Abstract:
A method and apparatus by which potatoes and other elongate food product can be properly oriented and stabilized during a slicing operation performed by a cutting device having a horizontal cutting plane. The apparatus includes a passage extending downwardly toward the cutting device and defining an opening in proximity to the cutting device, splines or other suitable features disposed along a first portion of the passage and oriented substantially parallel to the passage, and means for applying a force on a food product traveling downward through the passage so as to urge the product into contact with the splines during engagement with the cutting device.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   Not applicable. 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH 
   Not applicable. 
   BACKGROUND OF THE INVENTION 
   (1) Field of the Invention 
   The present invention generally relates to cutting methods and equipment. More particularly, this invention relates to a method and apparatus for delivering food product to a cutting device having a horizontal cutting plane, by which the product is properly oriented and stabilized to produce a sliced product of uniform thickness. 
   (2) Description of the Related Art 
   Various types of equipment are known for slicing, shredding and granulating food products such as vegetables, fruits and meat products. A particular example is slicing equipment adapted for cutting root vegetables, such as potatoes, into thin slices suitable for making potato chips (also known as potato crisps). A widely used machine for this purpose is commercially available from the assignee of the present invention under the name Urschel Model CC. The Model CC is a centrifugal-type slicer capable of producing uniform slices, strip cuts, shreds and granulations of a wide variety of food products at high production capabilities. The centrifugal operation of the Model CC does not provide for orienting an elongate product so that its longitudinal axis is perpendicular to the cutting blades. Therefore, when used to produce potato slices for potato chips, the Model CC requires the use of substantially round potatoes in order to produce the desired circular chip shape with a minimum amount of scrap. 
   Because potatoes tend to have an elongated shape, round potatoes of the type that can be processed with the Model CC typically cost more, generally as a result of the special potato varietals and/or farming techniques required to produce a rounder shape. In view of this additional cost, it would be desirable if potato chips with the desired circular shape could also be produced from potato varietals with elongate shapes. It is also of ongoing interest in the industry to achieve greater chip consistency in terms of shape and thickness, while minimizing scrap. 
   The TranSlicer 2000® is a slicing apparatus that has found wide use for slicing elongate food products. Commercially available from the assignee of the present invention and disclosed in U.S. Pat. No. 6,148,702 to Bucks, the TranSlicer 2000® employs a cutting wheel disposed in a vertical plane and rotated on a horizontal axis, with radial cutting blades mounted between a hub and an annular-shaped rim. A notable example of a cutting wheel suitable for use with the TranSlicer 2000® is disclosed in commonly-assigned U.S. Pat. Nos. 5,992,284 and 6,148,709 to Bucks. A conveyor or other suitable device is required to deliver product horizontally to the cutting wheel. The cutting operation performed by the TranSlicer 2000® is generally limited to the hemisphere of the cutting wheel in which the blades are traveling downward, because attempting to cut a product as the blade travels upward tends to lift the product off the conveyor. 
   The TranSlicer 2000® is well suited for slicing, shredding and granulating a wide variety of fruits, vegetables and meat products, including the slicing of elongate potatoes for potato chip production. However, a difficulty arises when attempting to produce crinkled slices (slices having a corrugated shape when viewed edgewise) or “V-slices” (similar to crinkled but with relative sharp peaks and valleys when viewed edgewise), both of which are common shapes for potato chips. As noted above, the TranSlicer 2000® is generally limited to a cutting operation performed in the hemisphere of the cutting wheel in which the blades are traveling downward. Even when being sliced in a downward direction, an elongate product can rotate slightly about its longitudinal axis for lack of a means for positively holding the product while engaged with the blade. While this aspect is of no significance when slicing most elongate products to produce flat slices, any rotation of an elongate potato that occurs when attempting to produce crinkled or V-slice chips results in the grooved pattens on opposite surfaces of a chip being misaligned, which can be aesthetically undesirable, cause uneven cooking, and produce shredded product if the chips are sliced sufficiently thin, e.g., on the order of about two mm or less. 
   In view of the above, it would be desirable if an improved method and apparatus were available that enabled potatoes and other elongate products to be properly oriented and stabilized during a slicing operation. Such a method and apparatus would preferably be suitable for producing crinkled and V-slice potato chips while preferably achieving high production capabilities and minimizing scrap. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention provides a method and apparatus by which potatoes and other elongate food products can be properly oriented and stabilized during a slicing operation, while also enabling high production capabilities and minimizing scrap. The method and apparatus of this invention particularly provide for delivering food product to a cutting device having a horizontal cutting plane, which can therefore make use of gravity to deliver the product to the cutting device, but requires that the product is properly oriented and stabilized after traveling in a downward direction to the cutting device. 
   The apparatus of this invention includes a passage extending downwardly toward the cutting device and defining an opening in proximity to the cutting device, splines or other suitable guide means disposed along a first portion of the passage and oriented substantially parallel to the passage, and means for applying a force on a food product traveling downward through the passage so as to urge the product into contact with the splines during engagement with the cutting device. Accordingly, the method of this invention entails the delivery of food product to the cutting device through the passage, and applying a sufficient force on the product as it travels downward through the passage so that the orientation of the product remains substantially constant within the passage by the splines during engagement with the cutting device. 
   According to a first preferred aspect of the invention, the force is applied to the product by at least two fluid jets flowing across the passage toward the first portion, such that the fluid jets impact the product as the product travels downward through the passage. According to another preferred aspect of the invention, elongate products are delivered to the passage by means capable of separating and longitudinally aligning the products with the passage, so that the elongate products enter the passage with their longitudinal axes roughly parallel to the passage. 
   In view of the above, it can be seen that a significant advantage of this invention is that potatoes and other elongate food products can be properly oriented and stabilized during a slicing operation by delivering the product in a downward direction to a substantially horizontal cutting device. Orientation and stabilization of elongate product are achieved by applying a sufficient lateral force on the product to maintain the product in contact with splines or other features capable of maintaining the orientation of the product within the passage. Another significant advantage of this invention is that the use of a substantially horizontal cutting device allows the entire cutting plane to be used in performing the cutting operation, since the cutting action does not have any tendency to lift or otherwise disorient the product during the cutting operation. As such, the method and apparatus of this invention can be used to achieve high production capabilities while minimizing scrap. 
   Other objects and advantages of this invention will be better appreciated from the following detailed description. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side view of a product delivery and slicing system in accordance with a preferred embodiment of this invention. 
       FIG. 2  is a plan view of the delivery and slicing system of FIG.  1 . 
       FIG. 3  is a plan view of a delivery tube and cutting wheel of the delivery and slicing system of FIG.  1 . 
       FIG. 4  is a plan view of the delivery tube of  FIG. 3 , and shows a food product traveling through the tube toward the cutting wheel beneath the tube. 
       FIG. 5  is a cross-sectional view of the delivery tube and a blade of the cutting wheel of FIG.  3 . 
       FIG. 6  is a cross-sectional view corresponding to  FIG. 5 , and shows food product traveling downward through the tube into engagement with a blade of the cutting wheel. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIGS. 1 and 2  are side and plan views, respectively, of processing unit  10  for producing sliced food product in accordance with the present invention. The processing unit  10  includes a system  14  for delivering food product  32  to an apparatus  12  with which the slicing operation is performed. The apparatus  12  generally comprises a slicing unit  20  and a frame  24  by which the slicing unit  20  is mounted and supported above the surrounding floor. The slicing unit  20 , shown with its interior visible in  FIG. 1 , includes an enclosure  26 , an internally-mounted electric motor  28 , and a horizontal cutting wheel  30  housed within the enclosure  26  and driven by the motor  28 . The enclosure  26  defines a chute from whose lower end the sliced food product exits the slicing unit  20 . The frame  24  preferably houses the electrical wiring for powering the motor  28  and controls for operating the processing unit  10 . 
   The product delivery system  14  includes a conveyor  16  and flexible tubes  18  that deliver the product  32  to a number of feed tubes  22  mounted to the top of the slicing unit  20 . The feed tubes  22  feed the product  32  to the cutting wheel  30  within the slicing unit  20 . In  FIG. 2 , portions of the flexible tubes  18  are omitted for clarity, providing a plan view of the feed tubes  22 . Each of the feed tubes  22  is represented in the Figures as having a circular cross-sectional shape, though other shapes are possible, including tubes with square-shaped cross-sections. Each feed tube  22  provides a complete enclosure surrounding the product  32  as it is presented to the cutting wheel  30  through an opening  54  ( FIGS. 5 and 6 ) defined at the lower end of each tube  22 . However, as will become apparent from the following discussion, the feed tubes  22  are not required to completely surround the product  32 . While four feed tubes  22  are shown in  FIG. 2 , it is foreseeable that any number of tubes  22  could be used, limited only by the surface area of the cutting wheel  30  relative to the size of the feed tubes  22 . 
   The cutting wheel  30  can be of various designs, a preferred design being the Microslice® cutting wheel disclosed in U.S. Pat. Nos. 5,992,284 and 6,148,709. As depicted in  FIGS. 3 and 4 , the cutting wheel  30  can be seen to generally comprise a number of radial blades  34  mounted between a hub  36  and an annular-shaped rim  38 . In  FIGS. 5 and 6 , the blades  34  are seen as being closely spaced in the circumferential direction, with the cutting (leading) edge  40  of each blade  34  projecting above the trailing edge  42  of the preceding blade  34 , thereby establishing the thickness of product slices  44  ( FIG. 6 ) produced by the cutting wheel  30 . It is worth noting that the blades  34  shown in  FIGS. 3 through 6  are depicted as having corrugated cutting edges  40  that produce crinkle slices, i.e., a corrugated or sinusoidal shape with rounded peaks and valleys when viewed edgewise. Alternatively, the blades  34  could have flat cutting edges to produce flat slices, or V-shaped cutting edges to produce “V-slices” with relative sharp peaks and valleys when viewed edgewise. If the blades  34  are equipped with corrugated or V-shaped cutting edges  40 , the radial placement of each blade  34  relative to the preceding blade  40  will determine the appearance of the slices. If the peaks and valleys of the blades  34  are aligned, each peak on one surface of a slice will correspond to a valley on the opposite surface of the slice, such that the thickness of the slice is substantially uniform. However, if the peaks and valleys of the adjacent blades  34  are not aligned, the slices produced will be characterized by alternating thick and thin-walled sections (known as “phase shift”), and if sufficiently misaligned the product  32  may be shredded by the cutting wheel  30 . Whether slices or shredded product are desired will depend on the intended use of the product. As will become apparent from the following discussion, the present invention enables the type of product desired to be accurately and reliably determined by the cutting wheel  30 , instead of randomly determined by changes in the orientation of the product during the cutting operation. 
   From  FIGS. 1 and 2 , it can be seen that the delivery system  14  singulates and orients the product  32  before delivering the product  32  in a substantially vertical direction to the feed tubes  22 , which are also shown as being vertically oriented. The generally vertical presentation of the product  32  is due to the substantially horizontal orientation of the cutting wheel  30 . While the feed tubes  22  are shown as being oriented at about 90 degrees to the surface (plane) of the cutting wheel  30 , it is foreseeable that other orientations could be used, depending on the angle at which cuts are desired through the product  32 . However, the cutting wheel  30  is preferably disposed in the horizontal plane, and the feed tubes  22  are disposed at an angle of about 15 to about 90 degrees, preferably about 90 degrees, to the cutting wheel  30 . 
   While horizontal cutting wheels with vertical product delivery are known in the prior art, product orientation typically is of importance only if the product  32  is elongate, as represented in the Figures. Product orientation becomes of particular concern if the slicing operation is to produce very thin slices, e.g., on the order of about three mm or less, and a consistent peripheral shape is desired for the slices, such as a true cross-section of the product  32  or a consistent diagonal (bias) slice through the product  32 . Finally, product stability becomes critical if crinkled or V-slices are desired, because any rotation of the product  32  about its longitudinal axis or lateral movement of the product  32  (i.e., perpendicular to the product&#39;s longitudinal axis) will result in misalignment of the peaks and valleys in the opposite surfaces of the slices, resulting in a product having a crosshatched (lattice) appearance that may include patterns of holes if the slices are sufficiently thin. The slicing of elongate potatoes to produce round crinkle or V-slice chips is a primary example of these circumstances, and therefore will be referred to throughout this description. However, round potatoes and other food products with various shapes, round, elongate and even rectilinear, can be handled with the processing unit  10  of this invention. 
   According to the invention, product stability during the cutting operation is achieved within the feed tubes  22  as a result of splines  46  or other suitable surface features present on the interior surface of a wall  48  of each feed tube  22 , so as to project into a feed passage  50  defined by the tube  22 . As shown, the splines  46  are oriented longitudinally to the axis of the tube  22 , such that the splines  46  promote and maintain the orientation of the product  32  relative to the longitudinal axis of the tube  22 . As seen in  FIG. 4 , product  32  with diameters smaller than the feed passage  50  could become misaligned within the passage  50  unless the product  32  is forced to remain in contact with the splines  46  throughout its travel through the passage  50 . For this purpose, the feed tubes  22  are shown as being equipped with fluid jets  52  emitted from nozzles  58  located in a wall  62  of the tube  22  opposite the splines  46 . Water is the preferred fluid for the jets  52 , though it is foreseeable that other fluids, including liquids and gases, could be used. Water is represented in  FIGS. 3 through 6  as being delivered to each nozzle  58  through a hose  60 , though a manifold or other fluid handling technique could be used to deliver the fluid to the nozzles  58 . 
   According to a preferred aspect of the invention, the fluid jets  52  combine to apply a lateral force to the product  32  that is sufficient to push the product  32  into contact with the splines  46  and thereafter cause the product  32  to remain in contact with the splines  46  while being sliced with the cutting wheel  30 , as depicted in FIG.  6 . As a result, the product  32  is inhibited from rotating about its longitudinal axis. According to another preferred aspect of the invention, multiple fluid jets  52  are employed to inhibit lateral movement of the product  32 . For this purpose, two sets of two converging jets  52  are preferred, as shown in  FIGS. 3 through 6 , though any number of jets could be used, and not necessarily in pairs. The pair of fluid jets  52  in a given set are preferably coplanar and flow in a downward direction, as seen from the side views of  FIGS. 5 and 6 . One set of jets  52  is located directly above the other set, as can be discerned from the plan views of  FIGS. 3 and 4 . The jets  52  are preferably oriented at an acute angle to horizontal (and therefore to the cutting wheel  30 ) of up to about forty-five degrees, though it is foreseeable that the jets  52  could be oriented at other angles to horizontal, or horizontal and therefore parallel to the cutting wheel  30 . Orienting the jets  52  to project at an angle toward the cutting wheel  30  is preferred to assist in stabilizing the product  32  while undergoing cutting by the blades  34 , as well as assisting in feeding the product  32  downward through the tubes  22 . In practice, an angle of about 30 degrees from horizontal in a direction toward the cutting wheel  30  has produced excellent results. 
   In  FIG. 3 , the pairs of jets  52  are depicted as converging to intersect at the opposite wall  48  of the feed tube  22 . However, it is foreseeable that the jets  52  of a given pair could intersect some distance away from the tube wall  48 , or not intersect at all. Of primary interest is that the jets  52  converge to inhibit lateral movement of the product  32 , and thus promote the stability of the product  32  while within the passage  30  and particularly while the product  32  is subject to the forces applied by the blades  34  during the cutting operation. For this purpose, the jets  52  are preferably oriented to have an included angle of more than zero to less than 180 degrees, with a suitable angle between the jets  52  being up to about ninety degrees. In practice, an angle of about 30 degrees between the jets  52  has worked well. In addition, the stability of the product  32  is believed to be promoted if the jets  52  intersect at a point on the wall  48  of the tube  22  directly above the point at which the trailing edges  42  of the blades  34  last pass beneath the opening  54  of the tube  22  above the cutting wheel  30 , as apparent from FIG.  3 . 
   The force required to be applied to the product  32  in order to maintain the product  32  in contact with the splines  46  will depend in part on the mass and density of the product  32  and the speed of the blades  34 . In practice, elongate potatoes of a size typical size for use in producing potato chips can be firmly held by four water jets  52  arranged as shown in  FIGS. 3 through 6 , where each jet  52  is discharged at a pressure of about 20 to about 30 psi (about 1 to about 2 bar) from a nozzle  58  having an orifice diameter of about 6.3 mm. Under these conditions, the total water flow rate through each tube  22  is about 10 gallons per minute (about 40 liters/minute). 
   While the stabilizing force desired for cooperation with the splines  46  has been described as being generated by fluid jets  52 , it is foreseeable that other means for applying a generally lateral force on product  32  could be used, such as springs, bladders, spring-loaded paddles or rollers, and brushes. Furthermore, because the product  32  is retained within the passage  50  by the splines  46  and not any wall portion (e.g., wall  48 ) of the feed tube  22  (for example, see FIG.  6 ), it is possible that the passage  50  could be defined simply by a number of splines  46  or other longitudinal members and a force-applying means opposite the splines  46 . However, in a preferred embodiment, each passage  50  is defined by a feed tube  22 , and the periphery of each passage  50  is entirely enclosed by the tube walls  48  and  62  so that the fluid used in the jets  52  is contained and flows downwardly through the cutting wheel  30  with the sliced product. While suitable internal diameters for the tubes  22  will depend on the size of the particular product  32 , a suitable diameter for tubes  22  used to deliver potatoes is about 3.5 to about 4 inches (about 9 to about 10 cm). Splines  46  for a tube  22  of this diameter are preferably spaced about 25 to about 30 degrees apart, and are present around about one-half of the circumference of the tube  22 . Suitable dimensions for the splines  46  are a width of about 0.093 inch (about 2.4 mm) and a height of about 0.090 inch (about 2.3 mm). 
   In view of the importance of maintaining proper alignment of the product  32  within the feed tubes  22 , it can be appreciated that proper presentation of the product  32  to the tubes  22  is also important. As depicted in  FIGS. 1 and 2 , the conveyor  16  of the product delivery system  14  preferably singulates and orients the elongate product  32  so that the longitudinal axis of each product  32  is essentially parallel to the flexible tube  18  that it enters for delivery to one of the feed tubes  22 . This aspect of the invention is shown as being achieved by a conveyor with multiple lanes  56 , each dedicated to delivering product  32  to one of the flexible tubes  18 . A particularly suitable conveyor  16  for this purpose is an electromagnetic vibratory conveyor commercially available under the name Impulse from Key Technology, Inc. However, other devices for singulating product, elongate, round or otherwise, could be used. 
   While the invention has been described in terms of a preferred embodiment, it is apparent that other forms could be adopted by one skilled in the art. For example, the physical configuration of the processing unit  10 , including the apparatus  12 , delivery system  14 , and slicing unit  20 , could differ from that shown, and the physical and functional specifications of the invention could differ from those discussed. Therefore, the scope of the invention is to be limited only by the following claims.