WO1999006644A1

WO1999006644A1 - Conduit fitting for termites

Info

Publication number: WO1999006644A1
Application number: PCT/AU1998/000600
Authority: WO
Inventors: John Broomhead
Original assignee: Josu Corporation Pty. Ltd.
Priority date: 1997-07-28
Filing date: 1998-07-28
Publication date: 1999-02-11
Also published as: WO1999006644A8

Abstract

A conduit fitting (10) for joining two conduits embedded in a concrete slab and for preventing white ants from passing from a lower said conduit to an upper said conduit, the fitting comprising at least: a body (18) having an aperture therethrough and into which opposing ends of the conduits are positioned in use; and a flange (22) formed from a material impenetrable to termites and extending out from and around the periphery of the body (10), wherein the flange also extends into the aperture and around the periphery of the aperture.

Description

CONDUIT FITTING FOR TERMITES

Technical Background

The invention relates to a conduit fitting for joining two conduits embedded in a concrete slab, and for preventing white ants from entering a building. In particular, the device is used for joining two conduits and for preventing white ants from passing between any cracks or gaps which may occur in concrete between a lower conduit and an upper conduit.

Background of Invention Most concrete slabs for building foundations have pipes or other conduits which extend through the slab. These pipes are typically first placed on a construction site prior to the concrete being poured. When the concrete is poured forming a concrete slab, the concrete slab dries and shrinkage can occur which can cause cracks and gaps to form in the concrete slab, especially between a pipe wall and the concrete slab. These gaps and/or cracks, although small, can permit pests such as termites or white ants to pass up through the gaps and enter the building.

Currently, chemical treatments are used in an attempt to prevent white ants from entering the building via these gaps/cracks. The disadvantage of using chemical treatment however, is that it is expensive, environmentally unsound and must be repeated at regular intervals.

One known type of physical barrier that is currently used has a clip to which a mesh material is attached. The clip is located around a pipe and the mesh becomes embedded in the concrete slab. However, white ants can pass between the clip and the pipe if the clip doesn't secure well enough to the pipe.

Another known device for preventing white ants from entering the cracks between a pipe wall and a cement slab foundation, is disclosed in Australian Patent Application No. 37472/97. This document discloses a termite barrier which comprises a body having an aperture extending therethrough to receive an object therein and an outwardly extending flange portion surrounding the aperture, the flange portion being adapted to be at least partly embedded in a concrete structure through which the object extends. A disadvantage with this form of termite barrier is that it does not provide a conduit fitting for joining two conduits which are embedded in a concrete slab. Furthermore, it is suspected that termites may in fact degrade the piping and hence bypass the termite barrier.

Furthermore, this device must be fitted around the outside of an unbroken pipe rather than allowing two pipes to be in fluid communication with each other, hence, the device may not properly seal the gaps between the pipes and the concrete slab, allowing termites to enter the building.

It would be an advantage if at least preferred embodiments of the present invention provided a physical barrier which may overcome at least some of the above disadvantages. It would be a further advantage if embodiments of the invention provided the consumer with a useful or commercial choice.

Summary of the Invention According to a first aspect of the present invention, there is provided a conduit fitting for joining two conduits embedded in a concrete slab and for preventing white ants from passing from a lower said conduit to an upper said conduit, the fitting comprising at least: a body having an aperture therethrough and into which opposing ends of the conduits are positioned in use; and a flange formed from a material impenetrable to termites and extending out from and around the periphery of the body, wherein the flange also extends into the aperture and around the periphery of the aperture. Advantageously the ends of each conduit can abut the flange in the aperture. More advantageously the ends of each conduit abut the flange around the periphery of the conduit end. Preferably the conduit ends are positioned in the body in a close fitting arrangement with the body.

In one variation the body can have a pair of identical halves which are joined on opposite sides of the flange to define the fitting. However, more preferably the body is formed by being moulded on opposite sides of the flange simultaneously (eg. by injection moulding the body around the flange) .

Advantageously the conduit fitting is provided with a flange support member formed integrally with the body for providing support to the flange.

Advantageously, an abutment member is provided to cover the flange portion which extends into and around the periphery of the aperture, so providing a surface against which the opposite ends of each conduit abut. Typically the flange extends inwardly from the periphery of the aperture to at least the shell thickness of one of the two conduits.

Preferably the conduit fitting is a pipe fitting. More preferably the body and the aperture are circular.

Preferably the two conduits are pipes.

Preferably the flange is formed integrally with the pipe fitting.

Preferably the flange is disposed radially about the axis of a circular pipe fitting so as to prevent cracking of the slab.

Advantageously the flange is made from a non-corrosive material .

More advantageously the flange can be made of stainless steel or brass mesh which provides a surface to which wet concrete binds so as to prevent the concrete from cracking when it dries. When the fitting is formed from plastic, this mesh also advantageously enables the pipe to be effectively bond with the mesh.

Typically the diameter of the holes of the stainless steel mesh are less than 0.51 mm.

Typically the flange extends at least 20 mm from the periphery of the body.

Advantageously the body, abutment member and flange are made from any material which is resistant to degradation by termites. More advantageously the body, abutment member and flange are made from a material with a shore hardness of more than 80. Preferably the body, abutment member and flange are made from plastic material such as NYLON 12, NYLON 11 or any combination thereof. Advantageously the flange may be of any suitable shape when viewed in plan. For example, the flange can be square or rectangular, but is most preferably circular when viewed in plan.

According to a second aspect of the present invention, there is provided method for manufacturing a conduit fitting for joining two conduits embedded in a concrete slab and which in use prevents the passage of termites between said conduits, the method including the steps of locating a flange in a mould, and then introducing a plastic material within the mould to form a body having an aperture therethrough and in which the flange extends out from and around the periphery of the body, and also extends into the aperture and around the periphery of the aperture. Preferably the moulding step employs the technique of injection moulding.

Typically the injection moulding occurs at a temperature of 230°C.

Typically the injection moulding occurs within a pressure range of 70 to 180 MPa. Description of the Drawings Notwithstanding other embodiments that may be encompassed by the scope of the present invention as described broadly herein, one embodiment of the invention will now be described by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a perspective view of one embodiment of a device in accordance with the invention;

Figure 1A shows an enlarged view of the stainless steel mesh on the device of Figure 1;

Figure 2 is a perspective view of the device of Figure 1 located within a concrete slab and fitted to a pair of pipes ;

Figure 3 is a plan view of the device as shown in Figure 1;

Figure 4 is a plan view of the device of Figure 1 in- situ with a concrete slab;

Figure 5 is a cross-sectional view of the device of Figure 1 in situ; Figure 6 is a similar view to Figure 5, but where a gap has formed between the device and the concrete slab.

Detailed mode of invention Referring to the Figures, there is illustrated a conduit fitting in the form of a pipe fitting 10 for joining a first lower pipe 12 and a second upper pipe 14 which are embedded in a concrete slab 16 (as shown in Figure 2). The pipe fitting 10 prevents white ants from passing from the lower pipe 12 to the upper pipe 14. The pipe fitting comprises a body in the form of circular body 18 which has an aperture 20 extending therethrough and into which the opposing ends of the upper pipe 14 and lower pipe 12 are positioned in use. There is also provided a flange 22 which extends out from and around the periphery of the circular body 18, and which also extends into the aperture and around the periphery of the aperture (as shown in Figures 3 and 4 ) .

The flange in this example of the invention is made from stainless steel mesh which provides a surface to which wet concrete binds so as to prevent the concrete from cracking when it dries. In this example of the invention, the diameter of the holes of the steel mesh are .45mm in diameter. An enlargement of part of the mesh can be seen in Figure 1A as enlarged item 23.

It will be appreciated by those skilled in the art that the flange can be made of any non-corrosive material such as brass and does not have to be in the form of mesh although this is certainly preferable so that the flange binds to the concrete and so that circular body 18 binds to the flange 22. It will be further appreciated by those skilled in the art that the holes of the stainless steel mesh should be less than 0.51mm as this is the approximate head size of a termite. This prevents the passage of termites between the lower pipe 12 and the upper pipe 14.

The circular body 18 is also provided with a flange support member in the form of support flange 26 which is formed integrally with the circular body 18 and around flange 22 so as to provide structural support and integrity to flange 22.

The flange 22 can extend to the inside of the aperture 20, ie. extending within the internal periphery of the body 18, so that the end of the lower pipe 12 and/or the upper pipe 14 can wholly abut the flange 22 so as to sealingly engage the pipe fitting 10. This internally seals the conduits at their join. The lip 27 provides a surface against which the opposite ends of pipes 12 and 14 can more easily abut (eg. sealingly - for example using plumber adhesive or silicone sealant etc) .

In a preferred example of the invention, the flange 26 extends 40mm from the periphery of the body. The peripheral lip 27 typically extends inwards into the periphery of the aperture and surrounds that part of the flange 22 extending into the aperture. The aperture is typically 100mm in diameter. The thickness of the flange 22 when pipe fitting 10 is in front view, the flange 22 is typically 2mm.

In this example of the invention, the circular body 12 and the flange 26 are made from Nylon 12 with a Shore hardness of more than 80, which is resistant to degradation by termites . It will be appreciated by those skilled in the art that if the conduit fitting 10 is made from a material which is not resistant to degradation by termites (i.e. such as pvc pipe) the termites may degrade the conduit fitting and move along into the pipe fitting 10 so as to bypass the barrier and enter the building. This is particularly true for termites of the genus mastoterme darwinensis .

As shown in this particular embodiment, it is an advantage of the present invention, for the flange 22 to extend into the aperture and around the periphery of the aperture 20, as this provides a further barrier internal of the body 18, which prevents passage of termites. Furthermore, termites would be washed away by any fluids flowing downwardly from the pipe 14 to pipe 12. It will be further appreciated that the circular body 18 and flange 22 can be made from materials such as Nylon 11 or any other material which is resistant to degradation by termites .

It will be further appreciated by those skilled in the art that the flange 22 can be of any particular shape when viewed in plan, such as for example in square or rectangular shape, providing that it extends around the periphery of the circular body 18. Furthermore, it will be appreciated by those skilled in the art that the presence of the mesh holes in the mesh of flange 22, provide a means in which the plastic body 18 when injection moulded, binds the plastic to the mesh and forms around the mesh body so that it is formed integrally with the circular body 18.

In use, lower pipe 12 will be connected to a sewerage system prior to the concrete slab being poured. The end of pipe 12 is covered with a chemical adhesive prior to the pipe fitting 10 being placed onto the pipe 12 so as to sealingly engage the lip 27 to the pipe 12. Adhesive is put onto the other end of pipe 14 which is then inserted into the pipe fitting 10 so as to sealingly engage the lip 27. The pipe 12 and pipe 14 are sealed to the pipe fitting so that the contents of each pipe is in fluid communication with the other pipe.

The pipe fitting 10 is positioned at a height that will allow the flange 22 to become embedded in the concrete slab 16. The concrete slab is then poured and can surround the body 10 as shown in Figure 2.

As the concrete slab 16 dries it shrinks and gaps or cracks form through the concrete slab 16 adjacent to the pipes. Figure 6 shows a crack 28 that has formed in the concrete slab 16. It can be seen that termites cannot pass through the slab 16 via the crack 28. Further, the termites cannot eat through the pipe and/or flange 22 as the pipe fitting 10 and the support flange 26 are made from Nylon 11. Whilst the mesh is not essential (ie. flange 22 could simply be an extension for support 26 and lip 27 could be provided with mesh formed therein) , its presence makes the formation of the fitting 10 simpler, and the mesh strengthens the fitting. In addition, the mesh assists (enhances) the binding with wet concrete and provides an additional termite barrier.

It will also be appreciated that the pipe fitting 10 can also be used for other vermin such as ants and other crawling insects, and could be positioned in the eaves of buildings and/or ceilings. The device may also be located within any solid substance such as concrete plaster wall or ceiling boards, or floorboards where serviced pipes pass.

The device can be manufactured by an injection moulding process in which the flange 22 is inserted into a mould and then an injection moulding process occurs whereby molten plastic material flows around the flange 22 to form the pipe fitting 10. In one example of the method of manufacturing the pipe fitting the injection moulding occurs at a temperature of 230°C and at a pressure of 120MPa. It will be further appreciated by a person skilled in the art that numerous variations and/or modifications may be made to the present invention as shown in the specific embodiments without departing from the spirit and scope of the invention as broadly described. The present embodiments are, therefore to be considered in all respects to be illustrative and not restrictive.

Claims

1. A conduit fitting for joining two conduits embedded in a concrete slab and for preventing white ants from passing from a lower said conduit to an upper said conduit, the fitting comprising at least: a body having an aperture therethrough and into which opposing ends of the conduits are positioned in use; and a flange formed from a material impenetrable to termites and extending out from and around the periphery of the body, wherein the flange also extends into the aperture and around the periphery of the aperture.

2. A conduit fitting according to claim 1, wherein the conduit ends are positioned within the body in a close fitting arrangement.

3. A conduit fitting according to claim 1 or claim 2, wherein the ends of each conduit abuts the flange in the aperture .

4. A conduit fitting according to claim 3, wherein the ends of each conduit abut the flange around the periphery of the conduit ends .

5. A conduit fitting according to any one of the preceding claims, wherein the body has a pair of identical halves which are joined on opposite sides of the flange to define the fitting.

6. A conduit fitting according to any one of the preceding claims, wherein the body is formed by being moulded on opposite sides of the flange simultaneously.

7. A conduit fitting according to any one of the preceding claims, wherein the body is formed by injection moulding the body around the flange.

8. A conduit fitting according to any one of the preceding claims, wherein the conduit fitting includes a flange support member formed integrally with the body for providing support to the flange .

9. A conduit fitting according to any one of the preceding claims, wherein the conduit fitting includes an abutment member that covers the flange portion and which extends into and around the periphery of the aperture, so providing a surface against which the opposite ends of each conduit abut .

10. A conduit fitting according to any one of the preceding claims, wherein the flange extends inwardly from the periphery of the aperture to at least the shell thickness of one of the two conduits.

11. A conduit fitting according to any one of the preceding claims, wherein the conduits are pipes.

12. A conduit fitting according to claim 11, wherein the conduit fitting is a pipe fitting.

13. A conduit fitting according to any one of the preceding claims, wherein the flange is formed integrally with the pipe fitting.

14. A conduit fitting according to any one of the preceding claims, wherein the flange is disposed radially about the axis of a circular pipe fitting so as to prevent cracking of the slab.

15. A conduit fitting according to any one of the preceding claims, wherein the flange is made from a non- corrosive material.

16. A conduit fitting according to claim 15, wherein the flange is made of stainless steel or brass mesh which provides a surface to which wet concrete binds so as to prevent the concrete from cracking when it dries.

17. A conduit fitting according to claim 15, wherein the fitting is formed from plastic mesh, so that the mesh allows the pipe to bond with the mesh.

18. A conduit fitting according to claim 16 or claim 17, wherein the diameter of the holes of the stainless steel mesh are less than 0.51 mm.

19. A conduit fitting according to any one of the preceding claims, wherein flange extends at least 20 mm from the periphery of the body.

20. A conduit fitting according to any one of claims 9 to 19, wherein the body, abutment member and flange are made from a material which is resistant to degradation by termites .

21. A conduit fitting according to any one of claims 9 to 20, wherein the body, abutment member and flange are made from a material with a shore hardness of more than 80.

22. A conduit fitting according to any one of claims 9 to 21, wherein the body, abutment member and flange are made from a plastic material such as NYLON 12, NYLON 11 or any combination thereof .

23. A method for manufacturing a conduit fitting for joining two conduits embedded in a concrete slab and which in use, prevents the passage of termites between said conduits, the method including the steps of locating a flange in a mould, and then introducing a plastic material within the mould to form a body having an aperture therethrough and in which the flange extends out from and around the periphery of the body, and also extends into the aperture and around the periphery of the aperture.

24. A method according to claim 23, wherein the moulding step employs the technique of injection moulding.

25. A method according to claim 23 or claim 24, wherein the injection moulding occurs at a temperature of 230┬░C.

26. A method according to any one of claims 23 to 26, wherein the injection moulding occurs within a pressure range of 70 to 180 MPa.