Technical Field of the Invention

The present invention relates to a ducting assembly, in particular to a ducting assembly that can connect to another identical or substantially similar ducting assembly. Background to the Invention

Ducting assemblies can be used to house or carry an object such as a pipe, tube or cable, and separate it from the environment. For this purpose, they may be laid underground- underneath roads or railways, under bridges or inside tunnels. In particular, such ducting assemblies are useful in preventing contact between underground cables and the surrounding ground.

Due to commercial and manufacturing limitations, tubes and ducts are typically formed in sections of a specific length. These sections can be joined together on-site to form a system or network. Each section of duct is typically formed with a male part, or spigot, moulded on one end and a cooperating female part, or socket, moulded on the other end.

There are two conventional methods for joining sections of ducting together: the clip method and the push-fit method.

With the clip method, the spigot of a first section is inserted into the socket of a second section and one or more steel clips are secured over the join to hold the two sections in engagement. If required, a gasket can then be used to fill the space in between the cooperating spigot and socket to provide a watertight seal, therefore making the system impermeable. With the push- fit method, cooperating engagement formations are formed on the spigot and socket mouldings of each tube section. When the spigot of a first section is inserted into the socket of a second section, the engagement formation on the spigot of the first section automatically engages with the engagement formation on the socket of the second section to securely join the two sections together.

The push- fit method has the advantage that it is easier to join sections of ducting together. This is particularly useful where in situ access to the ducting system is difficult. However, the more cumbersome clip method is still widely used where a watertight system is required because a gasket cannot be used with ducts having conventional push- fit engagement formations. Thus, the conventional push- fit method suffers from the problem that it cannot be used to form an impermeable ducting system.

Embodiments of the present invention seek to address the above problems.

Summary of the Invention

According to a first aspect of the present invention, there is provided a ducting assembly comprising a body having a first end region with a first end portion, and a first engagement formation formed at the first end region for engaging with a corresponding engagement formation formed at an end region of another ducting assembly so as to connect the two ducting assemblies together at their end regions. The first engagement formation comprises a first push-fit coupling, and a gasket disposed between the first push-fit coupling and the first end portion.

In this way, the arrangement of the first push-fit coupling and the gasket allows for a ducting assembly to be easily and securely connected to another substantially similar or identical ducting assembly by using a push-fit mechanism, whilst also preventing fluids from entering or leaving the connected ducting assemblies though the join between them. Consequently, the present invention provides an improved watertight push-fit connection, which eliminates the typical requirement for using a steel clip, thus reducing the part count. Manufacturing costs are therefore reduced and assembly and installation times are shortened. In contrast, in known push- fit ducting arrangements, the push-fit coupling tends to be arranged very close to the end portion of the spigot, so there is insufficient space to provide a gasket between the coupling and the end portion.

The ducting assembly may have a substantially cylindrical, substantially rectangular or substantially square cross-section. Thus, the ducting assembly may be a cylindrical, rectangular or square tube. The internal area of the ducting assembly may be divided into compartments. These compartments may extend the whole length of the ducting assembly and they may all have an equal cross sectional area. The internal space of the ducting assemblies may be split up into 4, 6, 9, 12 or 15 compartments. The ducting assembly may have a length of around 1120 mm or 1070 mm. The body may further comprise a second end region with a second end portion located at the opposite end of the body to the first end region and first end portion.

The ducting assembly may further comprise a second engagement formation formed at the second end region for engaging with a corresponding engagement formation formed at an end region of another ducting assembly so as to connect the two ducting assemblies together at their end regions. The second engagement formation may incorporate any, all or no features of the first engagement formation.

The first engagement formation may comprise a male part or a spigot moulding that protrudes longitudinally from the ducting assembly. In this way, the spigot moulding is suitable for insertion into a corresponding part on another ducting assembly, such as a socket.

The second engagement formation may comprise a female part or a socket moulding. In this way, the socket moulding is suitable for receiving a corresponding part on another ducting assembly, such as a spigot.

Thus, the spigot moulding and socket moulding may be formed in a manner such that they are suitable for engagement with each other. In this way, two ducting assemblies according to the first aspect of the invention can be joined together by inserting the spigot of one ducting assembly into the socket of the other ducting assembly.

The second engagement formation may comprise a second push-fit coupling suitable for mating with the first push-fit coupling. In this way, two ducting assemblies according to the first aspect of the invention can be securely connected together in a push-fit manner by engaging the first push- fit coupling on the first ducting assembly with the second push- fit coupling on the second ducting assembly. Conversely, two ducting assemblies according to the first aspect of the invention can also be securely connected together in a push-fit manner by engaging the second push-fit coupling on the first ducting assembly with the first push-fit coupling on the second ducting assembly.

The first push-fit coupling may comprise one or more protrusions or lugs formed on the first engagement formation. More specifically, the one or more protrusions may be formed on the spigot moulding. The protrusions may be substantially cuboid shaped. The protrusions may have an inclined surface facing towards the gasket. In this way, the protrusions are oriented with their inclined surface towards the first end portion so that they can engage with the second push-fit coupling of another ducting assembly.

The second push- fit coupling may comprise one or more slots formed on or in the second engagement formation. More specifically, the one or more slots may be formed on the socket moulding. The slots may be substantially cuboid or rectangular shaped for receiving a substantially cuboid or rectangular shaped protrusion. The slots may be arranged in a series or in an array. The one or more slots may correspond to the one or more protrusions on the first engagement formation or the spigot moulding.

The gasket may be formed around the whole perimeter of the ducting assembly. The gasket may be substantially U-shaped. The base of the U may be oriented towards the centre of the ducting assembly. In this way, the gasket comprises two sealing surfaces arranged perpendicular to the ducting assembly, providing a greater surface area for contacting with the second engagement formation and thus providing an improved sealing arrangement. The gasket may be formed from rubber or a rubber material. In this way, the gasket is flexible so that it can deform when in contact with another part of the ducting assembly or a part of another ducting assembly.

In use, when two ducting assemblies are connected, the gasket may be provided out board of the lugs of the first engagement formation and in board of the slots of the second engagement formation. In this way, the gasket seals the connection between the two ducting assemblies such that fluid cannot flow into or out of the connected ducting assemblies via either push- fit coupling and in particular via the slots of the second push- fit coupling. The ducting assembly or any part thereof may be manufactured from nitrogen foamed high density polyethylene. Alternatively, the ducting assembly may be manufactured from high density polyethylene foamed by a chemical blowing agent. Alternatively, the ducting assembly may be manufactured from solid high density polyethylene. Alternatively, the ducting assembly may be manufactured from any other suitable thermoplastic material.

According to a second aspect of the present invention, there is provided a ducting system comprising two or more of the ducting assemblies of the first aspect of the invention connected together. The ducting system of the second aspect of the present invention may incorporate any or all features of the first aspect of the present invention as desired or as appropriate.

The ducting system may further comprise one or more clips for bracing the join between two ducting assemblies. The clip may be formed from steel.

According to a third aspect of the present invention, there is provided a ducting assembly substantially as described herein with reference to the accompanying drawings.

According to a fourth aspect of the present invention, there is provided a ducting system substantially as described herein with reference to the accompanying drawings.

Detailed Description of the Invention

In order that the invention may be more clearly understood an embodiment thereof will now be described, by way of example only, with reference to the accompanying drawings, of which: Figure 1 is a perspective view of a ducting assembly according to an embodiment of the invention;

Figure 2 is a cutaway perspective view of the first end region of the ducting assembly shown in Figure 1 ; the cutaway being at line A-A of Figure 1 ; Figure 3 is a cross section view of a first end region of the ducting assembly shown in Figures 1 and 2, and a second end region of another identical or substantially similar ducting assembly;

Figure 4a is a side view of a first step in a method for joining together the two ducting assemblies shown in Figure 3; Figure 4b is a side view of a second step in a method for joining together the two ducting assemblies shown in Figure 3;

Figure 5 is a cross section view of the first and second end regions shown in Figure

3 when connected together using the joining method shown in Figures 4a and 4b. Figure 6a is a perspective view of the first and second end regions shown in Figure

3; and

Figure 6b is a perspective view of the connected first and second end regions shown in Figure 5.

Referring to Figure 1, a first ducting assembly 1 comprises a tubular body 5 extending between a first end portion 6 and a second end portion 4. The first and second end portions 6, 4 define, respectively, a first end region 9 and a second end region 2 of the ducting assembly 1. The first ducting assembly 1 has a substantially square cross section that is divided up into four compartments 7 that also have substantially square cross sections. The four compartments 7 all have equal cross sectional areas. The substantially square first ducting assembly 1 therefore has four sides and thus edges of equal length. A first engagement formation is located at the first end region 9 and comprises a male or spigot moulding 8. A second engagement formation is located at the second end region 2 and comprises a female or socket moulding 3. The first and second engagement formations are formed around the full perimeter of the ducting assembly. The socket moulding 3 and spigot moulding 8 correspond to each other such that the socket moulding 3 can mate or engage with a spigot moulding on another identical or substantially similar ducting assembly, and the spigot moulding 8 can mate or engage with a socket moulding on another identical or substantially similar ducting assembly.

Referring to Figure 2, the first engagement formation further comprises a lip 12, a first push- fit coupling 11 and a gasket 10, provided on the spigot moulding 8. The lip 12 projects outwardly from the surface of the engagement formation.

The first push-fit coupling 11 comprises a series of substantially cuboid protrusions, or lugs, formed on, and projecting outwardly from, the outer surface of the first engagement formation.

The gasket 10 is substantially U-shaped and manufactured from rubber or a rubber material so that it is flexible. The gasket 10 is adhered to the outer surface of the first engagement formation such that the base of the U is oriented towards the centre to the ducting assembly 1. These features of the first engagement formation are arranged such that the gasket 10 is positioned between the first end portion 6 and the first push- fit coupling 11.

Referring to Figure 3, a first ducting assembly 1 is positioned adjacent a second ducting assembly 21. The first ducting assembly is described above with reference to Figures 1 and 2. The second ducting assembly 21 has features that are identical to the first ducting assembly 1.

The second engagement formation comprises a second push- fit coupling 211 located at the second end region 22 that can mate with the first push- fit coupling 11 on the first engagement formation. In this embodiment, the second push- fit coupling 211 comprises a series of slots or windows that are formed in the socket moulding 23 for mating and engaging with the protrusions of the first push- fit coupling 11.

Referring to Figures 4a and 4b, to connect the first ducting assembly 1 to the second ducting assembly 21, the spigot moulding 8 on the first ducting assembly 1 is inserted at an angle to the horizontal into the socket moulding 23 on the second ducting assembly 21 until an edge of the spigot moulding 8 of the first ducting assembly 1 abuts with second ducting assembly 21. Thus, the edge of the spigot moulding 8 slides over a corresponding edge of the socket moulding 23 so that the spigot moulding 8 and socket moulding 23 overlap each other.

Minor adjustments to the position of the first ducting assembly 1 are then made so that the protrusions of the first push-fit coupling 1 1 on the abutted edge of the spigot moulding 8 align with the corresponding slots of the second push- fit coupling 211 on the socket moulding 23. Whilst keeping the spigot moulding 8 in abutment with second ducting assembly 21, the first ducting assembly 1 is lowered so as to align the first and second ducting assemblies 1, 21 in a horizontal orientation. This inserts the remaining edges of the spigot moulding 8 of the first ducting assembly 1 into the socket moulding 23 of the second ducting assembly 21. Thus, the protrusions of the first push- fit coupling 11 become aligned with, and engaged with, the slots of the second push- fit coupling 211. The spigot moulding 8 and socket moulding 23 now fully overlap each other.

Consequently, the first and second ducting assemblies 1, 21 have now been connected together at their end regions by using a push-fit mechanism. A clip may be secured to the first and second ducting assemblies 1, 21 to bridge the join between them in order to increase the force required to break them apart.

Referring to Figure 5, the spigot moulding 8 of the first ducting assembly 1 is shown fully mated with the socket moulding 23 of the second ducting assembly 21, thus engaging the corresponding push- fit couplings 11, 211 and securely connecting the two ducting assemblies together.

As can be seen, the engagement of the first push-fit coupling 11 with the second push-fit coupling 211 deforms the flexible gasket 10 so that the space between the spigot moulding 8 of the first ducting assembly 1 and the socket moulding 23 of the second ducting assembly 21 in board of the slots is substantially filled by the gasket 10. The gasket 10 therefore acts as a seal between the connected ducting assemblies 1, 21 to prevent any leakage at the join.

Referring to Figures 6a and 6b, the first end region 9 of the first ducting assembly 1 is shown adjacent in Figure 6a, and engaged with in Figure 6b, the second end region 9 of the second ducting assembly 21. The lugs of the first push- fit coupling 11 are positioned so as to leave space on the first engagement formation for a gasket 10 to be provided out board of the first push- fit coupling 11. The slots of the second push-fit coupling 211 are correspondingly positioned so that when the first ducting assembly 1 is connected to the second ducting assembly 21, the gasket 10 is provided in board of the slots. Thus, the first push- fit coupling 11 and second push- fit coupling 211 are positioned such that the gasket 10 seals the connection between the first ducting assembly 1 and the second ducting assembly 21.

The above embodiment is described by way of example only. Many variations are possible without departing from the scope of the invention.