Abstract:
An improved homebrewing conical fermentor having pressure capability for CO2 pumping and carbonation, without welding onto the tank, which can lead to contamination of the fermenting product. In addition, the fermentor support legs remain permanently affixed to the tank without introducing any welding flaws on the inside of the tank. A removable access hatch is provided, again without any welding onto the tank lid. A lid seal is provided with a bead that improves sealing capability against the tank lip. Lastly, a removable lid design utilizing a band clam that eliminates the need to weld the lid to the tank and allows for easy access to the interior of the fermentor for cleaning and sanitation.

Description:
[0001]    This application is a continuation in part of application Ser. No. 10/873,791, filed Jun. 22, 2004 now abandoned. 
     
    
     BACKGROUND 
       [0002]    1. Field of the Invention 
         [0003]    This invention relates generally to fermentors, specifically to conical fermentors for homemade beer and wine making 
         [0004]    2. Discussion of Prior Art 
         [0005]    It is well known in the art to utilize a conical bottomed fermentor for fermenting beer or wine. The spent yeast and other fermentation materials settle to the bottom of the cone and can be easily removed by a drain valve located at the bottom of the cone. This eliminates the need to transfer (rack) the beer or wine to another container for secondary fermentation, and avoids the risk of contamination and oxidation. 
         [0006]    Such conical fermentors for commercial breweries also have pressure capability for sanitarily pumping the finished product via CO2 pressure, and for forced carbonation of the finished product. Prior art homebrew fermentors utilize flat lids secured to the top of the fermentor with a clamping foot in the center of the lid. Others use a series of clamps or latches around the perimeter of the lid. Both of these prior art designs do not tolerate pressure due to the flexing of the lid due to uneven or inadequate clamping force and leak gas if pressurized, thereby preventing CO2 pumping or pressure carbonation. 
         [0007]    Due to the large size of commercial fermentors, they are necessarily made from formed sheets of material (usually stainless steel or copper) welded together and carefully ground and polished on the interior to remove pits and other weld flaws which hide bacterial and contaminate the fermenting product. Legs are then welded to the exterior of the fermentor so that it may be set on a floor. Also provided is an access hatch for the adding of hops, finings, and the like, to the fermentor during the fermentation process and also to facilitate cleaning. 
         [0008]    Prior art homebrewing conical fermentors are derivatives of the large commercial fermentors, but are constructed from commercially available “hoppers”. These hoppers are formed from flat stainless sheet, deep-drawn into a pot, and them have a cone spun on the bottom without any welding whatsoever. This eliminates any risk of pitting and flaws associated with welding and the bacterial contamination that can ensue. In addition, the manufacturing costs are substantially lower using this method of manufacture. 
         [0009]    However, affixing mounting legs, even through welded from the outside, leaves unavoidable permanent marking and burn-through pitting due to the comparatively thin walls of these commercially available one-piece drawn and spun tanks. Clamp-on leg designs exist, but are expensive to manufacture and clumsy to install and use. Other designs use a stand that does not remain affixed to the fermentor when moved, or for cleaning which is yet another large disadvantage for a small homebrew sized fermentor which are typically carried and cleaned in a household sink. 
         [0010]    Lid seals for prior art fermentors are typically “U” shaped elastomeric seals that are placed over the edge of the tank lip or lid. Since the surfaces of these tank lips and lids are not perfectly flat, getting a gas and liquid tight seal is difficult and unreliable. Any air infiltration into the fermentor will stale (oxidize) the fermenting product negatively affecting the flavor. 
         [0011]    Providing an access hath in homebrew-sized fermentor is typically done by welding the top of a stainless soda keg onto the top of the fermentor as taught by the Sabco Company. However, this welding process can leave weld flaws and the associated problems of contamination, In addition, this is a costly method to provide this feature. 
         [0012]    Finally, providing pressure capability without welding the lid onto the tank is unavoidable in prior art fermentors due to structural pressure limitations, making cleaning the small homebrewing fermentor very cumbersome since internal surfaces are difficult or impossible to reach. 
       OBJECTS AND ADVANTAGES 
       [0013]    Accordingly, it is an object of this invention to provide a conical fermentor with pressure capability without welding the lid onto the fermentor. 
         [0014]    It is yet another object of the invention to provide an access hatch without welding onto the fermentor. 
         [0015]    It is yet another object of this invention to provide a fermentor leg design that remains affixed to the fermentor for ease of cleaning and portability, but does not leave weld flaws on the interior of the fermentor. 
         [0016]    It is a final object of the invention to provide a completely gas and liquid tight fermentor lid seal. 
         [0017]    Further objects and advantages of my invention will become apparent from a consideration of the drawings and ensuring description. 
     
    
     
       DESCRIPTION OF DRAWINGS 
         [0018]      FIG. 1   a  and  FIG. 1   b  show a side cut-away and top view of a preferred embodiment of fermentor leg assembly, the fermentor being generally circular in configuration.  FIG. 2   a  shows an alternative embodiment where a nut is used in lieu of a spacing collar.  FIG. 2   b  shows an alternate embodiment where a collared stud is utilized in lieu of a spacing collar.  FIG. 2   c  shows an alternate embodiment where an internally threaded standoff is utilized in lieu of a spacing collar.  FIG. 2   d  shows and alternate embodiment where legs contain mounting flanges and leg is directly bolted to tank without spacers, collars of backing nuts. 
           [0019]      FIG. 3   a  shows the preferred embodiment of beaded lid seal design.  FIG. 3   b  shows and alternate embodiment of lid seal where bead is replaced with an edge-type design.  FIG. 3   c  shows an alternate embodiment of lid seal where bead is replaced with a wiper-type design. 
           [0020]      FIG. 4   a  shows the preferred embodiment of lid sealing mechanism.  FIG. 4   b  shows an alternate embodiment where a clamp ring is used to reduce seal buckling when tightening.  FIG. 4   c  shows and alternate embodiment where tank lip is a beaded design.  FIG. 4   d  shows and alternate embodiment where a support ring is utilized to hold the seal properly in place and reduce seal bunching when tightening. 
           [0021]      FIG. 5   a  shows a standard soda keg hatch assembly installed in a standard soda keg top.  FIG. 5   b  shows standard soda keg hatch assembly with shortened legs installed on a flat lid thereby reducing manufacturing and tooling costs.  FIG. 5   c  shows an alternate embodiment whereby stamped soda keg hatch lip profile is stamped directly onto the lid, thereby eliminating the need to shorten the hatch legs. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0022]    Referring to the drawings, and particularly  FIGS. 1   a  and  FIG. 1   b , a generally circular tank  1  is fitted with at least one capacitive discharge (CD) or arc studs  2 . In the preferred embodiment, shown in  FIG. 1   a  and  FIG. 1   b , a spacer  11  is placed over stud  2  to allow for full bolt torque. Leg  5 , having appropriately placed mounting holes  13 , is placed over studs  2  and fastened to tank  1  with nuts  4 . At least three legs  5 , are installed on tank  1 , preferably 120 degrees apart for optimum stability. 
         [0023]    In an alternate embodiment shown in  FIG. 2   a , a backing nut  12  is placed on stud  2  to the appropriate height. Leg  5  is then installed over studs  2  and secured with nut  4 . 
         [0024]    An alternate embodiment shown in  FIG. 2   b  utilizes a collared stud  6 , eliminating the need for spacer  3 . 
         [0025]    Another embodiment shown in  FIG. 2   c  utilizes an internally threaded stand-off  7  in lieu of stud  2  and utilizes a cap screw  8  to affix leg  5  to tank  1 . Internally threaded stand-off  7  eliminates the need for spacer  3  or collar on stud  6 . Yet another embodiment shown in  FIG. 2   d  utilizes a leg  9  with flanges  10  whereby studs  2  affix the leg to tank  1 . Further embodiments not shown in the drawings include tubes, bars, “H” sections etc. 
         [0026]      FIG. 3   a  shows a seal  20  with a bead  19  and a cavity  45  to receive lip of tank lid  21  or tank lip  27 . The tank  1  is formed from a plate in a spin forming operation. The plate has a preestablished thickness enabling the spinning operation to be operable. The tank  1  is conical and defines a bottom portion  50  and has an opening  52  therein being positioned opposite the bottom portion  50 . The tank lip  27  extends from the opening  52 . The tank lip  27  has a cylindrical configuration and defines an outer diameter  54  and an inner diameter  56 . A radius is interposed the tank lip  27  and the bottom portion  50 . The outer diameter is spaced from the inner diameter a preestablished distance. The preestablished distance is determined by the sum of the radius and a flat portion  58 . In this application, the radius is about 15 mm and the preestablished distance is about 30 mm. Thus, the flat portion  58  also has a distance being equivalent to about 15 mm. The flat portion  58  defines a first surface  60  and a first sealing surface  62  along the flat portion  58  being position parallel and opposite one another by the thickness of the plate. The tank lid  21  has an outer diameter  70  being larger than the inner diameter  56  of the tank lip  21 . In this application, the outer diameter of the tank lid  21  is smaller than the outer diameter  54  of the tank lip. The tank lid  21  is formed from a plate having a first side  72  and a second side  74 . At least one of the first side  72  and the second side  74  has a sealing surface  76  thereon. The sealing surface  76  extends from the outer diameter  70  toward the inner diameter  56  of the tank lip  21  a preestablished distance. In this application, the preestablished distance of the sealing surface  76  is about 20 mm. Ideally, the flat portion  58  of the tank lip  27  and the sealing surface  76  of the tank lid  21  are flat. However, it is contemplated that the flatness of flat portion  58  and the sealing surface  76  can have between a 5 and 10 degrees variation due to manufacturing tolerances. Thus, the need for the seal  20 . The cavity  45  is formed by a base  46  having a pair of legs  48  extending from the base  46  a preestablished distance. In this application, the preestablished distance of the pair of legs  48  is less than the preestablished distance of the flat portion  58  of the tank lip  27 . The seal  20  is preferably constructed of a flexible elastomeric material. Seal  20  has a first sealing surface  80  and a second sealing surface  82  being utilized to provide a gas and liquid tight seal against tank lip  27  and lid  21 . Bead  19  and seal  20  experiences a high localized pressure from a lid clamping force  24  and as a result deforms and creates a positive seal against tank lip  27  alternately, bead  19  can be shaped into numerous profiles such as edge  18  as shown in  FIG. 3   b  and wiper  17  as shown in  FIG. 3   c.    
         [0027]      FIGS. 4   a - d  shows alternate methods to seal lid  21  against tank lip  27  using a band clamp  25  and seal  20  (shown without bead  19 ). The band clamp  25  has a preestablished open size and a preestablished closed size and can be tightened therebetween. The band clamp  25  has a cross-section defining a base portion  90  having a pair of legs  92  extending therefrom at an angle. In this application, the angle of each of the pair of legs  92  to the base portion  90  is about 30 degrees. However, it is contemplated that the angle could be between 15 and 45 degrees and functionally performs the clamping operation. Each of the pair of legs  92  defining a wedging surface  94  being in wedging relationship with one of the tank lip  21  and tank lid  27 , and the seal  20 . For example in operation as shown in  FIG. 4   a , the wedging surface  94  of one of the pair of legs  92  is in contacting relationship with the seal  20  and the first surface  60  of the tank lip  27 . And, in operation as shown in  FIG. 4   d , the wedging surface  94  of one of the pair of legs  92  is in contacting relationship with the first surface  60  of the tank lip  27  and the wedging surface  94  of the other of the pair of leg  92  is in contacting relationship with the first side  72  of the tank lid  21 . 
         [0028]    In the preferred embodiment, shown in  FIG. 4   a , band clamp  25  provides clamping force  24  when tightened.  FIG. 4   b  shows a clamp ring  26  preferably made from steel or hard plastic, which allows band clamp  25  to tighten with reduced bunching of seal  20 .  FIG. 4   c  shows a beaded lid lip  28  on tank  1 .  FIG. 4   d  shows yet another embodiment utilizing a seal support ring  29  that supports seal  20  during tightening of band clamp  25 . Obviously, many combinations of similar band clamp assembly designs could be conceived, such as placing seal  20  on the lip of tank  1  instead of lid  21 . 
         [0029]      FIG. 5   a  shows a standard soda keg hatch assembly  32  installed in a standard soda keg top  39 . A pair of hatch legs  33  on a handle assemble  38  is rotatably affixed about a hinge point  40 . A hatch seal  34  is placed between lid assembly  32  and soda keg top  39 . 
         [0030]      FIG. 5   b  shows the preferred embodiment of the invention where hatch legs  33  are shortened to allow lid  21  with a flat sealing surface  41  to be utilized in lieu of a stamped soda keg hatch lip  37  in soda keg top  30  having a form-fitting profile as shown in  FIG. 5   a . Alternately, lid  21  can be manufactured with a standard soda keg hatch lip  37  as an integral part of the lid as shown in  FIG. 5   c , thereby eliminating the need to shorten hatch legs  33 . 
       OPERATIONS OF THE PREFERRED EMBODIMENT 
       [0031]    Referring to  FIGS. 1   a  and  1   b , stud  2  is welded to tank wall  1  utilizing a typical capacitive discharge or arc stud welding process. This welding process is ideally suited to welding studs and stand-offs to thin sheet steel leaving absolutely no marking or the opposite side of the sheet. Due to the extremely short arch duration of a CD or acc stud welding machine, the energy is concentrated in a very small area resulting in a strong weld and small heat affected zone. Since the interior side (opposite the stud) of the sheet is not heated substantially, there is absolutely no risk of burn through or pitting and through associated contamination issues. Yet the weld is permanent and very strong. In the preferred embodiment, spacer  3  is placed over stud  2 . Leg  5  is then installed over stud  2  and nut  4  compresses leg  2  into spacer  3 , spacer  3  enabling full bolt torque. Although spacer  3  could be eliminated, full bolt torque cannot be applied resulting in an unsatisfactory, unsafe bolted joint design. 
         [0032]    In an alternate embodiment, stud backing nut  12  is placed on stud  2  to the height dictated by leg  5  so legs rest against tank wall  1 . Leg  5  is placed over stud  2  and fastened with nut  4 , securing leg  5  to tank  1  with proper full bolt torque. 
         [0033]    Alternately, stud  2  can be collared stud  6  as shown in  FIG. 2   a  where collar on stud  6  allows for full bolt torque. In yet another embodiment, a threaded standoff  7  is welded to tank  1  and cap screw  8  affixes leg  5  to the tank allowing for proper bolt torque. In another embodiment, shown in  FIG. 2   d , leg  9  is manufactured with flange  10 . Flange  10  is held to tank  1  with stud  2  and nut  4 . Obviously, many possible ramifications could be conceived utilizing tubes, 14 channels, bars, and the like in conjunction with the various variety of CD or arc weld fittings commercially available or custom manufactured to affix a leg to the fermentor. 
         [0034]    A lid  21  is sealed against tank lip  27  with seal  20  containing bead  19  as shown in  FIG. 3   a . Cavity  45  of seal  20  is placed over lid  21 . Alternately, cavity  45  can be placed over tank lip  27 . As lid clamping force  24  is applied to lid  21  bead  19  experiences a high localized pressure and forms tightly against tank lip  27  creating a gas and liquid tight seal. Lid clamping force  24  can be from a multiple sources including, but not limited to, a pressure foot, drawn latch, toggle clamp, or similar prior art means. Bead  19  can be many alternate shapes such as edge  18  shown in  FIG. 3   b , and wiper  17  shown in  FIG. 3   c.    
         [0035]    As shown in  FIG. 4   a , clamp force  24  can be provided by a band clamp  25  placed over seal  20  and tank lip  27  encapsulating lip  21 . Since typical band clamps provide high sealing forces, bead  19  is not required to function properly.  FIG. 4   b  shows clamping ring  26 , which prevents seal  20  from bunching during tightening.  FIG. 4   c  shows an alternate beaded tank lip  28 .  FIG. 4   d  shows a seal support ring  29  used to support seal  20  when band clamp  25  is tightened. Obviously, band clamp  24  can be numerous shapes such as “V” shaped, “U” shaped, or many other common configurations. 
         [0036]      FIG. 5   a  shows a standard soda keg hatch assembly  32  installed in a standard soda keg top  39 . Since these lids are mass produced they are very cost effective and ideally suited for a homebrew sized fermentor access hatch. A pair of hatch legs  33  on handle assembly  38  is rotatably affixed about a hinge point  40 . A hatch seal  34  is placed between lid assembly  32  and soda keg top  39 . When handle assembly  38  is rotated about hinge pint  40 , hatch legs  33  drive standard soda keg hatch assembly  32  upward thereby compressing hatch seal  34  creating a gas and liquid tight seal.  FIG. 5   b  shows the preferred embodiment of the invention where legs  33  are shortened to compensate for the elimination of stamped soda keg hatch lip  37  in soda keg top  39  as shown in  FIG. 5   a . This allows for a simpler flat lid sealing surface  41  eliminating expensive stamping tooling or secondary manufacturing operations. Alternately, lid  21  can be manufactured with a standard soda keg hatch lip  37  profile stamped into it as an integral part of the lid as shown in  FIG. 5   c , thereby eliminating the need to shorten hatch legs  33 . Depending on intended design pressure, it may be necessary to form the remaining surfaces of the lid into a dome shape to reduce lip flexing. 
       SUMMARY, RAMIFICATIONS, AND SCOPE 
       [0037]    Thus the reader will see that the improved conical fermentor provides the homebrewer with all the features of a commercial conical fermentor but does so without any chance of introducing welding flaws in the interior of the fermentor. While my description contains many specificities, these should not be construed a limitations of the scope of the invention, but rather as and exemplification of one preferred embodiment thereof. Many other variations of lid seal profiles, band clamp profiles, leg shapes, and leg clamping configurations are obviously possible. Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents.