Abstract:
A mounting and coupling assembly for a mixer for in a container having an impeller connected to a drive shaft, in an assembly, which extends through an opening into the container. The assembly includes a lip mount to stabilize and support the mixer on the lip of said container. A cover secures said lip mount with threaded fasteners engaging complementary fasteners on the container neck and clamping the plate to the container lip. A primary objective of the invention is to allow the stable mounting of a mixing unit to bulk containers and allow easy and safe coupling of a power module to the mixing assembly.

Description:
This application is a continuation-in-part of U.S. patent application Ser. No. 10/730,062 and claims the benefit of U.S. Provisional Application No. 60/431,688 filed Dec. 9, 2002, which are hereby incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to fluid mixing units. More particularly, the present invention relates to apparatus employed in conjunction with containers for agitating, mixing and/or blending of fluids. Yet more particularly, the present invention relates to an assembly for fluid mixing units wherein a mixing assembly is affixed to a container for fluids. 
     BACKGROUND 
     Many industries transport, store, mix, process and/or discharge fluids from commercial bulk containers made of plastic or metal, commonly known in the trade as “tote boxes”, “bulk containers”, or “intermediate bulk containers” (all herein referred to as “containers”). It is often desirable, and in some cases required, that the fluids stored in such containers be agitated, mixed or blended between the time they are loaded into the containers and the time they are discharged therefrom. To affect the desired mixing, according to the prior art, it was necessary to open the container and insert a mixing unit with impeller blades. There are, however, several drawbacks to this approach. 
     A first disadvantage of mixing assemblies used in the art is that as a plurality of containers are usually stored in close proximity, it may be difficult to access the selected container to remove the cover of the access opening or port and to insert the mixing unit. Even if the cover of the opening is readily accessible, it may be difficult to remove the cover, particularly if the material in the container is highly volatile and the lid or port had been sealed to retain vapors. 
     Furthermore, the diameter of the access opening through which the mixing unit is inserted must be of sufficient diameter to allow the insertion of the impeller blades. In addition, if the container is substantially full, the mixing assembly has to be operated with considerable care so as not to splash, or otherwise spill, the contents of the container. This often requires operating the mixing assembly at speeds and power settings insufficient to properly agitate or mix the contents of the container. 
     Mixing units, including the drives and impellers (which are usually a single unit), are usually used with multiple containers and require extensive cleaning each time they are moved from one container to another. At present the containers and mixing units are cleaned after each use, resulting in high costs (both environmentally and in equipment/manpower). For many fluids used in the paint, chemical, and pharmaceutical industries the slightest contaminant left from ineffective cleaning may ruin the fluids in the container. Further substantial costs are also incurred through the expense of using and disposing of cleaning agents such as solvents. Finally, there is a manpower cost in the amount of time required to open, mix, close and seal each container. 
     Another mount for mixing units in the prior art is a bridge mounting that supports the mixing unit above the vessel neck. These mounts also do not seal the container completely thereby allowing contaminants to enter the container. 
     Another solution in the prior art is the use of fully enclosed mixing units within stainless steel bulk containers. Unlike plastic containers, steel containers require extensive and often imperfect cleaning after each use which may contaminate the container contents. The use and disposal of powerful solvents and cleaning agents also create a large cost. 
     Another solution in the prior art is to support mixers by the use of expensive threaded metal lids for mounting the mixer. These lids rely on the threads of the neck and collar of the container to support the loads applied during mixing and often result in cracking of the bulk container and failure of the mount. 
     Yet another method of mixer support is a clamping device positioned around the neck of the container. This may cause difficulties as the clamping shoe inside the housing may collapse the neck of the container. Alternatively, this mount may also rotate on the neck of the container. 
     What is needed is an assembly that seals the container, and does not require any additional support means other than the container itself. Additionally what is needed is a power module that can be detachably secured to the container and mixing assembly. 
     SUMMARY OF THE INVENTION 
     According to the invention, a mounting assembly for a container with a lip is provided, comprising a rigid lip mount shaped to fit on top of said lip, said lip mount defining an aperture shaped to engage a housing for a shaft; a cover for the container, said cover shaped to secure said lip mount to the lip by threadably engaging with the neck, said cover defining an aperture shaped to allow passage of said housing; and mixing means comprising a shaft with a housing, a motor and an impeller. This assembly provides a fully enclosed mixing mount for use inside the container. The lip mount allows for mixing in the container while preserving the integrity of the container (when compared to a threaded metal lid mount), and for a low cost (when compared to a stainless steel bulk container, or the recycling process involved in prior art mixing assemblies). It is, therefore, a primary object of the present invention to provide a mixing assembly, which facilitates agitating, mixing and/or blending of fluids that are shipped and stored in containers. 
     Another object of the present invention is to provide a mixing unit, which permits a mixing assembly to be easily, and if desired, permanently, affixed to a container and that is readily accessible for operation by a power module that can be detachably secured to the mixing assembly. 
     It is yet another object of the present invention to provide a mixing assembly, as above, that allows the power module to be detachably secured to the mixing assembly such that there is no need for a person securing said power module to use tools, or to insert his or her hands in an area where injury could result. 
     It is yet a further object of the present invention to provide a mixing assembly that employs a locking means to prevent inadvertent disengagement of a fast make/break connector. 
     It is a still further object of the present invention to provide a mixing unit, as above, wherein the mixing assembly, when affixed to a container, presents a low profile so that it does not interfere with stacking of the containers. 
     In general, a mixing unit embodying the concepts of the present invention is adapted for use in conjunction with “tote vessel” containers or other containers of the type employed to store, mix and/or discharge fluids. 
     A mixing assembly may be relatively permanently affixed to such a container. The mixing assembly comprises a housing and an impeller shaft rotatably mounted within the bearing housing. One or more impellers are secured to the shaft and disposed interiorly in the container for rotation. 
     A fluid mixing unit embodying the concepts of the present invention is shown by way of example in the accompanying drawings and described in detail without attempting to show all of the various forms and modifications in which the invention might be embodied; the invention being measured by the appended claims and not by the details of the specification. 
     These and other objects of the invention, as well as the advantages thereof over existing and prior art forms, which will be apparent in view of the following detailed specification, are accomplished by means hereinafter described and claimed. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1   a  is a side cross-sectional view of a first embodiment of an assembly according to the invention; 
         FIG. 1   b  is a side cross-sectional view of a second embodiment of an assembly according to the invention; 
         FIG. 2   a  is an exploded side view of the first embodiment; 
         FIG. 2   b  is an exploded side view of the second embodiment; 
         FIG. 3   a  is an exploded perspective view of the first embodiment; 
         FIG. 3   b  is an exploded perspective view of the second embodiment; 
         FIGS. 4   a  and  4   b  are side and bottom views, respectively of a cover therefor; 
         FIG. 5  is an exploded perspective view of a portion of the second embodiment of the assembly; 
         FIG. 6  is a perspective view of the coupling assembly prior to contact; and 
         FIG. 7  is a perspective view of the coupling assembly secured to the coupling member. 
     
    
    
     DETAILED DESCRIPTION 
     As seen in  FIG. 1   a , a first embodiment of the invention is an assembly, generally indicated as  10 , for mounting mixing means to a container  6   b . Mixing means may be of any kind found in the art, and generally comprise drive  1  or other propulsion device, a rotatable shaft  5 , a housing  4  surrounding at least the upper portion of shaft  5 , and impellers to mix the contents of container  6   b . In this document, the terms “mixer” and “mixing means” will be used interchangeably. Container  6   b  is preferably made of plastic or steel, and may be any one of the many bulk containers available in the art. Container  6   b  is made to hold large amounts of material, usually fluids. The invention uses a lip mount  3  to stabilize and support the mixer on the lip  6  of container  6   b . Lip mount  3  is generally disc shaped as best seen in  FIG. 5  and is preferably made of a hard rigid material such as metal that can distribute the weight of the mixing means. Lip mount  3 , when in position on lip  6 , acts as a support for the mixer inserted through lip mount  3  into container  6   b . Lip mount  3  preferably has a circumference equal to the outside diameter of lip  6  of neck  6   a  of container  6   b  such that lip mount  3  can rest on top of lip  6 . Lip mount  3  may have an aperture sized to receive threaded mixer housing  4 . Alternatively, housing  4  may be secured to lip mount  3  by welding or other securing means known in the art. 
     In a preferred embodiment of the invention, a gasket  3   b  is preferably secured by glue or other conventional means to the edge  3   a  of the underside of lip mount  3 . Gasket  3   b  is positioned to engage the outer side of neck lip  6  to provide further support for lip mount  3 . Lip mount  3  is positioned between the lip  6  of the cylindrical neck  6   a  of container  6   b . Neck  6   a  has external screw threads, and receives cover  2 , allowing cover  2  to act as a collar. Cover  2  secures lip mount  3  by engaging the threaded fasteners on the container neck  6   a  to hold lip mount  3  into position. 
     As best seen in  FIG. 2   a , neck  6   a  extends from container  6   b , and ends at lip  6 . Mixer shaft  5  is inserted though neck  6   a  of container  6   b  to reach the interior of container  6   b . The top of shaft  5  and housing  4  are supported and sealed in container  6   b  by lip mount  3 , which allows the mixer assembly to rest on the cover  2  of the container  6   b . Housing  4  is secured to lip mount  3  by securing means. In an alternative embodiment of the invention, lip mount  3  and housing  4  may be welded or manufactured in a single piece. 
     In a preferred embodiment, cover  2  threadably engages neck  6   a  and may be screwed on to neck  6   a  to compress lip mount  3  into place. Cover  2  may be included as part of the mixer and inserted above lip mount  3  and below mixer drive  1 . This complete assembly may then be inserted into and onto lip  6  allowing cover  2  to be engaged as above. 
     As seen in  FIG. 3   a , housing  4  is engaged with lip mount  3  allowing shaft  5  to extend downwardly into container  6   b . The bottom portion of mixer drive  1  couples with the top portion of housing  4 , but lip mount  3  prevents mixer drive  1  from passing further into container  6   b . In an alternative embodiment, housing  4  and lip mount  3  may be a single piece. 
     An embodiment of the invention includes an assembly for agitating, mixing and/or blending fluids affixed to container  6   b  using lip mount  3 . Lip mount  3  is compressed between threaded container neck  6  and a threaded cover  2 . The positioning of lip mount  3  between the container lip  6  and cover  2  causes the mixer  1  to be supported by the combined structure of both cover  2  and lip  6 . 
     Shaft  5  is rotatably mounted in housing  4  to rotate an impeller secured to shaft  5 . This impeller is sealed within the interior of the container  6   b.    
     The assembly also preferably includes a power module that is detachably secured to the mixing assembly by coupling assembly, generally indicated as  100 , as seen in  FIGS. 6 and 7 . A preferred embodiment of coupling assembly  100  includes coupling member  20 , as best seen in  FIG. 6 , positioned at the top of shaft  5 , with coupling pin  24  positioned horizontally thereto. Drive shaft  28  of motor  1  extends downwardly therefrom and at its bottom end is shaft coupling member  32 . Shaft coupling member  32  has groove  36  for receiving coupling pin  24 . 
     Sheath  48  extends downwardly from motor  1  encompassing shaft coupling member  32 . Sheath  48  is shaped to cover shaft coupling member  32 . Sheath coupling member  52  is sized to receive sheath  48  and cover shaft coupling member  32 . Sheath coupling member  52  preferably extends cylindrically from housing  4 . Alternatively, sheath coupling member  52  may extend cylindrically from lip mount  3 . 
     Sheath  48 , as best seen in  FIG. 7 , has an L-shaped groove  56  to receive pin  44 . When sheath coupling member  52  is secured to sheath  48  by pin  44  and groove  56 , during operation of the mixing assembly  10 , the rotation of drive shaft  28  assists in locking pin  44  with groove  56 . 
     Sheath coupling member  52  is secured to housing  4  by securing means or may be part of housing means  4 . In a preferred embodiment of the invention, the parts described above are easily replaceable and may be substituted should they become worn, or should an alternative securing means be used. 
     In use shaft coupling member  32  is lowered onto coupling member  20  such that coupling pin  24  is received by groove  36 , as seen in  FIG. 7 . Pin  44  is simultaneously inserted into groove  56  to hold shaft coupling member  32  to shaft  5 . Sheath  48  engages sheath coupling member  52  such that pin  44  is engaged by groove  56 . Sheath  48  is then turned and groove  56  locks pin  44  in place thereby securing sheath  48  to sheath coupling member  52 . When the agitator is operated to mix the liquid the drive motor  1  module drives agitator shaft  5 . 
     An alternative embodiment of coupling assembly  100  (not shown), includes locking studs positioned on a mounting plate secured to the top surface of a lid to secure drive  1  to the lid. In this embodiment, the lid is used instead of cover  2 . The lid has a generally flat cylindrical shape as is sized to cover the opening of the tote. A flange circumferentially extends from the bottom of sheath  48 . This flange includes apertures to receive the locking studs on the mounting plate. After receiving the studs through the apertures, drive  1  can be rotated slightly allowing the studs to move to a smaller portion of the aperture to lock the studs in place on the mounting plate. The studs can then be tightened by nuts or the like, to further secure the flange to the mounting plate. Alternatively, rather than using a mounting plate, the studs can be part of the lid, allowing the flanges to be secured directly to the lid. 
     In an alternative embodiment of the invention as seen in  FIGS. 1   b ,  2   b , and  3   b  no gasket is used. Instead the underside  8   b  of lip mount  3  may be padded to help it secure to lip  6 . In yet another alternative embodiment, lip mount  3  may be molded to a particular shape to increase the ability to better handle pressure and to help secure lip mount  3  to lip  6 . 
     As best seen in  FIGS. 4   a  and  4   b  cover  2  is a standard cover for use with containers in the field. However, cover  2  has an aperture through which the bottom portion of mixer drive  1  and shaft  4  can pass. The assembly according to the invention positions the mixer in the center of cover  2  (as part of the cover) so that cover  2  can be rotated around the mixer, clamping the assembly into place. 
     As the cover is sealed, the contents may be pressurized and maintained under pressure as the mixing assembly is operated. 
     Container  6   b  may be made from plastic, steel or other material. 
     Preferably drive  1  will have a minimum protrusion to allow the containers to be stored in close proximity. 
     The assembly as described above is usually manufactured of plastic or a metal such as stainless steel. 
     Although the particular preferred embodiments of the invention have been disclosed in detail for illustrative purposes, it will be recognized that variations or modifications of the disclosed apparatus lie within the scope of the present invention.