Patent Publication Number: US-9888696-B2

Title: Automated product profiling apparatus and product slicing system using the same

Description:
RELATED APPLICATIONS 
     The present application is a continuation of co-pending U.S. patent application Ser. No. 13/504,008, filed Apr. 25, 2012, which is 371 nationalization application of PCT application no. PCT/US2010/054152, filed Oct. 26, 2010, which claims the benefit of U.S. Provisional Patent Application No. 61/255,458, filed Oct. 27, 2009, all of which are incorporated by reference herein in their entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to an apparatus for determining the profile of a product that is to undergo a subsequent physical process. The subsequent physical process is one in which the product profile is needed to insure proper processing of the product. 
     BACKGROUND OF THE INVENTION 
     In one embodiment disclosed herein, the specific subsequent physical process includes slicing the product into individual slices on a slicing machine. Such slicing machines are principally, but not exclusively, used for slicing food products such as cheese, meat and pressed or molded meat products. 
     Food articles can be sliced on high speed slicing machines such as disclosed in U.S. Pat. Nos. 5,628,237 or 5,974,925 or as commercially available as the FX180® slicer available from Formax, Inc. of Mokena, Ill., USA. Food articles can also be sliced on high speed slicing machines such as disclosed in U.S. patent application Ser. No. 12/255,623, or as commercially available as the PowerMax4000™ slicing system available from Formax, Inc. U.S. Pat. Nos. 5,628,237 or 5,974,925 and U.S. Published Application US2009/0151527 are each hereby incorporated by reference except where inconsistent with the present disclosure. 
     Typically such slicing machines include a rotating blade and a product feeder that drives the product forward towards the blade so that successive slices are cut from one face of the product. The distance through which the product is advanced between successive cuts of the blade determines the thickness of the slices. Where the product is of uniform shape and density, it may be sufficient to use a single predetermined slice thickness to give a slice or group of slices of the required weight. Further, it may be sufficient to provide an output scale proximate the output side of the blade to measure the current weight of the slice to product and adjust the thickness of the subsequent slice(s) to make the desired unit weight. 
     In general, however, variations in the shape and density of the product mean that the weight of a slice of a given thickness varies. A previous approach to dealing with this variation is described in U.S. Pat. No. 4,428,263, which is hereby incorporated by reference. That patent describes a process in which an automatic slicing machine is programmed to vary the thickness of the slices in accordance with a typical weight distribution for the product. 
     It has also been proposed to make some determination of the cross-sectional area of the product as it is cut. One such system is purportedly disclosed in U.S. Pat. No. 5,136,906, titled “Slicing Machine”, and assigned to Thurne Engineering Co., Ltd. According to that patent, a slicing machine for cutting slices from a product includes a camera arranged to view a cut face of the product, boundary recognition apparatus arranged to process image signals from the camera to determine a boundary of the cut face, calculating apparatus arranged to calculate a parameter characteristic of the cut face from image data corresponding to regions of the cut face within the boundary, and control signal generating apparatus arranged to generate a control signal to control the operation of the slicer in accordance with the determined parameter. 
     Although the foregoing system may be suitable for low-throughput slicing machines, it is significantly less suitable for high-speed slicing machines, such as those available from Formax, Inc., of Mokena, Ill., under the brand names FX-180® or PowerMax4000™. First, by calculating the product profile at the cut face, a very limited amount of processing time is available to perform the calculations that are necessary to ensure the proper thickness of each slice before the cut face must again be imaged for processing the thickness of the next slice. Second, substantial measurement inaccuracies may result from shadowing effects resulting from the relative positions of the illumination source, cut face, and slicing machine components—a problem not addressed in the &#39;906 patent. Third, further measurement inaccuracies are introduced by the apparent assumption that the profiles at the bottom and a side of the product are linear. Finally, by attempting to measure the product profile at the cut face, substantial inaccuracies may be introduced due to the presence of scrap product. One of the goals of the apparatus described in the &#39;906 patent is to remove the inaccuracies introduced by the scrap product. However, by addressing this problem at the cut face, the apparatus of the &#39;906 must necessarily introduce a further level and higher degree of image processing. 
       FIG. 1  illustrates a prior art product processing system described more completely in U.S. Pat. No. 7,450,247, herein incorporated by reference. The system is shown generally at  10 , and performs a physical process on a product in which the physical process is dependent on accurate measurement of the profile of the raw product, such as a slab or carcass of meat. As shown, product processing system  10  is comprised of a product profiling apparatus  15  and a product processor  20 . The product profiling apparatus  15  functions to measure the profile of the raw product and provide the profile information to the product processor  20  that, in turn, uses the information to accurately execute the physical process that is to be performed on the raw product. 
     In the embodiment illustrated in  FIG. 1 , the acquisition of the product profile information is completed before the particular raw product undergoes physical processing in the product processor  20 . Using the configuration shown in  FIG. 1  in which the profiling apparatus  15  is disposed prior to the product processor  20 , it is possible to acquire complete product profiles for several individual raw products before each of the raw products is provided to the input of the product processor  20 . Additionally, if the profiling apparatus  15  is designed as a stand-alone apparatus, then the profiling apparatus  15  may be used to provide product profile information to a plurality of different product processors that are operating in either a time sequential or concurrent manner. 
     Generally stated, the profiling apparatus  15  is comprised of an input section  25 , a scanning section  30 , and an output section  35 . The input section  25  includes a conveying surface  40  disposed to support the product  45  that is to be profiled. 
     Scanning section  30  includes a housing  55  having an input end that is open to receive product  45  and an outlet end that is open to allow product  45  to exit therefrom. In the illustrated embodiment, housing  55  comprises a principal housing portion  60 , an upper vision system housing  65 , and a lower vision housing  70 . The upper vision system housing  65  includes an upper vision system disposed therein. The upper vision system of the disclosed embodiment includes a vertically directed line laser  75  for illuminating one side of the product in a fixed plane traversed by the driven product and an associated camera  80  vertically angled for imaging the laser-illuminated contour of the product  45 . Similarly, the lower vision system housing  70  includes a lower vision system disposed therein that is comprised of a line laser  85  and corresponding camera  90  for addressing the other side of the product. Each of the upper and lower vision system housings  65  and  70  includes an opening that is positioned to allow the respective vision system to view a product  45  passing through the principal housing  60 . These openings may merely comprise cut out sections. Preferably, however, the openings are covered with a transparent material to form a window that mechanically isolates the vision system components from the components disposed in the principal housing  60  yet does not interfere with the vision system operation. While the prior art system of  FIG. 1  is capable of obtaining a product profile, there exists a need for a product profiling system that obtains profile information with more precision. 
     The present inventors have addressed many of the foregoing problems inherent in the product profiling operations of prior art. To this end, they have developed an accurate and cost-effective product profiling apparatus that is suitable for use, for example, in connection with high-speed product slicing machines. 
     Numerous other advantages and features of the present invention will be become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings. 
     SUMMARY OF THE INVENTION 
     An apparatus for acquiring a profile of a product for use in subsequent processing of the product is set forth. The apparatus includes a scanning chamber for accepting the product and one or more product drives that are operable to drive the product through the scanning chamber prior to delivery of the product to a subsequent product processor. The apparatus also includes a vision system disposed to acquire visual information relating to the profile of the product prior to delivery of the product to a subsequent product processor and a control system connected for control of the vision system and operating to convert the information received from the vision system into a format suitable for use by a subsequent product processor. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a prior art product processing system. 
         FIG. 2  is a schematic block diagram of one embodiment of a control system that may be used in the profiling apparatus of the present invention. 
         FIG. 3  is a perspective view of a product processing system constructed in accordance with one embodiment of the present invention. 
         FIG. 4  is a perspective view of the product profiling apparatus with housings removed for clarity. 
         FIG. 5  is a perspective view of the product profiling apparatus with housings removed for clarity. 
         FIG. 6  is a perspective view of the processing line downstream of the profiling apparatus. 
         FIG. 7  is a side view of a product processing system constructed in accordance with one embodiment of the present invention. 
         FIG. 8  is a side view of the product profiling apparatus. 
         FIG. 9  is a cross sectional view of the scanning section. 
         FIG. 10  is a top view of the processing line downstream of the profiling apparatus. 
         FIG. 11  is a side view of the weigh scale. 
         FIG. 12  is a side view of the weigh scale. 
         FIG. 13  is a top view of the weigh scale. 
         FIG. 14  is a perspective view of the weight scale with the conveying surface removed for clarity. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     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. 
     The disclosed embodiments of the present invention are improvements to the prior art referenced in  FIG. 1  and the prior art disclosed in U.S. Pat. No. 7,450,247, herein incorporated by reference except where inconsistent with the present disclosure. Prior art, as shown in  FIG. 1 , uses a single laser line in each of the upper and lower vision system housings  65  and  70 . U.S. Pat. No. 7,450,247 discloses the use of two opposing line lasers for illuminating downwardly and across the product from opposed sides of the product in each of the upper and lower vision system housings  65  and  70 . 
     It is considered more preferable, as further discussed below, that the upper vision system housing  265  ( FIG. 3 ) contain two opposing line lasers for illuminating downwardly and across the product from opposed sides of the product, and a top line laser illuminating downwardly in a plane perpendicular to the plane generated by the two opposing line lasers; and a side vision housing  266 , illustrated in  FIG. 3 , containing a side line laser  902  ( FIG. 4 ) for illuminating a side of the product in a plane perpendicular to the plane generated by the top line laser. 
     The principal housing  261 , illustrated in  FIG. 3 , comprises upper housing  265 , side housing  266 , and lower housing  270 . Product (not shown) is moved along the production line by product drives providing a conveying surface  240  such as a conveyor belt. Conveying surfaces are preferably driven by drive belts (not shown) at a constant, precise velocity by, for example, a servo motor or a motor with a resolver. At the output section  235 , the product (not shown) is engaged by a staging belt  700  which conveys the product to a subsequent product processor  220 , such as a slicing machine. The slicing machine can be a high speed slicing machine such as a Formax FX-180® or PowerMax4000™ machine or as described in U.S. Published Application US2009/0151527, herein incorporated by reference. 
       FIG. 2  is a schematic block diagram of one embodiment of a control system suitable for controlled operation of product profiling apparatus of the present invention. In the illustrated embodiment, the control system comprises a controller  150  that can be responsible for some or all of the functions 1) controlling the drive mechanisms associated with various portions of the profiling apparatus  15 ; 2) coordinating the operation of the vision systems, including acquisition of the profile data; and 3) communicating the profile data to control systems for one or more product processors  20 . To this end, the controller  150  is connected to receive sensed signals from and provide motion control signals to each of the input and output section drives  155  and  160  and the scanning section drive  165 . Similarly, the central controller  150  is connected to receive sensed signals from and provide scanning control signals to the upper, lower and side vision systems  170 ,  175  and  172 . 
     Ultimately, the profile information acquired from the upper, lower, and side vision systems  170 ,  175  and  172  is communicated to the control system  180  of at least one product processor  220 . Profile information may be communicated to the control system  180  in any one of a variety of processing states. For example, the controller  150  may communicate raw profile data to the control system  180 . Alternatively, or in addition, the controller  150  may communicate the profile information after the raw data it acquires has been processed at the controller  150  thereby relieving the control system  180  from much of the additional processing overhead associated with profile calculations. The controller  150  can be located in whole or in part with the control system  180 . 
     If more than one product processor  220  is to be served by a single product profiling apparatus  215 , then a method for tracking each product  45  ( FIG. 1 ) through the system to insure that each of the product processors  220  receives the correct profile data should be provided. For example, each of the products  45  may be provided with a bar-code or other visual image marker that may be acquired or otherwise input to the central controller  150  as well as the particular control system  180 ,  180 ′,  180 ″ associated with the particular product processor  220  that is to slice the particular product. When the identity of the product  45  that is to be sliced by the product processor is determined by the respective control system  180 ,  180 ′,  180 ″, the particular control system may request the profile data associated with the identified product from the central controller  150 . 
     In operation, the profiling apparatus  215  is as illustrated in  FIGS. 3 and 7 . First, the product ( FIG. 3 ) is provided at input section  225  where it is supported by a conveying surface  240 . The controller  150  ( FIG. 2 ) then activates input section drive  155  to move the product into the scanning section  330  ( FIGS. 3 and 7 ). Top and bottom pairs of opposing line lasers  900  ( FIGS. 4 and 9 ) are mounted on a support frame  910 , which is enclosed in a housing (not shown). Pairs of opposing line lasers  900  are arranged angled towards each other, as illustrated in  FIGS. 4 and 9 , such that their beams  966  ( FIG. 9 ) overlap on at least a portion of the product  45 . The opposing line lasers provide for higher resolution camera imaging, as discussed in U.S. Pat. No. 7,450,247. A top line laser  901  is also mounted to the support frame  910 . The top line laser illuminates downward along the length of the product, generating a top laser line  920  ( FIG. 5 ) parallel to the direction of travel “A.” 
     Two angled cameras  940  ( FIGS. 5 and 9 ) are positioned on the top portion  911  of the support frame  910  on the side opposite line lasers  900 ,  901  ( FIGS. 4 and 9 ). The angled cameras  940  are arranged as illustrated in  FIGS. 5 and 9 , such that their image area  967  overlaps on a least a portion of the product  45 . A bottom camera  950  ( FIGS. 5 and 9 ) is attached to a bottom portion  912  of the support frame  910 . The bottom of the profiling apparatus comprises two opposing line lasers  900  mounted on the support frame  910 , and a camera  950  attached to the support frame  910  to capture images from the bottom. 
     In accordance with one embodiment of the profiling apparatus  215 , a resolver or the like associated with the scanning section drive  165  ( FIG. 2 ) generates control pulses corresponding to incremental movement of the product over a fixed distance through the principal housing  261  ( FIGS. 3 and 7 ). These control pulses are used as synchronization signals that the controller  150  uses to trigger the acquisition of a profile reading. Here, the profile readings are in the form of a visual image captured by the cameras  940 ,  950 , and optionally  960  ( FIGS. 5 and 9 ), at fixed increments along the length of the product  45 . The product profile is accentuated by directing a line of laser light from the line lasers  900  across the upper and lower surfaces of the product, and along the longitudinal length of the upper surface.  FIG. 5  illustrates the laser light across the width  920  and along the longitudinal length  930  of the upper surface of a food product  45 . Accordingly, the interior of the principal housing  261  is advantageously dark so that cameras  940 ,  950  and optionally  960  may detect the line projected by line lasers  900 ,  901 ,  902 . 
     The angled arrangement of the cameras  940  ( FIGS. 5 and 9 ) allows improved profile analysis of the product. The two angled cameras  940  each work in conjunction with the top laser to acquire images along the side surfaces of the product. Images captured on the angled cameras  940  are used to generate images from the top, left and right surfaces of the slab, with the dividing line between the left and right surfaces being the top laser line, which is often generally, but not necessarily, along the center of the product due to the often irregular shape of food products. Profile analysis using captured images from the two angled cameras  940  uses the top laser line  920  as a reference for generating information about the contour of the product. When a portion of the product is analyzed from each side, the top laser line  920  indicates a point where analysis from either side can be merged without overlapping the profiling information calculated for each side. Thus, an exact centerline need not necessarily be used. 
     An optional top camera  960  can be provided to gather additional images. However, the use of a top camera  960  is not required to operate the system  210 . Two angled cameras can be arranged on the bottom, in a similar fashion to the top angled cameras  940 . However, because the bottom portion of the product is generally more flat than the top surface, the bottom surface profile is usually adequately imaged using the arrangement show in  FIGS. 4, 5 and 9 . The bottom camera  950  is able to capture images generated by the pair of bottom opposing line lasers  900  because a small open junction  935  in the conveying surface, as a result of situating two conveying surfaces adjacent to each other ( FIGS. 4 and 8 ), allows for the opposing lines generated by the opposing line lasers, and the camera, to reach a portion of the bottom of product exposed between the junction  935 . 
     The profiling apparatus  215  in  FIGS. 4, 8 and 9  further comprise a side laser  902 . The side laser  902  is mounted to the support  910 , and assists in providing additional illumination to areas that may be shadowed as a result of product shape irregularities. A second side laser can be provided opposite of and positioned across the conveying surface from the side laser  902 , however, having only one side laser is often sufficient to provide illumination of the product, particularly in cases where one side of the product has a higher contour than another. 
     The product processing system  210 , as illustrated in  FIG. 3 , may include a weigh scale  230  ( FIGS. 11-14 ) for weighing the product. This weigh scale can be situated at the beginning of the processing line, in advance of the profiling apparatus, within the profiling apparatus, or after the profiling apparatus. The stand alone nature of the weigh scale  230  mounted on a pedestal  431  as seen in  FIG. 11 , allows the scale to be easily moved into various positions along the processing stream. The weigh scale  230  comprises a conveying surface  432 , such as a conveyer belt, which is driven by a drum motor  433  on one end, and an idle roller  434  on the opposite end. The conveying surface is supported by support frames  461 , and inner support rods  460  ( FIGS. 13 and 14 ). Each end of the support frames  461  and inner support rods  460  are connected to a horizontal bar  440  ( FIGS. 12-14 ). Two load cells  450 , such as the BEAM LOAD CELL BBL sold by Eilerson Industrial Sensors, are disposed between the inner support rods  460 . The load cells  450  comprise an inner end  452  and an outer end  451 . The outer ends  451  of the load cell  450  are attached to a triangular plate  441 , which are connected to the horizontal bars  440 . The inner ends  452  of the load cell are attached to a diamond shaped frame  470  ( FIGS. 13 and 14 ) mounted to a central bar  471  of the pedestal  431 . Load cells  450  are connected to the triangular plate  441  and the diamond shaped frame  470  through the use of screws  481 ,  480  respectively. Horizontal bars  440  are connected to the triangular plate  441  through the use of screws  482 . 
     The output of the scale may be signal connected to controller  150  or the control system  180 . Controller  150  may be programmed to calculate the overall volume of a product based on the profile measurements. Controller  150  may then use the overall product value and the weight provided by the digital scale to calculate the average density of a product. The average density measurement may be used by the product processor  220 , which can be a slicing machine, in combination with the profile measurements to calculate the product slice thicknesses that are required to make a particular weight, such as the weight of product slices that are to be provided in a single consumer package. Alternatively, one or more of the average density, overall volume, or product profile measurements/calculations may be executed by the control system  180  of the slicing machine. The slicing machine can be, for example, the slicing machine disclosed in U.S. Published Patent Application US2009/0151527. 
     Once a product profile has been analyzed, the product is moved to a staging belt  700  ( FIGS. 3, 6 and 10 ) which transfers the product to staging positions  730 A,  730 B ( FIG. 6 ). Product is transferred by the staging belt  700  to either of two staging positions  730 A,  730 B through lateral movement of the staging belt  700  along support rods  720  ( FIGS. 6 and 10 ). The staging positions  730 A,  730 B correspond to product lift trays of the slicing apparatus which, once loaded with product, tilt up and load the products onto the slicing plane. Details of this lift tray can be found in U.S. Published Patent Application US2009/0151527. 
     The lateral movement of the staging belt  700  can be driven by a linear actuator such as a servo motor screw drive  710  as illustrated in  FIGS. 3 and 10 . The controller  150  or the control system  180  or both can communicate sufficiently such that the surface profile and/or the volume and/or the density of the product loaded into position  730 A is known by the product processor  220  and is tracked all the way to the slicing operation. The controller  150  or the control system  180  or both can communicate sufficiently such that the surface profile and/or the volume and/ or the density of the product loaded into position  730 B is known by the product processor  220  and is tracked all the way to the slicing operation. 
     From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred. 
     All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein, except where inconsistent with the present disclosure.