Abstract:
A connector is described particularly for use to secure two lengths of chain together. Preferred embodiments of the connector have two parts each receiving respective chain links. The parts can snap together to maintain a connection and have abutment portions which abut with each other to provide a firm connection. There is no need to add bolts or the like to the connector to form or maintain the connection. Thus a reliable connection is achieved.

Description:
FIELD OF THE INVENTION  
       [0001]     This invention relates to a connector for connecting two parts together, particularly but not exclusively for connecting links of chain together.  
       DESCRIPTION OF THE RELATED ART  
       [0002]     The use of chains is well known in all types of industry and in practice it is often required to connect two separate chains together by connecting the links on the end of each chain.  
         [0003]     U-shaped hooks (not shown) can be welded together to form a chain link around the links of the end of the two pieces of chain in order to make a larger piece of chain. However, this requires specialist equipment which is expensive and frequently unavailable when the two pieces of chain are required to be connected.  
         [0004]      FIG. 1  shows an alternative, conventional chain connector comprising two U-shaped hooks  10 ,  20  each adapted to receive a chain link (not shown) in each of the U-shaped hooks  10 ,  20 . A pin  12  engages apertures in the U-shaped hooks  10 ,  20  in order to connect them together.  
         [0005]     However, a problem with such a conventional design is that the pins  12  can fall out during use resulting in failure of the connector, disengagement of the pieces of chain and potentially serious consequences should the chain be in use and supporting a structure of any sort when the connector fails.  
       SUMMARY OF THE INVENTION  
       [0006]     According to the present invention, there is provided a connector comprising:  
         [0007]     a first part shaped to receive a first member;  
         [0008]     a second part shaped to receive a second member;  
         [0009]     wherein the first and second parts each have an abutment portion shaped to abut against the other abutment portion of the first and second parts in order to form a connection between the first and second parts.  
         [0010]     Typically the first member and second member are chain links. Preferably therefore the first and second parts are shaped to receive first and second chain links respectively.  
         [0011]     Typically the first chain link has a chain extending therefrom and the second chain link has a chain extending therefrom.  
         [0012]     Preferably, the abutment portions are adapted to abut against each other to resist movement of the first and second parts in the direction of pull of the chain.  
         [0013]     Preferably, at least one of the first and second parts comprises alignment portion adapted to align the other of the first and second parts therewith whilst forming a connection.  
         [0014]     The alignment portion may be a portion of material extending from the abutment portion which defines a slot through which the other of the first and second parts can engage.  
         [0015]     Preferably, the portion of the first part shaped to receive a first chain link comprises a retention mechanism in order to maintain the connection between the first and second parts.  
         [0016]     Preferably, the first part is resilient so that it is adapted to extend around the retention mechanism when forced to do so by a user.  
         [0017]     Preferably, the first part is adapted to form a snap fit with the second part and more preferably the second part forms a snap fit with the first part.  
         [0018]     The retention mechanism may be a nib extending outwards from the said portion of the first part.  
         [0019]     Preferably, the second part also comprises such a retention mechanism.  
         [0020]     Preferably, the portion of the first part which is shaped to receive a first member comprises a U-shaped hook. Typically, the portion of the second part which is shaped to receive the second member also comprises a U-shaped hook.  
         [0021]     Optionally, the first and/or second parts are horse-shoe shaped. Thus the retention mechanism may be a relatively wide portion of the first or second parts.  
         [0022]     Preferably, the portion of the first and/or second part which is shaped to receive the first and/or second member has a curved cross-section. More preferably, it has an elliptical cross-section although a circular cross-section may be provided for certain embodiments.  
         [0023]     Preferably, the cross-section of the second part which is shaped to receive the second member also has a curved cross-section. Preferably, but not necessarily, this part is also elliptical.  
         [0024]     Preferably, the diameter of the cross-section of the first and second parts is greater in the direction of pull of the chain when the chain is in a linear alignment with the connector than the diameter perpendicular to said pull of chain in said alignment.  
         [0025]     Typically the first and second parts are integrally formed with their respective abutment portions.  
         [0026]     Preferably, features of the first part are provided in the second part. More preferably, the first and second parts are substantially identical. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0027]     An embodiment of the present invention will now be described by way of example only, with reference to the accompanying drawings, in which:  
         [0028]      FIG. 1  is a top view of a conventional chain connector;  
         [0029]      FIG. 2  is a top view of a connector in accordance with the present invention;  
         [0030]      FIG. 3  connector is a perspective view of a first half of the  FIG. 2  connector; and  
         [0031]      FIG. 4  is a perspective view of the  FIG. 2  connector. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0032]     A connector  100  in accordance with the present invention is shown in  FIGS. 2-4  and comprises a first connector half  110  and a connector second half  120 . The halves  110 ,  120  of the connector  100  are identical and adapted to fit together, as shown in  FIGS. 2 and 4 , and described herein below. Each half  110 ,  120  will be described by reference to the first half  110 .  
         [0033]     The first half  110  of the connector  100  comprises a U-shaped hook  111 , lugs  113  and alignment slots  114 .  
         [0034]     The U-shaped hook  111  comprises two legs  115   a  &amp;  115   b . An arc-shaped portion  116  connects the two legs  115   a  &amp;  115   b  together in order to form the U-shape of the U-shaped hook  111 .  
         [0035]     The legs  115   a  &amp;  115   b  are generally straight and parallel to each other although may be slightly curved as described below, in order to aid retention of the connection between the halves  110 ,  120  in use.  
         [0036]     At the other end of each of the legs  115   a  &amp;  115   b , lugs  113  project outwardly away from the other leg  115   b ,  115   a . The lugs  113  curl around and then extend out of the plane defined by the U-shaped hook  111 . Lastly the lugs  113  curl around again and extend back towards each other.  
         [0037]     This shape of the lugs  113  defines slots  114  for engagement with legs  125   a  &amp;  125   b  of the other U-shaped hook  121 .  
         [0038]     Nibs  130  are provided on the legs  115   a  &amp;  115   b  and extend outwardly therefrom. Movement of the lugs  123  or legs  125   a  &amp;  125   b  of the other connector half  120  thereover is thereby resisted. In this way, the connector halves  110 ,  120  do not come apart in use but can be pushed or ‘snapped’ together over the nibs  130  to connect.  
         [0039]     Similarly the U-shaped hook  111  can be very subtly, almost imperceptibly, horse-shoe shaped. That is, the distance ‘A’ between outer sides of mid-sections of the legs  115   a  &amp;  115   b  can be slightly longer than the distance ‘B’ between the outer sides of the end of the legs  115   a  &amp;  115   b  (next to the lugs  113 ). Therefore during connection and disconnection the lugs  123  defining the slots  124  of the other connector half  120  are snapped over this relatively large mid-section A to rest around the said ends of the legs  115   a  &amp;  115   b  between the lugs  113  and the relatively large mid-section A. The relatively large mid-section A resists movement of the connector half  110  through the slots  124  which could result in inadvertent disconnection of the halves  110 ,  120 .  
         [0040]     The lugs  113  at the end of the legs  115   a ,  115   b  are therefore resilient enough to be snapped over the mid-section A or nibs  130 .  
         [0041]     The cross-section of the U-shaped hook  111  is preferably oval or elliptical with the greater cross-sectional diameter being in the direction of pull that the connector  100  will experience when the attached chain is in linear alignment with the connector  100 , that is generally parallel with the legs  115   a  &amp;  115   b.    
         [0042]     Certain embodiments of the present invention benefit from the feature that they have an oval-shaped cross-section so that there is no point to point contact between the chain link they are connecting to and the U-shaped hook. This makes the connector more robust and less liable to wear and tear in addition to other advantages.  
         [0043]     As described above, in preferred embodiments the connector halves  110 ,  120  are identical to each other and so the features described above with respect to the first connector half  110  are also present in the second connector half  120  and vice versa.  
         [0044]     Thus, to connect a first and second chain together a first link (not shown) from the end of the first chain (not shown) is placed within the U-shaped hook  111  and a second link (not shown) from the second chain (not shown) is placed in the U-shaped hook  121 . The connector halves  110 ,  120  are oriented so that their main planes are parallel to each other, their lugs  113 ,  123  extend outwards from said planes towards each other and their arc-shaped portions  116 ,  126  are next to the lugs  123 ,  113  of the opposite connector half  120 ,  110 .  
         [0045]     The arc-shaped portions  116 ,  126  of the connector halves  110 ,  120  are directed past the slots  124 ,  114  of the other connector half  120 ,  110  and the legs  115   a  &amp;  115   b ,  125   a  &amp;  125   b  of each connector half  110 ,  120  engages with the slots  124 ,  114  of the other connector half  120 ,  110 . The connector halves  110 ,  120  are snapped over the nibs  130  (or the relatively wide mid-section ‘A’ of the legs  125   a  &amp;  125   b ,  115   a  &amp;  115   b ) of the other connector half  120 ,  110  and continue moving until their lugs  113 ,  123  on each side of their respective legs  115   a  &amp;  115   b ,  125   a  &amp;  125   b  abut with each other and prevent further movement. Thus, a connection between the first and second chain is achieved.  
         [0046]     The connection is maintained during use by the nibs  130  or relatively wide mid-section ‘A’, providing a barrier to the parts disconnecting.  
         [0047]     Thus, embodiments of the present invention benefit from the fact that there are no pins or bolts to be inserted between the two parts of the connector thus making them far more reliable than certain previous connectors.  
         [0048]     An advantage of certain other embodiments of the invention is the ease in which the connection may be made and removed.  
         [0049]     The connector  100  is preferably manufactured when using the technique of drop forging. It is certified to British Standards BS5950 and preferably to chain grade 80. Thus certain embodiments of the invention benefit from the fact that they can be used for heavy loads in the lifting industry.  
         [0050]     The cross-section of the U-shaped hooks  111 ,  121  is preferably slightly larger than that of the chain which they are joining. For example, the thickness of the U-shaped hook  111  around the arc-shaped portions  116  and legs  115   a  &amp;  115   b  may be 10 mm whereas the chain pieces they are joining may be 7 mm.  
         [0051]     The material used is 80 ton tensile steel (EN24) which is a high grade chromium/molybdenum steel which is hardened and tempered.  
         [0052]     Improvements and modifications may be made without departing from the scope of the invention.