GB1586194A

GB1586194A - Electric cable anchoring

Info

Publication number: GB1586194A
Application number: GB3713777A
Authority: GB
Original assignee: Standard Telephone and Cables PLC
Current assignee: STC PLC
Priority date: 1977-09-06
Filing date: 1977-09-06
Publication date: 1981-03-18
Also published as: FR2402326A1; JPS5463291A

Description

(54) ELECTRIC CABLE ANCHORING (71) We, STANDARD TELEPHONES AND CABLES LIMITED, a British Company of 190 Strand, London W.C.2., England, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to electric cable terminations, particularly the termination of a submarine cable to a repeater housing.

Our co-pending application No. 19218/77 (Serial No. pending) describes a cable termination in which there is provided a cone which has a circumferential radius and decreasing taper at one end and a bell mouth with increasing radius at the other end. This facilitates in a simple manner the anchoring of the armour wires of the cable around the cone and also limits bending of the cable in the immediate vicinity of the repeater housing. In that arrangement the armour wires are taken around the "cone" and become clamped between the cone and the annular clamping ring.

It is an object of the present invention to further simplify the anchoring arrangement while at the same time improve its reliability.

According to the present invention there is provided a cable anchor assembly whereby an electric cable can be anchored to a structure, the assembly comprising a tear-shaped anchor member with a hole through it along the major axis, a surface groove in the anchor member in which anchor wires can be located, and an insulating crush-resistant flexible shroud extending from the more pointed end of the member and coaxial therewith, wherein the assembly can be placed over a cable, with the cable passing into the shroud, and secured to the cable with anchor wires which firmly embrace the cable and pass around the groove, the anchor member being securable to the structure.

According to a further aspect of the present invention there is provided a method of anchoring an electric cable to a structure comprising providing an anchor assembly including a tear-shaped anchor member with a hole through it along the major axis, a surface groove in the anchor member in which anchor wires can be located and an insulating crush-resistant flexible shroud extending from the more pointed end of the member and coaxial therewith, passing the cable into the shroud, securing the anchor assembly to the cable with anchor wires which firmly embrace the cable and pass around the groove, and securing the anchor member to the structure, whereby tensile load in the main cable will be transferred to the anchor member.

In order that the invention can be clearly understood reference will now be made to the accompanying drawings in which: Fig. 1 shows, partially in cross-section, a cable termination according to an embodi ment of the invention, Fig. 2 shows, on an enlarged scale and in cross-section part of the embodiment of the Fig. 1, Fig. 3 shows a detail of Figs. 1 and 2 and, Fig. 4 shows a further detail of Figs. 1 and 2.

Referring to Fig. 1 a light-weight submarine main coaxial cable 1 is anchored to clamping plates 2 and 3. Plate 2 can be secured to a submarine repeater housing (not shown). At a distance from the clamping plates the coaxial cable 1 is electrically terminated as indicated at 4 and connected with a smaller more flexible waterproof tail coaxial cable 5 which extends into the repeater housing via a watertight bulkhead (all not shown).

The cable 5 and the termination 4 is shrouded in a polyethylene shroud 6 which is bonded to an internal recess 7 in a tearshaped anchoring cone 8. The recess 7 is in the form of a stepped bore, the smaller part of which houses a protective bush 9.

The coaxial cable 1 has a central strength member 10 (Fig. 2) and the tensile strain in the cable is transferred from the central strength member 10 to external wires 11.

These wires are laid around the outer plastics sheath of the cable 1 and extend around the tear-shaped cone 8 in a surface groove 12 formed thereon (Fig. 3). The wires are in the form of a cable stopper 13 (Fig. 4) with the looped end 14 placed over the cone 8 and the pre-formed limbs criss-crossing over the termination 4 and back along the cable.

This cable stopper effectively grips and clamps the sheath and prevents it slipping so that tensile forces in the coaxial cable 1 are transferred to the cone 8.

Referring to Fig. 2 the shroud 6 is bonded into the recess 7 of the cone 8 by means of epoxy resin and circumferential grooves such as 15 in the cone and in the shroud assist the epoxy resin locking the shroud to the cone. Fig. 3 shows in greater detail the cone and the groove in which are located the armour wires and the end loop 14 of the or each cable stopper. Bores such as 16 in opposite sides of the cone are provided in order that when the cable is attached to the cone the assembly can be hauled into position.

It should be pointed out that the distance between the beginning of the taper on the termination 4 and the neck of the cone 8 would be of the order of 6 inches or more and that portion of cable will be more flexible than the lightweight cable proper the other side of the termination. It is also pointed out that the Fig. 4 showing a cable stopper wire 13 is in simplified form. In practice there would be eight such wires bonded together along their length except for the bite or loop portion 14. These wires are sprayed and bonded with neoprene and carborumdum grit embedded in the neop rene in order to ensure maximum grip. The stopper can be applied to the cable by hold ing the parted end limbs 13 and snapping them over the cable. This normally requires two men and the normal length of a cable stopper is approximately 9 feet.

Referring again to Fig. 2 of the drawing the steps in the anchoring procedure are as follows. Firstly the cone 8 is provided. This can be machined from solid, or cast or forged to the required shape. Then from a solid rod or bar of polythene the polyethylene shroud 6 is machined and this is then bonded into the cone by means of epoxy resin. The main coaxial cable 1 is terminated into the tail coaxial cable with a termination 4 formed therebetween. Then the cone with the shroud bonded to it is introduced into the eye or loop 14 of the cable stopper 13 and the limbs of the cable stopper are separated. The tail cable 5 is threaded through the shroud 6 and cone 8 so that the termination 4 is positioned within the shroud 6 with the tail cable 5 extending out of the cone. Then the limbs of the cable stopper are snapped back over the main cable 1 and are secured at intervals with "bandit" strapping or other circular clamping devices.

It is to be noted that the polyethylene shroud 6 protects the termination from being crushed by the cable stopper 13 which clamps the shroud and the cable sheath tightly.

WHAT WE CLAIM IS: 1. A cable anchor assembly whereby an electric cable can be anchored to a structure, the assembly comprising a tear-shaped anchor member with a hole through it along the major axis, a surface groove in the anchor member in which anchor wires can be located, and an insulating crush-resistant flexible shroud extending from the more pointed end of the member and coaxial therewith, wherein the assembly can be placed over a cable, with the cable passing into the shroud, and secured to the cable with anchor wires which firmly embrace the cable and pass around the groove, the anchor member being securable to the structure.

2. A method of anchoring an electric cable to a structure comprising providing an anchor assembly including a tear-shaped anchor member with a hole through it along the major axis, a surface groove in the anchor member in which anchor wires can be located and an insulating crush-resistant flexible shroud extending from the more pointed end of the member and coaxial therewith, passing the cable into the shroud, securing the anchor assembly to the cable with anchor wires which firmly embrace the cable and pass around the groove, and securing the anchor member to the structure, whereby tensile load in the cable will be transferred to the anchor member.

3. A method as claimed in claim 2, wherein the cable is terminated into a tail cable via a relatively flexible cable portion, the tail cable extending through the anchor member with the flexible cable portion positioned within the shroud.

4. An anchor or method substantially as hereinbefore described with reference to and as illustrated in the accompanying drawinns.

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

Claims

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

12 formed thereon (Fig. 3). The wires are in the form of a cable stopper 13 (Fig. 4) with the looped end 14 placed over the cone 8 and the pre-formed limbs criss-crossing over the termination 4 and back along the cable.

This cable stopper effectively grips and clamps the sheath and prevents it slipping so that tensile forces in the coaxial cable 1 are transferred to the cone 8.

Referring to Fig. 2 the shroud 6 is bonded into the recess 7 of the cone 8 by means of epoxy resin and circumferential grooves such as 15 in the cone and in the shroud assist the epoxy resin locking the shroud to the cone. Fig. 3 shows in greater detail the cone and the groove in which are located the armour wires and the end loop 14 of the or each cable stopper. Bores such as 16 in opposite sides of the cone are provided in order that when the cable is attached to the cone the assembly can be hauled into position.

It should be pointed out that the distance between the beginning of the taper on the termination 4 and the neck of the cone 8 would be of the order of 6 inches or more and that portion of cable will be more flexible than the lightweight cable proper the other side of the termination. It is also pointed out that the Fig. 4 showing a cable stopper wire 13 is in simplified form. In practice there would be eight such wires bonded together along their length except for the bite or loop portion 14. These wires are sprayed and bonded with neoprene and carborumdum grit embedded in the neop rene in order to ensure maximum grip. The stopper can be applied to the cable by hold ing the parted end limbs 13 and snapping them over the cable. This normally requires two men and the normal length of a cable stopper is approximately 9 feet.

Referring again to Fig. 2 of the drawing the steps in the anchoring procedure are as follows. Firstly the cone 8 is provided. This can be machined from solid, or cast or forged to the required shape. Then from a solid rod or bar of polythene the polyethylene shroud 6 is machined and this is then bonded into the cone by means of epoxy resin. The main coaxial cable 1 is terminated into the tail coaxial cable with a termination 4 formed therebetween. Then the cone with the shroud bonded to it is introduced into the eye or loop 14 of the cable stopper 13 and the limbs of the cable stopper are separated. The tail cable 5 is threaded through the shroud 6 and cone 8 so that the termination 4 is positioned within the shroud 6 with the tail cable 5 extending out of the cone. Then the limbs of the cable stopper are snapped back over the main cable 1 and are secured at intervals with "bandit" strapping or other circular clamping devices.

It is to be noted that the polyethylene shroud 6 protects the termination from being crushed by the cable stopper 13 which clamps the shroud and the cable sheath tightly.

WHAT WE CLAIM IS: 1. A cable anchor assembly whereby an electric cable can be anchored to a structure, the assembly comprising a tear-shaped anchor member with a hole through it along the major axis, a surface groove in the anchor member in which anchor wires can be located, and an insulating crush-resistant flexible shroud extending from the more pointed end of the member and coaxial therewith, wherein the assembly can be placed over a cable, with the cable passing into the shroud, and secured to the cable with anchor wires which firmly embrace the cable and pass around the groove, the anchor member being securable to the structure.
2. A method of anchoring an electric cable to a structure comprising providing an anchor assembly including a tear-shaped anchor member with a hole through it along the major axis, a surface groove in the anchor member in which anchor wires can be located and an insulating crush-resistant flexible shroud extending from the more pointed end of the member and coaxial therewith, passing the cable into the shroud, securing the anchor assembly to the cable with anchor wires which firmly embrace the cable and pass around the groove, and securing the anchor member to the structure, whereby tensile load in the cable will be transferred to the anchor member.
3. A method as claimed in claim 2, wherein the cable is terminated into a tail cable via a relatively flexible cable portion, the tail cable extending through the anchor member with the flexible cable portion positioned within the shroud.
4. An anchor or method substantially as hereinbefore described with reference to and as illustrated in the accompanying drawinns.