Abstract:
Cable connector including a connector housing and a cable clamp for clamping a cable to the housing. The cable clamp having an intermediate portion between a first and a second mounting portion. At least one of the two mounting portions of the cable clamp is provided with locking means selectively cooperative with at least two matching locking means, such as slots, of the connector housing to hold the cable clamp in respective different positions corresponding to different cable diameters.

Description:
FIELD OF THE DISCLOSURE 
       [0001]    The present invention relates to the field of connectors, in particular electrical cable connectors. 
       BACKGROUND OF THE DISCLOSURE 
       [0002]    In the field of connectors, in particular cable connectors, it is known to use a cable clamp, clamping the cable to the connector housing, for strain relief. Generally, the cable clamp is screwed to the housing. This requires screws, thus additional separate parts, and the screwing complicates assembly of the connector. 
         [0003]    The connector housing and/or the cable clamp generally are formed providing an opening optimized for receiving a cable of a particular outer diameter and compressibility. Such connectors are not well suited for accommodating a cable of a different diameter and/or compressibility. 
         [0004]    If the opening for the cable is small, portions of the cable may be pinched or crushed, which affects its transmissive and/or structural properties. This is in particular the case for cables for signal transmission, especially high speed signal transmission, and for multi-wire cables. Conversely, a large cable opening may allow slipping of the cable with respect to the housing, possibly affecting or compromising connections of and/or to the cable inside the housing. Thus, connectors having a cable clamp may have limited usefulness for many purposes. As a result, stocking and/or selling various sizes and types of connector housings and/or cable clamps for suitably clamping different cables is required. This substantially increases costs. 
         [0005]    Therefore, a need exists for an improved cable connector reducing or alleviating the above-referenced problems. 
       SUMMARY OF THE DISCLOSURE 
       [0006]    An object of the present invention is to provide a cable clamp that can be used for different cable diameters. This object is achieved with a cable connector comprising a connector housing with an opening for receiving a cable, and a cable clamp mounted to the connector housing wherein the clamp comprises an intermediate section between two or more mounting portions, at least one of the mounting portions comprising locking means for interlocking with one of at least two cooperative locking means of the housing. When the cable clamp is put in place in the housing, one of the two or more present locking means in the housing can be selected, depending on the type of cable to be clamped. This way, the position of the cable clamp can selectively be adjusted between at least two alternative clamping positions so it can be used for more than one cable diameter. 
         [0007]    Optionally, the housing comprises at least two slots, each being dimensioned to interlock a locking means formed by a matching extension of the cable clamp. Alternatively, the clamp can be provided with one or more slots dimensioned to cooperate with one or more matching interlocking means, such as hooks or projections, of the housing. 
         [0008]    With only one slot of the two or more slots being used, the slots which have not been brought into engagement with the matching cable clamp extension, can for example be covered by a foil of electromagnetic shielding material. This prevents that the unused slot or slots forms a leak in the electromagnetic shielding. Alternatively, the slots can be replaced by blind holes. 
         [0009]    The cable clamp extension forming the locking means comprise for example a hook. 
         [0010]    To improve the grip of the cable clamp on the cable jacket, the intermediate portion of the cable clamp may be provided with one or more piercing teeth, e.g., piercing into the cable jacket. Optionally, the teeth may penetrate through the braid that has been folded back on the isolating jacket or sheath at the end of the cable, so as to bite into the isolating sheath so as to improve EMI shielding. 
         [0011]    The intermediate portion can be provided with a flange bridging the gap between the intermediate portion and the adjacent edge of the cable receiving opening. The flange can be made of an electromagnetic shielding material. 
         [0012]    In an alternative embodiment the intermediate cable clamp portion is provided with resilient teeth alternately folded in opposite directions. In use, the teeth resiliently clamp against the cable jacket. Such an arrangement of resilient teeth can effectively reduce freedom of forward movement of the clamped cable as well as backward movement. 
         [0013]    In a further alternative embodiment, the intermediate section comprises at least two curved sections of different curving diameter. This way, the clamp can be used for stiffer cables having a diameter corresponding to one of the curved sections, and it can also be used for cables of larger diameter with higher compressibility. 
         [0014]    An object of the invention is also achieved with a cable connector comprising a connector housing with an opening for receiving a cable, and a cable clamp mounted to the connector housing wherein the cable clamp comprises an intermediate section between two or more mounting portions, wherein the intermediate cable clamp portion is provided with resilient teeth alternately folded in opposite directions to resiliently clamp against the cable jacket. Optionally, the intermediate portion of the cable clamp is provided with a series of outwardly bent shielding teeth, to cover the gap between the intermediate portion and the interior edge or wall of the cable opening and to complete the electromagnetic shielding. These teeth may have rounded end parts, e.g., be mushroom shaped, to maximize coverage of the gap between the cable clamp and the cable opening. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1 : shows in perspective view a connector according to the present invention; 
           [0016]      FIG. 2A : shows in perspective view the interior of the connector of  FIG. 1 ; 
           [0017]      FIG. 2B : shows in perspective view a multi-connector variant of the connector of  FIG. 2A ; 
           [0018]      FIG. 3A : shows a side view of the cable clamp of  FIG. 1 ; 
           [0019]      FIG. 3B : shows a plan view of the cable clamp of  FIG. 1 ; 
           [0020]      FIG. 3C : shows a perspective view of the cable clamp of  FIG. 1 ; 
           [0021]      FIG. 4 : shows a perspective view of a second embodiment of a connector according to the invention; 
           [0022]      FIG. 5A : shows a perspective view of a cable clamp of the connector of  FIG. 4 ; 
           [0023]      FIG. 5B : shows a side view of the cable clamp of  FIG. 5A ; 
           [0024]      FIG. 6A : shows a perspective view of a third embodiment of a connector according to the invention; 
           [0025]      FIG. 6B : shows another perspective view of the connector of  FIG. 6A ; 
           [0026]      FIG. 7A : shows a perspective view of the cable clamp of the connector of  FIG. 6A ; 
           [0027]      FIG. 7B : shows a side view of the cable clamp of  FIG. 7A . 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0028]      FIG. 1  shows in perspective view a cable connector  1  comprising a connector housing  2  and a cable clamp  3  for clamping a cable (not shown) to the housing  2 . 
         [0029]    The housing  2  is made of two matching casing sections  4 ,  5  both comprising a semi-circular collar section  6 ,  7  together forming a cylindrical collar  8  when both casing sections  4 ,  5  are joined together to form the housing  2 .  FIG. 2  shows the interior of the connector  1  with the shell section  5  broken away. The collar  8  surrounds an opening  9  in the housing  2  for receiving a cable. In line with the collar  8  located within the housing  2  is a cable clamp  3 , which is shown in more detail in  FIGS. 3A-C . 
         [0030]    The cable clamp  3  comprises a first mounting portion  11 , a second mounting portion  12  aligned with respect to the first mounting portion, and a curved intermediate portion  13 . The first mounting portion  11  has a rounded end and comprises an opening  14  allowing passage of a fixation screw, as shown in  FIG. 2 . According to a preferred embodiment, the second mounting portion is provided with a bend portion or makes an angle with respect to the first mounting portion in order to make the mounting step easier. 
         [0031]    The second mounting portion  12  forms a locking means provided with a slanting top edge  15 . 
         [0032]    The curved intermediate portion  13  has a concave side provided with five evenly distributed triangular teeth  16 . On its convex side, the clamp  3  is provided with a collar or flange  17 . To facilitate bending the flange  17 , openings or slots  18  are provided on the folding line  19  of the flange  17 . 
         [0033]    The clamp  3  and the housing  2  are made of an electromagnetic shielding material. 
         [0034]    The top side of the housing  2  is provided with locking means formed by slots  20 ,  21 , both dimensioned to receive locking means  12  of the cable clamp  3 . When the locking portion  12  is put into the first slot  20 , the clamp leaves open a larger opening for passage of a cable than if portion  12  is put into the second slot  21 . As a result, cables of different diameter can be clamped using the same cable clamp  3 . If a smaller diameter cable is used, the cable clamp portion  12  is brought into engagement with slot  21 . In that position, flange  17  covers the gap between the curved clamp portion  13  and the housing wall surrounding cable opening  9 . Flange  17  can be made of an electro conductive material. The interior wall of the housing facing the flange  17  can be provided with projections or teeth contacting flange  17 . This way, flange  17  completes the electromagnetic shielding of the connectors interior. 
         [0035]    When a cable is clamped in the opening  9  by clamp  3 , the triangular teeth  16  pierce into the cable jacket to give improved fixation of the cable. Optionally, the teeth penetrate through the braid that has been folded back on the isolating jacket or sheath at the end of the cable, so as to bite into the isolating sheath so as to improve EMI shielding. Alternatively, the teeth penetrate through the isolating sheath to such extent that it contacts the underlying conductive shielding braid. 
         [0036]    Slots  20 ,  21  may be dimensioned to limit passage of electromagnetic wavelengths above a particular cut-off wavelength of electromagnetic noise, corresponding to a lower frequency limit for EMI noise. Optionally, slots  20 ,  21  can be sealed with a foil of an electromagnetic shielding material. When the clamp portion  12  is brought into engagement with one of the slots, the corresponding seal is broken while the other slot remains sealed. 
         [0037]    The slanting edge  15  of cable clamp portion  12  juts out off the slot  20 ,  21 , allowing visual inspection, particularly if the portion  12  and the housing  2  have different colours, shades or brightness. 
         [0038]    The opening  9  in housing  2  is provided with ribs or protrusions or teeth  22  to further reduce movement of the cable. 
         [0039]    The cable to be used comprises electro conductive wires to be connected to contact points in a terminal block  23  closing off the housing  2 . 
         [0040]    In  FIG. 2B , a double connector is shown comprising a cable clamp  3 A similar to the cable clamp in  FIG. 2A  but with a larger flange  17 A. A resilient fin  24  presses the flange  17 A against the interior housing surface peripheral to the cable opening. Corner parts  25  with an L-shaped cross section surround the two side edges of the flange  17 A, protecting the fin  24  from breaking when a certain force is exercised onto the cable and the cable clamp in the direction of fin  24 . 
         [0041]    A set of different exchangeable cable clamps can be used having different sizes of flanges. Clamps for cables of smaller diameter have to bridge a larger gap between the clamp and the cable opening edge and can for that purpose be provided with larger flanges. A set can for instance include the clamp  3  of  FIG. 2A  and the clamp  3 A of  FIG. 2B  and optionally further type variations, wherein each clamp type can be used for two or more corresponding cable diameters. 
         [0042]    Another embodiment of a cable clamp  103  according to the present invention is shown in  FIGS. 4 and 5A  and  5 B. 
         [0043]      FIG. 4  shows a housing  102  with an opening  109  for receiving a cable. In line with the opening  109  is a cable clamp  103 , shown in detail in  FIGS. 5A and 5B . The cable clamp  103  comprises a first portion  11  with an opening  114  allowing passage of a fixation screw, a second portion  112  provided with a hook  115 , and a curved intermediate portion  113 . End portions  111  and  112  are bent over right angles with the intermediate portion  113 . On its concave side, the curved intermediate portion  113  is provided with teeth or leaf springs  116  alternately bent in opposite directions. The convex side of the curved portion  113  is provided with a series of mushroom shaped projections  117 , bent under an angle of about 60-70 degrees relative to the intermediate portion  113 . 
         [0044]    When mounted in a connector housing and after connecting a cable to the connector, hook  115  of portion  112  is brought into engagement with a corresponding slot in the housing  2  and a fixation screw fixes the clamp via opening  114  in end portion  111 . Teeth  116  resiliently clamp on the cable. Due to the alternating orientation of the teeth backward as well as forward movement of the cable is effectively reduced. The mushroom shaped projections  117  resiliently engage with the interior wall of opening  109 , effectively bridging the gap between the cable clamp  113  and the interior wall of opening  109  and completing the electromagnetic shielding. The resiliency of the mushroom shaped projections  117  increases the range of cable diameters that can be used with the cable clamp  103 . 
         [0045]    A third embodiment of a cable clamp  203  according to the invention is shown in  FIGS. 6A-7B .  FIG. 6A  shows a triple cable connector having three cable openings  209  and cable clamps  203 . As shown in detail in  FIG. 7A , the cable clamps  203  are provided with a first end portion  211  with an opening  204  for a fixation screw or similar fastening means, and a second end portion  212  with a hook  215 . As shown in  FIG. 6B , hook  215  is mounted in a corresponding slot  220  in housing  202  of the connector. The cable clamp  203  has a curved intermediate section  213  having a profile with two rounded bulges of different diameter. Such a clamp can be used for stiffer cables having a diameter corresponding to either one of the bulges  222 ,  223 , but also for more compressible cables with a larger diameter. 
         [0046]    The described embodiments are intended to be illustrative rather than restrictive. Various modifications, variations and re-combinations of features of the embodiments as described can be made without departing from the spirit or scope of the disclosure.