Patent Abstract:
A method for laser marking eggs is disclosed which comprises using a machine vision system to monitor laser marking of eggs by a laser marking system, and adjusting one or more parameters of the laser marking system based upon determinations made by the machine vision system. Additionally, a system for laser marking eggs is disclosed which comprise a machine vision system and one or more control elements. The machine vision system is configured and arranged to monitor laser marking of eggs by a laser marking system, and the one or more control elements are configured and arranged to adjust one or more parameters of the laser marking system based upon determinations made by the machine vision system. Further, a system for laser marking eggs is disclosed comprising multiple laser marking apparatuses and a central server. The laser marking apparatuses are configured and arranged to perform laser marking jobs queued by local computers for laser marking eggs being packed by egg packing stations. The central server is configured to distribute the laser marking jobs to the local computers. In addition, a method is disclosed for controlling laser marking jobs which comprises distributing the laser marking jobs from a central computer to local computers responsible for queuing laser marking jobs to one or more laser marking apparatuses configured and arranged to laser mark information on eggs.

Full Description:
RELATED APPLICATIONS 
       [0001]    This application is related to U.S. application Ser. Nos. ______, bearing attorney docket numbers N0481.70005U500, N0481.70006U500, N0481.70007U500, N0481.70008U500, N0481.70009U500, and N0481.70010US00, filed on even date herewith. The entire content of each of the foregoing applications is incorporated herein by reference. 
     
    
     FIELD 
       [0002]    The inventions described herein relate generally to the field of food product processing. Some described embodiments relate particularly to systems and techniques for laser marking or otherwise processing eggs. 
       BACKGROUND 
       [0003]    Eggs typically undergo a great deal of processing before they are ready to be sold to the consuming public. In many circumstances, for example, eggs pass through several processing stations at which they are washed, candled, weighed, graded, and packed into packages (e.g., cartons, crates, or other commercially distributed containers). Examples of such processing stations and mechanisms for conveying eggs from station to station are described, for instance, in the following U.S. patents assigned to Diamond Automations, Inc.: U.S. Pat. Nos. 4,189,898; 4,195,736; 4,505,373; 4,519,494; 4,519,505; 4,569,444; 4,750,316; 5,321,491; and 6,056,341, the entire contents of each of which are incorporated herein by reference. It is not uncommon for a facility in which these stations operate to output about one million eggs in a single day. Accordingly, to be commercially acceptable, the throughput of the stations needs to be quite high, with some stations typically processing on the order of 20,000 eggs per hour. 
         [0004]    Because eggs are a perishable item susceptible to spoilage, egg packages typically (and often by law or regulation) have expiration dates marked on them. Many consumers, however, move eggs from their packages into special receptacles in their refrigerators. When this is done, the consumer is no longer able to evaluate the expiration date of individual eggs prior to using them. 
         [0005]    Furthermore, certain governmental bodies, e.g., the United States Food and Drug Administration (FDA), the United States Department of Agriculture (USDA), and various state governments, currently do not allow retailers to “repack” eggs, i.e., to move eggs from one package to another. This restriction can result in tremendous waste because whenever the integrity of even a single egg in a package in the hands of a retailer is compromised (e.g., is broken), the entire package of eggs must be discarded. 
         [0006]    Several techniques for marking individual eggs with expiration dates and the like have been proposed. One such approach is to use vegetable dyes or other water-soluble ink products to mark eggs. Such products, however, have a tendency to leak into the interior of eggs and can result in undesirable ink spots within them. The tendency of such products to wash off or fade also means that such marking are susceptible to tampering and even unintentional loss of integrity (e.g., dripping and smearing from condensation and handling), and has generally limited their acceptance. 
         [0007]    It is also known to use lasers to mark indicia onto perishable products for the purpose of tracking their pedigree and/or integrity (e.g., using date codes and/or traceability codes), as well as for allowing textual or graphical advertising messages to be disseminated via such products. An example of a system for laser marking such information on hen eggs is described, for example, in U.S. Patent Application Publication No. 2008/0223834 (“the &#39;834 Application”), published on Sep. 18, 2008. The disclosure of the &#39;834 Application is incorporated herein by reference in its entirety. 
         [0008]    The approach described in the &#39;834 Application is to laser mark information on eggs as they are conveyed at high speed during the grading process. Although this approach has proven effective for certain applications, the extremely high throughput of the grading machines, the lack of uniformity in the moisture content of the surface of individual eggs during the grading process, and the significant amount of dust created during the laser marking process, among other things, have made it challenging to mark individual eggs with sufficient accuracy, reliably and consistency for certain purposes. 
       SUMMARY 
       [0009]    A method for laser marking eggs is disclosed which comprises using a machine vision system to monitor laser marking of eggs by a laser marking system, and adjusting one or more parameters of the laser marking system based upon determinations made by the machine vision system. 
         [0010]    Additionally, a system for laser marking eggs is disclosed which comprise a machine vision system and one or more control elements. The machine vision system is configured and arranged to monitor laser marking of eggs by a laser marking system, and the one or more control elements are configured and arranged to adjust one or more parameters of the laser marking system based upon determinations made by the machine vision system. 
         [0011]    Further, a system for laser marking eggs is disclosed comprising multiple laser marking apparatuses and a central server. The laser marking apparatuses are configured and arranged to perform laser marking jobs queued by local computers for laser marking eggs being packed by egg packing stations. The central server is configured to distribute the laser marking jobs to the local computers. 
         [0012]    In addition, a method is disclosed for controlling laser marking jobs which comprises distributing the laser marking jobs from a central computer to local computers responsible for queuing laser marking jobs to one or more laser marking apparatuses configured and arranged to laser mark information on eggs. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a side-view of an illustrative example of a laser marking apparatus embodying various features of the invention, configured to be operational with a conventional egg packing apparatus; 
           [0014]      FIGS. 2-4  are partially cut-away, perspective views of various components of the system shown in  FIG. 1 ; 
           [0015]      FIGS. 5A and 5B  are partial block diagrams of top and side views, respectively, of a portion of the conveyor used by the system shown in  FIGS. 1-4  and various components that may operate in conjunction therewith; 
           [0016]      FIG. 6  is a perspective view of an illustrative embodiment of an egg orienter that may be used in a system such as that illustrated in  FIG. 5 ; 
           [0017]      FIGS. 7A and 7B  illustrate side and front views, respectively, of an egg package containing eggs as it may appear after it has been processed by an egg orienter such as that shown in  FIGS. 5 and 6 ; 
           [0018]      FIG. 8  is an illustration of a front view of an egg as it may appear when marked using one or more the techniques described herein; 
           [0019]      FIG. 9  is a block diagram showing components of a computer network that may be employed to allow for centralized control of laser marking apparatuses located at different facilities; and 
           [0020]      FIGS. 10A and 10B  show perspective views of the two sides of a driving mechanism that may be used to move the egg orienter of  FIG. 6  in a desired manner. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0021]    We have recognized that laser marking eggs “on the fly” at high speeds, e.g., while the eggs are in motion through a grading station at speeds of typically about 100 to 300 feet per minute (fpm), can produce a less-than-ideal result in some circumstances in terms of marking quality and reliability. “Reliability,” in this context, refers to the percentage of eggs processed by the system that have clear, legible, and consistent markings on them (whether evaluated objectively or subjectively). For example, we have recognized that in order for a means of marking eggs with indicia suitable for repacking purposes to be both widely commercially viable and economically feasible, it is important for a large percentage of the eggs processed to have clear, legible, consistent markings. One reason for this is that, in many circumstances, eggs that are mismarked with such indicia must be discarded for one reason or another. 
         [0022]    In addition, we have observed, for example, that the limited window of time and finite space available for accessing and laser marking an egg using on-the-fly techniques typically permits only a limited amount of information to be laser marked on the egg in a direction extending along the egg&#39;s long axis. The inherent lack of accuracy in tracking a high-speed moving target, as well as the orientation, inevitable vibrations, and other motion within such a moving mechanical system, can further compromise the quality of the resulting image and render it insufficient for certain purposes. Moreover, our experience has shown that attempting to laser mark eggs during the grading process can be problematic for some applications because a typical process involves washing the eggs shortly before attempting to laser mark indicia onto them. The resulting lack of uniformity in the dryness of the surface of the eggs can result in inaccurate or uneven markings. Laser marking complex information, e.g., an intricate company logo, during the grading process can be particularly problematic for the foregoing reasons. 
         [0023]    In addition, the dust generated during the laser marking process can cause problems for both local (i.e., at the laser marking station) and downstream components. While vacuuming away excess dust can be performed, it has proven difficult in practice to accomplish effectively. 
         [0024]    Furthermore, when eggs are marked at a particular location, e.g., on their sides, before they reach the packer, there is a risk that the packer will put the eggs into the package in an orientation that precludes or obscures visibility. Accordingly, eggs marked by components upstream of the packer frequently are packed in such a way that the marked indicia on the egg will be hidden unless and until the egg is repositioned so as to be properly oriented for clear visibility of the marking. 
         [0025]    Additionally, when eggs are marked before they reach a packer, the ability to redirect the eggs to a needed location after they have been marked is restricted. That is, once eggs have been marked in particular way, they can be directed only to packers that are processing eggs consistent with the markings that were marked on them. For example, once an egg has been marked with a manufacturer&#39;s logo, that egg cannot thereafter be directed to a packer responsible for packing eggs for a different manufacturer. 
         [0026]    Significantly, we have found that integrating a laser marking process into an egg packing apparatus, rather than an upstream component such as a grading station, involves a different set of constraints and can produce substantial benefits. In particular, we have determined that laser marking eggs in a packing apparatus, after they have been placed into packages, can alleviate at least some, and perhaps even all, of the various drawbacks of the grader-based laser marking process discussed above. Indeed, we have observed in practice that an embodiment of the system described herein can result in a large improvement in laser marking quality and reliability over a grader-based system. Moreover, it allows laser marking on much more of the eggs&#39; surfaces and can do so without slowing down egg processing. 
         [0027]    In some embodiments, a continuous conveyor that carries filled packages of eggs may slow or stop periodically as each new row of each new package of eggs is loaded. Advantageously, the eggs in a loaded package may be laser marked during one or more of the periods (after the loading period) during which the package is held stationary as the rows of eggs are loaded into another upstream package. One or more sensors (e.g., photo eyes) and/or conveyor motion monitors (e.g., a monitor that counts ticks of a conveyor belt) may be used to determine precisely when a loaded package of eggs has moved into position to be lased. The accuracy of the laser marking can therefore be increased considerably simply because the eggs remain stationary during the lasing operation. In other embodiments, the conveyor may carry packed packages of eggs at a somewhat continuous rate in front of the laser-aiming mirrors (aka “galvos”). In such embodiments, a combination of sensors and conveyor motion monitors may be used to accurately track the position of the respective eggs during the lasing process. 
         [0028]    In some embodiments, multiple galvos may be used to laser mark the eggs in each package that passes by a laser marking station. In addition, packages of eggs typically advance on a conveyor of a packer at but a small fraction of the rate at which individual eggs move through an upstream grader. As such, using the implementations described herein, a significantly longer window of time may be available for each galvo to laser mark each individual egg. This additional available marking time may allow the galvos to increase the marking quality (e.g., contrast) significantly. 
         [0029]    Another potential benefit to laser marking eggs in packages is that the eggs may be manipulated so as to be oriented in the packages in a particular (uniform) manner in advance of the lasing process. For example, in some embodiments, eggs in the packages on the conveyor of a packer may be manipulated so that all of the eggs are centered and tilted slightly backwards, uniformly. As such, a relatively large surface area of the egg will be immediately visible to a consumer (or an inspector, vendor, or other person) who opens the package. By so orienting the eggs in the package prior to the lasing process, the amount of “visible” surface area made available to the laser, for marking, may be increased. In addition, the information that is actually marked on the eggs (expiration dates, tracking codes, advertisements, etc.) will be readily communicated to the consumer (or an inspector, vendor, or any other person who might subsequently open the package) immediately upon opening the package. As an example, a consumer opening a carton of eggs may immediately be presented with neatly arranged, uniformly oriented rows of eggs, each having information such as a company&#39;s logo and/or an expiration date prominently displayed at the same location and directly facing the customer. 
         [0030]    In addition to the above, laser marking eggs after they have been placed in packages can further be advantageous because of the limited number of components located downstream of the laser marking station and the reduced likelihood that the dust created during the laser marking process will interfere with the operation of any mechanical or optical components. In some embodiments, for example, the only operation performed by the packer following the laser marking process described herein is the closing of the package. Any dust generated by the laser marking process that escapes the vacuuming process described below (if employed) is unlikely to have a significant adverse affect on the operation of the package closing station. 
         [0031]    Furthermore, laser marking eggs after they have been placed in packages minimizes the risk that the marked section of the egg will end up hidden from view by a consumer opening the package. That is, when an egg is marked prior to being put in a package, there is a good chance that the egg will be placed in the package by the packer in such a way that the image marked on the egg will be obscured or not visible at all unless the egg is rotated, flipped end-to-end, or otherwise reoriented. Laser marking eggs after they have been placed in packages can minimize the risk that an egg will be so oriented when a consumer (or anyone else) opens a given package. 
         [0032]    Additionally, laser marking eggs after they have reached a particular packer ensures that only the eggs being processed by that packer will be marked with the desired information. Accordingly, laser marking eggs after they have been placed in packages allows eggs to be directed to any of numerous packers, or perhaps redirected to a different packer, at any time, without a concern that a given packer will receive an egg with inappropriate or unintended markings. 
         [0033]    An example of a laser marking apparatus embodying various inventive features described herein is illustrated in  FIGS. 1-4 . In the example shown, a laser marking apparatus  100  is configured to be retrofit onto an existing egg packing apparatus  200 , for example, of a type manufactured by Diamond Automations, Inc. It should be appreciated, however, that one or more, or perhaps even all, of the components of the laser marking apparatus  100  may additionally or alternatively be integrated into an egg packing apparatus such as that shown at the time of its manufacture. Additionally, it should be appreciated that the egg packing apparatus shown is but one example of an apparatus with which aspects of the invention may be employed and that various features of the invention may additionally or alternatively be employed in connection with any of a number of different types of apparatuses. 
         [0034]    As shown in  FIGS. 2 and 3 , the egg packing apparatus  200  may comprise a set of two identical egg packers  200   a ,  200   b , each including a conveyor  202   a ,  202   b  (e.g., a belt conveyor, roller conveyor, chain conveyor, etc.). Each conveyor  202   a ,  202   b  moves empty packages  204  through a respective egg loading section  206   a ,  206   b  at which eggs are loaded into them from above, and then moves the filled packages to a respective package closing section  208   a ,  208   b  that is responsible for closing the lids of the packages  204 . As shown in  FIG. 1 , eggs may be supplied to the egg packers  200   a ,  200   b  via a grader  300 . Although only a cross-section of the grader  300  is shown, it should be appreciated that the grader  300  will typically be a fairly large piece of equipment, commonly on the order of 50 or 60 feet long in a direction perpendicular to the packer conveyors. 
         [0035]    In the embodiment shown, the laser marking apparatus  100  comprises a pair of identical laser marking systems, one to service each of the two portions  200   a ,  200   b  of the egg packer  200 . The frame  101  in the illustrated example may, for example, be used to support both portions of the laser marking apparatus  100 . Alternatively, separate frames could be used. Because the configuration and operation of the two laser marking systems are essentially the same, only one of the two systems will be described. It should be understood, however, that the following description applies equally to both portions of the laser marking apparatus  100 . In should also be appreciated that the existence of two side-by-side laser marking systems is not a requirement of the invention, and that different embodiments may employ fewer or greater numbers of such systems. 
         [0036]    In the illustrated embodiment, a main housing  102  of one of the laser marking systems (shown in  FIG. 1 ) contains a group of three laser sources  104   a ,  104   b ,  104   c . Each laser source  104  may, for example, comprise a carbon dioxide (CO 2 ) laser. As shown, two-to-one beam splitters  106   a ,  106   b ,  106   c  may be used to divide laser energy from the laser sources  104  into multiple beams and minors may be used to direct the resulting six laser beams through a channel of a lower housing  108  (shown in  FIG. 1 ) to a set of six two-dimensional laser-aiming mirrors (galvos)  110 . In other embodiments, rather than employing beam splitters, a separate laser source may be employed for each galvo  110 . Each galvo  110  may thus, for example, be responsible for lasing two eggs in a package of twelve, or three eggs in a package of eighteen, or more eggs in a larger package. 
         [0037]    Electronic control boards  111  contained within the lower housing  108  may include conventional circuitry (analog, digital, etc.) to control the operation of the laser sources  104  and the galvos  110 . One or more sensors (not shown in  FIGS. 1-4 ) may also detect the position of egg packages on the conveyor with respect to the galvos  110  and allow the control boards  111  to determine when a given package filled with eggs is in position for lasing. In other embodiments, one or more control boards  111  may additionally or alternatively be located elsewhere in the system for easier accessibility, to allow for better ventilation, etc. 
         [0038]      FIGS. 5A and 5B  are block diagrams showing, respectively, top and side views of a portion of the conveyor and related components that may be disposed between an egg loading section  206  and a package closing section  208  of one of the two portions of the egg packing apparatus  200  shown in  FIGS. 1-4 . In the illustrative example shown, the conveyor is controlled so as to move packages  204  sequentially to each of five primary locations A-E. At each such primary location, moreover, the conveyor causes the package  204  to move sequentially through a series of sub-locations equal to the number of rows of eggs  205  in the packages  204  being loaded. This occurs because the egg loading section  206  typically loads one row of six eggs  205  at a time, thus requiring the conveyor  202  to move the package slightly forward prior to loading each new row of eggs. A typical egg packer will process approximately  35  cases of eggs per hour, with each case including 30 dozen eggs. At this rate, the packages may, for example, spend approximately 5 seconds at each of the primary locations A-E before being moved by the conveyor  202  to the next such primary location. The packages may thus, for example, spend approximately 1-2 seconds at each of the sub-locations within each of locations A-E. 
         [0039]    In the example shown, the conveyor  202  first moves the package  204  to a primary location A within the egg loading section  206  of the egg packing apparatus  200 . As shown, when the package  204  stops at this section, a number of eggs  205  corresponding to the number of receptacles in the package  204  (e.g., twelve, eighteen, or more) are disposed into the package  204 . As noted above, the eggs may be loaded one row (e.g., six eggs) at a time, with the conveyor  202  advancing the package  204  slightly to allow for subsequent rows to be loaded. 
         [0040]    Next, the conveyor moves the package  204  to a location B where an operation is performed to orient the eggs to a desired position for laser marking as well as for display to a consumer who ultimately opens the package  204 , or perhaps to an inspector or an employee of a retailer or distributor who later examines the eggs for inspection and/or repacking purposes. As shown, the eggs  205  may be oriented in a somewhat haphazard manner within the package at the time they reach the location B. Once they reach the location B, however, an egg orienter  112  may be operated so as to reorient the eggs into the desired position. The egg orienter  112  may be any of numerous devices capable reorienting the eggs within the package, and the invention is not limited to any particular device or structure for performing such a function. One illustrative example of an egg orienter  112  suitable for this purpose is shown in  FIG. 6 . It should be appreciated that the egg orienter  112  may be located at any of numerous positions along the conveyor  202  and need not be located the particular location shown. In some embodiments, for example, the equipment at the positions B and C in  FIGS. 5A  and B may be combined so as to operate on cartons of eggs located at the same position. Additionally, in some embodiments, the egg orienter  112  may be positioned to the right of the galvos  110  shown in  FIGS. 5A and 5B  rather than to the left thereof. 
         [0041]    As illustrated by arrows  113  adjacent the egg orienter  112  in  FIGS. 5A and 5B , the egg orienter  112  may first be moved (e.g., using via a pneumatic piston or another suitable actuator or motor—not shown in  FIGS. 5A  and B) down behind the egg package  204  and then may be swept forward (in the direction of normal belt movement) across the rows of eggs  205  (typically two or three rows of six eggs each). 
         [0042]    As illustrated by arrows  115  in  FIG. 5A , as it is moved forward, the egg orienter  112  may also be shimmied (e.g., using a rotating pneumatic actuator or another suitable actuator or motor—not shown in  FIGS. 5A  and B) in a side-to-side fashion so as to help overcome the friction between the eggs  205  and the receptacles of the package  204 . Finally, the egg orienter  112  may be raised and then moved back to its starting position until another row of eggs is moved into location B for processing. In some embodiments, the egg orienter  112  may be swept across the entire package of eggs in a single pass. Alternatively, it may be swept across one row of eggs  205  at a time each time the package  204  is moved to a new sub-location within location B. 
         [0043]    As shown in  FIGS. 5A and 5B , one or more sensors (e.g., photo eyes  214   a - b ) may be used, either alone or together with a belt tick monitor or the like, to track the precise position of the egg package  204  with respect to the egg orienter  112 . 
         [0044]    An example of a driving mechanism  122  that may be used to move the egg orienter  112  in a desired manner (e.g., as indicated by the arrows  113 ,  115  in  FIGS. 5A  and B) is shown in  FIGS. 10A and 10B . The driving mechanism  122  may, for example, straddle the conveyor  202  at the location B (see  FIGS. 5A-B ) so that packages of eggs pass underneath the egg orienter  112  in a direction indicated by the arrow  124  in  FIGS. 10A-B . As shown, the driving mechanism  122  may comprise a frame  126  that supports several double-acting pneumatic cylinders  128 ,  130   a ,  130   b  as well as a rotating pneumatic actuator  136 . In the example shown, the pneumatic cylinder  128  and associated pistons  142  are responsible for moving the egg orienter  112  up and down (i.e., perpendicular to a plane of the conveyor  202 ) as indicated by the arrow  132  in  FIG. 10A . Similarly, in the embodiment shown, the pair of pneumatic cylinders  130   a  and  130   b  and associated pistons  144  are responsible for moving the orienter  112  forward and backward over an egg package  204  (i.e., parallel to the direction of conveyor motion (see arrow  124 )), as indicated by the arrow  134  in  FIG. 10B . Also, in the embodiment shown, the rotating pneumatic actuator  136  is responsible for causing the egg orienter  112  to shimmy slightly from side to side as the egg orienter  112  is swept over the package  204  of eggs  205 , as indicated by the arrow  138  in  FIG. 10A . 
         [0045]    As shown in  FIG. 10B , the pneumatic components of the driving mechanism  122  may be connected to a compressor unit  140  (or other source of compressed air) that may be controlled so as to regulate the air flow to such components and thereby appropriately control their operation. Of course, embodiments that employ other types of actuators or motors (e.g., electric or hydraulic actuators or motors) may employ different types of control units to regulate movement of the egg orienter  112  in the desired manner. 
         [0046]    As shown in  FIG. 6 , the egg orienter may comprise a frame  114  made of a suitable light-weight, sturdy material (e.g., aluminum) and a brush element  116  for sweeping across the tops of the eggs  205  in the package  204  to reorient them into the desired position. The brush element  116  may, for example, comprise a set of flexible but resilient fingers made of a suitable food-grade plastic, rubber, or other material. In the example shown, the brush element  116  is fastened to the frame  114  using a scallop-shaped aluminum member  118  to impart to the brush element  116  a corresponding scallop shape. Shaping the brush element  116  in this way allows nooks of the scallop shape to appropriately position the eggs  205  into the desired left-to-right position within the package  204 . 
         [0047]    In the embodiment shown, the egg orienter  112  further includes a set of tubes  120  disposed between nooks of the scallop shaped aluminum member  118  and the frame  114 . As shown, the tubes  120  may be arranged such that a pair of them straddles each egg  205  as the egg orienter  112  is swept across the tops of the eggs  205  in the package  204 . Advantageously, a high-velocity air source (not shown) may be connected to the tubes  120  such that air may be blown onto and around the eggs  205  as the egg orienter  112  sweeps over the eggs  205  to reposition them. Blowing air over and around the eggs in such a fashion can help dry the surface of the eggs  205  uniformly prior to laser marking them and may also help overcome the friction between the bottoms of the eggs  205  and the package receptacles by creating a slight cushion of air between them. 
         [0048]    In the illustrative embodiment shown, after the egg orienter  112  has repositioned the eggs  205  within the package  204 , the conveyor  202  moves the package  204  to a location C at which a laser marking operation may be performed.  FIGS. 7A and 7B  illustrate how a group of eggs  205  may be oriented within a package  204  when the package  204  reaches the location C (as well as when the eggs ultimately reach a store, an end consumer, or some other post-packing location).  FIG. 7A  is a side view and  FIG. 7B  is a front view of a package  204  in which the eggs have been so oriented. 
         [0049]    As shown, as a result of the processing by the egg orienter  112 , the eggs  205  may be arranged uniformly within the package  204 , with each egg  205  being tilted slightly toward the back  228  of the package  204  (see  FIG. 7A ) so that a large portion  230  of its surface area is exposed to the galvo  110  responsible for marking on it. In some embodiments, for example, the egg orienter  112  may manipulate the eggs  205  such that a long axis  232  of each egg is tilted at least slightly toward the back  228  of the package. For example, in certain embodiments, the egg orienter  112  may manipulate the eggs such that a long axis of each egg is offset from vertical (with “vertical” being defined as a line  233  normal to a plane coincident with a bottom portion  236  of the package (which, in  FIGS. 7A and 7B , is parallel to the surface of the conveyor  202 )) by an angle Θ that is a minimum of 3 degrees. In other embodiments, each of the eggs  205  in the each carton  204  may be offset from vertical by an angle Θ that is a minimum of 1 degree, or a minimum of 2 degrees, or a minimum of 4 degrees, or a minimum of 5 degrees, or a minimum of 6 degrees, or a minimum of 7 degrees, or a minimum of 8 degrees, or a minimum of 9 degrees, or a minimum of 10 degrees, or a minimum of 11 degrees, or a minimum of 12 degrees, or a minimum of 13 degrees, or a minimum of 14 degrees, or a minimum of 15 degrees, or a minimum of 16 degrees, or a minimum of 17 degrees, or a minimum of 18 degrees, or a minimum of 19 degrees, or a minimum of 20 degrees, or a minimum of 21 degrees, or a minimum of 22 degrees, or greater. In some embodiments, the egg orienter 112 can manipulate the eggs 205 so that such angle Θ for each egg is approximately 10 degrees, or some other suitable angle that maximizes the surface area that is made available to the laser marking apparatus for writing. 
         [0050]    As shown in  FIG. 7B , the egg orienter  112  may additionally orient the eggs  205  so that the long axes  232  of all of the eggs in each row of six eggs form approximate right angles with respect to a line intercepting the bottoms of the receptacles holding the eggs in such a row. In some implementations, the long axes  232  of all of the eggs in a given package may be oriented such that each such long axis  232  is no more than about 20 degrees (or, in some embodiments, no more than about 25 degrees, or no more than about 24 degrees, or no more than about 23 degrees, or no more than about 22 degrees, or no more than about 21 degrees, or no more than about 19 degrees, or no more than about 18 degrees, or no more than about 17 degrees, or no more than about 16 degrees, or no more than about 15 degrees, or no more than about 14 degrees, or no more than about 13 degrees, or no more than about 12 degrees, or no more than about 11 degrees, or no more than about 10 degrees, or no more than about 9 degrees, or no more than about 8 degrees, or no more than about 7 degrees, or no more than about 6 degrees, or no more than about 5 degrees, or no more than about 4 degrees, or no more than about 3 degrees, or no more than about 2 degrees, or no more than about 1 degree) offset from any other such long axis. 
         [0051]    When the eggs  205  are oriented within the package  204  in such a manner, the surface of the egg  205  that is immediately apparent to someone opening the package is neither an end nor the middle of the egg  205 , but rather a section of the egg somewhere between those two points.  FIG. 8  shows an example of an egg  205  having laser marking on it. As shown, a point  234  in the center of the marking (also shown in  FIGS. 7A and 7B ) may be located between an end  210  and the middle  212  (i.e., the area located mid-way between the egg&#39;s two ends) of the egg  205 . In some embodiments, the information marked on the egg may extend from the end  210  of the egg (or beyond) to the middle  212  of the egg (or beyond). As shown in  FIG. 8 , the information may be marked on the egg so as to extend horizontally with respect to the egg&#39;s long axis. In some embodiments, information may additionally or alternatively be marked so as to extend vertically generally in a direction of the egg&#39;s long axis. In some embodiments, the information laser marked on each egg may comprise one or more of a company&#39;s logo, an expiration date, grading information, and packing codes (e.g., a state code, a county code, a packer code and/or a Julian date). 
         [0052]    In some embodiments, eggs may be oriented in each package and information may be marked on the eggs in such a way that the information marked on all of the eggs in each package can be viewed immediately upon opening the package, without requiring a human being to manipulate any of the eggs to allow such information to be viewed. It is known that a significant percentage the eggs that are produced have the salmonella virus on them. For this and other reasons, various regulations exist governing when and how eggs may be manipulated. Allowing inspection of laser marked information on all of the eggs in a given package without needing to manipulate any of the eggs in the package can thus provide significant advantages. 
         [0053]    In the illustrative embodiment shown in  FIGS. 1-6 , during each interval of approximately 1-2 seconds wherein the package is at a sub-location within the primary location C, each of the six galvos  110  may be controlled to mark on a respective one of six eggs in a given row. Accordingly, in some implementations, each galvo  110  may have approximately 1-2 seconds to complete the marking on each egg  205  for which it is responsible. As shown in  FIGS. 5A and 5B , one or more sensors (e.g., photo eyes  216   a - b ) may be used, either alone or together with a belt tick monitor or the like, to track the precise position of the egg package  204  with respect to the galvos  110 . 
         [0054]    In some embodiments, a vector-based process may be used to laser mark on the eggs  205 . In other embodiments, however, a dot matrix, raster, or other laser marking process may additionally or alternatively be employed. In some embodiments, each egg  205  may be marked during the available marking interval of approximately 1-2 seconds. 
         [0055]    In some embodiments, the image to be marked on the eggs may be digitally processed (e.g., pre-distorted) in advance of lasing the eggs  205  to account for the actual or expected curvature of the eggs in question. Taking such a step may result in an image that does not appear distorted in spite of being marked onto a non-planar surface. 
         [0056]    In some implementations, one or more additional laser sources and/or galvos may be also be arranged and configured to mark on one or more different portions of the egg, e.g., a back side, in addition to the front-side location discussed above. In some embodiments, for example, it may be desirable to mark certain information of immediate importance to a consumer, e.g., an expiration date and/or brand identification, on a front portion of the eggs so that such information is immediately visible to a consumer upon opening the box, and to mark other information of less immediate importance, e.g., tracking codes or the like, on the back side of the eggs. 
         [0057]    As shown in  FIGS. 5A and 5B , after the laser marking process is complete for a given package  204 , the conveyor  202  may move the package  204  to a location D at which a vacuum  218  nozzle connected to a vacuum source (not shown), together with a blower nozzle  220  connected to a air source (not shown), may be used to remove dust generated by the lasing process and any other unwanted particles from the packages of eggs before they are closed by the package closing section  208  of the egg packer  200 . In some embodiments, the vacuum source and/or the air source may be located apart from the laser marking apparatus  100  (e.g., on a roof of a building in which the apparatus  100  is located) and connected to the nozzles  218 ,  220  via appropriate tubes or ductwork (not shown). 
         [0058]    In some implementations, a machine vision system  146 ,  148  (shown in  FIG. 1 ) may be configured and arranged so as to examine the position and/or characteristics of the eggs that are to be marked and/or the quality and integrity of the information that is marked onto the eggs. As shown in  FIG. 1 , in some embodiments, one or more machine vision observation units  146  may, for example, be disposed adjacent beam projectors  148  of one or more galvos. In other embodiments, the one or more observation units  146  may be located elsewhere to allow for adequate observation. The one or more observation units  146  may be connected to one or more machine vision inspection system computers  148  using any suitable technique. Each of the one or more machine vision inspection computers  148  may be local to the system  100  or may be in a remote location. 
         [0059]    The egg processing system in question could, for example, be stopped if the machine vision system determines that the mark quality has fallen below a certain threshold. Such a system may be closed-loop in some embodiments, such that feedback from the machine vision system may be used to control the galvos  110  and/or the laser sources  104  so as to improve the quality and reliability of the process. For example, feedback from a machine vision system might adjust the number of passes made by the galvos, the rate at which the galvos scan, the power level of the laser, etc., in order to ensure a desired contrast level is achieved during the laser marking process. Additionally or alternatively, a machine vision system may examine the size, color, or other perceptible properties of the eggs to be marked and make appropriate adjustments to the laser marking components and/or process to account for such variables and thereby ensure that image quality stays consistent in spite of such variations. 
         [0060]    In some embodiments, it may be useful to allow for centralized control and monitoring of the operation of multiple different laser marking apparatuses  100  distributed throughout one or more facilities.  FIG. 9  illustrates an example of a system that would allow for such centralized control. As shown, respective groups of laser marking apparatuses  100  may be coupled to corresponding facility computers  222  so as to allow the facility computers to control the queuing of laser marking jobs to the control boards  111  of the various laser marking apparatuses  100  as well as to monitor the health and status of such apparatuses. Laser marking apparatuses  100  may thus behave essentially as network printers for the facility computers  222 . Each facility computer  222  may, for example, be located at a respective egg processing facility. 
         [0061]    Central server  224  may, in turn, be coupled via a network cloud  226  to the group of facility computers  222  to allow the central server  224  to distribute laser marking jobs to the various facility computers  222  and to monitor the status of those jobs. The network cloud  226  may comprise any of a number of network types, and may be distributed either over a local or wide area. In some embodiments, the network cloud  226  may, for example, comprise the Internet. When facilities are located in different geographic regions, different laser marking jobs may, for example, be distributed to the facility computers  222  at the different facilities depending on the region. If, for example, Major League Baseball decided to contract to have team logos marked on eggs, instructions could be sent to the facilities that distribute eggs to the New England area to mark the logo of the Boston Red Sox on a given number of eggs at those facilities whereas instructions could be sent to facilities that distribute eggs in the state of Florida to mark the logo of the Florida Marlins on a certain number of eggs at those facilities. 
         [0062]    In some embodiments, the galvos  110  may be independently controlled such that different images may be marked on different eggs in the same package. For example, the galvos  110  could be controlled such two eggs in a first row of a package have the letters “G” and “O” marked on them and six eggs in the second row of the package have the letters “R,” “E,” “D,” “S,” “O,” and “X” marked on them. In some embodiments, each egg  205  may even be marked with a unique identifier that allows it to be differentiated from every other egg that is laser marked using the system. 
         [0063]    Having thus described certain embodiments of systems and methods for practicing aspects of this invention, it is to be appreciated that various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and scope of the invention. For example, in embodiments wherein open egg packages are fed in the opposite direction onto the conveyor  202  shown in  FIGS. 5A and 5B , i.e., such that the receptacle section leads the lid section, the loop-wise movement of the egg orienter  112  may be unnecessary, as the appropriate orientation of the eggs within the package  204  could be achieved simply by allowing the open packages of eggs to pass underneath the egg orienter  112  (with or without causing it so shimmy slightly from side-to-side to help overcome friction). In such embodiments, because the tops of the eggs  205  would be caused to be tilted slight to the right (as depicted in  FIG. 5B ), it would also be desirable to orient the galvos  110  so that they face slightly toward the back of the conveyor  202 , thus allowing them to mark onto the large exposed surface area  230  of the eggs  205  obtained using this alternative technique. Accordingly, the foregoing description and drawings are by way of example only.

Technology Classification (CPC): 1