Abstract:
The present invention relates to a plumbing connection useful in the field of fluid transfer, including in many stages of beer brewing operations, to connect to a fluid inlet or outlet in which the plumbing connection includes a threaded, compressible bushing that compressibly grips a tube when tightened to make a plumbing connection.

Description:
PRIORITY CLAIM 
       [0001]    This application claims priority to U.S. Provisional Patent Application No. 62/082,870, filed Nov. 21, 2014, the entire contents of which are incorporated herein by reference in their entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention is in the field of plumbing connections that connect to fluid inlets and outlets of fluid holding vessels. More particularly, the present invention relates to a plumbing connection useful in the field of beer brewing to connect to a fluid inlet or outlet in which the plumbing connection includes a threaded, compressible bushing that compressibly grips a tube when tightened to make a plumbing connection. 
       BACKGROUND OF THE INVENTION 
       [0003]    Many consumer and industrial processes involve transferring fluids to and from vessels in which the liquids are stored, reacted, modified, or otherwise handled. Typically, inlet and outlet plumbing components are connected to a vessel in order to feed or withdraw fluids from the vessel. In order to create fluid tight couplings, these coupling structures can be quite complex, involving several tubes or pipes, coupling elements, valves, gaskets, and the like. Manufacture, installation, adjustment, positioning, repair, cleaning and sanitizing, and use are more difficult than desired when so many components are involved. 
         [0004]    The process of brewing beer, either on a commercial or home brewing scale, is an illustrative context in which plumbing components are connected to inlets and outlets of several processing vessels. Typically, beer brewing involves process steps such as malting, milling, mashing, lautering, boiling, fermenting, conditioning, filtering, and packaging. For example, the boiling step typically occurs in a kettle. Ingredients often including water, one or more sugar sources including malted barley, and hops, are boiled to accomplish objectives including sterilization of the wort to remove unwanted bacteria, releasing of hop flavors, stopping enzymatic processes, precipitation of proteins, volatilize off-flavors, and concentration of the wort. 
         [0005]    At the end of the boil, the kettle generally includes the desired liquid phase and a solid phase referred to as the trub. A whirlpool effect may be used to collect solids in the bottom center region of the kettle, while the desired liquid product is drained from the perimeter of the kettle. A kettle generally includes a drain conduit to drain the liquid. A valve typically is provided outside the kettle to open and close the drain. A drain system includes a pickup tube or other inlet structure through which the liquid enters the drain system. 
         [0006]    Kettles marketed for home brewing are supplied with a drain structure included threaded bosses on the inside and outside of the kettle. The bosses are used to connect the desired plumbing components. It is desirable that the plumbing connections at the drain are fluid-tight so that the kettle does not leak. Examples of commercially available brew kettles with such drain fittings are available under trade designations MegaPot 1.2 and Polar Ware. 
         [0007]    A common practice in home brewing is to attach a pick up tube to the inside of the kettle drain for withdrawing the liquid. Conventional practice involves using coupling components, gaskets, and the like to make the plumbing connection. This involves many components to install. The large number of components to connect makes installation, cleaning and sanitizing, use, adjustment, and removal more cumbersome than might be desired. Home brewers actively investigate better ways to couple interior drain components to the drain of a brew kettle. Another concern is to use a pick up strategy that drains as much of the liquid as practically feasible while leaving as much of the solids behind. 
         [0008]    For example, a current beer brewing blog is at www.morebeer.com. Blog participants have discussed strategies for devising a better pick up to attach to the drain boss on a brew kettle. In one discussion, a blog participant described a pick up strategy in which a pick up tube is coupled to the drain boss with a 90 degree elbow. The pick-up tube is aimed sideways. The participant wanted a better strategy, as this one left 1.5 gallons behind in the kettle. The same participant later modified this strategy by aiming the tube downward, but still used the 90 degree elbow and plumbers tape at the connections. 
         [0009]    Another blog participant used a threaded coupling, a 90 degree elbow and a tube aimed sideways. Connections between the components were soldered, making adjustment impractical. A gasketing material was used between the drain boss and the coupling. 
         [0010]    The popularity of home brewing continues to increase. The demand for better fluid coupling strategies for brewing equipment such as boiling kettles remains strong. 
       SUMMARY OF THE INVENTION 
       [0011]    The present invention is in the field of plumbing connections that connect to fluid inlets and outlets of fluid holding vessels. More particularly, the present invention relates to a plumbing connection useful in the field of beer brewing to connect to a fluid inlet or outlet in which the plumbing connection includes a threaded, compressible bushing that compressibly grips a tube when tightened to make a plumbing connection. 
         [0012]    Embodiments of the present invention are easy to install and use. In one illustrative mode of practice, a tube is used to pick up liquid, e.g., wort, from inside a vessel such as a brew kettle, tank, cooler, reaction vessel, or the like. Initially, the tube is inserted into a compressible bushing with a press fit between the tube and bushing. The bushing is then screwed into a complementary coupling on the vessel. Tightening the bushing causes the bushing to increasingly grip the tube as well, as the coupling. As the bushing is tightened, the tube is rotated within the bushing to aim the tube into the interior volume of the vessel as desired. While holding the tube in the desired aim, the bushing is fully tightened to the degree desired. As a consequence, the tube is coupled to the tank with fluid tight seals between the bushing and the tube and between the bushing and the vessel. The bushing functions as the attachment component, the gripping component, and the gasket component. 
         [0013]    In one aspect, the present invention relates to a brew kettle system, comprising:
       (a) a kettle comprising
           (i) an interior volume   (ii) a boundary between the interior volume and an exterior region; and   (iii) a conduit fluidly coupling the interior volume to the exterior region, wherein the conduit comprises a female-threaded portion threadably accessible from the interior volume and a second portion accessible from the exterior region; and   
           (b) a pick up tube assembly, comprising:
           (i) a compressible bushing, comprising:
               a compressible body comprising male threads on at least a portion of an exterior surface of the compressible body, wherein the male threads of the compressible body are threadably engaged with the female threads of the female-threaded portion of the conduit; and   a through bore extending from a first end of the body to a second end;   
               (ii) a tube having a first port at a first end that opens toward the interior volume of the kettle and a second port at a second end that opens toward the exterior region, wherein at least a portion of the tube is positioned in the through bore of the compressible bushing, and wherein the compressible body is configured in a manner such that the threadable engagement between the conduit and the compressible bushing compresses the bushing body to cause the compressible body to compressibly and sealingly engage the tube portion that is positioned in the through bore.   
               
 
         [0023]    In another aspect, the present invention relates to a method of fluidly coupling an interior volume of a kettle to and an exterior region, comprising the step of providing a kettle system according to the above. 
         [0024]    In another aspect, the present invention relates to a method of heating a wort admixture, comprising the steps of:
       (a) providing a kettle system according to claim  1 ;   (b) causing the wort admixture to be held in the kettle;   (c) while the wort admixture is held in the kettle, heating the wort; and   (d) after heating the wort, withdrawing at least a portion of the wort admixture through a fluid pathway comprising at least the tube portion that is compressibly and sealingly engaged by the compressed bushing body.       
 
         [0029]    In another aspect, the present invention relates to a pick up tube assembly, comprising:
       (a) a compressible bushing, comprising:
           (i) a compressible body comprising male threads on at least a portion of an exterior surface of the compressible body, wherein the male threads of the compressible body are configured to threadably engage with the female threads of a female-threaded portion of a conduit accessible from an interior volume of a brew kettle; and   (ii) a through bore extending from a first end of the body to a second end;   
           (b) a tube having a first port at a first end that opens toward the interior volume of the kettle and a second port at a second end that opens toward the exterior region, wherein at least a portion of the tube is positioned in the through bore of the compressible bushing, and wherein the compressible body is configured in a manner such that a threadable engagement between the conduit and the compressible bushing compresses the bushing body to cause the compressible body to compressibly and sealingly engage the tube portion that is positioned in the through bore.       
 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0034]      FIG. 1  is a schematic side view of a brew kettle system of the present invention shown in cross-section. 
           [0035]      FIG. 2  is a side view of the brew kettle of  FIG. 4  with a bottom portion of the brew kettle cut away to better show the drain features. 
           [0036]      FIG. 3  is a perspective view of a pick up tube assembly of the present invention used in the brew kettle system of  FIG. 1 . 
           [0037]      FIG. 4  is a front view of the pick up tube assembly of  FIG. 3 . 
           [0038]      FIG. 5  is a side view of the pick up tube assembly of  FIG. 6  with the pick up tube shown in cross-section. 
           [0039]      FIG. 6  is a perspective view of the compressible bushing used in the pick up tube assembly of  FIG. 3 . 
           [0040]      FIG. 7  is a side view of the compressible bushing shown in  FIG. 6 . 
           [0041]      FIG. 8  is a side cross section view of the compressible bushing of  FIGS. 6 and 7  in which the cross section is taken along line A-A of  FIG. 7 . 
       
    
    
     DETAILED DESCRIPTION 
       [0042]    The embodiments of the present invention described below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather a purpose of the embodiments chosen and described is so that the appreciation and understanding by others skilled in the art of the principles and practices of the present invention can be facilitated. 
         [0043]    An illustrative embodiment of a brew kettle system  10  of the present invention is shown in  FIGS. 7 through 8 . Brew kettle system  10  generally includes kettle  12  and a pick up tube assembly  52 . Kettle  12  can be fabricated from a wide range of material(s). Kettle  12  desirably is fabricated from one or more materials suitable for heating wort (not shown) in the process of beer brewing. Suitable materials are strong and durable, chemically and physically resistant to the wort during heating, and are easy to clean and sterilize. Examples of suitable materials include stainless steel, aluminum, copper, brass, other metal or metal alloys, heat-resistant glass, combinations of these, and the like. 
         [0044]    Kettle  12  includes tub  14  having a generally cylindrical sidewall  16 , floor  24 , and cover  26 . Together, sidewall  16 , floor  24 , and cover  26  provide a housing enclosing interior volume  35 . Although shown with a cylindrical geometry, sidewall  16  can have other geometries if desired. Sidewall  16  extends from top rim  18  to bottom rim  20 . Top rim  18  flares outward to help stiffen sidewall  16 . Top rim  18  defines an opening for accessing interior volume  35  of kettle  12 . Handles  32  are attached to sidewall  16  to facilitate lifting, carrying, moving, tipping, holding, or otherwise handling kettle  12 . 
         [0045]    Floor  24  is attached to sidewall  16  proximal to bottom rim  20 . Floor  24  can be a separate component from sidewall  16 . Alternatively, floor  24  and sidewall  16  can be integrally formed as a single component. In this embodiment, floor  24  is general flat. In other embodiments, floor  24  can be convex, concave, corrugated, or otherwise contoured to help stiffen floor  24 . 
         [0046]    Cover  26  fits over top rim  64  of sidewall  16  and is removable on demand by simply lifting or lowering to open or close kettle  12  as desired. Cover  26  includes panel  28  extending across tub opening  19  and a flange  30  extending downward from panel  28  to fit around top rim  18 . Cover  26  includes handle  34  to help the user hold cover  26 . In many suitable embodiments, cover  26  simply sets down onto top rim  18  and is held in place by gravity. In other embodiments, cover  26  may be sized and/or include features that allow cover  26  to be secured in place onto tub  14 . Examples of securing options include snap fit engagement, threaded engagement, latches, combinations of these, or the like. Because heating wort can generate pressure in the headspace above the wort, kettle  12  desirable is fitted with relief valve features (not shown) in those embodiments in which cover  26  is secured in some fashion to tub  14 . 
         [0047]    After heating wort to the desired degree, the wort is desirably removed from tub  12  and transferred to further apparatus to continue the brewing process. Rather than have to lift and tip kettle  12  to transfer the hot wort, it is more desirable and easier to drain the hot wort from a suitable fluid egress proximal to the floor of  24 . Desirably, the intake for the fluid egress is positioned as close as possible to the floor  24  so that as much wort as practically possible is drained from kettle  12  and as little wort as practically possible is left behind. To this end, tub  14  includes fluid drain coupling  36  positioned on sidewall  16  proximal to floor  24 . Fluid drain coupling  36  provides a fluid egress to allow fluid contents to be drained from and/or transferred into interior volume  35 . 
         [0048]    Fluid drain coupling  36  includes a tube boss  38  projecting into interior volume  35  and a tube boss  40  projecting outward into the exterior region  41  outside of kettle  12 . A channel  42  extends from port  44  on interior tube boss  40  to port  46  on exterior tube boss  40 . Channel  42  allows fluids to flow between interior volume  35  and exterior region  41 . Tube boss  38  includes female threads  48  to allow pick up tube assembly to be easily coupled to tube boss  38 . Similarly, boss  40  also desirably includes one or more coupling features (not shown) to allow plumbing components (not shown) to be coupled to boss  40 . Examples of coupling features include male threads, female threads, barbs, band clamps, quick release fittings, hatches, valves, snap fittings, combinations of these, and the like. 
         [0049]    As illustrated, brew kettle system  10  is shown as including one fluid drain coupling  36 . In alternative embodiments, system  10  optionally may include one or more additional fluid drain couplings or other features to allow fluids to be transferred to and from kettle  12 . Such optional fluid transfer features may be positioned at any location(s) such as on sidewall  16 , floor  24 , and/or cover  26 . 
         [0050]    Pick up tube assembly  52  includes a pick up tube  54  gripped by compressible bushing  66 , which in turn is threadably engaged with tube boss  38 . Pick up tube extends from first end  56  to second end  58 . First end  56  is located inside interior volume  35 . In this embodiment, second end  58  extends toward port  46  of boss  40 . 
         [0051]    Pick up tube has bend  60  with pick up arm  62  extending into interior volume  35  and drain arm  64  extending toward exterior region  41 . Pick up tube  54  is hollow to provide a fluid flow channel  61  extending from a first port  63  to second port  65 . When draining fluid from kettle  12 , first port  63  serves as an inlet into pick up tube  54 , and second port  65  serves as an outlet from pick up tube  54 . As shown in the Figures, tube  54  is oriented so that pick up arm  62  is oriented downward toward floor  24 . In other modes of practice, drain arm  64  can be rotated inside compressible bushing  66  in order to aim pick up arm  62  in an alternative direction, e.g., diagonally downward, to the side, diagonally upward, upward, or the like. 
         [0052]    Compressible bushing  66  is threadably engaged with tube boss  38  and grips pick up tube  54 . The threadable engagement with tube boss  38  occurs a manner such that the interface between tube boss  38  and bushing  66  is fluid tight. Similarly, compressible bushing  66  grips tube  54  also in a manner such that the interface between bushing  66  and tube  54  is fluid tight. In this manner, bushing  66  serves not only as a way to physically couple itself and tube  54  to tube boss  38 , but also as a gasket to help create fluid tight seals. Consequently, fluid such as wort drains from tube  14  through pick up tube  54  and is substantially prevented from, more desirably completely prevented from, seeping out from tub  14  via the interfaces between the tube boss  38 , bushing  66 , and tube  54 . The fluid tight seal at the interfaces is also important to facilitate a siphon action when such an action is desired for drawing fluid up into the pick up tube  54 . The siphon action helps to maximize the amount of wort recovered from the brew kettle after heat treatment of the wort is completed. The siphon action is particularly important when the pick up arm  62  of the pick up tube  54  is aimed downward so that first port  63  is close to the bottom of the kettle  12  and where the level of the wort being withdrawn has dropped below bend  60 . 
         [0053]    Compressible bushing  68  includes a resiliently compressible body  68  extending from first end  70  to second end  72 . The external surface  76  of body  68  includes male threads  74 . The male threads  74  are threadably engaged with the female threads  48  inside tube boss  38 . Head  78  is provided at first end  70 . Head has a faceted external shape so that head can be gripped with a suitable tool, e.g., pliers, wrench, socket, or the like, to threadably engage or disengage bushing  68  with or from bore  38 . Head  78  may be a separate component that is attached to body  68 . More desirably, head  78  and body  68  are integrally formed as a single component. 
         [0054]    Compressible bushing  68  is hollow and includes cylindrical interior wall  80  defining a channel  82  extending through bushing  68  from first end  70  to second end  72 . When compressible bushing has not yet been threadably engaged with bore  38 , channel  82  is sized so that drain arm  64  of pick up tube  54  can be inserted into or pulled from channel  82  with a snug but sliding fit. In the industry, this sometimes is referred to as a “press fit.” A suitable fit is indicated when the tube arm  64  slides back and forth within channel  82  with light to moderate hand force manually applied without use of tools, but is snug enough so that the installed tube  54  does not fall out of compressible bushing  66  when pick up tube assembly  52  is shaken by hand prior to being threadably engaged with boss  38 . 
         [0055]    The cross-section of channel  82  may be constant from first end  70  to second end  72  or it may taper from one end to the other, or have some other smooth or undulating contour. More desirably, the cross section of channel  82  gently tapers from first end  70  to second end  72 . By way of example, a suitable taper is in the range from 0.25 degrees to 5 degrees, preferably 0.5 degrees to 3 degrees, most preferably about 1 degree. In those embodiments including a taper, a suitable taper can be established based upon the outside diameter of drain arm  64 . The opening  86  of channel  82  proximal to first end  70  desirably is just slightly larger than the outside diameter of arm  64 . In some embodiments, the opening  86  is 0.003 inches to 0.03 inches, preferably 0.005 to 0.02, more preferably 0.007 to 0.015 inches larger in diameter than the outside diameter of drain arm  64 . For example, in one embodiment, a difference of 0.015 inches was found to be suitable. 
         [0056]    The taper is created by sizing the opening  88  at second end  72  to be equal to or slightly smaller in diameter than the outside diameter of drain arm  64  with an outside diameter of 0.5 inches. In some embodiments, opening  88  is 0.002 to 0.03 inches, preferably 0.003 to 0.01 inches smaller than the outside diameter of drain arm  64  having an outside diameter of 0.5 inches. 
         [0057]    Body  68  is resiliently compressible. Resilient means that body  68  is able to at least partially and more preferentially substantially regain its original shape after being compressed elastically by threadable engagement with bore  38  for 5 minutes at 25° C. and the compression force is then removed by threadably removing body  68  from bore  38 . Exemplary resiliently compressible materials may have one or more desirable characteristics. In some embodiments, a suitable resiliently compressible material has an elongation at break in the range of 100% to 400%, more preferably 200% to 350%, even more preferably 250% to 350% according to DIN 53504 Si. In one mode of practice, an elongation at break of 290% would be suitable. In some embodiments, a suitable resiliently compressible material has a hardness Shore A in the range from 50 to 90, preferably 60 to 80, more preferably 65 to 75 according to DIN 53505. In one mode of practice, a Shore A hardness of 70 would be suitable. In some embodiments, a suitable resiliently compressible material has a rebound elasticity of 55% to 90%, more preferably 65% to 80% according to DIN 53512. In one mode of practice, a rebound elasticity of 71% would be suitable. In some embodiments, a suitable resiliently compressible material has a tensile strength in the range from 5 N/mm 2  to 15 N/mm 2 , preferably 6.5 N/mm 2  to 10.5 N/mm 2  according to DIN 53504 S 1. In one mode of practice, a tensile strength of 8.6 N/mm 2  would be suitable. In some embodiments, a suitable resiliently compressible material has a density in the range from 0.9 g/cm 3  to 1.3 g/cm 3 , preferably 1.0 g/cm 3  to  1 . 2  g/cm 3  according to ISO 1183-1 A. In one mode of practice a density of 1.14 g/cm 3  would be suitable. In some embodiments, a resiliently compressible material has a tear-strength in the range from 15 N/mm to 35 N/mm, preferably 15 N/mm to 25 N/mm according to ASTM D 624 B. In one mode of practice, a tear strength of 21 N/mm would be suitable. An illustrative example of a resiliently compressible material having such characteristics is a silicone rubber having that is commercially available from Wacker Chemie AG under the Elastosil LR 3003/70 AIB trade designation. 
         [0058]    A wide variety of resiliently compressible materials can be used to form body  66  as well as head  78  if desired. Exemplary materials include one or more rubbers, particularly one or more silicone rubbers. Silicone rubbers are elastomeric polymers generally are non-reactive, stable, and resistant to extreme environments and temperatures from −55° C. to +300° C. while still maintaining useful properties. Silicone rubber also is easy to sterilize and therefore is useful in the practice of brewing beer. More preferred embodiments of silicone rubber are suitable for food contact. More preferred silicone rubbers are approved for food contact use according to one or more of FDA Title 21 CFR 178.3292 and/or 21 CFR 166.2600. More preferred silicone rubbers further are approved for food contact use according to European Union (BfR) standards. The silicone rubber optionally may be used in combination with one or more other polymers. Additives also may be incorporated into the formulation to modulate properties. Examples of polymers include polyesters, polyurethanes, polyethers, polyamides, polyimides, fluorinated polymers, polyolefins, combinations of these, and the like. Examples of additives include inert fillers such as TiO 2 , antioxidants, antistatic agents, fungicides, bactericides, heat stabilizers, coloring agents, stain inhibiting agents, plasticizers, stiffening agents, combinations of these and the like. 
         [0059]    The compressible characteristics of body  68  are advantageous. When body  68  threadably engages female threads of bore  38 , channel  82  is compressed over a wide surface area of drain tube arm  64 . As a consequence, body  68  grips drain tube arm  64  tighter to create a fluid tight seal between the two components. At the same time, the threadable engagement compresses male threads  74  against female threads  48  around the surface area of body  68  to create a fluid tight seal between the components. Body  68  thus serves multiple purposes as a way to couple tube  54  to fluid drain coupling  36  and as a gasket for sealing purposes. This avoids the need for separate gaskets. Body  68  grips tube  54  so tightly, that separate coupling components typically used in conventional practices are not needed. Moreover, adjustment of how pick up arm  62  is aimed are easy to implement. Quite simply, body  68  is loosened from bore  38  to reduce the grip of body  68  on tube  54 . This allows drain arm  64  to be rotated to aim pick up arm  62  in any desired direction. The body  64  is then re-tightened to securely grip tube  54  again. This is contrasted to the conventional approaches in which one or more coupling fixtures are involved in order to accomplish a similar adjustment. 
         [0060]    Brew kettle system  10  is easy to set up and use for beer brewing. The components of kettle  12  and pick up tube assembly are cleaned and sterilized as appropriate. Pick up tube  54  is press fit into compressible bushing  66 . Body  68  of bushing  66  is tightened into bore  38  with pick up arm  62  aimed in interior volume  35  as desired. A valve  84  or other suitable closure is closed so that liquid in kettle  12  is not able to drain through pick up tube assembly  52 . The wort formulation is added to kettle  12 , sometimes in stages, and boiled as desired. At the end of boiling, the valve or closure is opened to allow the heated wort to be drained from kettle  12  for subsequent processing. In a typical next stage of processing, the heated wort is optionally filtered and transferred to a cooling stage (not shown) to lower the temperature of the wort prior to downstream stages such as additional flavoring, fermentation, carbonation, etc. 
         [0061]    The present invention has been described above with respect to boiling wort in a kettle system  10 . Principles of the present invention can be practiced in any context where it is desired to drain fluid contents of a vessel via an easily manufactured, easily installed, easily adjusted, and easily used drain structure. For example, in brewing operations, principles of the present invention may be used to install a drain structure in a mash ton or a sparge/hot liquor tank. In chemical manufacturing, the structure can be used on reaction vessels to drain solvents, reaction products, etc. The structures also can be used to feed solvents, reactants, processing aids, etc. into a reaction vessel. The structures also can be used to add and remove solvents in liquid extraction units. The structures can be easily integrated into existing equipment to add fluid feed and fluid drain characteristics to a tank or other vessel. 
         [0062]    All patents, patent applications, and publications cited herein are incorporated by reference as if individually incorporated. Unless otherwise indicated, all parts and percentages are by weight and all molecular weights are number average molecular weights. The foregoing detailed description has been given for clarity of understanding only. No unnecessary limitations are to be understood therefrom. The invention is not limited to the exact details shown and described, for variations obvious to one skilled in the art will be included within the invention defined by the claims.