Abstract:
A shackle assembly has a clip that is essentially permanently affixed to the overhead conveyor in a poultry processing plant and a shackle that can be attached to and detached from the clip without the use of hand tools. Significant motion of the shackle relative to the clip is permitted without promoting accidental detachment from the clip such that the shackles can be manipulated as need be by various guide structures and the like throughout their movement along the processing line and inspectors can move the suspended carcasses into the most advantageous positions for visual inspection. However, when detachment is desired, a locking head on the shackle that is loosely confined within a key slot in the clip can be oriented in such a way as to permit the shackle to be withdrawn from or replaced within the clip when the conveying line has been disengaged and stopped. Alternative embodiments are disclosed of both the clip and the shackle, including both metal and non-metal forms.

Description:
TECHNICAL FIELD  
         [0001]    The present invention relates to poultry processing equipment and, more particularly, to a shackle assembly in which the shackle is quickly and easily attachable to and removable from an overhead conveyor typically used in poultry processing plants. In a preferred form, the present invention also relates to improvements in a shackle that is constructed from synthetic resinous material.  
         BACKGROUND  
         [0002]    Many poultry shackles in current use are constructed from metal. The many guide rods and other structures engaged by the shackles as they travel along a conveying line in a processing plant are also largely metallic. Consequently, the shackles tend to clank and clatter throughout their travel, creating considerable noise. Moreover, conventional metal shackles can become bent and deformed during heavy use, which impairs their ability to properly hold and position carcasses as they are moving through the plant. Sometimes, the shackles may become jammed in the processing equipment and cause serious damage.  
           [0003]    Current all-metal systems do not provide for quick detachment and replacement of damaged metal shackles. Instead, hand tools must be utilized while considerable time is lost attending to the repair. While some plastic shackles are currently available in the marketplace, they are not fully satisfactory in all respects.  
           [0004]    One prior art assembly utilizes a metal clip that is essentially permanently secured to the conveyor such as by bolting. The shackle of the assembly has a specially configured projection at its upper end that fits into and is retained within a receiving slot in the clip, without the use of fasteners. The slot has a narrow supporting portion in the clip floor that keeps the enlarged, generally rectangular head of the projection from falling out of the clip when the shackle is hanging vertically during normal operating conditions, as well as an enlarged access portion in the clip sidewall remote from the narrow portion and through which the enlarged head can be intentionally inserted and removed. Unless the shackle is raised into a generally horizontal orientation and rotated into such a position that the enlarged rectangular head is generally in line with the slot, the head cannot be passed through the access portion, thus making accidental disconnection of the shackle from the clip highly unlikely. A cylindrical neck immediately below the retaining head permits the shackle to be freely rotated about its longitudinal axis.  
         SUMMARY OF THE INVENTION  
         [0005]    The present invention addresses the problems of the prior art by providing an improved shackle assembly. In one preferred embodiment, the prior art metal clip is still used, but the shackle is different. One preferred form of the shackle interposes a transverse anti-rotation bar immediately below the retaining head that is normally disposed at slot level so as to engage internal side edges of the slot when rotation is attempted. To rotate the shackle, such as for installation and removal or carcass inspection, the shackle is raised until the neck is at slot level and the anti-rotation bar is positioned above the slot, whereupon rotation is no longer impeded. If desired, the anti-rotation bar may be provided with tapered opposite ends so as to permit a limited amount of rotation of the shackle in either direction about its longitudinal axis without raising the shackle, thus accommodating the slight, normal twisting and turning movements from side-to-side that are necessary during processing operations. In-and-out swinging movement of the shackle is also permitted.  
           [0006]    In another preferred form of shackle, the rectangular locking head of the prior art shackle has been replaced with a generally oval-shaped head to improve the ease with which the shackle may be intentionally rotated within the clip during processing operations. The oval-headed shackle may or may not be provided with an anti-rotation locking bar.  
           [0007]    The clip may comprise the prior art metal clip, or it may be constructed from a suitable synthetic resinous material. If metal is used, the clip may be fabricated from sheet metal by cutting, punching, and forming a piece into the desired shape. When completed, the sheet metal piece assumes a generally L-shaped configuration with a normally upright sidewall and a cantilevered, normally horizontally extending floor that projects out laterally from the sidewall. A hole for use in attaching the clip to the conveyor with a bolt is located at the normally upper end of the sidewall. The narrow portion of the slot runs across the floor and partially up the sidewall, where it intersects with the enlarged, access portion. The distal end of the floor is upturned to form a short, second sidewall for strength.  
           [0008]    If the clip is constructed from a synthetic resinous material such as Nylon, it is preferred that the clip be formed symmetrically and generally U-shaped, with a pair of mirror image sidewalls that are interconnected by a common, transverse floor. The upper ends of the sidewalls are provided with a pair of aligned holes for receiving a common attaching bolt. The narrow portion of the slot extends across the floor and partially up the opposite sidewalls, where it intersects an enlarged access portion in each sidewall.  
           [0009]    The shackle may be metal or synthetic resinous material such as Nylon. If constructed from metal, the crosshead of the attaching connection is long enough, compared to the width of the floor between sidewalls of the clip, to strike the sidewalls after a certain amount of limited, free rotation of the shackle about its longitudinal axis. If the shackle is constructed from synthetic resinous material, its integral body is formed into three main sections, i.e., a central shank, a connecting projection at the upper end of the shank, and a hock-engaging retainer at the lower end of the shank in the nature of a pair of leg loops disposed in a common plane. The shank is preferably rectangular in transverse cross-section, while the leg loops have cylindrical limbs that are circular in transverse cross-section. The limbs can yield and bend to a certain extent without becoming permanently deformed, but if subjected to excessive external force will break apart so as to prevent damage to whatever structure or mechanism maybe applying the bending force to the shackle, whereupon the broken shackle can be discarded and replaced by a new one. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    [0010]FIG. 1 is a fragmentary, front elevational view of a poultry carcass conveyor line incorporating shackle assemblies constructed in accordance with the principles of the present invention, the phantom lines indicating poultry carcasses hanging from the shackle assemblies;  
         [0011]    [0011]FIG. 2 is a side elevational view of one of the shackle assemblies and carcass, with portions of the conveyor being shown in cross-section;  
         [0012]    [0012]FIG. 3 is an enlarged, fragmentary isometric view of a prior art shackle assembly;  
         [0013]    [0013]FIG. 4 is an enlarged, fragmentary, exploded isometric view of one embodiment of the invention using a prior art clip;  
         [0014]    [0014]FIG. 5 is an enlarged front elevational view of the prior art clip with a front corner thereof broken away to reveal details of construction;  
         [0015]    [0015]FIG. 6 is a vertical cross-sectional view of the prior art clip taken substantially along line  6 - 6  of FIG. 5;  
         [0016]    [0016]FIG. 7 is a horizontal cross-sectional view of the prior art clip taken substantially along line  7 - 7  of FIG. 5;  
         [0017]    [0017]FIG. 8 is an enlarged, fragmentary front elevational view of the shackle assembly of FIG. 4, the phantom lines illustrating how the shackle can rock side-to-side within the clip;  
         [0018]    [0018]FIG. 9 is a vertical cross-sectional view of the shackle assembly of FIG. 4 taken substantially along line  9 - 9  of FIG. 8, the phantom lines illustrating how the shackle can swing in-and-out within the clip;  
         [0019]    [0019]FIG. 10 is a horizontal cross-sectional view taken substantially along line  10 - 10  of FIG. 8;  
         [0020]    [0020]FIG. 11 is a horizontal cross-sectional view taken substantially along line  11 - 11  of FIG. 8, illustrating the manner in which the shackle is free to experience limited rotation about its longitudinal axis to the extent permitted by an anti-rotation bar immediately below the head of the shackle;  
         [0021]    [0021]FIG. 12 is a fragmentary isometric view of the shackle assembly of FIG. 4 with a front comer of the clip broken away to illustrate the manner in which the retaining head of the shackle normally sits transversely across the slot in the clip;  
         [0022]    [0022]FIG. 13 is a front elevational view of a prior art shackle assembly in which both the clip and shackle are constructed in accordance with the teachings of the prior art, the shackle being devoid of an anti-rotation bar, and phantom lines illustrating the manner in which the shackle can swing from side-to-side;  
         [0023]    [0023]FIG. 14 is a vertical cross-sectional view of the prior art shackle assembly of FIG. 13 taken substantially along line  14 - 14  of FIG. 13;  
         [0024]    [0024]FIG. 15 is a fragmentary isometric view of another embodiment of shackle assembly (using the prior art clip) in which the shackle is constructed from metal and is free to rotate about its longitudinal axis within the limits determined by the opposite ends of the cross head striking the sidewalls of the clip;  
         [0025]    [0025]FIG. 16 is a front elevational view of the FIG. 15 embodiment with parts broken away and shown in cross-section for clarity, the phantom lines illustrating the manner in which the shackle can swing from side-to-side;  
         [0026]    [0026]FIG. 17 is a vertical cross-sectional view of the FIG. 15 embodiment taken substantially along line  17 - 17  of FIG. 16, the phantom lines illustrating the manner in which the shackle can swing in and out;  
         [0027]    [0027]FIG. 18 is a horizontal cross-sectional view of the FIG. 15 embodiment taken substantially along line  18 - 18  of FIG. 16, the phantom lines illustrating the manner in which the shackle is free to rotate to a limited extent about its longitudinal axis;  
         [0028]    [0028]FIG. 19 is a fragmentary, exploded isometric view of another embodiment of shackle assembly in which a molded synthetic resinous clip is utilized;  
         [0029]    [0029]FIG. 20 is an enlarged, front elevational view of the clip of the FIG. 19 embodiment;  
         [0030]    [0030]FIG. 21 is a vertical cross-sectional view thereof taken substantially along line  21 - 21  of FIG. 20;  
         [0031]    [0031]FIG. 22 is a top plan view of the clip of the FIG. 19 embodiment taken substantially along line  22 - 22  of FIG. 20;  
         [0032]    [0032]FIG. 23 is a front elevational view of the shackle assembly of the FIG. 19 embodiment with parts broken away and shown in cross-section for clarity, the phantom lines illustrating the manner in which the shackle can swing from side-to-side;  
         [0033]    [0033]FIG. 24 is a vertical cross-sectional view of the FIG. 19 embodiment taken substantially along line  24 - 24  of FIG. 23, the phantom lines illustrating the manner in which the shackle can swing in and out;  
         [0034]    [0034]FIG. 25 is a horizontal cross-section view of the FIG. 19 embodiment taken substantially along line  25 - 25  of FIG. 23, the phantom lines illustrating the manner in which the shackle is free to experience limited rotation about its longitudinal axis;  
         [0035]    [0035]FIG. 26 is a fragmentary, exploded isometric view of a further embodiment of shackle assembly (using the prior art clip) wherein the shackle has an oval-shaped head and an anti-rotation bar beneath the head;  
         [0036]    [0036]FIG. 27 is a front elevational view of the FIG. 26 embodiment with the upturned front portion of the clip broken away and the shackle swung upwardly and rearwardly to illustrate that the length dimension of the oval head exceeds the width of the entry slot;  
         [0037]    [0037]FIG. 28 is a top plan view of the FIG. 26 embodiment with the rear sidewall of the clip broken away, a rotated position of the shackle head being illustrated by phantom lines;  
         [0038]    [0038]FIG. 29 is a fragmentary, exploded isometric view of another embodiment of shackle assembly (using the prior art clip) wherein the shackle has an oval-shaped head but no anti-rotation bar beneath the head;  
         [0039]    [0039]FIG. 30 is a front elevational view of the FIG. 29 embodiment with the upturned front portion of the clip broken away and the shackle swung upwardly and rearwardly to illustrate that the length dimension of the oval head exceeds the width of the entry slot; and  
         [0040]    [0040]FIG. 31 is a top plan view of the FIG. 29 embodiment with the rear sidewall of the clip broken away, a rotated position of the shackle head being illustrated by phantom lines. 
     
    
     DETAILED DESCRIPTION  
       [0041]    [0041]FIGS. 1 and 2 illustrate an overhead conveyor  10  utilizing shackle assemblies  12  in accordance with the present invention to transport poultry carcasses  14  through a processing plant. As well understood by those skilled in the art, conveyor  10  includes a track  16  having series of trollies  18  hanging therefrom for travel therealong, the trollies  18  being interconnected by a link chain  20 . Each trolley  18  has a hanger  22  projecting downwardly therefrom, there also being a hanger  22  supported from the chain  20  between each pair of trollies  18 .  
         [0042]    Each shackle assembly  12  has two main parts, i.e., a prior art clip  24  essentially permanently fastened to the hanger  22 , and a shackle  26  that is detachably secured to the clip  24  without the use of fasteners. Dealing first with the prior art clip  24 , it will be seen from the detail views in FIGS.  4 - 7  that the clip is generally L-shaped in side elevation, having an upright sidewall  28  and a normally horizontally extending floor  30  projecting outwardly from the sidewall  28 . Floor  30  is upturned at its end remote from the sidewall  28  so as to present a short second sidewall  32  spaced laterally outwardly from the first sidewall  28 . Floor  30  and short sidewall  32  are cantilevered from the sidewall  28 .  
         [0043]    Clip  24  has a key slot  34  therein that is closed at its opposite ends and that extends generally axially of the longitudinal axis of the clip. Slot  34  includes a narrow portion  36  that runs along the floor  30  and up the sidewall  28  until intersecting with an enlarged, rectangular access portion  38  of slot  34 . At its other end, the narrow portion  36  extends up the sidewall  32  for a short distance. A mounting hole  40  is located in sidewall  28  adjacent the upper end thereof and above the enlarged portion  38 . Hole  40  is adapted to receive a bolt assembly  42  for essentially permanently fastening clip  24  to hanger  22 . In its preferred form, clip  24  is cut from a piece of sheet metal, is punched to form the key slot  34 , and is bent to assume the general L-shaped configuration with the two sidewalls  28  and  32 .  
         [0044]    In the illustrated embodiment, the shackle  26  comprises a unitary body of synthetic resinous material, for example, Nylon  6 . Shackle  26  comprises three major portions or sections, i.e., a central elongated shank  44 , a connector  46  at the upper end of shank  44 , and a leg-engaging retainer  48  at the lower end of shank  44  (which may hold the birds either by their hocks or their feet). Retainer  48  has a pair of leg loops  50 , 52  that receive and retain the hocks of the carcass  14  so that the carcass  14  is suspended in an inverted position as illustrated in FIGS. 1 and 2. Each leg loop  50 , 52  includes a pair of inner and outer limbs  54  and  56  respectively that are of substantially circular cross-sectional configuration. Limbs  50  and  56  can flex and bend without being permanently deformed due to their synthetic resinous construction. The cross-sectional diameter of limbs  54 , 56  is such that, taking into account the material from which they are fabricated, limbs  54  and  56  can break under the application of sufficient bending force thereto, such breakage occurring in lieu of the limbs taking any permanent deformation. As noted particularly in FIG. 2, leg loops  50 , 52 , lie in a common plane.  
         [0045]    Shank  44  of shackle  26  is rectangular in transverse cross-sectional configuration, presenting four flat sides  58  that maybe described as a front side  58   a,  a left side  58   b,  a back side  58   c,  and a right side  58   d.  Front and back sides  58   a,   58   b  are parallel to the plane of the leg loops  52 , while left and right sides  58   b,   58   d  are perpendicular to the plane of leg loops  50 , 52 . Flat-sided shank  44  transitions into the rounded limbs  54 , 56  of retainer  48  at the bottom end of shank  44 . A central generally flat stiffening strut  60  in the retainer  48  extends vertically in essentially axial alignment with the shank  44  and connects with the outer limbs  56  at their upper ends and the shorter inner limbs  54  at their upper ends.  
         [0046]    The connector  46  of shackle  26  is in the nature of a generally T-shaped projection having an axially disposed, cylindrical neck  62  of circular cross-sectional configuration and a cross-head  64  extending transversely of the neck  62  across its upper end. Head  64  is symmetrically disposed upon the neck  62 , projecting in opposite directions therefrom to an equal extent. Head  64  is elongated in a direction parallel to the plane of the leg loops  50 , 52 , as well as parallel to the plane of the front and back sides  58   a,   58   c  of shank  44 . Head  64  has a pair of opposite, rounded ends  66 ,  68 , as well as a pair of opposite straight sides  70 , 72 . Head  64  is both longer and wider than the width of the narrow portion  36  of slot  34 . On the other hand, while head  64  is slightly longer than the vertical dimension of the enlarged access portion  38 , it is slightly narrower than the width dimension of enlarged portion  38 . The length dimension of head  64  is measured between the opposite rounded ends  66 , 68 , while the width dimension is measured between the opposite flat sides  70 , 72 .  
         [0047]    In the illustrated embodiment, the connector  46  of shackle  26  further includes an anti-rotation bar  74  immediately below the head  64  and above the neck  62 . As shown particularly in FIGS.  8 - 12 , neck  62  is slightly smaller in diameter than the width of the narrow portion  36  of slot  34 . Likewise, anti-rotation bar  74  has a width dimension that essentially corresponds with the diameter of neck  62  such that bar  74  is flush with neck  62  essentially in the mid-section of bar  74  such that bar  74  is received within the narrow portion  36  of the slot when bar  74  is disposed in alignment with slot  34 . On the other hand, the longitudinal dimension of the bar  74  is substantially greater than the width of the narrow slot portion  36 , the bar  74  terminating at its opposite ends substantially flush with the flat sides  70 , 72  of head  64 . The opposite ends of bar  74  are preferably tapered so as to present converging faces  76 , such tapering configuration thus permitting a limited degree of axial rotation of shackle  26  when bar  74  is disposed within narrow slot portion  36  as illustrated in FIG. 11, for example. Such limited rotation is on the order of 15° degrees in each direction. As is apparent, bar  74  is elongated in a direction perpendicularly transverse to the direction of elongation of head  64  such that the longitudinal axis of bar  74  is perpendicular to the common plane of the leg loops  50 , 52 . A circular collar  78  at the base of neck  62  is spaced below bar  74  and substantially exceeds the width dimensions of slot  34 . Except for the presence of anti-rotation bar  74 , shackle  26  is identical to prior art shackle  126  of FIGS. 13 and 14.  
         [0048]    Operation  
         [0049]    In use, the shackles  26  are suspended from the clips  24  for movement along a processing line defined generally by the conveyor  10 . Poultry carcasses  14  are suspended by their hocks from the leg loops  50 , 52  of shackles  46  so that various processing and inspection operations can be carried out thereon. Shackles  26  are suspended by their loose interconnections with the clips  24  via the slots  34  in clips  24  and the connectors  46  on shackles  26 . At this time, anti-rotation bars  74  are received within the narrow slot portions  36 , while the heads  64  are disposed transversely of and overlie narrow slot portions  36  as illustrated in FIG. 12.  
         [0050]    With the upper ends of the shackles  26  loosely connected to the clips  24  in this manner, shackles  26  are free to swing from side-to-side to a limited extent as illustrated, for example, in FIG. 8. Similarly, they are free to swing in and out to a limited extent as illustrated in FIG. 9. Furthermore, although anti-rotation bar  74  on each shackle is intended to prevent free rotation of the shackle about its longitudinal axis, the tapered ends of each bar  74  permit a small amount of axial rotation of each shackle, on the order of 15 degrees or so in each rotative direction, as illustrated in FIG. 11.  
         [0051]    Such freedom of movement at the point of connection between shackle  26  and clip  24  is helpful and important as the carcasses travel throughout the processing plant. For example, during inspection of the carcasses at various locations, it is necessary for the inspector to be able to grab the moving carcass and manipulate it in the manner necessary to carry out the inspections. Further, the shackles frequently need to move around bends, be swung in and out, and be hanging at an angle relative to the clips as the shackles are engaged by various guiding structures and are subjected to the force of gravity while the trollies  18  remain in generally fixed attitudes relative to the track  16 .  
         [0052]    The flats on the various faces of shank  44  are helpful in maintaining the carcasses  14  properly oriented as the shackles engage guide rods and other structures throughout the processing operations. Thus, the flat sides of shank  44  help prevent unintended rotation of the carcasses during travel and manipulation. Of course, the anti-rotation bars  74  provide the primary means of protection against rotation, but the flat shank sides are helpful in this respect as well and take some of the load off the surfaces of the bar  74 .  
         [0053]    In the event that there is a need to intentionally rotate the carcasses more than the limited amount of rotation provided by the tapered ends of the anti-rotation bar  74 , the shackle to be rotated simply needs to be grasped and pushed upwardly a sufficient distance as to dispose bar  74  above narrow slot portion  36  and neck  62  within such portion. Normally, this position will be established when the lower limit collar  78  butts up against the bottom of the floor  30 . With the anti-rotation bar  74  thus cleared from narrow slot portion  36 , shackle  26  can be freely rotated to any desired position, it being noted that the length of head  64  is slightly less than the distance between the opposite sidewalls  28 , 32  such that the sidewalls do not interfere with head  64  during such rotation. When it is desired to lock shackle  26  back in an orientation that precludes substantial rotation, it is only necessary to realign the bar  74  with narrow slot portion  36  and allow shackle  26  to drop down slightly until head  64  engages clip floor  30 .  
         [0054]    In the event that a shackle becomes broken or removal is desired for any other reason, such can be quickly and easily accomplished without the use of hand tools and without manipulating any fasteners. First, the conveyor line  10  is disengaged so that it is no longer moving. Then, it is only necessary to grasp the shackle  26  and swing it upwardly and rearwardly generally in the manner illustrated in FIG. 4 until head  64  is within enlarged portion  38 , whereupon shackle  26  maybe freely rotated because of the excessive width dimension of enlarged portion  38  relative to the length dimension of anti-rotation bar  74 . Once shackle  26  has been rotated  90 ° degrees about its longitudinal axis so as to generally align head  64  with the longitudinal axis of slot  34 , shackle  26  may be angled upwardly or downwardly to a sufficient extent as to cause one or the other of the rounded ends  66 , 68  of head  64  to slip angularly through the enlarged portion  38 . Once one end of head  64  starts angularly through enlarged slot portion  38 , the rest of head  64  can be brought easily out of portion  38  until the shackle  26  is entirely disconnected from clip  24 .  
         [0055]    Replacement of the damaged shackle with a new shackle is equally simple. By orienting the shackle in the manner illustrated in FIG. 4, head  64  is generally aligned with slot  34 . Since enlarged portion  38  is slightly shorter than the overall length of head  64 , head  64  must be somewhat inclined as illustrated in FIG. 4 in order for one or the other of the opposite ends  66 , 68  to enter portion  38 . Once an end such as lower end  66  in the FIG. 4 illustration has entered and passed substantially through the enlarged slot portion  38 , the shackle can be brought up to a substantially horizontal position and head  64  pushed completely through enlarged slot portion  38  until it is disposed on the front side of sidewall  28 . Thereupon, rotation of the shackle  90 ° about its longitudinal axis causes anti-rotation bar  74  to become aligned with slot  34  and head  64  to be disposed transverse thereto, whereupon shackle  26  can be brought down into a vertical hanging disposition as illustrated in FIG. 12 wherein head  64  transversely overlies and spans narrow slot  36  and bears against floor  30  to support the weight of the rest of the shackle and the carcass  14 .  
         [0056]    Other Embodiments  
         [0057]    The embodiment illustrated in FIGS.  15 - 18  is a shackle assembly  212  that is especially well-suited for a metal shackle  226 . Clip  224  is identical to the prior art metal clip previously described, but shackle  226  differs from shackles  26  and  126 , in part because it is constructed from metal. In the embodiment of FIGS.  15 - 18 , shank  244  is cylindrical so as to be circular in cross-sectional configuration. The connector projection  246  remains generally T-shaped, but cross head  264  is likewise cylindrical and is the same diameter as shank  244  and neck  262 . No anti-rotation bar is provided between head  264  and neck  262 , but head  264  is preferably of such a length that its opposite ends strike sidewalls  228  and  232  of clip  224  when rotation of shackle  226  about is longitudinal axis is attempted, as illustrated in FIG. 18. Due to the narrowness of head  264  relative to the space between front and rear sidewalls  232  and  228 , shackle  226  can experience a limited amount of rotation about its longitudinal axis before head  264  engages sidewalls  228 , 232 .  
         [0058]    Removal of shackle  226  from clip  224  is carried out in essentially the same manner as in the earlier embodiments, i.e., after swinging shackle  226  backwardly and upwardly into an essentially horizontal position, the shackle may be rotated about its longitudinal axis to dispose head  264  essentially in line with slot  234 . Then, head  264  maybe simply slipped through slot  234  to disengage shackle  226 , since the diameter of head  264  is less than the width of slot  234 , even in the narrow slot portion  236 . Replacement of shackle  226  is a simple reversal of this process. It will be apparent that due to the nature of head  264 , it is not necessary for slot  234  to have an enlarged portion  238 , although such an arrangement permits the same style of clip to be used with any of the herein disclosed styles of shackles. As noted in FIGS. 16 and 17, shackle  226  can also be swung from side-to-side and in and out.  
         [0059]    FIGS.  19 - 25  illustrate another shackle assembly  312  in which shackle  326  is identical to shackle  26  but clip  324  is different. The primary difference with respect to clip  324  is that, like shackle  326 , clip  324  is most advantageously constructed from synthetic resinous material such as Nylon  6 . Due to the lack of overall strength, however, of synthetic resinous material as compared to metal, clip  324  is generally transversely U-shaped, instead of L-shaped, such that both front and rear sidewalls thereof are adapted to be attached to the hanger  22  instead of only the rear sidewall  28  as in the earlier embodiments.  
         [0060]    In clip  324 , both front sidewall  332  and rear sidewall  328  are provided with attaching holes  340  adjacent their upper ends for receiving the bolt assembly  42  associated with hanger  22 . Thus, in clip  324 , the hanger  22  is sandwiched between the front and rear sidewalls  332  and  328  so that both sidewalls support the load of the shackle  326  and the carcass.  
         [0061]    It will be noted that sidewalls  328 , 332  are mirror images of one another such that they correspond in height to one another. Further, it will be noted that the slot  334  has a pair of enlarged portions  338  at its opposite closed ends, instead of only a single enlargement as in previous embodiments. Thus, in the embodiment of FIGS.  19 - 25 , the narrow portion  336  of slot  334  runs across the entire width of floor  330  and up the opposite sidewalls  328 ,  332  until intersecting with the enlarged portions  338  approximately halfway up sidewalls  328 , 332 .  
         [0062]    As a result of the double access openings in clip  324  provided by enlargements of  338 , shackle  326  may be attached and detached from clip  324  from either the front or the back. In either case, the method of removal and reinsertion of the head  364  of shackle  326  is essentially the same as that described above with respect to shackle  26  and clip  24 . It will also be noted that shackle  326  is free to move to a limited extent from side-to-side as illustrated in FIG. 3, and from front to rear as illustrated in FIG. 24. Additionally, shackle  326  can rotate to a limited extent about its longitudinal axis as illustrated in FIG. 25.  
         [0063]    FIGS.  26 - 28  illustrate an additional embodiment of shackle assembly designated by the numeral  512 . Shackle assembly  512  is identical to assembly  12 , except for the shape of head  564 . Whereas in the earlier embodiment the head of the projection was generally rectangular as viewed in plan, head  564  is generally oval as viewed in plan. Head  564  has its longitudinal axis extending generally parallel to the common plane of the leg loops (not shown) of the shackle  526 , with the anti-rotation bar  574  extending transversely of the common plane of the leg loops.  
         [0064]    Head  564  has arcuate side edges  570  and  572 , as well as arcuate opposite ends  566  and  568  of smaller radius than side edges  570 , 572 . Bar  574  terminates at its opposite ends substantially flush with arcuate side edges  570  and  572 . Neck  562  is of such diameter as to be freely rotatable within slot  534  of clip  524  when shackle  526  is lifted upwardly to such an extent as to raise bar  574  out of slot  534 .  
         [0065]    As illustrated in FIG. 27, the oval head  574  has a length dimension that slightly exceeds the width of enlarged portion  538  of slot  534  in clip  524 . Thus, even if shackle  526  is swung upwardly and rearwardly into a substantially horizontal position as illustrated in FIG. 27, head  564  continues to overlap enlarged portion  538  to discourage accidental release of shackle  526  from slot  534 . However, by slightly cocking or twisting shackle  526  when it is in this position, head  564  may be slipped through enlarged portion  538  even without rotating shackle  526  90°.  
         [0066]    The width dimension of head  564  between side edges  570  and  572  is slightly less than the width of enlarged portion  538 . Consequently, if shackle  526  is rotated 90° from its FIG. 27 position, head  564  can be pulled rearwardly straight through enlarged portion  538  without twisting cocking shackle  526 .  
         [0067]    It will also be seen from FIG. 28 that the length dimension of head  564  between opposite ends  566  and  568  is significantly larger than the width of the narrow portion  536  of slot  534 . Furthermore, the width dimension of head  564  between side edges  570  and  572  is somewhat greater than the width of narrow slot portion  536 . The length dimension of head  564  between opposite end edges  566  and  568  is somewhat less than the distance between sidewalls  528  and  532  of clip  524  so that head  564  does not interfere with free rotation of shackle  526  when anti-rotation bar  574  is up out of slot  534  and neck  562  is aligned with slot  534 .  
         [0068]    FIGS.  29 - 31  illustrate a further embodiment of shackle assembly denoted by the numeral  612 . In this embodiment, shackle assembly  612  is identical to shackle assembly  512  except that no anti-rotation bar is provided. Thus, neck  662  of shackle  626  extends up into intersection with the bottom of oval shaped head  664  without the presence of an anti-rotation bar immediately below head  664 . Shackle  626  is thus free to rotate at all times within slot  634  of clip  624 .  
         [0069]    Prior Art Constructions  
         [0070]    [0070]FIG. 3 illustrates a prior art shackle assembly attached to the hanger  22  of the conveyor by means of the bolt assembly  42 . The prior art shackle assembly has a generally L-shaped metal clip  400  that supports a metal shackle  402 . Shackle  402  is permanently affixed to clip  400  such that it cannot be removed from the conveyor unless clip  400  is unbolted from hanger  22  using hand tools. The cylindrical shank of shackle  42  passes loosely through an enlarged hole  404  in the horizontal leg of clip  400 , and a retaining washer  406  is welded to the uppermost end of the shackle. A lower stop collar  408  is welded to the shackle a distance below washer  406  so that a limited amount of vertical motion of the shackle is permitted. In view of the cylindrical nature of the shackle and the enlarged dimensions of the hole  404  compared thereto, shackle  402  is free to rotate within hole  404 .  
         [0071]    [0071]FIGS. 13 and 14 illustrate a prior art shackle assembly which is identical to assembly  12 , except that shackle  26  of assembly  12  is provided with the anti-rotation bar  74  while the prior art assembly, denoted by the numeral  112 , has none. Thus, neck  162  of shackle  126  extends completely up to and intersects with the bottom of head  164  such that shackle  126  is free to rotate at all times about its longitudinal axis within slot  134  of clip  124 . All other motions of shackle  126 , as illustrated in FIGS. 13 and 14, are the same as those permitted with shackle assembly  12 .  
         [0072]    Although preferred forms of the invention have been described above, it is to be recognized that such disclosure is by way of illustration only, and should not be utilized in a limiting sense in interpreting the scope of the present invention. Obvious modifications to the exemplary embodiments, as hereinabove set forth, could be readily made by those skilled in the art without departing from the spirit of the present invention.  
         [0073]    The inventors hereby state their intent to rely on the Doctrine of Equivalents to determine and assess the reasonably fair scope of their invention as pertains to any apparatus not materially departing from but outside the literal scope of the invention as set out in the following claims.