Patent Application
20070041269
The present invention relates generally to mixing apparatuses and methods. More particularly, the present invention relates to an apparatus and method of magnetically mixing and/or agitating substances.
Many industries, such as the chemical and pharmaceutical industries, require mixing of substances (e.g., chemicals) in extremely clean environments. In order to meet the requirements of these industries, specially-designed mixing tanks and stirring mechanisms have been developed.
Substances in many of the above-mentioned tanks are discharged from the tanks by being allowed to flow through openings located at or near the bottom of the tanks. Therefore, in order to promote homogeneity of the flows coming out of the tanks, the stirring mechanisms are typically located at the bottom of the tanks.
One currently-available stirring mechanism has a first portion thereof (i.e., an exterior portion) configured to be positioned on the outside of a tank and a second portion (i.e., an interior portion) configured to be positioned on the inside of the tank. Each of the interior portion and the exterior portion have magnets included therein.
The interior portion includes a cavity and, when positioned inside of the tank, the cavity accommodates the insertion therein of a raised feature on the bottom surface of the tank. Because the thickness of the tank is substantially uniform, the raised feature inside of the tank has an associated indentation on the outside of the tank. When the indentation has dimensions that allow for the interior portion to be inserted into the indentation, the interior portion may be magnetically coupled to the exterior portion through the tank wall at the location of the indentation.
In operation, once the exterior portion is positioned in the indentation and the raised feature is inserted into the cavity of the interior portion, the exterior portion is rotated about a fixed axis by a motor and a set of gears that are positioned outside of the tank and that are connected to the exterior portion. Because of the magnetic coupling between the interior portion and the exterior portion, as the exterior portion is rotated, the interior portion, which has a set of blades attached thereto, is also rotated. As the interior portion and blades are rotated, the set of blades agitates and/or mixes the substances at the bottom of the tank and a degree of homogeneity is achieved locally at the bottom of the tank.
Because the blades are positioned adjacent to the bottom of the tank, very little fluid flow is possible between the blades and the bottom of the tank. In other words, very little exhaust flow is possible below the bottom of the blades. Therefore, the above-discussed mixing tank is only relatively successful at homogenizing substances at the bottom of a tank.
In addition to the above, because the blades are positioned adjacent to the bottom of the tank, substances at the top of the tank are oftentimes too far away from the blades to be substantially agitated or mixed by the blades. Therefore, the likelihood of achieving a homogeneous mixture throughout the tank using the above-discussed mixing tank is even further reduced. At least in view of the above factors, the composition of substances flowing out of the tank when the tank is relatively full may differ from the composition of substances flowing out of the tank when the tank is relatively empty due, which is an undesirable condition.
Also, the presence of an indentation at the bottom of the tank and the need to position the second portion relative to the indentation makes insertion of the stirring mechanism relatively difficult, particularly in relatively tall tanks. Further, the presence of the indentation makes the tank more difficult to clean than smooth-bottomed tanks.
Accordingly, there is a need in the art to provide an apparatus and method for mixing, agitating or stirring substances that are configured to promote substantial homogeneity throughout a tank. Further, there is a need in the art for such mixing, agitating or stirring apparatuses that may be more easily inserted and removed from a tank, so that the tank may be easily cleaned. Even further, there is a need in the art to provide a mixing apparatus and method for mixing substances that minimize friction and wear, thereby reducing the amount of particulates that get released into a tank during mixing.
The foregoing needs are met, to a great extent, by certain embodiments of the present invention, wherein in one embodiment a stirring apparatus is provided. The stirring apparatus includes a coupling member that includes a magnet. The stirring apparatus also includes an extension connected to the coupling member. Further, the stirring apparatus includes an impeller connected to the extension at a location remote to the coupling member. In addition, the stirring apparatus includes a support connected to at least one of the coupling member, the extension or the impeller.
According to another embodiment of the present invention, another stirring apparatus is provided. The stirring apparatus includes a tank and a first coupling member positioned inside the tank, wherein the first coupling member includes a first magnet. The stirring apparatus also includes a second coupling member positioned outside the tank, wherein the second coupling member includes a second magnet. The stirring apparatus further includes an extension connected to the first coupling member. In addition, the stirring apparatus includes an impeller connected to the extension, wherein the impeller includes a plurality of blades. Further, the stirring apparatus includes a support connected to the extension, wherein the support includes a first leg, a second leg and a third leg.
According to yet another embodiment of the present invention, a method of stirring a substance in a tank is provided. The method includes rotating a first coupling member positioned inside of a tank using a force exerted by a second coupling member positioned outside of the tank. The method also included rotating an impeller using the first coupling member, wherein the impeller is connected to the first coupling member at a location remote to the first coupling member. The method further includes stabilizing the impeller using a support that is detached from the tank.
In accordance with still another embodiment of the present invention, another stirring apparatus is provided. This stirring apparatus includes means for magnetically rotating a coupling member positioned inside of a tank. The stirring apparatus also includes means for separating an impeller from the coupling member and for connecting the impeller and the coupling member. In addition, the stirring apparatus includes means for stabilizing the impeller, wherein the means for stabilizing means is detached from the tank.
There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Various preferred embodiments of the present invention provide for a magnetic mixing apparatus and method for mixing, agitating or mixing substances or the like. At least in view of the above shortcomings of the prior art, novel devices, systems and methods have been developed to stir substances in tanks. Certain embodiments of the present invention will now be described with reference to the drawing figures, in which like reference numbers refer to like parts throughout.
According to certain embodiments of the present invention, the stirring apparatus 10 is positioned at the bottom of a tank and is used to mix, stir or agitate substances in the tank. For example, during operation, the coupling member 12 is positioned either directly adjacent to or in close proximity with the bottom surface of a tank. Also, the coupling member 12 includes one or more magnets that may either be incorporated into the structure of the coupling member 12 or that may be attached to the coupling member 12.
As mentioned above and depicted in
The extension 14 is illustrated in FIG. I as a cylindrical shaft extending generally perpendicular from the top surface of the coupling member 12. However, extensions 14 with alternate geometries and that do not extend perpendicular from the top surface of the coupling member 12 are also within the scope of the embodiments of the present invention. For example, extensions 14 having square, oval or octagonal cross-sections may also be used.
According to certain embodiments of the present invention, in order to facilitate the turnover of substances at the bottom of the tank and to promote homogeneity of substances throughout the tank, the extension 14 has a length equal to approximately ½ of the diameter of the impeller 16. According to these embodiments, if the impeller 16 were to be designed to have a diameter of 24 inches, the extension 14 would be designed to measure approximately 12 inches. Such a configuration promotes not only flow of substances above the impeller 16 but also facilitates exhaust flow below the impeller 16. However, extensions 14 having alternate lengths are also within the scope of the present invention. For example, the extension may have a length equal to approximately ½, ⅔ or ¾ of the height of the tank.
As mentioned above in connection with
The impeller 16 as illustrated in FIG. I includes three blades 18, each positioned at a non-parallel angle relative to the top surface 13 of the coupling member 12. Alternatively, one or more of the blades 18 may be positioned perpendicularly relative to the top surface of the coupling member 12. Also, more or less than three blades 18 may be used.
As illustrated in
Two sets of bearings 20 are illustrated in
The support 22 illustrated in FIG. I is a tripod having a first, second and third leg that are each connected to each other. However, alternative embodiments of the support may include more or less than three legs. Also, the support 22 may be of any geometric configuration that prevents or at least hinders the stirring apparatus 10 from tipping over relative to the bottom surface of a tank in which the stirring apparatus 10 is included.
As illustrated in
The extraction facilitating component 24 typically provides a location on the stirring apparatus 10 that can be conveniently engaged by an extraction tool. For example, the extraction facilitating component 24 may be designed to accommodate the passing of a hook therethrough. In such instances, if the hook is connected to a pole that is long enough to reach the bottom of the tank, a technician at the top of the tank may pull the stirring apparatus 10 out of the tank using the hook. This allows for removal of the stirring apparatus 10 without a technician entering the tank, reducing the likelihood of tank contamination.
Preventing tank contamination is particularly important with respect to relatively large tanks which can be used with the stirring apparatuses. For example, in 1,000-gallon or a 5,000-gallon tanks where the stirring apparatus 10 may be positioned ten feet or further away from a hatch at the top of the tank, it is particularly desirable to allow a technician to remove the stirring apparatus 10 without entering the tank.
The portion of the stirring apparatus 26 illustrated in
As illustrated in
Although only two blades 34 are illustrated in
As illustrated in
As mentioned above, the portion of the stirring apparatus 26 illustrated in
The portion of the stirring apparatus 42 illustrated in
The coupling member 44 includes a plurality of magnets 50 and a plurality of blades 52 that are connected to the coupling member. Although only four magnets and two blades are illustrated in
As illustrated in
During operation of a mixing apparatus that includes the portion 42 illustrated in
When the portion of the stirring apparatus 42 illustrated in
The rotating step 60 also includes applying a magnetic field to rotate the coupling member. This step may be implemented, for example, by rotating or spinning the exterior coupling member 56 illustrated in
As illustrated in
Step 64 comprises stabilizing the impeller using a support that is detached from the tank. This step of stabilization may be accomplished using a support such as, for example, the support 22 illustrated in
Step 66 comprises preventing the support from rotating within the tank. Preventing step 66 may be implemented, for example, by providing components inside of the tank that abut one or more legs of the support and thereby prevent the rotation thereof. Also, indentations that accommodate entry of a portion of the legs of the support may be used to implement step 66.
Step 68 comprises removing the support from the tank through a top opening of the tank. According to certain embodiments of the present invention, a hook can be attached to a portion of the support, impeller, or coupling member to lift the stirring apparatus out of the tank. In alternative embodiments, an extraction facilitating component can be provided that more easily interfaces with an extraction device.
The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
