A wiring harness comprises a number of physically connected wires for use in electro mechanical engineering applications, such as automotive or aeronautical wiring systems. In order to support the wiring harness in a machine a series of'P'clips are used. A'P'clip comprises a metal shaft.

A ribbon of metal is looped and the ends of the loop clamped to one end of the metal shaft. The interior surface of the looped metal ribbon is lined with a band of rubber. The other end of the metal shaft is adapted to receive a bolt.

In use the'P'clips are bolted to a mechanically substantial component such as an engine or gearbox and the wiring harness threaded through the loops formed by the ribbons of metal. The rubber interior of the loop protects the wiring harness from frictional damage that would be caused by the wire harness rubbing against the metal loop.

'P'clips are used extensively in the aeronautics industry to attach wire harnesses to aero engines. In this application the wiring harnesses are subjected to external electric fields.

This means of securing wiring harnesses in place suffers from the drawback that the wiring harness and harness clips are separate entities; thus provision must be made to prevent the clip and harness rubbing together and causing frictional damage on the harness. These provisions

increase the cost of manufacture of wiring harness systems.

It would be desirable to provide a means of securing the wiring harness in place that would alleviate the need to provide protection against frictional damage in the wiring harness. This would lead to a reduction in production costs.

The present invention has been made from a consideration of this problem.

According to the present invention there is provided a wiring harness characterised in that the wiring harness comprises at least one integral harness clip to be used in securing the wiring harness to another body.

Thus, the harness clip is secured to the wiring harness prior to the harness being secured to the other body. The harness preferably comprises a plurality of clips.

The clip preferably comprises a plurality of arms. The clip may be formed from a flat plate. Alternatively one or more arms of the clip could comprise channel sections, this can help protect wires running in the harness. The clip preferably has rounded edges.

At least one arm of the clip preferably includes an aperture so that the harness clip may be connected to a support by a nut and bolt connection, via the aperture, by threading a bolt through the aperture.

Other suitable fastening means could also be employed, for example quick release fasteners.

In one embodiment of the invention the harness clip is substantially T-shaped. In this embodiment the harness clip possess three arms, two of which are substantially aligned and one which is perpendicular to the other two.

In the T shaped arrangement of the harness clip it is preferred that the arm perpendicular to the other two aligned arms possess an aperture.

The harness clip could have four arms in a substantially cross shaped arrangement. It will be apparent, however, that it is possible to use any shape of harness clip for a particular application if a standard fitting is not suitable.

The harness clip may be provided at any point in the harness. If the clip is provided where the harness is divided into branches it is desirable that the harness clip has an arm for each branch of the harness. The clip can thus add strength to the harness at the branching point.

The harness preferably includes an electrical over-screen to protect the harness from electro-magnetic effects and, in particular, electro- magnetic compatibility problems. The over-screen preferably comprises metal braiding or foil. The over-screen preferably extends throughout the harness.

To further enhance protection afforded from electromagnetic effects each clip is preferably electrically conductive and in electrical contact with the electrical over-screen. Thus, when the harness is mounted on another

body each clip may serve as an earth bonding point.

Preferably an arm of the harness clip is secured to the electrical over- screen by a wrap, for example a stainless steel wire or foil wrap, wound around the over-screen. As such, part of the electrical over-screen is sandwiched between the harness clip and remainder of the harness.

The harness is preferably encapsulated in an over-sleeve. The over- sleeve preferably comprises a conventional thermofit over-sleeve produced from a plastics or rubber material. Encapsulating the harness prevents contamination and hence degradation of wires running in the harness. Of course, part of the clip must be accessible to enable the harness to be secured to another body. To maintain encapsulation integrity, therefore, it is preferred that the over-sleeve is bonded to the clip with an adhesive seal.

Where a sleeve is provided it is preferred that the clip has rounded edges or is otherwise profile to reduce the risk of damage to the sleeve.

Preferably the adhesive seal is a'Raychem S1125'adhesive seal or some other compatible epoxy adhesive seal.

Preferably the harness clip is manufactured from metal, for example stainless steel or aluminium. Electrically conductive, or other, plastics could also be used.

In order that the present invention may be more readily understood specific embodiments thereof will now be described with reference to the accompanying drawings in which:-

Figure 1 is a part cut away perspective view of a part of a wiring harness according to the invention; Figure 2 is a cross-sectional view taken along the line II-II of Figure 1; Figure 3 is a plan view of the clip of the harness shown in Figure 1; Figure 4 shows an alternative type of clip; Figure 5 shows a further alternative type of clip; and Figure 6 shows a still further alternative type of clip.

Referring to Figures 1 to 3 a wiring harness comprises a number of harness sections 10 and a harness clip 12. The harness clip 12 comprises a flat aluminium generally cross-shaped body having four arms disposed substantially at right angles to each other. One of the arms is shorter than the other three and has an aperture formed therethrough.

The harness sections comprise cables which, in turn, comprise wires 16 which are grouped together by plastics protective sleeves 18.

A woven braided metal sleeve 20 is wrapped around the cables. The braided sleeve 20 provides protection from electromagnetic effects and runs throughout the harness.

A thermofit protective over-sleeve 22 is disposed over the braided metal sleeve 20. The sleeve 22 is heat shrunk over the braided sleeve 20.

Such sleeves and their method of use are well known and will therefore not be described further. The over-sleeve 22 encapsulates the harness and thus reduces the risk of contamination of the harness when used in polluted

environments. In particular, it enables the harness to be washed to remove contaminants whilst preventing contact between water or other washing solutions and the encapsulated wiring. This is a particularly important feature for harnesses employed in military aircraft engines.

The harness splits into a number of minor branches 24. Each branch includes one or more cables comprising bundles of wires surrounded by a sleeve, a braided sleeve and an outer thermofit sleeve.

The clip 12 is disposed so that it lies in contact with the braided sleeve 20 of the main branch of the illustrated harness to which it is secured by means of a stainless steel wrap 26. The clip 12 is tightly bound to the braided sleeve 20 with the wrap 26 to ensure there is good electrical contact between the clip 12 and sleeve 20. The wrap 26, being electrically conductive, also aids in establishing electrical contact between the clip 12 and sleeve 20. The clip 12 therefore provides an earthing point for the sleeve 20.

The remainder of the clip 12 overlies the over-sleeve 28 of a minor branch of the harness. The outer sleeve 22 of the main branch of the harness overlies part of the clip 12, wrap 26 and over-sleeve 28 of the other branch.

An adhesive seal 30 is disposed between the outer sleeves 22,28 of the branches and the clip 26 and outer sleeve 22. Additional, short, over- sleeves 31 are disposed over the arms of the clip which lie over the outer

sleeves 28 of the minor branches 24. Alternatively wraps such as used on the main branch could be employed.

The harness clip may be attached to a load bearing component on an aero engine, or other equipment, using a suitable fastener, for example a nut and bolt, passed through the aperture 14. This allows the wiring in the aero engine to be mounted securely in its correct position. The clips may then act as electrical earth bonding points to dissipate any static electricity, for example when the wiring harness is subjected to an external electric field.

Referring to Figures 4 and 5 there are shown two alternative forms of clip. Figure 4 shows a clip with six arms two of which include apertures.

It is suitable for incorporation into a wiring harness with four branches.

Figure 5 shows a clip with three arms one of which includes an aperture.

It is suitable for incorporating along a single branch of a wiring harness.

A clip possessing any number of arms with any angular spacing between the arms may be used if such is required, for example for use in a particularly cramped area of the aero engine.

Referring to Figure 6 there is shown a clip of similar design to that shown in Figure 3, except for the provision of an integral clamp band 32 on one of the arms. This band may be bent around the braided sleeve of a harness to secure the clip thereto and provide good electrical contact between clip and harness. Provision of a clamp band obviates the need for

a separate wrap to secure the clip to a harness.

Of course, the drawings only show a part of a wiring harness. A typical harness would comprise many harness sections, branches and clips.

The above embodiments are described by way of illustration only.

Many modifications and variations are possible. For example, in an alternative arrangement the arms of a harness clip may be disposed under the braided sleeve of a harness. Also, the bundles of wires forming each cable could simply be retained by the electrically conductive braided sleeve.