Patent Publication Number: US-2007095216-A1

Title: Snipper knife

Description:
BACKGROUND  
      The present invention relates to a snipping apparatus for processing elongated vegetable products, such as beans and the like, and in particular, a snipper knife for removing an end portion of a vegetable.  
      Snipping apparatus are used to remove the ends from beans prior to canning or other packaging of the beans. A widely used system includes a frame and a rotating drum structure with a mass of beans moving from one end of the drum to another end. The periphery of the drum is slotted, and the slots are sized and shaped to permit projection of one end of a bean through the slot while preventing the entire bean from falling through the slot. A plurality of metal snipper knives are mounted to engage the peripheral surface of the drum. As the drum rotates, the snipper knives cut the ends of the beans that protrude through the slots. Recently, some snipping apparatus have incorporated drums made of polycarbonate material. Metal snipper knives can cause wear and damage to the polycarbonate drums.  
      The snipper knives are mounted against the drum using a knife holder assembly. A plurality of mounting rods are attached to the apparatus frame, which extend along a length of the drum parallel to the peripheral surface. Each knife is attached to a resilient rod, which is attached to one of the mounting rods. In such knife holder assemblies, additional components are required to attach the resilient rod to the knife, which increases the cost of the knife holder assembly and time required for replacing snipper knives.  
     SUMMARY  
      In one embodiment, the invention provides a knife for a snipping apparatus including a knife body having two side edges and a top edge, wherein the two side edges define cutting edges angularly disposed on the knife body. The knife body is formed of a non-metallic material.  
      In another embodiment, the invention provides a knife for a snipping apparatus. The knife includes a knife body having two side edges and a top edge, wherein the two side edges define cutting edges angularly disposed on the knife body. An attachment means is formed in a top surface of the knife body, the attachment means configured and adapted for receiving a rod. The attachment means includes a channel formed in the top surface of the knife body, the channel being substantially aligned with a longitudinal axis of the knife body and positioned proximate a corner between the two side edges, and a bore formed in the top surface of the knife body and aligned substantially parallel to the top edge of the knife body.  
      In another embodiment, the invention provides a knife assembly for a snipping apparatus. The knife assembly including an assembly holder configured and adapted for coupling to a mounting rod, flexible means having a first end coupled to the assembly holder and a second end, and a knife body having two side edges and a top edge. The two side edges define cutting edges angularly disposed on the knife body and the knife body is formed of a non-metallic material. Attachment means are formed in a top surface of the knife body, the attachment means configured and adapted for receiving the second end of the flexible means.  
      In yet another embodiment, the invention provides a snipping apparatus includes a frame having an inlet end and an outlet end, a rotatable drum mounted in the frame and having a slotted sidewall, and a plurality of mounting rods fixed relative to the frame and positioned adjacent the sidewall of the drum. The mounting rods extend between the inlet end and the outlet end and are aligned generally parallel to a longitudinal axis of the drum. The snipping apparatus also includes a plurality of resilient rods having a first end a first end coupled to one of the mounting rods and a second end. A plurality of snipper knives are each coupled to the second end of one of the resilient rods. Each snipper knife has at least one cutting edge and is formed of a non-metallic material. The cutting edge of the snipper knives engage the drum.  
      In still another embodiment, the invention provides an attachment system for use with a snipping apparatus, the attachment system for facilitating attachment of a knife to a knife assembly. The attachment system includes a body member having a top surface, a forward edge and a rearward edge. A channel is formed in the body member, the channel being aligned substantially perpendicular with the forward edge and positioned proximate the rearward edge. A bore is formed in the body member, the bore being aligned substantially parallel to the top edge of the knife body and positioned forward of the channel.  
      Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a side view of a bean snipping apparatus illustrating a snipper knife for use with the apparatus.  
       FIG. 2  is a top view of a snipper knife embodying the invention with an attached knife rod.  
       FIG. 3  is a top perspective view of the snipper knife shown in  FIG. 2 .  
       FIG. 4  is a bottom perspective view of the snipper knife shown in  FIG. 2 .  
       FIG. 5  is a top view of the snipper knife shown in  FIG. 2 .  
       FIG. 6  is a perspective view of another embodiment of a snipper knife for use with the snipping apparatus shown in  FIG. 1 . 
    
    
      Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.  
     DETAILED DESCRIPTION  
       FIG. 1  illustrates a snipping apparatus  10  for processing elongated vegetable products, such as beans and the like, and removing an end portion of each bean. In particular, the snipping apparatus  10  includes a plurality of non-metallic snipper knives  14  for cutting the end portions of the beans.  
      The snipping apparatus  10  includes a frame  18  having an infeed chute  22  at an inlet end  26  and a discharge chute  30  at an outlet end  34 . The frame  18  is supported by legs  38  that rest upon a support surface and space the frame  18  above the support surface. The inlet end  26  of the frame  18  includes an inlet end wall  42  that defines an opening (not shown) for receiving the infeed chute  22 . Similar to the inlet end  26 , the outlet end  34  of the frame  18  includes an outlet end wall  46  that defines an opening (not shown) for receiving the discharge chute  30 . The frame  18  is preferably made of stainless steel or another suitable material for food processing applications.  
      A rotatable drum  50  is mounted in the frame  18  and is configured to transport beans received in the snipping apparatus  10  from the inlet end  26  to the outlet end  34  of the frame  18 . Generally, the drum  50  is positioned at an incline relative to the support surface to permit the beans to travel from the inlet end  26  to the outlet end  34  of the apparatus  10 . In the illustrated embodiment, the inlet end  26  of the frame  18  is spaced further from the support surface than the outlet end  34  of the frame  18  to create the inclined drum  50 , i.e., the frame leg at the inlet end  26  of the frame  18  is taller than the frame leg at the outlet end  34 .  
      The drum  50  includes an inlet end wall  54  proximate the inlet end wall  42  of the frame  18  and an outlet end wall  58  proximate the outlet end wall  46  of the frame  18 . The infeed chute  22  communicates with an opening (not shown) in the inlet end wall  54  to deposit food product in the drum  50  and the discharge chute  30  communicates with an opening (not shown) in the outlet end wall  58  to receive food product from the drum  50 . The drum  50  includes a generally cylindrical and perforate sidewall  62  that extends between the inlet end wall  54  and the outlet end wall  58 . The sidewall  62  includes a plurality of elongated slots  66  that extend completely therethrough. The slots  66  are sized and configured to permit ends of the beans to pass through the slots  66  to the exterior of the drum  50 , while preventing the entire bean from falling out of the drum  50  through the slots  66 .  
      Although not shown in  FIG. 1 , it should be readily apparent to those of skill in the art that the drum  50  includes means for facilitating the transfer the beans from the inlet end  26  to the outlet end  34 , such as baffles, partitions, or the like. Further, the snipping apparatus  10  may include a cover that mates with the frame  18  to substantially enclose the drum  50 .  
      A plurality of mounting rods  70  are coupled to the frame  18  and extend between the inlet end wall  42  and the outlet end wall  46  of the frame  18 . The mounting rods  70  are aligned generally parallel to a longitudinal axis  72  of the drum  50 . The mounting rods  70  are arranged around the circumference of the drum  50  except an uppermost portion of the drum  50 , although in a further embodiment, the mounting rods  70  may be arranged about the entire circumference of the drum  50  or other portions of the drum  50 . In the illustrated embodiment, the mounting rods  70  are fixed relative to the frame  18 , however, in another embodiment, the mounting rods  70  may be oscillated to thereby oscillate the snipper knives  14  back and forth relative to the drum  50 .  
      A plurality of knife holder assemblies  74  are attached to each mounting rod  70  and extend along the length of the drum  50 . The knife holder assemblies  74  are spaced apart equidistantly. Each knife holder assembly  74  includes a clamp  78  (or assembly holder), a resilient rod  82 , and a snipper knife  14 . The clamp  78  is mounted to the mounting rod and includes a pair of plate members  86  that capture the mounting rod  70 . The resilient rod  82  includes a first end  90  coupled to the clamp  78  and a second end  94  coupled to the snipper knife  14  (shown in  FIG. 2 ). In the illustrated embodiment, the resilient rod  82  is formed by a semi-flexible metal rod that biases the snipper knife  14  against the drum  50  such that the snipper knife  14  engages the drum  50 . In further embodiments, other resilient flexible means may be used to couple the snipper knives  14  to the clamps  78 , such as a leaf spring.  
       FIGS. 2-5  illustrate the snipper knife  14  shown in  FIG. 1 . The snipper knife  14  includes a knife body  98  having a generally triangular shape. The knife body  98  has a top surface  102 , a bottom surface  106 , a top edge  110  and first and second side edges  114 ,  118 . The first and second side edges  114 ,  118  extend from opposite ends of the top edge  110  and intersect at a bottom corner  122  of the knife body  98 . The first and second side edges  114 ,  118  define cutting edges angularly disposed on the knife body  98 . In the illustrated embodiment, a hollow portion  126  is formed in the knife body  98  and is positioned adjacent the top edge  110  between the two side edges  114 ,  118 . The bottom surface  106  of the knife body  98  is generally concave such that a center portion  130  of the bottom surface  106  is recessed from the sidewall  62  of the drum  50  ( FIG. 1 ), which reduces friction and wear between the snipper knife  14  and the drum  50 .  
      An attachment system  134  is formed in the top surface  102  of the knife body  98  for attaching the resilient rod  82  to the snipper knife  14 . The attachment system  134  includes a channel  138 , a pair of bores  142 A, and recess portions  146 A- 146 D. The channel  138  is formed along a longitudinal axis  150  of the knife body  98  and extends from the bottom corner  122 . Two sidewalls  154 ,  158  define the channel  138  and provide a friction fit for retaining a portion of the resilient rod  82  within the channel  138  ( FIG. 2 ). In general, the longer the channel  138 , the more secure an attachment between the resilient rod  82  and the snipper knife  14 . The top surface  102  of the knife body  98  includes a central area  162  forward of the channel  138 . The recessed portions  146 A- 146 D surround all four sides of the central area. The top surface  102  includes a pair of arches  166 A,  166 B that extend over the forward most recessed portion  146 A to define the pair of bores  142 A,  142 B.  
      As shown in  FIG. 2 , the second end  94  of the resilient rod  84  is substantially J-shaped. The main portion of the resilient rod  82  is received within the channel  138 . A first section  94 A and a second section  94 B of the second end  94  are positioned within the rearward most recessed portion  146 C and the first side recessed portions  146 B, respectively, of the attachment system  134 . A third section  94 C of the second end  94 , which defines a free end of the resilient rod  82 , passes through the two bores  142 A,  142 B. The third section  94 C has a length sufficient to prevent the resilient rod  82  from becoming detached from the snipper knife  14  during use.  
      In a further embodiment, the second end  94  of the resilient rod  82  may be reversed such that the second section  94 B is positioned within the opposite side recessed portion  146 B and the third section  94 C passes through the two bores  142 A,  142 B in an opposite direction. In the illustrated embodiment, the attachment system  134  is integrally formed in the top surface  102  of the knife body  98 , which in combination with the resilient rod  82  and the configuration of the attachment system  134  eliminates the need for additional components to secure the resilient rod  82  to the snipper knife  14 . It should be readily apparent to those of skill in the art that other configurations of the attachment system integral with the top surface  102  of the knife body  98  may be used for securing the resilient rod  82  to the snipper knife  14 .  
      In the illustrated embodiment, the snipper knife  14  is formed from a filled plastic material by injection molding. In a further embodiment, the snipper knife  14  may be formed from other non-metallic materials, including a ceramic material, plastics, polymers, a polyethylene terephthalate (PET) being 30% glass filled, a 30% nylon 6/6 material, or a 40% nylon 6/6 material. The snipper knife  14  may also be formed using other known fabrication methods, such as by machining a solid block, thermo-forming, vacuum-forming, casting, or other known means. Use of a non-metallic material to form the snipper knife  14  reduces the cost of the snipper knife  14  because of lower raw material costs, as well as lower fabrication costs as the knife  14  is no longer stamped and sharpened. Further, use of a non-metallic knife  14  results in less wear and damage to the drum  50  of the snipping apparatus  10 . In some embodiments, the non-metallic material may increase the use life of the snipper knife  14 . In another embodiment, some portions of the snipper knife  14  are formed from metallic material, such as stainless steel, while the rest of the knife  14  is formed from non-metallic material. For example, the cutting edges  114  and  118  are formed from stainless steel and the remainder of the knife body, including the attachment system  134  is formed from plastic.  
      In a preferred embodiment, the snipper knife  14  has a width of about 4.5 inches along the top edge  102 , an overall length of about 6.5 inches, and a thickness of about 1 inch at a thickest portion of the knife body  90 , generally where the attachment system  134  is located. Further, the knife body  98  generally forms an isosceles triangle. It should be readily apparent to those of skill in the art that the snipper knife  14  may be smaller or larger, or may have other triangular shapes or non-triangular shapes.  
      Prior to operation of the snipping apparatus  10 , the knife holder assemblies  74  are mounted to the mounting rods  70  such that the snipper knives  14  are biased against the sidewall  62  of the drum  50 . During operation, the drum  50  rotates to transfer beans from the inlet end  26  of the snipping apparatus  10  to the outlet end  34 . End portions of the beans project through the slots  66  in the sidewall  62  of the drum  50 . As the drum  50  rotates and the end portions pass the snipper knives  14 , the cutting edges  114 ,  118  of the snipper knives  14  cut off the end portions of the beans.  
      When it is necessary to replace worn snipper knives  14 , an operator detaches the snipper knife  14  from the resilient rod  82  by removing the rod  82  from the channel  138  of the attachment system  134  and sliding the third section  94 C of the rod  82  out of the bores  142 A,  142 B. A new snipper knife  14  is then attached to the resilient rod  82  using the attachment system  134  by sliding the third section  94 C of the rod  82  into the bores  142 A,  142 B and fitting the main portion of the rod  82  within the channel  138 . The attachment system  134  does not include additional components to secure the snipper knife  14  to the resilient rod  82 , nor does the resilient rod  82  need to be removed from the mounting rod  70  at the clamp to replace the snipper knife  14 . Therefore, the present invention snipper knife  14  can be replaced more efficiently, an estimated five times faster, and is less costly to change out, as compared to prior art knives and knife holder assemblies.  
       FIG. 6  illustrates another embodiment of a snipper knife for use with the snipping apparatus  10 . A snipper knife  170  includes a knife body  174  having a generally triangular shape. The knife body  174  has a top surface  178 , a concave bottom surface (not shown), a top edge  182  and first and second side edges  186 ,  190 . The first and second side edges  186 ,  190  extend from opposite ends of the top edge  182  and intersect at a bottom corner  194  of the knife body  174 . The first and second side edges  186 ,  190  define cutting edges angularly disposed on the knife body  174 .  
      An attachment system  198  is formed in the top surface  078  of the knife body  174  for attaching the resilient rod (not shown) to the snipper knife  170 . The attachment system  198  includes a channel  202 , a bore  206 , and recessed portions  210 A- 210 C. The channel  202  has an open top and is formed along a longitudinal axis  214  of the knife body  174 . Two sidewalls  218 ,  222  define the channel  202  and provide a friction fit for retaining a portion of the resilient rod within the channel  202 . In general, the longer the channel  202 , the more secure an attachment with the resilient rod. The top surface  178  of the knife body  174  includes a central area  224  forward of the channel  202 . The recessed portions  210 A- 210 C surround three sides of the central area  224 . The bore  206  is formed within the top surface  178  of the knife body  174  and along a fourth side of the central area  224 . In the illustrated embodiment, the bore  206  is positioned between the central area  224  and the top edge  182  of the knife body  174 , and is aligned generally perpendicular to the longitudinal axis  214  of the knife body  174 . To attach the resilient rod to the snipper knife  170 , the third section of the rod ( FIG. 2 ) passes through the bore  206  of the attachment system  198  and the main portion of the rod ( FIG. 2 ) is press fit within the channel  202 . The first section and the second section of the rod are positioned within the rearward most recessed portion  210 A and one of the side recessed portions  210 B,  210 C, respectively, of the attachment system  198 .  
      In the illustrated embodiment, the attachment system  198  is integrally formed in the top surface  178  of the knife body  174 , which in combination with the resilient rod and the configuration of the attachment system  198  eliminates the need for additional components to secure the resilient rod to the snipper knife  170 . It should be readily apparent to those of skill in the art that other configurations of the attachment system integral with the top surface  178  of the knife body  174  may be used for securing the resilient rod to the snipper knife  170 .  
      In the illustrated embodiment, the snipper knife  170  is formed from a filled plastic material by machining a solid block of material. In a further embodiment, the snipper knife  170  may be formed from other non-metallic materials, including, but not limited to, a ceramic material, plastics, polymers, a polyethylene terephthalate (PET) being 30% glass filled, a 30% nylon 6/6 material, or a 40% nylon 6/6 material. The snipper knife may also be formed using other known fabrication methods, such as injection molding, thermo-forming, vacuum forming, casting or other known means. In another embodiment, some portions of the snipper knife  170  are formed from metallic material, such as stainless steel, while the rest of the knife  170  is formed from non-metallic material. For example, the cutting edges  186  and  190  are formed from stainless steel and the remainder of the knife body, including the attachment system  198  is formed from plastic. The snipper knife  170  shown in  FIG. 6  is more durable and heavier than presently used snipper, which includes the hollow portion  126 . The heavier snipper knife has more inertia when snipping, and therefore is more gentle to the resilient rod and cuts the bean closer with less force on the rod.  
      Various features and advantages of the invention are set forth in the following claims.