GB2356742A

GB2356742A - Cable gland with cable grip and sealant

Info

Publication number: GB2356742A
Application number: GB9927654A
Authority: GB
Inventors: David Curry
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-11-24
Filing date: 1999-11-24
Publication date: 2001-05-30
Anticipated expiration: 2019-11-24
Also published as: GB2356742B; GB9927654D0

Description

2356742 GRIP GLAND FOR ELECTRICAL CABLES This invention relates to glands

for the entry or exit of electrical cables to or from enclosures.

It is common practise to provide such glands to effect a twofold function. Firstly, to provide a seal against the ingress of fluids, water and other contaminants and, secondly, to provide a grip for the cable to prevent external strain from being applied to the connections within the enclosure to which the gland is applied. Generally, in existing glands, these functions are provided by a screwed ferrule bearing down on a rubber type insert such that the insert is compressed onto the cable, thus providing a seal and a simultaneous grip.

The difficulty with such glands as existing is that each size and shape of cable in use has to have a corresponding insert to match in order to perform the designed functions correctly. Furthermore the grip function is adversely affected by moisture on the cable. It is also unlikely that the gland can be re-used without replacing the insert, which will have become distorted after long periods of compression on to the cable. This can be a major disadvantage in carrying out repairs and maintenance.

The object of the present invention is to provide a gland that will seal positively against the ingress of fluids and other contaminants regardless of the size and shape of the cable, provide a positive cable grip under all conditions and be reusable to any other size and shape of cable. This is achieved by forming the gland in two halves that can be locked together, each half being filled with a specialised sealant in the form of a gel, that has the unique property of returning to it's original condition when released after Compression. Said sealant is not itself the subject of this invention and there are a number of proprietary types available that will perform the required function. One half of the gland embodies a universal cable grip that will restrain the cable from movement in addition to any grip provided by pressure of the sealant. A prototype of the gland has satisfactorily passed al I the tests required for approval in hazardous areas, specifically to the universally accepted standard IP 68.

A specific embodiment of the invention will now be described, by way of an example only, by reference to the accompanying drawing.

Fig I depicts the two halves of the gland before assembly. The gland is divided symmetrically along the centreline such that when closed together the threaded portion I of each half forms a true cylindrical thread conforming to the required standard in use. The upper half 2 has two prongs 3 with a claw 4 at the extremity. The lower half 5 has cavities 6 in which the prongs 3 engage. The claw 4 and cavity 6 are designed such that the prongs 3 snap into position and hold the two halves 2 and 5 positively and tightly together. The lower half 5 has embodied within it two members 7 that form a cable grip, preventing any Strain on the cable being transferred to any internal connections in the enclosure to which the gland is to be fitted. Both upper half 2 and lower half 5 have a thumb and finger grip area 8 to facilitate closure. Both the said halves are filled with a proprietary sealant 9 in the form of a gel having the property of restoration after compression.

2- Fig 2 depicts the gland after assembly around a cable. To release the two halves for reuse, slots 10 are provided in the lower half 5 through which the claws 4 can be released by pressing with a suitable instrument such as a small screwdriver.

Each half 2 and 5 of the gland has apertures I I that are large enough to accommodate the largest size cable to be used, consistent with the overall size of the gland concerned. Within such constraint any size or shape of cable can be accommodated, the sealant 9 being compressed accordingly by the action of pressing the two halves of the gland together. As previously described, on release the sealant will, by the nature of it's properties, return to it's original state, ready for reuse.

It will be appreciated that in normal use as an entry or exit to an enclosure, the gland, after assembly, is inserted through an appropriate aperture in the enclosure and secured with a back nut in the conventional manner.

Claims

I A cable gland for entry and exit to or from an enclosure providing a positive sea] against the ingress of fluids and contaminants and with a positive cable grip embodied within the gland.
2. A cable gland according to Claim I that will accommodate a range of cable sizes and shapes without modification or change of internal components.
3. A cable gland according to claim 2 that is reusable without modification or change of internal components.
4. A cable gland according to claim 3 that consists of two halves with means for engagement that can be released in order to separate the two halves for reuse.
5. A cable gland according to claim 4 embodying a cable grip in the form of members disposed such that strain on the cable causes a tightening of the grip.
6. A cable gland according to claim 5 designed to use any one of a number of proprietary sealants having the required properties of restoration after compression.
7. A cable gland substantially as described herein with reference to the accompanying drawing Figs I and 2.

7. A cable gland substantially as described herein with reference to the accompanying drawing Figs I and 2.

Amendments to the claims have been filed as follows 41- CLAIMS 1. A cable gland for entry and exit to or from an enclosure, comprising a housing divided into two halves longitudinally along the axis of the cable, with means for engagement of the two halves in the closed position, said means being capable of release in order to separate the two halves of the housing for reuse.

2. A cable gland according to Claim I that provides a positive seal against the ingress of fluids and contaminants.

A cable gland according to Claim 2 embodying a positive cable grip preventing movement of the cable under strain without impairing the sealing qualities of the gland.

4. A cable gland according to Claim 3 that will accommodate a range of cable sizes and shapes without modification or change of internal components.

5. A cable gland according to claim 4 that is reusable without modification or change of internal components.

6. A cable gland according to claim 5 designed to use any one of a number of proprietary sealants having the required properties of restoration after compression.