Patent Application
20140313853
The present invention relates generally to mixer assemblies. In particular, the present invention is directed to a mixer assembly having two stages, with each stage having different operational characteristics.
Mixer assemblies for mixing liquids of various viscosities have been available for many years. Typically such mixers have a drive shaft extending from and operationally connected to a source of motive power, and an agitator or stirring component shaped to effect a particular mixing result. In the case of paints and chemicals stored in cans and large drums, mixers tend to have an elongated shaft to enable positioning the stirring component laterally within the confines of the container holding the substance to be mixed, and more importantly vertically so that the contents of the bottom of the container can be stirred. This vertical displacement capability is of increased importance with high viscosity materials as some settling of the material will typically occur. While some prior art devices are reasonably effective for their intended purpose, they tend to suffer from drawbacks. First, the agitator component tends to be either rigid or flexible, with the drawback being that a rigid agitator e.g. blades or paddles will tend to be affected by coming into contact with the sides of the container. This is especially true when the mixer is powered by a small drill or the like which has limited torque when applied to a long shaft. Flexible agitators tend to have limited effectiveness with heavy sediment which can collect at the bottom of, e.g., a can of paint. Also, especially in the case of an elongated shaft, a considerable amount of the product mixed will remain on the shaft and agitator after mixing, and this product will drip onto the surface supporting the can or drum which both wastes product and can have a deleterious effect on the surface.
U.S. Pat. No. 5,941,636 issued to one Lu is an example of a typical drill powered mixer assembly. The assembly has three vertically displaced agitators, each having two opposing, generally rigid blades. The blades, which are pivotally attached to the shaft with a retainer, extend horizontally upon rotation of the shaft. The drawback is that the rigid agitators are subject to heavy friction when in contact with the sides of the container, which slows the mixer and limits effectiveness. Also, while rigid, the small blades are not sturdy enough to break up deposits which may collect on the bottom of the container.
U.S. Pat. No. 7,329,040 issued to Elrod is a drill powered mixing assembly having a single agitator composed of a two link chain. The relative short chain connected close to the drive shaft provides very little angular momentum and again is not effective at removing and stirring deposits.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.
The present invention overcomes the disadvantages of the prior art by providing a mixer assembly having vertically displaced differential agitators. The first agitator is a primary mixing component formed of a hub having slots for positioning and securing radially extending angularly displaced stirring members. The hub is of a unitary construction and has three arcuate generally convex sidewalls attached about a central bore for receiving a drive shaft. The spaces between vertically extending edges of the sidewalls form the slots into which the stirring members are pivotally attached. The second agitator is a secondary mixing component formed of a disc shaped retaining member with stirring members angularly displaced about the edge of the disc. The stifling members of both the first and second agitators extend horizontally with rotation of the drive shaft, with the first agitator effective for both loosening sediment and stirring, while the second agitator increases the stirring effect. Both stifling members are hingedly attached to create a whipping effect which increases stirring velocity. A separate detached component is used to remove excess liquid from the drive shaft when the mixing action is completed.
Accordingly, it is a principal object of the invention to provide an improved mixer assembly.
It is another object of the invention to provide an improved mixing assembly having two differential, vertically displaced agitators.
It is another object of the invention to provide an improved mixing assembly having a first, more robust agitator for mixing at the bottom end of a container, and a second agitator for increasing stirring velocity.
Finally, it is a general object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.
Various other objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:
Referring now to
A key aspect of the invention 10 is its ability to be effectively employed to mix or stir liquids of various viscosities. To that end, a pair of agitators or mixing components are utilized, preferably in tandem for most mixing applications. The first mixing component 20 is formed of a robust hub portion 22, with a plurality of, in this case three, stifling elements 23 hingedly attached thereto, in angularly spaced relation as will be explained in more detail below. Referring now particularly to
The stirring elements 23 are formed from a chain made of metal or other durable material and preferably having at least two double loop links. While more or fewer links may be used, the two double loop link configuration is optimal for mixing. Also, the size of the double loop links are varied depending upon the size of the mixer, that is, a larger mixer will require larger links to produce a horizontal rotational plane of a larger diameter. In accordance with one aspect of the invention, it is preferable to use larger double loop links to increase the diameter of the rotational plane, as opposed to adding more links of a smaller size to increase the diameter of the rotational plane. A larger mixer is desirable when mixing the contents of a large, e.g., 55 gallon drum, container. It can be appreciated that a larger and deeper container will require a longer shaft 12 and a commensurately larger mixing component 20.
The connecting loop 40 of the first two loop link is hingedly attached to the hub 22 so that the elements 23 are freely hanging from the hub 22 when stationary so that the component 20 can be pushed through a bung hole in a container as will be discussed in more detail later. The loop 40 is attached to the hub 22 via bolt 36 within cooperating slot 32, and is permanently oriented vertically widthwise during rotation, that is, the opposing sides 42, 44 of the loop 40 are vertically disposed as the end portion 46 of the loop 40 is “pinched” within the slot 32 to limit rolling or wobbling of the loop 40. This permanent vertical orientation, combined with the radial spacing (from the shaft) of the element 23 due to the configuration of the hub 22, increases spin velocity by increasing the minimum radius of the element 23 relative to the shaft 12 during rotation as shown particularly in
Referring now particularly to
The component 50 is in two parts. The first part is a disc shaped flange or hub 52 which can be securely attached to the shaft 12 using any suitable attachment means such as welding, the attachment means serving to prevent rotation of the flange 52 relative to the shaft 12 as well as vertical displacement. The flange 52 can alternatively be adjustably and removably positioned on the shaft 12 using either a conventional set screw or roll pin assembly 53, 55, either of which is adapted to fit within slot 57 in the manner as described above. The flange 52 is formed of metal or other rigid, durable material. Three slots 54, angularly displaced by 120 degrees function as attachment points for each of the three stifling elements 58. The second part of the component 50 are the stirring elements 58, which are in the form of a chain having preferably two double loop links as per the above discussion. The effective radius of the elements 58 is increased by increasing the size of the double loop links. The connection loops 60 are looped within the slots 54 and are essentially hingedly attached to the flange 50 when the component is stationary (i.e., not rotating under motive power). When rotating however, connection loops 60 are locked onto the hub 52, more or less vertically disposed as described above, but in angular relation relative to the shaft 12 as can be seen in
As previously stated, the invention 10 has utility for mixing liquids of various viscosities. To that end the combination of mixing components 20, 50 positioned on the shaft 12 is selected in accordance with the viscosity. For a low viscosity fluid, a single component 50 is preferably used, the component 50 attached at the end of the shaft 12. If the low viscosity fluid is in a large container it would of course be advantageous to use two vertically spaced components 50 vertically spaced on the shaft 12. For medium viscosity fluids such as paints, where some sedimentation may occur, both components 20, 50 may be positioned on the shaft 12 as shown in
In use, the components 20 or 50 are positioned on the shaft 12 in the appropriate configuration in accordance with the liquid or product to be mixed as discussed above. Both components 20, 50 are sized for insertion into a bung hole or other mixing hole in a container for the product to be mixed. The drill 13 or other source of motive power is activated causing the stirring elements 23 and/or 58 of components 20 or 50 to extend in a horizontal plane to effect mixing of the product. The shaft 12 can be manipulated vertically and horizontally to effect mixing of the entire contents of the container in a manner well known in the art. When the mixing action is completed the shaft 12 is removed from the container, and preferably positioned in a container of water or solvent to remove product from the shaft 12 and mixing components 20, 50.
Removal of the shaft 12 from the container will ordinarily result in some of the liquid or product dripping onto the support surface upon which the container rests. To that end, a containment tube 70 is provided. The tube 70 expedites the removal process as most of the excess product can be effectively “squeegeed” from the shaft 12. The tube 70 is essentially cylindrical and includes a slot 72 allowing for insertion of the shaft 12. A partial gasket member 74 is inserted into one end of the tube 70 as by frictional fit, and is preferably at least somewhat compressible. Alternatively, the gasket 74 may be glued or otherwise attached to the tube 70. The partial gasket 74 has an angled guiding slot 76 formed therein, the slot terminating in an orifice 78 sized to snugly and slidably receive the shaft 12. In use, the shaft 12 is positioned within the tube 70 with the proximal end 80 of the shaft positioned within orifice 78. The tube 70 is then slid down the shaft 12 to squeegee product from the shaft 12, the outer surface of the tube serving to maintain the users hand a distance away from the product.
Referring now to
From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions.
It is to be understood that the present invention is not limited to the sole embodiment described above, but encompasses any and all embodiments within the scope of the following claims:
