Abstract:
A slicing blade for a slicing machine includes a center region connectable to a source of rotary power to be rotated about an axis, and a cutting edge region driven into rotation by the center region and having a discontinuous cutting edge. The discontinuous cutting edge is formed by a plurality of notches along the cutting edge region. The notches are formed by serrations arranged on at least one face of the cutting edge region. The notches can have a consistent pitch between adjacent notches. The notches can be arranged continuously around the cutting edge. The notches can alternately be arranged in sections, the sections spaced apart around the cutting edge region.

Description:
[0001]     This application claims the benefit of U.S. Provision Application Ser. No. 60/592,528 filed Jul. 30, 2004. 
     
    
     TECHNICAL FIELD OF THE INVENTION  
       [0002]     The present invention relates to slicing blades for a slicing machine, particularly for a high speed slicing machine.  
       BACKGROUND OF THE INVENTION  
       [0003]     Food loaves come in a variety of shapes (round, square, rectangular, oval, etc.), cross-sections, and lengths. Such loaves are made from various comestibles, such as meat, cheese, etc. Most loaves are provided to an intermediate processor who slices and packages the products in groups for retail.  
         [0004]     A variety of machines have been developed to slice such loaves. One such machine is an FX180™ available from Formax, Inc., of Mokena, Ill. The FX180™ machine is a high speed food loaf slicing machine that slices one, two, or more food loaves simultaneously using one cyclically driven slicing blade. Independent loaf feed drives are provided so that slices cut from one loaf may vary in thickness from slices cut from the other loaf. The machine includes a slicing station that is enclosed by a housing, except for a limited slicing opening. The slicing blade is disposed in the slicing station and a drive rotates the slicing blade at a predetermined cyclical rate on a cutting path through a slicing range that intersects the food loaves as they are fed into the slicing station.  
         [0005]     In the foregoing machine, the food loaf slices are received in groups of predetermined weight on a receiving conveyor that is disposed adjacent the slicing blade. The receiving conveyor receives the slices as they are cut by the slicing blade. In many instances, neatly aligned stacked groups are preferred and, as such, the sliced product is stacked on the receiving conveyor before being transferred from the machine. In other instances, the groups are shingled so that a purchaser can see a part of every slice through a transparent package. In these other instances, conveyor belts of the receiving conveyor are gradually moved during the slicing process to separate the slices.  
         [0006]     Slicing blades can have round slicing edges or involute shaped slicing edges such as disclosed in U.S. Pat. No. 6,484,615.  
         [0007]     The present inventors have recognized that when slicing whole muscle food products such as ham or poultry, if muscle fibers within the whole muscle food products happen to be out of alignment with a blade path of a rotating slicing blade, the blade may tend to push or pull the product into alignment with the meat fibers during slicing. Because the muscle fibers are randomly aligned within the food product, the pushing or pulling of the food product by the blade can result in inconsistent slice thicknesses.  
         [0008]     The present inventors have recognized that it would be desirable to provide a slicing machine that is capable of slicing food products with a consistent thickness, including whole muscle food products.  
       SUMMARY OF THE INVENTION  
       [0009]     The present invention provides an improved blade for a slicing machine that does not distort the product being cut along meat fibers within the product. The invention is particularly advantageous applied to a high speed slicing machine.  
         [0010]     The present invention provides a rotatable blade for a slicing machine that has a cutting edge region having a discontinuous cutting edge. The blade cutting edge region preferably has a plurality of notches arranged intermittently or continuously along its cutting edge. The notches are preferably formed by obliquely cut serrations present on at least one face of the cutting edge region.  
         [0011]     According to the preferred embodiment, the notches can have a consistent pitch between adjacent notches. The notches can be arranged continuously around the cutting edge. Alternately, the notches can be arranged in sections, the sections spaced apart around the cutting edge region.  
         [0012]     According to the preferred embodiment, the notches can have a pitch between about 0.18 to 0.5 inches. The serrations can have a maximum depth into the blade of between about 0.02 to 0.09 inches. The serrations can have a length of between about 0.09 to 0.5 inches. The notches can have a width of between about 0.09 to 0.38 inches. The notches can have a depth measured radially inward from an edge of the blade of between about 0.03 inches to about 0.12 inches.  
         [0013]     According to one exemplary embodiment, the notches have a pitch of about 0.38 inches. The serrations have a depth of 0.032. The serrations have a length of about 0.38 inches. The notches have a width of about 0.19 inches. The notches have a depth measured radially inward from an edge of the blade of about 0.06 inches.  
         [0014]     The blade of the invention is particularly effective when the cutting edge region is configured in an involute shape. The blade of the invention is particularly suited for use on a high speed slicing machine such as disclosed in U.S. Pat. No. 6,484,615 or as commercially available as a FX180™ or SNS® slicing machine and/or system available from Formax, Inc. of Mokena, Ill., USA.  
         [0015]     The slicing blade of the invention aggressively slices through products including whole muscle meat products without distorting the product by pulling the product to align the slicing blade along the muscle fiber. The slicing blade of the invention provides for a consistent thickness of whole muscle meat products.  
         [0016]     Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]      FIGS. 1 and 2  are perspective views of various aspects of one prior art type of slicing machine that may use the slicing blade of the present invention.  
         [0018]      FIG. 3  is a diagrammatic sectional view of a slicing station of the machine of  FIGS. 1 and 2 .  
         [0019]      FIG. 4  is a front view of an involute slicing blade of the invention.  
         [0020]      FIG. 5  is a perspective view of the blade of  FIG. 4 .  
         [0021]      FIG. 6  is an enlarged perspective view of a portion of the blade of  FIGS. 4 and 5 .  
         [0022]      FIG. 7  is a diagrammatic view of a grinding wheel preparing the blade of the invention.  
         [0023]      FIG. 8  is a sectional view of the grinding wheel taken along line  8 - 8  of  FIG. 7 . 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0024]     While this invention is susceptible of embodiment in many different forms, there are shown in the drawings, and will be described herein in detail, specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated.  
         [0025]      FIG. 1  illustrates one embodiment of a food loaf slicing machine  50  that may incorporate the slicing blade of the present invention. The slicing machine can be a high speed slicing machine such as disclosed in U.S. Pat. No. 6,484,615, herein incorporated by reference, or as commercially available as a FX180™ or SNS® slicing machine and/or system available from Formax, Inc. of Mokena, Ill., USA.  
         [0026]     Slicing machine  50  comprises a base  51  that is mounted upon four fixed pedestals or feet  52  (three of the feet  52  appear in  FIG. 1 ) and has a housing or enclosure  53  surmounted by a top  58 . Base  51  typically affords an enclosure for a computer  54 , a low voltage supply  55 , a high voltage supply  56 , and a scale mechanism  57 . Base enclosure  53  may also include a pneumatic supply or a hydraulic supply, or both (not shown).  
         [0027]     The slicing machine  50  may include a conveyor drive  61  utilized to drive an output conveyor/classifier system  64 .  
         [0028]     The slicing machine  50  of the illustrated embodiment further includes a computer display touch screen  69  in a cabinet  67  that is pivotally mounted on and supported by a support  68 . Support  68  is affixed to and projects outwardly from a member  74  that constitutes a front part of the housing of slicing station  66 .  
         [0029]     The upper right-hand portion of slicing machine  50 , as seen in  FIG. 1 , comprises a loaf feed mechanism  75  which, in machine  50 , includes a manual feed from the right-hand (far) side of the machine and an automated feed from the left-hand (near) side of the machine. Loaf feed mechanism  75  has an enclosure that includes a far-side manual loaf loading door  79  and a near-side automatic loaf loading door  78 .  
         [0030]     Referring first to conveyor/classifier system  64  at the left-hand (output) end of slicing machine  50  as illustrated in  FIG. 2 , it is seen that system  64  includes an inner stacking or receiving conveyor  130  located immediately below slicing station  66 . Conveyor  130  is sometimes called a “jump” conveyor. From conveyor  130  groups of food loaf slices, stacked or shingled, are transferred to a decelerating conveyor  131  and then to a weighing or scale conveyor  132 . From the scale conveyor  132  groups of food loaf slices move on to an outer classifier conveyor  134 . On the far side of slicing machine  50  the sequence is substantially the same.  
         [0031]     Slicing machine  50  may further include a vertically movable stacking grid  136  comprising a plurality of stack members joined together and interleaved one-for-one with the moving elements of the inner stack/receive conveyor  130 . Stacking grid  136  can be lowered and raised by a stack lift mechanism  138 . Alternatively, food loaf slices may be grouped in shingled or in stacked relationship directly on the receive/stack conveyor  130 , with a series of stacking pins replacing grid  136 . When this alternative is employed, lift mechanism  138  is preferably connected directly to and is used for vertical positioning of conveyor  130 .  
         [0032]     Loaf feeding mechanism  75  preferably includes a back-clamp respectively associated with each food loaf. The back-clamps  205  secure the rear portion of each loaf and assist in advancing each loaf at individually determined rates into the slicing station  66 . The loaf feeding mechanism  75  also preferably comprises a system of short conveyors for advancing food loaves from loaf feed mechanism  75  into slicing station.  FIG. 2  shows two short lower loaf feed conveyors  163  and  164  on the near and far-sides of slicing machine  50 , respectively. These short lower conveyors  163  and  164  are located immediately below two short upper feed conveyors  165  and  166 , respectively. An end plate is disposed adjacent the conveyors  163 - 166  with recesses for guiding the respective loaves to the blade.  
         [0033]     The slicing machine  50  of  FIG. 1  is shown in a state ready for operation. There is a food loaf  91  on tray  85 ; waiting to be loaded into loaf feed mechanism  75  on the near-side of machine  50 . Machine  50  produces a series of stacks  92  of food loaf slices that are fed outwardly of the machine, in the direction of the arrow A, by conveyor classifier system  64 . Machine  50  also produces a series of stacks  93  of food loaf slices that move outwardly of the machine on its output conveyor system  64  in the direction of arrow A.  
         [0034]     The loaf feed mechanism  75  drives the loaves into the slicing station where they are sliced by a rotating knife blade (not illustrated in  FIG. 2 ) that is disposed at the output portions of the short conveyors. The thickness and total weight of the slices are controlled by computer  54  which actuates various mechanical components associated with the slicing operation. The slice thickness and total weight for each sliced group are programmed through the touch screen  67  which interfaces with computer  54 . As the blade slices the loaves, the slices are deposited on receiving conveyor  130  where the proper numbers of slices are either stacked or shingled. The receiving conveyor  130  then drives the groups from the slicing station for subsequent classifying and packaging.  
         [0035]     Some of the drive motors for operating the mechanisms in slicing machine  50  are shown in  FIG. 2 . The drive motor for the blade in slicing station  66  is preferably a D.C. variable speed servo motor  171  mounted in the machine base  51 . The receiver lift mechanism  138  is driven by a stacker lift motor  173 , again preferably a variable speed D.C. servo motor. On the near side of machine  50  the loaf feed drive mechanism comprising the back-clamp  205  and the short loaf feed conveyors  163  and  165  is driven by a servo motor  174 . A like motor on the far side of machine  50  (not shown) affords an independent drive for the back-clamp and the “short” loaf feed conveyors  164  and  166  on that side of the slicing machine.  
         [0036]     A knife blade  210  for use in the slicing machine of  FIGS. 1 and 2  is shown in  FIGS. 3-6 . The blade  210  is disposed interior to a protective housing or shield to prevent injury to machine operators. As shown in  FIG. 3 , the blade is arranged to slice a food loaf  211  to produce slices  212  which are deposited on the conveyor  130 .  
         [0037]     As shown in  FIGS. 4-6 , the blade  210  has a tapered edge region  215  having a cutting edge region  217 . The blade  210  illustrated is involute shaped, although a circular blade or other shaped blade is also encompassed by the invention. The blade  210  is rotated about its rotation axis  220  by, for example, the servomotor drive  171  or the like. Rotation of the blade  210  is coordinated with the movement of the food loaves by the loaf feeding mechanism  75  and with the operation of the receiving conveyor  130  that receives the sliced food loaves for stacking or shingling.  
         [0038]     The blade  210  includes obliquely cut serrations  230  on at least one face  217   a  ( FIGS. 3 and 5 ) of its cutting edge region  217 . The serrations  230  on the face  217   a  form substantially U-shaped notches  232  open along a cutting edge  217   c.  The notches  232  can be arranged continuously along the cutting edge  217   c  as shown in  FIG. 4  or intermittently as shown in  FIG. 5 . In  FIG. 5 , the notches  232  are grouped in sections  240  that are separated by plain sections  242  of the cutting edge  217   c.    
         [0039]     As shown in  FIG. 6 , the notches can have a pitch P between about 0.18 to 0.5 inches. The serrations can have a maximum depth D into the blade of between about 0.02 to 0.09 inches. This depth D is measured along a radial direction R of the grinding wheel as shown in  FIG. 7 . The serrations can have a length L of between about 0.09 to 0.5 inches. The notches can have a width W of between about 0.09 to 0.38 inches. The notches  232  can have a depth F measured radially along the blade of between about 0.03 inches to about 0.12 inches.  
         [0040]     According to one exemplary embodiment, the notches have a pitch P of about 0.38 inches, a depth D of about 0.032 inches, a length L of about 0.38 inches, and a width W of about 0.19 inches. The notches  232  can have a depth F measured radially along the blade of about 0.06 inches.  
         [0041]      FIGS. 7 and 8  illustrate a grinding wheel  300  used to form the serrations  230 . The grinding wheel has a radius range  302  preferably within a range of about 0.06 inches to 0.62 inches. According to a preferred embodiment the radius range is about 0.38 inches. The grinding wheel has a thickness  304  preferably within the range of about 0.12 inches to 0.5 inches. According to a preferred embodiment the thickness is about 0.31 inches. The depth  306  of the serration  230  is preferably within a range of about 0.02 inches to 0.09 inches. According to a preferred embodiment, the depth of the serrations  230  is about 0.032 inches.  
         [0042]     Numerous modifications may be made to the foregoing system without departing from the basic teachings thereof. Although the present invention has been described in substantial detail with reference to one or more specific embodiments, those of skill in the art will recognize that changes may be made thereto without departing from the scope and spirit of the invention as set forth in the appended claims.