1. Field of the Invention
This invention relates generally to fermentors, specifically to conical fermentors for homemade beer and wine making
2. Discussion of Prior Art
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.
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.
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.
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.
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.
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.
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.
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.
Accordingly, it is an object of this invention to provide a conical fermentor with pressure capability without welding the lid onto the fermentor.
It is yet another object of the invention to provide an access hatch without welding onto the fermentor.
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.
It is a final object of the invention to provide a completely gas and liquid tight fermentor lid seal.
Further objects and advantages of my invention will become apparent from a consideration of the drawings and ensuring description.
a and
a shows the preferred embodiment of beaded lid seal design.
a shows the preferred embodiment of lid sealing mechanism.
a shows a standard soda keg hatch assembly installed in a standard soda keg top.
Referring to the drawings, and particularly
In an alternate embodiment shown in
An alternate embodiment shown in
Another embodiment shown in
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
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
In the preferred embodiment, shown in
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.
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
Referring to
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.
Alternately, stud 2 can be collared stud 6 as shown in
A lid 21 is sealed against tank lip 27 with seal 20 containing bead 19 as shown in
As shown in
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.
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.
This application is a continuation in part of application Ser. No. 10/873,791, filed Jun. 22, 2004 now abandoned.
Number | Date | Country | |
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Parent | 10873791 | Jun 2004 | US |
Child | 12317555 | US |