GB2478344A

GB2478344A - Protective cover for inflatable bladders or balloons

Info

Publication number: GB2478344A
Application number: GB1003644A
Authority: GB
Inventors: Brian Morrie Back
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-03-05
Filing date: 2010-03-05
Publication date: 2011-09-07
Also published as: GB201003644D0

Abstract

A cover comprising a w oven metallic mesh with a highly elastic outer sleeve assembly and a floating inner buffer sleeve that can be fitted over items such as inflatable bladders or balloons to give them protection from rodent attack and to safely dissipate static electricity generated by mechanical friction during the inflation or deflation of the bladderiballoon so covered.

Description

Protective cover for inflatable bladders or balloons.

The present invention relates to a cover comprising a woven metallic mesh with a highly elastic outer sleeve assembly and a floating inner buffer sleeve that can be fitted over items such as inflatable bladders or balloons to give them protection from rodent attack and to safely dissipate static electricity generated by mechanical friction during the inflation or deflation of the bladder/balloon so covered.

Inflatable bladders have been used for thousands of years for a variety of applications for blocking or sealing off drains, ducts, sewers, shafts, pipes, etc. Typically, bladders and balloons used in this application are often damaged by rodents leading to failure. Also during the inflation process the movement friction of the wall fabrics against themselves, or the injection of dry gases, or movement against the wall of the drain, duct, pipe, etc can give rise to the generation of static electricity that if discharged can trigger explosions if potentially explosive dusts or gases are present.

Proof of the ability to dissipate / not generate static electricity is an essential requirement of international safety regulations such as ATEX.

This invention describes the construction of a cover assembly that can be equally applied to existing or new bladder/balloon assemblies to improve the rodent protection and also to dissipate static electricity prerequisite to ATEX compliance.

Preferably, the cover comprises of three layers: An outer elasticated sleeve; core comprising of a cylindrical tube of woven wire mesh and an inner floating loose fitting buffer sleeve.

Preferably, the outer sleeve is manufactured from a highly elastic material such as latex rubber with an expansion ratio of typically 400%.

Preferably, the mesh is manufactured from stainless steel which has high durability and a low tendency to generate sparks when the threads of the mesh pass over one another during the inflation and deflation process as the mesh expands and contracts.

Preferably, the stainless steel mesh core is woven as a tube with a diameter equal to or slightly greater than the fully inflated bladder that it is designed to protect or the drain, duct size that it is to be inserted. One end of the woven mesh cylinder is stitched closed to form a sock, whilst the other end is left open with a draw wire threaded through the holes of the mesh.

Preferably, the inner tubelsleeve would act as a floating buffer to ease the movement of the steel mesh over the bladder. This inner sleeve would have a diameter sufficient to allow for the bladders/balloons complete inflation. This sleeve would be free moving and low friction to reduce the wear on the bladder / balloon during inflation.

Preferably, the whole assembly would be fitted over the bladder/balloon with it fully deflated and squeezed out into a sausage shape. The metal mesh would be cut longer than the inner buffer permitting if necessary for it to be directly bonded to the support structure. The outer elastic sleeve would be cut even longer so that it would cover the entire assembly and any earth bonding connections in order to minimise the risk of debris build up.

Preferably, in applications where there is an atmosphere present that is potentially explosive the metallic mesh would be electrically bonded to the support structure, which itself would be bonded to ground. By doing so a Faraday Cage is created which keeps all the surfaces are equal potential and stops static build-up when the bag is inflated.

At least one embodiment of the invention will be described below, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a cross sectional drawing of the covers wall showing the three distinct layers; Figure 2 is a Plan cut away section drawing of the cover; Figure 3 illustrates the way the cover would be applied to a typical bladder / balloon deflated; Figure 4 is the way the sleeve would look when applied to a typical bladder / balloon inflated; Figure 5 illustrates the way the assembly would be earth bonded to the bladders! balloon feed pipes assembly.

Throughout the following description, identical references numerals will be used to identify parts.

Referring to Figure 1, layer 1 is the outer high elasticity rubber layer. 2 is the core wire mesh layer. 3 is the inner loose fit sleeve that acts as a buffer between the cover and the bladder/balloon.

Referring to Figure 2, the cutaway clearly shows the wire mesh 2 below the outer elastic sleeve I and finally the inner floating buffer layer 3. The whole assembly is sealed on all sides to form a series of socks except end from the direction 4.

Referring to Figure 3, when the cover is fitted over a deflated bladder/balloon its elasticity will have the tendency to compress the assembly to the shape shown, this is intentional as it reduces the profile of the bladder for ease of insertion and/or storage within the drain, pipe, etc. Referring to Figure 4, the assembly is inflated and stretched to shape by the internal pressure from the inflated balloon / bladder.

Referring to Figure 5, the complete assembly is bonded / grounded to the metallic feed pipe 7 of the bladder/balloon 5. Clip / draw wire 6 crimps the mesh to the feed tube. 8 is a tie that holds the external elastic sleeve to the feed tube and covers all the exposed mesh. 9 is the support bracket for the assembly.

Claims

Claims I. A cover comprising a woven metallic mesh with an elastic rubber outer sleeve and inner floating buffer sleeve assembly that is applied to inflatable bladders, that affords protection from rodent attack and safely dissipates static electricity generated by friction during the inflation and deflation of the bladder or balloon.
2. A cover assembly as per Claim 1 where the elasticated outer has a soft conforming surface texture that forms an efficient seal when forced against the wall of a shaft, drain, duct, pipe or sewer etc under the force of inflation of a bladder within.
3. A cover assembly as per Claim I where the elasticated outer assembly provides a smooth surface to prevent debris from clinging to the metallic mesh.
4. A cover assembly as per Claim I where the assembly is elasticated to ensure that the whole assembly is gathered up and the fluid or gas used to fill the bladder is squeezed out when deflated such that the deflated assembly then does not unduly obstruct the shaft, duct, pipe, tunnel, sewer etc.
5. A cover assembly as per Claim I where there is a floating inner buffer sleeve that acts to reduce the wear on the mesh on the surface of the bladder I balloon.
6. A cover assembly as per Claim I where it can be retro-fitted to existing inflatable bladder systems to improve protection from rodent attack.
7. A cover assembly as per Claim 1 where it can be retro-fitted to existing inflatable bladder systems to dissipate any static electricity generated improving safety in explosive gas and dust environments such as sewers.