GB2459146A

GB2459146A - Cable retention bracket

Info

Publication number: GB2459146A
Application number: GB0806508A
Authority: GB
Inventors: Peter Elliott Moore; Jamie Dobbins
Original assignee: Calder Ltd
Current assignee: Calder Ltd
Priority date: 2008-04-10
Filing date: 2008-04-10
Publication date: 2009-10-21
Also published as: GB0806508D0; WO2009125167A1

Abstract

A cable retention bracket having a cable guide 4 and attachment means 8 for securing the bracket to a cable gland 20 or electrical apparatus 40. The attachment means and cable guide are maintained at an appropriate distance apart by a spacer element 6. The cable guide may be an adjustable clamp 12 and the interior of the guide may be provided with a cable surrounding sleeve 14. The attachment means 8 may be a flange with a bore which may be provided with an ingress protection washer and the spacer element 6 may comprise a pair of arms that converge towards the cable guide. The bracket may be incorporated into a cable gland assembly.

Description

CABLE RETENTION BRACKET

The present invention relates to an improved cable retention bracket.

The installation of cabling into some items of equipment requires the use of a cable gland assembly, such as a HawkeTM universal gland or similar, to prevent the cable chaffing on the edge of the equipment and to provide a means of retention. The cable is threaded though the gland assembly and the wires at the end of the cable are attached to the appropriate connectors contained within the electrical housing, the gland assembly being attached to the housing by means of, for example, a threaded mechanism. The gland within the assembly prevents the ingress of water and other contaminants into the interior to the equipment and, in some cases, provides an explosion proof barrier. In some circumstances, it is necessary for the cable to be physically supported remote from the connection such that strain cannot be applied to the gland should a force be applied to the cable. Typically, this retention is provided by the installation of a remote bracket or hook to which the cable is secured.

However, the adequate installation of remote brackets and hooks is a time-consuming and costly process.

An object of the present invention is to provide an improved cable retention bracket that aims to overcome, or at least alleviate, the abovementioned drawbacks.

Accordingly, a first aspect of the present invention provides a cable retention bracket comprising a cable guide and attachment means separated by a spacer element.

I

The cable guide is preferably in the form of an adjustable clamp for receiving the cable. Preferably, the clamp comprises two substantially symmetrical parts for defining a passage therebetween for receiving the cable, in particular each being semicircular in profile, that are held together by suitable fastening means, such as a threaded screw, nut and washer. Alternatively, the cable guide may be substantially circular with a gap extending radially therethrough which may enable loosening and tightening of the clamp around the cable. It is preferable to provide an elastomeric sleeve, such as an 0-ring or, more preferably, a laminated or non-laminated foam ring, within the interior of the guide.

Preferably, the attachment means is in the form of a flange that is spaced apart from the cable guide but extends substantially parallel thereto, being separated therefrom by the spacer element. Preferably, the flange is provided with a bore therethrough, the bore being dimensioned to receive a part of a cable gland assembly, such as a threaded portion thereof. In this manner, the bracket may be secured to an electrical apparatus by the fastening of the gland to the apparatus in the conventional way.

Optionally, an ingress protection washer (IP washer) may be provided within the bore of the flange where conditions require such additional protection.

The spacer element may be any suitable member that maintains an appropriate distance between the attachment means and the cable guide. In a preferred embodiment of the present invention, the spacer element comprises at least one arm extending from the cable guide to the attachment means. Preferably, the spacer element comprises a pair of arms that converge towards the cable guide. More preferably still, the arms extend parallel from each side of the attachment means, such as the flange, substantially perpendicularly thereto and then converge to meet at an apex at the base of the cable guide.

It is to be appreciated that the spacer element may be formed such as to provide a cable guide in the same plane as the bore of the attachment means or the spacer element may be constructed such as to provide a change of plane, thereby accommodating different types of cable gland assemblies.

Preferably, the cable guide, spacer element and attachment means are formed integrally from a single piece of material, for example being injection moulded or machined from a piece of flat metal. The thickness and type of material used for the bracket, in particular, the spacer element, will depend upon the weight of the cable to be supported by the bracket.

It is to be appreciated that the cable retention bracket of the invention is preferably provided as a separate entity for attachment to an existing cable gland assembly. However, the bracket also may be formed as part of the cable gland assembly. To this end, a second aspect of the present invention provides a cable gland assembly that includes a cable retention bracket according to the first aspect of the present invention. The cable gland assembly may include standard components in the art, for example, one or more of the following; a threaded hub element, at least one compression nut, "0" ring seal, gasket seal and an armour braid clamping element.

For a better understanding of the present invention and to show more clearly how it may be carried into effect reference will now be made by way of example only to the accompanying drawings in which: Figure 1 is a perspective side view of a cable retention bracket according to one embodiment of the present invention; Figure 2 is a perspective top view of the cable retention bracket shown in Figure 1; Figure 3 is a perspective view of the cable retention bracket of Figures 1 and 2 shown attached to a cable gland assembly; Figures 4 and 5 are respectively perspective side and bottom views of the cable retention bracket of Figures 1 and 2 shown secured to an electrical apparatus by means of the cable gland assembly; and Figures 6a to 6d are schematic diagrams of the cable retention bracket incorporating an IP washer.

Referring to Figures 1 and 2 of the accompanying drawings, a cable retention bracket 2 according to one embodiment of the present invention is illustrated. The bracket comprises a cable guide 4, a spacer element 6 and attachment means 8, the various parts being machined from flat metal. The cable guide 4 comprises a pair of symmetrical members 4a, 4b that define a substantially circular bore 10 between the internal faces of the members for receiving a cable. Suitable fastening means 12, such as a screw, nut and washer arrangement, is provided between the two members for securing them together. A laminated foam ring 14, such as that supplied under the trade name ROXTECH is placed within the bore 10.

The spacer element 6 extends from the base of the cable guide 4 to the attachment means 8. The spacer element comprises a pair of arms 6a, 6b that diverge from the cable guide. At the point where the distance between the arms is substantially the same as the width of the attachment means 8, the arms extend parallel to each other to the attachment means. The attachment means comprises a flange extending perpendicularly from the end of the arms 6a, 6b. A cylindrical bore 16 is provided through the flange. The positioning of the bore 16 is such that it lies substantially in the same plane as the bore 10 provided through the cable guide.

Figures 3 to 5 illustrate the installation of a cable 60 within the cable retention bracket 2 via a cable gland assembly 20. The bore 16 of the attachment means 8 is placed over a threaded end 22 of a cable gland assembly 20 such that the flange contacts a face of the connector (see Figure 3). A cable 60 is then threaded through the cable guide 4 of the bracket and the cable gland assembly 20, which is then attached to an electrical apparatus 40 by means of the screw fixing 22. The flange 8 of the cable retention bracket is sandwiched between an external face of the cable gland and the electrical housing to secure the bracket in place. The cable guide may be tightened around the cable by adjusting the fastening means 12, as required.

Furthermore, the laminated foam ring can also be adjusted to the required thickness by the removal of an appropriate number of layers of the ring to accommodate a particular diameter cable within the bracket.

In this manner, a cable 60 that is connected to a piece of electrical apparatus by means of a cable gland assembly 20 can be easily retained at a specified distance from the gland exit by the cable retention bracket 2 according to the present invention.

The incorporation of the bracket adds minimal time to the assembly procedure and considerably reduces the onward cost of designing and fitting remote brackets and/or hooks.

The invention also eliminates the requirement for the use of an additional conventional earthing plate, typically used with such gland types, as the earth conductor may be fixed directly to the invention itself, should this be required.

An ingress protection washer 70 may be provided within the bore of the attachment means, as illustrated in Figures 6a to 6d of the accompanying drawings.

In the assembled unit, the washer fits within the bracket/gland interface to provide a watertight seal.

Whilst the cable retention bracket illustrated in the accompanying drawings has a cable guide in the same plane as the bore of the attachment means, the invention is not limited to this arrangement. For example, the cable gland assembly may include a bend, preferably provided within the spacer element, such that the cable enters the assembly in a different plane to its passage into the electrical apparatus.

The attachment means may also differ to that shown, for example, comprising a clamping mechanism for securing the bracket to the gland assembly or the electrical housing. However, this will increase the actions required for installation of the cable within the apparatus and therefore the illustrated arrangement is preferred.

The cable retention bracket according to the present invention may be provided as an integral part of a cable gland and connector fixing or fitted retrospectively.

Claims

CLAIMS1. A cable retention bracket comprising a cable guide and attachment means separated by a spacer element.
2. A cable retention bracket as claimed in claim 1 wherein the cable guide is an adjustable clamp for receiving the cable.
3. A cable retention bracket as claimed in claim 1 or claim 2 wherein a sleeve is provided in the interior of the guide for surrounding the cable.
4. A cable retention bracket as claimed in any one of claims 1 to 3 wherein the attachment means comprises a flange spaced apart from the cable guide and extending substantially parallel thereto, the flange having a bore therethrough and being separated from the cable guide by the spacer element.
5. A cable retention bracket as claimed in any one of claims 1 to 4 wherein the spacer element maintains an appropriate distance between the attachment means and the cable guide.
6. A cable retention bracket as claimed in claim 5 wherein the spacer element comprises at least one arm extending from the cable guide to the attachment means.
7. A cable retention bracket as claimed in claim 6 wherein the spacer element comprises a pair of arms that converge towards the cable guide.
8. A cable retention bracket as claimed in claim 7 wherein the arms extend parallel from each side of the attachment means and substantially perpendicularly thereto and converge to meet at an apex at the base of the cable guide.
9. A cable retention bracket substantially as hereinbefore described and with reference to Figures 1 and 2 or 6a to 6c of the accompanying drawings.
10. A cable gland assembly incorporating a cable retention bracket according to any one of claims 1 to 8.
11. A cable gland assembly substantially as hereinbefore described and with reference to Figures 3 to 5 or 6d of the accompanying drawings.