Abstract:
A conveyor diverter and method provides a device for diverting articles from a transport conveyor at increased throughput by urging a subsequent article onto the diverter before a prior article has been directed off of the diverter. The diverter raises a downstream portion of diverter surface while leaving upstream portions of the diverter surface in a lowered position, thereby permitting articles entering the diverter in a first direction to be diverted in a second direction. The diverter includes a transport conveying surface for conveying articles in the first direction and a lift assembly for raising and lowering the upstream portions and downstream portions of the diverter surface. The diverter may be configured to provide turn, cross-transfer, cross-transfer with increased throughput, and transport functions. Thus, a method is provided for achieving increased throughput and/or multiple divert functions.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    The present application claims the benefit of U.S. Provisional Application, Ser. No. 61/013,337, filed Dec. 13, 2007, which is hereby incorporated herein by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to powered conveyors and, more particularly, to diverters for powered conveyors. 
       BACKGROUND OF THE INVENTION  
       [0003]    Powered conveyors are known to include diverters for directing objects such as packages off of the conveyors. The diverters may be selectively engaged to direct only a subset of the objects conveyed on the conveyor, and may direct the objects onto another conveyor, a buffer, a collection area, or the like. 
       SUMMARY OF THE INVENTION 
       [0004]    Embodiments of the present invention provide a diverter that is suitable for transporting, cross-transferring, or diverting articles along or from a conveyor. A lift assembly is provided that is capable of lifting a downstream portion of the diverter, or both an upstream portion and the downstream portion of the diverter, in order to effect diverting or cross-transferring of articles positioned thereon. Embodiments further provide for close spacing of articles located on the transport conveyor by raising a downstream portion of the diverter to provide a transport region at the upstream portion of the diverter and a divert region at the downstream portion of the diverter. 
         [0005]    According to one aspect of the invention, a diverter is provided to divert articles from a transport conveyor. The diverter includes a transport conveying surface, a base frame, a diverter support frame, a diverter surface, a lift assembly, and a control. The transport conveying surface conveys articles in a longitudinal direction along the diverter. The diverter support frame is movably supported at the base frame. The diverter surface is supported at the diverter support frame in juxtaposition with the transport conveying surface. The diverter surface has a downstream portion with respect to movement of articles on the transport conveying surface, and laterally diverts articles traveling on the transport conveying surface off of a side of the diverter. The lift assembly is positioned at the base frame and raises the downstream portion of the diverter surface to divert an article from the transport conveying surface. The control selectively actuates the lift assembly. 
         [0006]    The diverter may be adapted to provide a cross-transfer function, a divert function, and/or a staged-drop divert function, such as by reconfiguring the lift assembly. The lift assembly may include a motor that drives one or more cams via link members or belts. The cams may be dwell cams to provide a staged-drop function during cross-transfer or a turn function, for example. The transporter members may be sheaves having continuous belts reeved thereon and arranged in spaces between the diverter surface, which may be made up of spaced rollers. 
         [0007]    Thus, a method is provided for increasing the throughput of articles across a diverter by raising only a downstream portion of the diverter. By reconfiguring a lift mechanism of the diverter, the diverter may provide increased throughput, a cross-transfer function, a staged-drop cross-transfer function, a divert or turn function, and/or a transport function. 
         [0008]    These and other objects, advantages, purposes, and features of the present invention will become apparent upon review of the following specification in conjunction with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a front elevation of a diverter in accordance with the present invention; 
           [0010]      FIG. 2  is a right side elevation of the diverter of  FIG. 1 , having portions of a base frame removed; 
           [0011]      FIG. 3  is a top plan of the diverter of  FIG. 1 , having rollers and a roller support frame removed; 
           [0012]      FIG. 4  is a front elevation of the diverter of  FIG. 1  in a divert mode; 
           [0013]      FIG. 5  is a right side elevation of the diverter of  FIG. 4 , having portions of the base frame removed; 
           [0014]      FIG. 6  is a right side elevation of the diverter in a cross-transfer mode; 
           [0015]      FIG. 7  is a right side elevation of the diverter of  FIG. 6 , having the rollers and the roller support frame removed; 
           [0016]      FIG. 8  is a right side elevation of the diverter of  FIG. 7 , having the lift assembly in a lowered position; 
           [0017]      FIG. 9  is a right side elevation of the diverter having an alternative embodiment lift assembly in a staged-drop cross-transfer mode; 
           [0018]      FIG. 10  is a right side elevation of the diverter of  FIG. 9 , having the lift assembly in a fully raised position; 
           [0019]      FIG. 11  is a right side elevation of the diverter of  FIGS. 9 and 10 , having the lift assembly in a staged-drop position; 
           [0020]      FIGS. 12A-12C  are front elevations and corresponding right side elevations of the diverter of  FIGS. 9-11 , depicting the steps of the staged-drop cross-transfer mode; 
           [0021]      FIGS. 13A-13  are front elevations and corresponding right side elevations of the diverter of  FIG. 9 , depicting the steps of a turn mode; 
           [0022]      FIG. 14  is a top plan of a transport conveyor incorporating the diverter in a left-hand divert mode; 
           [0023]      FIG. 15  is a top plan of a second transport conveyor incorporating a pair of diverters in right-hand divert modes to effect a 180 degree turn; and 
           [0024]      FIG. 16  is a top plan of a third transport conveyor incorporating the diverter in a centering mode. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0025]    Referring now to the drawings and the illustrative embodiments depicted therein, a diverter  20  for a transport conveyor  22  includes a base frame  24 , a diverter surface including a plurality of diverter members such as rollers  26  for diverting or transferring articles  28  from conveyor  22 , a plurality of transporter members such as endless drive belts  32  for transporting articles  28  along conveyor  22 , and a lift assembly  34  for selectively raising portions of rollers  26  ( FIGS. 1-3  and  14 ). A roller support frame  36  rotatably supports rollers  26  and is itself movably supported at base frame  24 . Sheaves  30  support endless drive belts  32 . A sheave support frame  38  ( FIG. 3 ) rotatably supports sheaves  30  at base frame  24 , as will be described in greater detail below. 
         [0026]    Diverter  20  has an upstream end  40  and a downstream end  42  opposite upstream end  40 . It will be understood that downstream end  42  refers to the end of diverter  20  from which articles  28  are discharged when they are not diverted by diverter  20  but instead are transported along diverter in the transport direction of conveyor  22 . Sheaves  30 , supported at sheave support frames  38 , are driven by one or more electric motors, such as motorized rollers  44  having endless drive belts  32  routed from sheaves  30  to one of motorized rollers  44  ( FIGS. 1-11 ). Optionally, and as shown, an idler roller or idler sheave  46  maintains tension and alignment of drive belts  32  at corresponding sheaves  30 . 
         [0027]    With roller support frame  36  in its fully lowered position ( FIG. 2 ), upper portions of sheaves  30  and endless drive belts  32  extend above rollers  26  and are operable to convey articles  28  from upstream end  40  to downstream end  42 . Motorized rollers  44  may be driven substantially constantly to convey articles  28  partially along diverter  20  between upstream end  40  and downstream end  42  until articles  28  are diverted off of a side of diverter  20  when downstream portions of rollers  26  are raised by lift assembly  34 . Motorized rollers  44  may be driven to convey articles  28  longitudinally along or across diverter  20  so that articles  28  are received upstream end  40  and discharged at downstream end  42  without raising rollers  26  while articles are supported at drive belts  32  of diverter  20 . Optionally, motorized rollers  44  may be controlled via a roller controller  45  to provide constant or intermittent operation of drive belts  32 . 
         [0028]    As best seen in  FIG. 4 , rollers  26  are arranged parallel to one another and may include two separately controlled sets of rollers  26   a,    26   b  controlled by a roller controller  48  mounted at upstream end  40  of diverter  20  at roller support frame  36 . Each set of rollers  26   a,    26   b  may include a motorized roller  50   a,    50   b,  each of which is controlled by roller controller  48 . Rollers  26   a,    26   b  are connected to motorized rollers  50   a,    50   b,  respectively, in a conventional manner using link belts  52  to interconnect rollers  26   a  to motorized roller  50   a  and/or to an adjacent roller  26   a,  and to interconnect rollers  26   b  to motorized roller  50   b  and/or to an adjacent roller  26   b.  Roller controller  48  is operable to drive rollers  26   a  in the same direction as rollers  26   b  ( FIGS. 14 and 15 ), to drive rollers  26   a  and rollers  26   b  oppositely and toward the center of diverter  20  ( FIG. 16 ), and to drive rollers  26   a  and rollers  26   b  oppositely away from the center of diverter  20 . 
         [0029]    In the illustrated embodiments, rollers  26  are rotatably supported at and between an upstream-end support  54  and a downstream-end support  56  of roller support frame  36  ( FIGS. 2 and 4 ). Upstream-end support  54  is connected to downstream-end support  56  by a pair of cross members  58 . Cross members  58  incorporate apertures  64  receiving locating pins  62  of base frame  24 , and rest upon support blocks  64  from which locating pins  62  extend upwardly. Support blocks  64  support cross members  58  of roller support frame  36  at the lowered position ( FIG. 2 ). Locating pins  62  guide roller support frame  36  as the upstream portion and/or downstream portion of roller support frame  36  is raised relative to base frame  24  by lift assembly  34  ( FIGS. 5 and 6 ). 
         [0030]    In the illustrated embodiments, lift assembly  34  includes a pair of transverse rods  66   a,    66   b  ( FIG. 3 ). Transverse rod  66   a  is located proximate upstream end  40  and transverse rod  66   b  is located proximate downstream end  42 . Transverse rods  66   a,    66   b  are pivotably or rotatably supported in journals  68 , which are attached to base frame  24 . A lifting cam  70   a  is positioned at an end of each rod  66   a,    66   b  and aligned underneath cross member  58  of roller support frame  36 . Similarly, a lifting cam  70   b  is positioned at an opposite end of each transverse rod  66   a,    66   b  and aligned underneath an opposite cross member (not shown). Lifting cams  70   a,    70   b  are pivotable or rotatable by rotating transverse rod  66   a,    66   b  and include lobes  72  ( FIG. 5 ) that contact cross members  58  to urge roller support frame  36  upwardly and to lower roller support frame  36  to rest at its lowered position. 
         [0031]    Lift assembly  34  includes a motor  74  for pivotably or rotatably driving transverse rods  66   a,    66   b  and lifting cams  70   a,    70   b  ( FIGS. 2 ,  3 , and  5 - 8 ). Motor  74  includes an output arm  76  that is connected to transverse rod  66   b  by a removable link  78   b  at a first end of link  78   b.  Link  78   b  is connected at a second end to a connecting link  80   b  mounted to the end of transverse rod  66   b.  Similarly, and as shown in FIG.  3  and  6 - 8 , output arm  76  of motor  74  may be connected to transverse rod  66   a  via a removable link  78   a  and a connecting link  80   a.  Thus, by selecting which of links  78   a,    78   b  is installed at lift assembly  34 , a user may select whether motor  74  is drivable to rotate either or both of transverse rods  66   a,    66   b.  Optionally, and as shown in  FIGS. 9-13B , motor  74  may include a pair of drive pulleys or sheaves  82  for driving removable belts  84   a,    84   b,  which are reeved upon input sheaves  86   a,    86   b  located at ends of transverse rods  66   a,    66   b,  respectively. In such an embodiment, an operator may select whether motor  74  is operable to rotate either or both of transverse rods  66   a,    66   b  by selectively removing or replacing removable belts  84   a,    84   b  from lift assembly  34 . 
         [0032]    Optionally, and as shown in  FIGS. 9-13B , the lifting cams at either or both of transverse rods  66   a,    66   b  may be dwell cams  88  for supporting an end of roller support frame  36  in its raised position for a longer period of time than is provided by lobes  72  of lifting cams  70   a,    70   b.  Dwell cams  88  provide a staged-drop function, as will be described in greater detail below, and may be pivoted or rotated by belts  84   a,    84   b  or by links  78   a,    78   b.    
         [0033]    Accordingly, lift assembly  34  is operable to raise roller support frame  36  via the rotation of lifting cams  70  or dwell cams  88 . For example, and with reference to  FIGS. 4 and 5 , motor  74  may be actuated to drive lifting cam  70   b  until lobe  72  is oriented substantially vertically upward, which urges the downstream portion of roller support frame  36  and rollers  26  upwardly so that the downstream portions of rollers  26  are positioned above drive belts  32 . In this configuration, articles  28  entering diverter  20  from upstream end  40  are initially carried toward downstream end  42  of diverter  20  by drive belts  32 . When a leading portion  28   a  of article  28  contacts rollers  26 , leading portion  28   a  is initially diverted in the direction of rotation of rollers  26 , such as indicated by curved arrows in  FIG. 14 . The entirety of package  28  is subsequently diverted in the direction of rotation of rollers  26 , as in  FIGS. 14 and 15 . 
         [0034]    When only removable link  78   b  (or removable belt  84   b ) is installed at lift assembly  34 , only the downstream portion of roller support frame  36  is moved to its raised position when motor  74  is actuated to rotate lifting cams  70   a,    70   b  on transverse rod  66   b  ( FIGS. 2 ,  5 ,  13 A, and  13 B). Thus, diverter  20  may be used to simultaneously change the orientation and travel direction of articles  28  that are first carried by drive belts  32 , and then by rollers  26 , as in  FIGS. 14 and 15 . 
         [0035]    With reference to  FIGS. 6-12C , removable links  78   a,    78   b  (or removable belts  84   a,    84   b ) may both be installed at lift assembly  34  to raise the entire roller support frame  36  upon actuation of motor  74  to effect a cross-transfer of articles  28  without reorienting the articles. The through-put rate of articles  28  handled by diverter  20  in the diverter&#39;s cross-transfer mode may be increased by using a staged-drop arrangement of lifting cams  70   a  at transverse rods  66   a,  and dwell cams  88  at transverse rod  66   b  ( FIGS. 9-12C ). Initially, lifting cams  70   a  and dwell cams  88  are in their lowered position ( FIGS. 9 and 12A ). Lifting cams  70   a  and dwell cams  88  are subsequently rotated approximately 90 degrees ( FIGS. 10 and 12B ) in order to raise roller support frame  36  and position rollers  26  above drive belts  32 . By rotating lifting cams  70   a  and dwell cams  88  approximately 90 degrees further ( FIGS. 11 and 12C ), lobes  72  of lifting cams  70   a  move out of contact with cross members  58  to lower the upstream portion of roller support frame  36 , while dwell cams  88  continue to support the downstream portion of roller support frame  36  in its raised position, similar to the configuration as in  FIGS. 4 and 5 . 
         [0036]    In the cross-transfer mode having a staged-drop ( FIGS. 9-12C ), articles  28  may be received at upstream end  40  of diverter  20  upon drive belts  32  while downstream articles  28  are being diverted off of diverter  20  by rollers  26 . As lifting cams  70  and dwell cams  88  continue to rotate in response to motor  74 , dwell cams  88  lower the downstream portion of roller support frame  36  before the entire roller support frame  36  is once again raised by lifting cams  70  and dwell cams  88  in order to cross-transfer the next package in substantially the same orientation at which the package arrived at upstream end  40  of diverter  20 . 
         [0037]    Optionally, a package sensor  90  may be provided at transport conveyor  22  upstream of diverter  20  ( FIG. 14 ). Package sensor  90  detects articles  28  on conveyor  22  and sends a signal to roller controller  48  to automate functions such as cross-transfer and cross-transfer with staged-drop. Roller controller  48  receives the signal and calculates the appropriate moment to actuate motor  74  to raise at least a portion of rollers  26  based upon the speed of articles  28  along conveyor  28 , the distance of sensor  90  from diverter  20 , and the time elapsed since the signal from sensor  90  was received. Thus, in cross-transfer mode, sensor  90  permits controller  48  to signal motor  74  to raise the entirety of roller support frame  36  and rollers  26  when an article is positioned fully upon diverter  20 . Similarly, in staged-drop mode, sensor  90  permits controller  48  to signal motor  74  to lower the upstream portion of frame  36  and rollers  26  when an article is approaching upstream end  40  of diverter  20 . In divert mode, sensor  90  permits controller  48  to signal motor  74  to raise the downstream portion of frame  36  and rollers  26  when an article that needs to be diverted is entering diverter  20 , and to lower the downstream portion of frame  36  and rollers  26  when an article that needs to be transported across diverter  20  without being diverted is entering diverter  20 . 
         [0038]    Accordingly, diverter  20  is operable to transport articles  28  from upstream end  40  to downstream end  42  via endless drive belts  32 , is capable of turning or reorienting articles  28  while diverting the articles to one side or the other, and is further capable of cross-transferring articles  28  off of a side of diverter  20  without reorienting the articles. By driving rollers  26   a  oppositely from rollers  26   b,  bi-direction divert, bi-direction cross-transfer, and centering functions are enabled, as will be described in greater detail below. Diverter  20  is also operable to provide a staged-drop cross-transfer that increases the throughput rate of articles  28  along transport conveyor  22  by permitting diverter  20  to receive a second article at upstream end  40  while laterally discharging a first article. Thus, the mode of diverter  20  (e.g. transport mode, divert mode, cross-transfer mode, staged-drop cross-transfer mode, bi-direction divert mode, bi-direction cross-transfer mode, centering mode, transport mode) may be selected by adding or replacing one or more of removable links  78   a,    78   b,  removable belts  84   a,    84   b,  dwell cams  88 , and lifting cams  70 , in addition to controlling motor  74  and drive belts  32  via roller controller  48 . However, it will be appreciated that the various modes of diverter  20  may be accomplished via a plurality of independently controllable actuators positioned beneath the upstream portion and downstream portion of roller support frame  36  and controlled via a function-controller, for example. In such an embodiment, a plurality of actuators, such as electrical, pneumatic, or hydraulic actuators or the like, may be positioned and controlled to raise one or both ends of rollers  26  and provide any of the desired functions of diverter  20  without need for installing or removing cams, removable links, removable belts, or the like. 
         [0039]    Diverter  20  of conveyor  22  raises discharge end  42  of rollers  26  to turn and divert articles to the left ( FIG. 14 ). By controlling the speed of rollers  26 , articles may be turned and diverted laterally up to about 90° from the longitudinal transport direction ( FIG. 15 ). Optionally, a conveyor  122  may be equipped with two or more diverters  20  to turn or cross-transfer articles  28  by more than 90°. 
         [0040]    Optionally, a conveyor  222  may be equipped with diverter  20  set to provide a centering function ( FIG. 16 ) in which roller controller  48  directs rollers  26   a  and rollers  26   b  to rotate toward the center of diverter  20 , thereby directing any off-center articles toward the center of diverter, such as by raising the entire roller support frame  36  momentarily with an article positioned thereon, before lowering lower support frame  36  so that articles  28  are carried off downstream end  42  of diverter  20  by endless drive belts  32 . Optionally, rollers  26   a  and rollers  26   b  may be driven to rotate away from the center of diverter  20  so that diverter  20  may be used to simultaneously turn, divert, or cross-transfer articles in opposite lateral directions (i.e. bi-directional turn or bi-directional cross-transfer) according to their lateral position on diverter  20 . 
         [0041]    Changes and modifications in the specifically described embodiments may be carried out without departing from the principles of the present invention, which is intended to be limited only by the scope of the appended claims, as interpreted according to the principles of patent law including the doctrine of equivalents.