Abstract:
An agitator assembly for use with industrial mixers that includes at least two rotating agitators, wherein each rotating agitator includes an agitator shaft, wherein the agitator shaft defines an axis of rotation extending from a first end of the agitator shaft to a second end of the agitator shaft; and first, second, and third sweep blades mounted on the agitator shaft, wherein the pitch angle of each sweep blade relative to the axis of rotation of the agitator shaft is between 30-60°; and wherein the rotating agitators rotate in opposite directions relative to one another when the assembly is in use.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This patent application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/216,740 filed on Sep. 10, 2015, and entitled “Agitator and Agitator Assembly for Use with Industrial Mixers”, the disclosure of which is hereby incorporated by reference herein in its entirety and made part of the present U.S. utility patent application for all purposes. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The described invention relates in general to an agitator, and more specifically to an agitator and dual agitator assembly for use in large industrial and commercial mixers used for mixing viscous materials such as cookie dough. The agitator and dual agitator assembly of the present invention provide rapid and uniform mixing of dough or other materials within the mixing bowl of an industrial or commercial mixer. 
         [0003]    Certain known agitator assemblies for use in large-scale mixers include a pair of agitator shafts having a set of sweep blades mounted thereon. The rotation of the agitator shafts in these prior art systems often creates certain mixing discontinuities because the flow of material in the vicinity of the agitator assembly tends to be focused at the center of the agitator assembly. Accordingly, material at the periphery of a mixing bowl in which such an agitator assembly is positioned is often under-mixed and material at the center of such a mixing bowl is over-mixed. This non-uniform flow of material is not conducive to an efficient and rapid mixing operation. Thus, there is an ongoing need for an agitator and an agitator assembly that ensures that materials are mixed uniformly throughout the mixing bowl and there is also a need for an agitator design that improves mixing rates within a mixing bowl. 
       SUMMARY OF THE INVENTION 
       [0004]    The following provides a summary of certain exemplary embodiments of the present invention. This summary is not an extensive overview and is not intended to identify key or critical aspects or elements of the present invention or to delineate its scope. 
         [0005]    In accordance with one aspect of the present invention, a first agitator assembly for use with industrial mixers is provided. This agitator assembly includes at least two rotating agitators, wherein each rotating agitator includes an agitator shaft, wherein the agitator shaft defines an axis of rotation extending from a first end of the agitator shaft to a second end of the agitator shaft; and first, second, and third sweep blades mounted on the agitator shaft, wherein the pitch angle of each sweep blade relative to the axis of rotation of the agitator shaft is between 30-60°; and wherein the rotating agitators rotate in opposite directions relative to one another. 
         [0006]    In accordance with another aspect of the present invention, a second agitator assembly for use with industrial mixers is provided. This agitator assembly includes at least two rotating agitators, wherein each rotating agitator includes an agitator shaft, wherein the agitator shaft defines an axis of rotation extending from a first end of the agitator shaft to a second end of the agitator shaft; first, second, third, and fourth hubs mounted on the agitator shaft at predetermined locations, wherein the distances between the first and second hub, the second and third hub, and third and fourth hub are substantially equal; a first sweep blade mounted between the first hub and second hub; a second sweep blade mounted between the second hub and third hub; and a third sweep blade mounted between the third and fourth hub; wherein the pitch angle of each sweep blade relative to the axis of rotation of the agitator shaft is between 30-60°, wherein the rotating agitators rotate in opposite directions relative to one another when in use, and wherein the agitator assembly is adapted for use in a mixing bowl. 
         [0007]    In yet another aspect of this invention, a third agitator assembly for use with industrial mixers is provided. This agitator assembly includes at least two rotating agitators, wherein each rotating agitator includes an agitator shaft, wherein the agitator shaft defines an axis of rotation extending from a first end of the agitator shaft to a second end of the agitator shaft; first, second, third, and fourth hubs mounted on the agitator shaft at predetermined locations, wherein the distances between the first and second hub, the second and third hub, and third and fourth hub are substantially equal; a first sweep blade mounted between the first hub and second hub, wherein the first sweep blade is oriented with a forward sweep directionality; a second sweep blade mounted between the second hub and third hub, wherein the second sweep blade is oriented a forward sweep directionality; and a third sweep blade mounted between the third and fourth hub, wherein the third sweep blade includes a first section that is oriented with a forward sweep directionality and a second section that is oriented with a reverse sweep directionality; wherein the pitch angle of each sweep blade relative to the axis of rotation of the agitator shaft is fixed between about 30-60° and preferably at 45°, wherein the rotating agitators rotate in opposite directions relative to one another when in use, wherein the agitator assembly is adapted for use in a mixing bowl, and wherein the mixing bowl is a component of a large-scale industrial mixer. 
         [0008]    Additional features and aspects of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the exemplary embodiments. As will be appreciated by the skilled artisan, further embodiments of the invention are possible without departing from the scope and spirit of the invention. Accordingly, the drawings and associated descriptions are to be regarded as illustrative and not restrictive in nature. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The accompanying drawings, which are incorporated into and form a part of the specification, schematically illustrate one or more exemplary embodiments of the invention and, together with the general description given above and detailed description given below, serve to explain the principles of the invention, and wherein: 
           [0010]      FIG. 1  is a top view of a dual or double arm agitator assembly in accordance with an exemplary embodiment of the present invention showing the position of the dual agitators relative to one another; 
           [0011]      FIG. 2  is a side view of the agitator assembly of  FIG. 1 ; 
           [0012]      FIG. 3  is a perspective view of the agitator assembly of  FIG. 1 ; 
           [0013]      FIG. 4  is an end view of the agitator assembly of  FIG. 1 ; 
           [0014]      FIG. 5  is a perspective view of one of the individual agitator arms of the dual agitator assembly of  FIG. 1 ; 
           [0015]      FIG. 6  is side view of one of the individual agitator arms of the dual agitator assembly of  FIG. 1 ; 
           [0016]      FIG. 7  is a perspective view of the dual agitator assembly of  FIG. 1  properly positioned within the mixing bowl of an industrial mixer; and 
           [0017]      FIG. 8  is an end view of the agitator assembly of  FIG. 7 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]    Exemplary embodiments of the present invention are now described with reference to the Figures. Reference numerals are used throughout the detailed description to refer to the various elements and structures. Although the following detailed description contains many specifics for the purposes of illustration, a person of ordinary skill in the art will appreciate that many variations and alterations to the following details are within the scope of the invention. Accordingly, the following embodiments of the invention are set forth without any loss of generality to, and without imposing limitations upon, the claimed invention. 
         [0019]    The present invention relates in general to an agitator, and more specifically to an agitator and dual agitator assembly for use in large industrial or commercial mixers used for mixing large volumes (e.g., 100-5000 pounds) of viscous materials such as cookie dough. The agitator and dual agitator assembly of the present invention provide rapid and uniform mixing of dough within a mixing bowl. The dual agitator assembly of this invention includes an advanced swept-blade design that creates a substantially circuitous flow pattern within the mixing bowl and that provides significant improvement over prior art designs with regard to uniformity of mixing. Each of the agitators in the dual agitator assembly of the present invention typically includes three individual mixing blades in each separate blade component that is mounted on each agitator arm rather than two mixing blades, which is common in prior art systems. In the embodiments shown in the Figures, the pitch of the mixing blades is typically fixed at 45° relative to the rotating axis of the agitator arm on which the blades are mounted, although other angles are possible. 
         [0020]    With reference to  FIGS. 1-8 , an exemplary embodiment of dual agitator system or dual agitator assembly  10  includes first agitator  100  and second agitator  200 , which are rotatably mounted within mixing bowl  20 . The general construction of first and second agitators  100  and  200  is the same; however, when mounted in mixing bowl  10 , second agitator  200  is mounted in an opposite orientation relative to first agitator  100 . In other words, second agitator  200  is flipped 180° relative to first agitator  100 . This arrangement results in first agitator  100  moving the material being mixed in a direction opposite the direction in which second agitator  200  is moving the material, thereby resulting in extremely thorough mixing of the material. As shown in  FIG. 8 , when mounted in mixing bowl  10 , first agitator  100  is mounted slightly above second agitator  200 , which results in the material being mixed moving upward and downward in addition to moving left to right and right to left. Accordingly, the material being mixed is thoroughly circulated through mixing bowl  10 . 
         [0021]    First agitator  100  includes first hub  110 , second hub  130 , third hub  150 , and fourth hub  170 , all mounted on agitator shaft  102 . Three agitator blade components are mounted between the four hubs. The first agitator blade component includes first leg  112 ; first agitator blade  114 , which is mounted in a forward sweep directionality; second leg  116 ; first support  118  (mounted on first leg  112 ), which includes cap  120 ; and second support  122  (mounted on second leg  122 ), which includes cap  124 . The second agitator blade component includes third leg  132 ; second agitator blade  134 , which is mounted in a forward sweep directionality; fourth leg  136 ; third support  138  (mounted on third leg  132 ), which includes cap  140 ; and fourth support  142  (mounted on fourth leg  136 ), which includes cap  144 . The third agitator blade component includes fifth leg  152 ; first section of third agitator blade  154 , which is mounted in a forward sweep directionality; second section of third agitator blade  155 , which is mounted in a reverse directionality; sixth leg  156 ; fifth support  158  (mounted on fifth leg  152 ), which includes cap  160 ; and sixth support  162  (mounted on sixth leg  156 ), which includes cap  164 . 
         [0022]    Second agitator  200  includes first hub  210 , second hub  230 , third hub  250 , and fourth hub  270 , all mounted on agitator shaft  202 . Three agitator blade components are mounted between the four hubs. The first agitator blade component includes first leg  212 ; first agitator blade  214 , which is mounted in a forward sweep directionality; second leg  216 ; first support  218  (mounted on first leg  212 ), which includes cap  220 ; and second support  222  (mounted on second leg  222 ), which includes cap  224 . The second agitator blade component includes third leg  232 ; second agitator blade  234 , which is mounted in a forward sweep directionality; fourth leg  236 ; third support  238  (mounted on third leg  232 ), which includes cap  240 ; and fourth support  242  (mounted on fourth leg  236 ), which includes cap  244 . The third agitator blade component includes fifth leg  252 ; first section of third agitator blade  254 , which is mounted in a forward sweep directionality; second section of third agitator blade  255 , which is mounted in a reverse directionality; sixth leg  256 ; fifth support  258  (mounted on fifth leg  252 ), which includes cap  260 ; and sixth support  262  (mounted on sixth leg  256 ), which includes cap  264 . 
         [0023]    In exemplary embodiments of the present invention, the mixing blade pitch angle is substantially the same for all mixing blades mounted on the same agitator, as well as for all agitators being used in the mixing bowl, regardless of mixer size. As previously indicated, the pitch of the mixing blades may be fixed at 45° relative to the rotating axis of the agitator arm on which the blades are mounted; however, alternate embodiments include blade pitch angles of 30-60° relative to the rotating axis of the agitator arm on which the blades are mounted. A constant blade pitch angle used with various mixer sizes results in consistent mixing action within such mixers. The steeper pitch angle of the present invention (relative to prior designs that include pitch angles of 31 and 40°) incorporates individual ingredients within dough mixtures in shorter periods of time resulting in an overall decrease in required mixing time. Steeper pitch angles and shorter mixing times also incorporate fragile particulates in dough mixers more rapidly resulting in less damage to such particulates and an overall higher quality final product. Faster mix times also result in energy savings per batch of dough or other material. 
         [0024]    The mixing blades of this invention, which are typically stainless steel (as are the other components), include a smooth sweep transition from vertical blade to vertical blade. The total length of each mixing blade varies for different mixer sizes (i.e., capacities). By way of example, the length range for each mixing blade may be about 20 inches by about 74 inches. The diameter of each mixing blade also varies for different mixer sizes. By way of example, the diameter range may be about 7 inches to about 36 inches. To physically obtain a smooth sweep transition while maintaining a constant blade pitch angle for the different agitator length and diameter combinations, the number of sweep blades and the vertical blade offset angle may be varied. Tables 1 and 2, below: (i) provide information regarding agitator design standards and list actual values for use with standard mixer product lines and; (ii) provide instructions for determining various relevant design aspects. 
         [0000]    
       
         
               
             
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 Agitator Design Standards 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 DESIGN GROUP 
                 EAGLE 
                 EAGLE 
                 DG100/150 
                 DG200/250 
               
             
          
           
               
                 MODEL 
                 EDA25 
                 EDA70 
                 EDA100 
                 DA100 
                 DA150 
                 DA100HD3 
                 DA150HD2 
                 DA200 
                 DA250 
               
               
                 STD AGITATOR TYPE 
                 2 SWEEP 
                 2 SWEEP 
                 2 SWEEP 
                 2 SWEEP 
                 2 SWEEP 
                 2 SWEEP 
                 2 SWEEP 
                 2 SWEEP 
                 2 SWEEP 
               
               
                   
               
               
                 BOTTOM RADIUS 
                 6.500 
                 9.000 
                 11.000 
                 11.000 
                 11.000 
                 12.000 
                 12.000 
                 13.000 
                 13.000 
               
               
                 BOWL INSIDE LENGTH 
                 20.000 
                 27.000 
                 32.000 
                 32.000 
                 38.000 
                 30.000 
                 36.000 
                 40.000 
                 48.000 
               
               
                 NUMBER OF SWEEPS 
                   
                 2 
                 2 
                 2 
                 2 
                 2 
                 2 
                 2 
                 2 
               
               
                 HUB TO BOWL END 
                   
                 1.000 
                 1.000 
                 1,000 
                 1.000 
                 1.000 
                 1.000 
                 1.000 
                 1.000 
               
               
                 HUB CENTERS 
                   
                 11.000 
                 13.500 
                 12.750 
                 15.750 
                 11.500 
                 14.500 
                 16.500 
                 20.500 
               
               
                 BETWEEN HUBS 
                   
                 8.000 
                 10.500 
                 8.250 
                 11.250 
                 6.500 
                 9.500 
                 11.500 
                 15.500 
               
               
                 BLADE PITCH ANGLE-ALL 
                   
                 45.0 
                 45.0 
                 45.0 
                 45.0 
                 45.0 
                 45.0 
                 45.0 
                 45.0 
               
               
                 BLADE OFFSET ANGLE  
                   
                 84 
                 82 
                 81 
                 94 
                 68 
                 84 
                 88 
                 100 
               
               
                 BASED ON MODEL 
                   
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 (SEE INSTRUCTIONS BELOW) 
               
               
                   
               
             
          
           
               
                   
                 DESIGN GROUP 
                 DG300/350 
                 DG400/500 
                 DG600 
                 DG700 
                 DG800 
               
             
          
           
               
                   
                 MODEL 
                 DA300 
                 DA350 
                 DA400 
                 DA500 
                 DA600 
                 DA700 
                 DA800 
               
               
                   
                 STD AGITATOR TYPE 
                 3 SWEEP 
                 3 SWEEP 
                 3 SWEEP 
                 3 SWEEP 
                 3 SWEEP 
                 3 SWEEP 
                 3 SWEEP 
               
               
                   
               
               
                   
                 BOTTOM RADIUS 
                 13.000 
                 13.000 
                 14.000 
                 14.000 
                 16.000 
                 17.000 
                 18.000 
               
               
                   
                 BOWL INSIDE LENGTH 
                 52.000 
                 58.000 
                 58.000 
                 69.000 
                 69.000 
                 69.000 
                 74.000 
               
               
                   
                 NUMBER OF SWEEPS 
                 3 
                 3 
                 3 
                 3 
                 3 
                 3 
                 3 
               
               
                   
                 HUB TO BOWL END 
                 1.000 
                 1.000 
                 1.000 
                 1.000 
                 1.000 
                 1.000 
                 1.000 
               
               
                   
                 HUB CENTERS 
                 15.000 
                 17.000 
                 17.000 
                 20.667 
                 20.333 
                 20.333 
                 21.667 
               
               
                   
                 BETWEEN HUBS 
                 10.000 
                 12.000 
                 12.000 
                 15.667 
                 14.333 
                 14.333 
                 14.667 
               
               
                   
                 BLADE PITCH ANGLE-ALL 
                 45.0 
                 45.0 
                 45.0 
                 45.0 
                 45.0 
                 45.0 
                 45.0 
               
               
                   
                 BLADE OFFSET ANGLE  
                 77 
                 88 
                 82 
                 94 
                 86 
                 82 
                 85 
               
               
                   
                 BASED ON MODEL 
                   
                   
                   
                   
                   
                   
                   
               
               
                   
                 (SEE INSTRUCTIONS BELOW) 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
               
               
             
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 Determination of Agitator Design Standards 
               
             
          
           
               
                   
                   
                   
                   
                 ANGLE 
                   
                   
                   
                 ANGLE 
               
               
                   
                   
                   
                   
                 FROM 
                   
                   
                   
                 FROM 
               
               
                 POINT 
                 X 
                 Y 
                 Z 
                 VERTICAL 
                 X 
                 Y 
                 Z 
                 VERTICAL 
               
               
                   
               
               
                 SWEEP PROFILE (Sketch 5) 
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 CORNER 1-LOWER FRONT 
                 1.250 
                 9.969 
                 5.811 
                   
                   
                   
                   
                   
               
               
                 CORNER 2-LOWER REAR 
                 2.311 
                 9.969 
                 4.750 
                   
                   
                   
                   
                   
               
               
                 CORNER 3-UPPPER FRONT 
                 1.250 
                 17.469 
                 5.811 
                   
                   
                   
                   
                   
               
               
                 CORNER 4-UPPER REAR 
                 2.311 
                 17.469 
                 4.750 
                   
                   
                   
                   
                   
               
             
          
           
               
                 SWEET GUIDE PATH-FIXED (3DSKETCH 1)  
                 OUTSIDE 
                 INSIDE 
               
             
          
           
               
                 OUTSIDE RIGHT BLADE 
                 1.780 
                 17.469 
                 5.280 
                   
                 1.780 
                 9.969 
                 5.280 
                   
               
               
                 RIGHT BLADE CENTER 
                 −3.500 
                 18.250 
                 0.000 
                   
                 −3.500 
                 10.750 
                 0.000 
                   
               
               
                 INSIDE RIGHT BLADE 
                 −7.000 
                 17.911 
                 −3.500 
                   
                 −7.000 
                 10.411 
                 −3.500 
                   
               
               
                 INSIDE LEFT BLADE 
                 −21.667 
                 5.048 
                 −17.538 
                   
                 −21.667 
                 4.394 
                 −10.067 
                   
               
               
                 CENTER LEFT BLADE 
                 −25.167 
                 1.591 
                 −18.181 
                   
                 −25.167 
                 0.937 
                 −10.709 
                   
               
               
                 OUTSIDE LEFT BLADE 
                 −30.697 
                 −3.993 
                 −17.808 
                   
                 −30.697 
                 −4.647 
                 −10.336 
                   
               
               
                 OUTSIDE SWEEP GUIDE PATH- 
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 CALCULATED 
                   
                   
                   
                   
                   
                   
                   
                   
               
               
                 CALCULATED POINTS 
                 6 
                   
                   
                   
                 6 
                   
                   
                   
               
               
                 INSIDE RIGHT BLADE POINT ANGLE 
                 −11.057 
                   
                   
                   
                 −18.582 
                   
                   
                   
               
               
                 TOTAL ANGLE 
                 62.89 
                   
                   
                   
                 47.84 
                   
                   
                   
               
               
                 ANGLE PER POINT 
                 8.98 
                   
                   
                   
                 6.83 
                   
                   
                   
               
               
                 TOTAL DISTANCE 
                 −14.667 
                   
                   
                   
                 −14.667 
                   
                   
                   
               
               
                 DISTANCE PER POINT 
                 -2.095 
                   
                   
                   
                 −2.095 
                   
                   
                   
               
               
                 SWEEP RADIUS 
                 18.250 
                   
                   
                   
                 10.984 
                   
                   
                   
               
               
                 POINT 1 
                 −9.095 
                 17.145 
                 −6.254 
                 −20.04 
                 −9.095 
                 9.921 
                 −4.714 
                 −25.42 
               
               
                 POINT 2 
                 −11.191 
                 15.958 
                 −8.855 
                 −29.02 
                 −11.191 
                 9.289 
                 −5.861 
                 −32.25 
               
               
                 POINT 3 
                 −13.286 
                 14.380 
                 −11.238 
                 −38.01 
                 −13.286 
                 8.526 
                 −6.925 
                 −39.08 
               
               
                 POINT 4 
                 −15.381 
                 12.448 
                 −13.345 
                 −46.99 
                 −15.381 
                 7.641 
                 −7.890 
                 −45.92 
               
               
                 POINT 5 
                 −17.476 
                 10.212 
                 −15.126 
                 −55.98 
                 −17.476 
                 6.648 
                 −8.743 
                 −52.75 
               
               
                 POINT 6 
                 −19.572 
                 7.725 
                 −16.535 
                 −64.96 
                 −19.572 
                 5.560 
                 −9.472 
                 −59.59 
               
               
                   
               
             
          
         
       
     
         [0025]    While the present invention has been illustrated by the description of exemplary embodiments thereof, and while the embodiments have been described in certain detail, there is no intention to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the invention in its broader aspects is not limited to any of the specific details, representative devices and methods, and/or illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the general inventive concept.