swimming pool during application of plaster or other interior pool surface material to the gunite layer.  
           [0012]    Briefly described, and in accordance with one embodiment thereof, the invention provides a barrier device and technique for use in the plumbing during construction of a swimming pool. The barrier device ( 1 ) includes a tubular cylindrical section ( 2 ) having an open first end. A pop-out barrier ( 12 ) is integral with the cylindrical section, at a second end portion of the cylindrical section, and is disposed to cover the second end portion of the cylindrical section. In the described embodiment, an annular water barrier flange ( 3 ) is integral with the cylindrical section, and is disposed about a mid portion of the cylindrical section to prevent water leakage around the outer surface of the cylindrical section ( 2 ) when the barrier device is installed on the end of a water return pipe or a drain pipe extending through the wall surface of a swimming pool. The pop-out barrier includes a thin annular section ( 12 A) peripherally connected by a thinned or scored first web ( 15 ) and a thickened hinge portion ( 15 A) of the first web to an edge portion of the second end. The pop-out barrier also includes an inner section ( 12 B) peripherally connected by a end second web ( 17 ) and a thickened hinge portion ( 17 A) of the second web to an inner edge portion of the annular section ( 12 A). In the described embodiment, a barrier device is a debris/water barrier device, wherein an integral annular water barrier flange ( 3 ) is disposed about a mid portion of the cylindrical section to prevent water leakage around an outer surface of the cylindrical section ( 2 ) when the device is installed on an open end of the water return pipe or drain pipe. The annular water barrier flange includes an outer surface ( 3 B) and a peripheral lip ( 3 A) extending outward from the outer surface.  
           [0013]    Construction of the swimming pool includes applying gunite material to form a wall and a floor of the swimming pool so that open end portions of a plurality of water return pipes extend beyond a surface of the gunite material. A debris/water barrier device or the like is attached to each extending open end portion, respectively. A layer of interior finish material is applied to the gunite so that the interior finish material is flush or nearly flush with the pop-out barrier ( 12 ). The inner section ( 12 B) is struck so as to break part of the second web ( 17 ) so that the inner section ( 12 B) hangs inside a volume bounded by the pop-out barrier ( 12 ). A retracting element is inserted into a resulting hole in the annular section, and the annular section ( 12 A) is pulled outward so as to break the first web ( 15 ) in removing the pop-out barrier ( 12 ).  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    [0014]FIG. 1A is a perspective view of a debris/water barrier device for plumbing swimming pools.  
         [0015]    [0015]FIG. 1B is a partial perspective cutaway view of the debris/water barrier device of FIG. 1A.  
         [0016]    [0016]FIG. 2 is a partial perspective view illustrating a water return pipe or drain pipe extending through the gunite wall of a partially constructed swimming pool.  
         [0017]    [0017]FIG. 3 is a partial perspective cutaway section view illustrating installation of the debris/water barrier device of FIGS. 1A and 1B on an open end of the pipe in FIG. 2 extending through the inner surface of a gunite layer of a partially constructed swimming pool.  
         [0018]    [0018]FIG. 4 is a partial perspective cutaway section view illustrating the structure of FIG. 2 after application of a layer of plaster surfacing on the gunite layer.  
         [0019]    [0019]FIG. 5 is a partial perspective cutaway section view illustrating removal of the center popout barrier of the debris/water barrier device of FIGS. 1A and 1B.  
         [0020]    [0020]FIG. 6 is a partial perspective cutaway section view illustrating removal of the outer popout barrier from the debris/water barrier device.  
         [0021]    [0021]FIG. 7 is a partial perspective cutaway section view illustrating an alternative installation of the debris/water barrier device of FIGS. 1A and 1B on an open end of the pipe in FIG. 2 extending through the inner surface of a gunite layer of a partially constructed swimming pool.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]    Referring to FIGS. 1A and 1B, debris/water barrier device  1  of the present invention includes a hollow, open-bottom cylindrical section  2  having a 1.5 inch inside diameter into which a standard 1.5 inch PVC schedule  40  pipe can be inserted. Cylindrical section  2  includes a lower section  2 A and an upper section  2 B having the same inside diameter as lower section  2  and a larger outside diameter than lower section  2 A. The lower section  2 A has an outside diameter which is tapered from 2.015 inches at its bottom edge to 2.050 inches at its upper portion. This allows lower section  2 A to be snugly inserted into and cemented within an open end of a standard 2 inch schedule 40 PVC pipe  20  despite variations in the inside diameter thereof, if 2 inch PVC pipe rather than 1.5 inch PVC pipe is used. In a prototype device, the length of cylindrical section  2  (including both sections  2 A and  2 B) is ⅜ inches. This also allows the fitting to be installed precisely perpendicular to the finished interior pool surface.  
         [0023]    The top end  10  of cylindrical section  2  is covered by an integral thin, disk-shaped pop-out barrier  12  which preferably is integral with cylindrical section  2 . Reference numeral  15  indicates a thin cut or thin web around the periphery of pop-out barrier  12  which allows it to be easily popped out from cylindrical section  2 , and reference numeral  15 A designates a thickened “hinge” portion of web  2  to more firmly connect pop-out barrier  12  to the inside of upper section  2 B of cylindrical section  2  when the rest of barrier  12  is popped out. Pop-out barrier  12  includes an annular pop-out section  12 A the periphery of which is connected by thin web  15  directly to upper section  2 B of cylindrical section  2 , and also includes a central circular (or other shape) pop-in barrier  12 B which can be popped inward relative to annular pop-out section  12 A, to allow a hook, finger or the like to be inserted through the resulting hole in order to pull out annular popout section  12 A. Reference numeral  17  indicates a thin cut or thin web around the periphery of central pop-in barrier  12 B which allows pop-in barrier  12 B to be easily popped inward, and reference numeral  17 A designates a thickened “hinge” portion of web  17  to more firmly connect central pop-in barrier  12 B to the inside of upper section  2 B of cylindrical section  2  when the rest of barrier numeral  12 B is popped in. This prevents pop-out section  12  from falling downward into the pipe  20  (FIG. 3) on which debris/water barrier device  1  is installed and therefore avoids the difficulty of retrieving a pop-in barrier  12 B that has fallen into the pipe.  
         [0024]    An annular water barrier flange  3  is attached to and surrounds the mid section of cylindrical section  2 . The diameter of water barrier flange  3  can be 3 inches. Water barrier flange  3  has a raised peripheral lip  3 A which rises ⅛ of an inch above a flat annular upper surface  3 B of water barrier flange  3  as shown in FIG. 1A. The purpose of water barrier flange  3  is to provide a high-integrity seal with the plaster or other interior surface material which is applied to the gunite layer.  
         [0025]    Preferably, debris/water barrier device  2  is a completely integral unit formed of ABS plastic, although other suitable plastic material such as PVC (polyvinyl chloride) or CPVC can be used.  
         [0026]    Referring to FIG. 2, reference numeral  20  designates either the open end section of a drain pipe or the open end of a swimming pool water return pipe coupled to the low pressure side of a pool pump (or the open end of a return pipe extending through the pool wall and coupled to the high pressure side of the pool pump). The open end of pipe  20  extends above or beyond a gunite layer  22  lining the walls and bottom of a hole that has been excavated for construction of the swimming pool. Typically, if pipe section  20  is 1.5 inch PVC pipe, its outer end extends so that it will be flush with the layer of plaster or other finish subsequently applied to gunite layer  22 , and if the pipe section  20  is 2 inch PVC pipe, its outer end extends so that it is approximately ⅝ inches behind the layer of plaster or other finish subsequently applied to the inner surface of gunite layer  22 .  
         [0027]    Normally, the next stage in construction of the pool is to apply a layer of plaster or other pool interior surface material onto the gunite layer surface  22 A. (As previously mentioned, in the past workers sometimes have placed duct tape or sponge over or into the open end of pipe  20  to prevent the plaster or other pool interior surface material from leaking into the pipe  20 .) However, in accordance with the present invention, an end portion of pipe  20  is cleaned to remove gunite debris or other debris there from. For 1.5 inch PVC pipe, the end portion to be cleaned typically is 1 to 3 inches long. Then debris/water barrier device  1  is installed on the open end of pipe  20 , above the gunite surface  22 A as shown in FIG. 3. (If pipe  20  is a water return pipe, then it may extend horizontally beyond, rather than vertically above, the gunite surface.) Depending on whether pipe  20  is 1.5 inch or 2 inch schedule  40  PVC pipe, it can either be slid into the inside passage extending through debris/water barrier device  1  or it can be slid over the slightly tapered outer surface of lower section  2 A as shown in FIG. 7. In either case the joint can be cemented by means of ordinary PVC cement. If pipe  20  is 1.5 inch Schedule  40  PVC pipe, it can be slid entirely through debris/water barrier device  1  if barrier  12  is popped out, so that the outer end of pipe  20  extends beyond the edge  10 . Then a threaded PVC adapter can be cemented to the protruding outer end portion of pipe  20  to facilitate mounting a fixture thereon.  
         [0028]    Referring to FIG. 4, the next step in the pool construction process is to apply a layer  26  of plaster (or other interior pool surface material) on the gunite surface  22 A, so that the outer surface  26 A of the plaster layer is flush with the top of debris/water barrier device  1 . During this process, pop-out barrier  12  prevents any of the plaster (or other interior pool surface material) from entering the open end of pipe  20 . During application of the plaster  26 , the pop-out barrier  12  prevents any plaster (or other interior pool surface material) from entering the open end of pipe  20 , and the annular water barrier flange  3  provides a high-integrity seal with the plaster or other pool interior surface material.  
         [0029]    Removal of pop-out barrier  12  needs to be done in such a manner that it does not fall into pipe  20 . This will not happen if pipe  20  is 1.5 inch schedule  40  PVC pipe as illustrated in FIGS.  2 - 6 , because the diameter of pop-out barrier  12  is greater than the inside diameter of 1.5 inch schedule  40  PVC pipe. However, if pipe  20  is 2 inch schedule  40  PVC pipe and therefore is fit over the outer surface of lower section  2 A of debris/water barrier device  1 , then pop-out barrier  12  may fall into pipe  20  and cause the above mentioned retrieval problem.  
         [0030]    To avoid this problem, pop-out barrier  12  can be removed by a two-step process as shown in FIGS. 5 and 6. First, the small, center pop-in barrier  12 B can be popped inward or downward as shown in FIG. 5. The thickened hinge portion  17 A shown in FIGS. 1A and 1B will cause center pop-in barrier  12 B to hang downward as illustrated.  
         [0031]    Then, as shown in FIG. 6, a screwdriver or the like can be inserted through the center opening left by the removal of center pop-in barrier  12 B and wielded to pop barrier  12 A outward.  
         [0032]    The thickened hinge portion  15  (FIG. 1A) retains pop-out barrier  12  in the configuration shown in FIG. 6. Pop-out barrier  12  then can be easily pulled loose and discarded. Then, if desired, a conventional fitting can be installed on or in the open end of debris/water barrier device  1 .  
         [0033]    The above described debris/water barrier device and method of installation avoids the need to use the above mentioned ineffective duct tape to prevent the leakage of plaster or the like into the open end of return water pipes or drain pipes during the interior pool surface application process. The above described debris/water barrier device and method also prevent undesired leakage of pool water along the outer surfaces of water return pipes and drain pipes, because the annular water barrier flange  3  provides more surface area for the plaster (or other interior pool surface material) to seal with. The provision of the raised lip  3 A allows the plaster  26  to readily fill the recess defined by raised lip  3 A, bottom surface  3 B and the wall of upper section  2 B, and thereby provides increased structural rigidity of the interface between the plaster  26  and the annular flange  3 , which ensures a good seal despite the presence of voids and/or slight distortions of the gunite wall or pipe  20  which weaken the seal, for example, due to thermal gradients and differences in the thermal coefficients, stresses due to the shifting of the earth, etc. The bottom surface of annular flange  3  is flat in order to avoid formation of any void spaces underneath the flange  3  as the plaster  26  flows underneath flange  3 . (Any such voids would reduce the structural integrity of the interface between water barrier flange  3  and the gunite and therefore would reduce the long-tenn reliability of the seal between them.) The increased structural rigidity is desirable to prevent the seal between the plaster and stop leak device  1  from being weakened or disrupted by stress at the interface between plaster layer  26  and gunite layer  22  caused by the different coefficients of expansion of plaster layer  26  and gunite layer  22 . The need to clean a 2 to 3 inch section of pipe  20  as would be necessary for use of the barrier device disclosed in above mentioned U.S. Pat. No. 4,063,759 is avoided. The ability of the described debris/water barrier device  1  to be mounted in either 1.5 inch or 2 inch Schedule  40  PVC pipe avoids the cost of manufacturing and stocking two different sizes thereof.  
         [0034]    While the invention has been described with reference to several particular embodiments thereof, those skilled in the art will be able to make the various modifications to the described embodiments of the invention without departing from the true spirit and scope of the invention. It is intended that all elements or steps which are insubstantially different or perform substantially the same function in substantially the same way to achieve the same result as what is claimed are within the scope of the invention. For example, pop-out barrier  12  could be slightly recessed into the top end  10  of debris/barrier device  1 .

Technology Classification (CPC): 5