WO1999003182A1

WO1999003182A1 - Bung assembly

Info

Publication number: WO1999003182A1
Application number: PCT/GB1998/002031
Authority: WO
Inventors: Nigel Haire
Original assignee: Austin Taylor Communications Limited
Priority date: 1997-07-11
Filing date: 1998-07-10
Publication date: 1999-01-21
Also published as: GB9714589D0; AU8347598A

Abstract

A bung assembly for sealing an aperture (14) into which a cable (16) is inserted. The assembly includes a bung (1) for insertion into an aperture (14), the bung defining a passage (2) through which a cable (16) is inserted. A sealant material (9) is also provided, operative to form a seal between the bung (1) and an aperture (14) into which it is inserted and a cable (16) inserted into the bung (1).

Description

BUNG ASSEMBLY

The present invention relates to a cable entry bung assembly for sealing

an aperture in a wall, panel or other such divider through which one or more

cables pass.

One existing cable entry bung comprises a short, open ended, tubular

rubber member having an external flange at one end. In use the bung is

inserted into an aperture in for example a wall and the flange lies adjacent to

the surface of the wall around the aperture. A cable is passed through the

bung. The purpose of the bung is to fill the annular space between the cable

and aperture through which the cable passes in order to seal the aperture, for

example to prevent passage of water or air through the aperture.

The extent to which such a bung is able to effectively seal an aperture

depends on a number of factors. Primarily the quality of the seal obtained

depends on how closely a particular bung fills a particular aperture and how

closely a particular cable fits into the bung. It is therefore necessary that the

size of bung used is carefully chosen for any particular application. Even so,

any inconsistency in the cable diameter or dimensions of the aperture to be

sealed can lead to a poor seal being formed.

Another factor influencing the extent to which a bung can form an effective seal is the extent to which the surfaces of the bung material can form

a seal with the aperture or cable. Where a bung is used to seal an aperture

made' through a masonry wall, for example, the rough nature of the surface

surrounding the aperture will not seaiingly engage with the smooth surface of

the flange surrounding the bung, consequently the seal obtained is poor and

water may enter the aperture.

It is an object of the present invention to provide an improved cable entry

bung which addresses the problems associated with existing bungs and allows

reliable seals to be formed in apertures formed in a variety of materials whilst

also accommodating a range of cable to sizes.

According to a first aspect of the present invention there is provided a

bung assembly comprising a bung, for insertion into an aperture, which defines

a passage into which a cable may be inserted wherein there is also provided a

sealant material, operative to form a seal between the bung and an aperture

into which the bung is inserted and/or the bung and a cable inserted into the

bung.

According to a second aspect of the present invention there is provided

a method of sealing an aperture into which a cable is inserted comprising the

steps of providing a bung, for insertion into an aperture, which defines a

passage into which a cable may be inserted, inserting a cable into said bung, inserting said bung into an aperture and providing a sealant material in such a

manner that when the bung is inserted into an aperture the sealant material

forms a seal between the bung and the aperture and/or the bung and cable.

The sealant material preferably comprises a self heal gel, more preferably

a self heal waterproofing gel. The sealant material preferably forms a seal

between the bung, aperture and cable.

The bung may be substantially annular in cross-section , this is preferable

where it is desirable to seal a substantially circular aperture into which there is

inserted a cable of substantially circular cross-section. The bung may however

have any suitable cross-section in order to accommodate a particular type of

cable and to fit into any particular shape of aperture.

Around an outside surface of the bung there is preferably provided a

projecting shoulder, forming a flange. This flange is preferably arranged to lie

adjacent to the surface into which an aperture extends when the bung is

inserted into said aperture. Where the bung is annular in cross-section the

flange is preferably formed by a radially projecting shoulder.

When the bung is inserted into an aperture the sealant material is

preferably disposed at least between the flange and the surface into which the aperture extends.

Teeth may be disposed on the surface, of the bung to enable the bung

to grip the inside of an aperture into which it is inserted. Where the bung is

annular in cross-section it is preferred to form a series of radial projections in

a sawtooth form around the part of the bung which is intended to be inserted

into an aperture. The sawtooth arrangement is preferably so arranged as to

facilitate insertion of the bung into but to restrict removal of the bung from an

aperture.

Resilient projections may be provided which extend into the passage

defined by the bung. Where the bung is of annular cross-section the resilient

projections preferably serve to reduce the diameter of the passage through the

bung. The resilient projections are preferably arranged to be deflected by a

cable when inserted into the passage and so form a seal around the cable.

Where a cable is inserted into the passage defined by the bung the

sealant material is preferably disposed in the passage in any space between the

cable and the bung, forming a seal between the cable and bung.

Preferably, one or more apertures are provided between the passage

defined by the bung and the outside surface of the bung. Where the bung has

a flange the apertures are preferably formed adjacent to the flange. Where the bung is of annular cross-section there may be provided at least one aperture

and preferably more than one aperture extending radially through and

circumferentially spaced about the bung. Said apertures preferably connect

points on the outer surface of the bung, adjacent to the flange, with the

passage defined by the bung.

The apertures are preferably arranged to allow flow of sealant material

therethrough. As such it will be appreciated that the apertures are arranged

to connect the two preferred locations for the sealant material when the bung

is installed into an aperture and a cable is inserted into the bung. That is, the

space between the flange and the surface in which the aperture is formed and

the space between the cable and the internal surface of the bung defining a

passage therethrough.

The bung may be formed from a polymer material by injection moulding,

although any other suitable material or manufacturing process may be used.

The material from which the bung is formed is preferably UV light stable, heat

stabilised, non isotropic, flame retardant and durable.

The bung may be formed from a resilient material.

The sealant material may be provided on an additional component which

may be formed from the same material as the bung. The sealant may be disposed on opposite sides respectively of this component which may be

placed between a portion of the bung, particularly the flange, and the surface

surrounding an aperture into which . the bung is inserted.

The sealant material is preferably fluid.

Where the bung is of annular cross-section the sealant material is

preferably disposed on a washer. The sealing material may be moulded onto

opposite faces respectively of said washer.

The washer is preferably arranged in order that the bung may be inserted

into the washer, to the extent that the flange will not pass though the washer.

Preferably the washer is of similar dimensions to the flange.

In use the bung is preferably inserted into the washer and then into an

aperture. When so inserted the sealant material, disposed on opposite faces

of the washer preferably forms a seal between the flange, washer and surface

surrounding the aperture into which the bung is inserted. Where apertures are

provided in the bung as hereinbefore described then some sealant material

preferably flows through the apertures and into the passage defined by the

bung and forms a seal between the inside surface of the bung and any cable

extending through the bung. The additional component on which the sealant material is provided may

be so shaped as to influence the way in which the sealant material flows.

Preferably the component is shaped to direct at least .some of the sealant

material through any apertures formed in the bung.

Where the additional component is a washer the washer is preferably

thicker at its outside diameter than at its inside diameter, the sides of the

washer being tapered. Additionally there is also provided a shoulder which

extends in an axial direction from the surface of a side of the washer, at its

outermost diameter. Said shoulder is preferably arranged to lie adjacent to the

outside of the shoulder which projects from the bung to form the flange. The

purpose of the shoulder is to prevent any sealant material flowing radially

outwards from the space between the flange and washer, thereby maximising

the amount of sealant material between the washer and surface surrounding

the aperture into which the bung is inserted and between any cable inserted

into the bung and the inside surfaces of the bung defining a passage

therethrough.

The sealant material may have adhesive properties, the sealant material

may be so disposed on the additional component so as to retain the component

on the bung before insertion.

The bung assembly enables superior seals to be achieved than with prior art bungs. The provision of a sealant material enables effective, waterproof,

seals to be formed with a variety of surfaces and cables. As such the overall

dimensions of the bung are not as critical as with prior art bungs. Where the,

sealing material is also directed to the passage through which a cable is

inserted this enables a single size of bung to accommodate cables of differing

dimensions and cross-section whilst still providing an effective seal. Where

resilient projections and particularly a wiper blade is provided in the passage

this further improves the seal formed around the cable. Bung assemblies of the

present invention can accommodate widely varying cable diameters, for

instance a single size of bung assembly may accommodate cable diameters in

the range 4 to 10mm. The described bung assembly is particularly suited for

the installation of cables through the walls of buildings.

This method of sealing an aperture described above enables an effective

waterproof seal to be readily formed between the cable and bung, and bung

and aperture by the sealant material. By inserting the cable first the sealant

material is able to flow around the space between the cable and the surfaces

of the bung defining a passage therethrough where the sealant flows through

apertures formed in the bung. If the bung were inserted into the aperture first

any sealant material in the passage through the bung may be ejected by the

insertion of the cable and a satisfactory seal between bung and cable may not

be obtained. In order that the invention be more clearly understood there is now

described an embodiment thereof, by way of example, with reference to the

.accompanying drawings in which:-

Fig.1 shows a longitudinal cross-section through a similar bung

assembly;

Fig.2 shows a similar longitudinal cross-section through a similar bung

assembly to that illustrated in Fig.1 , inserted into an aperture and into which

there extends a portion of cable.

Referring to Figure 1 , there is illustrated a bung 1 . The bung 1 is in the

form of a hollow open ended cylinder. The cylinder defines a passage 2 into

which a cable may be inserted. At one end of the bung there is an outer

radially projecting shoulder which forms a flange 3. On the remaining outer

surface of the bung are a series of smaller profiled radial projections 4 which

form a sawtooth shape. Projecting radially into the passage defined by the

bung at the end of the bung with the flange 3 there is a wiper blade 5. Four

circumferentially spaced apertures 6 extend through the bung between the

passage 2 and points on the outer surface of the bung adjacent to the flange

3. The bung is formed from a polymer material by injection moulding. The

wiper blade 5 is resilient. Disposed around and moveable relative to the bung 1 is an annular

washer assembly 7. The washer assembly comprises a washer 8 and a self

heal waterproofing gel 9.

The cross-section of the washer is tapered such that the thickness of the

washer increases with its radius. The side of the washer which faces the

flange 3 is more tapered than the opposite side. A shoulder 10 projects axially

from the surface of the washer at its outer radius. The shoulder 10 projects

towards the flange 3. The washer 8 is formed from a polymer material by

injection moulding. The self healing waterproofing gel 9 is disposed on

opposite sides respectively of the washer 8. The self healing waterproofing gel

9 is moulded with the washer 8.

The illustrated bung assembly is designed to seal, sufficient to exclude

water, an aperture into which a cable passes. For example a hole drilled

through the wall of a building to admit a telecommunications cable.

In use a cable is inserted through the passage 2 defined by the bung

assembly, either before or after said cable is passed into an aperture which

extends into a wall or similar. The bung assembly is then moved along the

cable or with the cable into the aperture into which the cable passes where the

projections 4 engage with the aperture. The bung assembly is pushed into the

aperture so as to bring the flange 3 close to the surface of the wall or similar which surrounds the aperture. The effect is to bring the washer assembly 7

into contact with the wall or surface and so to move the washer assembly 7

towards the flange 3 and ultimately to compress the washer assembly 7.

The self healing waterproofing gel 9 is fluid and therefore when

compressed will flow. When the washer assembly 7 is compressed between

flange 3 and another surface the self healing waterproofing gel will flow in a

radial direction, the shape of the washer 8 is arranged to encourage the gel 9

to flow to smaller radii and particularly to flow through aperture 6, and into the

passage 2 to form a seal between the cable and bung. The gel 9 will also flow

radially outwards from a seal between the bung 1 , flange 3, washer 7 and

surrounding the aperture into which the bung assembly is inserted. The

shoulder 10, serves to prevent the self heal waterproofing gel 9 from egressing

onto the exposed parts of the bung 1 upon installation.

Referring to Fig.2 there is illustrated a bung assembly installed as

described above. The illustration shows a bung 1 2, and washer 13 similar to

those illustrated in Fig.1 . The bung 1 2 is inserted into an aperture 1 4 which

is formed in a surface 1 5. A portion of a cable 16 is disposed in the passage

defined by the bung 1 2.

The sawtooth projections 17, on the surface of the bung 1 2 lie adjacent

to the inside surfaces of aperture 1 4. The sawtooth projections 17 are operative to engage with inside surfaces of the aperture 1 4. The sawtooth

projections 17 are arranged so as to prevent movement of the bung 12 out of

the aperture 14.

The wiper blade 20 is deflected by the cable 16 and forms a seal with

the surface of the cable. The provision of the wiper blade 20 enables the use

of different diameters of cable with a bung assembly of a given size. The wiper

blade 20 provides additional protection against water and other substances

passing through the aperture once a cable 1 6 has been introduced into the

bung assembly.

A self healing waterproofing gel 18 is disposed and forms a seal between

the surface 1 5, washer 1 3, flange 19, cable 1 6 and the inside surface of the

aperture 14. The self healing waterproof gel 18 enables an effective barrier to

be formed easily and reliably whilst accommodating changes in the outside

diameter of the cable 1 8 and the inside diameter of the aperture 14.

The illustrated bung assembly represents an improvement over existing

cable entry bungs. The self heal waterproofing gel enables a waterproof seal

to be easily and reliably formed. One size of bung assembly is able to

effectively seal a range of aperture sizes and to accommodate a range of cable

sizes. It is to be understood that the above embodiment is described by way

of example only and that many variations are possible without departing from

the invention.

Claims

1 . A bung assembly comprising a bung, for insertion into an aperture, which

defines a passage into which a cable may be inserted wherein there is also

provided a sealant material, operative to form a seal between the bung and an

aperture into which the bung is inserted and/or the bung and a cable inserted

into the bung.

2. A bung assembly as claimed in claim 1 , wherein the sealant material is

a self heal gel.

3. A bung assembly as claimed in either claim 1 or claim 2, wherein the

sealant material is operative to form a seal between the bung and an aperture

into which the bung is inserted and the bung and a cable inserted into the

bung.

4. A bung assembly as claimed in any preceding claim, wherein a resilient

projection extends into the passage defined by the bung.

5. A bung assembly as claimed in any preceding claim, wherein projections

are disposed on the surface of the bung, arranged so as to facilitate insertion

of the bung into but restrict the removal of the bung from an aperture.

6. A bung assembly as claimed in any preceding claim, wherein there is provided a flange around an outside surface of the bung, arranged to lie

adjacent to the surface into which an aperture extends when the bung is

inserted into said aperture and the sealant material is operative to form a seal

between the flange and said surface.

7. A bung assembly as claimed in any preceding claim, wherein an aperture

is provided between the passage defined by the bung and the outside surface

of the bung.

8. A bung assembly as claimed in claim 7, when appendant to claim 6,

wherein the aperture is formed adjacent to the flange.

9. A bung assembly as claimed in any preceding claim, wherein the sealant

material is provided on a separate component.

10. A bung assembly as claimed in claim 9, wherein the separate component

is a washer into which the bung may be inserted and the sealant material is

moulded onto opposite faces respectively of the washer.

1 1 . A bung assembly as claimed in claim 10, wherein the faces of the

washer are radially inwardly tapered.

1 2. A bung assembly as claimed in either claim 10 or 1 1 , wherein the washer includes an axially extending shoulder.

1 3. A method of sealing an aperture into which a cable is inserted comprising

the steps of providing a bung, for insertion into an aperture, which defines a

passage into which a cable may be inserted, inserting a cable into said bung,

inserting said bung into an aperture and providing a sealant material in such a

manner that when the bung is inserted into an aperture the sealant material

forms a seal between the bung and the aperture and/or the bung and cable.

1 4. A method of sealing an aperture into which a cable is inserted as claimed

in claim 13, wherein the sealant material is a self heal gel.

1 5. A method of sealing an aperture into which a cable is inserted as

claimed in either claim 13 or 14, wherein the sealant material is provided in

such a manner that when the bung is inserted into an aperture the sealant

material forms a seal between the bung and the aperture and the bung and the

cable.

1 6. A method of sealing an aperture into which a cable is inserted according

to any of claims 1 3 to 16 further comprising the step of providing the sealant

material on a separate component.

1 7. A method of sealing an aperture as claimed in any of claims 13 to 16, wherein an aperture is provided between the passage defined by the bung and

the outside surface of the bung and further comprising the step of forcing some

sealant material through the aperture so as to form a seal between the bung

and cable.