GB2243958A - Aerial cable separating tool - Google Patents

Abstract

A hand tool for locally separating the lobes of an aerial cable of 8-shaped transverse cross-section comprises two bodies 11 and 12 having opposed co-operating surfaces in which grooves 14 define two parallel transversely spaced passages. A coil spring 18 urges the body 12 towards the body 11 to grip loosely limited lengths of the lobes of a cable in the passages. A cutting blade 17 carried by body 12 extends parallel to the passages and can be caused to cut through the web of insulating material integral with and extending between the lobes of the cable. By moving the hand tool lengthwise with respect to the cable, a slit of limited length can be formed in the web of the 8-shaped cable. <IMAGE>

Description

AERIAL CABLE SEPARATING TOOL Known forms of electric and/or optical cables which are to be suspended in long lengths between poles or other upstanding supports disposed at spaced positions along the route of a cable installation each comprise an elongate body of extruded electrically insulating material having a transverse cross-section approximating to a figure-of-eight, wherein, in one lobe of the 8-shaped elongate body, there is embedded at least one flexible elongate reinforcing member of high tensile strength and, in the other lobe of the 8-shaped elongate body, there is embedded or disposed at least one electric conductor and/or at least one optical fibre element. For convenience, all such electric and/or optical cables will hereinafter be referred to as "aerial cables of 8-shaped transverse cross-section".

When suspending an aerial cable of 8-shaped transverse cross-section from a pole or other upstanding support or for other purposes, it is often necessary to separate locally the two lobes of the 8-shaped elongate body intermediate of the ends of the aerial cable in such a way as to maintain the integrity of each lobe.

Usually the two lobes are locally separated over a limited length of aerial cable by cutting through the web of insulating material integral with and extending between the two lobes using a sharp knife. Not only is this cutting operation hazardous to the operator but there is a serious risk that, during the cutting operation, unacceptable damage may be caused to the or an electric conductor and/or optical fibre element and/or to the or a flexible reinforcing member.

It is an object of the present invention to provide a simple and an inexpensive hand tool by means of which limited lengths of the two lobes of an aerial cable of 8-shaped transverse cross-section can be readily locally separated with negligible risk of damaging the integrity of the lobes of the cable.

According to the invention, the hand tool comprises two separately formed bodies having opposed co-operating surfaces defining two substantially parallel transversely spaced passages each of such a cross-sectional shape and size that a limited length of one of the two lobes of an aerial cable of 8-shaped transverse cross-section can be disposed therein; means for urging the two bodies together to grip loosely limited lengths of the lobes of an 8-shaped cable in the passages; and, for cutting through the web of insulating material integral with and extending between limited lengths of the two lobes of an 8-shaped cable disposed in the passages, a cutter which is disposed between the passages and which has a cutting edge constrained to extend lengthwise with respect to the passages and protruding beyond the plane containing the longitudinal axes of the passages.

By virtue of the fact that limited lengths of the lobes of an aerial cable are gripped loosely in the passages and that the cutting edge of the cutter protrudes through the plane containing the longitudinal axes of the passages, the cutting edge can be caused to effect a local cut in the web extending between the limited lengths of the two lobes of the aerial cable with negligible risk of any damage being caused to either of the lobes.

Preferably, the cutting edge of the cutter over at least one and preferably each end part of its length extends in a direction substantially normal or at an acute angle to the plane containing the longitudinal axes of the passages so that, by moving the hand tool with respect to an 8-shaped aerial cable gripped loosely between the bodies in one or each direction lengthwise of the cable, it is possible to effect a longitudinally extending cut of limited length in the web of the 8-shaped cable.

Preferably, with a view to reducing risk of any injury being caused to a user of the hand tool, the cutter is retractable and is constrained to move relative to and between the passages defined by the two bodies in a direction extending through the plane containing the longitudinal axes of the passages between a position of the cutter at which its cutting edge does not protrude through said plane and a position of the cutter at which its cutting edge protrudes through said plane.

The retractable cutter preferably is in the form of an elongate member which carries its cutting edge at one end and which is constrained to slide within a bore extending through the bodies between the passages and through the plane containing the longitudinal axes of the passages, preferably with its axis lying substantially normal to said plane.

One of the two bodies of the tool partially defining the two passages preferably constitutes an integral part of, or is directly or indirectly detachably secured to, one end of an elongate handle and, in this case, preferably, also, the retractable cutter is an integral part of or is detachably secured to one end of a control rod sliding within a bore which extends lengthwise within the elongate handle and which is an extension of the bore in the two bodies.In one embodiment, the control rod is in screw threaded engagement with the handle and is so secured to the cutter that the control rod is freely rotatable with respect to the cutter, the arrangement being such that, by appropriate rotation of the control rod with respect to the handle, the cutter with the cutting blade at its free end can be caused to move towards or away from the plane containing the longitudinal axes of the passages.

In an alternative embodiment, the control rod is keyed to the well of the bore in the handle and is urged in a direction towards the plane containing the longitudinal axes of the passages by at least one spring, the control rod being movable in a direction away from said plane against the action of the spring or springs by an operator.

Any other convenient means may be employed for urging the two bodies of the tool together to grip loosely limited lengths of the lobes of an 8-shaped cable in the passages. In one preferred alternative arrangement, that one of the two bodies which is not integral with, or directly or indirectly detachably secured to, the handle is carried by a support arm which is constrained to slide in a lengthwise direction with respect to the handle and which can be locked with respect to the handle when the lobes of an 8-shaped aerial cable are gripped loosely in the passages; the support arm may be spring-loaded to accommodate for lengthwise movement of the tool with respect to an 8-shaped aerial cable when so loosely gripped.

Each passage defined by the opposed co-operating surfaces of the two bodies may be of approximately circular cross-section but preferably, with a view to accommodating lobes of 8-shaped aerial cables of diameters lying within a limited range of diameters differing from one another, each passage has a transverse cross-section of an elongate shape with end walls of approximately semi-circular shape.

The invention is further illustrated by a description, by way of example, of a preferred hand tool for effecting local separation of the lobes of an aerial cable of 8-shaped transverse cross-section, with reference to the accompanying drawing, in which: Figure 1 is a perspective view of the preferred hand tool; Figure 2 is a sectional side view of one of the two separately formed bodies forming the cable lobe-receiving passages of the preferred hand tool, and Figure 3 is a side view of the handle of the preferred hand tool.

Referring to the drawing, the preferred hand tool comprises a handle 1 of approximately rectangular transverse cross-section having an arm 2 secured to one side face of and protruding beyond an end face 3 of the handle. The handle 1 has a blind bore 4 of circular cross-section which opens into the end face 3 and in which is partially slidably mounted a control rod 5.

The control rod 5 is restrained against rotation with respect to the handle 1 by studs 6 which protrude radially inwardly into the bore 4 and engage in diametrically opposed slots 7 in the outer surface of the control rod.

Two separately formed bodies 11 and 12 having opposed co-operating surfaces for defining two parallel transversely spaced cable lobe-receiving passages are carried by the tool, the body 11 being secured to the free end of the arm 2 and the body 12 being in screw threaded engagement with and locked by a grub screw (not shown) in the neighbouring end of the control rod 5.

The co-operating surface of each of the bodies 11 and 12 has two parallel transversely spaced grooves 14 which, when the two bodies are urged the one towards the other as will be hereinafter explained, define two parallel passages each having a transverse cross-section of an elongate shape with end walls of approximately semi-circular shape.

A cutter 16 is secured in the body 12 so that the head 17 of the cutter is disposed between the passages that will be formed by the grooves 14 in the opposed co-operating surfaces of the bodies 11 and 12, the head of the cutter having a cutting edge which, over an intermediate part of its length, extends parallel to the longitudinal axes of the passages and which, over end parts of its length, extends in a direction normal to the plane containing the longitudinal axes of the passages.

The body 12 carried by the control rod 5 is urged towards and in contact with the body 11 secured to the free end of the arm 2 by a coil spring 18 disposed in the blind bore 4 of the handle 1. Protruding from diametrically opposite sides of the control rod 5 is a pair of finger pins 19.

When the preferred hand tool is to be used to separate locally two lolls of an aerial cable of 8-shaped transverse cross-section, the body 12 is moved, by means of the finger pins 19, against the action of the coil spring 18 away from the body 11, a part of the length of the cable at which the two lobes are to be locally separated is positioned in the grooves 14 in the surface of the body 12 and the control rod 5 is released to permit the coil spring 18 to urge the body 12 towards the body 11 so that the two lobes of the aerial cable are gripped loosely in the two parallel transversely spaced passages defined by the grooves 14 in the opposed co-operating surfaces of the bodies and so that the intermediate part of the cutting edge of the head 17 of the cutter 16 has effected a local cut in the web extending between the loosely gripped limited lengths of the two lobes of the aerial cable. Limited relative movement between the hand tool and the aerial cable in a direction parallel to the longitudinal axes of the passages is then effected in one or both directions so that one or each end part of the cutting edge of the head 17 of the cutter 16 cuts a slit of limited length in the web extending between the two lobes of the aerial cable so that the two lobes are locally separated. The control rod 5 is then moved in a direction away from the body 11 against the action of the coil spring 18 to disengage the head 17 of the cutter 16 from the cable to permit withdrawal of the aerial cable.

During use of the preferred hand tool, there is negligible risk of any damage being caused to the lobes of an aerial cable of 8-shaped transverse-section or of any injury being caused to the user of the tool.

Claims (13)

CLAIMS:

1. A hand tool for separating locally two lobes of an aerial cable of 8-shaped transverse cross-section, which hand tool comprises two separately formed bodies having opposed co-operating surfaces defining two substantially parallel transversely spaced passages each of such a cross-sectional shape and size that a limited length of one of the two lobes of an aerial cable of 8-shaped transverse cross-section can be disposed therein; means for urging the two bodies together to grip loosely limited lengths of the lobes of an 8-shaped cable in the passages; and, for cutting through the web of insulating material integral with and extending between limited lengths of the two lobes of an 8-shaped cable disposed in the passages, a cutter which is disposed between the passages and which has a cutting edge constrained to extend lengthwise with respect to the passages and protruding beyond the plane containing the longitudinal axes of the passages.

2. A hand tool as claimed in Claim 1, wherein the cutting edge of the cutter over at least one end part of its length extends in a direction substantially normal or at an acute angle to the plane containing the longitudinal axes of the passages.

3. A hand tool as claimed in Claim 1 or 2, wherein the cutter is retractable and is constrained to move relative to and between the passages defined by the two bodies in a direction extending through the plane containing the longitudinal axes of the passages between a position of the cutter at which its cutting edge does not protrude through said plane and a position of the cutter at which its cutting edge protrudes through said plane.

4. A hand tool as claimed in Claim 3, wherein the retractable cutter is in the form of an elongate member which carries its cutting edge at one end and which is constrained to slide within a bore extending through the bodies between the passages and through the plane containing the longitudinal axes of the passages.

5. A hand tool as claimed in Claim 4, wherein the axis of the elongate member lies substantially normal to the plane containing the longitudinal axes of the passages.

6. A hand tool as claimed in Claim 4 or 5, wherein one of the two bodies of the tool partially defining the two passages constitutes an integral part of, or is directly or indirectly detachably secured to, one end of an elongate handle.

7. A hand tool as claimed in Claim 6, wherein the retractable cutter is an integral part of, or is detachably secured to one end of, a control rod sliding within a bore which extends lengthwise within the elongate handle and which is an extension of the bore in the two bodies.

8. A hand tool as claimed in Claim 7, wherein the control rod is in screw threaded engagement with the handle and is so secured to the cutter that the control rod is freely rotatable with respect to the cutter, the arrangement being such, that by appropriate rotation of the control rod with respect to the handle, the cutter with the cutting blade at its free end can be caused to move towards or away from the plane containing the longitudinal axes of the passages.

9. A hand tool as claimed in Claim 7, wherein the control rod is keyed to the wall of the bore in the handle and is urged in a direction towards the plane containing the longitudinal axes of the passages by at least one spring, the control rod being movable in a direction away from said plane against the action of the spring or springs by an operator.

10. A hand tool as claimed in Claim 6, wherein that one of the two bodies which is not integral with, or directly or indirectly detachably secured to, the handle is carried by a support arm which is constrained to slide in a lengthwise direction with respect to the handle and which can be locked with respect to the handle when the lobes of an 8-shaped aerial cable are gripped loosely in the passages.

11. A hand tool as claimed in Claim 10, wherein the support arm is spring loaded to accommodate for lengthwise movement of the tool with respect to an 8-shaped aerial cable when so loosely gripped.

12. A hand tool as claimed in any one of the preceding Claims, wherein each passage has a transverse cross-section of an elongate shape with end walls of approximately semi-circular shape.

13. A hand tool substantially as hereinbefore described with reference to and as shown in the accompanying drawing.