Abstract:
A knockdown reel is designed to be readily and swiftly assembled out of five or six components, all but two of which can be fabricated of plywood, composite board and/or cardboard. An annular fastener secures the components so as to withstand stresses associated with transport and handling, as well as stresses associated with the winding and unwinding process.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     Reels or spools of various sizes and configurations are used for storing and transporting flexible materials of the type that can be wound around a cylindrical core. In the industrial setting, reels are used to store wire and cable product of various gauges. Such reels typically comprise a cylindrical core, commonly referred to as a barrel or drum, about which the product is coiled. To protect the product during shipment and handling, the barrel is attached at either end to a disc-shaped flange.  
         [0002]     In order to reduce shipping costs, reels are commonly transported in the form of their disassembled components, i.e., detached barrels and flanges. Reels that can be readily assembled from their components are known as “knockdown” reels. Knockdown reels must be capable of being assembled from their components quickly and easily, yet such reels must also have the structural strength to withstand several different types of stress.  
         [0003]     Since the product stored on a reel is often heavy and bulky, it exerts considerable axial force outward on the flanges. Reels are often lifted by one of the flanges, so the connections between the flange and the barrel must be able to support the full weight of the loaded reel. When the wire or cable is being wound or unwound on the reel, it exerts a large centripetal/centrifugal force on the barrel, tending to collapse the barrel during the winding process and tending to split the barrel open during the unwinding process. When a reel is dropped during transport or handling, a sudden inward axial force can impinge upon one or both of its flanges, as well as upon the flange-barrel connections.  
         [0004]     In addition to these daunting structural challenges, marketplace realities dictate that reels be made of the least expensive materials available. It is a great advantage, therefore, to retain the option of fabricating a reel using a variety of materials, and to thereby be able to select the least expensive materials based on prevailing market conditions.  
         [0005]     When one surveys the prior art in this field, however, one does not find a design which addresses each of the three identified requisites for an optimal knockdown reel: (a) rapidly assemblable from its components, (b) structural strength to withstand lifting, winding/unwinding and/or dropping, (c) flexibility in selection of component materials.  
         [0006]     In the prior art, we find two basic types of knockdown reels. The first type are those that are designed to be fabricated exclusively or primarily with plastic and/or metal components. In these designs, the attachment of the barrel to the flanges is secured by locking mechanisms consisting of a flexible male member which temporarily bends or deforms to fit into a conjugate female member. In order to lock into place within the female member, the male member must be made of a resilient material which, after deformation within a certain range, will resume its original configuration.  
         [0007]     In the prior art, there are several examples of knockdown reels utilizing resilient locking mechanisms: Hacker, U.S. Pat. No. 3,552,677 (flexible “stems” #52 projecting from barrel ends snap into “apertures” #56 in flanges, FIGS. 3 and 6); Crellin, U.S. Pat. No. 3,785,584 (yieldable “projections” #42 from barrel ends engage resilient “tongues” #22 in flanges, FIGS. 3 and 4); Campbell, U.S. Pat. No. 3,822,841 (flexing “latch members” #24 from barrel ends insert into “openings” #40 in flanges, FIGS. 3, 5, 6 and 12); McCaffrey, U.S. Pat. No. 4,903,913 (yielding “detents” #80-85 from barrel ends fit into “openings” #70-74 in flanges, FIGS. 4 and 5); Campbell, U.S. Pat. No. 5,575,437 (flexing “latch fingers” #24 from barrel ends snap into “openings” #40 in flanges, FIGS. 2, 8 and 10).  
         [0008]     Leunig, U.S. Pat. No. 4,471,919, uses flexible barrel halves (#18 and 20) with a resilient hinge #22 to interlock with a camming element #52 in the flange (FIG. 2-4). In Bulman, U.S. Pat. No. 5,743,486, the barrel threads into the flange and is locked in place by mating resilient annular locking rings in the barrel #14 and flange #19 (FIGS. 6 and 7).  
         [0009]     All of the foregoing knockdown reel designs depend on the resilient qualities of plastic or metal components which yieldingly fit together. This presents an economic disadvantage insofar as the use of less expensive wooden, composite board and/or cardboard components is thereby precluded. Another disadvantage of these designs is their vulnerability to inward axial stress on the flanges, such as occurs when a reel is dropped. Such inward forces will tend to compress the flange against the end of the barrel, potentially causing the resilient plastic/metal male member of the locking mechanism to deform and relax its grip within the female member. To the extent such designs have segmented flexible barrels using resilient interlocks (e.g., Leunig, FIG. 3, #30 and 32), they are also vulnerable to outward radial stress on the barrel during the unwinding process.  
         [0010]     While there are knockdown reel designs that avoid the need for a resilient locking mechanism, e.g., Campbell, U.S. Pat. No. 3,940,085, and Witwer et al., U.S. Pat. No. 5,806,788, they depend upon threaded bolts (Campbell #32, FIG. 2; Witwer #54, FIG. 2) to attach the barrel to the flanges, thus making the assembly process excessively laborious and time consuming.  
         [0011]     Therefore, the prior art falls short of fulfilling the three criteria for an optimal breakdown reel design, with respect to economical selectability of the most component materials, structural integrity under inward axial and outward radial stresses, and speed of assembly.  
       SUMMARY OF THE INVENTION  
       [0012]     The present invention represents a significant improvement over the prior art with respect to its ability to use inexpensive wooden, composite board and/or cardboard components. A pair of flanges which are disc-shaped with an inner surface and an outer surface are fabricated of plywood or any other strong, durable composite board, such as hardboard or oriented strand board. A barrel can be either an integral barrel or a split-barrel. The integral barrel comprises one cylindrical core, while the split-barrel comprises two semi-cylindrical half-cores. In either mode, the barrel is made of cardboard tubing reinforced at either end by collars made of plywood, composite board or laminated cardboard. In the preferred embodiment, each collar fits within interior annular routing on the inner surface of the corresponding flanges. Alternately, the collar may be recessed within the barrel, such that only the cardboard tubing fits within the interior annular routing. Multiple apertures in the collar are aligned with matching fastening holes within the interior annular routing in the flange. The fastening holes extend through the flange to the outer surface of the flange, where the fastening holes emerge within exterior annular routing.  
         [0013]     The exterior annual routing of the flange is formed to accept an annular fastener, which is made of rigid metal or plastic. The annular fastener comprises a flat annular ring to which are riveted, at equally spaced intervals around the ring, multiple projecting fingers, each having a tip and a base. The number of fingers corresponds to the number of fastening holes in the flange. Each finger comprises a composite of multiple segments, which are cylindrical or frustrum-shaped. In the preferred embodiment, the segments all have the same diameter, which is slightly less than the diameter of the fastening holes in the flange. Alternately the segments can decrease in diameter from the base to the tip of the finger, with the segment at the tip of each finger having a diameter slightly less than the diameter of the fastening holes in the flange. In another alternate embodiment, one of the fingers is longer than the others in order to serve as a guide in aligning the fastening holes of the flange with the apertures of the collar.  
         [0014]     A knockdown reel according to the present invention can be quickly assembled by attaching one flange to each end of the barrel. The flanges are attached to the barrel one at a time by first inserting the collar (in the case of the integral barrel) or collars (in the case of the split barrel) into the interior annular routing and aligning the apertures of the collar(s) with the fastening holes. The fingers of the annular fastener are then inserted into the fastening holes through the exterior annular routing, and pressure is applied to the ring to drive the fingers through the flange and into the apertures of the collar(s). Upon the completion of this operation, the ring is secured within the exterior annular routing, and the collar(s) of the barrel are secured within the interior annular routing.  
         [0015]     Since the annular fastener is inserted through the outer surface of the flange, it is relatively invulnerable to loosening by inward axial forces on the flange, such as occur when the reel is dropped. Due to the configuration of the segments comprising the fingers of the annular fastener, the fingers are retained tightly within the collar(s) of the barrel and can withstand outward axial forces on the flange, such as occur when the reel is lifted. Because the ring of the annular fastener interconnects all of the fingers, the fingers serve to reinforce the barrel with respect to centripetal radial stresses tending to collapse its core, as well as centrifugal radial stresses tending to open its core (in the case of the integral barrel) or separate its half-cores (in the case of the split barrel).  
         [0016]     Therefore, the present invention fulfills the three identified objectives with respect to an optimal breakdown reel. It retains the optional economical use of multiple component materials; it is easily and quickly assembled; and it is structurally sound under the four probable stress modes: axial inward, axial outward, radial centripetal and radial centrifugal. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]      FIG. 1  is a side perspective view of the disassembled components of a knockdown reel having a split-barrel configuration.  
         [0018]      FIG. 2  is a front perspective view of one of the two half-cores of a split-barrel.  
         [0019]      FIG. 3  is a front elevation view of a flange.  
         [0020]      FIG. 4  is a side perspective view of an annular fastener.  
         [0021]      FIG. 5  is a rear elevation and cross-sectional view of a flange and an annular fastener.  
         [0022]      FIG. 6  is a front perspective view of the attachment of a split-barrel to one flange.  
         [0023]      FIG. 7  is a front perspective view of the attachment of a split-barrel to a second flange.  
     
    
     DESCRIPTION OF THE INVENTION  
       [0024]     As shown in  FIG. 1 , a breakdown reel  10  having the features of the present invention comprises a barrel  11  and two flanges  12 . In the preferred embodiment shown in  FIG. 1 , the reel has a split-barrel comprising two semi-cylindrical half-cores  13 . Alternately, the reel  10  can have an integral barrel comprising one cylindrical core (not shown).  
         [0025]     As shown in  FIG. 2 , one of the half-cores  13  comprises semi-cylindrical tubing  14  reinforced at either end by two arcuate collars  15 . Drilled through each of the collars are multiple apertures  16 . In the preferred embodiment, the tubing  14  is made of cardboard and the collars of plywood, composite board or laminated cardboard. In the alternative integral barrel configuration (not shown), the core is reinforced at either end by two annular collars also having multiple aperatures drilled through them.  
         [0026]     The flanges are disc-shaped panels preferably having a thickness of 5/16″ to ⅜″. The flanges are fabricated of plywood or any other strong, durable composite board, such as hardboard or oriented strand board. As shown in  FIG. 1 , each of the flanges  12  comprises an inner surface  17  and an outer surface  18 . In the center of the flange is an axial opening  19 , through which a shaft (not shown) can be extended to support the reel  10  during the winding/unwinding process. On the inner surface  17  of the flange  12 , concentrically disposed about the axial opening  19 , is an interior annular routing  20 .  
         [0027]     Referring to  FIG. 3 , the interior annular routing  20  has an outer diameter slightly greater than the diameter of the barrel  11  and an inner diameter slightly less than the inner diameter of the collar(s), such that the end of the joined half-cores  13  of the split-barrel  11 , or alternately the end of the core of the integral barrel (not shown), fits snugly within the interior annular routing  20 . In the preferred embodiment, the interior annular routing  20  has a depth of ⅛″.  
         [0028]     In an alternate embodiment, the collar(s)  15  are recessed within the barrel  11  at the same depth as the depth of the interior annular routing  20 , such that only the tubing  14  fits within the interior annular routing  20 , while the collar(s)  15  engage the inner surface  17  of the flange  12  within the inner diameter of the interior annular routing  20 .  
         [0029]     As shown in  FIG. 3 , drilled through the flange  12  within the interior annular routing  20  are multiple fastening holes  21 . The fastening holes  21  are distributed uniformly around the interior annular routing  20  and are alignable with the apertures  16  in the collar(s)  15  of the barrel  11 . The fastening holes and the apertures have the same diameter, preferably ¼″.  
         [0030]     As shown in  FIG. 1  and  FIG. 5 , on the outer surface  18  of the flange  12 , concentrically disposed about the axial opening  19 , is an exterior annular routing  22 . The exterior annular routing  22  has an outer diameter equal to the outer diameter of the interior annular routing  20 . Distributed uniformly around the exterior annular routing  22  are the fastening holes  21 . The exterior annular routing is formed to accept an annular fastener  23  made of rigid metal or plastic.  
         [0031]     Referring to  FIG. 4 , the annular fastener  23  comprises a flat ring  24  to which are riveted at uniform intervals multiple projecting fingers  25 , each of which has a tip  26  and a base  27 . Each finger  25  comprises a composite of multiple segments  28 , which are cylindrical or frustrum-shaped. In the preferred embodiment, the segments all have the same outer diameter, which is slightly less than the diameter of the fastening holes  21  in the flange  12 . Alternately, as shown in  FIG. 4 , the segments can have a stepped diameter which decreases from the base  27  to the tip  26 , with the segment at the tip having an outer diameter slightly less than the diameter of the fastening holes  21  in the flange  12 .  
         [0032]     The ring  24  of the annular fastener  23  is dimensioned to fit snuggly within the exterior annular routing  22 . In the preferred embodiment, the ring  24  is 1/32″ thick and the exterior annular routing is 1/16″ deep.  
         [0033]     In an alternate embodiment, the exterior annular routing  22  is not present, and the annular fastener  23  engages the outer surface  18  of the flange  12  with the fingers  25  projecting into the fastening holes  21 . In another alternate embodiment, one of the fingers  25  is longer than the others in order to serve as a guide for aligning the fastening holes  21  with the apertures  16  of the collar(s)  15 . In yet another alternate embodiment, plastic sleeves (not shown) are inserted into the apertures  16  such that, when the flange  12  is attached to the barrel  11 , the plastic sleeves extend into the fastening holes  21 . The interior of each of the sleeves is formed to correspond conjugately to the profile of the segments  28  of each finger  22  of the annular fastener  23 , such that when the finger is inserted into the sleeve, the sleeve expands within the fastening hole  21  and the aperture  16  and thereby locks the annular fastener in place.  
         [0034]     As shown in  FIG. 6 , to assemble the knockdown reel  10 , the flanges  12  are attached to the barrel  11  one at a time. For the split-barrel configuration, the two half-cores  13  are joined together and the collars  15  are inserted into the interior annular routing  20  of the flange  12  with the apertures  16  aligned with the fastener holes  21 . Then the annular fastener  23  is inserted into the exterior annular routing  22  such that the fingers  25  penetrate the fastener holes  21 . Pressure is then applied to the annular fastener  23  so as to force the fingers  25  through the flange  12  and into the apertures  16  of the collars  15 . When this operation is complete, the ring  24  is secured within the exterior annular routing  22  and the collars  15  are secured within the interior annular routing. As depicted in  FIG. 7 , the same process is then repeated to attach the second flange  12  to the other end of the barrel  11 .  
         [0035]     The present invention, therefore, is readily and speedily assemblable from five or six component parts which can be fabricated of plywood, composite board and/or cardboard, except in the annular fastener  23 . The annular fastener  23  provides structural strength under both inward and outward axial stresses on the flanges  12 , as well as under both centripetal and centrifugal radial stresses on the barrel  11 .  
         [0036]     While the current invention has been described in some detail with reference to certain currently preferred embodiments, other embodiments are feasible and will readily suggest themselves to those skilled in the art. Therefore, the spirit and scope of the appended claims are not limited to the description of the preferred embodiments contained herein.