Abstract:
A reel comprises a cylindrical core composed of two complementary arcuate core segments, a pair of flanges disposed respectively at axially spaced opposite ends of the core, and a pair of rings for connecting the core to the flanges. The rings are fixed respectively to facing inner sides of the flanges. Cooperating slots and tongues on the rings and core elements prevent the flanges from moving relative to the core in the direction of the axis of the core. The tongues enter the slots when the core segments are brought together. Resiliently bendable locking arms protrude radially inward from both ends of each core segment, and each locking arm is engageable by a snap fit with one of the rings when the core segments are brought together. Access openings in the flanges adjacent each of the locking arms allow access to the locking arms for disengagement from the rings.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit under 35 USC §119(e) of U.S. Provisional Patent Application No. 61/324,377, filed Apr. 15, 2010. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to reels, and more particularly to a reel for storing and transporting cable, wire, flexible tubing or the like, which can be readily disassembled after the supply of cable or the like is exhausted to facilitate shipment to a location where the reel can be reassembled and replenished with a supply of cable or the like. 
     BACKGROUND OF THE INVENTION 
     In the wire and cable industry, it is conventional practice to ship wire or cable wound on reels to a user. After unwinding the wire or cable from the reel, the user either disposes of the reel, or returns the reel for re-use. 
     A reel is composed of a cylindrical drum or core having flanges at its opposite ends for retaining cable, wire, or the like wound around the drum. To facilitate shipment of exhausted reels, various knockdown or collapsible reels have been designed. In a typical knockdown reel, the core is composed of two complementary, interlocking, semi-cylindrical parts which, when together, provide a circular, cylindrical outer surface. The two semi-cylindrical parts interlock with a pair of flanges to form a complete reel. 
     One such knockdown reel is described in U.S. Pat. No. 3,940,085, granted Feb. 24, 1976 to Kenneth E. Campbell. In the reel described in the Campbell patent, each of two semi-cylindrical core halves is formed with an arcuate ridge at both of its ends. The ridges are received in annular grooves formed in bosses on a pair of flanges. The core halves are secured to each other by bolts, and when they are secured together, the arcuate ridges are locked in the annular grooves, and the core and flanges are rigidly held together. 
     Another knockdown reel is described in U.S. Pat. No. 5,575,437, granted Nov. 19, 1997 to Kenneth E. Campbell. In this reel, semi-cylindrical core halves are connected to circular recesses in specially formed flanges by means of resilient, axially extending, latching fingers. 
     In still another knockdown reel, described in U.S. Pat. No. 5,806,788, granted on Sep. 15, 1998 to Richard P. Witwer and Kenneth E. Campbell, core halves are formed with locking fingers that engage notches formed on the peripheries of core-supporting hubs fastened to flanges. 
     Although the knock-down reels described in these patents have served reliably in the cable industry for many years, there remains a need for a more robust reel that can withstand impact, temperature variations and other forms of stress more reliably. For example, it is important for a reel to be able to withstand the impact that results when it is dropped from a fork lift or from the bed of a flat bed trailer. 
     SUMMARY OF THE INVENTION 
     The reel according to the invention comprises a cylindrical core composed of two complementary arcuate core segments, a pair of flanges disposed respectively at axially spaced opposite ends of the core, and a pair of rings for connecting the core to the flanges. The rings are fixed respectively to mutually facing inner sides of the flanges. Cooperating slots and tongues on the rings and core elements prevent the flanges from moving relative to the core in the direction of the axis of the core. The tongues enter the slots when the core segments are brought together. Resiliently bendable locking arms protrude radially inward from both ends of each core segment, and each locking arm is engageable by a snap fit with one of the rings when the core segments are brought together. 
     Preferably, access openings are provided in the flanges adjacent each of the locking arms to allow access to the locking arms for disengagement from the rings. 
     More particularly, a preferred embodiment of the reel comprises a core having a substantially circular cylindrical outer surface symmetrical about a core axis. The core is composed of a plurality of complementary, connected, arcuate core segments, and has two axially spaced opposite ends. Flanges are disposed respectively at the axially spaced opposite ends of the core, and have inner sides facing each other. Rings for connecting the core to the flanges, are fixed to the inner sides of the flanges whereby the rings are located opposite to each other. 
     Arc-shaped connecting are elements formed on the core segments at the opposite ends of the core, and arc-shaped connecting elements are also formed on the rings. The arc-shaped connecting elements of the core segments are engageable with the arc-shaped connecting elements formed on the rings and are fully engaged when the arcuate core segments are in complementary relationship to form a core having a circular cylindrical outer surface. The cooperation of the arc-shaped connecting elements locks the flanges against axial movement relative to the core. The arc-shaped connecting elements of the core segments are movable radially outward relative to the core axis for disengagement from the arc-shaped connecting elements formed on the rings. 
     Locking arms are connected to, and extend radially inward from, both ends of each core segment. The locking arms have end portions with radially outward facing locking surfaces. These locking arms are resiliently bendable so that their end portions can move through a limited range in a direction substantially parallel to the core axis. Each ring has radially extending slots for receiving the locking arms, so that the locking arms can move radially inward in the slots when the arc-shaped connecting elements of the core segments are engaged with the arc-shaped connecting elements formed on the rings. Each slot of each ring has a wall facing the opposite ring, the wall being positioned for sliding engagement with a locking arm and for bending the locking arm toward the opposite ring as the locking arm moves radially inward. Each wall also has a radially inward facing surface for locking engagement with a radially outward facing surface of a locking arm. The inwardly facing surfaces of the walls and the outwardly facing surfaces of the locking arms are positioned for automatic engagement with each other by resilient movement of the arms when the arc-shaped connecting elements of the core segments are fully engaged with the arc-shaped connecting elements formed on the rings. The end portion of each locking arm that has a radially outward facing surface engaged with a radially inward facing surface of a wall of a ring, is movable toward the opposite ring for disengagement of the engaged surfaces. 
     Preferably, the flanges have access apertures in register with the end portions of the locking arms, whereby axial pressure can be applied to the end portions of the locking arms to disengage the radially outward facing surfaces of the locking arms from the radially inward facing surfaces of the walls of the rings. 
     The resiliently bendable locking arms can be unitary parts of the cores segments. Alternatively, each of the locking arms can comprise a resilient metal sheet fastened to one of the core segments, and a resin block secured to the metal sheet and engageable by a snap fit with one of the rings. 
     In a preferred embodiment, the arc-shaped connecting elements formed on the core segments are radially inward facing slots, and the arc-shaped connecting elements formed on the rings are annular elements protruding radially outward. Each said annular element extends into one of the radially inward facing slots. 
     In the preferred embodiment, each of the radially extending slots of each ring is defined by the wall thereof and a pair of opposed sides protruding from the wall in spaced relationship to each other toward the opposite ring. The opposed sides are progressively closer to each other proceeding radially inward toward the core axis so that each slot is tapered. Each core segment includes a pair of rigid elements adjacent each of its locking arms. These rigid elements protrude substantially radially inward, and are circumferentially spaced from each other on opposite sides of the adjacent locking arm. The rigid elements have circumferentially facing outer sides that are also progressively closer to each other proceeding radially inward. These outer sides conform to and engage the opposed sides of a radially extending slot when the outwardly facing surface of the adjacent locking arm is engaged with the inwardly facing surface of the wall of the last-mentioned slot. 
     In the embodiment having rigid elements adjacent the locking arms, a rib extending axially along each core element is preferably provided to connects the rigid elements adjacent the locking arm at one end of each core segment to the rigid elements adjacent the locking arm at the other end thereof, thereby ensuring that the rigid elements are firmly supported in fixed relationship to the core segment. 
     The rigid elements adjacent each locking arm also preferably extend substantially radially inward beyond the innermost end of the adjacent locking arm to protect the locking arm from damage, especially when the core segments are stacked for shipment or storage. 
     The reel according to the invention is highly robust. Its overall strength, and the strength of the connections of the core components to the rings, are sufficiently high that the reel can withstand impact, temperature changes, and other stresses with a very low incidence of failure. At least the core and ring portions, and often the entire reel including the flanges, can be disassembled and re-used repeatedly without failure. Moreover, the reel can be assembled and disassembled quickly and easily by an individual worker without the use of tools. 
     Further objects and advantages of the invention will be apparent from the following description when read in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of a reel in accordance with the invention; 
         FIG. 2  is a broken-away end view of the reel; 
         FIG. 3  is a sectional view taken on plane  3 - 3  in  FIG. 2 ; 
         FIG. 4  is a sectional view taken on plane  4 - 4  in  FIG. 2 ; 
         FIG. 5  is a sectional view taken on plane  5 - 5  in  FIG. 2 ; 
         FIG. 6  is a perspective view showing details of the inside of one of the two core halves  10  and  12 ; 
         FIG. 7  is a fragmentary elevational view of a part of an attachment ring; 
         FIG. 8  is an exploded view showing an alternative locking arm composed of a resilient strip of sheet metal and a resin block; and 
         FIG. 9  is a sectional view corresponding to  FIG. 4  but showing the alternative locking arm engaged with a wall  56 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As shown in  FIG. 1 , a preferred embodiment of the reel according to the invention comprises two complementary arc-shaped segments  10  and  12 , which can be connected together to form a core  14  having a substantially circular, cylindrical outer surface symmetrical about a core axis. Each segment has two opposite edges, each having a row of tabs  16  and a row of slots  18  ( FIG. 6 ), the tabs and slots being arranged in alternating relationship. When the segments are joined, the tabs of each segment fit into the slots of the other segment. 
     Although the core is preferably composed of two complementary arc-shaped segments, it is possible to form the core from three or more complementary arc-shaped segments whose arcs subtend angles totalling 360 degrees. 
     Flanges  20  and  22  are disposed respectively at axially spaced opposite ends of the core. The flanges, which are typically composed of wood, although other suitable materials can be used, can be identical, and have inner sides facing each other. The inner side  24  of flange  20  is visible in  FIG. 1 . 
     Rings are fixed respectively to the inner sides of flanges  20  and  22 , one such ring is ring  26  in  FIG. 1 . The rings are preferably identical and can be fastened to the flanges by means of bolts  28  ( FIGS. 2 and 3 ). The bolts extend through holes  30  in the rings, and through corresponding holes  32  ( FIG. 3 ) in the flanges  20  and  22 , holes  32  being aligned with holes  30 . As shown in  FIG. 3 , the heads  34  of the bolts are disposed in recesses  36  in the flanges. The bolts are secured to the rings by nuts  38 . For added strength, the recesses in the flanges can be lined with metal cup washers (not shown). 
     Each ring has a series of radially outward protruding annular parts, one such part  40  being seen in  FIG. 3 . Part  40  is spaced from the inner side  24  of the adjacent flange  22  to provide a space  42  for receiving an inwardly protruding part  44  of an arc-shaped segment  12 . 
     A wall  46  extends inwardly from the outer part of the arc-shaped segment  12  as a unitary part thereof, and is reinforced by longitudinally extending ribs, which are also formed as unitary parts of the arc-shaped segment, one such rib being rib  47  in  FIG. 3 . The wall  46 , which is in spaced relationship with inwardly protruding part  44 , cooperates with part  44  to form and annular slot  48  which receives outwardly protruding annular part  40  of the ring  26 . Slot  48 , and corresponding similar slots (not shown) are disposed around the circumference of the core  14  at both ends thereof and fit the outwardly protruding annular parts  40  of the rings closely in order to secure the arc-shaped segments of the core firmly to the rings. Movement of annular parts  40  into the slots is limited by engagement between the outer perimeters of the annular parts with the bottoms of slots  48 . 
     As seen in  FIG. 1 , the protruding annular parts  40  of the ring are interrupted by two outwardly extending protrusions  50  located opposite each other on opposite sides of the ring. These protrusions extend into slots formed by notches  52  when the two parts of the core are brought together. The annular parts  40  of each ring are also interrupted by slots  54 , which receive locking parts  55  formed at both ends of each of the arc-shaped core segments  10  and  12 . 
     In the process of assembly of the reel, the wooden flanges, with rings  26  attached to them, are positioned so that their protruding annular parts  40  enter the slots  48  of the core parts  10  and  12  are brought together. The locking parts  55  on the core segments enter the slots  54  of the rings and secure the core parts to the rings in the manner depicted in  FIGS. 4 and 5 . 
     As shown in  FIG. 4 , a slot  54  of a ring includes a wall  56 , which is in abutting relationship with a wooden flange when the ring is attached to the flange. The locking member includes a hook-shaped arm  58  connected at one end  60  to an end of an outer wall of a core part  12 , and having an enlargement  62  at its opposite end that extends underneath wall  56  to lock the core part to the ring. The position of the part  64  of the enlargement  62  that extends underneath the inner end  64  of wall  56  is preferably such that, when the annular ring element  40  is in full engagement with the bottom of a slot  48  as shown in  FIG. 3 , only a very small clearance, e.g., around 1 mm, exists between part  62  and the inner end  64  of wall  56 . Preferably, the inner end  64  of wall  56  and the surface of the enlarged part  62  of the arm that engages the end of the wall are both disposed at an angle of about 10 E as shown in  FIGS. 4 and 5  so that the edge of the inner end of the wall closest to the flange  22  is slightly radially outward from the edge remote from the flange. These angled parts of the wall and the arm aid in preventing accidental unlatching. 
     The arm  58  is resilient, so that its enlarged part  62  snaps into place underneath the inner end  64  of the wall, thereby securely holding the core part and the ring in engagement with each other. A spacer  67  is formed on wall  56  adjacent the outer end thereof to maintain a spacing between the wall and the locking arm  58 . The enlarged part  62  of the locking arm is deflected by a ramp  66  on the front part of wall  56  as the core parts are brought out of engagement with the rings, so that the enlarged part  62  can clear spacer  67 . 
     As shown in  FIG. 5 , a hole  68  is provided in the flange, adjacent the inner end  64  of wall  56  and in register with the enlarged part  62  of the resilient arm  58 , to allow access to the arm so that the arm can be disengaged from the wall by pushing it manually, or by means of a tool. Thus, the core parts can be readily and easily disconnected from the rings and from each other for disassembly of the reel. 
     As shown in  FIG. 6 , the arc-shaped segment  12  has rows of tabs  16 , the tabs being in alternating relationship with slots  18 . The two core segments are preferably identical, and therefore capable of being produced in the same mold. 
     Each core segment is reinforced by an array  70  of ribs formed as parts of the inner surface of the core. Included in the reinforcing ribs is a central rib  72  which rigidly connect U-shaped parts  74  and  76  of the locking members at opposite ends of the core parts. The legs of part  74  are formed with rigid protrusions  78  and  80 , which are located in circumferentially spaced relationship to each other on opposite sides of locking arm  58 . These rigid protrusions extend beyond the inner end of locking arm  58 , and protect the locking arm from damage when the core segments are stacked one upon another for shipment after disassembly of the reel. The rigid protrusions  78  and  80  have outer edges  82  and  84 , which gradually become closer together proceeding radially inward toward the core axis. As shown in  FIG. 7 , a slot  54  in ring  26  has opposed sides  86  and  88 , which protrude from the wall  56  in spaced relationship to each other toward the opposite ring. These opposed sides are progressively closer to each other proceeding radially inward toward the axis, causing the slot to be tapered. The tapered relationship of sides  86  and  88  correspond to the tapered relationship between the outer edges of protrusions  78  and  80 , and the outer edges of the protrusions conform to and engage the opposed sides  86  and  88  of slot  54  when the outwardly facing surface of the locking arm  58  adjacent and between protrusions  78  and  80  is engaged with the inwardly facing end surface  64  of wall  56 . The matching tapered relationship of the protrusions and the sides of slot  54  helps to ensure that the core segments remain firmly attached to the rings when the locking elements are engaged. 
     The core segments and rings can be molded from any of a variety of materials. Suitable materials include polycarbonate resin, e.g., Sabic FL910 polycarbonate, and various glass fiber-reinforced polycarbonate resins. 
     In the alternative embodiment illustrated in  FIGS. 8 and 9 , the locking arm is composed of a rectangular strip  90  of sheet metal and a resin block  92  secured together by fasteners  94 . The sheet metal strip is sufficiently thin that it can be bent manually, and resilient so that it returns to its original condition when released after being bent. Any of a various kinds of sheet steel, suitably heat-treated, can be used for the sheet metal strip  90 , as can other metals having suitable spring characteristics. The resin block  92  can be molded from any suitable polymeric resin, including the resins mentioned above, and preferably has a shape similar to that of enlarged part  62  of arm  58  as shown in  FIGS. 4 and 5 . 
     As shown in  FIG. 9 , metal strip  90  is secured by fasteners  96  to an inwardly protruding flange  98  formed on arc-shaped core segment  12   a . If the metal strip is normally flat in its relaxed condition, the outer wall  100  of flange  98  should have a slight slope so that block  92  is positioned underneath wall  56   a  when the metal strip is relaxed. 
     The locking arm operates in the same manner as the integral locking arm in the previously described embodiment. The arm snaps into place when the core segment to which it is attached is slid into engagement with the ring fastened to a wood reel flange, and can be disengaged manually by being by a tool inserted through an access hole (not shown) in the reel flange. 
     An advantage of the alternative locking arm is that it avoids difficulties encountered in molding the locking arm as a unitary part of a core segment. Another advantage is that it can be stronger than the unitary resin arm, and yet easier to bend both in assembly and disassembly of the reel. 
     Still another alternative, not illustrated, is the use of a locking arm that is entirely composed of sheet metal, wherein the block for engaging the inner end of a locking wall on the ring consists of an extension of the metal strip suitably bent into the form of a latching block corresponding to block  92  in  FIGS. 8 and 9 . 
     Still other variations of the invention will become apparent to those skilled in the art, and can be adopted without departing from the scope of the invention as defined in the following claims.