Method of manufacturing a flat flexible conductor cable

Abstract

 A method of manufacture of a flat conductor cable (10) in which, prior to enclosing one or more flat conductor(s) (12) within an envelope of insulation material, at least one window (16,18,20) is formed in the insulation material (14), so that when the or each conductor is enclosed within the envelope it is exposed at the position(s) at which a connector is to be mounted on the cable. This method allows accurate positioning of the windows in the insulation material and also saves a great deal of time in the installation of a cabling assembly.

Description

[0001] The present invention relates to flat flexible conductor cables of the kind which may, for example, be used in under-floor or under-carpet cabling applications.

[0002] In general, such cables consist of one or more flat flexible conductors within an envelope formed of two layers of insulating material which are, in general, secured to one another by welding or other similar techniques.

[0003] Hitherto, it has been usual practice to supply such flat conductor cables as continuous lengths on reels or the like and to cut appropriate lengths for use in particular cabling assemblies. One problem which arises is that the insulation film must be removed prior to securing a connector to the cable; where a connector is to be placed partway along a cable run, the insulation is usually removed by grinding the cable during assembly of the installation. This had the disadvantage that it is time consuming and, further, that accurate positioning of the openings or windows in the insulation film is difficult leading to problems with accurate alignment of the windows formed in the insulation film with the contacts of the connector assembly to be fitted to the cable.

[0004] We have appreciated that these problems could be largely overcome by manufacturing cable runs for specific cable assemblies with the windows in the insulation film being formed during manufacture at predetermined positions. This allows accurate positioning of the windows in the insulation and, further, gives rise to considerable cost and time saving in producing a finished flat flexible conductor cable assembly.

[0005] The invention provides a method of manufacture of a cable of a kind comprising one or more flat conductor(s) enclosed in an envelope of insulating material. The method is characterised by forming at least one opening in the insulating material at one or more predetermined position(s) prior to enclosing the or each conductor within the envelope of insulating material, so that when the or each conductor is enclosed within the envelope (14) it is exposed at one or more predetermined position(s).

[0006] The invention further provides a method of making a cabling assembly characterised by attaching one or more connector(s) to each of a plurality of cables at one or more openings(s) in the insulation envelope of each cable, formed during manufacture of the cable, at which the or each conductor is exposed, and thereby connecting the cables.

[0007] The invention will now be described in greater detail, by way of example, with reference to the drawings, in which:

Figure 1 is a fragmentary perspective view showing a length of flat flexible conductor cable manufactured in accordance with the invention;

Figure 2 is a section through the cable of Figure 1 taken on line X-X; and

Figure 3 shows additional features of the cable of Figure 1 which may be formed during manufacture.

[0008] As mentioned above, a flat flexible conductor cable 10 comprises one or more flat flexible conductors 12 arranged parallel to one another and enclosed within an insulating envelope 14 shown most clearly in Figure 2. The insulating envelope 14 is most conveniently formed by placing the conductors 12 between two sheets of insulating material and securing the sheets together along their edges and between the conductors 12 by means of welding or other suitable techniques.

[0009] Where a connector is to be mounted on the cable 10, it is necessary to expose the conductors 12 by removing the insulating envelope 14. In the cable of the invention, this is achieved during manufacture, by cutting away the insulating film that forms the envelope 14 either completely, as shown at 16 or at predetermined areas to expose specific conductors 12, as shown at 18 and 20 in Figure 1.

[0010] Formation of these "windows" in the insulating envelope can be achieved by punching or any other cutting operation which is suitable given the materials used. Because the windows in the insulating envelope are formed during manufacture, it is possible to position them accurately so as to avoid difficulties in forming proper soldered contacts with the connector assembly and it is anticipated that length of cables for a given assembly will be manufactured on a "bespoke" basis with windows being formed in the insulation envelope 14 only where they are necessary for a specific installation.

[0011] Because the windows are pre-cut during manufacturing, additional features can be provided, as shown in page 2. For example, openings 22 for engagement with a connector assembly can be provided in the welded part of the envelope 14 as shown at 22 in Figure 3. These engage with the connector assembly so as to provide strain relief.

[0012] In one embodiment of the invention at least one pair of openings 16,22 is formed in the insulating material. The first opening of the pair exposes the conductor 12 at a predetermined position, for example a position at which it is necessary to mount a connector on the cable. The conductor engages in the second opening of the pair mechanically to provide stain relief.

[0013] In one embodiment of the invention the edges of the insulation envelope 14 can be notched as shown at 24 in Figure 3 to ensure that the connector assembly is properly located on the cable 10, for example, to ensure that the connector is mounted with proper polarity relative to the cable conductors 12. In this embodiment of the invention the method of manufacture of a cable includes additionally forming one or more opening(s) in the insulating material which, in the finished cable 10, form one or more location notches 24 at the edge of the insulating envelope 14 at one or more predetermined position(s) to facilitate location of other components in relation to the cable.

[0014] Because all of these features are pre-formed during manufacture of the cable, accurate positioning of the opening(s) is possible.

Claims

1. A method of manufacture of a cable (10) of a kind comprising one or more flat conductor(s) (12) enclosed in an envelope (14) of insulating material the method being characterised by forming at least one opening (16,18,20) in the insulating material at one or more predetermined position(s) prior to enclosing the or each conductor within the envelope of insulating material so that when the or each conductor is enclosed within the envelope (14) it is exposed at one or more predetermined position(s).

2. A method according to claim 1 in which there are formed at least one pair of openings (16,18,20,22) in the insulating material such that, in use, a first opening (16,18,20) of the pair permits a connector to contact the conductor (12) exposed at the said opening, and the connector engages in the second opening (22) of the pair mechanically so as to provide strain relief.

3. A method according to claim 1 or 2 further characterised by additionally forming one or more openings in the insulating material which, in the finished cable (10), form one or more location notch(es) (24) at the edge of the insulating envelope (14) at one or more predetermined position(s) to facilitate location of other components in relation to the cable.

4. A method of making a cabling assembly characterised by attaching one or more connector(s) to each of a plurality of cables (10) manufactured according to the method of any of claims 1 to 3 at one or more of the predetermined position(s) at which the conductor (10) is exposed, and connecting the plurality of cables by means of said connectors.

Drawing