Abstract:
An in-line bubble reducer for inducing turbulent flow in a liquid fluid stream in which gaseous bubbles are entrained. The bubble reducer includes a chamber with an inlet and an outlet, an axial flow diverter for directing the fluid stream outwardly and towards a subsequent annular flow diverter. The annular flow diverter extends from an inner wall of the chamber and induces turbulent flow in the fluid stream to reduce the size of the gaseous bubbles entrained in the fluid stream.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Technical Field 
         [0002]    The present invention relates to reducing bubble size in a fluid circulation circuit. More particularly, the present invention relates to a device for reducing the size of air bubbles in a fluid circulation circuit for a spa, or whirlpool, where an air induction circuit for the spa has an ozone generator. The present invention also relates to a device that improves the efficacy of ozone bubbles to disinfect the water introduced and circulating in the spa. 
         [0003]    2. Related Art 
         [0004]    Spas and whirlpools tubs are well know in the art and are becoming increasingly popular for their therapeutic and recreational attributes. These devices include a tub to contain a volume of water that is usually large enough to accommodate at least one seated occupant. In such devices a fluid, most often water, and more particularly heated water, is circulated by a large volume capacity pumping system in which a portion of the circulated water is directed through a plurality of fluid jets disposed at various locations throughout the tub. The jets may be selectively positioned by the user so that a pressurized water flow is directed towards a particular part of the occupant&#39;s body so that the desired therapeutic effect can be obtained. 
         [0005]    To improve the therapeutic efficiency and effects of the directed water flow, the fluid circuit for the jets will normally have an air induction circuit. The air induction circuit will include an orifice having an adjustable opening that can be varied to selectively restrict or permit a desired airflow through the circuit. The air induction circuit will generally connect with the fluid circulation circuit via a venturi so that the air may be entrained in the circulating water in the fluid circuit. 
         [0006]    Due to the substantial volume of water carried in such systems it desirable that the water be retained in the tub for subsequent use, much like a swimming pool. Consequently, it is necessary that provisions be made for treating the water to avoid the growth of bacteria, algae, and other organisms, as well as to remove particulates such as dirt, leaves, grass and other contaminants that tend to accumulate in the water if left untreated. Gross contaminants are normally removed by circulation of the water through a filtration system. Fine contaminants and organism growth are generally treated chemically, such as by chlorine for disinfecting, pH stabilizers and adjusters, flocculants, and the like. 
         [0007]    Chemical treatment of the water presents its own issues. For example the costs associated with the chemicals can become prohibitive. Chemically treated water can present dermatologic issues for certain users. In addition, should it become necessary to drain the tub, disposal of the chemically treated water can potentially present environmental issues. Consequently, alternative water treatment regimens have been sought. 
         [0008]    One such alternative water treatment method includes the introduction of ozone (O 3 ) into the air induction circuit so that when circulated in the water, the ozone will treat organism growth and disinfect the water. While these systems are generally effective, current systems are inefficient in application due to the often large size of the bubbles containing the ozonized air. Moreover, when the oversized ozonized air bubbles rise to the surface and remain contained within an enclosure, such as a cover frequently used for spas, the ozone can have deleterious effects on the parts associated with the spa, particularly those made of plastics such as pads, pillows, and the cover itself. Accordingly, there remains a need for improving the efficiency of water treatment systems utilizing ozone generators and for reducing, if not eliminating the deleterious effects of ozone on the spa components. 
       BRIEF SUMMARY OF THE INVENTION 
       [0009]    Briefly, the present invention includes a method and apparatus of treating water circulated through the pump and conduit system of a spa, whirlpool, or similar device. Ozonized air is entrained with the water circulating through the system. Embodiments of the invention include structures for reducing the bubble size of the ozonized air to improve its efficacy 
         [0010]    The invention includes an apparatus comprising a bubble reducer placed in line with a conduit in the system. The bubble reducer includes a hollow chamber, an inlet at an upstream end of the hollow chamber, and an outlet at a downstream end of the chamber. The apparatus includes at least one axial flow diverter and at least one annular flow diverter contained within said chamber. The axial flow diverter has a generally dome shaped or conical first surface section axially aligned along a longitudinal axis of the hollow chamber. This first surface section directs flow through the device outwardly for passage through an aperture around the periphery of the first surface section. The annular flow diverter has a second surface comprising an annular flange having a first end proximal the inner surface of the chamber and a second end that extends inwardly and towards the inlet end of the apparatus. Additional turbulence is induced in the fluid stream when fluid directed by the first surface encounters the annular flange, with the creation of eddies in the flow near the annular flange. Fluid flow continues through an orifice defined through an axial portion of the annular flow diverter. 
         [0011]    To reduce backpressure and maintain flow through in the system, the diameter of the chamber is approximately twice that of the inlet. Similarly, the surface area of the aperture through the axial flow diverter and the orifice through the annular diverter are substantially the same as that of the inlet. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  depicts a simplified water circulation circuit for a spa. 
           [0013]      FIG. 2  depicts a side elevational view of a bubble reducer. 
           [0014]      FIG. 3  depicts a side cross-sectional view of a bubble reducer. 
           [0015]      FIG. 4A  depicts a side elevational view of an axial flow diverter. 
           [0016]      FIG. 4B  depicts a side cross-sectional view of an axial flow diverter. 
           [0017]      FIG. 4C  depicts a top plan view of an axial flow diverter. 
           [0018]      FIG. 5A  depicts a side cross sectional view of an annular flow diverter. 
           [0019]      FIG. 5B  depicts a top plan view of an annular flow diverter. 
           [0020]      FIG. 6  depicts the assembly of a bubble reducer. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0021]    A simplified water circulation circuit for a spa, whirlpool or similar apparatus is depicted in  FIG. 1 . The circulation circuit includes a tub  10  containing a large fluid volume F, typically water, a pump  11 , a suction conduit  12 , which communicates fluid F, from tub  10  to pump  11 , and an pressure conduit  13 , which communicates fluid F, under pressure, from pump  11  to tub  10 . As will be appreciated by those familiar with the art of spas, both the input and output fluid circuits, represented by suction conduit  12  and pressure conduit  13 , may have one or more manifolds (not shown) interconnecting a plurality of conduits in the respective circuits. 
         [0022]    One or more air inlet valves  14  are provided to in communication with the output circuit for selectively introducing air B into the pressurized fluid stream F, via an air conduit  15  and a venturi  16  connected to pressure conduit  13 . Valve  14  is variably operable between an open, air communicating position, and a closed, air restricting position, to control the volume of air introduced into the fluid stream F. 
         [0023]    An ozone generator  17 , or ozonizer, is positioned along air conduit  15  and is operable to ozonize the air communicated through air conduit  15  such that ozonized air is entrained in the pressurized fluid flow F. The in-line bubble reducer  20  of the present invention is positioned along output conduit  13  intermediate venturi  16  and a jet  18  directing fluid F into tub  10 . As will be appreciated, the above described components are usually contained within an enclosure  19  extending from tub  10 . 
         [0024]    In the exemplary embodiment depicted in  FIGS. 2 and 3 , the bubble reducer  20  has an inlet port  21  and an outlet port  22  to operatively couple bubble reducer  20  to conduit  13 , in any suitable manner, such as the barbed connection depicted, threaded connections, quick disconnect fittings, a nipple, or the like. Reducer  20  comprises a generally cylindrical casing  23  enclosing at least one axial flow diverter  30  and at least one annular flow diverter  40 . To avoid introducing significant back pressure in the fluid flow F, the inner diameter of casing  23  should be substantially larger than that of the inner diameter of inlet  21  or conduit  13 , preferably about twice as large. Fluid flow F through proceeds from inlet  21 , through casing  23 , and then outlet  22 , as indicated by flow arrow F. Preferably inlet  21 , casing  23 , and outlet  22  are coaxially aligned. 
         [0025]    While the bubble reducer of the present invention may be made of any suitable material, plastics, such as for an illustrative example PVC, provide a convenient, cost effective means for producing the same. In the embodiment shown, casing  23  is comprised of a elongated hollow cylindrical member in which a barbed inlet  21  is integrally formed to provide a watertight seal. The outlet port  22  may comprise a barbed fitting  25  that may be sealingly attached to reducer  20  by any suitable means, such as adhesives, sonic welding, or even threaded engagement. 
         [0026]    At least one axial flow diverter  30  having a first surface  31  disposed in alignment with inlet  21  such that fluid flow F encounters first surface  31  and is directed radially outwardly towards an inner surface  24  of casing  23  and at least one aperture for passage of fluid F through axial flow diverter  30 . As may best be seen in reference to  FIGS. 4A ,  4 B, and  4 C, an exemplary embodiment of an axial flow diverter  30  is shown in which axial flow diverter  30  comprises a generally dome shaped or conic surface section  31  oriented with an apex of conic section  31  projecting towards inlet  21  and a base of conic surface  31  projecting towards outlet  22 . More preferably, conic surface  31  is coaxially aligned with inlet  21 . In the embodiment shown, conic surface  31  is maintained in position by a plurality of support members  32  extending radially outward from conic surface  31  and supported against an inner surface  24  of casing  23 . Preferably, the base  34  of conic surface  31  will have a diameter approximately one half that of casing  23  such that apertures  35  defined between base  34 , support members  32  and inner surface  24 , will have a combined surface area substantially the same or larger than that of inlet  22 . Flow of fluid F through axial flow diverter  30  occurs through apertures  35  around the periphery of base  31 . 
         [0027]    Support members  32  may be vertically disposed in substantial alignment with a longitudinal axis A of reducer  20 , so as limit disruptions fluid flow F. Alternatively, support members may be angled with respect to axis A, so as to present a lateral surface  36  in the fluid flow F, to provide additional fluid flow F disruptions. For ease of assembly, support members  32  may be interconnected by an annular support  33 . More preferably, annular support  33  can have an elongated sidewall  37  having an outer surface that is substantially parallel to and dimensioned to fit in abutment with inner surface  24 . Sidewall  37  should have a length corresponding to the height of conic surface  31 , such that axial flow diverter  30  is substantially disc shaped. The disc shaped axial flow diverter  30  is readily insertable within casing  23 , as depicted in  FIG. 6 . 
         [0028]    As may best be seen in reference to  FIGS. 5A  and B, an exemplary embodiment of an annular flow diverter  40  is depicted in which annular flow diverter  40  comprises a tapered annular flange  41  having a first end  42  proximal to casing inner surface  24  and a second end  43  that extends inwardly towards axis A, and projects upstream, towards inlet  21 , such that second end  43  defines an orifice  44  concentric with casing  23  and a lip  47  to induce eddies in fluid flow F. In the preferred embodiment shown, annular flange  42  is shaped as conic extension of axial flow diverter  30 , such that orifice  44  has a diameter corresponding to the diameter of base  34 . 
         [0029]    For ease of assembly, an annular sidewall  45  surrounds flange  41  at its first downstream end  42  and extends upstream, substantially parallel with axis A, towards inlet  22 , such that annular flow diverter  40 , like axial flow diverter  30 , is essentially disc shaped and easily insertable within chamber  23 , as depicted in  FIG. 6 . In this instance, annular sidewall  45  has a longitudinal length that is greater than the height of tapered flange  41  so as to provide sufficient longitudinal spacing between the base  34  of axial diverter  30  and aperture  44  to permit fluid flow F through the device  20 . Preferably, orifice  42  has a cross sectional area substantially the same as that of inlet  22 . Support members  46  may be provided to support annular flange  42  with sidewall  45 . 
         [0030]    Referring back to  FIG. 3 , axial diverter  30  and annular diverter  40  are disposed within casing  23  in at least one paired configuration to sequentially divert fluid flow F throughout the longitudinal length of reducer  20 . Upon entry through inlet port  21 , fluid F encounters conic surface  31  which diverts the fluid stream outwardly towards casing inner surface  24 . As the fluid stream encounters inner surface  24  and annular flow diverter  40 , eddies are formed in proximity to lip  47 , permitting large bubbles of ozonized air to break apart and achieve greater dispersion of within fluid F as it passes through orifice  42 . As may be seen, additional pairs of alternating axial flow diverters  30  and annular flow diverters  40  may be sequentially disposed to further mix the ozonized air in fluid F. Ideally, a sufficient number of paired diverters are included within casing  20  so that large undesired bubbles may be completely reduced so as to impart substantially smaller bubbles of ozonized air into the fluid stream F With the substantially reduction in the size of the ozonized bubbles in the fluid F, the ozone can more efficiently disinfect fluid F. 
         [0031]    It will be appreciated that each additional pair of axial  30  and annular  40  flow diverters will tend to increase the back pressure in the system. Accordingly, for optimum performance, the selection of the number and flow characteristics of the bubble reducer  20  should be appropriately matched to the respective circulation system. 
         [0032]    While certain exemplary embodiments of the invention have been described in considerable detail, by way of illustration and for clarity of understanding, a number of modifications, adaptations, and changes will be recognized to those of skill in the art. Accordingly, the scope of the present invention is limited solely by the appended claims.