Abstract:
An automated de-banding machine which can perform by scanning the surface of the pallet to determine the number and position of bands to be removed. The machine also is capable of analyzing to determine the overlay bands from underlay bands. The overlay bands are removed first and typically fed individually to a chopper which chops the bands into pieces for recycling. The band information may be recorded and used to facilitate handling of a similar type of pallet in future operations to eliminate any stoppage for determination of retooling or adjustment.

Description:
TECHNICAL FIELD  
         [0001]    The invention relates to machines and processes used to automatically cut, remove and dispose of bands used to secure goods upon shipping pallets.  
         BACKGROUND OF THE INVENTION  
         [0002]    The packaging industry commonly uses pallets which have goods stacked thereon which are secured in position by a plurality of pallet bands. These bands vary in number and position depending upon the type of goods and techniques used to create and band the pallets. In the past it has been typical that pallets from one location or facility are different from those made up at another facility. This has made the removal of the pallet bands by the user more difficult.  
           [0003]    Some prior machines have been developed for automated de-banding (hereinafter “debanding”) of pallets. These machines have previously used a movable cutter head which moves over or along the pallets and cuts the bands. These prior machines have suffered from a number of problems.  
           [0004]    One significant problem arises because the pallet bands may not be in the same positions from pallet to pallet. Most prior debanding machines use pre-programmed band positions to control the machine. When a pallet arrives that does not have the bands positioned as pre-programmed, then the machine may malfunction and human operator intervention will be required.  
           [0005]    When the pallets are from the same or a similar source the banding positions may be variable but typically workable on an automated basis. However, when they are from different sources then the variations may be problematic enough that operations are hampered or prevented. In some situations the variations in the pallet band patterns generated by the same machinery are sufficiently problematic to be unworkable. In the past substantial operational assistance has been needed to keep debanding machines operational due to band positioning variations.  
           [0006]    Another notable problem has been the difficulty arising if the overlay and underlay relationship of the bands changes for any reason. The overlay and underlay relationships between the various bands used on a pallet are important during removal because the bands may become entangled if not removed in the proper order. Although pallets may have bands which are in a similar positional relationship and have similar numbers of total bands, they may be shipped with varying overlay and underlay relationships between the longitudinal bands as compared to the transverse bands. Prior machines necessarily assume that the overlay/underlay relationship of the bands was the same for all pallets using the pre-programmed settings. Such pre-programmed setups required substantial amounts of time. Additionally, it may be that pallets from the same facility having the same type and band patterns may not have the same overlay/underlay relationships from one pallet to another. This necessarily causes substantial problems in automated processing of the pallets to deband the pallet for subsequent depalletization.  
           [0007]    One prior approach to solving the underlay/overlay problem has instead used a system which cuts all bands simultaneously. This approach is may solve the underlay/overlay problem, but again is highly susceptible to any variations in the band pattern. If a different type of pallet is being processed, then substantial setup time and costs are needed to address the changed conditions.  
           [0008]    These and other problems have not been fully and adequately addressed by the prior debanding machines. Other problems and considerations may become evident in the future as this invention is used more or further develops. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    Preferred embodiments of the invention are described below with reference to the following accompanying drawings.  
         [0010]    [0010]FIG. 1 is a perspective view showing a preferred debanding machine according to the invention.  
         [0011]    [0011]FIG. 2 is a top diagram view showing one possible pallet configuration having bands extending over the top of the pallet.  
         [0012]    [0012]FIG. 3 is a top view of another pallet configuration wherein there is a band pattern which is used to secure a top frame just below the bands.  
         [0013]    [0013]FIG. 4 is an enlarged view showing a portion of the machine of FIG. 1.  
         [0014]    [0014]FIG. 5 is an enlarged view of a detailed portion of the embodiment of FIG. 1.  
         [0015]    [0015]FIG. 6 is a further detailed perspective view showing another portion of the embodiment of FIG. 1.  
         [0016]    [0016]FIG. 7 is a further detailed perspective view showing another portion of the embodiment of FIG. 1.  
         [0017]    [0017]FIG. 8 is a front elevational view showing the embodiment of FIG. 1.  
         [0018]    [0018]FIG. 9 is a right side elevational view of the embodiment of FIG. 8.  
         [0019]    [0019]FIG. 10 is a left side elevational view of the embodiment of FIG. 8.  
         [0020]    [0020]FIG. 11 is a rear elevational view of the embodiment of FIG. 8.  
         [0021]    [0021]FIG. 12 is a top view of the embodiment of FIG. 8.  
         [0022]    [0022]FIG. 13 is a perspective view showing a portion of the frame and movable head operating assemblies used in the embodiment of FIG. 1.  
         [0023]    [0023]FIG. 14 is a top view of the subassembly shown in FIG. 13.  
         [0024]    [0024]FIG. 15 is a rear elevational view of the subassembly shown in FIG. 13.  
         [0025]    [0025]FIG. 16 is a left side elevational view of the subassembly of FIG. 13.  
         [0026]    [0026]FIG. 17 is a front elevational view of the subassembly of FIG. 13.  
         [0027]    [0027]FIG. 18 is a sectional view taken along line  18 - 18  of FIG. 16.  
         [0028]    [0028]FIG. 19 is a bottom view of the subassembly of FIG. 13.  
         [0029]    [0029]FIG. 20 is a sectional view taken along line  20 - 20  of FIG. 17.  
         [0030]    [0030]FIG. 21 is a diagrammatic view showing a portion of a pallet and portions of a movable head and chopper forming a part of the debanding machine of FIG. 1.  
         [0031]    [0031]FIG. 22 is similar to FIG. 21 with the movable head portions illustrated repositioned, such as to insert a cut band into the band chopper.  
         [0032]    [0032]FIG. 23 is an enlarged perspective view showing detail from FIG. 21.  
         [0033]    [0033]FIG. 24 is an enlarged view showing detail from FIG. 22.  
         [0034]    [0034]FIG. 25 shows a perspective view of a movable head portion of the debanding machine of FIG. 1 in isolation with the viewer&#39;s perspective looking into the cutter and gripping jaws.  
         [0035]    [0035]FIG. 26 is an enlarged perspective view of the subassembly of FIG. 25 shown from the rear of the subassembly.  
         [0036]    [0036]FIG. 27 is a further perspective view of the subassembly of FIG. 25 shown from another oblique rear viewing angle.  
         [0037]    [0037]FIG. 28 is a bottom view of the subassembly of FIG. 25.  
         [0038]    [0038]FIG. 29 is a sectional view taken along section lines  29 - 29  of  
         [0039]    [0039]FIG. 30 is another perspective view of the subassembly of FIG. 25 shown from a further viewing perspective generally from the lower rear of the movable head.  
         [0040]    [0040]FIG. 31 is a perspective view showing the preferred chopping mechanism included as part of the debanding machine of FIG. 1 in isolation.  
         [0041]    [0041]FIG. 32 is another perspective view showing the chopping mechanism subassembly of FIG. 31 viewed from an alternative angle.  
         [0042]    [0042]FIG. 33 is a top view of the subassembly of FIG. 31.  
         [0043]    [0043]FIG. 34 is a side view of the subassembly of FIG. 31.  
         [0044]    [0044]FIG. 35 is a side view opposite from that shown in FIG. 34 of the subassembly of FIG. 31.  
         [0045]    [0045]FIG. 36 is an end view of the subassembly of FIG. 31.  
         [0046]    [0046]FIG. 37 is an end view opposite to that of FIG. 36 of the subassembly shown in FIG. 31.  
         [0047]    [0047]FIG. 38 is a schematic block diagram of the controller and relationship to key components.  
         [0048]    [0048]FIG. 39 is a process flow diagram.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0049]    Introductory Note  
         [0050]    The readers of this document should understand that the embodiments described herein may rely on terminology used in any section of this document and other terms readily apparent from the drawings and language common therefor. This document is premised upon using one or more terms with one embodiment that will in general apply to other embodiments for similar structures, functions, features and aspects of the invention. Wording used in the claims is also descriptive of the invention. Terminology used with one, some or all embodiments may be used for describing and defining the technology and exclusive rights associated herewith.  
         [0051]    Debander of FIG. 1 Generally  
         [0052]    [0052]FIG. 1 is a perspective view showing a preferred embodiment of debanding machine  10  according to this invention. Debanding machine  10  is preferably used in conjunction with conveyor  20 . Conveyor  20  is not a part of the invention but instead supplied by the facility at which debanding of pallets is to take place. Conveyor  20  may be constructed according to a variety of different designs. The size of the debander must be sufficient to allow use with a particular conveyor.  
         [0053]    As shown, conveyor  20  is a power driven, roller conveyor which moves the pallets from the right side as shown in FIG. 1 towards the left side. Pallet movement into and away from the machine preferably occurs along the X-axis as indicated in the accompanying legend shown in FIG. 1.  
         [0054]    [0054]FIG. 1 also shows a pallet  30  positioned within the debanding machine. The pallet is positioned at a receiver or receiving station which is advantageously within the framework of the machine as is explained next.  
         [0055]    Frame  
         [0056]    The debanding machine includes a frame or framework  40  which has a lower or base portion  41  and an upper or superstructure portion  43 . Framework  40  also includes a protective enclosure frame  45  which is connected to the upper framework  43 . The protective enclosure frame  45  is used to support safety panels (not shown) which are mounted about the upper portion of the machine to restrict access to the movable components of the debanding machine during operation. There are also additional frame parts that may be used to support various individual or subassemblies of the machine that are apparent from the drawings and/or described hereinafter. Specific description of some of the components of the various frame sections will now be considered in greater detail.  
         [0057]    The frame base portion or lower frame  41  advantageously includes support posts, such as the four base corner posts  51 - 54 . It is alternatively, possible to use three support posts to facilitate easy cleaning around the machine. Suitable modifications to the frame would be needed to accomplish this, but it is an alternative. It should also be appreciated that a variety of frame configurations are possible and may be needed to meet particular installation requirements.  
         [0058]    The lower frame corner posts are advantageously provided with feet  55 . Feet  55  preferably have footplates  56  through which apertures  57  may be provided in order to place mounting fasteners (not shown). The mounting fasteners may be extended into a concrete slab or other supporting structure upon which the debanding machine  10  is mounted. The debanding machine is preferably securely affixed to the supporting building structure to prevent movement of the machine during operation.  
         [0059]    The lower framework  41  also preferably includes front lower member  61  and front upper member  62  which are both shown horizontal and extend between the front left and right corner posts  51  and  52 . Similarly, the rear of the debanding machine is provided with a lower horizontal frame member  63  and upper horizontal frame member  64 , both of which extend between the rear corner posts  53  and  54  (corner post  53  not shown in FIG. 1).  
         [0060]    The lower framework  41  may further be provided with temporary frame struts (not shown) which extend between the front and back corner posts for use during shipping and setup of the machine but which are removed during operation. These stabilize the machine until such time as the footplates are secured to the supporting floor.  
         [0061]    As indicated above the frame includes an upper framework which is connected to the lower frame  41 . The upper framework includes four corner posts  71 - 74  which preferably are adapted to detachably fasten to the upper ends of the lower framework corner posts  51 - 54  using complimentary mounting flanges and suitable fasteners.  
         [0062]    The upper ends of the upper framework corner posts  71 - 74  are preferably connected by front-to-back upper framework transverse members  75  and  76  which extend between the corner posts and are affixed thereto. Upper frame longitudinal members  77  and  78  extend between the left and right upper corner posts  71  and  72 , and  73  and  74 , respectively.  
         [0063]    The above principle members of the upper framework provide the basic structural frame for the upper frame subassembly. In addition to the primary upper frame structural members, there are additional framework members associated with the safety enclosure frame  45 . Safety enclosure frame  45  can advantageously include top panel support posts  81  which extend upwardly and have mounting plates  82  at the upper ends thereof for resting a top horizontal safety panel thereon. Support plates  82  can include fastener holes  83  for securing the safety panel in position thereon.  
         [0064]    Safety framework  45  also preferably includes upper perimeter members  84  which extend about all four sides along the upper portion of the safety framework. Additionally, the safety framework includes vertical safety framework pieces  86  at a number of positions about the machine which are used to provide additional support for the preferred transparent safety panels being supported thereby. The lower edges of the safety panels are supported by lower horizontal safety frame members  87  which extend also along all four sides of the safety framework  45 , which are at different elevations over the entrance and exit portals to the pallet receiver.  
         [0065]    Pallet Receiver  
         [0066]    Framework  40  preferably includes a pallet receiving space  137  which is accessible through portals  138  and  139  defined between the front and rear corner posts  51  and  54  and  52  and  53  for the left and right ends of the debanding machine as shown in FIG. 1, respectively. The entrance and exit portals allow entrance and egress of the pallet  30  into and from the receiver formed within the framework and below the transverse frame pieces  75  and  76 . Where the safety enclosure frame is included, the portals are possibly further restricted in height, such as illustrated in the Figs.  
         [0067]    Pallets  
         [0068]    [0068]FIGS. 2 and 3 show two different exemplary pallets with associated pallet band configurations. FIG. 2 is a top view of a pallet  34  having empty beverage containers  35  held in several layers. The layers are divided by layer partitions (not shown). FIG. 2 also shows an optional but exemplary top frame  36  which is superimposed upon the beverage containers. The top frame is restrained by longitudinal pallet bands  37  which run the long direction of the pallet. The top frame is also secured by transverse or cross bands  38  which run transversely across the pallet in the shorter dimension or width of the pallet. The bands typically will run in a complete loop around both the top frame, pallet contents and pallet bottom frame (not specifically illustrated in FIG. 2).  
         [0069]    In the pallet band configuration of FIG. 2 the transverse and longitudinal bands cross or intersect at a band junction. As shown, the longitudinal bands  37  overlay the transverse bands which underlay. This may be referred to as a longitudinal band overlay configuration.  
         [0070]    [0070]FIG. 3 shows a different pallet  39  which has similar features as pallet  34  and the same numbers are used for the same features. Pallet  34  of FIG. 2 has four (4) bands in both the transverse and longitudinal directions. Pallet  39  has only two (2) longitudinal bands  37  and three (3) transverse bands  38  except the transverse bands  38  are the overlay bands and the longitudinal bands  37  are the underlay bands. Thus the band configuration of FIG. 3 may be referred to as a transverse overlay band configuration.  
         [0071]    Although not typical, it is also possible to have band crossings which have different overlay/underlay relationships on the same pallet. This configuration is not specifically illustrated but is readily apparent from FIGS. 2 and 3. Such may be referred to as a mixed overlay/underlay band configuration.  
         [0072]    Pallet Hold-Down Clamps  
         [0073]    [0073]FIG. 4 shows the upper portions of the debanding machine of FIG. 1 in greater detail. In particular, FIG. 4 shows that the debanding machine preferably includes one or more pallet hold-down mechanisms or other pallet clamps or securing devices  100  which secure the pallet in a working position within the pallet receiver. As shown, the pallet clamp or other securement mechanism or mechanisms  100  includes four pallet hold-downs  101 - 104 . Hold-down  104  is not shown in FIG. 4 but is shown in FIG. 9.  
         [0074]    Attention should now be directed to FIG. 6 which shows pallet hold-down  101  in greater detail. Pallet hold-down  101  includes two pallet hold-down guide rods  106  and  107  which are coupled to a base member  108 . A linear actuator  109  extends in parallel to and positioned between the guide rods  106  and  107  and is used to power the base plate  108  upwardly and downwardly. An engagement bracket or piece is connected to base plate  108  and is labeled  110  as best shown in FIG. 4. As can be seen in FIG. 4, the contact formed by bracket  110  is moved downwardly and against the upper corner of pallet  30  in order to engage the pallet and arrest its position within the debanding machine.  
         [0075]    Although each of the other hold-down mechanisms may vary in particulars, each has a contact  110  which similarly bears upon the pallet, preferably near the corners of the pallet, to simultaneously arrest all four corners and prevent motion of the pallet during the debanding operation performed by machine  100 .  
         [0076]    The pallet hold-down clamps are preferably provided with a safety feature that keeps the clamps at their upward, retracted position even if electrical power or pneumatic pressure is lost to the machine. This is advantageously provided in the form of hold-down clamp safety mechanisms  146  best illustrated in FIGS. 6 and 9. Safety mechanisms  146  include a pneumatic actuator  147  connected at one end to the frame and the other end drives a small pivotal lever arm  148 . The actuator  147  keeps the end of the lever arm from engaging under or otherwise with the end pieces  105  on guide rods  106  or  107 . A spring (not shown) or gravity force of the mechanism bias the lever into a latched position. The powered operation of the unit applies air to the actuators  147  that prevent latching unless power or pressure are lost in which case the actuators no longer apply force. When the actuators release the safety mechanisms latch until power and pressure are restored.  
         [0077]    Pallet Flow and Basic Operation  
         [0078]    Returning again to FIG. 1, pallets  30  enter from the right side of FIG. 1 and are moved into a debanding operating position as shown in FIG. 1 using the facilities conveyor  20 . The facilities conveyor is preferably controlled using a pallet position detector (not illustrated) that detects the position of the pallet and provides for the pallet to halt at the desired location within the debanding machine. Thereafter, the pallet hold-down mechanisms  100  are extended downwardly and brought into contact to arrest and secure the working position of the pallet.  
         [0079]    After the pallet has been stopped and secured, the general operation of debanding the pallet is performed as more fully described below. After the debanding operation has been performed, then the pallet hold-down mechanisms  100  are retracted and the pallet is once again conveyed by conveyor  20  out the exit portal  139  at the left as shown in FIG. 1 and onto other processing, such as depalletizing the load contained on the pallet.  
         [0080]    Overview of Control Structure  
         [0081]    [0081]FIG. 1 also shows a primary control interface box  121  which includes a visual display  122  and a number of control keys  123  which are used by the operator to provide control instructions to the debanding machine. The control system also advantageously includes at least one emergency stop switch  125 . As shown, there are two emergency stop switches  125  positioned near the rear left corner at upper and lower positions of FIG. 1 and on the control box  127 .  
         [0082]    The machine also includes a control wiring enclosure box  126  and a main control compartment  127  which are conveniently mounted to the framework at a suitable location, such as shown. A further control box (not shown) can be mounted to a control box support bracket  128  used to conveniently hold control wiring and junctures (not shown).  
         [0083]    Movable Operating Head—Generally  
         [0084]    Refer now to FIG. 21 which shows in relative isolation a movable debanding operating head assembly  200 . FIG. 23 shows the head in greater detail. It is also shown in many other Figs.  
         [0085]    The details of movable head assembly  200  will be discussed in greater detail below. At this point, the reader should appreciate that head assembly  200  is shown in FIG. 21 in a position ready to engage a pallet having a series of pallet bands  32  and  33 . Pallet  30  includes an upper frame piece  31  which extends about the top of the pallet and can be a perimeter frame or a full frame extending across the entire top of the pallet.  
         [0086]    The contents of the pallet are secured using longitudinal bands which extend along the length of the pallet. Bands  32  are oriented in the X-direction. Transverse bands  33  extend transversely across the pallet extending in the Y-direction. Underlapping and overlapping intersection or crossing points designated at  33  exist at the various crossing illustrated in FIG. 21 between bands  32  and  33 . Depending on the manner in which the pallet was made up, bands  32  may overlay or underlay bands  33 , as was discussed above.  
         [0087]    To automatically deband pallet  30  using machine  100 , the head assembly  200  moves to appropriate orientations and positions to sense the bands, engage the bands, cut the bands and relocate the bands, as will be more completely described below. The head assembly can be positioned so as to engage either the longitudinal or transverse bands by rotation of the movable head using a rotation stage and associated operator which will be described in greater detail below. The rotational stage is mounted upon a spacial positioning mechanism which provides for adjustable positioning along the X, Y and Z directional axes. The spacial positioning mechanism and rotational mechanism will be described in greater detail below.  
         [0088]    X-Stage  
         [0089]    The spacial positioning mechanism includes an X-stage and associated X-stage operator that moves the X-stage to a desired position along the X-axis. The X-stage is supported upon the machine frame and the X-stage operator moves the X-stage assembly relative to the frame.  
         [0090]    [0090]FIG. 4 shows that the frame includes a front guide rod  210  which extends longitudinally along the front of the debanding machine  10 , such as supported by the longitudinal frame member  77 . The guide rod is supported upon small support blocks which are between the rod  210  and frame member. A complimentary rear guide is used to support the opposing rear side of the X-stage assembly. This is advantageously provided in the form of a C-shaped guide rail  211 . Guide rail  211  is mounted to the framework, such as along the back of machine  100  upon the longitudinal frame member  78  using small support blocks extending between these components.  
         [0091]    Guide rail  210  is engaged by one or more linear slide blocks  212  which can be shown in greater detail in FIG. 7. Guide blocks  212  are used along the front guide rod  210  whereas rollers (not shown) are used with and positioned within the C-shaped guide channel  211  at the rear of machine to support the rear portion of the X-stage movable subassembly  220 . The X-stage subassembly  220  moves left and right as illustrated in FIGS. 4 and 7 along the guides  210 ,  211  to assume various X-positions needed to position the movable head assembly  200  to engage the bands and otherwise perform the actions indicated herein.  
         [0092]    X-Stage Operator Mechanism  
         [0093]    The X-stage includes an X-stage operator which operates the X-stage subassembly into various positions. The X-stage operator is driven by an X-stage servo motor  222 . X-stage servo motor  222  has an output shaft which is directly coupled into a X-stage gear box  224 . X-stage gear box  224  is mounted upon the frame and includes bearings to support output shafts which extend out towards the front and rear of the gear box. As shown, the front output shaft of gear box  224  is fitted with a front drive sheave  216  which is used to drive and support a front X-stage drive belt  228 .  
         [0094]    The rear output shaft from gear box  224  is used to drive a transverse X-stage drive shaft  230 . The rear end of drive shaft  230  is supported by bearing  231  mounted on the frame. Drive shaft  230  also mounts a rear drive sheave  232  which is used to drive a rear drive belt  233 .  
         [0095]    The opposing ends of drive belts  228  and  233  are trained about supporting sheaves  235  held by bearing blocks  236  which are fastened or otherwise suitably mounted on the frame. FIG. 6 shows this in greater detail. FIG. 6 also shows that secondary guide sheaves  241  can be mounted to the frame in order to position the drive belts over the hold-down actuators  100 , as needed.  
         [0096]    The upper runs of the drive belts for the X-stage are coupled to their respective ends of the X-stage support platform using drive belt connection fixtures shown most clearly in either FIG. 7, or alternatively in FIG. 5. The drive belt connection fixture includes a belt coupling  240  and associated coupling bracket  242 . The belt coupling  240  is fastened to the underside of the coupling bracket or piece  242 . The drive belts  233  or  228  are captured between mating pieces of coupling  240 . This is accomplished using fasteners (not shown). The coupling bracket  242  connects to the X-stage platform using fasteners which extend through apertures  244 , (fasteners not shown).  
         [0097]    Motion of X-stage drive motor  242  causes the drive belts to be moved thus causing each end of the X-stage platform to be simultaneously moved similar amounts. This drive configuration thus helps to minimize racking and mislocation of the X-stage platform relative to the frame and supporting guides  210  and  211 .  
         [0098]    The X-stage platform is advantageously constructed to slidably support a Y-stage platform  280  and associated operator. The Y-stage platform  280  is shown in detail in FIG. 5. Y-stage platform  280  includes slide blocks  281  which are arranged to engage with Y-stage support rods  271  and  272  which form a part of the X-stage platform structure. Guide rods  271  and  272  are mounted by end plates  273 . The opposing front and rear end plates  273  are connected by two transverse X-stage platform chassis members  274  and  275 . X-stage chassis members which act as the main transverse members extending between the X-stage support guides  210  and  211 .  
         [0099]    [0099]FIG. 5 further shows that the X-stage platform is provided with a Y-stage operator or drive mechanism  300  which will be detailed below.  
         [0100]    [0100]FIG. 5 still further shows that the X-stage platform structure may include a cable guide support channel  284  and associated cable guide  285 . Cable guide  285  is a flexible mechanism similar to a chain in appearance that encloses and protects cables yet allows them to flex as a combined unit to allow relative movement. In this case cable guide  285  allows movement between the cables on the X-stage and Y-stage. Electrical and control cables (not shown) are supported within the cable guide  285  to provide electrical power, air power and control information between the X-stage platform and the Y-stage which is movable relative thereto.  
         [0101]    [0101]FIGS. 4 and 7 show that the X-stage is supplied with electrical power, air power and control cabling using another cable guide  231  which is supported by a cable guide support channel  332  mounted on the frame using an ancillary cable guide support framework  333 . Cable guide  331  moves in response to longitudinal movement of the X-stage platform helping to maintain the various electrical, pneumatic and control cables in a desired constrained configuration.  
         [0102]    Y-Stage Platform  
         [0103]    As briefly explained above in connection with FIG. 5, the Y-stage includes a Y-stage platform  280  supported in slidable relation to the X-stage. This is advantageously done using slide blocks  281  which are at four corners of a platform plate  287 . Y-stage platform plate  287  is used to support a vertical or Z-stage and associated operator generally referred to as  350  which will be detailed below.  
         [0104]    Y-stage platform  280  also includes a mounting bracket  289  which serves as a Y-stage operator drive connection. The Y-stage operator drive connection further includes a complimentary coupling  290  which is fastened to connection bracket  289  using fasteners which extend through the apertures illustrated in FIG. 5. Parts  289  and  290  are thus secured to the Y-stage drive belt  292 . Drive belt  292  is moved so as to position the Y-stage at various transverse positions along the supporting slide bars  271  and  272  forming part  1   i  of the X-stage platform.  
         [0105]    Y-Stage Operator  
         [0106]    [0106]FIG. 4 shows that the X-stage platform also supports a Y-stage drive motor  301  which is mounted to the X-stage platform using suitable brackets  302  and  303 . The drive motor  301  has an output shaft (not illustrated) which is coupled to a Y-stage drive gear set  305 . Y-stage gear box  305  is mounted on brackets  302  and  303 . A depending output shaft from gear box  305  mounts a primary sheave  308  which is used to support and drive the Y-stage drive belt  292 . The rear end of drive belt  292  is supported using a secondary or idler sheave  293  illustrated best in FIG. 5. Sheave  293  is supported by pillow block support bearings  312  mounted using a drive belt extension bracket  313 . Rotation of the motor  301  causes the Y-stage drive belt  292  to move in either direction rotating the supporting sheaves and moving the Y-stage drive belt coupler  289  to relocate the Y-stage platform  280  to a desired position.  
         [0107]    Z-Stage Subassembly and Operators—Generally  
         [0108]    Debanding machine  10  preferably includes at least one Z-stage or vertical stage which is movable to adjust the vertical position of the movable head  200 . The preferred embodiment shown and described herein advantageously includes two Z-stage operators which serve in somewhat different capacities as will be detailed below. The Z-stage operators are generally referenced by number  350  in FIG. 5 and elsewhere. It may be suitable in some implementations of the invention to use a Z-stage which uses a single operator rather than the preferred two operators shown and described herein.  
         [0109]    [0109]FIG. 5 shows that the Z-stage subassembly includes two slidable guide rods  351  and  352  which are mounted through apertures  347  in the Y-stage platform piece  287 . The upper end of guide rods  351  and  352  are connected together using an upper guide assembly plate  355 . The guide rods and assembly plate  355  move vertically relative to the Y-stage platform. The guide rods  351  and  352  extend through the Y-stage platform downwardly to depend toward the receiver area in which the pallet is received and held during the debanding operations.  
         [0110]    The two operators used to move the Z-stage are a first or primary actuator which, as shown, is a pneumatic cylinder  360  having an extendible ram that is deployed beneath the Y-stage platform to lower the movable head  200 . The primary actuator  360  is used to make major adjustments of vertical position which are associated with adjusting the machine for a particular height of pallet. The second or secondary actuator is, as shown, another pneumatic actuator  521  which provides a smaller amount of vertical travel. The secondary actuator  521  is used after the pallet height has been determined and adjustment of the primary actuator has been made. The secondary actuator is used to make vertical height changes needed during movement of the head  200  during the cutting, gripping, and other operations associated with actual debanding operations.  
         [0111]    Z-Stage Primary Operator  
         [0112]    [0112]FIG. 5 further shows that the Z-stage primary actuator  360  is advantageously mounted upon the Y-stage platform piece  287 . The preferred pneumatic operator  360  is a pneumatic cylinder or ram having an actuated piston with attached output rod  361  (not shown in FIG. 5, see FIG. 15) which extends downwardly beneath the Y-stage mounting platform  287 . Gravity forces the weight of subassembly supported on the actuator output shaft downwardly. Air is controllably supplied to actuator  360  to raise the supported assembly, including movable head  200  upwardly.  
         [0113]    The primary Z-stage operator  360  has an external housing  366  which includes assembly rods  367  at each corner. The assembly rods are used  1   i  to connect opposing end plates  368  at the upper and lower end of actuator  360 .  
         [0114]    [0114]FIG. 20 shows the primary vertical actuator  360  with output rod  361 . Output rod  361  and associated guide rods  351  and  352  are connected to a vertical stage output mounting plate  362  which carries a rotational stage operator  420  which will be detailed below. The rotational stage operator  420  has an output shaft  421  which is connected to the movable head  200  to rotate the movable head over a suitable rotational arc, such as somewhat greater than 90°. This rotational capability is desired when positioning the head between orientations to cut the transverse versus longitudinal bands from a pallet.  
         [0115]    Z-Stage Secondary Operator  
         [0116]    The Z-stage also has a secondary actuator  521  which is advantageously a pneumatic actuator which extends and contracts to provide relative movement between the actuator housing and an output rod  522 . If left unclamped the output rod  522  would be moved downwardly in FIG. 5 with extension of the actuator, and upwardly with contraction of the actuator.  
         [0117]    The output rod  522  of secondary Z-stage actuator  521  is connected to a clamping tube  492  using a coupling  525  which is detachable from the output shaft  522 .  
         [0118]    The operation of the secondary operator will be given below after first describing the clamping mechanism with which the secondary actuator is used.  
         [0119]    Z-Stage Clamping Mechanism  
         [0120]    [0120]FIG. 5 shows that the upper end of actuator  360  serves to mount an elevational clamping mechanism  470 . Elevational clamping mechanism  470  is supported on a base plate  471  which is connected to the upper end piece  368  of actuator  360 . Alternatively, the clamping mechanism base plate may otherwise be supported in a stationary position.  
         [0121]    Clamping mechanism  470  includes a pneumatic or other suitable operator  472  which expands and contracts. Operator  472  has output connections  473  and  474  at opposing sides of the cylindrically shaped operator  472 . One output connection  473  is connected to a first arm  483 . The second output is connected to a second arm  484 .  
         [0122]    Clamping mechanism arms  483  and  484  are supported for pivotal action at fulcrum points or pivot axes  485  and  486 , respectively. The fulcrum points are kept at a defined spacing below the arms by the associated connection points on the base plate  471 . A retainer piece  487  also extends between the fulcrum points  485  and  486  to maintain the mechanical spacing thereof along the upper sides of arms  483  and  484 .  
         [0123]    The fulcrum points  485  and  486  have associated pivot shafts (not shown). The pivot shafts preferably are formed by bolts or other suitable shafts or pins. In the construction shown the pivot shafts are formed by bolts which simultaneously function as fasteners extending through the spacer plate  487  and into the base plate  471 . Bushings  489  are positioned about the shafts and act to maintain vertical positions of the parts so that added pressure does not bear upon arm pieces  483  and  484  when the assembly is made up tight.  
         [0124]    The clamping mechanism further includes contact jaws  491  which are expandable and contractible using operator  472 . Contact jaws  491  bear against clamping rod member  492 . The clamping jaws  491  are preferably pivotally mounted to the engagement ends of the arms  483  and  484  to bear against clamping rod  492  with better alignment.  
         [0125]    Operation of Z-Stage  
         [0126]    Vertical adjustment of the operational head  200  is provided by the Z-stage. Major movements are needed to sense the top of the pallet and to allow a range of pallet sizes to be processed. After a pallet has been placed in the receiver and secured in position, then the head is moved to a position where it can be used to sense the height of the pallet top. This is done by releasing pressure from the main or primary actuator  360  to thus allow it to drop under the force of gravity. The head  200  contacts the pallet and vertical movement stops. This acts to detect and determine the pallet height.  
         [0127]    After the head has contacted the pallet to thus determine the pallet height, then the clamping mechanism is employed to clamp rod  492  into a stationary position. Thereafter the secondary actuator is activated and is used to lift or lower the plate  355  and attached guide rods  351  and  352 . The plate is lifted when the secondary actuator  521  is extended because the rod  492  is clamped in a stationary position. The plate is lowered when the secondary actuator  521  is contracted. The output rod  522  is stationary and the actuator house which is attached to the plate  355  moves. Since the attached guide rods  351  and  352  move upward and downward the output of the vertical stage moves the head  200  to the desired elevation.  
         [0128]    Z-Stage Safety Brake  
         [0129]    The debanding machine  10  also preferably includes a Z-stage safety brake assembly shown in FIG. 5 by the reference number  600 . The safety brake assembly is mounted upon the Y-stage platform piece  287 . The safety brake  600  includes a base piece  602  which is secured to Y-stage platform piece  287  using suitable fasteners extending through fastener aperture  604 . Base piece  602  supports and actuator mount  608  which is secured thereto using a suitable means such as fasteners (not shown) which extend through apertures in the mounting piece  608  and secure it to the base piece  602 . The base piece and actuator mount include guide rod apertures therethrough referenced by numeral  610 . Guide rod  352  extends through such apertures and on through the Y-stage platform.  
         [0130]    The safety brake  600  also includes a safety brake actuator  620  which is a pneumatic ram as shown. Actuator  620  has an output shaft not visible in FIG. 5 which extends downwardly and connects with a tilting bind plate  630 . Bind plate  630  is mounted for tilting action on the opposite or rearward end of the assembly and is spring loaded in one direction using tilt plate spring  632 . Actuator  620  forces the tilt plate  630  into a position approximately parallel with the Y-stage platform thus aligning a guide rod aperture  633  so as to allow guide rod  352  to pass easily therethrough without binding action. Upon loss of pneumatic power to actuator  620 , then the action of biasing spring  632  causes the tilt plate to become angled and bind the guide rod  352  within aperture  633  to thus act as a brake and prevent any motion of the Z-stage movable assembly during a power outage or other shutdown condition.  
         [0131]    Movable Head Rotational Stage  
         [0132]    Rotational stage  420  is mounted upon the lower end of the Z-stage which controls the vertical elevation of the rotational stage. FIG. 16 shows this arrangement as does FIGS.  17 - 20 . Rotational stage  420  includes a rotational stage framework  423  mounted upon the lower output end of the Z-stage operator. Mounting piece or frame  423  mounts a rotational stage actuator  430  which is a pneumatic actuator coupled at one end to the rotational stage frame  423  and at the opposite end to a gear rack  432 . FIG.  20  shows that gear rack  432  engages with a pinion gear  433  which is mounted upon a rotational stage rotating assembly  434 . The rotational stage rotating assembly  434  is suitably mounted using bearings to the rotational stage frame  423 . As shown, this is accomplished using a bearing assembly  435 . The upper end of the rotational stage rotor assembly is supported by an upper bearing assembly  436 .  
         [0133]    When the rotational stage actuator  430  is activated, rack  432  moves and drives pinion  433  rotationally to pivot the output shaft  437 . The mechanism is preferably designed to have an arcuate range of motion of at least approximately 100°-110° so as to allow easy reorientation of the movable head  200  over a common traveling range of approximately 90° of arc.  
         [0134]    The rotational stage also includes a cable guide  439  which allows electrical, pneumatic and control cabling to neatly play out and be recoiled as the movable head  200  is rotated. Cable guide  439  does not rotate with the rotor of the rotational stage but is mounted upon the other components secured to the rotational stage mounting plate  362 .  
         [0135]    Operational Head Structure  
         [0136]    The debanding apparatus includes a movable operational head  200  which has a number of components which will now be described in connection with FIGS.  25 - 30 . The head includes a head frame  700  which is advantageously assembled from weldments and other parts which are securely affixed. As shown, head frame  700  includes a mounting plate  701  which is connected to the rotating output shaft from the rotational stage described above. Frame  700  also includes a second frame piece  702  which is connected to frame piece  701  and extends downwardly. Frame piece  702  includes a gusset piece  703  used to help secure a fourth frame piece  704 . A fifth frame piece  705  extends from second frame piece  702  and is used to mount a cutting assembly  720  in movable relationship to other portions of the movable head.  
         [0137]    Frame  700  may also include a variety of mounting brackets. Mounting brackets  711  is used to support a band detector not shown in  1   i  FIGS.  25 - 30 , but which is illustrated in other views and will be discussed in greater detail below. The frame further includes a second mounting bracket  712  also used to support a detector. A further frame bracket  713  is also provided to mount a proximity detector which is used to detect position and/or travel of the movable cutter assembly using a proximity switch or other suitable position detector (not shown).  
         [0138]    Frame  700  also mounts a contact pad  730  which is preferably fastened to frame piece  704  using fasteners which extend through apertures  731  and into frame piece  704 . Contact piece  730  is used when the movable head is extended downwardly to contact the top of the pallet  30  to detect the, pallet height. It also shields remaining portions of the head against direct physical contact with the pallet until specifically intended during operation of the head.  
         [0139]    Band Stationary Guide  
         [0140]    [0140]FIG. 25 best shows that movable head  200  includes a stationary band guide  740 . Stationary band guide  740  preferably has a band guide mount  741  which includes two converging band guide faces. The band guide faces include lower band guide face  742  and upper band guide face  743 . The iv band guide faces are preferably curved and converge inwardly to a band guide  1   i  slot  744 . Band guide slot  744  is advantageously provided with a boxed interior end with an abutment face against which bands come into contact when fully inserted into the stationary band guide.  
         [0141]    Band Gripper Assembly  
         [0142]    The movable head  200  further includes a band gripper assembly which is advantageously used to grip bands which have been positioned within the stationary band guide  740 . Band gripper assembly  750  includes gripper jaws  751  and  752  which are movable relative to each other in order to expand and contract. In the expanded mode, the pallet bands come within the opposing contact faces of the band jaws  751  and  752 . Upon contraction of the band jaws together, the bands are gripped and securely held therebetween.  
         [0143]    The band gripper  750  is used to hold the band during cutting and also to retain the band to the movable head  200  as the band is moved within the debanding machine so as to bring it into position to be processed, such as by the band chopper  500  which is detailed below.  
         [0144]    Band Cutter Assembly  
         [0145]    Movable head  200  includes a band cutter assembly  720  which is used to cut a band which has been properly engaged by the movable head The cutter assembly may be moved relative to the movable head frame  700  in a manner which extends and retracts the cutter assembly. FIGS. 23 and 25 show the cutter assembly extended outwardly. FIG. 24 shows the cutter assembly retracted.  
         [0146]    The band cutter assembly includes a cutter assembly actuator  723  which has associated guide rods  724  and  725  which guide and prevent rotation of the movable portions of the assembly when such are moved between the extended and retracted positions. Cutter assembly actuator  723  is advantageously a pneumatic actuator which has a body portion attached to head frame piece  700 . FIG. 26 shows a movable part  729 . Attached to the movable part  729  is a mounting plate  728  which supports the suspended portions of the cutter assembly.  
         [0147]    [0147]FIG. 23 shows the movable head  200  in position to engage a band and the cutter assembly portion of the movable head is extended. FIG. 24 shows the cutter head portion of the movable head retracted. This action of retraction is provided for so that the cutter assembly can be moved backwardly when a band is to be fed into the chopper as indicated in FIG. 24.  
         [0148]    The cutter assembly also and preferably includes two cutter guides  726  which have converging guide surfaces similar to the stationary guide  740  discussed hereinabove. Cutter assembly further includes a pincher or other cutting tool  760  which has two jaws  761  and  762  which are operated using a pneumatic operator  763  as illustrated in FIG. 26. Operator  763  is provided with controlled pneumatic pressure and pressure relief using cutter actuation lines  764  and  765 . Supply lines  764  and  765  are connected to a movable head pneumatic fitting mounting block assembly  766 . Lines  764  and  765  are preferably flexible so as to allow the cutting head assembly to move relative to the frame portion of the movable head. This occurs when moving between the extended and retracted positions discussed above. Line  764  and  765  can include detachable couplings or other connections  769  or other couplings as desired.  
         [0149]    Band Engagement Detector  
         [0150]    The movable head assembly  200  also includes a band detector which is used to detect when a band has entered the guides  740  and  726 . This is advantageously accomplished using a band detector mechanism which is mounted upon the cutter assembly which is movable relative to the head frame  700 . As shown, band detector  770  (see FIG. 25) includes a contact plate  771 . Contact plate  771  has a contact surface  772  which is along a nose or other appropriate point where a band entering the guides  740  and  726  will bear upon surface  772  and displace the detector plate  771 . The detector plate  771  is provided with the ability to move relative to other parts of the cutter assembly. As shown, this is accomplished using a plurality of mounting slot  775  to which are extended detection plate mounting fasteners  776  which may have retainer washers  777  included thereon. Detection plate  771  moves relative to fasteners  776 .  
         [0151]    [0151]FIG. 26 shows detection plate  771  from the rear of the movable head assembly. Detection plate  771  moves rearwardly as just explained in response to being contacted by a pallet band as the movable head is moved into engagement and the band becomes positioned within the guides. A mounting bracket  714  connected to the back of cutter assembly includes an extension arm  715  which mounts a proximity detector which is mounted using aperture  716  and detects the movement of plate  771  to indicate that a band has been properly received in the engaged position. This is used as part of the overlay analyzer as will be explained in greater detail below.  
         [0152]    Scanning Band Detector  
         [0153]    The debanding machine  10  is provided with at least one band detector for detecting the pallet bands  37  and  38 . The band detector may be an optical band detector  780  or an ultrasonic detector  781 . Detectors  780  and  781  are only illustrated in FIG. 25. Other views show merely the mounting brackets. It is possible to use one or both detectors to obtain information on the positions and numbers of bands present on the pallet.  
         [0154]    The preferred construction places the band detector or detectors on the movable head  200 . This allows the band detectors to detect the pallet bands by scanning as head  200  is moved across the pallet adjacent to the surface being reviewed. As shown, this is done by scanning the head across the upper or top surface of the pallet  30 . The head is preferably controlled to move at a slower speed when the detector is in the vicinity of a band. A band vicinity can be programmed into the controller, or it can be based upon band pattern information already stored in the debander control system.  
         [0155]    The band detector may employ optical detection technology, ultrasonic beam detection technology or other suitable units that have the ability to discern and discriminate a pallet band in a reliable fashion. A suitable optical detector is a Model SME312d manufactured by Banner Engineering Corp. of Minneapolis, Minn. A suitable ultrasonic detector is Model SM380A-228-00 manufactured by Hyde Park Electronics, Inc. of Dayton, Ohio. Other detectors now known or hereafter developed may be appropriate for use as the band detector.  
         [0156]    Band detector  780  can be mounted in a variety of locations upon  1   i  the head. As shown, optical detector  780  is mounted to a bracket  712 . Ultrasonic detector  781  is mounted in a mounting notch  782  (see FIG. 26) formed in the upper rear portion of contact pad  730 . The ultrasonic beam is directed from the ultrasonic detector through aperture  784  through the contact pad and reflected ultrasonic waves are bounced back and detected by detector  781 .  
         [0157]    Frame Detectors  
         [0158]    [0158]FIG. 25 shows a first frame detector  790 . Frame detector  790  is directed downwardly to detect the edge of a pallet and provide information to the control system indicating the edge position. Detector  790  can advantageously be an optical or other suitable detector. One acceptable type of detector is a photocell detector. A suitable detector is Model SME312D manufactured by Banner Engineering Corp. of Minneapolis. This model has adjustable background suppression capability which has been found desirable in some situations.  
         [0159]    The position of the pallet frame edge is determined by the readings given by the X-stage and Y-stage servo motors which have encoders included therewith that are read electronically. The information is stored in memory in the machine controller.  
         [0160]    The movable head may also be provided with an optional second frame detector  792 . Detector  792  is directed downwardly to sense the pallet top frame. Where employed, it may be which is used to detect the width of any top frame present on the pallet. As shown, frame detector  792  is an optical detector, but may be of alternative types or configurations.  
         [0161]    Other Detectors  
         [0162]    The receiving bay in which the pallets are secured may also be fitted with position detectors (not shown) which can be used to detect when a pallet is present and whether the pallet is of a minimum height. The detectors may employ a variety of detector types, such as light emitting beam detector pairs, or others.  
         [0163]    The debanding machine also preferably includes suitable detectors or sensors (not illustrated) which detect when the various movable assemblies have reached their desired positions. This is communication to the control system as a check on proper operation.  
         [0164]    Band Chopper  
         [0165]    The debanding machine  10  also preferably includes a band chopper  500 . FIG. 1 shows the general position of chopper  500  and the outflow or discharge chute  501 . The discharge chute is preferably angled outwardly from the chopper toward a discharge end. The discharge of the chute is preferably provided with a pivotal end section  502  which can be positioned in a receptacle or container (not shown) which receives the chopped pieces of bands  37  and  38  which are produced. The resulting pieces are typically recycled or otherwise disposed of. They may also be conveyed away from chute  501  using an air conveyor tube system present at the plant where machine  10  is installed.  
         [0166]    Refer to FIG. 31 which shows the band chopper assembly in isolation and greater detail. The band chopper has an infeed end  510  and a discharge  520  out the bottom of the unit. The end of a cut band is fed by the moving head  200  into a mouth assembly  530 . Also see FIGS. 21 and 22 concerning the general movement of the head toward the chopper and their relative positions in preparing to feed a band into the chopper.  
         [0167]    Chopper  500  also includes a motor  540  which is mounted on the opposite end from the infeed. Motor  540  drives several components including an internal cutter (not shown). The motor drives the internal cutter via a drive pulley  581 , drive belt  582  and cutter sheave  583 . Cutter sheave  583  is mounted upon a cutter rotor assembly  584 . The internal cutter is mounted upon the rotor assembly.  
         [0168]    Motor  540  is preferably adapted by providing a suitable braking is mechanism for slowing the motor to prevent long wind-down times which may present safety problems to mechanics working on the debanding machine. A preferred form of motor braking is provided in the form of a variable frequency electronic motor control which is configured to apply electric field braking when electrical power supplied to the motor is ended. This effectively applies a magnetic field or fields that attempt to slow the motor.  
         [0169]    Motor  540  also drives an infeed wheel which is used to engage an incoming band being chopped, comminuted or otherwise divided into pieces. The infeed wheel is mounted on an infeed wheel shaft which has a sheave  513  attached thereto. Sheave  513  is driven by a belt  585  which is also trained about a sheave mounted to the rotating assembly  534 .  
         [0170]    The chopper infeed section  510  also includes a pressure wheel  514  which is mounted for frictional engagement against the infeed roller  511 . Pressure wheel  514  is biased against the driven infeed roller  511  to thus apply force to a band being fed into mouth  530  and between rollers  511  and  514 .  
         [0171]    [0171]FIG. 34 indicates that the pressure wheel is preferably mounted for rotation at the end of a pivotal mounting arm  515  which has a pivot shaft  516  supported relative to the infeed mounting frame  519 . Biasing force is applied through the mounting arm using a pressure roll biasing spring  518  connected to the arm and the infeed mounting frame  519 . The biasing force provides drive friction between the infeed roller, pressure wheel and a pallet band being fed between them. This allows a band to be fed at a relatively fast rate so that the head assembly  200  does not delay longer than needed at the chopper station with each band being fed thereinto.  
         [0172]    [0172]FIG. 31 shows that the chopper infeed also includes a mouthpiece  532 . A guide  529  is used to assist in guiding incoming pallet bands into the mouthpiece. The mouthpiece is mounted to a rectangular feed tube  533  using mounting fasteners  534 . Mouthpiece  532  has replaceable guides  535  which are pressed into apertures  536 . Guides  535  act to guide the edges of bands being fed. They also act as replaceable wear parts that are preferably made of a wear resistant material, such as a suitable wear-resistant, hardened steel pin.  
         [0173]    The feed tube  533  is advantageously provided with compressed air fittings  537  at both sides of the tube. These fittings extend into the interior feed channel defined by the feed tube. The fittings have nozzles or opening interior to the feed channel to jet air into and down the throat of the feed tube and associated feed passage in the chopper to help prevent clogging of the feed tube.  
         [0174]    The central section  550  and many other parts of chopper  500  are commercially available from a suitable supplier, such as Sweed Machine of Gold Hill, Oreg.; Model 400 Quad. This construction has been found useful with the above with modifications and others as will now be described.  
         [0175]    The baseplate  551  of the central cutter section  550  is provided with a discharge assembly  560 . FIG. 34 shows that the discharge assembly  560  is provided with a funnel section  561  which attaches to the discharge opening within the baseplate  551 .  
         [0176]    Funnel section  561  has a piece detector mount  562  connected at the lower, discharge side of the funnel. Mount  562  receives and supports a detector  565  used to sense passage of flying pieces of pallet band which have been expelled by the cutter turning within central cutter section  550 . The pieces fall though an opening formed within the detector and interrupt multiple beams of light, infrared radiation or other detectable beams that are beamed across the detector&#39;s central opening to suitable photodiodes or other detectors positioned on the opposite side of the discharge passed within the detector. A suitable detection is a Model XUVF250M12 Telemecanique available from Schneider Electric, Palatine, Ill. The output from the detector is communicated via an electrical detector output signal coupling  566  which is connected to the control system. The signals from detector  565  provide confirmation that the chopper is properly discharging pieces. If the detector fails to detect band pieces then the discharge chute  501  may be plugged, the chopper cutter may be inoperable, or the band may be stuck on the pallet.  
         [0177]    The discharge section  560  also includes a lower flange  568  which interfaces with the discharge chute  501 . Outgoing or discharging band pieces pass therethrough.  
         [0178]    Control System  
         [0179]    [0179]FIG. 38 shows in block diagram schematic form the configuration for the control system  900  advantageously used in debanding machine  10 . The control system includes an alternating current (A.C.) power supply  901 . Supply  901  may be a three-phase nominal 230 volt 60 Hz supply from an electrical supply system mains.  
         [0180]    Alternating current from supply  901  is in part fed to a direct current (D.C.) power supply  902  used to provide a suitable D.C. voltage such as 24 volts. The electrical current from supply  902  is used to power a main controller  910  which may be a suitable programmable logic array or other  1   i  system controller capable of programming to perform the functions indicated herein.  
         [0181]    The system also includes a number of operator controls, such as from panel  121  or otherwise which are connected to the main controller to coordinate and sequence operations. Exemplary sensors are also shown and are connected to the main controller to provide information relevant to the conduct of the control process.  
         [0182]    Also shown are the X-stage and Y-stage servo motors which have associated positional encoders which are detecting position information of the movable head and sending such information to the main controller for processing with the control programming. The chopper motor variable frequency drive is controlled to provide operation of the chopper during periods when bands are being comminuted.  
         [0183]    Main controller  910  is also connected to indicator lamps that show various operations being performed by the debanding machine.  
         [0184]    The main controller also directs operations of the various components described above, and in particular are pictured in FIG. 38 the action of the gripper, cutter head, cutter and pallet clamps that are operated using electrically activated solenoid valves controlling supply of compressed air to the various pneumatic controls.  
         [0185]    Further Description of Operation  
         [0186]    In the above description a number of operational aspects have been described. Additional operational aspects are explained below. FIG. 39 shows notable steps in the procedure more fully described above.  
         [0187]    A pallet is moved into the receiver using the conveyor  20 . The position of the pallet is detected by suitable pallet position detectors, such as a beaming photodetector that is activated when the beam is broken by the pallet arriving at a suitable position. Once positioned, the pallet is secured by deploying the pallet clamps.  
         [0188]    After the pallet has been properly positioned and secured in the working position within the receiver, then the movable head is positioned by the head drive mechanism to detect the edge position of the pallet. This is preferably done by detecting the X-stage position first and then the Y-stage edge position is detected after moving the head with edge detector thereon. In most applications it is only necessary to detect one X-stage edge position and one Y-stage edge position. Alternatively, it is possible to detect the edge positions of all four top edges if desired.  
         [0189]    In the preferred methods the head is then moved to a suitable position to determine the height of the pallet being worked upon. This is typically done along the edge of the pallet. In greater particularity, the head may be moved to a position along the front of the machine near the chopper and then lowered by releasing air pressure from primary actuator  360  allowing it to drop under the force of gravity. The head comes to rest with the contact bumper  730  against the top of the pallet. The height information is now recorded by the controller but it could be. Instead, it has been found preferable to utilize the clamping mechanism explained above to clamp rod  492  and thus record the general pallet height. This height parameter is then used to generally establish the height range for subsequent operations. After the general height has been determined, the secondary actuator is operated to achieve desired height changes during operations on a specific pallet. Each pallet is assessed with regard to its height using this configuration.  
         [0190]    The band detector is then used to locate the position and number of the bands present on the pallet. This is advantageously done by scanning the head over the pallet and detecting each band using the band detectors as explained above. As the bands are detected the position of the head is recorded using the servo motor encoder information associated with a band detection position. This is stored in the controller memory for future use in controlling machine operation.  
         [0191]    It has been found preferable in some situations to have the moving head  200  operated in the band detection phase in two or more scanning speeds. This is done by having anticipated band locations and then moving more rapidly toward the anticipated band locations. Upon reaching a zone in proximity to the anticipated band location, the motors are controlled to move at a slower speed to improve the scanning detection capabilities of the machine.  
         [0192]    The above scanning band detection modes of operation are  0 . 19  performed for both the X and Y directions. In some preferred forms of the invention the Y-axis bands are scanned for first, followed by scanning the head to detect X-axis bands. The resulting information indicating the number and position of the bands is recorded in the controller.  
         [0193]    After the band scan of the pallet has been completed, then the head is raised to the up position by releasing the clamp mechanism and using the primary actuator. The head is then moved to the desired edge position near the first band cut location desired. In this position, the head is once again lowered to establish the pallet height. The clamping mechanism is clamped into engagement to establish the general working height. The secondary operator then is used for further height variations. At this point the head may be raised slightly to clear the pallet frame or other top surface.  
         [0194]    The head positioning mechanisms then move the head to the desired first cut position which is a function of the detected number and positions of the bands. In general the first band approached for cutting will be along one edge of the pallet and the bands are if possible pursued with the head in the same orientation.  
         [0195]    Concomitant with the approach to the first band the debander performs a procedure which performs the function of an overlay analyzer which determines whether the first band planned to be cut is an overlay band or an underlay band. If the first band intended to be cut is an overlay band, then the cutting operation proceeds. If the first band to be cut is an underlay band, then the control system adjusts the intended band and cuts the other intersecting band which is in actuality an overlay band. The machine needs to cut the overlay band first to prevent possible entanglement of the cut band as it is removed from the pallet.  
         [0196]    Overlay Analyzer  
         [0197]    The debanding machine preferably conducts a procedure and has structural features that act as a overlay analyzer. This is performed by engaging the head assembly  200  with the proposed band to be cut. The head assembly includes an overlay foot or contact  788  (FIG. 30) that bears upon the band running the same direction as the cutter is oriented and moving. Foot  788  runs along the band until it reaches a band crossing. If the proposed band to be cut (which is crosswise to the band along which the foot is running) is an overlay band, then the band guides  740  and  726  will engage and receive the band and the band will be detected by the band engagement detector  770 . If the band being approached is an underlay band, then the contact foot  788  continues along that band and the band guides  726  and  740  will not go into engagement with the crossing band being approached for cutting. The crossing band avoids guides  726  and  740  and will not be detected by band engagement detector  770 . This acts to discriminate the approached band as overlay or underlay.  
         [0198]    The controller is programmed that travel beyond a specified distance, such as 0.25 to 1 inch beyond the previously determined band position is indicative that the band refused to be taken up by the band guides  726  and  740  and thus the approached band was an underlay band.  
         [0199]    The controller is also programmed to then proceed by turning the rotating stage to the other orientation and to cut another band. The process of gripping and cutting the bands thus proceeds as described below.  
         [0200]    Gripping, Cutting, Relocation and Chopping Operations  
         [0201]    If the approached band is properly engaged, then the band engagement detector sensed the band and this is used as a condition in the control programming to then grip the band using the band gripper. The band gripper actuator is activated to close the gripper jaws and the band is engaged. The Cutting operation is then initiated by activating the cutter actuator causing the cutter jaws to cut the band thus severing the band at the cutting location.  
         [0202]    Once the band is cut, the gripper has hold of the band and the controller directs the movable head assembly to move to the chopper station. The gripped band is held and pulled toward the chopper. The cutter assembly is retracted to provide a free end of the band as indicated in FIGS. 22 and 24. The free end of the cut band is then inserted into the chopper mouth and the chopper is operated to cut the band into pieces as the band is pulled. The gripper is released to allow the band to feed into the chopper.  
         [0203]    Pallet Learning Storage for Subsequent Use  
         [0204]    Another aspect of the debanding machine is the ability to store or record the pallet band pattern information and use it on subsequent pallets. The band information from a first pallet may be used to either speed operations by providing expected band position information to a subsequent band scanning operation, or can be used directly as the band position information for a subsequent pallet of similar configuration. The band pattern information is kept in the controller memory and then recalled as if the scan information had been taken anew for the second pallet being operated upon.  
         [0205]    Interpretation Note  
         [0206]    The invention has been described in language directed to the current embodiments shown and described with regard to various structural and methodological features. The scope of protection as defined by the claims is not intended to be necessarily limited to the specific features shown and described because other forms and equivalents for implementing the invention can be made and in some cases this is done simple to evade the intended purpose of this document and any exclusive rights associated therewith.