GB2358199A

GB2358199A - Vermin exclusion device for a dainage/sewerage system

Info

Publication number: GB2358199A
Application number: GB0030772A
Authority: GB
Inventors: Colin Peach; Vernon Hall
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-12-24
Filing date: 2000-12-18
Publication date: 2001-07-18
Also published as: GB0030772D0; GB2358199A8

Abstract

An exclusion device for preventing the passage of vermin or the backwashing of solid matter through a water closet pan, comprising a normally-closed unidirectional valve fitted into the said outlet from or in the neighbourhood of, a water closet pan. The valve is suitably a top-hinged flap valve (20).

Description

2358199 VERMIN EXCLUSION DEVICE The present invention relates to a device

for isolating a section of a drainage or sewerage system from the remainder of the drainage or sewerage system, and more specifically, to a device for preventing vermin gaining access to premises, particularly domestic premises, by the foul water drainage system of the premises- It is a little known fact that the rat population, at least in urban environments, is increasing rapidly. It has been estimated that in urban areas of the United Kingdom at least, there is a rat within ten feet of any given person at any given time. Although in themselves rats are clean animals, they are vectors for a number of serious ailments and their presence in areas to which people have access is highly undesirable.

Rate and other vermin are known to gain access to the interior of buildings by passing through the water traps in lavatory pans contained in the building and it is an object of the present invention to prevent vermin from gaining access to the inside of building in this way.

Although the main purpose of the present invention is to prevent rats and/or other vermin from gaining access to domestic and other premises via soil 2 discharge pipes, the invention is effective to prevent the passage of other small creatures, such as amphibia and snakes, into premises and the term vermin is used herein to embrace all such creatures the presence of which within buildings is regarded as undesirable.

It is another object of the present invention at least to reduce the backwashing of solid matter into buildings when storm surge conditions occur in a sewerage system to which the buildings are connected- According to one aspect of the present invention there is provided an exclusion device for preventing vermin, as hereinbefore defined, from gaining access to the interior of a building via a fluid drainage system associated with the building, comprising a normally-closed unidirectional isolation valve adapted to open in the direction of the normal flow of fluid through the fluid drainage system, and means for mounting the isolation valve in a conduit forming part of the fluid drainage system.

The isolation valve is adapted preferably to fit within the outlet spigot of a water closet pan, however other suitable outlet spigots such as those exiting from a shower or sink are not beyond the scope of the invention.

3 The isolation valve may be a flap valve. Such a flap valve may comprise a top-binged flap valve which is such that the force of gravity tends to maintain the valve in its closed state. The flap valve may have more than one hinged closure member.

In some embodiments there are included means for biasing the valve towards its closure position- The valve may comprise or include a resilient portion whereby to conform to the inner surface of the spigot or pipe as it approached its open position.

The isolation valve may be so shaped as to conform to the inner surface of the spigot or pipe when it is in its open position whereby to mimmise the restriction to fluid flow therethrough.

Because it is an important consideration to not unduly restrict fluid flow through the spigot or pipe the valve is preferably adapted to open to a maximum extent so as to occlude the minimum area of the spigot or pipe.

In some embodiments the seat against which the valve abuts when it is in its closed position is compliant.

4 The device may be attached directly to the interior of a spigot or pipe and may be incorporated as the region itself is made initially- However, in a preferred embodiment the device is shaped and conformed to allow retrofitting to an existing water closet spigot and includes separate retaining means not initially forming part of the spigot, however, the retaining means may effectively form part of the structure of the region of the spigot when fitted.

According to a second aspect of the present invention there is provided a water closet pan the soil outlet from which is provided with a normally closed unidirectional isolation valve which is adapted to open in response to the flushing of the water closet pan.

According to a third aspect of the present invention there is provided a method of fitting an exclusion device as claimed in any preceding claim to a solid discharge pipe, in which a part of the pipe is removed to allow introduction of the said isolation valve transversely of the length of the pipe, and subsequently sealing the opening in the pipe with the isolation valve in position therein.

In all embodiments of the invention the inclusion of the device must not compromise the water tightness of the spigot or pipe.

The invention will now be described, by way of example, with reference to the accompanying drawings in which:

Figure 1 is a schematic cross-section of an isolation valve formed as an embodiment of the present invention; Figure 2 is a schematic end view of an isolation valve forming a second embodiment of the invention; Figure 3 is a schematic cross-section of a soil outlet spigot of a water closet prior to fitting of an isolation valve as shown in Figure 2.

Figure 4 is a schematic cross section of the soil outlet spigot of Figure 3 shown fitted with the isolation valve of Figure 2; and Figure 5 is a schematic longitudinal section of the soil outlet spigot of Figure 1 illustrating the working of the isolation valve.

Figure 5 is a schematic cross-section of an isolation valve formed as a further embodiment of the invention.

Figure 6 is a schematic cross-section of an isolation valve formed as a further embodiment of the invention.

Figure 7 is a schematic cross-section of an isolation valve formed as a still further embodiment of the invention and; Figure 8 is a cross-section of a further embodiment of the invention. Referring to Figure 1, an exclusion device for preventing vermin from gaining 6 access to the interior of a building via the soil outlet from a water closet pan or other conduit associated with a building consists of a tubular member 100 adapted to fit into the end of a sol 1 outlet spigot 10 1 from a water closet pan, not shown in the Figure, and be retained by a flexible collar 102 which also provides a seal between the soil outlet spigot 10 1 and a following length of conduit 103. The tubular member 100 has a hinged closure member in the form of a flap 20 attached to a hinge 33 via a pivot pin 33a which is held in brackets 3 la, 3 1b of which enly 3 la is visible in Figure 1 The isolation Vaive 1 shown in a closed position in which the flap 20 closes against a seal 60 which also acts as a stop. The flap 20 is weighted at its lower end by a weight 70 so as to keep the flap 20 in its closed position, but it is free to open soil outlet spigot 10 1 in response to the surge of water along the spigot when the water closet is flushed. The flap 20 and the seal 60 have a co- operating arcuate form such that when the flap 20 is in its open position, as shown by the dotted line the obstruction to the soil outlet spigot 101 is minimised. If so desired, the weight 70 can be replaced, or assisted by, a torsion or other spring associated with the pivot pin 33a about which the flap 20 pivots. Also, the collar 102 may be replaced by a flange and separate seal.

The lower ends of the brackets 3 1 a, 3 1 b serve as guide surfaces to prevent lateral movement of the flap 20 that might serve to weaken the join between the 7 hinge 33 and the flap 20. Not only does the flap 20 in its closed position hinder the passage of rats and other creatures, but in the event of a storm resulting in excess drainage to the sewerage system to which the water closet pan is connected, or other backwashing of sewerage into the soil outlet spigot 50, at the least the passage of solid waste into the premises in which the water closet pan is situated is prevented. If the seal is made of a compliant matenal then the higher the back pressure, which occurs in the event of such storm surge, the better the seal.

Referring to Figure 2 there is shown an isolation valve generally indicated 1 comprising an arcuate support 10 attached to a disc shape flap 20 by a generally H-shape connector 30. The H-shape connector 30 includes two generally L-shape vertical legs 31a, 31b, by which the connector 30 is suspended from the support 10joined by a transverse strut 32. A hinge 33 depends from the transverse strut 32 and is pivotally attached to the flap 20 as shown best in Figure 4.

ReferTing now to Figure 3 there is shown a cross section of an outlet spigot 50 of a water closet. The spigot 50 is shown with a section 50a removed to provide a gap that is large enough and shaped so as to allow insertion of the 8 isolation valve 1 of Figure 2.

Figure 4 shows the outlet spigot 50 of Figure 3 with the isolation valve of Figure 2 fitted. It can be seen that the arcuate support 10 is shaped so as to conform to the outer surface of the spigot 50 and the width of the connector 30 as defined by the strut 32 is approximately equal to the gap in the spigot 50- In some embodiments the connector is formed from a resilient material and is initially longer than the gap in the spigot so that when fitted the strut 32 deforms and then tends to push the brackets 3 1 a, 3 1 b outwardly against the exposed ends of the spigot 50 whereby to hold the isolation valve 1 firmly in place; in any case the isolation valve must be fitted so as not to compromise the water tightness of the spigot 50. When fitted the arcuate support 10 and the connector 30 effectively form part of the spigot 50.

Referring now to Figure 5 there is shown a schematic side view of the embodiment shown in Figure 4 to illustrate the working of the isolation valve 1.

Because the flap 20 is a disc and is within a cylindrical tube of only slighly greater diameter, in order for it to be able to open to a point approximately 9 orthogonal to its closed position (shown in phantom) the flap 20 must pivot into a wider tube as is the case in Figure 4.

Alternative arrangements for allowing a disc-shape one-way valve unit to be incorporated within a soil outlet spigot without the need for the valve to be immediately adjacent a wider tube are shown in Figures 6 and 7.

Figure 6 shows an isolation valve similar to that shown in Figure 2. The flap 120 as a whole may not be able to pivot, however a flap portion 120a is mounted within the flap 120 and can pivot relative to the flap 120. The dimensions of the flap portion 120a are such as to allow it to pivot to a point approximately orthogonal to its closed position before it contacts the wall of the spigot.

Figure 7 shows an alternative embodiment that is also similar to that shown in Figure 2. The disc-shape flap 320 is able to pivot as described in relation to Figure 5, however the flap 320 includes a perimetral resilient portion 320a that allows the perimeter of the flap to conform to the inner surface of the spigot as it opens.

Referring to Figure 8, there is shown another form of isolation valve embodying the invention which is similar in some respects to that shown in Figure 1 in that it is inserted into an end of the soil outlet spigot from a water closet pan, or other length of conduit, and similar reference numerals are used for similar components. The tubular member 100 is replaced by a clip 80 which has a portion 81 which prOjects into the soil outlet spigot 50. Also, the brackets 3 1 a, 3 1 b which carry the hinge pin 33 are so shaped that they co-operate with a hinge bracket 82 on the flap 20 to act as a stop for the flap 20.

Claims

1) An exclusion device for preventing vermin, as hereinbefore defined, from gaining access to the interior of a building via a fluid drainage system associated with the building, comprising a normally closed unidirectional isolation valve adapted to open in the direction of the normal flow of fluid through the fluid drainage system and means for mounting the isolation valve in a conduit forming part of the fluid drainage syatem.

2) An exclusion device according to Claim 1 wherein the isolation valve includes at least one hinged closure member.

3) An exclusion device according to Claim 2 wherein there is included a single top-hinged closure member such that the force of gravity acts to urge the closure member towards a closed position.

4) An exclusion device according to any of Claims 1 to 3 wherein there is included means for urging the isolation valve towards a closed condition.

5) An exclusion device according to any preceding claim wherein the isolation valve includes a closure member comprising or having a resilient portion adapted to conform to the inner surface of the conduit as the closure member approaches its open position.

6) An exclusion device according to any of Claims 1 to 4 wherein the isolation valve includes a closure member so shaped as to conform substantially with the inner surface of the conduit when the closure member is in its open position thereby to minimise the restriction to the flow of the fluid through the conduit.

7) An exclusion device according to any preceding claim wherein there is included a resileo't seal against which the closure member abuts when it is in the closed position.

8) An exclusion device according to any preceding claim wherein the isolation valve is an integral part of the said conduit.

9) An exclusion device according to any of Claims 1 to 7 wherein the mounting for the 1 isolation valve is adapted to be fitted into the said conduit.

10) An exclusion device according to Claim 9 wherein the mounting for the isolation valvo, comprises a section of conduit adapted to fit into the said conduit and means for attachOl the hinge of the hinged closure member to the inner surface of the section of conduit.

11) An exclusion device according to Claim 9 wherein the means for mounting the isolation' : 1 valve in the said conduit comprises a clip adapted to be fitted over the end of the said conduit, the said clip including a portion which projects into the said conduit and carri si the hinge of the hinged closure member.

12) An exclusion device according to any preceding claim wherein the said conduit is the $oil outlet from a water closet pan.

13) A water closet pan, the soil outlet from which is provided with an exclusion device according to any of Claims 1 to 11.

13 14) A method of fitting an exclusion device according to any preceding claim to the fluid discharge conduit, comprising the operations of removing a section of the conduit to allow the insertion in the conduit of the mounting for the isolation valve and subsequently sealing the conduit in the way of the portion of the conduit which was removed to permit the insertion of the mounting for the isolation valve.

15) An exclusion device for preventing vermin as herembefore defined from gaining access to the interior of a building via a foul water drainage system associated with the building substantially as hereinbefore described and with reference to the accompanying drawings.

16) A water closet pan, the soil outlet pipe from which is provided with a normally closed isolation valve substantially as hereinbefore described and with reference to the accompanying drawings.

17) A method of fitting an exclusion device to a fluid flow conduit associated with a building to prevent vermin as hereinbefore defined from gaining access to the interior of the building substantially as hereinbefore described and with reference to the accompanying drawings.