GB2282175A

GB2282175A - Vented tank with barrier to animal ingress

Info

Publication number: GB2282175A
Application number: GB9318727A
Authority: GB
Inventors: James Robert Underwood
Original assignee: Micro Mesh Engineering Ltd
Current assignee: Micro Mesh Engineering Ltd
Priority date: 1993-09-09
Filing date: 1993-09-09
Publication date: 1995-03-29
Anticipated expiration: 2013-09-09
Also published as: GB9318727D0; GB2282175B

Abstract

A tank has a vent pipe with a removable pipe section (11) which sealingly engages the remainder of the vent pipe. A screen (19) is positioned across the lumen (14) of the pipe section (11) to present a barrier to ingress of animals through the vent pipe and into the tank. The removable pipe section (11) has a collar (15, 16) slidably mounted on the pipe section (11) at respective ends (12, 13). Each collar (15, 16) has a first O-ring (17) sealingly engaging the collar to the pipe section (11), a second O-ring (18) sealingly engaging the collar with the remainder of the vent pipe. <IMAGE>

Description

VENTED TANK WITH BARRIER TO ANIMAL INGRESS The present invention relates to a tank having a barrier to ingress of animals into the tank. The term animal is used in this specification to include small creatures such as flies as well as larger animals such as mice and small birds. The invention also relates to a device for providing such a barrier.

It is well known to provide a vent pipe in a tank, for example, a water storage tank. The vent is often provided by an overflow pipe which serves a dual purpose. Such an arrangement is widely seen on water tanks in houses as well as larger public and commercial buildings.

There is, however, a problem with such water tanks, because the humid and sheltered environment in the lumen of the vent pipe attracts insects such as flies, and larger animals such as mice and small birds, which may enter the tank by the vent pipe, so that the tank's water supply is contaminated. The release from the decaying animal of certain bacteria (e.g. the Legionella bacterium) into the water may have serious implications for water-cooled air conditioning systems.

A new Byelaw requires that domestic water storage tanks are provided with an overflow pipe and cistern which are constructed and arranged to exclude insects. British Standards BS6700: 1989, section two suggests that vents should be screened to prevent animals which enter the vent pipe from reaching the water supply. One way of doing this that has previous been suggested is to provide a screen across the lumen of the vent pipe.

There are problems with this arrangement, however, because the screen can corrode or get blocked.

Furthermore, it is not possible readily to check the condition of the screen and, if necessary, unblock it or replace it.

The present invention solves these problems by providing a tank having a vent pipe provided with a screen which presents a barrier to ingress of animals through the pipe to the tank, wherein the pipe has a section which is removable and provided with the screen, the removable section including a connector having sealing means, the connector removably connecting and sealing the section to the remainder of the pipe.

The present invention also provides a device for providing ingress of animals in a vent pipe of a tank as defined above, the device comprising a pipe section having a screen across the lumen thereof and a sleeve at an end thereof, the sleeve comprising a first O-ring sealingly engaged between the sleeve and the pipe section and adjacent said end of the pipe section, the sleeve being slidingly engaged with the pipe section and having a second, internal O-ring axially spaced from the first O-ring and extending beyond said end for sliding and sealing engagement with the vent pipe.

Reference is now made to the accompanying drawing, wherein the sole figure shows a longitudinal section of an embodiment of a tank venting device according to the present invention.

The venting device 10 comprises a pipe section 11 having first and second ends 12,13 and a lumen 14 extending therebetween. First and second detachable sleeves in the form of collars 15,16 are fitted over the first and second ends 12,13 of the tubular member respectively.

Each first collar 15 has an internal diameter which is slightly greater than the external diameter of the pipe section 11, so that the collar 15 can be fitted around the respective end 12,13 of the pipe section 11. First and second O-rings 17,18 are housed in axially spaced recesses (17a,18a) in the interior surface of each collar 15,16. The O-rings 17,18 are made from a resilient material. The first O-ring 17 of each collar 15,16 protrudes into the interior of the collar 15,16 to form a fluid-tight seal between the collar 15,16 and the exterior surface of the pipe section 11 when the collar is slid onto the pipe section 11. Each collar 15,16 can be readily detached from the pipe section 11 by pulling the collar 15,16 away from the pipe section 11.

The second O-ring 18 of each collar 15,16 also protrudes into the interior of the collar 15,16. The collar 15,16 can be slid onto the pipe section 11 in a reverse orientation to that shown, i.e. with the second O-ring 18 forming a seal between the collar 15,16 and the pipe section 11.

A porous screen 19 in the form of a pouch is fixed at its open end 20 to the interior surface of the second end 13 of the pipe section 11, with the closed end of the pouch pointing towards the first end 12 of the pipe section. The screen is attached across the lumen 14 of the pipe section 11, so that the lumen 14 is partitioned into two compartments 21,22.

The screen 19 has a pore size which is sufficiently large to allow liquid flow therethrough, but is small enough to present a barrier to the passage of insects, e.g. flies, across the screen. The screen 19 is corrosionresistant and is made of a metal gauze (e.g. stainless steel), but other structures are possible, e.g. a plastics netting. A metal screen is preferable, because rodents are less likely to chew through a metal screen.

Preferably, the pore size of the screen 19 is a maximum of 0.65 mm.

The screen 19 need not be pouch-shaped, but can, for example, be substantially planar and positioned radially across the lumen 14.

Furthermore, the screen 19 can be positioned anywhere between the ends 12,13 of the pipe section 11.

The venting device 10 is easily installed by first cutting the existing vent pipe 20a,20b of a tank (e.g. water tank overflow pipe), into a proximal piping length 20a which remains attached to the tank, and a detached distal piping length 20b. The first and second collars 15,16 can be slid onto the distal and proximal piping lengths respectively.

The pipe section 11 has substantially the same inner and outer diameters as the vent pipe 20a,20b. The first and second collars 15,16 can be slid onto the distal and proximal piping lengths respectively so that the second O-rings 18 form fluid-tight seals between the collars and the outer surfaces of the piping lengths 20a,20b. In this way, the venting device 10 forms a part of the overflow pipe.

Any animal entering the venting pipe and attempting to travel to the tank will be prevented from doing so by the screen 19.

The provision of collars 15,16, which slidably engage vent pipe sections 20a,20b, enables the device 11, to be readily detached from the vent pipe so that the screen 19 can be inspected, unblocked if necessary, and readily reinstalled. This also permits easy replacement of the device 10 if the screen is damaged.

Claims

1. A tank having a vent pipe provided with a screen which presents a barrier to ingress of animals through the pipe to the tank, wherein the pipe has a section which is removable and provided with the screen, the removable section including a connector having sealing means, the connector removably connecting and sealing the section to the remainder of the pipe.

2. A tank according to Claim 1, wherein the vent pipe is an overflow pipe.

3. Device for providing a barrier to ingress of animals in a vent pipe of a tank according to Claim 1 or 2, the device comprising a pipe section having a screen across the lumen thereof and a sleeve at an end thereof, the sleeve comprising a first O-ring sealingly engaged between the sleeve and the pipe section and adjacent said end of the pipe section, the sleeve being slidingly engaged with the pipe section and having a second, internal O-ring axially spaced from the first O-ring and extending beyond said end for sliding and sealing engagement with the vent pipe.

4. A device according to Claim 3, wherein the sleeve is a collar engaged with the outside surface of the pipe section.

5. A device according to Claim 3 or 4, wherein a second sleeve is provided at the other end of the pipe section, the second sleeve having a first O-ring sealingly engaged between the second sleeve and the pipe section adjacent said other end of the pipe section, the second sleeve being slidingly engaged with the pipe section and having a second, internal O-ring axially spaced from the first 0 ring and extending beyond said other end for engagement with a vent pipe section.

6. A device according to any preceding claim, wherein the screen is in the form of a pouch.

7. A tank according to Claim 1 or 2 including the device of any one of Claims 3 to 6.

8. A tank according to Claim 7 as appendant to Claim 6, wherein the closed end of the pouch points away from inlet of the vent pipe.

9. A device according to Claim 3 substantially as herein described with reference to the accompanying drawing.