Abstract:
A knife for a cutting wheel provided to slice food products including a knife holder having a recessed portion located along a leading side thereof, a clamp secured to the knife holder, and a cutting blade mounted between the clamp and knife holder along the leading side of the knife holder. A replaceable insert member with a wear surface is positioned within the recess of the knife holder, and this insert member is contiguous with the cutting blade and protrudes from the knife holder to provide a substitute leading edge therefore in close apposition to the cutting blade.

Description:
[0001]     This application claims the benefit of U.S. Provisional Application No. 60/535,819 filed Jan. 13, 2004. 
     
    
     BACKGROUND  
       [0002]     The present invention relates to a knife for a cutting wheel for a food product slicing apparatus, and more specifically, to an improved knife having a replaceable insert member provided along a leading side of the knife and adjacent to a cutting blade of such knife.  
         [0003]     Many types of food slicing apparatuses are known in which food products are transported into a rotating wheel having a plurality knives each with a cutting blade to cut the food products into slices. In the food processing industry, it is important that the food product be cut into slices having a uniform thickness without damaging the food product. Such thickness uniformity facilitates the further processing of the food product providing a maximum amount of usable food product with minimum amount of waste.  
         [0004]     An embodiment of a known rotatable cutting wheel described in U.S. Pat. Nos. 5,992,284 and 6,148,709, of which are incorporated herein by reference, is illustrated in  FIG. 1 . This known cutting wheel comprises a hub  10 , about which is concentrically arranged a rim  12  being interconnected by a plurality of knives  14 . Each of the knives  14  has a knife holder  18  securing a cutting blade  16  with a cutting edge  20  facing in the direction of rotation of the wheel indicated by arrow  28 . The cutting edge  20  of each knife  14  is located adjacent to a second edge  22  of an adjacent knife  14 . The second edge  22  extends substantially parallel to the cutting edge  20  of the adjacent knife  14  such that a radial space or gate opening  26  is formed extending between the hub  10  and the rim  12  which has a constant circumferential dimension throughout its radial length.  
         [0005]     As shown in  FIG. 1 , each knife  14  defines a back surface having a gauging portion  24 . In operation, food products are fed into the plane of the cutting wheel so as to maintain contact with the gauging portion of the knives as they pass through the food product. The dimension of the gate opening will accurately control the thickness of the sliced food product.  
         [0006]     An embodiment of the knives of the cutting wheel of U.S. Pat. Nos. 5,992,284 and 6,148,709 is shown in  FIGS. 2 and 3 . As can be seen, the knife  14  comprises the knife holder  18  on which the cutting blade  16  is mounted. The cutting blade may be permanently attached to the knife holder, or may be removably held by a clamping device. In this embodiment, the cutting blade  16  is held against a bevel surface  34  of the knife holder  18  by clamp  32  which is attached to the knife holder  18  by a plurality of fasteners  36 . The clamp  32  engages the fasteners  36  by way of keyhole-shaped slots  38  which enable removal of the clamp  32  such that the heads of the fasteners  36  are aligned with the larger opening portion of the keyhole shaped slots  38 . Locating studs  40  extend from the knife holder  18  and engage openings  30   a  and  30   b  in the cutting blade  16  to locate the cutting blade  16  on the knife holder  18 .  
         [0007]     The known knife holder  18  has a rear edge  22  formed thereon which extends obliquely with respect to the cutting edge  20  of the cutting blade  16 . The knife holder  18  has a hub mounting hole  46  and rim mounting holes  48   a  and  48   b  formed therein for attachment to the hub and rim, respectively of a cutting wheel. Moreover, the width of the knife holder  18  at the hub mounting end is less than the width of the knife holder  18  at the rim mounting end.  
         [0008]     Typically, the food product is transported through the cutting plane of the cutting wheel at a constant speed and the cutting wheel is rotated at a constant speed to produce slices having a generally uniform thickness.  
         [0009]     It has been found with the aforementioned knives of the known cutting wheel that the leading edge of knife holder undergoes considerable wear or is subjected to chipping or bending when harmful debris damages the knife when slicing food products. As a result, the knife holder often requires replacement which results in downtime of the cutting wheel and thus, the food processing operation is undesirably halted. Replacement of knife holders is expensive due to their specifically dimensioned configuration, and considerable time is required to disassemble the knife from the cutting wheel and the components thereof, and subsequently reassemble the new knife holder with the components onto the cutting wheel. Moreover, adjustment of the knife holders on the cutting wheel is cumbersome and requires precision that may not be feasible when assembled on a cutting wheel with multiple knives.  
         [0010]     Accordingly, there is a demand and a need for an improved knife holder wherein repair of such knife holders is greatly simplified and adjustment thereof is substantially facilitated.  
       SUMMARY  
       [0011]     In accordance with one aspect of the invention, there is provided an improved knife for a cutting wheel having a replaceable insert member for substitution as a leading edge of a knife holder adapted for mounting on a cutting wheel and securing a cutting blade. More specifically, in an embodiment of the invention, the knife holder of the improved knife defines mutually parallel first and second leading edges extending along a leading side thereof and a trailing edge located opposite the leading edges, a first surface between the first leading edge and the trailing edge, a second surface opposite the front surface and extending between the second leading edge and trailing edge, and a recess located along the leading surface and extending into at least a portion of the knife holder. A clamp is provided and attached to the front surface of the knife holder and is generally positioned along the leading surface of the knife holder. The cutting blade has a sharpened leading edge retained between the knife holder and the clamp so that the leading edge of the cutting blade is disposed on the front surface in front of the leading edges of the knife holder. The insert member is mounted in the recess of the knife holder and has a leading edge protruding from the upper and second leading edges of the knife holder and is generally contiguous therewith.  
         [0012]     By virtue of this design, the knife addresses the problem of replacement or adjustment of the knife holder due to wear by providing the replaceable insert member. Replacement of the insert member is easily conducted when mandated by wear occurring on an installed insert member, or should a differently shaped wear surface be required to accommodate a different shaped cutting blade. The insert member, while detachable and replaceable, is incorporated in the support structure for the knife in such a manner that the insert member is positively mechanically held from displacement during use of the knife.  
         [0013]     In accordance with another aspect of the invention, the knife may be adjusted relative to the cutting wheel by a plurality of tensioning fasteners. Such tensioning fasteners are configured for smooth rotation for adjustment of the knife holder. The tensioning fasteners are constructed to include fine threads at fine angles to achieve the preferable smooth operation discussed above. Such fasteners engage the rim and the hub of a cutting wheel and abut portions of the knife holder, wherein rotation of the tensioning fasteners towards the hub and rim of the cutting wheel will urge deflection of the knife holder and provide adjustment of the knife relative to the cutting wheel.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]     For a better understanding of the present invention and to show how the same can be carried out in practice, reference will now be made to the accompanying drawings, in which:  
         [0015]      FIG. 1  is a front view of a known type of cutting wheel;  
         [0016]      FIG. 2  is a perspective view of a known knife for a cutting wheel;  
         [0017]      FIG. 3  is an exploded view of the knife illustrated in  FIG. 3 ;  
         [0018]      FIG. 4  is a perspective view of a first embodiment of a knife according to the present invention;  
         [0019]      FIG. 5  is an exploded view of the knife illustrated in  FIG. 4 ;  
         [0020]      FIG. 6  is an exploded perspective view of another embodiment of a knife holder and insert member according to the invention;  
         [0021]      FIG. 7  is sectional side view of the knife illustrated in  FIG. 4 ;  
         [0022]      FIG. 8  is a sectional side view of an embodiment of the recess of the knife holder of the invention;  
         [0023]      FIG. 9  is a perspective view of another embodiment of a knife according to the present invention;  
         [0024]      FIG. 10  is an exploded view of the knife illustrated in  FIG. 9 ;  
         [0025]      FIG. 11  is plan view of a back side of the knife illustrated in  FIG. 9 ;  
         [0026]      FIG. 12  is a perspective view of an embodiment of the tensioning fasteners on a cutting wheel with a knife holder of the invention; and  
         [0027]      FIG. 13  is a plan view of the tensioning fasteners in  FIG. 12  on a cutting wheel with a knife of the invention.  
         [0028]      FIG. 14  is a detailed plan view showing an embodiment of a cutting wheel of the invention having notched portions. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0029]     In accordance with the invention, an embodiment of the inventive knife  50  having an insert member  58  is illustrated in  FIGS. 4 and 5 . The knife  50  comprises a knife holder  54  having a similar construction to the knife holder  18  of  FIGS. 2 and 3  with the added features of a recess  60  extending along at least a portion of the leading side thereof. As a result of the recess  60 , the knife holder  54  defines an first leading edge  61  and a mutually parallel second leading edge  63 . Mounted in the recess  60  is an insert member  58  having a leading edge  59  protruding from leading edges  61 ,  63  of the knife holder  54  and generally contiguous therewith.  
         [0030]     The knife includes a cutting blade  52  that is held against a bevel surface  64  of the knife holder  54  by clamp  56 . The clamp  56  may be attached to the knife holder by a plurality of suitable fasteners that engage keyhole-shaped slots  72  of the clamp  56 . Suitable locating studs may be provided to extend from the knife holder  54  and engage openings  76  in the cutting blade  52  to position the cutting blade  52  on the knife holder  54 . It will be understood, however, that in lieu of the clamp  56 , the cutting blade may be secured to the knife holder solely by fasteners or other known clamping elements available to those skilled in the art.  
         [0031]     The knife holder  54  has a rear edge  66  formed thereon which extends obliquely with respect to the cutting edge  62  of the cutting blade  52 . The knife holder  54  has a hub mounting hole  68  and rim mounting holes  70   a  and  70   b  formed therein for attachment to a hub and rim, respectively, of a cutting wheel. Moreover, the width of the knife holder  54  at the hub mounting end is less than the width of the knife holder  54  at the rim mounting end.  
         [0032]     The recess  60  generally has a length equal substantially to the length of the opposed leading edges  61 ,  63  of the knife holder  54 .  
         [0033]     The insert member  58  preferably defines opposed first and second beveled wear surfaces  82 ,  84  joining to form the leading edge  59  thereof. The beveled wear surfaces  82 ,  84  may conform to the contours of the front and rear surfaces of the knife holder  54  and thus, extend at oblique angles relative to one another. Alternatively, the beveled wear surfaces may be configured so as to serve as a mere extension of the front and rear surfaces of the knife holder. Moreover, the beveled wear surfaces may be shaped so that at least one of the beveled wear surface has a curved profile.  
         [0034]     In another embodiment illustrated in  FIG. 6 , the insert member  65  has opposed end portions with squared edges  67  bordering a central portion  69  thereof defined as a leading bevel. The central portion  69  preferably corresponds to a first bevel  73  of knife holder  71  such that the central portion  69  extends at the same angle as bevel  73  relative to a first surface  75  of the knife holder  128 . While in a preferred embodiment the end portions generally have a rectangular cross-sectional profile, the end portions may have a variety of cross-sectional profiles known to one skilled in the art and the invention is thus not limited to rectangular profiles.  
         [0035]     The wear surfaces of the insert member provide a replaceable artificial leading edge to the knife holder of the invention. When the cutting edge of the cutting blade requires replacement due to chipping, cracking, or other wear factors, the leading edge of the insert member will likely exhibit the same wear and similarly will require replacement. As opposed to replacing the entire knife holder and adjustment of a new knife holder on a cutting wheel, the invention permits replacement of only the cutting blade or the insert member, and therefore removes the necessity of replacing or readjusting the entire knife assembly.  
         [0036]     The insert member  58  may include an identification feature  86  that permits orientation of the insert member relative to the knife holder  54 . In the embodiment shown in  FIG. 5 , the orientation feature  86  comprises a locating hole disposed on the end of the insert member  58  located near the rim mounting holes  70   a  and  70   b  of the knife holder  54 . It will be understood that the orientation feature  86  is not limited to a hole and may be defined by any identification means, such as a notch or an engraving, suitable for demarcating a portion of the insert member.  
         [0037]     Preferably, the insert member has a hardness that will resist cracking, chipping and instead yield and bend upon striking debris. Accordingly, it is desirable that the insert member is constructed from a material that is not too brittle and is sufficiently tough. Moreover, it is desirable that the insert member is corrosion resistant due to its primary application in food processing. While other suitable materials may be used, a preferred construction material is stainless steel, more specifically 410 stainless steel.  
         [0038]      FIG. 7  is an enlarged, sectional side view of the leading portion of the knife  50  including a slightly exaggerated depiction of the recess  60 . The recess  60  includes a rear wall portion  86 , and upper and lower wall portions  88 ,  90 . In a preferred embodiment, the upper and lower wall portions define a tapered clearance progressively increasing in thickness from the leading edges  61 ,  63  to the rear wall portion  86 . The thickness of the taper of the clearance in the preferred embodiment begins at approximately 0.0395 inches at the leading edges  61 ,  63  and increases to 0.0475 inches at the rear wall portion  86 . Preferably, the depth of the recess is 0.3125 inches and the insert member is sized to protrude approximately 0.125 inches from the leading edges  61 ,  63  of the knife holder  54 . In one embodiment, the corners of the recess defined at the junction of the upper and lower walls and the rear wall of the recess may be wire cut so as to have a rounded profile.  
         [0039]     The rear portion  92  of the insert member  58  preferably abuts the rear wall portion  86  of the recess  60 . It will be understood, however, that portions of the upper and lower wall portions  88 ,  90  near the rear wall portion  86  of the recess  60  only minimally or do not clamp the insert member  58 . Accordingly, the insert member  58  is more firmly clamped by the walls  88 ,  90  of the recess  60  near the leading edges  61 ,  63  of the knife holder  54 . Moreover, the rear edges of the insert member  58  do not abut the walls of the recess so as not to chip or bend when inserted into the recess  60 .  
         [0040]     In another embodiment of the recess  60 ,  FIG. 8  shows the lower wall portion  90  of the recess  60  having an indent section  94  located near the rear wall portion  86 . In this embodiment, the indent section  94  is preferably within a range of 0.0008 to 0.0014 inches in depth relative to the portion of the lower wall portion  90  without the indent section  94 . An opposed indent section may also be provided on the upper wall portion  88 , either alone or in combination with the indent section  94  of the lower wall portion  90 .  
         [0041]     In each embodiment, the insert member is precisely positioned within the recess and is snugly received by the recess so as to be held from any shifting along its axis or laterally relative to the rear wall portion. Suitable fasteners may be employed to additionally secure the insert member within the recess and tensioning fasteners, which will be discussed below, may exert pressure against the recess and the insert member to maintain the insert member within the recess. Moreover, pressure exerted by the clamp and the protruding portion of the insert member against the cutting blade forms a mechanical seal, thereby preventing any build-up of debris from food processing operations in the recess.  
         [0042]     The components of the knife of the invention may be configured to accommodate a variety of cutting blades known to those skilled in the art such as a cutting blade having a convexly or concavely curved cutting edge, a cutting edge formed in a series of curves to impart a sinusoidal or “wavy” configuration, or a cutting edge comprised of a series of “V&#39;s” along its length.  
         [0043]     In an embodiment shown in  FIGS. 9-11 , the knife  96  includes knife holder  98  configured to support cutting blade  100  having a cutting edge with a profile  102  comprising a plurality of “V&#39;s” along its length. The knife holder  98  is provided with a recess  104  configured to receive and secure insert member  106 . The insert member  106  includes a profile  108  along a segment thereof along its length complementary to the profile  102  of the cutting blade  100 . Moreover, as depicted in detail in  FIG. 11 , the back surface  110  of the knife holder  98  has a profile  112  that accommodates the profile  102  of the cutting blade  100  and the profile  108  of the insert member  106 .  
         [0044]     A clamp, as illustrated above in connection with the embodiment shown in  FIGS. 4 and 5 , may be employed to secure the cutting blade  100  to a knife holder. The clamp, in similarity to the insert member  106  and knife holder  98 , may be configured with a profile accommodating the shape of the cutting blade  100 .  
         [0045]     As indicated above, the knife of the invention is adapted for use on a cutting wheel of a known food slicing apparatus. Another feature of the invention is the addition of tensioning fasteners that may be provided to adjust a knife holder on a cutting wheel relative to the rim and hub of a known cutting wheel. As exemplified in  FIGS. 12-13 , tensioning fasteners  114  may be provided that extend through and engage through holes  122  of a hub  116  and a rim  118  of a cutting wheel. The through holes  122  preferably correspond to a section near the leading side of a knife holder  120  when mounted to the hub  116  and rim  118  so as to more fully take advantage of adjusting the position of the leading side of knife holder  120 , and subsequently a cutting edge of a cutting blade when installed thereon.  
         [0046]     The tensioning fasteners  114  are arranged to abut a rear surface of the knife holder  120 , whereupon rotation of the tensioning fasteners  114  in one direction, the tensioning fasteners  114  urge deflection of the knife holder  120  relative to the hub  116  and rim  118  of the cutting wheel. Conversely, rotation of the tensioning fasteners  114  in an opposite direction relieves the deflection of the knife holder  120  relative to the hub  116  and rim  118  of the cutting wheel.  
         [0047]     The tensioning fasteners are constructed to include fine threads at fine angles to achieve the preferable, smooth rotation thereof relative to the rim and hub. Moreover, the tensioning fasteners include tapered end portions to prevent excessive wear of both the fasteners themselves and the knife holder.  
         [0048]     The tensioning fasteners permit fine adjustments of the knife holder on a cutting wheel and remove the necessity of disassembling the knife from the rim and hub to achieve a desired adjustment thereof. Moreover, the tensioning screws improve the precision of the adjustability of the knife holder relative to the rim and hub of a cutting wheel since the tensioning fasteners are positioned closely to the leading side of the cutter support segments, and substantially near the cutting edge of the cutting blades mounted on the knife holder.  
         [0049]     In another embodiment best illustrated in  FIG. 14 , a hub  124  and a rim  126  of a cutting wheel in an embodiment of the invention may be provided with depressions  128 ,  130 , respectively, for each knife to be mounted thereon and located on a side of the hub and rim upon which the knife holder  134  is mounted. As shown, the depressions  128 ,  130  radially extend along at least a portion of each hub  124  and rim  126 , and preferably have a depth of 0.015 inches. The depressions may intersect with through holes  136  used to accommodate tensioning fasteners, such as those described in connection with  FIGS. 12 and 13 . Moreover, opposed depressions  128 ,  130  corresponding to each knife holder are preferably radially aligned with one another. One of the purposes behind the depressions is that they facilitate starch cleaning of the rim, hub and each knife holder of a cutting wheel assembly.  
         [0050]     It will be understood that the above described embodiments of the invention may assume a variety of different shapes, sizes and configurations without departing from the scope of the present invention.  
         [0051]     It will be understood that the above described embodiments of the invention are illustrative in nature, and that modifications thereof may occur to those skilled in the art. Accordingly, this invention is not to be regarded as limited to the embodiments or particular uses disclosed herein, but are to be limited only as defined in the appended claims.