Abstract:
A filter system includes a conduit for fluidly interfacing to a pump and a shroud adapted to be in fluid communication with a body of water in a spa/tub. A stand pipe has a first end structurally affixed to a bottom surface of the shroud. The first end of the stand pipe is fluidly interfaced to the conduit for transference of water to a pump. A distal second end of the stand pipe has a bypass valve and the stand pipe is sized and positioned within the shroud for holding and supporting a filter media.

Description:
[0001]    This application is related to U.S. design patent application titled Spa Jet Design, attorney docket number 2699.13, filed evendate herewithin. This application is also related to U.S. patent application titled Spa Jet Interface, attorney docket number 2699.10, filed evendate herewithin. This application is also related to U.S. patent application titled Method of Forming Spa Jet Interface, attorney docket number 2699.11, filed evendate herewithin. This application is also related to U.S. patent application titled Improved Spa Jet, attorney docket number 2699.12, filed evendate herewithin. 
     
    
     FIELD 
       [0002]    This invention relates to the field of spa/pools and more particularly to a system for improved filter bypass operation. 
       BACKGROUND 
       [0003]    Practically every pool, hot tub, and spa has a filter. Periodically, the water in the pool, hot tub, or spa is pumped through the filter to remove small organisms and any other suspended solid materials to clean the water and keep the water clear. There are many types and configurations of filters and an equal number of filter media. For hot tubs and spas, a paper filter is typically fluidly inserted between the skimmer and the pump. The skimmer is typically a waterfall-type device such that any items floating on the water will eventually float over the skimmer and through the filtration system. 
         [0004]    As suspended particles are captured in pores of the filter, the ability of water to flow through the filter reduces. Periodically, the filter needs to be changed, cleaned, or backwashed to unclog the pores. The pump will try to move the requisite number of gallons per minute through the filter, independent of the permeability of the filter. If proper maintenance is not performed on the filter, and permeability is reduced beyond a certain point, a filter bypass valve opens to relieve the pressure on the outside surface of the filter and prevent either overload of the pump motor and/or rupture of the filter media. 
         [0005]    Many designs use a simple spring-loaded flapper valve between the filter inlet and the pump. The spring is selected to hold the valve substantially closed until a certain pressure is reached, at which time the flapper valve opens and allows water to flow through the bypass, thereby preventing an overload of the pump motor and/or rupture of the filter media. 
         [0006]    Being that the bypass valve is typically submerged in the pool/spa water which typically contains an oxidizer such as bromine or chlorine to control biological growth, the bypass valve often clogs or the spring fails, allowing water to freely flow through the bypass valve and, since little or no water flows through the filter, the filter is rendered useless. Repair of the bypass valve is not an easy task. The bypass valve is often located within/beneath the plumbing of the filter enclosure, beneath the filter media holding area and in an area that requires major dismantling in order to access and repair a broken bypass valve. 
         [0007]    What is needed is a filter system that will provide robust bypass and improved reparability of the bypass valve. 
       SUMMARY 
       [0008]    In one embodiment, a filter system is disclosed including a conduit for fluidly interfacing to a pump and a shroud adapted to be in fluid communication with a body of water. A stand pipe has a first end structurally affixed to a bottom surface of the shroud. The first end of the stand pipe is fluidly interfaced to the conduit. A distal second end of the stand pipe has a bypass valve and the stand pipe is sized and positioned within the shroud for holding and supporting a filter media. 
         [0009]    In another embodiment, a filter system is disclosed including a shroud. The shroud has an opening for accepting water from a tub/spa and a stand pipe. A first end of the stand pipe is structurally affixed to the shroud. A filter media is mounted on the stand pipe and the filter is fluidly positioned between the shroud opening and the stand pipe. A bypass valve which is normally closed is mounted on and covers a distal end of the stand pipe. 
         [0010]    In another embodiment, a method of replacing a failed bypass valve with a replacement bypass valve is disclosed including providing a filter system as described above and removing the strainer from the second end of the stand pipe by unthreading the strainer. Next, the failed bypass valve is removed from the second end of the stand pipe by pulling the failed bypass valve out of second end of the stand pipe. The replacement bypass valve is then installed by pushing the replacement bypass valve into the second end of the stand pipe. The strainer is then replaced on the second end of the stand pipe by threading the strainer onto the threads of the second end of the stand pipe. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The invention can be best understood by those having ordinary skill in the art by reference to the following detailed description when considered in conjunction with the accompanying drawings in which: 
           [0012]      FIG. 1  illustrates a cross sectional view of a typical filter system with bypass valve of the prior art. 
           [0013]      FIG. 2  illustrates a plan view of the filter and bypass valve having improved serviceability. 
           [0014]      FIG. 3  illustrates an exploded view of the filter and bypass valve having improved serviceability. 
       
    
    
     DETAILED DESCRIPTION 
       [0015]    Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Throughout the following detailed description, the same reference numerals refer to the same elements in all figures. 
         [0016]    Referring to  FIG. 1 , a cross sectional view of a typical filter system  200  with bypass valve  232  of the prior art is shown. In this filter system  200  of the prior art, water flows from one or more sources such as a drain that pulls in heavier suspended particles and/or a skimmer that pulls in floating particles (not shown for clarity reasons). The water enters the filter system  200  through an inlet  214 . The filter media  220  is held within a filter shroud  218  such that the top opening of the filter media  220  is closed by a plug  212 . The plug  212  is typically part of a removable lid  210  that enables removal of the filter media  220  for cleaning and/or for changing the filter media  220 . The bottom center hole of the filter media  220  rests on a stand pipe  230 . The stand pipe  230  fluidly interfaces the inner area of the filter media  220  with an outlet  216 . The outlet  216  is in fluid communication with the pump (not shown). 
         [0017]    Water surrounds the filter media  220  and as the pump operates, water is pulled from the center of the filter media  220  and replaced by water surrounding the filter media  220 , forcing most of the water to flow through pores in the filter media  220 . As particles that are suspended in the water try to pass through the pores (not visible) in the filter media  220 , they are blocked and clog the pores of the filter media  220 . The particles get lodged in the pores of the filter media  220 . The result is clean water (or cleaner water) passes out the outlet  216  to the pump. 
         [0018]    As the particulate clogs more and more pores, less open pores are available for the flow of water through the filter media  220 . If proper maintenance is not performed such as removal and cleaning of the filter media  220  or replacement of the filter media  220 , eventually, less and less water can flow through the filter media  220 . As the filter media becomes less and less porous, the suction from the pump creates a greater pressure on the walls of the filter media  220 . To prevent the pump from overload and/or a rupture of the filter media  220 , many spa systems have a filter bypass valve  232  that is typically held closed by a spring, but at a certain pressure, opens and allows a flow of water from the inlet  214  side to the outlet  216  side of the filter bypass valve  232 , thereby reducing the pressure on the clogged filter media  220  and reducing the load on the pump. This reduces cleaning of the water but often saves replacement of a ruptured filter media  220  or a failed pump. 
         [0019]    As shown, the filter bypass valve  232  is typically submerged in water, even when the spa is not in use. The filter bypass valve  232  is affected by several materials in this water. First, if the spa water is not maintained correctly, biological material and/or minerals will deposit on the filter bypass valve  232 , perhaps causing the filter bypass valve  232  to lock shut or leak. If the filter bypass valve  232  is locked shut, it will no longer protect the pump and the filter media  220 . If the filter bypass valve  232  leaks or is stuck in an open position, the filter bypass valve  232  will constantly allow the spa water to bypass the filter media  220  and there will be little or no filtration performed. Another factor is corrosion. To reduce biological material presence in the spa water, an oxidant such as chlorine or bromine is typically added to the water. These oxidants not only destroy microbes, but work continuously against any metal parts to which they are exposed, including the spring of the filter bypass valve  232 . Eventually the spring weakens or breaks and the resistance to the filter bypass valve  232  opening subsides and the spa water eventually flows freely through the filter bypass valve  232 . 
         [0020]    When such failures to the filter bypass valve  232  occur, it is often difficult to replace the filter bypass valve  232  because of its location beneath the filter shroud  218  and filter stand pipe  230 . For most existing spas, this becomes a major repair job even though the filter bypass valve  232  is a very low cost item. 
         [0021]    Referring to  FIG. 2 , a plan view of the filter system  250  with filter media  270  and bypass valve  282  having improved serviceability is shown. In this example, the filter media  270  is surrounded by a shroud  278  such that water flows over a lip of the shroud  278  (e.g. a weir) and surrounds the filter media  270 . As water flows through the filter media  270  (e.g. is drawn by the pump—not shown), the water flows through pores of the filter media  270  and through a stand pipe  284  and towards the pump through an outflow pipe  266 . A flange  280  in or affixed to a bottom area of the stand pipe  284  maintains a proper position of the filter media  270 . The stand pipe  284  provides support and structure for the filter media  270  and also provides support for the filter bypass valve  282  and the optional bypass valve strainer  264 . 
         [0022]    The filter bypass valve  282  is hinged downwardly in the view of  FIG. 2  and is held closed by, for example, spring force or gravity; though any known bypass valve is anticipated. Water substantially surrounds the filter media  270  and as the pump operates, water is pulled from the center of the filter media  270  and replaced by water surrounding the filter media  270 , forcing most of the water to flow through pores in the filter media  270 . As particles that are suspended in the water try to pass through the pores (not visible) in the filter media  270 , they are blocked and clog the pores of the filter media  270 . The particles get lodged in the pores of the filter media  270 . The result is clean water (or cleaner water) passes out the outlet  266  to the pump. 
         [0023]    As the particulate clogs more and more pores in the filter media  270 , less open pores are available for the flow of water. If proper maintenance is not performed such as removal and cleaning of the filter media  270  or replacement of the filter media  270 , eventually, less and less water can flow through the filter media  270 . As the filter media becomes less and less porous, the suction from the pump creates a greater pressure on the walls of the filter media  270 . To prevent the pump from overload and/or a rupture of the filter media  270 , a filter bypass valve  282  is normally held closed by, for example, a spring. As the pressure increases due to this clogging, the filter bypass valve  282  opens and allows a flow of water from the between the shroud  278  and the outer surface of the filter media  270  through the filter bypass valve  282  and to the outlet  266  and pump. This bypass reduces the pressure on the clogged filter media  270  and reduces the load on the pump. Even though the bypass action reduces cleaning of the water, this bypass often saves replacement of a ruptured filter media  270  or a failed pump. 
         [0024]    As shown, the filter bypass valve  282  is typically submerged in and/or exposed to water, even when the spa is not in use. The filter bypass valve  282  is likewise affected by several materials in this water. First, if the spa water is not maintained correctly, biological material and/or minerals will deposit on the filter bypass valve  282 , perhaps causing the filter bypass valve  282  to lock shut or leak. If the filter bypass valve  282  is locked shut, it will no longer protect the pump and the filter media  270 . If the filter bypass valve  282  leaks or is stuck in an open position, the filter bypass valve  282  will constantly allow the spa water to bypass the filter media  270  and there will be little or no filtration performed. Another factor is corrosion. To reduce biological material presence in the spa water, an oxidant such as chlorine or bromine is typically added to the water. These oxidants not only destroy microbes, but work continuously against any metal parts to which they are exposed, including the spring of the filter bypass valve  282 . Eventually the spring weakens or breaks and the closing force of the filter bypass valve  282  subsides and the spa water eventually flows freely through the filter bypass valve  282 . 
         [0025]    When such failures to the filter bypass valve  282  occur, replacement of the filter bypass valve  282  is simplified by the location of the filter bypass valve  282  atop the standpipe  284 . Replacement now becomes a simple task of removing the failed filter bypass valve  282  and installing a new filter bypass valve  282 . Any type of retaining mechanism is anticipated to hold the filter bypass valve  282  onto the stand pipe  284 , including rotational engagement, threaded engagement, snap engagement, magnetic, fasteners, etc. The retainment mechanism for the filter bypass valve  282  in some embodiments also holds/retains the filter media  270  in place. In the exemplary system shown, the filter media  270  and the bypass valve  282  are held onto the standpipe  284  by threading the strainer  264  onto threads at the top of the stand pipe  284  (as shown in  FIG. 3 ). 
         [0026]    In some embodiments, as shown in the examples, the filter media  270  has an oval cross-sectional shape and the stand pipe  284  also has an oval cross-sectional; shape in the area where it mates with the inner wall of the filter medial  270 . This oval-shaped filter media  270  provides increased filter surface area (e.g. a greater number of pores) given a certain width over a similar sized filter media that is round. In such, a greater filter area is achieved without increasing the amount of depth required by the filter. In other words, the filter shroud  278  need not protrude as far into the spa using the oval filter media  270  as shown compared with a round filter media  270  (not shown) having equivalent surface area. In other embodiments, any size and shape of filter media  270  is anticipated, including filter media  270  that have round/circular cross sectional shapes and/or irregular shapes. 
         [0027]    Referring to  FIG. 3 , an exploded view of filter system  250  with filter media  270  and bypass valve  282  having improved serviceability is shown. 
         [0028]    In this, the general oval cross-sectional shape of the filter media  270  is visible. The flange  280  is attached to a coupling  281 , by threads as shown, but any attachment mechanism is anticipated. The flange  280  holds the shroud  278  to the coupling  281  and, subsequently, to the pip/tube  266  (see  FIG. 2 ) that is fluidly coupled to the pump (not shown). The stand pipe  284  attaches to the coupling  281  by any attachment system known, including threads as shown. 
         [0029]    The filter media  270  fits over the stand pipe  284 . In some embodiments, outer dimensions of the stand pipe  284  are similar to inner dimensions of the filter media  270 , such that the inside surface of the filter media  270  rests against the outer surfaces of the stand pipe  284 , thereby providing added structure to the filter media  270 , especially when the filter media  270  becomes clogged enough as to increase the pressure on the filter media  270 . 
         [0030]    Although there are many ways to mount the bypass valve  282 , in the example shown, a lip of the bypass valve  282  rests on an upper surface of the stand pipe  284  by way of the lip having an outer diameter greater than the inner diameter of the end of the stand pipe  284 . The strainer  264  has an inner threaded interface that matches an outer threaded interface of the top end of the stand pipe  284 , such that the strainer  264  threads over the outer threaded interface of the top end of the stand pipe  284 , thereby secures the bypass valve  282  to the stand pipe  284 . Note that the outer diameter of the bypass valve  282  need be small enough such that the strainer  264  will fit over the bypass valve  282 . In operation, the filter media  270  is placed over the stand pipe  284 , and then the strainer  264  is threaded over the threaded end of the stand pipe  284 , thereby retaining the filter media in place. Again, this is an example of one way in which the filter media  270  and bypass valve  282  are properly positioned and connected and any mechanism and architecture is anticipated, producing similar results. 
         [0031]    Should the bypass valve  282  fail, the strainer  264  is removed (e.g. unscrewed) and the bypass valve  282  is lifted out of the end of the stand pipe  284 . Note that in some embodiments, the bypass valve  282  is held in the end of the stand pipe  284  by any known mechanism, including, but not limited to, threads, press-fit, detents, etc. The new bypass valve  282  is then installed into the end of the stand pipe  284  and the strainer  264  is replaced (e.g. screwed back onto the threaded end of the stand pipe  284 ). 
         [0032]    Equivalent elements can be substituted for the ones set forth above such that they perform in substantially the same manner in substantially the same way for achieving substantially the same result. 
         [0033]    It is believed that the system and method as described and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely exemplary and explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.