Patent Publication Number: US-6654972-B1

Title: Water recreational apparatus with rotating filter doors

Description:
FIELD OF THE INVENTION 
     This invention relates generally to water recreational apparatuses, and more specifically, to water recreational apparatuses having a filtering system. 
     BACKGROUND OF THE INVENTION 
     Water recreational apparatuses, such as portable spas, hot tubs, above ground pools and water recirculating bath tubs have become very popular. Many such water recreational apparatuses have water filters wherein a portion of the water within the basin is withdrawn via a filter opening, filtered to remove suspended debris and reintroduced into the water basin. 
     In conventional water recreational apparatuses of the prior art, the filter opening is typically a spill way defined in the uppermost portion of one of the side walls of the apparatus. The problem with this spill way configuration is that the only water in the apparatus that is filtered is water at the very upper level in the apparatus. Also, the spill way configuration takes up space and does nothing to add to the overall aesthetic appearance of the apparatus. 
     Accordingly, there is a need for a water recreational apparatus which overcomes these problems in the prior art. 
     SUMMARY OF THE INVENTION 
     The invention satisfies this need. The invention is a water recreational apparatus comprising (a) a water basin having side walls and a bottom wall, (b) a filter disposed external of the basin, (c) a pump having a suction side and a discharge side, (d) suction side water circulation lines serially connecting the water basin, the filter and the suction side of the pump, and (e) discharge side water circulation lines connecting the discharge side of the pump and the water basin. In the invention, the side walls comprise one or more side wall doors to allow the flow of water from the water basin to the suction side water circulation lines, the one or more side walls being movably affixed to the basin so that they can move between a closed position and an open position. Also in the invention, the water circulation apparatus further comprises biasing means to bias the one or more side wall doors to the closed position when the pump is not operating, but allowing the one or more side wall doors to move toward the open position when the pump is operating. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     These and other features, aspects and advantages of the present invention will become better understood with reference to the following description, appended claims and accompanying drawings where: 
     FIG. 1 is a diagrammatic side view of a water recreational apparatus having features of the invention; 
     FIG. 2 is a cross-sectional side view detail of a side wall of the water recreational apparatus illustrated in FIG. 1; 
     FIG. 3A is a cross-sectional side view detail of a side wall of the water recreational apparatus illustrated in FIG. 1 showing a biasing spring in its fully extended position and an access cover in its open position; 
     FIG. 3B is a cross-sectional side view detail of a side wall of the water recreational apparatus illustrated in FIG. 1 showing a biasing spring in its fully extended position and an access cover in its closed position; and 
     FIG. 3C is a cross-sectional side view detail of a side wall of the water recreational apparatus illustrated in FIG. 1 showing a biasing spring in its fully compressed position. 
    
    
     DETAILED DESCRIPTION 
     The following discussion describes in detail one embodiment of the invention and several variations of that embodiment. This discussion should not be construed, however, as limiting the invention to those particular embodiments. Practitioners skilled in the art will recognize numerous other embodiments as well. 
     The invention is a water recreational apparatus  10  comprising a water basin  12 , a filter  14  and a pump  16 . In the invention, one or more of the side walls  18  of the water basin  12  comprise one or more side wall doors  20  to allow the flow of water from the water basin  12  to the filter  14 . 
     The water recreational apparatus  10  can be a portable spa, hot tub, above ground pool or recirculation bath tub or similar device. The water basin  12  typically has a plurality of side walls  18  and a bottom wall  22 . 
     The filter  14  is typically disposed external of the water basin  12 . The filter  14  has an upstream side  24  and a downstream side  26 . The upstream side  24  of the filter  14  is connected to the water basin  12  by a filter inlet chamber  28 . 
     The pump  16  is typically a centrifugal pump, driven by an electric motor  30 . The pump  16  has a suction side  32  and a discharge side  34 . The suction side  32  of the pump  16  is connected via suction side circulation lines  36  to the downstream end of the filter  14 . The discharge side  34  of the pump  16  is connected via discharge side circulation lines  38  to inlet openings  40  disposed in the side walls  18  of the water basin  12 . The inlet openings  40  are typically air/water spa jets. 
     The one or more side wall doors  20  provide access from the interior of the water basin  12  to the filter inlet chamber  28 . The one or more side wall doors  20  are moveably affixed to the water basin  12  so that they can move between a closed position and an open position. When in the closed position, the side wall doors  20  are substantially flush with the side walls  18  of the water basin  12  and substantially no water can flow from the water basin  12  to the filter inlet chamber. When the side wall doors  20  are in the open position, the side wall doors  20  are substantially horizontal with respect to the side walls  18  of the water basin  12  and water can flow freely from the water basin  12 , into the filter inlet chamber  28  and then into the filter  14 . 
     Biasing means  42  are provided to bias the one or more side wall doors  20  to the closed position when the pump  16  is not operating. The biasing means  42  are configured, however, to allow the one or more side wall doors  20  to move toward the open position when the pump  16  is operating. 
     In the embodiment illustrated in the drawings, the one or more side wall doors  20  comprise a pair of side wall banks  44  disposed on opposite sides of the water basin  12 . Each side wall bank  44  has a plurality of side wall doors  28  disposed in vertical relationship with one another. Each of the side wall doors  20  is rotatably affixed to the water basin  12  in such a way that each side wall door  20  can rotate between its open position and its closed position. Each side wall door  20  is linked to a side wall door connection rod  46  which is moveable in a substantially vertical direction such that the movement of the connection rod  46  in a substantially vertical direction rotates each of the side wall doors  20  in unison between its closed position and its open position. In the embodiment illustrated in the drawings, each of the side wall doors  20  is rotatably affixed to the water basin  12  by a cam plate  48  having a pivot axis  50  and a connection rod attachment axis  52 . As can be seen in the drawings, the upward movement of the connection rod  46  rotates each of the side wall doors  20  towards the closed position, whereas the downward movement of the connection rod  46  rotates each of the side wall doors  20  towards the open position. 
     In the embodiment illustrated in the drawings, the biasing means  42  is provided by a coil spring which is attached to the connection rod attachment axis  52  on the cam plate  48  of the lowermost side wall door  20 . The lower end of the coil spring is attached to a fixed attachment element  54  disposed below the lowermost side wall door  20 . The coil spring is chosen such that each of the side wall doors  20  in the bank  44  of the side wall doors  20  is biased to the closed position when the pump  16  is not operating, but allowing the plurality of side wall doors  20  to rotate towards the open position when the pump  16  is operating. In one embodiment, the coil spring has an outside diameter of about 12 mm, an inside diameter of about 9.42 mm and an overall length (when uncompressed) of about 64.5 mm. 
     Other biasing means can also be used such as other forms of springs. The biasing means can also be a complex electronic biasing means (not shown) which include servo-motors to open and close the side wall doors  20 , door monitoring means to monitor the position of each side wall door  20 , flow monitoring means to monitor the flow of water through the water circulation lines  36  and  38  and/or an electronic controller. 
     The lowermost side wall door  20  in one or all of the side wall banks  44  further comprises an access cover  56  which can be opened by hand by tugging on a strap  58  disposed along the top of the access cover  56 . Behind the access cover  56  is a tablet compartment  60  wherein various chemical tablets, such as chlorine tablets or bromine tablets, can be retained for treating water flowing through the lowermost side wall door  20 . 
     The invention provides a water recreational apparatus which eliminates the necessity of a filter spillway. Accordingly, the spa of the invention is more efficient with respect to its top side space and is more aesthetically pleasing with respect to its appearance. 
     Having thus described the invention, it should be apparent that numerous structural modifications and adaptations may be resorted to without departing from the scope and fair meaning of the instant invention as set forth hereinabove and as described hereinbelow by the claims.