Patent Publication Number: US-2022227585-A1

Title: Multi-Directional Spiral Conveyor System

Description:
PRIORITY 
     This application claims the benefit of U.S. Pat. App. No. 63/139,395, entitled “Multi-Directional Spiral Conveyor System,” filed Jan. 20, 2021, the disclosure of which is incorporated by reference herein. 
    
    
     BACKGROUND 
     The present disclosure relates generally to conveyors for transporting articles or packages, and is more particularly directed to spiral conveyors that convey articles or packages from one level (e.g. a first floor of a building) to another level (e.g., a second floor of the building). A spiral conveyor system typically comprises a generally vertical support extending between the levels (e.g., between the first and second floors of the building). A spiral conveyor is then typically wrapped about the support in a spiral configuration to define a conveying surface, for carrying the articles or packages thereon between the levels. Described herein are versions of multi-directional and/or multi-lane spiral conveyor systems to selectively convey articles or packages between levels. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings illustrate embodiments which serve to explain the principles of the present innovation. 
         FIG. 1  is an isometric view of a portion of a first exemplary multi-directional spiral conveyor system. 
         FIG. 2  is a front view of the portion of the spiral conveyor system of  FIG. 1 . 
         FIG. 3  is a top plan view of the portion of the spiral conveyor system of  FIG. 1 . 
         FIG. 4  is a front view of a support of the spiral conveyor system of  FIG. 1 . 
         FIG. 5  is a top plan view of the support of  FIG. 4 . 
         FIG. 6  is a front view of a support section module of the support of  FIG. 4 . 
         FIG. 7  is a top plan view of the support section module of  FIG. 6 . 
         FIG. 8  is an enlarged partial perspective view of the encircled area of the support section module of  FIG. 7  shown by circle  8  of  FIG. 7 . 
         FIG. 9  is an isometric view of a portion of a vertical support of the support section module of  FIG. 6 . 
         FIG. 10  is a front view of the portion of the vertical support of  FIG. 9 . 
         FIG. 11  is an isometric view of a horizontal support of the support section module of  FIG. 6 . 
         FIG. 12  is an exploded isometric view of an arm assembly of the support of  FIG. 4 . 
         FIG. 13  is a side elevational view of the arm assembly of  FIG. 12 . 
         FIG. 14  is an end view of the arm assembly of  FIG. 12 . 
         FIG. 15  is an enlarged partial front view of the arm assembly and the support of 
         FIG. 4  shown by rectangle  15  of  FIG. 4 . 
         FIG. 16  is an enlarged partial end view of the arm assembly of the support of  FIG. 4  shown by rectangle  16  of  FIG. 4 . 
         FIG. 17  is an enlarged partial top plan view of the arm assembly of the support of 
         FIG. 4  shown by rectangle  17  of  FIG. 5 . 
         FIG. 18  is an enlarged partial top isometric view of a spiral conveyor of the portion of the spiral conveyor system of  FIG. 1  coupled with the arm assembly. 
         FIG. 19  is an enlarged partial bottom isometric view of the spiral conveyor of 
         FIG. 18  with portions of the spiral conveyor shown in with a fainter line formatting for illustrative purposes. 
         FIG. 20  is an enlarged partial bottom plan view of the portion of the spiral conveyor of  FIG. 1 . 
         FIG. 21  is an enlarged partial side elevational view of the spiral conveyor of  FIG. 20 , with a portion of a side wall removed for illustrative purposes. 
         FIG. 22  is a top plan view of the portion of the spiral conveyor system of  FIG. 1 , showing tangential inputs of the first and second conveying surfaces and tangential outputs of the first and second conveying surfaces. 
         FIG. 23A  is an isometric view of a portion of the portion of the spiral conveyor system of  FIG. 1 , showing a first conveying surface and a second conveying surface of the spiral conveyor system configured in a multi-lane configuration in a declining direction. 
         FIG. 23B  is an isometric view of the portion of the spiral conveyor system of  FIG. 23A , showing the first conveying surface and the second conveying surface of the spiral conveyor system configured in a multi-lane configuration in an inclining direction. 
         FIG. 23C  is an isometric view of the portion of the spiral conveyor system of  FIG. 23A , showing the first conveying surface and the second conveying surface of the spiral conveyor system configured in a multi-directional configuration with the first conveying system moving in the declining direction and the second conveying system moving in the inclining direction. 
         FIG. 23D  is an isometric view of the portion of the spiral conveyor system of  FIG. 23A , showing the first conveying surface and the second conveying surface of the spiral conveyor system configured in a multi-directional configuration with the first conveying system moving in the inclining direction and the second conveying system moving in the declining direction. 
         FIG. 24  is a partial isometric view of a conveyor system incorporating a plurality of the spiral conveyor systems of  FIG. 1 . 
         FIG. 25  is an elevational side view of a portion of a second exemplary multi-directional spiral conveyor system. 
         FIG. 26  is a top plan view of the portion of the spiral conveyor system of  FIG. 25 . 
         FIG. 27  is an isometric view of a portion of a third exemplary multi-directional spiral conveyor system. 
         FIG. 28  is a top plan view of a portion of the spiral conveyor system of  FIG. 27  showing radial or perpendicular inputs and outputs on an inclining spiral configuration. 
     
    
    
     The drawings are not intended to be limiting in any way, and it is contemplated that various embodiments of the innovation may be carried out in a variety of other ways, including those not necessarily depicted in the drawings. The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present innovation, and together with the description serve to explain the principles of the innovation; it being understood, however, that this innovation is not limited to the precise arrangements shown. 
     DETAILED DESCRIPTION 
     The following description of certain examples of the innovation should not be used to limit the scope of the present innovation. Other examples, features, aspects, embodiments, and advantages of the innovation will become apparent to those skilled in the art from the following description, which is by way of illustration, one of the best modes contemplated for carrying out the innovation. As will be realized, the innovation is capable of other different and obvious aspects, all without departing from the innovation. Accordingly, the drawings and descriptions should be regarded as illustrative in nature and not restrictive. 
     It is further understood that any one or more of the teachings, expressions, embodiments, examples, etc. described herein may be combined with any one or more of the other teachings, expressions, embodiments, examples, etc. that are described herein. The following described teachings, expressions, embodiments, examples, etc. should therefore not be viewed in isolation relative to each other. Various suitable ways in which the teachings herein may be combined will be readily apparent to those of ordinary skill in the art in view of the teachings herein. Such modifications and variations are intended to be included within the scope of the claims. 
     For clarity of disclosure, spatial terms such as “vertical,” “vertically,” “horizontal,” “horizontally,” “upward,” “upwardly,” “downward,” “downwardly,” “rear,” “side,” “top,” “bottom,” “inwardly,” “outwardly,” “outward,” “inclining,” “declining,” “lower,” “higher,” and “upper” also are used herein for reference to relative positions and directions. Such terms are used below with reference to views as illustrated for clarity and are not intended to limit the innovation described herein. 
     Furthermore, the terms “about,” “approximately,” and the like as used herein in connection with any numerical values or ranges of values are intended to encompass the exact value(s) referenced as well as a suitable tolerance that enables the referenced feature or combination of features to function for the intended purpose described herein. 
     The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any implementation described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other implementations. 
     A spiral conveyor system is configured to transport a plurality of articles thereon between at least one first level and at least one second level having a different elevation than that of the at least one first level. The spiral conveyor system comprises a support extending generally vertically from a position at or near the at least one first level to a position at or near the at least one second level and a conveyor assembly having more than one spiral conveyor coupled with the support. Each spiral conveyor defines a conveying surface configured to transport the plurality of articles thereon, wherein each spiral conveyor extends around the support in a generally helical configuration such that each spiral conveyor is interleaved in an alternating configuration with the other spiral conveyors about a longitudinal axis of the support from a respective first level to a respective second level. Each spiral conveyor may have a circular shape, an elliptical shape, or some other mix of straight and/or curved segmented configurations. In some versions, each spiral conveyor may have a substantially constant radius along the longitudinal axis. In other versions, each spiral conveyor may have a variable radius along the longitudinal axis. In addition, or alternatively, each spiral conveyor may have a substantially constant pitch measured parallel to the longitudinal axis. In other versions, each spiral conveyor may have a variable pitch measured parallel to the longitudinal axis. 
     Each conveying surface is configured to selectively move in an inclining direction and/or a declining direction between the respective levels. The spiral conveyor system is thereby configured to selectively operate in a multi-directional configuration and/or a multi-lane configuration. For instance, a first conveying surface is configured to transport a plurality of articles in an opposing inclining or declining direction from a second conveying surface when the spiral conveyor system is in the multi-directional configuration. Alternatively, the first conveying surface is configured to transport a plurality of articles in the same inclining or declining direction as the second conveying surface when the spiral conveyor system is in the multi-lane configuration. 
     Accordingly, the increased amount of the conveying surface area of the spiral conveyor system in the helical configuration provides an increased flow capability and/or functional capacity relative to a typical single lane spiral conveyor system. The additional conveying surfaces of the spiral conveyor system may also allow the spiral conveyor system to transport a plurality of articles between levels more efficiently while conserving, minimizing, and/or optimizing the amount of floor space occupied by the spiral conveyor system. 
     I. A First Exemplary Multi-Directional Spiral Conveyor System 
       FIGS. 1-3  show a first exemplary multi-directional spiral conveyor system  10  configured to transport a plurality of articles  8  conveyed thereon between one of first levels  4  or  5  and a respective second level  6  or  7  having a different elevation than the respective first level  4  or  5 . Spiral conveyor system  10  comprises a support  20  extending generally vertically between each first level  4 ,  5  and each respective second level  6 ,  7 , and a conveyor assembly  30  coupled with support  20 . More particularly, support  20  extends from a position at or below each first level  4 ,  5  to a position at or above each second level  6 ,  7 . In the illustrated version, support  20  is designed such that the spiral conveyor portion revolves about a single longitudinal axis A. Conveyor assembly  30  comprises a first spiral conveyor  32  defining a first conveying surface  33  configured to transport a plurality of articles  8  thereon, and a second spiral conveyor  34  defining a second conveying surface  35  also configured to transport a plurality of articles  8  thereon. In the illustrated version, second conveying surface  35  is independently operable from first conveying surface  33 . First and second spiral conveyors  32 ,  34  are positioned about support  20  in a double helical configuration such that first and second spiral conveyors  32 ,  34  are interleaved in an alternating configuration about longitudinal axis A of support  20 . In the illustrated version, first spiral conveyor  32  extends from an output  37  at first level  5  to an input  36  at second level  7 , and second spiral conveyor  34  extends from an output  39  at first level  4  to an input  38  at second level  6 . More particularly, first level  5  of first spiral conveyor  32  is positioned at least slightly above first level  4  of second spiral conveyor  34 , and second level  7  of first spiral conveyor  32  is positioned at least slightly above second level  6  of second spiral conveyor  34 , such that first spiral conveyor  32  is positioned above second spiral conveyor  34 . In some other versions, first levels  4 ,  5  may be positioned at a substantially same height as each other (e.g., by extending first spiral conveyor  32  further downwardly along its spiral path) and/or second levels  6 ,  7  may be positioned at a substantially same height as each other (e.g., by extending second spiral conveyor  34  further upwardly along its spiral path). In other versions, first level  5  of first spiral conveyor  32  may be positioned at least slightly below first level  4  of second spiral conveyor  34 , and second level  7  of first spiral conveyor  32  may be positioned at least slightly below second level  6  of second spiral conveyor  34 , such that first spiral conveyor  32  may be positioned below second spiral conveyor  34 . While two levels  4 ,  5 ,  6 ,  7  are shown and described for each conveyor  32 ,  34 , it should be understood that more levels may be employed for each conveyor  32 ,  34 . For example, one or both conveyors  32 ,  34  may include one or more additional inputs and/or outputs at levels between the respective first and second levels  4 ,  5 ,  6 ,  7 . It may also be understood that more than two conveyors  32 ,  34  may be employed in a triple, quadruple, or other configuration. 
     Each of first and second conveying surfaces  33 ,  35  of first and second spiral conveyors  32 ,  34  are configured to selectively move in an inclining direction to transport a plurality of articles  8  upward and/or a declining direction to transport a plurality of articles  8  downward. Accordingly, spiral conveyor system  10  is configured to operate in a selectable multi-directional and/or multi-lane configuration. For instance, first conveying surface  33  is configured to transport a plurality of articles  8  in an opposing direction from second conveying surface  35  in the selected one of the inclining and declining directions when spiral conveyor system  10  is in the multi-directional configuration. First conveying surface  33  is configured to transport a plurality of articles  8  in the same direction as second conveying surface  35  in the selected one of the inclining and declining directions when spiral conveyor system  10  is in the multi-lane configuration. 
     A. An Exemplary Support 
     Support  20  of spiral conveyor system  10  is shown in more detail in  FIGS. 4-7 . 
     Support  20  comprises one or more support section modules  28  vertically aligned and coupled together at intersection  21  to form a desired height of support  20 . While the illustrated version shows two support section modules  28 , any other suitable number can be used. While this version shows a spiral conveyor having a circular shape, support  20  can be of any shape or configuration such that it supports the spiral conveyor system having a circular shape or any other suitable shape (e.g., elliptical, etc.). Referring to  FIGS. 6-7 , each support section module  28  comprises a plurality of vertical supports  22  and a plurality of horizontal supports  24  positioned between vertical supports  22 . Vertical supports  22  extend generally vertically and are spaced apart from one another by horizontal supports  24 . In the illustrated version, four vertical supports  22  are shown such that vertical supports  22  are equidistantly spaced apart about 90° relative to each other, though any other suitable number and/or spacing can be used. In some versions, support  20  may include a single, centrally positioned, vertical column support. Accordingly, support section module  28  of the illustrated version has a generally square cross-sectional profile, as shown in  FIG. 7 , but any other suitable profile can be used (e.g., triangular, pentagonal, hexagonal, octagonal, etc.) depending on the number of vertical supports  22  used. Horizontal supports  24  extend generally horizontally and are spaced apart from one another longitudinally along vertical supports  22 . In the illustrated version, horizontal supports  24  are aligned in rows  23  between each vertical support  22  at a lower portion, a central portion, and an upper portion of each vertical support  22 , as shown in  FIG. 6 , but other suitable configurations can be used. 
     As shown in  FIGS. 9-10 , each vertical support  22  comprises a web  60 , a pair of side walls  62  extending from opposite end portions of web  60 , and a pair of flanges  64  extending inwardly from each side wall  62 . Accordingly, vertical support  22  has a generally C-shaped profile, though other suitable configurations can be used. Each opposite end portion of web  60  of vertical support  22  includes a plurality of openings  66  extending through web  60 . In the illustrated version, openings  66  are aligned generally longitudinally along each opposite end portion of web  60  adjacent to side walls  62 . Each side wall  62  further includes a plurality of openings  68  extending through each side wall  62 . In the illustrated version, openings  68  are aligned generally longitudinally along each side wall  62 . 
     Referring to  FIG. 11 , each horizontal support  24  comprises a rear wall  70 , a pair of side walls  72  extending outwardly from each opposite end portion of rear wall  70 , a top wall  74  extending outwardly from a top portion of rear wall  70  between side walls  72 , and a bottom wall  76  extending outwardly from a bottom portion of rear wall  70  between side walls  72 . Each end portion of top and bottom walls  74 ,  76  of horizontal support  24  are tapered such that horizontal support  24  is longer in the front open portion of horizontal support  24  than at the closed rear wall  70  portion. In the illustrated version, the end portions of top and bottom walls  74 ,  76  extend outward at about 45° relative to rear wall  70 , though other suitable dimensions can be used. For instance, the angle of top and bottom walls  74 ,  76  may change depending on the number of vertical supports  22  used to form a complementary angle with vertical supports  22 . Top wall  74  of horizontal support  24  includes a plurality of openings  75  extending through top wall  74  and generally aligned longitudinally along a central portion of top wall  74 . Bottom wall  76  also includes a plurality of openings  77  extending through bottom wall  76  and aligned generally longitudinally along a central portion of bottom wall  76 . Each side wall  72  includes a plurality of openings  73  extending through side walls  72 . 
     Referring back to  FIGS. 7-8 , side walls  62  of vertical support  22  are selectively couplable with side walls  72  of horizontal support  24 . For instance, a side wall  72  of horizontal support  24  is aligned with a side wall  62  of vertical support  22  such that openings  73  of horizontal support  24  are aligned with openings  68  of vertical support  22 . A fastener  25  (e.g., a bolt, a screw, a rivet, etc.) is then positioned through openings  68 ,  73  of vertical and horizontal supports  22 ,  24  to couple horizontal support  24  with vertical support  22 . Additionally or alternatively, supports  22 ,  24  can be coupled by welding or any other suitable bonding technique (e.g., glue, clamps, etc.). Because each side wall  62  of vertical support  22  includes a plurality of openings  68 , horizontal support  24  is configured to be selectively coupled to vertical support  22  at a desired height. Accordingly, the position of horizontal support  24  can also be adjusted along the length of vertical support  22 . In the illustrated version, horizontal supports  24  are coupled with vertical supports  22  such that horizontal supports  24  are aligned with each other in a plurality of rows  23 . In some other versions, horizontal supports  24  are offset relative to each other. 
     Referring back to  FIG. 4 , support section modules  28  of support  20  can be selectively coupled together by aligning bottom walls  76  of horizontal supports  24  of one support section module  28  with top walls  74  of horizontal supports  24  of another support section module  28 , as shown at intersection  21 . This may align openings  75 ,  77  of horizontal supports  24  such that fasteners (e.g., screws, bolts, rivets, etc.), may be inserted through openings  75 ,  77  to secure support section modules  28  together. Additionally or alternatively, support section modules  28  can be coupled by welding or any other suitable bonding technique (e.g., glue, clamps, etc.). A base support  26  can then be coupled to one or more vertical supports  22  at a bottom portion of support section module  28  such that base support  26  provides additional support by anchoring support  20  to a floor surface  2 . 
     Support  20  further comprises a plurality of arm assemblies  90  extending outward from each vertical support  22  in a cantilever configuration. Arm assemblies  90  are thereby configured to support conveyor assembly  30 . As best seen in  FIGS. 4-5 , arm assemblies  90  are longitudinally and rotationally offset relative to each other about support  20 . For instance, a first arm assembly  90   a  is positioned on a first vertical support  22 , and an adjacent second arm assembly  90   b  is positioned clockwise or counterclockwise on the next adjacent vertical support  22  at an angle a such that the adjacent second arm assembly  90   b  is rotationally offset from the first arm assembly  90   a  about a longitudinal axis of support  20 . In the illustrated version, adjacent arm assemblies  90   a,    90   b  are rotationally offset about 90 degrees relative to each other, but any other suitable angles can be used. Additionally or alternatively, adjacent second arm assembly  90   b  is longitudinally offset relative to first arm assembly  90   a  along support  20  such that adjacent second arm assembly  90   b  is spaced a distance d relative to first arm assembly  90   a.  Adjacent arm assemblies  90   a,    90   b  may be longitudinally offset relative to each other from about 6 inches to about 12 inches, such as about 9 inches, though other suitable dimensions can be used. This may allow for about 24 inches to about 48 inches, such as about 36 inches, of elevation change for one revolution about each spiral conveyor  32 ,  34 . Still other suitable dimensions can be used. This may allow each spiral conveyor  32 ,  34  of conveyor assembly  30  to form a helical configuration about support  20 . 
       FIGS. 12-14  show arm assembly  90  in more detail. Each arm assembly  90  comprises an arm  94 , an arm support  92 , and a pair of conveyor supports  96 . Arm  94  includes a body  120  extending between a first end  122  and a second end  124 . First end  122  is coupled with arm support  92  such that body  120  extends outwardly from arm support  92  to a free, second end  124 , which may be covered by a cap  98 . Arm support  92  includes an upright portion  100  and a lateral portion  102  extending outward from upright portion  100  to form a generally L-shaped bracket, though other suitable configurations may be used. Accordingly, first end  122  of arm  94  can be positioned against upright portion  100  and lateral portion  102  of arm support  92 . In some versions, arm  94  can be coupled with arm support  92  such as by welding and/or fasteners (e.g., a bolt, a screw, a rivet, etc.). Upright portion  100  of arm support  92  further includes a plurality of openings  104  extending through upright portion  100 . 
     Each conveyor support  96  comprises an upright portion  110  and a lateral portion  112  extending outward from upright portion  110  to form a generally L-shaped bracket, though other suitable configurations may be used. Each portion  110 ,  112  includes openings  114 ,  116  extending through each corresponding portion  110 ,  112 . Conveyor support  96  further includes brackets  118  having a generally U-shaped configuration. Accordingly, lateral portions  112  of each conveyor support  96  can be positioned on a top surface of arm  94  and each bracket  118  can be positioned underneath arm  94  and inserted through openings  116  of conveyor support  96  to maintain the position of conveyor support  96  relative to arm  94 . 
     Referring to  FIGS. 15-17 , each arm assembly  90  can be selectively coupled to support  20  at a desired height, which can be adjusted. For instance, upright portion  100  of arm support  92  is positioned against web  60  of a vertical support  22  to align openings  104  of arm support  92  with openings  66  of vertical support  22  at a desired height. In the illustrated version, openings  104  of arm support  92  are configured as slots having a length along upright portion  100  of arm support  92 . Accordingly, the position of upright portion  100  may be adjusted along each slot  104  relative to an opening  66  of web  60  to provide further adjustment of arm support  92  along vertical support  22  between openings  66 . Fasteners may then be inserted through openings  66 ,  104  to couple arm support  92  with vertical support  22 . Additionally or alternatively, arm support  92  may be welded to vertical support  22 . Conveyor assembly  30  may then be coupled with conveyor supports  96 , as will be discussed in more detail below. Still other suitable configurations for support  20  will be apparent to one with ordinary skill in the art in view of the teachings herein. 
     B. An Exemplary Conveyor Assembly 
     Referring back to  FIGS. 1-3 , conveyor assembly  30  comprises a first spiral conveyor  32  and a second spiral conveyor  34 . Each conveyor  32 ,  34  comprises a pair of side walls  44  and a plurality of rollers  42  extending between side walls  44  that are rotatable relative to side walls  44 . The plurality of rollers  42  of first spiral conveyor  32  define a first conveying surface  33  extending along first spiral conveyor  32  configured to transport articles  8  thereon. The plurality of rollers  42  of second spiral conveyor  34  define a second conveying surface  35  extending along second spiral conveyor  34  that is independently operable from first conveying surface  33 , which is also configured to transport articles  8  thereon. 
     Side walls  44  of each conveyor  32 ,  34  are coupled with conveyor supports  96  of support  20 , as shown in  FIGS. 18-19 . For instance, an interior surface of each side wall  44  may be aligned with an exterior surface of each upright portion  110  of a corresponding conveyor support  96 . A bottom surface of each side wall  44  may rest on arm  94  to support side walls  44 . Each side wall  44  may further include openings that align with openings  114  of conveyor support  96  such that fasteners may be inserted through openings  114  to secure side walls  44  with conveyor supports  96 . Additionally or alternatively, side walls  44  may be welded with conveyor supports  96 . 
     As shown in  FIGS. 18-19 , each roller  42  is tapered from a first end  41  to a second end  43  such that roller  42  narrows from first end  41  to second end  43 . Accordingly, rollers  42  widen as rollers  42  extend outwardly from support  20 . This may accommodate the spiral configuration of first and second spiral conveyors  32 ,  34  to provide a substantially continuous conveying surface  33 ,  35 . Rollers  42  further include a pair of grooves  45 ,  47  for receiving an O-band  46  therein. In the illustrated version, grooves  45 ,  47  are positioned near second end  43  at a narrower portion of roller  42 . Rollers  42  of the illustrated version are typically powered in zones by using interconnecting O-bands  46  in conjunction with a single electric or electromagnetic motor  48 , which rests below the driven rollers  42 . Motor  48  may comprise an external rotor gearless motor as shown in U.S. Pat. No. 10,093,487, for example. Motor(s)  48  can be controlled such that the drive rotation can spin in the appropriate product flow direction, such as the inclining and/or declining directions. For instance, as shown in  FIGS. 20-21 , an O-band  46  is coupled with motor  48  and at least one roller  42 . In some versions, an O-band  46  is coupled with two rollers  42 . A plurality of O-bands  46  are then interconnected between rollers  42 , within grooves  45 ,  47 , to operationally couple the plurality of rollers  42  with motor  48 . Accordingly, when motor  48  is actuated, motor  48  rotates to thereby rotate the plurality of rollers  42  via O-bands  46 . Motor  48  is configured to rotate rollers  42  in both an inclining and declining direction. In some versions, motorized drive roller (MDR) conveyors may define portions or all of conveying surfaces  33  and  34 . 
     Referring back to  FIGS. 1-3 , each of first and second spiral conveyors  32 ,  34  are generally curved in a spiral such that first and second spiral conveyors  32 ,  34  are positioned in a helical configuration about support  20 . In the illustrated version, first and second spiral conveyors  32 ,  34  are concentrically aligned with each other and are interleaved in an alternating configuration to form a double helical configuration about longitudinal axis A of support  20 . First and second spiral conveyors  32 ,  34  are shown having a circular profile, as shown in  FIG. 3 , but any other suitable profile shape can be used (e.g., oval, elliptical, square, rectangular, etc.). As best shown in  FIG. 2 , first spiral conveyor  32  defines a first rise R 1  that corresponds to the change in elevation of one revolution of first spiral conveyor  32  about support  20 . In the illustrated version, first rise R 1  is from about 24 inches to about 48 inches, such as about 36 inches, though other suitable dimensions can be used. Second spiral conveyor  34  defines a second rise R 2  that corresponds to the change in elevation of one revolution of second spiral conveyor  34  about support  20 . Second rise R 2  can be the same or different than first rise In the illustrated version, second rise R 2  is substantially equal to first rise Second rise R 2  can be from about 24 inches to about 48 inches, such as about 36 inches, though other suitable dimensions can be used. 
     In some versions, rise R 1 , R 2  of first and second spiral conveyors  32 ,  34  can be increased and/or decreased. As rise R 1 , R 2  increases and/or decreases, an inner radius R of first and second spiral conveyors  32 ,  34  correspondingly increases and/or decreases to substantially maintain a desired angle of inclination. For instance, a rise R 1 , R 2  of about 36 inches may correspond to an inner radius R of first and second spiral conveyors  32 ,  34  of about 32½ inches. An increase and/or decrease in rise R 1 , R 2  of first and second spiral conveyors  32 ,  34  of about 12 inches may correspond to an increase and/or decrease in inner radius R of first and second spiral conveyors  32 ,  34  of about 15 inches, though other suitable dimensions can be used. 
     Because of the spiral configuration of first and second spiral conveyors  32 ,  34 , each conveying surface  33 ,  35  can be configured to start and/or terminate at any desired elevation and/or angular direction about longitudinal axis A of support  20 . For instance, as shown in  FIGS. 1 and 22 , first conveying surface  33  of first spiral conveyor  32  has an input  36  from which an article may enter first conveying surface  33 . First conveying surface  33  also has an output  37  from which an article may exit first conveying surface  33 . Likewise, second conveying surface  35  of second spiral conveyor  34  has an input  38 , from which an article may enter second conveying surface  35 , and an output  39 , from which an article may exit second conveying surface  35 . Input  36 ,  38  of each first and second spiral conveyors  32 ,  34  may begin at a select elevation at any angular direction (e.g., from about 0 degrees to about 360 degrees) relative to longitudinal axis A. Output  37 ,  39  of each first and second spiral conveyors  32 ,  34  may also end at a select elevation at any angular direction (e.g., from about 0 degrees to about 360 degrees) relative to longitudinal axis A. Accordingly, each of inputs  36 ,  38  and/or outputs  37 ,  39  of first and second spiral conveyors  32 ,  34  may have the same and/or different angular directions and/or elevations. 
     For instance, as illustrated in  FIG. 22 , first conveying surface  33  has an input  36  located at first level  5  and oriented tangentially relative to the spiral path of first conveying surface  33  at or near a 9 o&#39;clock position in the frame of reference provided by  FIG. 22 . First conveying surface  33  extends upwardly about support  20  in a counterclockwise direction in the frame of reference provided by  FIG. 22  and has an output  37  located at second level  7  and oriented tangentially relative to the spiral path of first conveying surface  33  at or near a 6 o&#39;clock position in the frame of reference provided by  FIG. 22 , such that output  37  is oriented at about 90 degrees relative to input  36 . Second conveying surface  35  has an input  38  located at second level  6  and oriented tangentially relative to the spiral path of second conveying surface  35  at or near a 3 o&#39;clock position in the frame of reference provided by  FIG. 22 . Second conveying surface  35  extends downwardly about support  20  in a clockwise direction in the frame of reference provided by  FIG. 22  and has an output  39  located at first level  4  and oriented tangentially relative to the spiral path of second conveying surface  35  at or near a 12 o&#39;clock position in the frame of reference provided by  FIG. 22 , such that output  39  is oriented at about 90 degrees relative to input  38 . While the illustrated version shows each of first and second spiral conveyors  32 ,  34  having a single input  36 ,  38  and output  37 ,  39 , each of first and second spiral conveyors  32 ,  34  can have a plurality of inputs  36 ,  38  and/or outputs  37 ,  39 . Still other suitable configurations for conveyor assembly  30  will be apparent to one with ordinary skill in the art in view of the teachings herein. For example, while tangential inputs  36 ,  38  and outputs  37 ,  39  are shown, any one or more of inputs  36 ,  38  and/or outputs  37 ,  39  may be oriented non-tangentially relative to the spiral path of the respective conveying surface  33 ,  35 , such as obliquely relative to the spiral path of the respective conveying surface  33 ,  35 , or perpendicularly relative to the spiral path of the respective conveying surface  33 ,  35  in a manner similar to that shown in  FIG. 28 . 
     II. Exemplary Methods of Conveying 
     As discussed above, spiral conveyor system  10  is configured to transport articles  8  between at least one first level  4 ,  5  and at least one second level  6 ,  7  that is positioned at a different elevation than the at least one first level  4 ,  5 . In some versions, spiral conveyor system  10  is configured to transport articles  8  to additional levels above and/or below levels  4 ,  5 ,  6 ,  7 . Each of first and second spiral conveyors  32 ,  34  are configured to be selectively operated in an inclining and/or declining direction. First spiral conveyor  32  can be operated in the same and/or opposite inclining and declining direction as second spiral conveyor  34 . When first and second spiral conveyors  32 ,  34  are operated in the same direction, spiral conveyor system  10  is thereby operated in a multi-lane configuration such that each conveying surface  33 ,  35  of first and second spiral conveyors  32 ,  34  defines a lane that are both moving in the same select inclining or declining direction (e.g., both conveying surfaces  33 ,  35  are moving in the inclining direction or both conveying surfaces  33 ,  35  are moving in the declining direction). When first and second spiral conveyors  32 ,  34  are moving in opposing directions, spiral conveyor system  10  is thereby operated in a multi-directional configuration (e.g., first conveying surface  33  is moving in the inclining direction while second conveying surface  35  is moving in the declining direction or first conveying surface  33  is moving in the declining direction while second conveying surface  35  is moving in the inclining direction). 
     For instance,  FIG. 23A  shows first and second spiral conveyors  32 ,  34  moving simultaneously in a declining direction such that spiral conveyor system  10  is configured in a multi-lane declining configuration. As shown, first conveying surface  33  of first spiral conveyor  32  is moving in the declining direction such that an article  8   a  being transported thereon moves downward from an upper elevation at or near second level  7  to a lower elevation at or near first level  5 , as shown by article  8   c.  Similarly, second conveying surface  35  of second spiral conveyor  34  is moving in the declining direction such that an article  8   b  being transported thereon moves downward from an upper elevation at or near second level  6  to a lower elevation at or near first level  4 , as shown by article  8   d.    
       FIG. 23B  shows first and second spiral conveyors  32 ,  34  moving simultaneously in an inclining direction such that spiral conveyor system  10  is configured in a multi-lane inclining configuration. As shown, first conveying surface  33  of first spiral conveyor  32  is moving in the inclining direction such that an article  8   b  being transported thereon moves upward from a lower elevation at or near first level  5  to a higher elevation at or near second level  7 , as shown by article  8   d . Similarly, second conveying surface  35  of second spiral conveyor  34  is moving in the inclining direction such that an article  8   a  being transported thereon moves upward from a lower elevation at or near first level  4  to a higher elevation at or near second level  6 , as shown by article  8   c.    
       FIG. 23C  shows first and second spiral conveyors  32 ,  34  moving simultaneously in opposing directions such that spiral conveyor system  10  is configured in a first multi-directional configuration. As shown, first conveying surface  33  of first spiral conveyor  32  is moving in the declining direction such that an article  8   a  being transported thereon moves downward from an upper elevation at or near second level  7  to a lower elevation at or near first level  5 , as shown by article  8   c . Meanwhile, second conveying surface  35  of second spiral conveyor  34  is moving in the inclining direction such that an article  8   b  being transported thereon moves upward from a lower elevation at or near first level  4  to a higher elevation at or near second level  6 , as shown by article  8   d.    
       FIG. 23D  also shows first and second spiral conveyors  32 ,  34  moving simultaneously in opposing directions such that spiral conveyor system  10  is configured in a second multi-directional configuration. As shown, first conveying surface  33  of first spiral conveyor  32  is moving in the inclining direction such that an article  8   a  being transported thereon moves upward from a lower elevation at or near first level  5  to a higher elevation at or near second level  7 , as shown by article  8   c.  Meanwhile, second conveying surface  35  of second spiral conveyor  34  is moving in the declining direction such that an article  8   b  being transported thereon moves downward from an upper elevation at or near second level  6  to a lower elevation at or near first level  4 , as shown by article  8   d.  Still other methods for operating spiral conveyor system  10  will be apparent to one with ordinary skill in the art in view of the teachings herein. 
     In some versions, first and second spiral conveyors  32 ,  34  are configured to operate in a variety of modes. For instance, first and second spiral conveyors  32 ,  34  can be configured to operate in a transportation mode where the plurality of articles  8  move sequentially and simultaneously along a respective first and second conveying surface  33 ,  35  of first and second spiral conveyors  32 ,  34  to thereby transport the plurality of articles  8 . First and second spiral conveyors  32 ,  34  can also be configured to operate in an accumulation or storage mode where first and second conveying surfaces  33 ,  35  are moved in a first direction to load a plurality of articles  8  onto one or both of first and second conveying surfaces  33 ,  35  to thereby store the plurality of articles  8  on the one or both of first and second conveying surfaces  33 ,  35 . First and second conveying surfaces  33 ,  35  can then be moved to continue in the first direction and/or in an opposing second direction to unload the plurality of articles  8  from the one or both of the first and second conveying surfaces  33 ,  35 . Moreover, first and second spiral conveyors  32 ,  34  can be configured to operate in a recirculation mode such that the plurality of articles  8  can be unloaded and then reloaded onto one or both of first and second conveying surfaces  33 ,  35 . In some versions, first and second conveyors  32 ,  34  are simultaneously operated in the same mode (e.g., transportation, accumulation, storage, and/or recirculation mode). In some other versions, first and second conveyors  32 ,  34  are simultaneously operated in differing modes (e.g., transportation, accumulation, storage, and/or recirculation modes). 
     In some versions, a plurality of spiral conveyor systems  10  may be used to transport a plurality of articles  8  to a variety of levels  4 ,  5 ,  6 ,  7 .  FIG. 24  shows a conveyor system  15  incorporating two spiral conveyor systems  10 , though any suitable number of spiral conveyor systems  10  can be used. In the illustrated version, first spiral conveyor  32  has a first conveying surface input, shown as  33   a , at first level  5 . First spiral conveyor  32  then extends about support  20  of a first spiral conveyor system  10  such that first conveying surface is configured to move upwardly on first spiral conveyor system  10 , as shown by  33   b,  to second level  7 . First conveying surface then extends along second level  7 , as shown by  33   c.  First spiral conveyor  32  then extends about support  20  of a second spiral conveyor system  10  such that first conveying surface is configured to move downwardly on second spiral conveyor system  10 , as shown by  33   d,  to return to first level  5 . An output of first conveying surface then extends along first level  5 , as shown by  33   e.    
     Second spiral conveyor  34  has a second conveying surface input, shown as  35   a,  at first level  4 . Second spiral conveyor  34  then extends about support  20  of second spiral conveyor system  10  such that second conveying surface is configured to move upwardly on second spiral conveyor system  10 , as shown by  35   b,  to second level  6 . Second conveying surface then extends along second level  6 , as shown by  35   c.  Second spiral conveyor  34  then extends about support  20  of first spiral conveyor system  10  such that second conveying surface is configured to move downwardly on first spiral conveyor system  10 , as shown by  35   d,  to return to first level  4 . An output of second conveying surface then extends along first level  4 , as shown by  35   e.    
     While first and second spiral conveyors  32 ,  34  are shown to move in opposing directions from respective first levels  4 ,  5  to respective second levels  6 ,  7  and back to respective first levels  4 ,  5 , first and second spiral conveyors  32 ,  34  may be configured to move in similar directions to a variety of levels. For instance, first and second spiral conveyors  32 ,  34  may be configured to move from a second level  6 ,  7  to a first level  4 ,  5  and back to a second level  6 ,  7 . First and second spiral conveyors  32 ,  34  may also be configured to move to additional or alternative levels above and/or below levels  4 ,  5 ,  6 ,  7 . 
     III. A Second Exemplary Multi-Directional Spiral Conveyor System 
       FIGS. 25-26  show a second exemplary multi-directional spiral conveyor system  200  that is similar to spiral conveyor system  10 , except that spiral conveyor system  200  includes an additional third spiral conveyor  236 . As shown, spiral conveyor system  200  comprises a conveyor assembly  230  coupled with support  220 . Conveyor assembly  230  includes a first spiral conveyor  232  defining a first conveying surface  233  configured to transport a plurality of articles  8  thereon, a second spiral conveyor  234  defining a second conveying surface  235  configured to transport a plurality of articles  8  thereon, and a third spiral conveyor  236  defining a third conveying surface  237  configured to transport a plurality of articles  8  thereon. First, second, and third spiral conveyors  232 ,  234 ,  236  are positioned about support  20  in a triple helical configuration such that first, second, and third spiral conveyors  232 ,  234 ,  236  are interleaved in an alternating configuration about longitudinal axis A of support  20 . Accordingly, conveyor system  200  is configured to provide an additional third spiral conveyor  236  to the double helical configuration of conveyor system  10  to form a triple helical configuration. 
     Each of first, second, and third conveying surfaces  233 ,  235 ,  237  are configured to selectively move in an inclining direction to transport the plurality of articles  8  upward and/or a declining direction to transport the plurality of articles  8  downward. Accordingly, spiral conveyor system  200  can be configured to operate in one or both of a multi-directional configuration and a multi-lane configuration. For instance, each of first, second, and third conveying surfaces  233 ,  235 ,  237  can be simultaneously moved in the same direction, either inclining or declining, such that spiral conveyor system  10  is operated in a multi-lane configuration. One of first, second, and third conveying surfaces  233 ,  235 ,  237  can be moved in an opposing direction relative to the other two conveying surfaces  233 ,  235 ,  237  such that spiral conveyor system  10  is operated in a multi-directional configuration. Still other suitable configurations for spiral conveyor system  200  will be apparent to one with ordinary skill in the art in view of the teachings herein. 
     III. A Third Exemplary Multi-Directional Spiral Conveyor System 
       FIGS. 27-28  show a third exemplary multi-directional spiral conveyor system  300  that is similar to spiral conveyor system  10 , except that spiral conveyor system  300  forms a non-circular configuration such as a semi-elliptical configuration. As shown, spiral conveyor system  300  comprises a conveyor assembly  330  coupled with support  320 . While only one spiral conveyor is shown, conveyor assembly  330  can include two or more spiral conveyors that define a conveying surface configured to transport a plurality of articles  8  thereon. Such spiral conveyors can be positioned about support  320  in a generally helical configuration such that the spiral conveyors are interleaved in an alternating configuration about support  320 . In the illustrated version, conveyor assembly  330  includes a pair of curved portions  340  and a pair of substantially straight portions  342  positioned between curved portions  340  to form a substantially elliptical shape. Accordingly, conveyor assembly  330  may be positioned about or around an obstacle  9 , such as a building pillar, to optimize the position of conveyor assembly  330 . Still other suitable configurations for conveyor assembly  330  can be used. For instance, one or more curved portions  340  and one or more straight portions  342  can be used to form any suitable non-circular shape of conveyor assembly  330 . 
     Conveyor system  300  further comprises one or more radial conveyor sections  350  extending outwardly relative to conveyor assembly  330  such that radial conveyor sections  350  are oriented substantially perpendicularly relative to conveyor assembly  330 . Accordingly, radial conveyor sections  350  are configured to transfer articles conveyed on conveyor system  300  into and/or out of conveyor assembly  330 . In the illustrated version, a respective transfer device  352  is positioned at an intersection between each radial conveyor section  350  and conveyor assembly  330 . Each transfer device  352  is configured to transfer an article between each radial conveyor section  350  and conveyor assembly  330  to change the direction of the article between each radial conveyor section  350  and conveyor assembly  330 . For instance, transfer device  352  can be a pop-up lateral belt transfer device. Still other suitable configurations for transfer device  352  can be used. 
     IV. Examples 
     The following examples relate to various non-exhaustive ways in which the teachings herein may be combined or applied. It should be understood that the following examples are not intended to restrict the coverage of any claims that may be presented at any time in this application or in subsequent filings of this application. No disclaimer is intended. The following examples are being provided for nothing more than merely illustrative purposes. It is contemplated that the various teachings herein may be arranged and applied in numerous other ways. For example, each of the conveying surfaces may be operated at any desired speed, continuously or intermittingly. It is also contemplated that some variations may omit certain features referred to in the below examples. Therefore, none of the aspects or features referred to below should be deemed critical unless otherwise explicitly indicated as such at a later date by the inventors or by a successor in interest to the inventors. If any claims are presented in this application or in subsequent filings related to this application that include additional features beyond those referred to below, those additional features shall not be presumed to have been added for any reason relating to patentability. 
     EXAMPLE 1 
     A spiral conveyor system configured to transport a plurality of articles thereon between at least one first level and at least one second level having a different elevation than the at least one first level, wherein the spiral conveyor system comprises: a support extending generally vertically between the at least one first level and the at least one second level, wherein the support defines a longitudinal axis; and a conveyor assembly coupled with the support, wherein the conveyor assembly comprises: a first spiral conveyor defining a first conveying surface configured to transport the plurality of articles thereon, and a second spiral conveyor defining a second conveying surface configured to transport the plurality of articles thereon, wherein the second conveying surface is independently operable relative to the first conveying surface, wherein the first and second spiral conveyors are positioned around the support in a double helical configuration such that the first and second spiral conveyors are interleaved in an alternating configuration about the longitudinal axis of the support between the at least one first level and the at least one second level. 
     EXAMPLE 2 
     The spiral conveyor system of example 1, wherein each of the first and second conveying surfaces are respectively configured to selectively move in an inclining direction and in a declining direction, wherein the first and second conveying surfaces are respectively configured to move upwardly from a lower elevation to a higher elevation in the inclining direction, and wherein the first and second conveying surfaces are respectively configured to move downwardly from a higher elevation to a lower elevation in the declining direction. 
     EXAMPLE 3 
     The spiral conveyor system of example 2, wherein the first and second conveying surfaces are configured to move in opposing directions when the spiral conveyor system is in a multi-directional configuration. 
     EXAMPLE 4 
     The spiral conveyor system of example 2, wherein the first and second conveying surfaces are configured to move in the same direction when the spiral conveyor system is in a multi-lane configuration. 
     EXAMPLE 5 
     The spiral conveyor system of any of examples 1 through 4, wherein the support comprises a plurality of arms extending outward from the support and coupled to the conveyor assembly to support the conveyor assembly. 
     EXAMPLE 6 
     The spiral conveyor system of example 5, wherein each arm is longitudinally and rotationally offset relative to an adjacent arm relative to the longitudinal axis of the support. 
     EXAMPLE 7 
     The spiral conveyor system of either example 5 or 6, wherein each arm is coupled to the support at a select height along the support. 
     EXAMPLE 8 
     The spiral conveyor system of any of examples 1 through 7, wherein each of the first and second spiral conveyors respectively comprise a pair of side walls and a plurality of rollers extending between the side walls, wherein each roller of the plurality of rollers respectively defines the first and second conveying surfaces. 
     EXAMPLE 9 
     The spiral conveyor system of example 8, wherein each roller is tapered from a first end to a second end. 
     EXAMPLE 10 
     The spiral conveyor system of either of examples 8 or 9, wherein the plurality of rollers are interconnected via at least one O-band, wherein at least one roller of the plurality of rollers is coupled with a motor such that the motor is configured to drive the plurality of rollers. 
     EXAMPLE 11 
     The spiral conveyor system of any of examples 1 through 11, wherein the first spiral conveyor defines a first rise, wherein the second spiral conveyor defines a second rise. 
     EXAMPLE 12 
     The spiral conveyor system of example 11, wherein the first rise is substantially equal to the second rise. 
     EXAMPLE 13 
     The spiral conveyor system of any of examples 1 through 12, wherein the first conveying surface includes a first input and a first output, wherein the second conveying surface includes a second input and a second output, wherein each of the first and second inputs and each of the first and second outputs are respectively positioned at a select angular direction relative to the longitudinal axis of the support. 
     EXAMPLE 14 
     A conveyor system configured to transport a plurality of articles thereon, wherein the conveyor system includes more than one spiral conveyor system of any of the examples 1 through 13. 
     EXAMPLE 15 
     The spiral conveyor system of any of examples 1 through 14, wherein the conveyor assembly further comprises a third spiral conveyor defining a third conveying surface configured to transport the plurality of articles thereon, wherein the third conveying surface is independently operable relative to both the first and second conveying surfaces, wherein the first, second, and third spiral conveyors are positioned about the support in a triple helical configuration such that the first, second, and third spiral conveyors are interleaved in an alternating configuration about the longitudinal axis of the support between the at least one first level and the at least one second level. 
     EXAMPLE 16 
     The spiral conveyor system of any of examples 1 through 15, wherein each of the first and second spiral conveyors include one or more curved portions and one or more straight portions to form a quasi-helical shape. 
     EXAMPLE 17 
     The spiral conveyor system of any of examples 1 through 16 further comprising one or more radial conveyor sections extending substantially perpendicular relative to the first and second spiral conveyors such that the plurality of articles can be transferred between the one or more radial conveyor sections and the first and second spiral conveyors. 
     EXAMPLE 18 
     A spiral conveyor system configured to transport a plurality of articles thereon between at least one first level and at least one second level having a different elevation than the at least one first level, wherein the spiral conveyor system comprises: a support extending generally vertically at least between the at least one first level and the at least one second level, wherein the support defines a longitudinal axis; and a conveyor assembly comprising a plurality of spiral conveyors, wherein each spiral conveyor of the plurality of spiral conveyors defines a conveying surface configured to transport the plurality of articles thereon, wherein each spiral conveyor is coupled with the support in a helical configuration such that each spiral conveyor is interleaved in an alternating configuration with at least one other spiral conveyor of the plurality of spiral conveyors of the conveyor assembly about the longitudinal axis of the support between the at least one first level and the at least one second level. 
     EXAMPLE 19 
     The spiral conveyor system of example 18, wherein the conveying surface of each spiral conveyor of the plurality of spiral conveyors is configured to selectively move in an inclining direction or in a declining direction, wherein the conveying surface is configured to move upwardly from a lower elevation to a higher elevation in the inclining direction, and wherein the conveying surface is configured to move downwardly from a higher elevation to a lower elevation in the declining direction. 
     EXAMPLE 20 
     A spiral conveyor system configured to transport a plurality of articles thereon, wherein the spiral conveyor system comprises: a support extending generally vertically, wherein the support defines a longitudinal axis; and a conveyor assembly coupled with the support, wherein the conveyor assembly comprises: a first spiral conveyor defining a first conveying, wherein the first conveying surface is configured to move in a select one of an inclining direction and a declining direction between a respective first and second elevation of the first spiral conveyor, and a second spiral conveyor defining a second conveying surface, wherein the second conveying surface is independently operable from the first conveying surface, wherein the second conveying surface is configured to move in a select one of an inclining direction and a declining direction between a respective first and second elevation of the second spiral conveyor, wherein the spiral conveyor system is configured to operate in a select one of a multi-directional configuration and a multi-lane configuration, wherein the first conveying surface is configured to move in an opposing inclining or declining direction relative to the second conveying surface when the spiral conveyor system is in the multi-directional configuration, and wherein the first conveying surface is configured to move in the same inclining or declining direction as the second conveying surface when the spiral conveyor system is in the multi-lane configuration. 
     Having shown and described various embodiments of the present innovation, further adaptations of the methods and systems described herein may be accomplished by appropriate modifications by one of ordinary skill in the art without departing from the scope of the present innovation. Several of such potential modifications have been mentioned, and others will be apparent to those skilled in the art. For instance, the examples, embodiments, geometrics, materials, dimensions, ratios, steps, and the like discussed above are illustrative and are not required. Accordingly, the scope of the present innovation should be considered in terms of the following claims and is understood not to be limited to the details of structure and operation shown and described in the specification and drawings.