Abstract:
A field replaceable buckle with reinstallable cross bar includes at least one buckle part having a pair of lateral lugs extending therefrom. Each lateral lug has at least one aperture provided therein. The reinstallable cross bar includes a securing portion and a retaining portion. When the reinstallable cross bar is inserted through an aperture in a first lateral lug, it is prevented from passing therethrough by the retaining portion and the securing portion is operable to securely, but releasably, engage an aperture in the second lateral lug.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention relates to a field replaceable cross bar for buckles. The invention is particularly suited to side release buckles consisting of one male and one female component which are releasably lockable together, and where webbing is looped around a single cross bar provided in the proximate end of at least one of the components. 
       BACKGROUND 
       [0002]    The following discussion of the background to the invention is intended to facilitate an understanding of the present invention. However, it should be appreciated that the discussion is not an acknowledgment or admission that any of the material referred to was published, known or part of the common general knowledge in any jurisdiction as at the priority date of the application. 
         [0003]    A side release buckle as described in U.S. Pat. No. 5,794,316 assigned to National Moulding Corp. is an example of a fastening device common to the art. The most common use of this type of buckle is to fasten together two entities by way of webbing or straps. In such a configuration, the buckle typically consists of two components—a female socket part and a male plug part. Furthermore, each of these parts typically consists of two sections:
       an engaging section at a distal end; and   an attachment section at a proximal end; and       
 
         [0006]    The engaging section typically incorporates the mating component to allow the two parts to securely connect in a releasable manner. The attachment section generally comprises a slot and cross bar arrangement for attaching the webbing or strap. 
         [0007]    In some configurations, the webbing or strap is threaded through a slot to form a loop around a cross bar and then fixed on to itself through stitching or other form of securing mechanism (for example, a rivet). The portion of the webbing or strap that encapsulates the cross bar is hereafter referred to as the capturing loop. 
         [0008]    A similar capturing loop is formed in buckles that commonly employ what is known in the art as a ladder lock configuration. Such buckles comprise a single component and is fixedly attached to one entity by means of a capturing loop formed around one cross bar. The buckle is then adjustably attached to a second entity by way of webbing alone. This adjustable attachment is achieved by virtue of the path the webbing takes as it is threaded around one or more other components of the buckle. 
         [0009]    There are two problems with these structures. Firstly, during production of side release buckles of the first configuration type, the minimum width of the sewing foot of the sewing machine does not allow the stitching to be executed very close to the captured cross bar. This leaves the capturing loop loose around the cross bar. The freedom of movement resulting from this loose fitting is not desirable in some applications where the webbing must remain proud and resist twisting away from the plane of the webbing. 
         [0010]    The second problem with these structures is that these buckles, whether of the first or second configuration described, are typically formed from moulded plastic. This plastic is prone to break with extended use or in the case of accidental impact. When broken, as the cross bar forms an integral part of a mating component, there is no way to fix the buckle connection unless the stitching or other securing mechanism is reversed and the webbing re-threaded about the replacement buckle. This often cannot be achieved in a field situation or without the aid of specialised machines or tools. 
         [0011]    This problem is further exacerbated when it is considered that such buckles are extensively used in equipment for outdoor and adventure sports and the whole article can be rendered useless or sub-par if a buckle does not work properly. This can also have serious consequences for the user. 
         [0012]    It is therefore an object of the present invention to provide a field replaceable buckle with reinstallable cross bar and thus overcome the aforementioned problems. 
       SUMMARY 
       [0013]    Throughout this document, unless otherwise indicated to the contrary, the terms “comprising”, “consisting of”, and the like, are to be construed as non-exhaustive, or in other words, as meaning “including, but not limited to”. 
         [0014]    In accordance with a first aspect of the present invention there is a field replaceable buckle with reinstallable cross bar for a buckle, where the buckle comprises at least one buckle part having a pair of lateral lugs extending therefrom and each lateral lug has at least one aperture provided therein and where the reinstallable cross bar includes a securing portion and a retaining portion, such that when the reinstallable cross bar is inserted through an aperture in a first lateral lug it is prevented from passing therethrough by the retaining portion and the securing portion is operable to securely, but releasably, engage an aperture in the second lateral lug. 
         [0015]    Preferably, the aperture in the second lateral lug has a depth and the securing portion has a substantially corresponding length. 
         [0016]    The securing portion may take the form of a self tapping threaded end. The self tapping threaded end ideally cuts into side walls of the aperture in the second lateral lug as it is received therein by the application of rotational force. 
         [0017]    Alternatively:
       the securing portion is magnetised to a first polarity and the aperture in the second lateral lug is magnetised to a second polarity such that the securing portion is retained within the second lateral lug through magnetic forces.   the securing portion takes the form of a notch and the aperture in the second lateral lug incorporates a spring loaded latch, the spring loaded latch biased to engage the notch when the securing portion is received within the second lateral lug   the securing portion takes the form of a bolt stud adapted to be securely received within a nut positioned adjacent the aperture in the second lateral lug in such a manner as to ensure at least a portion of the cross bar is securely retained within the second lateral lug.       
 
         [0021]    The retaining portion may incorporate a depressed slot to facilitate the imparting of rotational force to the securing portion. 
         [0022]    Preferably, when received within the apertures, the reinstallable cross bar is sufficiently spaced from the buckle part to allow at least a portion of a capturing loop to be received therethrough. 
         [0023]    The reinstallable cross bar may further comprise a shaft portion interposed between the retaining portion and the securing portion, the shaft portion having a smooth surface. 
         [0024]    In an alternate configuration, the aperture in the first lateral lug has a matching shape and dimension to the shape and dimension of the retaining portion so as to ensure that the retaining portion is flush with an outer surface of the first lateral lug when received therein. 
         [0025]    The reinstallable cross bar may be made from stainless steel. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]    The invention will now be described, by way of example only, with reference to the accompanying drawings, in which: 
           [0027]      FIG. 1  is an exploded view of a buckle incorporating the present invention. 
           [0028]      FIG. 2  is a plan view of the buckle shown in  FIG. 1  as installed in capturing loops and as engaged. 
       
    
    
     DETAILED DESCRIPTION 
       [0029]    In accordance with a first embodiment of the invention there is a buckle  1  comprising a male prong part  2  and a female socket part  3 . Each of the male prong part  2  and female socket part  3  also incorporates a cross bar  4 . 
         [0030]    The male prong part  2  and female prong part  3  are moulded from Polyoxymethylene. 
         [0031]    The male prong part  2  consists of two lateral prongs  12  and a central spine  13 . The lateral prongs  12  have a spring cantilevered stem portion  14  terminating in a bulbous end  15 . The bulbous end  15  contains a shoulder with a “U”-shaped engaging surface  16 . The “U”-shaped engaging surface  16  locks against a similar “U”-shaped wall surface  17  on a lateral aperture  10  of the female socket part  3 . This locking arrangement is primarily a result of the dimensional overlap caused when the male prong part  2  is inserted into the female socket part  3 . 
         [0032]    The central spine  13  is located between the two lateral prongs  12 . Provided within the central spine  13  are longitudinal channels  18 . The longitudinal channels  18  are disposed on opposite faces  19  to correspond to central ribs  8  contained inside cavity  6  of the female socket part  3 . To elaborate, the central ribs  8  slide inside the longitudinal channels  18  when the male prong part  2  is inserted into the female socket part  3 . This ensures a symmetrical engagement in a straight line between the male prong part  2  and female prong part  3 . 
         [0033]    The female socket part  3  consists of a cavity  6  in the main body  5 . The cavity  6  has an engaging opening  7  at its distal end  6  in a well known configuration. The cavity  6  contains two central ribs  8  on opposing inside faces  9 . The cavity  6  also has lateral apertures  10 , in the form of two secondary openings, on side walls  30 . 
         [0034]    A pair of lateral lugs  11  are provided in the respective proximal ends  31 ,  32  of male plug part  2  and female socket part  3 . Each pair of lateral lugs  11  are designed to accommodate a buckle pin which acts as a single cross bar  4  for a capturing loop  20  of the webbing  21 . 
         [0035]    To accommodate the cross bar, one of the lateral lugs  11   a  has a through countersunk hole  22  provided therein. The countersunk hole  22  is sized to fit a screw head  23  of the cross bar  4 . The other lateral lug  11   b  contains an opposing hole  24  sized to enable a self tapping threaded end  25  of the cross bar  4  to cut threads in the walls of the hole and thus allow the cross bar  4  to be securely retained in the lateral lugs  11 . When so secured, the cross bar  4  bridges the pair of lateral lugs  11 . 
         [0036]    The position of the through countersunk hole  22  and the opposing hole  24  in their respective lateral lugs  11  is sufficiently spaced from the operative portions  5 ,  18  of their respective part  2 ,  3  so as to create a slot  29  between such operative portions  5 ,  18  and the cross bar  4  when received therein. Furthermore, the slot  29  must be of sufficient width to allow the webbing  21  to be threaded therethrough and around the cross bar  4  so as to create the capturing loop  20 . 
         [0037]    Each cross bar  4  comprises a screw head  23 , a self tapping threaded end  25  and a shaft part  33 . The head part  23  is tapered in a countersunk fashion as would be well known to the person skilled in the art. Furthermore the head part  23  is dimensioned so as to fit through countersunk hole  22 . This allows the head part  23  to sit flush and in level with top surface  27  of lateral lug  11   b  when the cross bar  4  is properly inserted in through countersunk hole  22 . 
         [0038]    The screw head  23  also has a cross-shaped depressed slot  28  provided therein to facilitate removal of the cross bar  4  by way of a Philips screw driver. 
         [0039]    The self tapping threaded end  25  has a series of threads which are sufficiently sharp enough to cut threads into side walls (not shown) of opposing hole  24 . In this preferred embodiment, the threaded end  25  has a length roughly equal to the depth of the opposing hole  24 . 
         [0040]    The shaft part has a smooth external machine finish to minimise abrasion on the webbing  21 . 
         [0041]    Each cross bar  4  is made from stainless steel. 
         [0042]    This embodiment will now be described and further explained in the context of its intended use. 
         [0043]    A first webbing  21   a  is obtained and a capturing loop  20  formed therein. 
         [0044]    Simultaneously, or thereafter, a second webbing  21   b  is obtained and a capturing loop  20  also formed therein. 
         [0045]    In both cases, the capturing loop  20  is sized and dimensioned such that there is very little free space provided therein once a cross bar  4  extends therethrough. 
         [0046]    With the capturing loops  20  formed, each piece of webbing  21  is positioned such that the axis (A-A) of the capturing loop  20  aligns with the countersunk hole  22  and opposing hole  24  of its respective part  2 ,  3 . 
         [0047]    With respect to each part  2 ,  3 , a cross bar  4  is then inserted first through the countersunk hole  22  with the self tapping threaded end  25  leading. Following clearance of the countersunk hole  22 , the self tapping threaded end  25  enters the capturing loop  20  in line with axis (A-A). The cross bar  4  then continues to be inserted through the capturing loop  20  until such time as the self tapping threaded end  25  meets opposing hole  24 . At this position, a Philips head screwdriver must engage the cross shaped depressed slot  28  to impart rotational force to the cross bar  4 . 
         [0048]    This rotational force allows the sharpened threads of the self tapping threaded end  25  to cut into the side walls of the opposing hole  24 . This continues until all of the threads of the self tapping threaded end  25  are received within the opposing hole  24 , leaving the capturing loop  20  encapsulating the smooth surface of the shaft part  33 . 
         [0049]    With the webbing  21  now appropriately secured to their respective parts  2 ,  3 , a secured, releasable buckle  1  is formed as follows. 
         [0050]    As the bulbous ends  15  of each lateral prong  12  slopes towards its distal end  34 , when the distal end  34  of the male prong part  2  is inserted into an engaging opening  7  at the distal end  26  of the cavity  6 , the bulbous ends  15  engage with the lateral walls  19  of the cavity  6  and cause the lateral prongs  12  to compress and flex towards the central spine  13 . This enables the male prong part  2  to be progressively narrowed while being inserted into the cavity  6 . 
         [0051]    When the male prong part  2  has reached its maximum inserted position within the female socket part  3 , the lateral prongs  12  are no longer constrained by the cavity  6 . As a result, the accumulated flexing force of the lateral prongs  12  is released, causing them to spring outwards. This movement also sees the bulbous ends  15  snap into lateral apertures  10  located near the proximal end of the female socket part  3 . 
         [0052]    At this point, the shoulder  16  of the male prong  12  and the wall surface  17  of the lateral aperture  10  overlap dimensionally and thereby create a secure mechanical connection between the male prong part  2  and the female socket part  3 . 
         [0053]    The buckle  1  may thereafter be released by applying inward pressure to the lateral prongs  12  such that they move towards the central spine  13 . As this inward pressure increases, the lateral prongs  12  will reach a point where the bulbous ends  15  can disengage from the lateral apertures  10 . When so disengaged, the male prong part  2  can then be removed from the female socket part  3 , by applying a separating force to one or both respective webbings  21 . 
         [0054]    Once disengaged, the cross bar  4  may then be removed by reversing the process described above. This can then allow the buckle  1  to be replaced as required. 
         [0055]    It should be readily apparent to the person skilled in the art that the above description illustrates a buckle  1  which can easily be replaced in the field in the event that the buckle is rendered useless due to damage to any of its constituent parts. Similarly, it should be noted by the person skilled in the art that as the cross bar  4  is not an integral component of either part  2 ,  3  the technical limitations of sewing machines as described above becomes irrelevant. Rather the countersunk hole  22  and opposing hole  24  can be placed anywhere in the lateral lugs  11  provided that this creates a slot  29  of sufficient size to allow a relevant portion of the capturing loop  20  to pass therethrough. 
         [0056]    It should also be appreciated by the person skilled in the art that the above invention is not limited to the embodiment described. In particular, the following modifications and improvements may be made without departing from the scope of the present invention:
       The male prong part  2  and female prong part  3  may also be made of Poly Amide copolymer plastics or resins but any suitable material known in the art for moulding or machining side release buckles can be used.   Similarly, the cross bars  4  may be made from any material known in the art for moulding or machining bolts, pins or screws.   The buckle  1  may take a form other than the side release buckle described above. For instance, the buckle  1  may take any other two-part form used to latch two webbing parts or straps together. In this respect, the securing mechanism for fixing the webbing parts or straps together can take any form that incorporates a bar and capturing loop configuration as would be known to the person skilled in the art.   It should also be noted that in two part buckle configurations, only one part need employ a cross bar  4 . The other part may take the form of a double slot arrangement in which the webbing  21  is simply threaded through these slots. This is a common arrangement in situations where the buckle  1  is not designed to be captured at a fixed location along the webbing  21 .   Similarly, the invention may also be employed in single part buckles employing a ladder lock configuration as described above.   An end of the webbing  21  not attached to one of the parts  2 ,  3  may be affixed to an article. Alternatively, the respective ends of the webbing  21  may each terminate in a capturing loop  20  that affixes to a respective part  2 ,  3 .   The screw head  23  may be made in any desired shape.   The screw head  23  may have a differing shaped depressed slot  28  provided therein to facilitate removal of the cross bar by way of other standard or customised screw driving tools.   The male prong part  2  and female socket part  3  may be adapted such that their respective lateral lugs  11  are able to retain multiple cross bars  4  in the manner described above.   The cross bar  4  may omit the self tapping threaded end  25  with other mechanisms for securing the cross bar  4  within opposing hole  24 . For instance, the cross bar  4  and opposing hole  24  may be appropriately magnetised to facilitate secure magnetic retention of the cross bar  4  within the opposing hole  24 .   Other means of securing the cross bar  4  in the opposing hole  24  include incorporating a spring loaded latch within the buckle, the latch being operable to engage with a notch provided in the cross bar  4  when the cross bar is received within the opposing hole  24 . Alternatively, the self-tapping threaded end  25  of the cross bar  4  may be replaced with a bolt stud incorporating threaded components, such a cross bar  4  may then be adapted to be screwed into a nut on one or both sides of the opposing hole  24 .   While the capturing loop  20  has been described as being made from webbing, the capturing loop  20  may be formed from an attachment, or attachments, to the webbing. Such attachments are many and varied, but all must have the necessary dimensions to pass through slot  29 .   Alternatively, the attachment may be directly affixed to an item without any intermediate webbing, the attachment simply acting as a capturing loop  20  for the item.       
 
         [0070]    It should be further appreciated by the person skilled in the art that the above variations and modifications, not being mutually exclusive, can be combined to form yet further embodiments that fall within the scope of the present invention.