Abstract:
A high-speed mixer includes an open frame structure having a bowl tiltably supported therein. A drive assembly is cantilevered from one end of the open frame structure and directly couples to an agitator rotatable supported in the bowl. The drive assembly is sufficiently self-enclosed to afford the use of an open frame construction without additional enclosures to prevent contamination and facilitate sanitation.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims the benefit of U.S. Provisional Application No. 60/601,717 filed on Aug. 13, 2004. The disclosure of the above application is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to a dough mixer, and more particularly to an open-frame, direct-drive high speed mixer for preparing dough and batters.  
       BACKGROUND OF THE INVENTION  
       [0003]     Dough mixers typically fall into one of three categories spiral mixers, vertical mixers, and, horizontal mixers. Large commercial and wholesale bakeries utilize horizontal batch mixers which provide a flexible, cost-effective and reliable means for mixing. Horizontal mixers have an elongated mixing chamber disposed generally horizontally with respect to the ground surface by a frame. An elongated, horizontal mixing shaft with mixing arms or blades extending therefrom rotates around the inside of the mixing chamber. The horizontal mixing shaft extends out of the chamber at both ends of the mixing chamber and is supported for relative rotation movement on bearings. A drive mechanism including a chain or belt couples the shaft to a motor for rotating the mixing shaft on the mixing chamber. The drive mechanism may drive one end of the mixing shaft or at both ends of the mixing shaft with a synchronous drive mechanism. An indirect drive mechanism as describe above has certain inherent power losses associated therewith.  
         [0004]     An indirect drive as described above also requires that the chain or belt in the drive mechanism be properly set up and maintained to ensure efficient operation. Specifically, the chain or belt must be tensioned for transmitting the necessary torque to rotate the mixing shaft. In may be necessary to provide a tensioner in the drive mechanism to maintain proper tension. Likewise, the various components in the drive mechanism must be periodically lubricated. As such, conventional belt or chain driven mixer can present set-up and maintenance tasks.  
         [0005]     Furthermore, in the food industry the complexity of the machinery directly affects the sanitation of the mixer. For this reason, the mixer, and in particular the various drive components are concealed in a covered enclosure to prevent contamination of the food products being mixed in the mixing chamber, as well as to prevent dough ingredients from dirtying the drive mechanism. While the enclosure functions sufficiently in this regard, it complicates the process for cleaning and sanitizing the mixer.  
       SUMMARY OF THE INVENTION  
       [0006]     In accordance with the present teachings, a high-speed mixer is provided which includes an open frame structure and a drive assembly directly coupled to an agitator rotatable supported in a bowl without the use of chains or belts. The drive assembly is sufficiently self-enclosed to afford the use of an open frame construction without additional enclosures to prevent contamination and facilitate sanitation.  
         [0007]     Further areas of applicability of these teaching will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]     The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:  
         [0009]      FIG. 1  is a front elevation of the high speed mixer shown in  FIG. 1 ;  
         [0010]      FIG. 2  is a top plan view of the high speed mixer shown in  FIG. 1 ;  
         [0011]      FIG. 3  is an end elevation of the high speed mixer shown in  FIG. 1  showing the mixing bowl in an upright position; and  
         [0012]      FIG. 4  is an end elevation of the high speed mixer showing the mixing bowl in a tipped or tilted position. 
     
    
     DETAILED DESCRIPTION  
       [0013]     The following detailed description is merely exemplary in nature and is in no way intended to limit the claimed invention, its application, or uses. With reference now to the drawings, a high-speed horizontal mixer  10  well-suited for use to make batter and yeast dough for baked goods such as bagels, bread, bums, muffins, pizza crust, rolls and tortilla shells is illustrated. The mixer  10  includes an open frame structure  12  which supports the bowl  14 . The bowl  14  is supported in frame structure  12  at bearing assemblies  16 . The bowl  14  is rotatably supported for movement through more than ninety degrees from an upright position, as shown in  FIGS. 1-3 , for loading and mixing and a dumped or tilted position, as shown in  FIG. 4 , for unloading the dough for subsequent processing. The bowl  14  may optionally be equipped with a stainless steel refrigeration jacket to provide a cooling function during the mixing operation.  
         [0014]     Referring now to  FIG. 1 , the frame structure  12  includes a pair of uprights  16 ,  18  transversely spaced apart by cross-members  20 ,  22 . In this manner, the uprights  16 ,  18  define an open central region above the cross-member  20  where the bowl  14  is supported. Upright  16  includes a pair of posts  24 ,  26  laterally spaced apart by supports  28 ,  30 ,  32 . Similarly, upright  18  includes a pair of posts  34 ,  36  laterally spaced apart by supports  38 ,  40 ,  42 . A support leg  44  extends downwardly and outwardly from cross-member  20  and outwardly from upright  16  for transversely stabilizing the frame structure  12 . As shown in  FIGS. 3 and 4 , support legs  46  (one shown) extend downwardly from cross-member  20  and outwardly from uprights,  16 ,  18  at the back of the open frame structure  12  for laterally stabilizing the frame structure  12 . The open frame structure  12  is such that the front of the mixer  10  is substantially free of transverse support structures, thereby enabling quick and easy sanitation and maintenance of both the machinery and the surrounding floor/support structure.  
         [0015]     As stated above, the bowl  14  is supported from the uprights  16 ,  18  by bearing assemblies  44 ,  46  which enable the bowl to be rotated between upright and tilted positions. Bearing assemblies  44 ,  46  are secured to the uprights  16 ,  18  supported above the supports  30 ,  40 .  
         [0016]     A direct drive assembly  48  including a reducer assembly  50  is cantilevered from the frame structure  12  outside of upright  16 . A motor  52  is vertically mounted to the upright  16  such that a motor shaft is extends into the bottom of the reducer assembly  50  and couples to the input side thereof. The output side of the reducer assembly  50  is directly coupled to the horizontal shaft  56  of an agitator  58 . In this manner the drive assembly  48  provides a single end direct drive mechanism without requiring additional drive chains or belts. Furthermore, the reducer mechanism provides power transmission from an input that is oriented 90° relative to the output, thereby providing a compact packaging of the direct drive assembly  48  at one of the mixer  10 . As presently preferred, motor  52  is a 2 speed TEFC motor with SMC high torque design, but could alternately be an inverter duty TEFC motor or single speed motor. The reducer assembly  50  and the motor  52  are self-enclosed and do not require additional housing to provide adequate sanitation.  
         [0017]     As best seen in  FIGS. 1 and 3 , the agitator  58  is a split hub agitator having a pair of hubs  60  located at each end of the agitator shaft  56 . A set of arms  62  extend radially from the shaft  56  to support a roller bar  64  at the end thereof. As present preferred, the agitator  58  includes three roller bars  64  which are positioned and rotate within the bowl  14  for mixing product therein. One or more breaker bars (not shown) may also be employed on the agitator  58  or in the bowl  14 .  
         [0018]     The agitator shaft  56  is rotatably supported by bearing assemblies  44 ,  46 . In this regard, each bearing assemblies  44 ,  46  provide a pair of concentric bearing mechanisms having a first bearing mechanism rotatably supporting the agitator shaft  56  and a second bearing mechanism rotatable supporting the bowl  14 .  
         [0019]     In an optionally preferred arrangement, a canopy or shroud  66  is supported on the top of the frame structure  12  and includes a flour gate assembly  68  above the bowl  14 . The canopy  66  covers the opening of the bowl  14  when in the upright position but does not otherwise enclose the frame structure  12 . The flour gate assembly  68  provides a closable aperture through which raw products used in the dough recipe can be loaded into the bowl  14 . Other ingredient inlets and features can be provided as necessary. As presently preferred the frame structure  12 , bowl  14 , agitator  58  and the canopy  66  are fabricated from stainless steel. The direct drive assembly  48  is fabricated from heavy duty materials to provide continuous, reliable service and production.  
         [0020]     The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.