Abstract:
A cable system is made up of several cables each having several wires extending side-by-side. The wires in each cable are retained together in a flat configuration by removable clips and these are retained together in frames. The clips at the end of the cables support the wires so that they can all be stripped and attached to connector contacts together.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates to cables, cable systems, parts and methods.  
           [0002]    Conventional cable systems include a bundle of wires connected at opposite ends to respective connectors. The bundle of wires is usually of a generally circular section, which can cause difficulties. Because the wires do not retain a predetermined position within the bundle along its length they have to be marked in some way for identification purposes. It also means that the wires have to be individually stripped of insulation and terminated, which is time consuming. Because each wire may extend close to any other wire, signals on one wire can cause interference on any other wire. For this reason, there are advantages to flat cable systems where each wire extends side-by-side at a predetermined position across a row of wires. There are, however, problems with flat cable systems. The manufacture of flat cables where the insulation is formed integrally for all the wires requires specialised manufacturing equipment leading to extra costs, especially where varying numbers or types of wires are provided in a cable. For the same reason, it can also be difficult to secure separate wires in a flat configuration such as by bonding to one another or to a parallel support sheet. Flat cables can also be difficult to bend in a curve lying in the plane of the cable.  
         BRIEF SUMMARY OF THE INVENTION  
         [0003]    It is an object of the present invention to provide an alternative cable, cable system, part and method.  
           [0004]    According to one aspect of the present invention there is provided a cable having a plurality of separate wires and a plurality of retaining members spaced from one another along the cable, the retaining members locating the wires side-by-side with one another in a planar array.  
           [0005]    The retaining members preferably retain the wires in a removable manner. The retaining members preferably have a plurality of separate locations adapted to receive respective individual ones of the wires. The locations may be passages through the retaining member. The retaining members are preferably clips fastened about the wires. Each clip may have two arms hinged with one another at one end and provided with locking catches at the other end.  
           [0006]    According to another aspect of the present invention there is provided a retaining member for use in a cable according to the above one aspect of the invention.  
           [0007]    According to a further aspect of the present invention there is provided a cable system including a cable according to the above one aspect of the present invention and a connector having a plurality of contact members connected with respective ones of the wires.  
           [0008]    According to a fourth aspect of the present invention there is provided a method of forming a cable including the steps of providing a plurality of wires, retaining the wires side-by-side with one another in a flat configuration using a plurality of retaining members, locating wire forming means with the cable against a retaining member and effecting a wire forming operation with the wire forming means on each wire simultaneously.  
           [0009]    The wire forming operation may be stripping of insulation.  
           [0010]    According to a fifth aspect of the present invention there is provided a method of forming a cable system including the steps of providing a plurality of groups of wires, retaining the wires side-by-side with one another in a plurality of groups using a plurality of retaining members, each group having a flat configuration, and retaining the groups with one another in an array with retaining means.  
           [0011]    According to a sixth aspect of the present invention there is provided a cable formed by a method according to the above fifth aspect of the invention.  
           [0012]    A cable system including a cable and retaining members, and a method of forming the cable, according to the present invention, will now be described, by way of example, with reference to the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is a perspective view of the cable system;  
         [0014]    [0014]FIG. 2 is a side elevation view of the system;  
         [0015]    [0015]FIG. 3 is a perspective view of a cable of the system;  
         [0016]    [0016]FIG. 4 is a transverse cross-sectional view across a single retaining clip of the system;  
         [0017]    [0017]FIG. 5 is a transverse cross-sectional view across a group of four retaining clips;  
         [0018]    [0018]FIG. 6 is transverse cross-sectional view across an alternative retaining clip; and  
         [0019]    FIGS.  7  to  10  illustrate steps in forming the cable system.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0020]    With reference first to FIGS.  1  to  4 , the cable system includes four cables  1  to  4  each having a bundle of ten wires  10  arranged in a flat configuration, with the four cables being arranged in a two-by-two array. Each cable  1  to  4  has three retaining members or clips, one clip  5  (FIG. 3) being located midway along the length of the cable and the other two  6  and  7  being located close to opposite ends. The system includes two connectors  8  and  9  to which individual ones of the forty wires  10  in the cables  1  to  4  are connected at opposite ends.  
         [0021]    The wires  10  in the cables  1  to  4  are separate from one another and may be identical with or differ from one another, each typically comprising a conductor  11  extending within an insulating sleeve  12 . One or more of the wires  10  may be screened by an outer braided sleeve, in the usual way. The retaining clips  5  to  7  are identical with one another and may be of various different constructions enabling the wires  10  to be retained side-by-side with one another in a flat, planar configuration. In the example shown in FIG. 4, the clip  5  is an integral moulding of a plastics material comprising two arms  51  and  52  hinged with one another at one end by a web  53  and having at their opposite ends cooperating catches  54  and  55 . Each arm  51  and  52  has ten recesses  56  of semi-circular section spaced along its length and adapted to receive an individual one of the wires  10  when the two arms are closed about the wires. The size of the recesses  56  is such that the wires  10  are firmly gripped when the clip is closed. The three clips  5  to  7  on each cable  1  to  4  are themselves retained with one another by a respective outer frame  13  to  15  in a two-by-two array, as shown in FIG. 5.  
         [0022]    Because the wires  10  in the cables  1  to  4  are separate from one another they do not need any special manufacturing. The clips  5  to  7  can be secured on the cables  1  to  4  at any convenient stage of manufacture and can easily be unfastened to allow for removal or replacement of wires. The clips  5  to  7  also allow the cables  1  to  4  to be bent readily in a bend lying in the plane of the wire bundles by releasing the clips to allow the wires to be pulled through as necessary and then fastening the clips again.  
         [0023]    The retaining means could take various different forms, such as shown in FIG. 6, where the retaining means  60  comprises a block  61  of a stiff, resilient plastics material having ten passages  62  of circular section extending therethrough arranged side-by-side with one another and each opening on one side of the block via a throat  63  of reduced width. Wires  10  are assembled in the retainer  60  by pushing each through one of the throats  63  into a respective passage  62 .  
         [0024]    The retaining means also have the advantage of facilitating forming operations on the ends of the wires  10 , such as stripping off the insulation sleeve  12  and soldering to a contact  80  of the connectors  8  and  9 . As shown in FIG. 7, the clip  6  at one end of a cable  1  is fastened about the wires  10  to allow a small length of the wires to protrude. FIG. 8 shows a wire-forming machine, in this case a tool or machine  90  for stripping off the insulation sleeve  12 , brought up to the cable  1  to contact and locate against the clip  6 . The stripping machine  90  may be a form of a conventional stripper used with single wires modified to strip simultaneously the insulation from the ten wires  10  protruding from the clip  6 . The clip  6  ensures that the ends of the wires  10  are correctly located relative to the stripping machine  90  to enable this operation to be performed. The machine  90  is then removed, as shown in FIG. 9. The next step, as shown in FIG. 10 is to bring up the connector  8  so that the exposed ends of the wires  10  project into contacts  80  in the connector. Again, the connector  8  is located against the clip  6  to ensure correct positioning relative to the wires. The wires  10  are then soldered into the contacts  80  in the usual way. This end forming and terminating operation may be performed separately on each of the four cables  1  to  4 , that is, ten wires at a time, or it may be performed simultaneously on the forty wires in the group of four cables after retaining the clips  6  in the outer frame  14  and by locating the forming machine with the frame.  
         [0025]    It will be appreciated that the invention could be modified in various ways.