Abstract:
A food packaging system including a film dispensing device and a perforation device configured to create perforations in a film dispensed by the film dispensing device. The system also includes a wrapping device configured to wrap a food product in the film, and a controller configured to control the perforation device to produce a predetermined perforation pattern in the film. The film extends continuously while moving from the dispensing device to the wrapping device. The perforation device is positioned so that the film is perforated after leaving the dispenser and prior to the food product being wrapped in film.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims priority to and the benefit of U.S. Provisional Patent Application No. 61/870,900, filed Aug. 28, 2013. The foregoing provisional application is incorporated by reference herein in its entirety. 
     
    
     BACKGROUND 
       [0002]    The present application relates generally to the field of food product packaging. More specifically, the present application relates to a packaging system including a perforation system that forms a multitude of small openings or perforations in a plastic film for use in the packaging of a food product in a wrapping system. 
         [0003]    Instead of being processed and packaged by a butcher at a retail location, carcasses are commonly cut at a meat packing location and shipped to the retail location as what is commonly known as case-ready (e.g., store-ready, shelf-ready, etc.) meat. Case-ready meat is shipped in vacuum packages or modified atmosphere packages (e.g., an atmosphere with a specific concentration of gasses such as nitrogen, carbon dioxide, carbon-monoxide, etc.) (MAP) to delay spoilage of the meat such that it can be shipped and have a desired shelf life at the retail location. The portions of meat are generally first individually wrapped in a film and then several wrapped cuts of meat are packaged in an outer vacuum packages or MAP. At the retail location, the outer packaging may be opened and the individually wrapped cuts of meat may then be placed on the shelf for purchase. The lack of oxygen in vacuum packages and some MAP can cause the meat to appear in its “true” color (e.g., dark reddish purple for beef and dark pink for pork). While this does not mean the meat is spoiled, consumers may be less likely to purchase the meat because it is not a more desirable color (e.g., bright red for beef and bright pink for pork), which is often associated with freshness. The film in which the individual portions of meat are wrapped may be perforated and oxygen permeable such that the meat can be exposed to oxygen once the outer packaging is opened and turn to a more desirable color when on the shelf 
         [0004]    Traditionally, a perforated film is provided on a roll at the meat packing location and used to individually wrap the meat. The perforations can make the film more susceptible to damage during the process as it is fed from the roll, resulting in an incorrectly packaged portion of meat or a disruption in the packaging process from having to stop a machine, remove a damaged portion of film, and reset the machine. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    Features, aspects, and advantages of the present invention will become apparent from the following description and the accompanying exemplary embodiments shown in the drawings, which are briefly described below. 
           [0006]      FIG. 1  is a schematic view of a food product wrapping system, according to an exemplary embodiment. 
           [0007]      FIG. 2  is a schematic perspective view of a perforation device for the food wrapping system of  FIG. 1 , according to an exemplary embodiment. 
           [0008]      FIG. 3  is a block diagram of a control system for the perforation device of  FIG. 2 , according to an exemplary embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0009]    It is to be understood that the following detailed description are exemplary and explanatory only, and are not restrictive of the invention. 
         [0010]    The packaging system described herein provides a novel system for wrapping a food product in a perforated film. The packaging system is connected to the wrapping system such that an un-perforated film is fed from a roll, perforated, and then provided to the wrapping system with a minimal amount of handling between the perforation system and the wrapping system. 
         [0011]    It should be noted that the term “exemplary” as used herein to describe various embodiments is intended to indicate that such embodiments are possible examples, representations, and/or illustrations of possible embodiments (and such term is not intended to connote that such embodiments are necessarily extraordinary or superlative examples). 
         [0012]    References herein to the positions of elements (e.g., “top,” “bottom,” “above,” “below,” etc.) are merely used to describe the orientation of various elements in the FIGURES. It should be noted that the orientation of various elements may differ according to other exemplary embodiments, and that such variations are intended to be encompassed by the present disclosure. 
         [0013]    Referring to  FIG. 1 , a packaging system  10  is shown according to an exemplary embodiment. The packaging system  10  includes a wrapping system  12  configured to wrap a food product  16  in a film  14 . According to an exemplary embodiment, the film  14  is a polymer film (e.g., polypropylene film). For example, the wrapping system  12  may fold or wrap the film  14  around the food product and seal the layers of the film  14  together around the food product  16  to form a packaged food product  18 . The film  14  may be pre-printed with indicia or information (e.g., labels, graphics, nutritional information, price tags, cooking instructions, etc.). The film  14  includes a multitude of openings, shown as perforations  15  to allow the film  14  to be semi-permeable to a gas such as oxygen. In one embodiment, the perforations  15  may be generally circular holes. In other embodiments, the perforations  15  may be another shape, (e.g., a slot, slit, etc.) 
         [0014]    The packaged food product  18  may be subject to further processing after being wrapped in the wrapping device or system  12 , such as being placed on a tray and/or wrapped or placed in an outer packaging. The outer packaging, for example, may be a vacuum package, or a MAP to provide case-ready packaging for the food product. 
         [0015]    According to an exemplary embodiment, the food product  16  is a meat product (e.g., a portion of ground meat, whole muscle meat, etc.). In another embodiment, the food product packaging system  10  may be configured to package a food product formed completely or partially of vegetable material, soy, bread, or another food product that may benefit from being packaged in a perforated film. 
         [0016]    The film  14  is provided in an un-perforated form (e.g., on a roll or other storage and dispensing device) and fed to the wrapping system  12 . As shown in  FIG. 1 , the film  14  may extend continuously from the dispensing device (e.g., roll) to the wrapping device  12 . The perforations  15  are formed in the film  14  by a perforation device or system  20  that is provided in close proximity to the wrapping system  12  such that there is minimal routing and handling of the perforated film  14  between the perforation system  20  and the wrapping system  12 , reducing the likelihood of tears or ruptures in the film  14 . In some embodiments, the perforation system  20  may be integrated into the wrapping system  12 . A control system (i.e., control device or controller)  22  coordinates the operation of the perforation system  20  with the feed of the film  14  such that the perforations  15  are formed in the film  14  at a desired spacing or concentration. 
         [0017]    Referring to  FIG. 2 , the perforation system  20  and the control system  22  are shown according to an exemplary embodiment. The perforation system  20  includes a laser emitter  24  configured to project a laser beam  25  at the film  14  to create the perforation  15  in the film  14 . According to an exemplary embodiment, the laser emitter  24  is a CO 2  laser generating an infrared beam  25  that is approximately ¼″ in diameter and a power output that is capable of burning through the material of the film  14 . In one embodiment, the laser emitter  24  is positioned to the side of the film  14  and projects the laser beam  25  in horizontal direction, directed at a laser head  26  positioned above the film  14 . In other embodiments, the laser emitter  24  may be positioned elsewhere, such as above the laser head  26  or integrated into the laser head  26 . The beam  25  is directed (e.g., reflected) downward by a mirror  28  towards the film  14  and focused at the film  14  by a converging lens  30  to burn the perforation  15  in the film  14 . The laser head  26  is movable in a lateral direction along an x-axis  60  to create a line of perforations  15  at various locations along the width of the film  14 . 
         [0018]    The focal length of the converging lens  30  may be adjusted to create a perforation of a desired diameter. The diameter of the perforations  15  are further controlled by controlling the duration of the laser pulse and the power of the laser beam  25 . According to an exemplary embodiment, the perforations  15  have a diameter between 5 microns and 250 microns (0.0002 in. and 0.01 in.). According to a preferred embodiment, the perforations  15  have a diameter of approximately 75 microns (0.003 in.). 
         [0019]    A support plate  32  is positioned below the film  14  and the laser head  26  such that the film  14  is tensioned over the upper surface of the support plate  32  in the proximity of the laser head  26 . The support plate  32  flattens the film  14  in and helps to maintain a controllable and consistent distance between the film  14  and the laser head  26 . The distance between the support plate  32  and the laser head  26  may be varied by adjusting the position of the laser head  26  and/or the support plate  32  (e.g., along a z-axis  62 ) to vary the diameter of the perforation  15  formed in the film  14  by the beam  25 . The support plate  32  includes an opening  34  aligned with the laser head  26  and positioned below the location at which the laser head  26  focuses the beam  25  such that the beam  25  can pass through the opening  34  after penetrating the film  14 . According to an exemplary embodiment, the opening  34  is a slot with a width that is greater than the diameter of the largest potential perforation. In other embodiments, the opening  34  may be otherwise shaped. For example, the opening  34  may include a multitude of separate holes aligned with potential locations at which perforations  15  may be formed in the film  14 . 
         [0020]    One or more sensors  36  may be positioned beneath the support plate  32 . The sensor  36  detects the presence of the laser beam  25  to detect if the laser beam  25  has burned through the film  14  and has created the perforation  15 . The sensor  36  may be, for example, a heat sensor. In one embodiment, a single sensor  36  is positioned beneath the support plate  32  and is aligned with one of the positions at which a perforation  15  may be formed in the film  14  to spot check the operation of the perforation system  20 . In another embodiment, multiple sensors may be positioned beneath the support plate  32  and aligned with multiple positions at which a perforation  15  may be formed in the film  14  to perform a more comprehensive check of the operation of the perforation system  20 . In yet another embodiment, a single sensor may extend along the entire width of the support plate  32  such that it is capable of detecting the penetration of the laser beam  25  at any point along the width of the film  14 . In yet another embodiment, the sensor  36  may be coupled to the laser head  26  and may move relative to the film  14  and the support plate  32  with the laser head  26 . 
         [0021]    A ventilation system  38  (e.g., exhaust system, suction system, vacuum system, etc.) may be provided proximate the perforation system  20  (see  FIG. 1 ). The ventilation system  38  is configured to collect any vapors or other byproducts created when the laser beam  25  burns through the film  14  and remove them from the area of the perforation system  20 . The ventilation system  38  may, for example, include a vent hood positioned above the perforation system  20 . 
         [0022]    The laser head  26  is moveable to form perforations  15  at various positions along the width of the film  14 . According to an exemplary embodiment, the laser head  26  is moveable along the x-axis  60  with a shuttle mechanism  40 . The laser head  26  is coupled to a shuttle or slide  42  that moves along rails  44 . The slide  42  is fixed to a timing belt  46  that extends around pulleys  48  positioned on either side of the shuttle mechanism  40 . At least one of the pulleys  48  is rotated by a motor  50  to move the timing belt  46 . The laser head  26  is therefore moved through the interconnection of the timing belt  46 , the slide  42 , and the laser head  26 , to vary the position along the x-axis  60  of the perforation  15  formed in the film  14 . 
         [0023]    To form a row of perforations  15 , the laser head  26  is moved to a desired position and the laser emitter  24  is activated. The beam  25  is directed towards the film  14  and burns through the film  14  to form the first perforation  15 . The laser emitter  24  is then deactivated and the motor  50  is rotated to advance the laser head  26  to a new position. The process is repeated until a desired number of perforations  15  have been made in the row. The perforations  15  may be formed over only a portion of the width of the film  14 . The perforations  15  may be formed over the entire width of the film  14  or may be formed over only a portion of the film  14 . For example, the film  14  may have a width of approximately 18 in. while the perforations  15  are only formed in a portion having a width of approximately 6 in (e.g., in a strip down the center of the film  14 ). The perforations  15  need not be regularly spaced. In other embodiments, the perforations  15  may have varied spacing (e.g., a higher concentration of perforations  15  in the center of the film  14  than towards the edges of the film  14 ) or may be randomly located. The perforations may be randomly distributed throughout the film. 
         [0024]    Subsequent rows of perforations  15  are formed as the film  14  is advanced relative to the perforation system  20  (e.g., along a y-axis  64 ). The film  14  may be advanced continuously. To reduce the cycle time, a first row of perforations  15  may be is formed with the laser head  26  moving in a first direction, while the next row of perforations  15  is formed with the laser head  26  moving back in the opposite direction. In one embodiment, the feed rate of the film  14  (e.g., the rate at which the film  14  moves along the y-axis  64 ) is detected with an encoder  52 , shown in  FIG. 2  as being positioned on the top surface of the film  14 . The encoder  52  rotates as the film  14  advances and converts the angular motion into a digital signal that is utilized by the control system  22  to determine the feed rate of the film  14 . The data provided by the encoder  52  may then be used by the control system  22  to time the movement of the laser head  26  along the x-axis  60  by the shuttle mechanism  40  (e.g., the traverse speed, interval at each perforation, time between cycles, etc.). 
         [0025]    Other systems and methods may be used to coordinate the timing of the movement of the laser head  26  along the x-axis  60  with the feed rate of the film  14 . In another embodiment, the feed mechanism for the film  14  may provide a pulse to the control system  22  at an interval related to the feed rate of the film  14 . In yet another embodiment, the laser head  26  cycle time may be input directly by the operator, who may specify a desired cycle time using the control system  22 . In yet another embodiment, the film  14  may include marks printed at regular intervals and the perforation system  20  may include a sensor (e.g., a registration sensor) that detects the marks, with the time between marks being used by the control system  22  to determine the speed of the film  14  and the timing of the shuttle mechanism  40 . 
         [0026]    Alternatively, the laser head  26  may be directed to form perforations  15  at different points by rotating instead of moving along the x-axis  60  with the shuttle mechanism  40 . As shown in  FIG. 2 , the perforation system  20  may include a pivot motor  54 . The pivot motor  54  rotates the laser head  26  about a rotational axis parallel to the y-axis  64 . As the laser head  26  is rotated, it directs the laser beam  25  at an angle instead of vertically to a position directly below the laser head  26 . The laser beam  25  may therefore be directed to any point along the width of the film  14  to create a perforation  15 . According to an exemplary embodiment, the reflecting mirror  28  is positioned such that the rotational axis  66  passes through the reflecting mirror  28 . The reflecting mirror  28  therefore remains in the path of the horizontal laser beam  25  as the pivot motor  54  rotates the laser head  26 . The rotation of the laser head  26  with the pivot motor  54  may be timed by the control system  22  and coordinated with the feed rate of the film  14  to achieve a desired number and spacing of perforations  15  in each row and a desired spacing between rows. 
         [0027]    In some embodiments, as shown in  FIG. 3 , the perforation system  20  may include both the shuttle mechanism  40  and the pivot motor  54  such that the laser head  26  may be both moved along the x-axis  60  and may be rotated about the rotational axis  66 . The pivot motor  54  may be fixed to the slide  42  and coupled to the laser head  26  with a shaft. The pivot motor  54  may be positioned on the opposite side of the slide  42  from the laser head  26  and the shaft may extend through an opening in the slide  42 . 
         [0028]    Referring to  FIG. 3 , a schematic block diagram of the control system  22  and the perforation system  20  are shown according to an exemplary embodiment. The control system  22  is configured to manage the operation of the perforation system  20  to achieve a desired pattern and/or concentration of perforations  15  in the film  14 . In an exemplary embodiment, the control system  22  includes a processor  70 , a memory device  72 , a user input device  74 , and an output device  75 . According to an exemplary embodiment, components of the control system  22  may be housed in an industrial cabinet to protect the components from the elements. 
         [0029]    The control system  22  is configured to determine the pattern of the perforations  15  by controlling the spacing of the perforations  15  in each row as well as the spacing between each row. The control system  22  may control the spacing of the perforations  15  through a variety of variables, such as the traverse speed of the laser head  26 , the time interval at each perforation  15 , the time interval between perforations, and the time interval between cycles. The control system  22  receives input from the encoder  52 , or from another sensor input device such as a film feed mechanism  76  or a registration sensor  78  configured to detect marks printed on the film  14  as described above. The control system  22  also receives input from the sensor  36 . The control system  22  sends outputs control signals to devices such as the laser emitter  24 , the motor  50  of the shuttle mechanism  40 , or the pivot motor  54 . The control system  22  may monitor other properties related to the perforation system  20  including the life of the laser head  26 , the supply of laser consumables, the operation of the ventilation system  38 , and the operation of the wrapping system  12 . 
         [0030]    The processor  70  can be implemented as a general purpose processor, an application specific integrated circuit (ASIC), one or more field programmable gate arrays (FPGAs), a group of processing components, or other suitable electronic processing components. In another exemplary embodiment, the control system  22  may include a controller lacking a processor or memory. For example, the control system may be a linear circuit. 
         [0031]    The memory device  72  (e.g., memory, memory unit, storage device, etc.) is one or more devices (e.g., RAM, ROM, Flash memory, hard disk storage, etc.) for storing data and/or computer code for completing or facilitating the various processes, layers and modules described in the present application. The memory device  72  may be or include volatile memory or non-volatile memory. The memory device  72  may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described in the present application. According to an exemplary embodiment, the memory device  72  is communicably connected to the processor via the processing circuit and includes computer code for executing (e.g., by processing circuit and/or processor) one or more processes described herein. 
         [0032]    The input device  74  is one or more devices that allow a user to input commands and control variables for the perforation system  20 . The input device  74  may be, for example, a touch screen monitor, a keyboard or keypad, push buttons, dials, switches, or any combination of devices. The output device  75  is one or more devices that allow a user to monitor the properties of the perforation system  20  and may be integrated with the input device  74 . The output device  74  may be, for example, a monitor, a touch screen monitor, a text display, a numeric display, or a combination of devices. 
         [0033]    The present disclosure contemplates methods, systems and program products on any machine-readable media for accomplishing various operations. The embodiments of the present disclosure may be implemented using existing computer processors, or by a special purpose computer processor for an appropriate system, incorporated for this or another purpose, or by a hardwired system. Embodiments within the scope of the present disclosure include program products comprising machine-readable media for carrying or having machine-executable instructions or data structures stored thereon. Such machine-readable media can be any available media that can be accessed by a general purpose or special purpose computer or other machine with a processor. By way of example, such machine-readable media can comprise RAM, ROM, EPROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store desired program code in the form of machine-executable instructions or data structures and which can be accessed by a general purpose or special purpose computer or other machine with a processor. When information is transferred or provided over a network or another communications connection (either hardwired, wireless, or a combination of hardwired or wireless) to a machine, the machine properly views the connection as a machine-readable medium. Thus, any such connection is properly termed a machine-readable medium. Combinations of the above are also included within the scope of machine-readable media. Machine-executable instructions include, for example, instructions and data which cause a general purpose computer, special purpose computer, or special purpose processing machines to perform a certain function or group of functions. 
         [0034]    It is important to note that the construction and arrangement of the system and method for overwrapping foods products using laser perforated film as shown in the various exemplary embodiments are illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter described herein. For example, elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may also be made in the design, operating conditions and arrangement of the various exemplary embodiments without departing from the scope of the present invention.