GB2159546A - Woven ribbon cable - Google Patents

Abstract

A woven ribbon cable especially for use in connection with computer or micro processor related devices has warpways running conductors woven with a textile yarn weft. Spacer yarns are provided between adjacent conductors so as accurately to determine the spacing between adjacent conductors, and the spacer yarns are relative incompressible. The cable enables spacing of conductors to be achieved accurately enough to be used with an IDC.

Description

SPECIFICATION Woven ribbon cable This invention relates to woven ribbon cable.

Flexible cables comprising multiple conductors are increasingly used in many applications in electronic and electrical products, especially in connection withcomputer or micro processor related devices. A convenient way of producing a flat ribbon of side-by-side conductors is to weave the conductors using a weaving loom employing textile yarns as the weft. Initially connections were made to such ribbon conductors by lifting each separate end of conducting wire, stripping the insulation therefrom, and making the necessary connection by soldering or other means. However, a form of connector which grips a number of insulated wires and pierces the insulation on each to make an independent connection, known as a 'IDC', is especially convenient and is therefore increasingly being used.Naturally the spacing of the conductors is critical where an IDC is employed since it is essential that each connection of the IDC is made to the correct conductor in the ribbon cable. Hitherto, woven ribbon cables have had too much lateral flexiblity to be reliably used with IDCs and the invention seeks to provide a form of woven cable improved in these respects.

According to the present invention there is provided a woven ribbon cable in which warp ways running conductors are woven with a textile yarn weft in which spacer yarns are provided between adjacent conductors so as accurately to determine the spacing between adjacent conductors, the spacer yarns being relatively incompressible.

Preferably the spacer yarns are synthetic monofilament yarns.

Preferably also the textile weft yarns employed are untwisted multifilament yarns which, in use, go 'flat' and take up very little space in a direction perpendicular to the warp.

The conductors employed will advantageously be insulated metal, e.g. copper, wires as are normally used in ribbon cable.

The employment of a monofilament spacer yarn together with a 'flat' weft yarn in the preferred embodiment of the invention ensures that the weave is extremely close and there is little or no space for the conductors to move from the desired separation even after flexing of the woven ribbon. While the spacing is primarily determined by the count of the spacer yarn, 'fine tuning' can be achieved by altering the count of the non twisted multifilament yarn employed for the weft.

Thus very accurate conductor spacing can be achieved at different values suitable for different IDC's.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a weaving diagram of one embodiment of the invention; Figure 2 is a side elevational view of a ribbon woven in accordance with Fig. 1: Figure 3 is a weaving diagram of another embodiment of the invention; and Figure 4 is a side elevational view of the ribbon of Fig. 3.

Referring to the drawings, and in particular Figs. 1 and 2, a woven ribbon cable 10 is illustrated comprising warpways running conductors 14 spaced apart by monofilament textile yarns 1 6 and held together with a weft of untwisted multifilament synthetic textile yarns 1 8. When the weft tension is of sufficient value the warps 14 and 16 are pulled closely adjacent one another and the spacings between adjacent conductors 14 are accurately determined within a tolerance acceptable for use with IDC's.

Since the total thickness of a ribbon cable is often critical, particularly in aerospace applications, it is desirable to keep this as low as possible. Figs. 3 and 4 illustrate an alternative weave pattern where this is achieved. Additional textile yarn warps 20 are employed alowing the spacer warps 1 6 to float within the weave construction thereby preventing them rising above the general level of the conductors 1 4 as is the case with the embodiment in Figs. 1 and 2. This enables the overall thickness 'X' of the ribbon cable 10 to be reduced for the same conductor diameter.

Preferably the spacers 1 6 are monofilaments of synthetic textile material such as polyamide or polyester.

The ribbon of the invention gives the conductors accurately known and constant spacing, allows the IDC's to be employed for connecting thereto.

Furthermore, one of the advantages of a woven construction is that, where required, conductors 1 4 may be 'dropped out' of the warp intermediate the ends of the finished cable 10 where intermediate connections are required allowing great fiexiblity of use.

1. A woven ribbon cable in which warpways running conductors are woven with a textile yarn weft characterised in that spacer yarns are provided between adjacent conductors so as acurately to determine the spacing between adjacent conductors, the spacer yarns being relatively incompressible.

2. A cable as claimed in claim 1 in which the spacer yarns are synthetic monofilament yarns.

3. A cable as claimed in either of claims 1 or 2 in which the textile weft yarns are untwisted multiple filament yarns which, in use, go flat and take up very little space in a direction perpendicular to the warp.

4. A cable as claimed in any one of claims 1 to 3 in which the conductors comprise

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Woven ribbon cable This invention relates to woven ribbon cable. Flexible cables comprising multiple conductors are increasingly used in many applications in electronic and electrical products, especially in connection withcomputer or micro processor related devices. A convenient way of producing a flat ribbon of side-by-side conductors is to weave the conductors using a weaving loom employing textile yarns as the weft. Initially connections were made to such ribbon conductors by lifting each separate end of conducting wire, stripping the insulation therefrom, and making the necessary connection by soldering or other means. However, a form of connector which grips a number of insulated wires and pierces the insulation on each to make an independent connection, known as a 'IDC', is especially convenient and is therefore increasingly being used.Naturally the spacing of the conductors is critical where an IDC is employed since it is essential that each connection of the IDC is made to the correct conductor in the ribbon cable. Hitherto, woven ribbon cables have had too much lateral flexiblity to be reliably used with IDCs and the invention seeks to provide a form of woven cable improved in these respects. According to the present invention there is provided a woven ribbon cable in which warp ways running conductors are woven with a textile yarn weft in which spacer yarns are provided between adjacent conductors so as accurately to determine the spacing between adjacent conductors, the spacer yarns being relatively incompressible. Preferably the spacer yarns are synthetic monofilament yarns. Preferably also the textile weft yarns employed are untwisted multifilament yarns which, in use, go 'flat' and take up very little space in a direction perpendicular to the warp. The conductors employed will advantageously be insulated metal, e.g. copper, wires as are normally used in ribbon cable. The employment of a monofilament spacer yarn together with a 'flat' weft yarn in the preferred embodiment of the invention ensures that the weave is extremely close and there is little or no space for the conductors to move from the desired separation even after flexing of the woven ribbon. While the spacing is primarily determined by the count of the spacer yarn, 'fine tuning' can be achieved by altering the count of the non twisted multifilament yarn employed for the weft. Thus very accurate conductor spacing can be achieved at different values suitable for different IDC's. The invention will be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a weaving diagram of one embodiment of the invention; Figure 2 is a side elevational view of a ribbon woven in accordance with Fig. 1: Figure 3 is a weaving diagram of another embodiment of the invention; and Figure 4 is a side elevational view of the ribbon of Fig. 3. Referring to the drawings, and in particular Figs. 1 and 2, a woven ribbon cable 10 is illustrated comprising warpways running conductors 14 spaced apart by monofilament textile yarns 1 6 and held together with a weft of untwisted multifilament synthetic textile yarns 1 8. When the weft tension is of sufficient value the warps 14 and 16 are pulled closely adjacent one another and the spacings between adjacent conductors 14 are accurately determined within a tolerance acceptable for use with IDC's. Since the total thickness of a ribbon cable is often critical, particularly in aerospace applications, it is desirable to keep this as low as possible. Figs. 3 and 4 illustrate an alternative weave pattern where this is achieved. Additional textile yarn warps 20 are employed alowing the spacer warps 1 6 to float within the weave construction thereby preventing them rising above the general level of the conductors 1 4 as is the case with the embodiment in Figs. 1 and 2. This enables the overall thickness 'X' of the ribbon cable 10 to be reduced for the same conductor diameter. Preferably the spacers 1 6 are monofilaments of synthetic textile material such as polyamide or polyester. The ribbon of the invention gives the conductors accurately known and constant spacing, allows the IDC's to be employed for connecting thereto. Furthermore, one of the advantages of a woven construction is that, where required, conductors 1 4 may be 'dropped out' of the warp intermediate the ends of the finished cable 10 where intermediate connections are required allowing great fiexiblity of use. CLAIMS

1. A woven ribbon cable in which warpways running conductors are woven with a textile yarn weft characterised in that spacer yarns are provided between adjacent conductors so as acurately to determine the spacing between adjacent conductors, the spacer yarns being relatively incompressible.

2. A cable as claimed in claim 1 in which the spacer yarns are synthetic monofilament yarns.

3. A cable as claimed in either of claims 1 or 2 in which the textile weft yarns are untwisted multiple filament yarns which, in use, go flat and take up very little space in a direction perpendicular to the warp.

4. A cable as claimed in any one of claims 1 to 3 in which the conductors comprise insulated copper wires.

5. A woven ribbon cable substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.