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CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    None 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not Applicable 
       REFERENCE TO A MICROFICHE APPENDIX 
       [0003]    Not applicable 
       BACKGROUND 
       [0004]    The invention generally relates to an apparatus used for swimming pool water filter and recirculation circuits. More specifically, the invention relates to mounting a shield on the entrance of a pool skimmer to prevent debris from entering the skimmer and clogging flow through the pool filter. Further, the invention relates to a skimmer shield that can be selectively opened and closed without demounting the shield. 
         [0005]    Swimming pools and hot tubs utilize fluid recirculation circuits to filter and regulate chemical balance in the water. Typically, water enters the circuit through a skimmer located in the side of the pool. Once in the skimmer, water flows through a filter and then to the suction of a recirculation pump. The pump typically returns the water to the pool through jets. 
         [0006]    A variety of sizes and shapes of skimmers are available for new pool construction and are in use in existing pools. The skimmer pool water opening is typically rectangular and is located in the side of the pool at the normal water level in the pool. Some simmers have floating weir-type doors. Skimmer filters typically consist of a hidden removable basket which must be emptied of leaves, twigs, animals, insects and other debris. If the filter becomes clogged, flow through the filter is blocked resulting in potential damage to the recirculation pump. Accordingly, the filter must be monitored to prevent costly damage to the recirculation system. 
         [0007]    Debris collecting in the filter can vary with the seasons of the year. For example, deciduous trees and bushes tend to shed leaves and seed pods on a seasonal basis. Winds depositing debris in the pool can be seasonal. During portions of the year, the filter must be examined and emptied daily. Accordingly, the need and effectiveness of skimmer shields is seasonal. During these periods, absent pool owners must either turn off the recirculation pump or utilize skimmer shields to prevent debris from entering the skimmer filter system. Skimmer shields typically consist of screens or other flow-through devices mounted at the skimmer opening that block debris from entering the skimmer. Installation and operation of existing skimmer shields are undesirable. 
         [0008]    For example, prior art skimmer shields proposed to block debris from entering the skimmer include U.S. Pat. No. 4,140,634 to Harry which discloses a removable shield which attaches to the pool by threading bolts into the side of the pool or using suction cups. Drilling holes into the side of pool or face of the skimmer is not recommended, and suction cups can fail leaving the skimmer unprotected. 
         [0009]    In U.S. Pat. No. 5,935,450 to Benedict, a screen type shield is mounted with retention flanges extending into the sides of the skimmer. This is an example of a skimmer mounting configuration that must be designed to fit a particular size skimmer. This device is quite unattractive and can and must me removed when not needed. 
         [0010]    U.S. Pat. No. 5,937,453 to Hodak, et al. discloses a skimmer shield whose mounting configuration requires a specially described skimmer face plate to mate with the skimmer shield. Like the Benedict patent this configuration requires a different design for each different skimmer shape. 
         [0011]    In U.S. Pat. No. 6,770,193 to Foley, the skimmer screen has a rectangular portion designed to fit into a particular shaped skimmer opening. 
         [0012]    The skimmer shield in U.S. Pat. No. 6,989,094 to Knapp, et al. uses magnetic disks glued to the pool side to mount a removable screen filter. 
         [0013]    The removable skimmer closure device in the U.S. Pat. No. 6,578,208 to Bruce mounts using undesirable screws threaded into the face plate of a skimmer. 
         [0014]    The skimmer guard of U.S. Pat. No. 6,817,041 to Evans, et al. is size dependent and uses spring loaded tabs to fit into the opening of a skimmer. 
         [0015]    Snap hooks spaced to fit in the skimmer opening are used to mount a skimmer guard in U.S. Pat. No. 7,052,602 to Boggs, et al. 
         [0016]    Therefore, it is desirable to provide a shield that can be mounted in a variety of sizes and shapes of skimmers and can be used as needed. 
       SUMMARY OF THE INVENTION 
       [0017]    In one embodiment, the invention provides a shield that can be mounted in a variety of shapes and sizes of pool skimmers. 
         [0018]    In another embodiment of the present invention, the skimmer shield, once installed, can be selectively changed to block or permit debris to enter the skimmer and filter therein. 
         [0019]    In a further embodiment of the present invention the skimmer shield has a closure means that can be opened and closed to permit or block debris from entering the skimmer. 
         [0020]    In one embodiment, the invention uses sliding perforated doors to selectively prevent debris from entering the skimmer with the pool water. 
         [0021]    These and other aspects of the invention will be apparent to one skilled in the art upon reading the following detailed description. While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof will be described in detail and shown by way of example. It should be understood, however, that it is not intended to limit the invention to the particular forms disclosed, but, on the contrary, the invention is to cover all modifications and alternatives falling within the spirit and scope of the invention as expressed in the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]      FIG. 1  is a perspective view of a skimmer shield according to the present invention; 
           [0023]      FIG. 2A  is a front elevation view to the skimmer shield of  FIG. 1  with the closure member shown in the closed position; 
           [0024]      FIG. 2B  is a front elevation view of the skimmer shield of  FIG. 1  with the closure member shown in the open position; 
           [0025]      FIG. 3  is a left side elevation view of the skimmer shield of  FIG. 1 ; 
           [0026]      FIG. 4  is a section view of the skimmer shield of  FIG. 2A  taken on line  4 - 4  looking in the direction of the arrows; and 
           [0027]      FIG. 5  is a top plan view of the skimmer shield of  FIG. 1 , with the closure member shown in the closed position. 
       
    
    
     DETAILED DESCRIPTION 
       [0028]    Referring now to the figures wherein reference numerals are used to refer to like or corresponding parts through the several views, there is shown in  FIGS. 1-5  one example embodiment of the present invention. In these FIGURES, a skimmer shield assembly referenced generally by reference numeral  10  is illustrated for use as an attachment to a pool skimmer. In  FIG. 1 , an example skimmer opening  14  is shown in phantom lines with the skimmer spaced away from it before mounting. The skimmer opening  14  is also illustrated in phantom lines in  FIGS. 4 and 5 . 
         [0029]    For ascetic purposes, the shield  10  is constructed from clear or transparent material, preferably a plastic material. In this embodiment, the shield  10  comprises a body  20  having a generally planar central portion  22 . In the illustrated embodiment, portion  22  is generally rectangular and is selected to be of a size to accommodate and cover the pool opening  14  on commonly-available skimmers. 
         [0030]    As viewed in the FIGURES, portion  22  has upper and lower flanges  24  and  26 , respectively. In the illustrated embodiment, flanges  24  and  26  are for ease in fabrication integrally formed with the portion  22  and extend transverse thereto. Flanges are generally trapezoid shaped narrowing in the top plan view away from the portion  22 . 
         [0031]    Left and right side flanges  28  also extend from the portion  22 . For ease of fabrication, these flanges  28  are integrally formed front portion  22 . As shown in  FIG. 5 , these flanges  28  are not parallel to portion  22  and extend rearward about 5 degrees to 25 degrees, preferably 15 degrees. Portion  22  and flanges  26  and  28  have a plurality of openings  30  formed therethrough to permit pool water to flow therethrough. Openings  30  are selected to be of a size to permit flow of pool water from the pool into the skimmer opening. Openings  30  are small enough to prevent most debris from passing therethrough. Openings  30  are illustrated as simple drilled holes, however, slots or other shapes could be used. Alternatively, larger openings could be provided covered by a screening material or the like to eliminate debris passage. 
         [0032]    As is illustrated, a passageway  32  large enough to permit most debris to flow therethrough (larger than the openings  30 ) is formed in the portion  22 . In the illustrated embodiment, the passageway  32  is generally rectangular to correspond to the shape of most skimmer openings. The passageway is selected to have a cross-sectional area at least about 25 percent of the cross-sectional area of the skimmer opening and can have a cross-sectional area larger than the skimmer opening. The passageway  32  is centrally located so that, when the shield  10  is installed, it will align with a portion of the skimmer opening  14 . In the illustrated embodiment, passageway  32  is equipped with closure member that can be selectively opened or closed. In the closed position illustrated in  FIG. 2A , debris in the pool water is prevented from entering the skimmer opening with the pool water. In the open position illustrated in  FIG. 2B , pool water and debris flows through the opening  32  and into the skimmer filter. 
         [0033]    In the illustrated embodiment, the closure member comprises a pair of sliding flow-through door-like structures  40 . Structures  40  are mounted in upper and lower opposed U-shaped tracts  42  and  44 , respectively. Openings  46  are formed in structures  40  to flow pool water therethrough when in the closed position (see  FIG. 2A ). Stops  48  are formed on the inside of the structures to limit movement and to maintain the structures  40  in the tracks  42  and  44 . While the sliding configuration has benefits, it is envisioned the pivots or even removal structures could be used in place of the sliding configuration shown. 
         [0034]    As is illustrated in  FIG. 3 , a retaining device  50  is mounted in the upper flange  24 . In the disclosed embodiment, device  50  comprises a bolt and a pair of nuts extending through a bore in the flange  24 . The retaining device  50 , when extended into contact with the upper wall  52  of the skimmer opening, functions to hold shield assembly  10  in place. 
         [0035]    Device  50 , of course, could be located in the bottom flange  26  and press the upper flange against wall  52 . Indeed, more than one device  50  could be used, one in each flange or multiples in one or more flanges. In the present embodiment, the flanges  24  and  26  extend from the portion  22  and act as springs to hold the shield in place. It is also envisioned that the device  50  could be in the form of a compressible member or the like such as a leaf or coil spring mounted on one of the flanges. In another embodiment, the device  50  could be in the form of a spreader forcing or deflecting the flanges  24  and  26  outward into contact with the walls of the skimmer opening. 
         [0036]    If multiple devices  50  are used with at lease one in each of the upper and lower flanges, the relative height of the mounted shield can be adjusted to a particular pool water level. This allows the shield to be installed at an ideal operating height in a variety of skimmer sizes. 
         [0037]    To install and use the skimmer shield  10 , upper and lower trapezoid shaped tapered flanges  24  and  26  are inserted into the skimmer opening  14  until the side flanges  28  contact the pool wall  60  as shown in  FIGS. 4 and 5 . The taper of flanges  24  and  26  permits the skimmer shield to be mounted in a variety of widths. Typically, the pool water level intersects the skimmer opening to collect (or skim) floating debris in the skimmer filter. 
         [0038]    According to a feature of the present invention, contact between side flanges  28  and the pool side wall position the portion  22  in a spaced-away relationship with pool wall. This mounting configuration allows the openings  30 , located below the water surface in the lower flange  26 , to come into use when floating debris collected on the shield restricts flow through openings at water level. 
         [0039]    The closure structure  40  is opened gaining access to the mounting bolt and nut assembly  50 . The bolt is extended to contact the upper wall of the skimmer opening  14  (as shown) and is set in place by tightening the nuts. Once installed, the shield can be opened and closed as desired. When needed, such as when the pool owner is out of town, the shield can be closed to prevent the accumulation of debris in the skimmer filter and resulting damage to the pump. When not required, the shield closure is left open allowing the debris to accumulate in the filter and be removed as required. 
         [0040]    The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims and their equivalents appended hereto.

Summary:
The invention provides a shield for attachment to a swimming pool skimmer to prevent debris in the pool water from entering the skimmer. The skimmer shield has a closure member in the form of a door that can be opened or closed to allow unrestricted flow into the skimmer when necessary. The shield mounts in the skimmer opening using a pair of tapered flanges and releasable lock in the form of a screw.