Patent Description:
The invention also relates to an assembled cable.

The invention relates more particularly to a method for manufacturing assemblies, each of which comprises at least one multicore cable and a connector, which are also called assembled cables.

Assemblies of this type are notably used in the defence, aeronautical or medical equipment industry.

An assembly mainly consists of a set of components, including a connector that provides an interface with a complementary connector and a multicore cable enabling the transmission of signals and/or electric currents, for example for communication, data exchange and/or electric power supply.

A multicore cable may be an electric cable, comprising only electrical conductors (for example in the form of electrical wires), or else a so-called "hybrid" cable comprising at least one electrical conductor and at least one optical conductor (for example in the form of an optical fibre).

An associated or complementary connector may be an electrical connector for an electric multicore cable, or a hybrid connector for a hybrid multicore cable.

For a strong, reliable joint, an assembled cable also comprises other components, and notably a rear connector, which is screwed on the rear portion of the connector to which the various conductors of the multicore cable are connected.

This connector notably makes it possible to ensure electrical continuity between metallic peripheral braid shielding the multicore cable - also called "earthing", and thus electrical continuity of earthing with another assembled cable or electrical and/or electronic equipment. Such an arrangement is known for example from documents <CIT> and <CIT>.

The mechanical joint between the multicore cable and the connector - ensuring tensile strength of the joint between the multicore cable and the connector - may be provided by an external heat-shrinkable cap.

A heat-shrinkable cap of this kind can also guarantee hermeticity of the joint between the multicore cable and the connector in addition by making use of a kit for a two-component adhesive, to guarantee hermeticity of the heat-shrinkable cap, during production and execution of this joint.

For a whole range of applications, notably corresponding to the special environments mentioned above, the connectors used comply with the "MIL" or "MIL-SPEC" standards. We may mention, as non-limiting examples, the connectors belonging to the categories MIL-C-<NUM> series I&II and III&IV, MIL-C-<NUM>, or MIL-C-<NUM>.

Thus, for a given connector corresponding to a MIL standard, production of a connector-multicore cable basic assembly requires collecting together various compatible components or elements, then assembling them by carrying out a set of manual operations, none of which can be automated.

Selection of the components to be assembled is a complex operation, as too are the operations of assembly and manufacture.

Each assembly of this type is thus produced by selecting components from five catalogues corresponding to:.

Besides this large number of possible combinations (more than twenty thousand combinations for four different connectors), it is very difficult, for the assembler and manufacturer of the assembled cable, to guarantee constant, accurate shape and dimensions, with the risk that this leads to defects of aesthetic and/or dimensional compliance.

The invention aims to propose a novel method of manufacture and a novel assembly, which overcome the main drawbacks that have just been mentioned.

The invention proposes a method for manufacturing an assembly consisting of a connector and a multicore cable that comprises:.

wherein the method consists, successively, of:.

According to other optional features of the method:.

The invention also proposes an assembly comprising:.

According to other optional features of the assembly:.

Other features and advantages of the invention will become clearer on reading the detailed description given hereunder, for understanding of which reference will be made to the appended drawings, where:.

In the rest of the description, elements having an identical structure or similar functions will be denoted by the same references.

In the rest of the description, axial or longitudinal orientations will be adopted in a non-limiting manner with reference to the general axial direction of the multicore cable and its associated connector, and radial or transverse orientations relative to this longitudinal / axial direction.

An axial orientation is also defined from back to front, from right to left correspondingly with reference to <FIG>.

<FIG> shows an assembled cable <NUM>, the components of which are shown in detail in <FIG>.

The assembled cable <NUM> comprises a connector <NUM>, which in this case is an electrical connector, and a multicore cable <NUM>, which in this case is an electric cable.

The multicore cable <NUM> comprises a plurality of electrical conductors <NUM>, each with its own insulating outer sheath <NUM>, and which are surrounded by a peripheral metallic shielding braid <NUM>, which is electrically conductive.

On its whole length, the multicore cable <NUM> is surrounded by an outer protective sheath <NUM>, which is a sheath made of impervious plastic.

As can be seen, notably in <FIG>, with a view to jointing with the connector <NUM>, the front portion of the multicore cable <NUM> was prepared by removing a free front end portion of the outer protective sheath <NUM> and a free front end portion of the peripheral metallic braid <NUM>.

Each conductor <NUM> comprises a free front end <NUM> - shown schematically in <FIG> - which is configured to allow jointing thereof with the complementary rear portion of the connector <NUM>, for example by axial insertion of this front end <NUM> into a complementary socket (not shown) opening into the rear face of the connector <NUM>.

For example, the ends <NUM> of the electrical conductors <NUM> may be equipped with crimped contacts, which are then plugged into the connector <NUM>.

The principles of the invention are independent of the technique for jointing the electrical and optical conductors to the connector.

The rear portion <NUM> of the connector <NUM> is an electrically conductive portion, which is configured here as a cylindrical socket.

In a "MIL" standard or standardized connector of this type, the rear portion <NUM> of the connector <NUM> is threaded externally to receive a screwed joint of the type mentioned at the beginning, which can notably provide earthing between the metallic shielding braid <NUM>, and thus electrical continuity of earthing with another assembled cable or electrical and/or electronic equipment.

The components illustrated in <FIG> further comprise an intermediate ring <NUM> and a radial clamping collar <NUM>.

The intermediate ring <NUM> is a metallic and/or electrically conductive ring, which is threaded internally so that it can be screwed onto the threaded rear portion <NUM> of the connector <NUM>.

To make it easier to screw on, the periphery of the intermediate ring <NUM> is knurled.

The clamping collar <NUM> is of known general design and it may be metallic or insulating.

The first step of manufacture of the assembled cable <NUM> illustrated in <FIG> comprises, as illustrated in <FIG>, the operations consisting of:.

The order of the above operations is not limiting.

In the situation illustrated in <FIG>, there is a region "Z" in which the conductors <NUM> are free and visible, said region Z extending axially, along the longitudinal axis "A" of the connector <NUM>, between the front end edge <NUM> of the outer sheath <NUM> over which the shielding braid <NUM> is folded, and the rear end edge <NUM> of the intermediate ring <NUM>.

Starting from the situation illustrated in <FIG>, the method of manufacture then consists of moulding a first material <NUM>, which is for example a plastic, around the conductors <NUM>.

The moulding operation is for example carried out in a first cavity of a mould (not shown), for example according to a moulding technique such as injection moulding.

Thus, a first overmoulding <NUM> is produced, of cylindrical general shape, which extends axially between the front end edge <NUM> of the outer sheath <NUM> over which the shielding braid <NUM> is folded, and the rear end edge <NUM> of the intermediate ring <NUM>, moreover the first material <NUM> may extend axially forwards into the intermediate ring <NUM>, as far as the rear face of the connector <NUM>.

The first material <NUM> may also extend between the conductors <NUM> in such a way that the first overmoulding is "full".

The first moulding may be "low-pressure" moulding, notably when we wish to avoid damaging the conductors <NUM> and the jointing of their free ends <NUM> to the connector <NUM>.

Starting from the situation illustrated in <FIG>, the method of manufacture then consists of unfolding or pulling forwards the front portion of the shielding braid <NUM> that was previously folded back, over the portion facing the outer sheath <NUM>.

Thus, the free front end section <NUM> of the shielding braid <NUM> extends at least partly over the knurled outside surface of the intermediate ring <NUM>.

As a result, electrical continuity has been established between the shielding braid <NUM> and the intermediate ring <NUM>, and therefore between the shielding braid <NUM> and the connector <NUM>.

The free front end section <NUM> of the shielding braid <NUM> is clamped radially around the intermediate ring <NUM> by means of the clamping collar <NUM>, illustrated in its free, unclamped state in <FIG>.

The clamping collar <NUM> is an element providing radial clamping, which on the one hand guarantees high quality of electrical contact between the shielding braid <NUM> and the intermediate ring <NUM> and which, on the other hand, contributes to good mechanical holding of the shielding braid <NUM> in position before the next step.

Starting from the situation illustrated in <FIG>, the method of manufacture then consists of making an outer envelope <NUM> by moulding a second material <NUM>, which is for example a plastic.

The moulding operation is for example carried out in a second cavity of a mould (not shown), for example according to a moulding technique such as injection moulding.

A second overmoulding <NUM> is thus produced, of cylindrical general shape.

This second overmoulding forms an outer envelope <NUM>, which extends axially backwards, to cover the front portion of the outer protective sheath <NUM> delimited by the front end edge <NUM>.

Thus, the rear portion of the overmoulding <NUM> covers a free front end section of the outer sheath <NUM>, with which it interacts imperviously.

At the front, notably to provide protection and hermeticity, the second overmoulding forming the outer envelope <NUM> extends axially so as to surround the shielding braid <NUM> completely.

Thus, the shielding braid <NUM> is surrounded and covered by the second moulding material <NUM> on its entire axial length between its front free end edge and the front end edge <NUM> of the outer sheath <NUM>.

The second moulding material <NUM> covers and takes on the shape of the metallic shielding braid.

It may also extend axially forwards over the whole of the intermediate ring as far as the rear face of the connector <NUM>.

The second moulding, made around the first moulding <NUM>, interposing the shielding braid <NUM>, may be a "high-pressure" moulding, notably to endow the outer envelope <NUM> with great rigidity and accuracy of form(s) and dimension(s).

Provided a first moulding <NUM> has already been carried out, application of a "high-pressure" moulding technique does not present a risk of deterioration of the conductors <NUM> and of their joints.

In the embodiment example illustrated in <FIG>, the second mould cavity is a shaping cavity, which endows the assembly with an overall rectilinear configuration and a rectilinear final relative orientation of the connector <NUM> relative to the general axis of the front portion of the multicore cable <NUM> that is joined to the connector <NUM>.

The second embodiment example illustrated in <FIG> only differs from the first example by the "angled" configuration - in this case at an angle of <NUM> degrees - of the front portion of the multicore cable <NUM> that is joined to the connector <NUM>.

By selecting the profile of the mould cavities used for the various moulding operations, the method according to the invention makes it possible to produce all possible orientations as well as all shapes and external profiles of the outer envelope <NUM>.

According to the embodiment described above, the clamping collar <NUM> is the device that provides radial clamping of the braid that guarantees the quality of electrical contact and that contributes to good mechanical durability of the shielding braid.

Claim 1:
Method for manufacturing an assembly (<NUM>) consisting of a connector (<NUM>) and a multicore cable (<NUM>) that comprises:
* a multicore cable (<NUM>) comprising conductors (<NUM>) including at least one electrical conductor (<NUM>), a peripheral metallic shielding braid (<NUM>) that surrounds the conductors (<NUM>), and an outer protective sheath (<NUM>);
* a connector (<NUM>) to which the front ends (<NUM>) of the conductors (<NUM>) of the multicore cable (<NUM>) are connected, and which comprises a conductive rear portion (<NUM>, <NUM>) to which the free front end section (<NUM>) of the shielding braid (<NUM>) is connected electrically,
wherein the method consists, successively, of:
- jointing the front free ends (<NUM>) of the conductors (<NUM>) to the connector (<NUM>);
- folding back a front portion of the shielding braid (<NUM>);
- moulding a first material (<NUM>, <NUM>) at least around the conductors (<NUM>), in a region (Z) not surrounded by the folded-back shielding braid (<NUM>);
- screwing a conductive intermediate jointing ring (<NUM>) onto the conductive rear portion of the connector (<NUM>) which is an externally threaded portion;
- unfolding said front portion of the shielding braid over said region (Z) to bring a front section (<NUM>) of the shielding braid into electrical contact with the conductive rear portion (<NUM>, <NUM>) of the connector (<NUM>);
- clamping the front section (<NUM>) of the shielding braid (<NUM>) radially around the ring (<NUM>) of the connector (<NUM>);
- moulding a second material (<NUM>) to constitute an outer envelope (<NUM>) of the assembly (<NUM>) that surrounds at least the shielding braid (<NUM>) from its front free end (<NUM>) to a front portion of the outer sheath (<NUM>) of the multicore cable surrounding the shielding braid (<NUM>).