This invention relates to protection of cables. In particular, the invention relates to a cable protector, a cable protection arrangement and to a method of protecting a cable. BACKGROUND OF THE INVENTION

Cables that contain metals such as Copper, Aluminium and other metals are sometimes vulnerable to theft. Methods used to conduct cable theft operations include cutting the cables and ripping them from overhead masks or from underground conduits.

This invention aims to address this problem.

SUMMARY OF THE INVENTION

According to one aspect of the invention, there is provided a cable protector, which includes

at least two cable connectors, each defining a cable-receiving zone operatively extending co-axially with a cable on which the cable protector is to be mounted, the cable connectors being mechanically connectable to two adjacent cables, the cable connectors each having gripping means for gripping onto the cables;

an isolated interconnection member connected to the at least two cable connectors for retaining the cable connectors together; and an articulation joint disposed between each of the cable connectors and an end of the interconnection member to permit articulation between the connector and the interconnection member. The isolated interconnection member may be capable of withholding a tensile strength exerted thereon when a cable to which it is connected is severed.

In a normal state, the interconnection member may extend transversely from the cable-receiving zone. In use, when a cable is cut the cable connectors may be urged apart by the recoil force of the cables forcing the interconnection member to extend substantially parallel with the two cables, being permitted thereto by the articulation joints between the cable connectors and the interconnection member. In this specification, the term "normal state" refers to the state in which the interconnection member is installed onto two adjacent cables and refers to an unstressed state of the interconnection member. In use, when a cable is cut, the interconnection member operates in a "stressed state" in which the at least two cable connectors grip onto the cables in the cable receiving zones, being held together by the isolated interconnection member under tensile stress induced by the recoil force of at least one of the cables.

The articulation joint may permit movement of the isolated interconnection member in a plane defined between two adjacent cables. The gripping means may be self-locking, thereby to automatically grip onto the cable when a cable onto which the cable connector is mechanically connected is severed and the isolated interconnection member no longer extends transversely form the cable-receiving zone and operates in a stressed state. The isolated interconnection member may include isolators between the at least two cable connectors to prevent ionisation and arc-over between the two cable connectors. The interconnection member may be stiff to retain the spacing between the cable connectors. Alternatively the interconnection member may be flexible to permit relative movement between the cable connectors.

In one embodiment of the invention at least one of the at least two cable connectors may include

a clamp, having a washer receiving slot extending transversely to the cable-receiving zone; and

gripping means defined by a split washer receivable into the transverse washer receiving slot of the clamp.

In this embodiment the cable-receiving zone may be defined by an aperture in the washer.

The split washer may be bent open to allow a cable to be received within the centre circular aperture of the washer. When a force is exerted on the cable, the washer may twist on the cable and operates in a stressed state, thereby gripping onto the cable and preventing movement between the grip and the cable along the length of the cable. In this embodiment the clamp may include receiving zones, for receiving the articulation joint.

In another embodiment at least one of the at least two cable connectors may be defined by two open-cylindrical shaped members having tapered bores co-axial with the cable-receiving zone. In this embodiment the gripping means may be in the form of wedges receivable into the tapered bores. The wedges may be arranged circumferentially around the cable-receiving zone for gripping onto the cable. The wedges may define an inner cylindrical passage into which a cable is receivable, the passage defining the cable-receiving zone.

The wedges in the tapered bore of one open-cylindical shaped members may be oppositely arranged to the wedges in the tapered bore of the other open-cylindical shaped member, the wedges of the two open-cylindical shaped members thereby acting in opposing directions, in use when a cable is cut on either side of the cable connector, the coiling action of the cable will cause one of the sets of wedges to engage the cable to prevent it from being withdrawn from either side of the cable connector. In yet a further embodiment of the invention, at least one of the at least two cable connectors may be in the form of a U-shaped member, having an opening for receiving the cable into the cable receiving zone which is defined inside the U-shaped member. The cable connector may be provided with a closing member arranged to close an open side of the U-shaped member once a cable is received into the cable-receiving zone. When a force is exerted on the cable, the cable connector twists on the cable and operates in a stressed state, thereby gripping onto the cable and preventing movement between the cable connector and the cable along the length of the cable.

According to another aspect of the invention there is provided a cable protection arrangement, which includes

at least one cable protector as described installed onto at least two adjacent cables. The invention extends to a method of protecting a cable, which includes

installing a cable protector into at least two adjacent cables. The invention will now be described, by way of example only with reference to the following drawing(s):

DRAWING(S) In the drawing(s):

Figure 1 shows a three dimensional view of one embodiment of a cable protector in accordance with the invention;

Figure 2 shows the cable protector of Figure 1 installed onto two adjacent cables;

Figure 3 shows a sectional view at line III and III;

Figures 4 and 5 show another embodiment of a cable protector in accordance with the invention;

Figure 6 show a further embodiment of a cable protector in accordance with the invention.

EMBODIMENT OF THE INVENTION

In Figures 1 and 2, a cable protector 10 is shown in three dimensions. The cable protector 10 includes two cable connectors 12, 14.

The cable connectors in this example are each defined by two open-cylindrical shaped members 16, 18 and 21 , 23 (not visible in Figurel ) respectively. Each member 16, 18 and 21 , 23 has a tapered centre opening 16.1 , 18.1 , 21.1 , 23.1 (not visible) and is shaped and dimensioned to receive a cable. The centre openings 16.1 , 18.1 , 20.1 , 22.1 are in the form of tapered bores and define cable receiving zones operatively extending co-axially to a cable, when in use. The bores of the pairs of members 16, 18 and 21 , 23 are oppositely tapered towards the operative outer direction.

In this example the gripping means is in the form of wedges receivable into the tapered bores. Each member 16, 18, 21 , 23 includes a set of four wedges 16.2 to 16.5, 18.2 to 18.5, 21.2 to 21.5 (not visible) and 23.2 to 23.5 (not visible) respectively, arranged circumferentially inside the tapered bores 16.1 , 18.1 , 21.1 (not visible), 23.1 (not visible). The wedges 16.2 to 16.5, 18.2 to 18.5, 21.2 to 21.5 (not visible) and 23.2 to 23.5 (not visible) are all elongated, wedge shaped and extend coaxial to the cable-receiving zones 16.1 , 18.1 , 21.1 , 23.1. The wedges 16.2 to 16.5, 18.2 to 18.5, 21.2 to 21.5 and 23.2 to 23.5, being in contact with a cable to be installed into the cable connectors 12, 14 and being wedge shaped in the tapered bores 16.1 , 18.1 , 20.1 , 22.1 defining self-locking grips. The grips are activated when an installed cable is jerked in either operative outer direction of the pairs of members 16, 18 and 21 , 23.

The cable protector 10 further includes an isolated interconnection member 20 connected to the two cable connectors 12, 14. The cable protector includes articulation joints 15, 17 between the interconnection member 20 and the cable connectors 12, 14. In this example, the isolated interconnection member 20 includes isolators 26, 28 between the cable connectors 12, 14 to improve the isolation properties of the protector when installed. The isolators 26, 28 will reduce the possibility of arc-over between two adjacent cables. In this example, the interconnection member 20 is stiff to retain the spacing between cables. In other examples, not shown, the interconnection member may be flexible to permit free independent movement of cables.

As can be seen in Figure 2, the cable protector 10 is installed onto two adjacent, parallel running cables 22, 24. This arrangement defines a cable protection arrangement also in accordance with the invention. The cable protector 10 is installed by clipping the cable connectors 12, 14 over the cables 22, 24. As can be seen the interconnection member 20 extends roughly transversely from the cable receiving zones 16.1 , 18.1 and 21.1 , 23.1 in the normal position. In use, when a cable 22 or 24 is cut the cable connectors 12, 14 will lock onto the cables 22, 24 by means of the wedges 16.2 to 16.5, 18.2 to 18.5, 21.2 to 21.5 and 23.2 to 23.5, being wedged into the tapered bores 16.1 , 18.1 , 21.1 , 23.1.

In use, when a cable is cut on either side of the cable connector, the coiling action of the cable will cause the cable connectors 12, 14 to lock into the cable thereby preventing it from being withdrawn from either side of the connectors 12, 14.

In Figure 4 another embodiment of the cable protector 50, is shown. The cable protector 50 includes two cable connectors of which only one is indicated as 52. The cable connector 52 is in the form of a U-shaped member 54, having an opening for receiving the cable into the cable receiving zone which is defined inside the U-shaped member 54. The cable connector 52 is provided with a closing member 56. The cable connector 52 is connected to an isolated interconnection member 58 via a hinge 59.

The U-shaped member 54 and the closing member 56 are connected to each other by means of two locking pins 60, 62. The locking pins 60, 62 protrude through apertures 54.1 , 54.2 and 56.1 (not visible), 56.2. As can be seen in Figure 5, the U-shaped member 54 and the closing member 56 lock around a cable when the pins 60, 62, are inserted through the apertures 54.1 , 54.2, 56.1 , 56.2.

In Figure 6, a cable connector 60 is shown in accordance with yet another embodiment installed on a cable 74 (shown in broken lines). In this example the cable connector 60 includes a clamp 62, having a washer receiving slot 64 extending transversely to the cable receiving-zone and gripping means defined by a split washer 66 receivable into the transverse washer receiving slot 64 of the clamp 62. The cable-receiving zone is defined by a central aperture (not shown) in the washer 66. The split washer 66 may be bent open to allow the cable 74 to be received into the aperture in the washer 66, and be re-closed thereafter to fit in the washer receiving slot 64. When a differential tensile force is exerted on the cable across the cable connector 60, the washer 66 will twist on the cable, thereby gripping onto the cable and preventing longitudinal movement of the cable 74 in the cable connector 60. In this example the clamp 62, includes apertures 68, 70 for receiving an articulation axis 72 defining an articulation joint.

It is to be appreciated that other examples of the cable protector are envisaged, all of which are covered by the present invention.

As can be seen, the installation of the cable protector 10 described provides a method of protecting a cable.

The inventor is of the opinion that the present invention, as described provides a new cable protector, a new cable protection arrangement and a new method of protecting a cable.