Abstract:
Repositionable extendable stops for material handling applications include top loading/unloading stops which engage with actuator through quick disconnects. Actuators are easily repositioned to a new stop location, and the stop reconnected to the actuator by loading the stop through the top of the conveyor.

Description:
BACKGROUND 
     The present invention relates generally to material handling conveyors, and is particularly directed to a device and method which simplifies the location and relocation of stops for product flow control. The invention will be specifically disclosed in connection with positionable pop up stops used in a row former of a case palletizer. 
     In the world of material handling, case palletizers are machines that automate and speed up the creation of a palletized load by receiving loose cases or articles from a feed conveyor, forming the articles into formed layers with the row former, and stacking the formed layers onto a pallet with a layer-by-layer stacking process. Articles can include cases, cartons, and bags. In high volume factories, a case palletizer can be a custom product designed to palletize one article of one specific size. 
     This solution has some downfalls. The custom built case palletizer is specifically designed for one article and must be reconfigured to palletize an article of a different size or shape. With some articles, a simple reprogramming of the palletizer control system is adequate. With other articles, the palletizer must be re-programmed and physical elements of the palletizer must be physically re-built or re-configured. The rebuilding or reconfiguration process can result in: lengthy reconfiguration downtimes, high labor costs, and reduced palletizer throughput. 
     Although the present innovation will be described herein in connection with pop up stops for use with a row former, it will be understood that present innovation is not limited in use or application thereto. The teachings of the present innovation may be used in applications using any pop up stops that are desired to be location reconfigurable. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments, and, together with the general description given above, and the detailed description of the embodiments given below, serve to explain the principles of the present invention. 
         FIG. 1  is perspective view of a case palletizer. 
         FIG. 2  is a fragmentary perspective view of the upper level of the case palletizer illustrated in  FIG. 1 . 
         FIG. 3  is a diagrammatic plan view of the case palletizer illustrated in  FIG. 1 . 
         FIG. 4  is a top perspective view of a row former conveyor having stops constructed in accordance with the teachings of the present invention. 
         FIG. 5  is bottom perspective view of the row former conveyor of  FIG. 4 . 
         FIG. 6  is an exploded view of the row former conveyor and stops of  FIG. 4   
         FIG. 7  is an enlarged fragmentary cross-sectional view taken through a groove/slot interface. 
         FIG. 8  is an enlarged fragmentary perspective view m partial cross-section showing the quick disconnect between a stop and an actuator. 
     
    
    
     Reference will now be made in detail to the present preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings. 
     DETAILED DESCRIPTION 
     The innovation disclosed and claimed herein, in one aspect thereof, comprises a pop up stop that is easily re-positioned to a new location. The pop up stops are located in a row former of a case palletizer. The row former includes a roller conveyor that receives an input of articles from a feed conveyor. One or more pop up stops can be located beneath the roller conveyor, and each pop up stop can be individually actuated to extend a barrier through a gap between the rollers. When the barrier is extended, an article traveling along the row former is stopped by the barrier. As subsequent articles are inputted into the row former, the pop up stops are activated sequentially to form a row of spaced-apart articles along the row former. 
     When the row of articles is fully formed, the formed row is then moved from the row former and further into the palletizer to become part of a formed layer of articles on a pallet. The pop up stops are designed to be rapidly and easily re-positioned in the conveyor to change the spacing between the articles formed in a spaced-apart row. This enables a palletizer to be easily re-configured to operate with a different sized article. To re-configure a palletizer to operate with different sized articles, the pop-up stops can be easily re-positioned. To change number of articles in a row, the number of pop-up stops can be easily increased or decreased. 
     The present innovation can provide features and benefits such as (i) rapid re-positioning of pop-up stops to reduce palletizer re-configuration downtimes; (ii) modularized pop-up stops minimize the need for custom components; (iii) reduced labor costs from reduced reconfiguration downtimes time; (iv) increased palletizer throughput; (v) replaces hard hydraulic lines with flexible hydraulic lines to allow movement of the pop up stops to other positions; (vi) provides wiring of sufficient length to allow movement of pop-up actuators without wiring modifications; and (vii) the modular design easily accommodates an increase or decrease in the number of pop up stops in a row to change the number of cartons in a formed row. 
     In the following description, like reference characters designate like or corresponding parts throughout the several views. Also, in the following description, it is to be understood that terms such as front, back, inside, outside, and the like are words of convenience and are not to be construed as limiting terms. Terminology used in this patent is not meant to be limiting insofar as devices described herein, or portions thereof, may be attached or utilized in other orientations. 
     Referring to  FIGS. 1 and 2 , there is shown case palletizer assembly, generally indicated at  2 , which includes an upper level  100  that receives a steady stream of articles  10  from an input conveyor  110  and a lower level  200  that discharges a palletized load  120  of articles  10  onto an exit conveyor  130  for shipping. The upper level  100  receives, collects, organizes, and forms the loose articles  10  into a formed layer  110  on top of a pair of elevator doors  140 . The lower level  200  receives the formed layer  110  when the elevator doors  140  open, and builds up the palletized load  120  layer-by-layer on a pallet  214  until the palletized load  120  is ready for shipping. The lower level  200  can include an elevator  210  with a lift  212  that moves the pallet  214  vertically to collect the formed layers  110 . The lift is movable between a first position located directly below the elevator doors  140  to receive the formed layer  110  from the first level  100 , and a second position level with the exit conveyor  130  to discharge the palletized load  120 . 
     Referring to  FIGS. 2 and 3 , there is shown a top view of the upper level  100  of the case palletizer assembly  2  which includes a row former  4 , a layer table  6 , and an apron  8 . In a manner well known in the industry, a directed onto row former  4  that includes a roller conveyor  5 . When entering an empty row former  4 , the lead article  10 A is advanced thereon until it reaches an end barrier  12 , which stops further advancement. End barrier  12  may be adjustable, so depending on the pattern being built, end barrier  12  may be disposed upstream or downstream of the illustrated location, so long as there is a roller  14  proximal to barrier  12 . Once article  10 A reaches barrier  12 , a stop  16  may be raised so that it stops the next successive article  10 B. Similarly, a stop  18  may then be raised, stopping the advancement of article  10 C, followed by the raising of a stop  20 , stopping the advancing article  10 D. Although one article per stop is illustrated, the number of articles per stop may be any number to the article dimensions and the pattern being built. For example, for articles having different lateral and longitudinal dimensions, some may be turned before reaching row former  4 . 
     Once a row is formed, a row pusher bar  22  advances laterally (relative to the downstream direction of row former  4 ) and pushes the row,  10 A,  10 B, I 0 C and  10 D, onto layer table  6 . Pusher bar  22  can include notches  22   a  that clear the raised stops  16 ,  18 ,  20  as pusher bar  22  moves laterally. Layer table  6  may have an upper surface defined by rollers  7  disposed transverse relative to rollers  14  of former  4 , and may be declined away from row former  4 . Once row pusher bar  22  has advanced far enough, additional articles may be directed onto row former  4 . 
     As subsequent rows are formed on row former  4  and pushed out, as a row, onto layer table  6 , an array of articles  10  arranged in rows and, in the depicted embodiment, columns. Once the entire layer of articles  10  has been formed on layer table  6 , a transverse push bar  24  is advanced from adjacent edge  4 A of row former  4  toward apron  8 . The pusher bar advances the length of layer table  6 , pushing the array completely onto elevator doors  140  on apron  8  as illustrated in  FIG. 3 . As articles  10  are advanced, optional layer guides  6 B and  6 C, disposed spaced apart from each other along the longitudinal edges of layer table  6 , function to guide articles  10  at the edge of the array toward the center. The pusher bar  24  advances to adjacent edge  6 A (although in some configurations, pusher bar  24  may go as far as illustrated in  FIG. 3 ) and remains there as front dam  26 , and side dams  28 ,  30 , are advanced, moving articles  10  into a tighter array of the layer pattern. After in the proper relative positions, dams  26 ,  28  and  30  will retract and elevator doors  140  will open to allow the newly formed layer to drop onto the pallet  212  or a previously formed layer. 
     The location and number of stops is dependent on the pattern being formed. Stops  16 ,  18 ,  20  may be positioned, or repositioned, to any desired location aligned with a gap between adjacent rollers  14 , based on the pattern being formed. 
     Referring to  FIGS. 4 and 5 , row former  4  includes a pair of spaced apart outside frame members  32 ,  34 , which may be supported by a separate frame/support of the case palletizer  2 . Frame members  32 ,  34  carry a plurality of rotatable rollers  14  which define the upper conveying surface of row former  4 . In the embodiment depicted, at entrance end  4 B, the rollers  14  have been removed from  FIG. 2  in order to view stop  20 . The axis of rotation of the omitted rollers  14  (not shown) may be disposed at a higher level than the axis of rotation of rollers  14 , and may even decline from entrance end  4 B toward rollers  14 . Rollers  14  may be driven by any suitable drive, such as a motor driven belt (not shown) which engages rollers  14 . Such a motor could also drive the incoming conveyor which feeds former  4 . 
     Frame members  32 ,  34  also carry and support a stop subassembly  36 . Stop subassembly  36  is a support for and supports and carries a plurality of stops  16 ,  18 ,  20 , which may be repositioned to any desired configured location of stop subassembly  36 . Referring to stop  20  for example, as can be seen in  FIG. 2 , stop  20  has upper edge  20 A, which in a lowered position, lies just below the conveying surface defined by rollers  14 . Stop  16  is shown in the operable raised position, with upper edge  16 A extending above the conveying surface defined by rollers  14  a height sufficient to engage and stop articles  10 , in the depicted embodiment, about ¼ inch. 
     Stop subassembly  36  is also a support for and carries actuators  38 ,  40 , and  42 . Stop subassembly  36  includes a plurality of actuator mounting locations, illustrated as holes  45  in the depicted embodiment, respectively aligned with gaps between rollers  14 . The actuator mounting locations  45  are configured complementarily with actuators  38 ,  40 , and  42  so as to carry and provide support therefor. In the depicted embodiment, actuators  38 ,  40  and  42  are disposed through respective holes  45 , extending below central web  44 , and are secured at the top of web  44  by suitable fasteners, such as nuts  46  ( FIG. 8 ), which provide for quick installation and removal of actuators  38 ,  40  and  42 . Stop subassembly  36  and actuators  38 ,  40  and  42  are configured to permit access to the actuator from below rollers  14  in order to install or remove actuators  38 ,  40  and  42  from below. The actuator mounting locations  45  are spaced apart in a line a distance generally equal to the linear distance between the rollers  14 . Actuators  38 ,  40 , and  42   a  are configured for rapid installation and repositioning from the underside of the row former  4 . In the depicted embodiment, actuators  38 ,  40  and  42  are spring loaded single acting fluidic cylinders connected to a selectively operable fluidic source but are not limited thereto. Fluidic actuators  42  can be operated with any compressible or incompressible fluids such as but not limited, to air and hydraulic fluids respectively. Additionally, any suitable actuator may be used which provides the functionality of raising and lowering stops  16 ,  28 ,  20  such as any actuator that uses magnetism for operation. Magnetic actuators can include, but are not limited to, solenoids, and any actuator with an electric motor. 
     Referring also to  FIG. 6 , which is an exploded view of subassembly  36 , it can be seen that subassembly  36  includes spaced apart frames  48 ,  50 , each of which includes a planar upper portion  48 A,  50 A which are respectively interposed between respective pairs of two elongated guides  52  and  54 , and  56  and  58 . Guides  52  and  54 , and  56  and  58  may be made of any suitable material, such as UHMW. Each guide pair  52  and  54 , and  56  and  58 , is secured to a respective upper portion  48 A,  50 A, by a plurality of fasteners  60 , such as bolts, washers and nuts in a position that will align guide features with gaps between the rollers  14 . A plurality of spacers  62  extend between upper portions  48 A and  50 A to maintain the desired spacing and provide the desired rigidity. Spacers  62  may be an all-thread rod, with nuts and washers sandwiching the guide/upper portion/guide arrangements. It is noted that the fastener hole pattern of the embodiment depicted in  FIG. 4  includes a plurality of single holes with interspersed pairs of vertically aligned holes. The fastener hole pattern allows flexibility in the placement of spacers  62 . 
     Frames  48 ,  50  may be secured to web  44  along the respective lower edges, and connected together such as by using J hooks, such as described in U.S. Pat. No. 5,421,451, which is incorporated herein by reference. 
     Each guide pair  52  and  54 , and  56  and  58 , includes a respective plurality of grooves  52 A,  54 A (not seen in  FIG. 6 ),  56 A and  58 A (not seen in  FIG. 6 ). For reasons that will become apparent later, grooves  52 A,  54 A,  56 A, and  56 A, can be spaced linearly along the guides  52 ,  54 ,  56  and  58  at a spacing equal to the linear distance between the rollers  14 . When guide pairs  52  and  54 , are mounted to upper portion  48 A, and guide pairs  56  and  58  are mounted to upper portion  50 A, the respective grooves on either side of the upper portion  48 A and  50 A face outwards and in parallel alignment on either side of the upper portion  48 A and  50 A to form pairs of spaced apart receiving grooves in parallel alignment with one of the plurality of holes  45  in central web  44 . 
     As depicted in  FIG. 6 , each stop  16 ,  18  and  20  has respective pairs of spaced apart slots,  17 A and  17 B,  18 A and  18 B, and  21 A and  21 B. The spacing between slots  17 A,  17   b ,  18 A,  18 B,  21 A, and  21 B on each stop  16 ,  18  and  20  corresponds to the spacing between the outward facing and parallel aligned grooves  52 A,  54 A,  56 A,  58 A mounted on either side of the upper portions  48 A and  50 A. 
     Referring to stop  20  as an example, slot  21 A is received by the outward facing and parallel aligned pair of grooves  56 A,  58 A which sandwich upper portion  50 A, and slot  21 B is received by the outward facing and parallel aligned pair of grooves  52 A, 54 A which sandwich upper portion  48 A. This configuration aligns the grooves  52 A,  54 A,  56 A,  58 A with the rollers  14  to allows stops  16 ,  18 ,  20  to be slid into a pair of grooves  52 A,  54 A,  56 A,  58 A that aligns with a desired inter roller gap. This can be accomplished by aligning the stop with the desired roller gap and sliding the stop downward between the rollers  14 . Since the gaps between the rollers  14  are aligned with the grooves  52 A,  54 A,  56 A,  58 A and the holes  45 , the slots of the inserted stop  16 ,  18 , or  20  will be guided into respective grooves. Referring to  FIG. 7 , this interface is illustrated. Groove  58 A of guide  58 A aligns laterally with groove  56 A of guide  56 . Slot  21 A spans the distance between the respective bottoms of grooves  56 A and  58 A. Any suitable clearance may be used, so long as binding is avoided for the extension and retraction of stop  20 . 
     Referring to  FIG. 8 , actuator  42 , depicted as a spring loaded single acting pneumatic cylinders, includes a quick disconnect  60  that secures each actuator  38 ,  40 ,  42  to a respective stop  16 ,  18 , or  20 . Any suitable quick disconnect may be used, and in the embodiment depicted quick disconnect  60  includes bracket  63  which is received by recess  20 C of stop  20 . Bracket  63  includes upwardly pending arm  64  which receives, through a hole (not seen), retaining element  66 , illustrated as a pin. Retaining pin includes groove  66 A which receives C-clip  68  which may be snapped into and out of engagement with groove  66 A so as to retain stop  20  to actuator  42 . A flexible actuator line  65  can be attached to actuator  42  with a line connector  66 . When disconnected, line connector  65  prevents actuation of an actuator. Actuator line  65  can conduct a fluid such as air to actuate the actuator  42 . Should the actuator be magnetic, the actuator line  65  can conduct electricity for actuation thereof. Actuator line  65  is flexible and can be of sufficient length so that any one of the actuators such as actuator  42  can be moved to any one of a number of the holes  45  in central web  44  without requiring disconnection of the actuator line  65 . This simplifies and speeds up reconfiguration of the stops  16 ,  18 , and  20 . 
     Positioning or repositioning any stop, such as stop  20 , to another location is simple and efficient. Quick disconnect  60  quickly disconnects actuator  42  from stop  20 , and stop  20  is withdrawn from the top through the inter roller space with which it is aligned. Actuator  42  is disconnected from central web  44 , such as by undoing nut  46 , and withdrawn downwardly through the hole. In the embodiment depicted, central web  44  includes a plurality of spaced apart openings  47  disposed to facilitate access to the disconnect features, including quick disconnect  60  and nut  46 . Repositioning stop  20  to another location or position is the reverse procedure. If the actuators are pneumatic, the respective tube lengths may be long enough to accommodate all locations, or can be replaced as needed based on the position. 
     The foregoing description has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiment was chosen and described in order to best illustrate the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. Although only a limited number of embodiments of the invention is explained in detail, it is to be understood that the invention is not limited in its scope to the details of construction and arrangement of components set forth in the preceding description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or carried out in various ways. Also, in describing the preferred embodiment, specific terminology was used for the sake of clarity. It is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. It is intended that the scope of the invention be defined by the claims submitted herewith.