Abstract:
A conveyor for unscrambling articles into single file has three lanes with the rollers of the outer lanes skewed toward the middle lane. The middle lane runs at a different speed than the outer lanes, and may have skewed rollers. The unscrambling conveyor may include several modules sequentially arranged, with a speed change within the lanes between the modules.

Description:
RELATED APPLICATION  
       [0001]     This application claims the priority of provisional patent application Ser. No. 60/786,623, titled Unscrambling Conveyor, filed on Mar. 27, 2006, the disclosure of which is incorporated herein by reference. 
     
    
     TECHNICAL FIELD  
       [0002]     The present invention relates generally to conveyors, and more particularly to conveyors used to unscramble articles into single file. The invention will be disclosed in connection with, but not necessarily limited to, a conveyor having a plurality of adjacent lanes comprised of power driven skewed rollers. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0003]     The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and, together with the general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the principles of the present invention.  
         [0004]      FIG. 1  is a top view of a conveyor constructed in accordance with the teachings of the present invention.  
         [0005]      FIG. 2  is a top view of the first section of the conveyor of  FIG. 1 .  
         [0006]      FIG. 3  is a top view of the second section of the conveyor of  FIG. 1 .  
         [0007]      FIG. 4  is a top view of the third section of the conveyor of  FIG. 1 .  
         [0008]      FIG. 5  is a perspective view of the conveyor section illustrated in  FIG. 3 .  
         [0009]      FIG. 6  is a perspective view of the conveyor frame used for the individual sections illustrated in  FIGS. 2, 3  and  4 , without the rollers, drive belt and end frame members.  
         [0010]      FIG. 7  is an enlarged, fragmentary, perspective view illustrating the path of the drive belt.  
         [0011]      FIG. 8  is an enlarged, fragmentary perspective view illustrating the mounting of a center lane roller, relative position of an outer lane roller, and a pressure sheave, taken at line  8 - 8  of  FIG. 2 .  
         [0012]      FIG. 9  is an enlarged, fragmentary top view of the illustration of  FIG. 8 .  
         [0013]      FIG. 10  is an enlarged, fragmentary, side cross-sectional view of the illustration of  FIG. 8 .  
         [0014]      FIG. 11  is an enlarged, fragmentary, cross-sectional perspective view of a pressure sheave mounted to a frame.  
         [0015]      FIG. 12  is an enlarged, fragmentary, exploded perspective view of the pressure sheave of  FIG. 11 .  
         [0016]      FIG. 13  is a perspective view of the exit end of a conveyor section, illustrating the inner frame and mounting rail.  
         [0017]      FIG. 14  illustrates rollers in their fanned orientation.  
         [0018]      FIG. 15  illustrates rollers at the entrance are fanned out.  
         [0019]      FIG. 16  illustrates a bracket bridging conveyor sections. 
     
    
       [0020]     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  
       [0021]     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 in more detail to the drawings, an embodiment of the invention will now be described.  
         [0022]     Referring to  FIG. 1 , there is illustrated unscrambling conveyor, generally indicated at  2 , constructed in accordance with some or all of the teachings of the present invention. In the embodiment depicted, conveyor  2  includes three conveyor sections,  4 ,  6  and  8 . Infeed conveyor  10  delivers articles (including by way of non-limiting example, cartons or packages) carried by its conveying surface to entrance  12  of conveyor  2 . Infeed conveyor  10  is depicted as a belt conveyor, but may be of any suitable configuration such as rollers, wheels or any other conveyor type suitable for delivering articles to entrance  12 . Infeed conveyor  12  may operate at any speed suitable to the speeds of conveyor  2 , such as, in the embodiment depicted, 70-90 feet per minute.  
         [0023]     Downstream conveyor  14  receives articles from exit  16  from conveyor  2 . Downstream conveyor  14  is depicted as power driven conveyor with a plurality of rollers  18  (for simplicity only a few of the rollers are specifically identified as  18 ). As can be seen in  FIG. 1 , the first roller  18   a  and last roller  18   b  are not skewed providing a transition from the upstream conveyor  2  and to the next conveyor (not shown) downstream of downstream conveyor  14 . Rollers  18  in between roller  18   a  and roller  18   b  may be skewed as shown, fanning out to the skewed orientation at the entrance of downstream conveyor  14  and fanning back to the non-skewed orientation at the exit of downstream conveyor  14 . The skew angle of the embodiment depicted in  FIG. 1  may be 8°, or any suitable angle. Downstream conveyor  14  may include a vertical guide of any suitable surface to assist with edge aligning articles received from conveyor  2 , such as skate wheels, moving belt or stationary surface. Although downstream conveyor  14  is depicted as a powered conveyor with skewed rollers, it may be of any suitable configuration such as tapered rollers, wheels or any other conveyor type suitable for receiving articles from exit  16 . Optionally, however, downstream conveyor  14  may not function to edge align articles. Downstream conveyor  14  may operate at any speed suitable to the speeds of conveyor  2 , such as, in the embodiment depicted, 360 feet per minute.  
         [0024]     As seen in  FIG. 1 , conveyor  2  is depicted as having three adjacent lanes  20 ,  22  and  24 , each having a plurality of longitudinally aligned rollers. As illustrated, outside lanes  20  and  24  are skewed toward the center of conveyor  2  so as to advance articles toward the center of conveyor  2 . Center lane  22  may be skewed to either side. The direction of the skew may be dictated by the configuration of the conveyor downstream of exit  16 . For example, in the embodiment depicted, the rollers in center lane  22  are skewed in the same direction as rollers  18 . Although sections  4 ,  6  and  8  are depicted as powered conveyors with skewed cylindrical rollers, they may be of any suitable configuration such as tapered rollers, wheels or any other suitable configuration and construction.  
         [0025]     In the embodiment depicted, sections  4 ,  6  and  8  are constructed modularly, with each section being the same except for orientation of the rollers at the section&#39;s entrance and of the rollers at the section&#39;s exit, although the present invention may be practiced without modular sections. Referring also to  FIG. 2 , which depicts section  4 , lanes  20  and  24  are depicted as mirror images of each other (along the longitudinal axis) with each section having a plurality of rollers  26  which form lanes  20  and  24 . In the embodiment depicted, the rollers have a diameter of about 1.9 inches and are located on about 2.12 inch centers. As will be described below, in the embodiment depicted, rollers  26  of each lane  20  and  24  are driven by a respective belt disposed under rollers  26 , guided by a respective drive and idler at either end and urged against rollers  26  by a plurality of sheaves (none of which are seen in  FIGS. 1 and 2 ). Because the drive belt falls away from the rollers adjacent entrance  28  and exit  30  of section  4 , rollers  26   a ′,  26   a ″,  26   b ″ and  26   b ″ are not directly driven by the drive belt, instead being driven by adjacent rollers in a well know manner through O-belts  34  disposed in grooves  32 . As can be seen, grooves  32  of rollers  26   a ′ and  26   b ′ are spaced differently than grooves  32  on rollers  26   a ″ and  26   b ″. This allows alignment of the grooves between adjacent rollers  26   a ′,  26   a″,  26     b ′and  26   b ″ to accommodate O-belts  34 . For clarity, only rollers  26   a ′,  26   a ″,  26   b ′ and  26   b ″ of lane  20  at entrance  28  have been numbered, although the corresponding rollers of lane  24 , and at the exit of lanes  20  and  24  are depicted in the same configuration.  
         [0026]     In the embodiment depicted, rollers  26 ,  26   a ′ and  26   a ″ are generally uniformly skewed at an angle of about 9°, having an offset of about 2.12 inches over a roller length of about 12.75 inches, although any suitable skew angle may be used. In the embodiment depicted, the illustrated skew angle will accommodate a drive belt disposed perpendicular to the axis of rotation of the rollers, the drive belt being disposed at an angle to the longitudinal axis of the conveyor sections. A greater skew angle on outside lanes  20  and  24  may allow sections  4 ,  6  and  8  to be shorter.  
         [0027]     Since entrance  28  of section  4  is entrance  12  of conveyor  2 , in the embodiment depicted, it is disposed adjacent a conveyor having an exit which is perpendicular to the longitudinal axis of conveyor  2 . Rollers  26   b ′ and  26   b ″ are fanned out at entrance  28  to transition from perpendicular (0° skew) of roller  26   b ″ to the maximum skew starting, in the embodiment depicted, with roller  26   a ′ adjacent roller  26   b ′. The fanning out maintains the gaps between the ends of rollers  26   b ″,  26   b ′ and  26   a ′ (adjacent roller  26   b ′) adjacent outer frames  36   a  and  36   b,  respectively, at acceptably small sizes. A structure may be disposed immediately upstream of entrance  12  in any gap between infeed conveyor  10  and rollers  26   b ″ and the first of rollers  38   a.    
         [0028]     Since exit  30  is disposed adjacent section  6  which, in the embodiment depicted, has skewed rollers (as described below) at its entrance, rollers  26   c ′ and  26   c ″ do not need to be fanned back to perpendicular.  
         [0029]     Center lane  22  is formed of a plurality of rollers  38  which are driven by a drive belt (not shown in  FIG. 2 ) arranged substantially the same as the drive belts driving lanes  20  and  24 . Rollers  38   a  are not directly driven by the drive belt, instead being driven by adjacent rollers in a well know manner through O-belts. In the embodiment depicted, as will be described below, the respective pulleys that drive the three drive belts for lanes  20 ,  22  and  24  are mounted on a common drive shaft (not seen in  FIGS. 1 and 2 ) powered by drive  40 , although any suitable drive arrangement may be utilized, including individual drives for each lane.  
         [0030]     In the embodiment depicted, rollers  38  are skewed toward outer frame  36   b , matching the skew direction of downstream conveyor  14  in the embodiment depicted. In the embodiment depicted, rollers  38  are skewed at an angle of about 4.2°, having an offset of about 0.5 inches across a roller length of about 6.81 inches. As will be described below, the ends of rollers  38  and  38   a  are offset from the adjacent ends of rollers  26 ,  26   a ′,  26   a ″,  26   b ′ and  26   b ″ to avoid interference with the axles.  
         [0031]     Referring to  FIG. 3 , section  6  is illustrated (with O-belts omitted for clarity). In the embodiment depicted, as mentioned above, section  6  is constructed substantially the same as section  4  except for the orientation of the rollers at entrance  42 . As seen in  FIG. 3 , entrance rollers  26   d  of lanes  20  and  24  are skewed, with outer ends  26   d ′ being respectively mounted in outer frames  36   a  and  36   b.  Due to the skew, inner ends  26   d ″ are disposed upstream beyond entrance  42 , lacking support by section  6 . Referring also to  FIG. 2 , rollers  26   d  extend beyond entrance  42 , which is adjacent exit  30 , with ends  26   d ″ being supported by section  4  at area  46 , which will be described in more detail below. This avoids needing to fan rollers out or fan rollers back at the entrance and exit of each section  4 ,  6  and  8 .  
         [0032]     Roller  38   b  is disposed generally at exit  30  of section  4  and entrance  42  of section  6 . The location of the ends of roller  38   b  are disposed at a location that, in the embodiment depicted, are supported by respective brackets  48   a  and  48   b.  One end of each bracket  48   a  and  48   b  is supported by section  4  at locations  50   a  and  50   b,  and the other end is supported by section  6 , as is described in more detail below.  
         [0033]     Referring to  FIG. 4 , section  8  is illustrated (with O-belts omitted for clarity). In the embodiment depicted, as mentioned above, section  8  is constructed substantially the same as sections  4  and  6 , except for the orientation of the rollers at exit  54 . As seen in  FIG. 4 , entrance rollers  26   d  of section  8  are disposed the same as entrance rollers  26   d  of section  6 , with inner ends  26   d ″ being respectively disposed upstream beyond entrance  52 , being supported by section  6  at area  56 . Roller  38   b  of section  8 , is disposed generally at exit  44  of section  6  and entrance  52  of section  8 , supported by brackets  48   a  and  48   b  that span sections  6  and  8  in the same manner as described above.  
         [0034]     Since exit  54  of section  8  is exit  16  of conveyor  2 , in the embodiment depicted, it is disposed adjacent a conveyor having an entrance which is perpendicular to the longitudinal axis of conveyor  2 . Rollers  26   e ′ and  26   e ″ of lane  20 , and the corresponding rollers of lane  24 , are fanned at exit  54  to transition from the maximum skew to perpendicular to the longitudinal direction. The fanning maintains the gaps between the ends of rollers  26   e ″,  26   e ′ and  26   a ′ (adjacent roller  26   e ″) adjacent inner frames  124   a  and  124   b  (see  FIG. 13 ) at acceptably small sizes.  
         [0035]     In the embodiment depicted, section  4 ,  6  and  8  are driven independently of each other, with each having respective drive units  40 ,  60 ,  62 , although any suitable drive arrangement may be used. Each section may be connected to the adjacent section in any suitable means. Each section may be assembled identical to each other, with the rollers oriented as for section  6 , and the final configuration of the rollers made during installation. In such instance, an installation kit can be utilized for each interface between sections of conveyor  2 , containing two  26   d  rollers, a  38   b  roller, brackets  48   a  and  48   b,  and any necessary fasteners and O-belts. During installation, the rollers at the entrance and exit of conveyor  2  may be fanned out as described above, using the installation kit for the interfaces between sections. In the embodiment depicted, each section is six feet long, although any length may be used. More or less than three sections may be used as suitable. It is noted that any entrance configuration of rollers that is complementary to the configuration of the upstream conveyor may be used.  
         [0036]     Each downstream section  6  and  8  are preferably, as in the embodiment depicted, operated at a higher speed than the upstream section  4  and  6  feeding it. The speeds of outer lanes  20  and  24  within each section  4 ,  6  and  8  may be, as in the embodiment depicted, the same as each other, with center lane  22  being operated at a higher speed than the outer lanes.  
         [0037]     With outer lanes  20  and  24  being skewed toward the center, articles are advanced toward the middle. When articles which are side by side reach the faster running center lane  22 , the article reaching center lane  22  first will tend to be advanced ahead of the other article. When articles reach the higher speed downstream section  6  or  8 , gaps may be introduced between articles, promoting unscrambling.  
         [0038]     In the embodiment depicted, in section  4 , the speed of outer lanes  20  and  24  is 180 feet per minute, and the speed of center lane  22  is 240 feet per minute; in section  6 , the speed of outer lanes  20  and  24  is 240 feet per minute, and the speed of center lane  22  is 320 feet per minute; in section  8 , the speed of outer lanes  20  and  24  is 300 feet per minute, and the speed of center lane  22  is 400 feet per minute. Other speeds and ratios between the sections as well between lanes may be used.  
         [0039]     Referring now to  FIG. 5 , section  6  is illustrated as a perspective view.  FIG. 6  is a perspective view of the conveyor frame used for the individual sections illustrated in  FIGS. 2, 3  and  4 , without the rollers, drive belt and end frame members. As seen in  FIG. 6 , drive shaft  66  is disposed, in the embodiment depicted, at the entrance end of the section. Drive shaft  66  has respective drive pulleys  68 ,  70  and  72  non-rotatably mounted thereto aligned with each lane  20 ,  22  and  24 , respectively. The relative diameter of drive pulleys  68 ,  70  and  72  may establish the speed ratio between each lane. Drive shaft  66  is rotatably supported by outer frames  36   a  and  36   b,  with end  66   a  extends beyond outer frame  36   b  for connection to a respective drive unit (not shown). Idler pulleys  74 ,  76  and  78  are rotatably carried by drive shaft  66 . Spaced from the entrance, horizontal pulleys  80 ,  82  and  84  disposed respectively in lanes  20 ,  22  and  24 . At the exit end, idler pulleys  86 ,  88  and  90 , and idler pulleys  92 ,  94  and  96  are disposed respectively in lanes  20 ,  22  and  24 .  
         [0040]     Spaced from the exit, horizontal pulleys  98 ,  100  and  102  are disposed respectively in lanes  20 ,  22  and  24 . Horizontal pulleys  98 ,  100  and  102  are each mounted to a respective adjustment mechanism  104 ,  106  and  108 , which respectively includes a longitudinally oriented threaded member  110 ,  112  and  114  which may be rotated to move a respective bracket  116 ,  118  and  120  to which the respective pulleys  98 ,  100  and  102  are mounted. The respective axes of rotation of pulleys  98 ,  100  and  102  may be adjusted longitudinally independent of each other.  
         [0041]     Also seen in  FIG. 6  are a plurality of spaced apart rotatable sheaves  122  mounted within each lane  20 ,  22  and  24 , along the inside faces of outer frames  36   a  and  36   b,  and from the inner surface of inner frame  124   b.  Respective sheaves  126 ,  128  and  130  are disposed in lanes  20 ,  22  and  24 , respectively, generally in the middle between the ends.  
         [0042]     The pulleys and sheaves define the path of the drive belts (not shown in  FIG. 6 ). Referring only to outside lane  24 , which exemplifies the drive belt arrangement for lanes  20  and  22 , drive pulley  72  is aligned with pressure sheaves  122  carried by outer frame  36   b.  Pulleys  96  and  90  are aligned with horizontal pulley  102 . Sheave  130  and pulley  78  are generally aligned with pulley  90 . Pulley  78  and drive pulley  72  are aligned with horizontal pulley  84 .  
         [0043]     Referring to  FIG. 7 , which illustrates an enlarged, fragmentary, perspective view illustrating one end of the path of drive belt  132 , which in the embodiment depicted, is shown as a V-belt, although any suitable shape may be used. Side  132   a  of belt  132  travels in the direction indicated. The end configuration of endless drive belt  132  illustrated in  FIG. 7  is identical to the opposite end of belt  132 , except that pulley  96  is replaced by drive pulley  72 . Tension and slack of belt  132  may be adjusted by adjustment mechanism  108 , moving pulley  102  longitudinally in the desired direction. Portion  138   a  is supported by sheaves  122  near outer frame  36   b,  with sheaves  122  urging portion  138   a  into driving engagement with rollers  26 . At the entrance end, portion  138   a  is driven by drive pulley  72 . From there, belt  132  extends around pulley  84  and idler pulley  78 . Now portion  132   b,  belt  132  returns to pulley  90 , supported by pulley  130 . With this configuration, belt  132  avoids having any frame cross members  134  extend through the center of belt  132 , making installation easier.  
         [0044]     Referring to  FIG. 8 , there is shown an enlarged, fragmentary perspective view illustrating the mounting of center lane roller  38 , relative position of an outer lane roller, and a pressure sheave, taken at line  8 - 8  of  FIG. 2 . It is noted, in  FIGS. 8, 9  and  10 , that although the ends of the illustrated components, such as rollers  26  and  38  and inner frame  124   b,  are not illustrated utilizing broken lines, the view is of a section taken at line  8 - 8  of  FIG. 2 . Rollers  26  and  38  have axles extending from either end, which may be solid or a stub axle extending there from, which may be of any suitable shape, such as hexagonal which functions to prevent rotation of the axle in its support. As seen in  FIG. 8 , inner frame  124   b  carries mounting rail  136   b,  which extends the length of the conveyor section, either as a single, unitary member as in the embodiment depicted, or as multiple members. Mounting rail  136   b  includes a plurality of spaced apart roller support openings  138  shaped complementarily to receive the axle support of rollers  38  to provide support to one end thereof. Although not visible in  FIG. 8 , inner frame  124   b  includes a plurality of spaced apart roller support openings to support the inner end of rollers  26 .  
         [0045]     Referring also to  FIGS. 9 and 10 , a plurality of spacers  140  spaced apart longitudinally along inner frame  124   b  maintain mounting rail  136   b  in a lateral spaced apart relation to inner frame  124   b.  Mounting rail  136   b  and spacers  140  are secured in place by threaded fasteners  142 , such as carriage bolts, and nuts  142   a  at spaced locations. Mounting rail  136   b  includes longitudinally extending openings  144  through which fasteners  142  extend into respective openings in inner frame  124   b.  The shape of openings  144  permit longitudinal adjustment of rollers  38 . In the embodiment depicted, when mounting rail  136   a  (not shown in  FIGS. 8-10 ) is mounted to inner frame  124   a  in the same longitudinally adjustable manner, the amount and direction of skew of center lane  22  may be adjusted by the relative positioning of mounting rails  136   a  and  136   b.    
         [0046]     As seen in  FIGS. 8-10 , the roller axles of the inner end of rollers  26  and of rollers  38  are held in place by cap  146  and spacer  148 . The upper surface of cap  146  is slightly lower than the conveying surface defined by the upper tangent edge of rollers  26  and  38 . The entrance and exit ends of cap  146  are tapered to avoid presenting an edge that might catch articles. Cap  146 , made of any suitable material, such as metal, may be secured in place by threaded fasteners  150  which engage spacers  140 . Spacer  140  and  148  may be made of any suitable material, such as HDPE. (It is noted that, in the embodiment depicted, the outside axles of rollers  26  on either outside lane  20  and  24  extend into complementarily shaped openings formed in outer frames  36   a  and  36   b,  needing no cap to hold them in place.)  
         [0047]     Referring particularly to  FIG. 10 , pressure sheave  122  is illustrated urging drive belt  132   a  against the lower surface of roller  38 . Each sheave  122  of each lane  20 ,  22  and  24 , is aligned in the gap between adjacent pairs of rollers  26  or  38 , leaving alternating gaps between the rollers empty. Sheave  122  may be mounted in any suitable manner. Referring also to  FIGS. 11 and 12 , which illustrates a mounting configuration for sheave  122 , sheave  122  is rotatably mounted to mounting base  152  through bearing  122   a,  which may be secured to frame member,  36  or  124 , through carriage bolt  154 . Mounting base  152  includes boss  152   a,  which in the embodiment depicted, is generally rectangular or square in shape, which is shaped complementary to opening  158  formed in frame member  36  or  124 . Opening  158  extends vertically to allow vertical adjustment of sheave  122  to adjust the pressure of drive belt  132  against the rollers. The shape of boss  152   a  allows vertical movement of boss  152   a  within opening  158 , but not rotation. Thus, the interface between this end of mounting base  152  and the frame prevents relative rotation while allowing vertical adjustment. The other end of mounting base  152  includes an internal configuration that is shaped complementarily to the rotation resistant configuration of the head of fastener  154 , in the embodiment depicted, the square shape of the carriage bolt. This configuration resists relative rotation between fastener  154  and mounting base  152 . The resistance to relative rotation of the interface between fastener  154  and mounting base  152  at the distal end of mounting base  152 , combined with the resistance to relative rotation of mounting base  152  to frame  36  or  124  allows sheave to be adjusted and secured through nut  154   a.    
         [0048]      FIG. 13  illustrates openings  156  in inner frame  124   b,  for receiving the inner axle ends of outer rollers  26 . Openings  156  are generally evenly spaced, with opening  156   b  disposed in-between spaced apart openings  156 . Opening  156   b  is located to receive inner end axle of roller  26   e ″ when the rollers at the exit are fanned back.  FIG. 14  illustrates roller  26   e ″ and adjacent rollers in their fanned orientation.  
         [0049]      FIG. 15  illustrates openings  160  in outer frame  36 , for receiving the outer ends of outer rollers  26 . Openings  156  are evenly spaced, with opening  160   a  (not seen in  FIG. 15 ) disposed in between spaced apart openings  160 . Opening  160   a  is located to receive outer end axle of roller  26   b ′ when the rollers at the entrance are fanned out. As can be seen, O-belts may be located at the inner end of rollers  26 .  
         [0050]      FIG. 16  illustrates bracket  48   a  bridging sections  4  and  6 .  
         [0051]     The foregoing description of a preferred embodiment of the invention 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. It is intended that the scope of the invention be defined by the claims submitted herewith.