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Title:
IMPROVEMENTS TO MANHOLE ASSEMBLIES
Document Type and Number:
WIPO Patent Application WO/2014/062072
Kind Code:
A1
Abstract:
The specification describes improvements to manhole assemblies, including brackets to facilitate connecting a sewer to a manhole, a kitset manhole assembly, and methods of using the foregoing.

Inventors:
FULLER BRIAN (NZ)
MCLACHLAN BRUCE (NZ)
Application Number:
PCT/NZ2013/000191
Publication Date:
April 24, 2014
Filing Date:
October 21, 2013
Export Citation:
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Assignee:
FULMAC PRODUCTS LTD (NZ)
International Classes:
E03F5/02; E02D29/12; E03F3/04; E03F3/06
Foreign References:
JPH07317111A1995-12-05
GB1581051A1980-12-10
Attorney, Agent or Firm:
MACASKILL, David et al. (Private Bag 3140Hamilton, 3240, NZ)
Download PDF:
Claims:
WHAT WE CLAIM IS:

1. A bracket to facilitate connecting a sewer to a manhole, the bracket including: a joint between a first pipe and a second pipe,

wherein the first pipe has a first end within the joint and a second end outside of the joint,

wherein the second pipe has a first end within the joint and a second end outside of the joint so as to facilitate connecting the second pipe to a bowl within the manhole,

characterised in that the joint is configured to enable the first and second pipes to be rotated about their respective longitudinal axis so as to change the angle between the first pipe and the second pipe.

2. The bracket as claimed in claim 1 , including a fastener to secure the bracket to a manhole.

3. The bracket as claimed in e claim 2, wherein the fastener is a clamp.

4. The bracket as claimed in claim 3, wherein the clamp is provided by a main body of the bracket, a clamping portion, and a plurality of fasteners to hold the main body and clamping portion together.

5. The bracket as claimed in any one of claims 1 to 3, wherein the joint is a ball and socket type joint.

6. The bracket as claimed in any one of claims 1 to 4, wherein the first end of the first pipe is at an oblique angle to the length of the first pipe.

7. The bracket as claimed in any one of claims 1 to 5, wherein the first end of the second pipe is at an oblique angle to the length of the second pipe.

8. The bracket as claimed in any one of claims 1 to 6, wherein the joint is configured to limit movement of the second pipe so that the second pipe can only rotate around its longitudinal axis.

9. The bracket as claimed in any one of claims 1 to 7, wherein the joint is

configured to allow the first pipe to rotate about its longitudinal axis.

10. The bracket as claimed in any one of claims 1 to 9, including a sealing

portion.

11. The bracket as claimed in any one of claims 1 to 10, including a mounting to support the joint.

12. The bracket as claimed in any one of claims 1 to 11, wherein the joint is positioned with respect to the bracket such that when the bracket is secured to a wall of the manhole the joint is substantially in line with a plane defined by the wall.

13. The bracket as claimed in any one of claims 1 to 12, wherein the joint is configured to maintain the first ends of the pipes substantially in contact with each other.

14. The bracket as claimed in any one of claims 1 to 13, including a fastener to hold the first and second pipes at a fixed angle with respect to each other.

15. The bracket as claimed in claim 14, wherein the fastener to hold the first and second pipes at a fixed angle with respect to each other is a clamp.

16. The bracket as claimed in claim 15, wherein the clamp is a collar and at least one rotational fastener.

17. The bracket as claimed in any one of claims 1 to 16, wherein the second pipe has a length such that it extends beyond an inner surface of a wall of the manhole and into a cavity in the manhole.

18. A method of connecting a sewer to a manhole using a bracket, wherein the bracket includes between a first pipe and a second pipe, and wherein the first pipe has a first end within the joint and a second end configured to be connected to a sewer, and wherein the second pipe has a first end in the joint and a second end outside of the joint, and wherein the joint is configured to enable the first and second pipes to be rotated about their respective longitudinal axis so as to vary the angle between the first pipe and the second pipe,

the method including the steps of:

(a) rotating the first and second pipes about their respective

longitudinal axis so as to change the angle between the pipes,

(b) connecting the second end of the first pipe to the sewer.

19. The method as claimed in claim 18, including the step of creating an aperture in the manhole prior to step (a).

20. The method as claimed in either one of claims 18 or 19, including the step of connecting the second end of the second pipe to a bowl inside the manhole.

21. The method as claimed in any one of claims 18 to 20, including the step of using a fastener to secure the bracket to the manhole.

22. A method of connecting a sewer to a manhole, using a bracket as claimed in any one claims 1 to 7.

23. A bracket as substantially described herein with reference to the best modes section of the attached specification and accompanying drawings. A method of connecting a sewer to a manhole, as substantially described herein with reference to the best modes section of the attached specification and accompanying drawings.

Description:
IMPROVEMENTS TO MANHOLE ASSEMBLIES

TECHNICAL FIELD

The present invention relates to improvements to manhole assemblies, including a method of construction and a kitset of parts to form a manhole assembly. BACKGROUND ART

Manhole assemblies are used to provide access to waste water and storm water systems, to act as points of connection between different systems, and to facilitate redirection of the material being carried to treatment / disposal plants.

Historically, manhole assemblies were made out of concrete or bricks, onsite. Alternatively manholes can be pre-cast, moved onto site, and installed in position. However, the materials used meant that they can be overly heavy and difficult to manoeuvre into place.

As a solution, kitset manholes have been constructed. Generally, these include a top portion providing an access point (manhole), a main body portion formed from at least two cylindrical components which engage with each other, and a base providing a number of connection points.

However, these kitset manholes have a number of inherent limitations. The first of these is that they are prone to "float" once installed in the ground. That is, the manholes rise in the ground. This can lead to cracking of the connection pipes secured to the base, causing leakage and health risks.

In addition, given that the main body is formed from cylindrical sections, it means that these kitsets are bulky. This increases the cost of transportation.

Yet another limitation of many available manhole kitsets is that they have a fixed number of inlets and outlets, at defined positions around the base's circumference. Therefore users are limited to how they will connect adjacent manholes along a sewer system.

Further, it is a regulatory requirement that there can be no bends in the pipes between adjacent manholes. Therefore, two adjacent manholes must have a line of sight connection. In practice, it is a considerable amount of work to lay pipes to provide the required line of sight connection.

Therefore, it would be advantageous to have a manhole which is lightweight and compact therefore making it easier to transport. In addition, it would be advantageous to have an manhole that is easier to construct and make watertight.

It would also be advantageous to limit or reduce floating of the manhole once it is installed in the ground.

Further, it would be useful to have an improved system to connect manholes. Alternatively, it is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country. It is acknowledged that the term 'comprise' may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive meaning - i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only. DISCLOSURE OF INVENTION

According to one aspect of the present invention, there is provided a kitset to construct a manhole, the kitset including:

(a) a top portion,

(b) a base, and

(c) a wall module to be secured between the base and the top portion, characterised in that the kitset includes at least two wall segments which are secured to each other along their side edges to form the wall module.

According to one aspect of the present invention, there is provided a method of constructing a manhole, including the following steps in any order: (a) positioning a base,

(b) securing a wall module to the base,

(c) securing a top portion to the wall module, characterised by the step of securing at least two wall segments to each other along their side edges to form the wall module.

Throughout the present specification reference to the term "manhole" should be understood as meaning a structure which allows a person to access an underground utility system. This is as should be understood by those skilled in the art.

The manhole may allow access to a sewer or drain. In this embodiment, the manhole may connect two or more conduits in the sewer. This aspect should become apparent from the ensuing description. Reference will now be made herein to use of the manhole in a sewer and to the conduits as sewer pipes. Alternatives are envisaged including storm water pipes, or conduits carrying telecommunication or electrical cables.

Throughout the present specification reference to the term "base" should be understood as meaning a component which will provide stability to the manhole once constructed.

The base may be made from a rigid sheet material such as a reinforced plastics material or a concrete slab.

The base may assist in stabilising the manhole once constructed by supporting the wall module and top portion of the manhole. The base may be any shape or material which is able to assist in stabilising the manhole.

The base may also be able to withstand the weight of dirt and the like around the manhole once installed. In a preferred embodiment, the base may be configured to engage the wall module of the kitset. In this embodiment the base includes a portion that corresponds to the shape of, and preferably mates with, the main body. Therefore in the preferred embodiment the base may have a mating portion with a cylinder shape. The mating portion has a channel to receive the bottom edge of the main body as will be discussed below.

In a preferred embodiment the base may have a bowl. The bowl facilitates attachment and connection of the manhole to a sewer, and forming a fluid pathway along the sewer. Preferably the bowl may fit within or be integral to the mating portion.

Therefore the bowl may be connected to the base after installation of the base in the ground.

In a particularly preferred embodiment the height of the bowl relative to the base may be adjustable. In this embodiment, the kitset may include a telescoping or screw thread spacer, to adjust the height of the bowl relative to the base.

Adjusting the height of the bowl relative to the base is important as it may facilitate to connecting sewer pipes to the manhole. In addition, it may help to comply with regulatory requirements regarding flow gradients through the manhole and sewer pipes. This aspect of the present invention should become clearer from the ensuing description.

The kitset may also include spacers. The spacers help to position the bowl relative to the mating portion of the base, and also secure the bowl in position preventing unwanted movement. The spacers may be wedges which fit between the mating portion and bowl, or braces which engage the top edge of the bowl and press against the mating portion.

Throughout the present specification reference to the term "guards" should be understood as meaning components that stop, prevent, or limit material getting between the edge of the bowl and the base. Therefore the guards sit over top of the spacers. The guards may have a shape which prevents fluid getting between the bowl and the sides of the mating portion.

Throughout the present specification reference to the term "wall module" should be understood as meaning a component of the manhole between the base and the top portion.

Preferably the wall module may be a cylinder. However it is also envisaged that the main body could have a square cross section.

In the preferred embodiment the main body may be formed from at least two wall segments secured to each other along their side edges. It will be understood that in preferred embodiments, the wall segments are sections of a cylinder.

In a preferred embodiment the wall segments may have flanges extending away from the wall segments. In one embodiment the flanges may extend substantially perpendicular to a plane normal to the outside surface of the wall. The flanges of adjacent wall segments lie flat against each other to assist in securing the wall segments to each other. They may also assist in ensuring that the manhole is fluid tight.

In a particularly preferred embodiment the wall segments may have identical dimensions. Therefore a kitset of parts need only have one type of wall segment. This limits the parts needed to manufacture the manhole. It may also make it easier to assemble a manhole according to the present invention.

In a particularly preferred embodiment the kitset may include a ladder segment. In this embodiment, the ladder segment may be configured to be secured to the side edges of two wall segments. It therefore forms part of the wall module.

The ladder segment may also have flanges corresponding to those of the wall segments.

In a particularly preferred embodiment the at least two wall segments and the ladder segment may be secured to each other to form a main body having a cylinder shape.

In a particularly preferred embodiment the kitset may include a plurality of wall modules. In this embodiment each wall module may be constructed from wall segments and ladder segments as discussed above. However, each main body segment can engage with a corresponding main body section above and/or below. Having a plurality of wall modules facilitates creating a manhole assembly of variable height.

In a preferred embodiment the kitset may include a plurality of connectors.

Throughout the present specification reference to the term "connector" should be understood as meaning a component which facilitates connecting two wall modules together.

In a preferred embodiment, the connectors may have a circle shape. However it is also envisaged that the connector can be formed from two or more pieces connected together to have a circle or other shape. It is also envisaged that the main body could be square or triangular. The key is that the connector facilitates connecting two wall modules.

Preferably, the connector may have grooves to receive the respective bottom and top edges of the two main body sections. It is also envisaged that the ring connectors can fit over around the outside edges of the main body sections, or press against the internal surface of the main body sections.

Throughout present specification reference to the term "top portion" should be understood as meaning the top component of the manhole once constructed. Preferably, the top portion may provide an access point to the manhole.

In a particularly preferred embodiment the top portion may be configured to receive a detachable cover. This allows people access the inside of the manhole, and facilitates sealing to prevent unauthorised access.

In a preferred embodiment, the kitset may include an anchor. Throughout the present specification to the term "anchor" should be understood as meaning a component which provides resistance to the manhole floating once installed in the ground.

Floating is a term of the art referring to movement of the manhole once installed in the ground. The manhole moves vertically therefore damaging connections to sewer pipes.

In one embodiment the anchor may be at least one member extending away from the manhole. The member(s) may be integral to wall segments, the base, or top portion. In an alternative embodiment the anchor may be at least two members which engage via a screw thread. In this embodiment, the members may extend through apertures in the flanges of adjacent wall segments. Therefore, in this embodiment the anchor assists in securing the wall sections relative to each other as well as preventing floating.

Alternatively, the anchor may be formed during molding of the main body sections, base, or top portion.

According to another aspect of the present invention, there is provided a bracket to facilitate connecting a sewer to a manhole, the bracket including: a) a fastener to secure the bracket to the manhole, b) a joint between a first pipe and the bracket, c) wherein the first pipe has a first end within the joint and second end outside of the joint, d) and wherein the joint is configured to enable the angle between the first pipe and the bracket to be changed.

According to another aspect of the present invention, there is provided a method of connecting a sewer to a manhole, the method using a bracket that includes a fastener to secure the bracket to the manhole, a joint between a first pipe and the bracket, and wherein the first pipe has a first end within the joint and a second end configured to be connected to a sewer, and wherein the joint is configured to vary the angle between the first pipe and the bracket, the method including the steps of: a) creating an aperture in the manhole; b) securing the second end of the first pipe to the manhole; c) changing the angle between the first pipe and the bracket; d) connecting the second end of the first pipe to the sewer.

According to another aspect of the present invention, there is provided a method of connecting a pipe to a manhole, the method including the steps of:

(a) positioning a bracket relative to an aperture in the manhole;

(b) securing the bracket in place; characterised in that step (b) creates a seal between an edge of the aperture in the manhole and a surface of the bracket. According to another aspect of the present invention, there is provided a bracket to secure a pipe to a manhole, the bracket including:

(a) a main body,

(b) a mounting to receive and support the pipe, characterised in that the main body has a surface to create a seal between the bracket and an aperture in the wall of the manhole.

In a preferred embodiment, the bracket may be used to secure a pipe to the wall of a manhole constructed using the kitset and method described above. Reference herein will be made as such.

In that embodiment the kitset may include a bracket as described herein. However it is also envisaged that this aspect of the present invention could be used with other supports and manholes, or even after applicants. These include manholes constructed using concrete, or other materials. In addition, this aspect of the present invention may be used with manholes formed from one rotationally molded component, pre-cast concrete manholes, or those having bodies formed from one or more integral cylinders.

In a preferred embodiment the aperture may be formed via techniques known to those skilled in the art. These may vary depending on the materials from which the manhole is made. For instance, in the embodiment where the manhole is made from polyethylene, a knife or other cutting implement may be used to form the aperture. Alternatively, where the manhole is made from concrete, an aperture can be made with a mechanical saw and friction disk. In a preferred embodiment, the bracket may have a fastener to connect the bracket to the manhole.

Preferably the fastener may be a clamp. In this embodiment, the edges of the aperture in the manhole may be inserted between the clamp and the main body. Rotational fasteners can be tightened to securely attach the bracket to the manhole.

Alternatively screws may extend through the bracket and into the wall of the manhole. Tightening the screws causes the body to press against the manhole and forces the surface of the bracket to create a seal.

In a particularly preferred embodiment, the main body may have a projection which can bear against the edges of the aperture. In this embodiment, the projection may be substantially at or near the side edges of the main body.

The fastener causes the bracket to be pulled tightly against the edges of the aperture. This causes the projection to sit tightly against the wall of the manhole, thereby forming a seal. In one ennbodiment the projection may be formed from a deformable and/or waterproof material. This ensures that the projection can form a seal about the aperture.

In a preferred embodiment, the bracket may have a mounting to support one or more pipes.

In a preferred embodiment the mounting may attach two pipes to each other forming a fluid pathway.

In a particularly preferred embodiment the mounting may facilitate variation of the angle between the two pipes. In this embodiment, the end faces are not at right angles to the length of the pipe but instead are at corresponding oblique angles to the length of the pipe.

Preferably the mounting may restrict the range of movement of the pipes. For example, one of the pipes may be able to rotate only around its longitudinal axis. In contrast, the second pipe may be able to rotate around and about its longitudinal axis. The combined movement of the pipes causes the second pipe to outline a cone centered at the mounting. This facilitates connection of sewer pipes to the first pipe at variable angles.

Also, the rotation of the first and second pipes about their longitudinal axis enables the corresponding oblique faces of the ends of the pipes to be kept in alignment. Therefore the angle between the pipes can be easily varied whilst the end faces remain in contact. This helps to facilitate a provision of fluid tight seal at the point where the end faces meet.

The preferred embodiment is a ball and socket type joint. In this embodiment, the end of each pipe may include one section of the ball forming part of the joint. However, this is not meant to be limiting and other ways varying the angles between the pipes are envisaged.

The ends of the pipe forming the ball and socket joint are positioned inside a cavity in the mounting. The cavity provides the socket part of the joint. It is also envisaged that the bracket may have a mounting to attach two pipes to each other at a fixed angle.

In yet a further embodiment, the first and second pipes may not have oblique faces, nor may they be able to rotate relative to each other. Rather, the joint may be configured to facilitate changing of the angle between the first and second pipe. The joint is in the form of a flexible gusset. That enables the pipes to move with respect to each other so is to change the angle between them. A clamping portion may secure the pipes in position. Therefore, the foregoing should be seen as in no way limiting the scope of the present invention.

According to another aspect of the present invention, there is provided a method of attaching a pipe to a manhole having a bowl, the method including the steps of:

(a) removing a section of the bowl in a manhole;

(b) creating an aperture in the side wall of the manhole; characterised by the step of: securing a transitional section to the edges of the bowl from where the section was removed.

According to a further aspect of the present invention, there is provided a transitional section for use in the method described above. In a preferred embodiment, the method of this aspect of the present invention may be used with the manhole kitset described above. Therefore, the invention can be used to connect a plurality of pipes to the manhole.

In a preferred embodiment the step of removing a section of the manhole assembly's bowl may involve cutting a section of the bowl.

In a particularly preferred embodiment the cut section may be triangular. Although, alternatively this section may be curved or square.

Preferably, a pipe may be secured to the aperture using a joint according to another aspect of the present invention as discussed above. However, alternative embodiments are envisaged including a pipe secured directly to the side wall of the manhole or using joints other than those according to another aspect of the present invention.

In a preferred embodiment, the transitional section may have a first portion corresponding to the shape of the section cut from the bowl, and a second portion configured to be secured to a pipe extending through an aperture in the manhole.

In a particularly preferred embodiment, the transitional section's first portion may have dimensions which allow the height of the second portion to be changed relative to the bowl.

This allows this aspect of the present invention to facilitate connecting pipes to a manhole at variable heights.

It should be appreciated that this feature of the connector is particularly beneficial as it facilitates connecting a sewer pipe to the manhole at variable heights above the bowl. This makes installing manholes in sewer systems much easier. Preferably, the transitional section may be secured to the edge of the bowl and the aperture by techniques known to those skilled in the art. These may include plastic welding, adhesives or other sealants suitable for use in sewage or storm water systems. In a preferred embodiment the present invention may include a ramp.

Throughout the present specification reference to the term "ramp" should be understood as meaning a component which provides a path between the transitional section and a bowl in a manhole.

The ramp may assist the flow of fluid through a manhole, and to ensure that particulate / suspended matter is retained in the fluid.

Preferably, the ramp may be formed from an extrusion of variable length. In this embodiment, the extrusion may be cut to the desired length, depending on the height of the transitional section above a bowl in a manhole. Again, this facilitates connecting pipes to a manhole at variable heights. It should be clear from the foregoing description that the present invention has a number of advantages.

Firstly, the side wall segments forming a wall module are compact. These are able to be stacked together in a nesting arrangement. This decreases the volume of the manhole and reduces transportation costs in comparison to prior art. In addition, the kitset according to the present invention is easily assembled, using minimal tools.

The configuration of the parts forming the kitset and the unique interaction of these assists in making a manhole assembly fluid tight.

Yet a further advantage of the present invention is that it allows a person to easily connect a manhole along a sewer at variable angles. This is a significant improvement over the available prior art manholes.

Further, this fluid connection can be easily made at the side wall of the manhole, thereby ensuring that the present invention complies with regulatory requirements. BRIEF DESCRIPTION OF DRAWINGS

Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which:

Figure 1A is a plan view of a base; Figure 1 B is a side view of a base;

Figure 2A is a plan view of a wall module;

Figure 2B is a side view of a side wall segment;

Figure 2C is a side view of a ladder segment through line A-A;

Figure 2D is an enlarged view of a section of Figure 2A; Figure 3A is a side view of a top portion through line B-B in Figure 3B;

Figure 3B is a plan view of a top portion;

Figure 4A is an end on view of an anchor;

Figure 4B is a side view of an anchor;

Figure 5 is a cross sectional view of a ring connector; Figure 6 is a side view of a bracket of the present invention; Figure 7 is a side cross sectional view of a manhole according to the present invention;

Figure 8 is a side cross sectional view of a bowl being installed in a manhole; Figure 9 is an exploded view of several components of the manhole; and Figure 10A is an end on view of a transitional section including a ramp; Figure 10B is a plan view of Figure 10A; and

Figure 1 1A is a side review of a component of a bracket of the present invention;

and

Figure 11 B is a side view of Figure 11 A in an alternate configuration. BEST MODES FOR CARRYING OUT THE INVENTION

The following discussion of the Figures generally describes a method and kitset to construct a manhole (1 ) according to the present invention with reference to the order in which the components are assembled.

Throughout the Figures like numerals refer to like components. A base (2) has a plinth (3) and cylinder shaped extension (4) as shown in Figures 1A and 1 B

Ridges (5) are secured to the side of the cylinder shaped extension (4) and the plinth (3). The ridges (5) provide strength and reinforcing to the cylinder shaped extension (4). The base (2) can be installed in the ground (indicated by (6) in Figure 7). The position and height of the manhole will be determined with regard to a sewer (not shown) to which the manhole is to be connected). This occurs using techniques as should be known to those skilled in the art.

A ring connector (7) has a first groove (8) which receives top edge (9) of the cylinder shaped extension (4). The ring connector (7) has a second groove (10) facing away from the base (2). Wall modules (11) are formed from a first side wall segment (12), a second side wall segment (13), and a ladder segment (14).

The side wall segments (12,13) and ladder segment (14) each have corresponding flanges (15). The flanges (15) extend away from the segments (12, 13,14).

Flanges (15) have corresponding protrusions (16) and channels (17) that are best seen in Figure 2D. The protrusions (16) and channels (17) extend along the entire length of the flanges (15). The protrusions (16) and channel (17) help to seal the manhole (1) once constructed.

Wall Segment (12,13) are symmetrical so that they can be used interchangeably.

In addition the side wall segments (12,13) can be used upside down. This means that the kitset of the present invention may be easier to assemble.

The flanges (15) have apertures (18).

Anchors (19) are elongate members having a first end (20) and second end (21). The apertures (18) and first and second ends (20,21 ) have corresponding shapes.

The first or second end (20, 21 ) is inserted through an aperture (18). Portion (22) is narrower than the apertures (18). This allows the anchors to be rotated to bring ends (20, 21) out of alignment with the apertures (18) and thereby secure the anchor (19).

The anchors (19) provide resistance to floating of the manhole (1 ) in the ground once assembled and installed.

Ladder segments (14) have rungs (23) which can be seen in Figure 2C. The rungs (23) facilitate access to the bottom of the manhole (1).

The wall module (11) is positioned over the ring connector (7). The bottom edge (24) of the wall module (11) is inserted into the second groove (6).

Multiple wall modules (11) are connected above and below each other using ring connectors (7). This facilitates forming a manhole (1) of variable height.

A top portion (25) is shown in Figures 3A and 3B. The top portion (25) has a downward facing groove (26) to receive top edge (27) of a wall module (11). The top portion (25) has an aperture (28). This facilitates access inside the manhole (1) once constructed.

The aperture (28) can be sealed via a cover (not shown).

Due to the nature of sewers, the angles at which pipes are connected to a manholes (1) can vary. Therefore is useful to have a way to facilitate connection of sewer pipes to a manhole (1 ) at variable angles.

The following description describes how the manhole (1) is connected to two or more pipes forming part of a sewer (none of which are shown in the Figures).

A bracket (29) is used to facilitate attachment of sewer pipes (not shown) to the manhole (1) at variable angles. The bracket (29) has a main body (30), a first clamping portion (31), & a first pair of rotational fasteners (32A & 32B). A bead (33) runs around the perimeter (34) of the main body (30).

An aperture (35) is made in the manhole (1). This may be in either a wall module (11) or the cylinder shaped extension (4). The height at which the aperture (35) is made will depend on the sewer pipe to which the manhole (1) is to be connected. This is as should be understood by one skilled in the art.

The bracket (29) is positioned so that the edges of the aperture (35) are between the main body (30) and the first clamping portion (31). The first pair of rotational fasteners (32A & 32B) are tightened. This squeezes the first clamping portion (31) to the main body (30) thereby clamping the manhole between these to secure the bracket (29) to the manhole (1).

The bead (33) abuts the surface of the cylinder shaped extension (4) near the edge of the aperture (35). Tightening the fasteners (32A & 32B) ensures that the bead (33) is tightly pressed against the cylinder shaped extension (4) to form a seal. The seal prevents fluid leaking in and out of the manhole (1) around the bracket (29).

The main body (30) has a curved socket (38). The socket (38) and second clamping portion (39) define a cavity indicated by (40). The cavity (40) can receive a mounting (76) to support a first pipe (36) and second pipe (37). The mounting (76) also facilitates variation in the angle between the pipes (36,37). This should become clearer from the following description.

First pipe (36) has an end (41). The end (41) is cut to be at an oblique angle to the longitudinal axis (Y) of the pipe (36).

A flange (42) extends away from the end (41). Flange (41) has an inside face (43) and an outside face (44). The inside face (43) is flat.

Second pipe (37) has an end (45). The end (45) is cut to be at an oblique angle to the longitudinal axis (X) of the second pipe (37). Flange (47) extends away from the end (45). Flange (47) has an inside face (48) and an outside face (48). The inside face (48) is flat.

A collar (77) sits over the flanges (42, 47). The collar (77) holds inside faces (43, 48) together to provide a fluid seal. However the pipes (36, 37) can still rotate relative to each other. The second clamping portion (39) can abut a surface (50) on the collar (77).

The bracket (29) and mounting (76) allow the first pipe (36) to rotate around its longitudinal axis (Y). The bracket (29) and mounting (76) also limit the movement of the first pipe (36) so that it cannot move away from its longitudinal axis (Y).

To achieve a desired angle between the first and second pipes (36, 37) these are rotated around their longitudinal axes (X, Y). The inside faces (43,48) remain flat against each other. However the collar (77) allows the angle between the pipes (36, 37) to be changed.

This is best seen in Figures 6, 8, 11A and 11B where the longitudinal axis X is shown in two different orientations with respect to longitudinal axis Y. The second pipe (37) can outlay a cone centred at the longitudinal axis (Y). This allows the angle between the pipes (36, 37) to be varied through a large range to facilitate connecting the manhole (1) to sewer pipes at a variety of angles.

A second pair of rotational fasteners (51 A & 51 B) are used to secure the second clamping portion (39) to the main body (30). Tightening the fasteners (51 A & 5 B) causes the second clamping portion to squeeze the collar (77) to the main body (30) and thereby secure the mounting (76).

In addition, the pipes (36,37) are secured with respect to each other so that the angle between them is locked.

The first pipe's end (52) is connected to a sewer pipe (not shown) using techniques as should be known to one skilled in the art.

A bowl (53) is positioned above the manhole (1). The bowl (53) has an integral pipe (54) and a fluid pathway between the lowest point (55) in the bowl (53) and the integral pipe (54). A telescopic spacer (56) is used to support the bowl (53) within the manhole (1). The height is determined so that the integral pipe (54) can be connected to end (57) of the second pipe (37) in the bracket.

Spacers (58) have a bearing surface (59) and a clip end (60). The bearing surface (59) sits against the inside surface (61) of the cylinder shaped extension (4). The clip end (60) sits over the bowl's top edge (62). The spacers (58) are used to stabilise and prevent movement of, the bowl (53) within the manhole (1).

Multiple spacers (58) can be positioned around the perimeter of the bowl (53).

Guards (63) are positioned over top of the spacers (58). The guards (63) overlap the bowl's top edge (62) and prevent fluid getting between the bowl (53) and inside walls of the manhole (1 ).

A second aperture (64) can be made in the manhole (1) using techniques as known to those skilled in the art. The second aperture (64) should be above the lowest point in the bowl (53). The height of the second aperture (64) is determined according to the height of the sewer pipe (not shown) to be connected to the manhole (1).

A second bracket (65) is identical to first bracket (29).

The second bracket (65) is secured to the manhole (1) in a similar manner to that discussed above using a second clamping portion (66) and rotational fasteners (67A and 67B). The angle between the second bracket's first and second pipes (68, 69) is varied to achieve the desired angle between these. This occurs in a similar manner as for the first bracket (29) discussed above. The longitudinal axes of the pipes (68,69) are shown as (X2, Y2) respectively in Figures 9 and 10. The first pipe (68) is connected to a sewer pipe (not shown).

A wedge shaped section is cut from the bowl (53). The wedge shaped section is not visible in the drawings.

A transitional section (71 ) has a first portion (72) and a second portion (73). The first portion (72) is wedge shaped. This corresponds to the wedge shaped section cut from the bowl (53). The second portion (73) is configured to be connected to end (74) of the second brackets second pipe (69)

The first portion (72) is attached to the bowl (53) along the edges of the wedge shaped section. The second portion (73) is connected to end (74).

A ramp (75) is secured between the second portion (73), and the lowest point (55) in the bowl (53). The ramp (75) provides a pathway for fluid travelling through the sewer and manhole (1) in use. The ramp may help to ensure that fluid and suspended matter therein continue through the manhole (1).

It should be appreciated from the foregoing description that the present invention has a number of advantages. These include: · That the kitset provides improvements over the available prior art manholes;

• The kitset is compact and easy to transport due to the wall segments being able to nest together; and

• It is easier to provide connections between a manhole and a sewer at variable angles.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof.