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Title:
A KIT OF PARTS FOR CLAMPING A POLE
Document Type and Number:
WIPO Patent Application WO/2024/047105
Kind Code:
A1
Abstract:
A kit of parts (100) for supporting and clamping a pole comprising a clamping device (1), an extension member (4) and a ground engaging socket (2), the ground engaging socket (2) having means to clamp a pole in position and having a proximal end (3) for location at ground level and a distal end (5) for location beneath the ground, wherein the clamping device (1) comprises at least two clamping mechanisms, which in use, align and clamp the socket (2) and extension member (4) together in a configuration whereby a portion of the proximal end (15) of the extension member (4) is accommodated within the socket (2).

Inventors:
GOGARTY FRANK (IE)
MCGEOUGH STEPHEN (IE)
Application Number:
PCT/EP2023/073784
Publication Date:
March 07, 2024
Filing Date:
August 30, 2023
Export Citation:
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Assignee:
NAL PRODUCTS LTD (IE)
International Classes:
E04H12/22; A63B71/02; E01F9/685
Domestic Patent References:
WO2016110703A12016-07-14
WO2007135119A12007-11-29
WO2007135119A12007-11-29
Foreign References:
GB2254349A1992-10-07
DE19936694C12000-11-30
Attorney, Agent or Firm:
SLINGSBY PARTNERS LLP (GB)
Download PDF:
Claims:
CLAIMS:

1 . A system for supporting and clamping a pole comprising: a ground engaging socket having means to clamp a pole in position and having a proximal end for location at ground level and a distal end for location beneath ground level comprising a flange with an inner recess; an extension member and a clamping device comprising at least two clamping mechanisms, each clamping mechanism comprising a member for interaction with a ribbed exterior of a proximal end of the extension member; wherein a portion of the proximal end of the extension member is aligned with and projected into the inner recess of the socket when the clamping device interacts with the extension member.

2. The system of claim 1 , further comprising a base member for location at a distal end of the extension member.

3. The system of claim 2, wherein the base member comprises an inner recess and is connected to a distal end of the extension member with a second clamping device.

4. The system of any preceding claim wherein the depth of the inner recess is in the range of 95% to 110% the length of a trough of the extension member.

5. The system of any preceding claim, wherein the member for interaction with the ribbed exterior of the proximal end of the extension member comprises at least one elongate ridge which extends from an inner circumferential edge of the clamping device.

6. The system of claim 5, wherein a section of an inner surface of the elongate ridge is tapered.

7. The system of any preceding claim, wherein the at least two clamping mechanisms comprise half shells, which are configured to be bolted or hinged together in order to form a ring like structure.

8. The system of any of claims 1 to 6, wherein the at least two clamping mechanisms are clamping units, which in use, are bolted directly through bolt holes in the flange of the socket.

9. The system of claim 8, wherein, in use, the clamping units are equally spaced about the perimeter of the extension member.

10. The system of any preceding claim, wherein the extension member is a twin walled Pipe.

11 . The system of any preceding claim, wherein the means to clamp a pole comprises a clamping bolt which can be actuated to advance a distal end of the clamping bolt into the socket and towards the pole, and a pressure distribution bolt cap, locatable on the distal end of the clamping bolt which is freely rotatable with respect to the clamping bolt, the pressure distribution bolt cap having a distal surface whose area is greater than that of the distal end of the clamping bolt.

12. The system of any preceding claim, wherein a side section of a rib of the ribbed exterior of the extension member is tapered.

13. The system of any of the preceding claims, in which the ground engaging socket is a one-piece casting of ductile iron or similar material.

14. A kit of parts for supporting and clamping a pole comprising a clamping device, an extension member and a ground engaging socket, the ground engaging socket having means to clamp a pole in position and having a proximal end for location at ground level and a distal end for location beneath ground level comprising a flange, wherein the clamping device comprises at least two clamping mechanisms, each clamping mechanism comprising a member for interaction with a ribbed exterior of a proximal end of the extension member such that, in use, the clamping device aligns and clamps the socket and extension member together in a configuration whereby a portion of the proximal end of the extension member is accommodated within an inner recess of the socket and wherein the inner recess is located within the flange.

Description:
A KIT OF PARTS FOR CLAMPING A POLE

Field of the Invention

This invention relates to devices, systems and kits of parts for supporting poles such as road traffic signs, lighting columns etc., and has particular application in supporting poles through use of a clamping device which connects a longitudinal stabilisation extension member to a socket which retains the pole. In particular, it relates to a kit comprising a ground engaging socket with an upper clamping section and preferably a base member with a lower clamping section, with an extension member being clamped to the ground engaging socket and, if present, the base member.

Background of the Invention

A device for supporting a pole typically comprises a ground engaging socket housing for mounting in the ground, having a proximal end with an opening for receiving one end of the pole such that the opening is more or less flush with the surface of the ground and having a distal end with an opening for receiving a proximal end of an extension member in order to generate a required installation depth. Preferably, a base member engages with a distal end of the extension member.

During vehicular impact the pole swells and moves. The large force generated by the movement of the pole acts to try to cause the socket and foundation system to move.

The inclusion of an extension member ensures that the socket is supported and lends extra strength to the system. The interface between the socket and the extension member is thus critical as is represents a potential area for misalignment during installation and stress concentration during vehicular impact.

The base member assists in locating and supporting the base of the inserted pole and, in use, is fully submerged below the ground. The base member may incorporate additional features which support a drainage function, cable routing etc. Although perfect alignment between base member and the extension tube is preferred, minor misalignment in this interface is not typically a critical issue in use. The extension member is typically a tubular member which is fabricated from steel or plastic. Typically, the extension member and the socket are connected together with flanges or material specific connectors or welded together. The ground engaging socket (hereafter referred to as socket) is metal, however, the extension member could be metal or plastic. A metal to plastic interface can be particularly technically complex due to a difference in material strength between the two materials and other divergent material properties such as sensitivity to heat etc.

An additional issue has been identified in the prior art in the alignment of the socket and the extension member. As the extension member and the socket must be axially aligned, care must be taken when cutting the end of the extension member which interacts with the socket as an uneven cut could cause the extension member to be connected at an angle of greater than 0° to the longitudinal axis of the distal end of the socket. If the extension member is connected to the socket at an angle greater than 0° to the socket, then the extension member is not directly in line with the socket and it is thus more susceptible to stress build up and potential failure.

Avoiding damage to the surface of the pole below ground is a particular concern. Poles are designated for a service life of several years. This service life is based on the assumption that the pole is undamaged, and that the installation design is unchanged throughout the life of the device.

Patent Application W02007135119 discloses a retention system for a pole comprising a socket, a ribbed extension unit and a base unit. The extension unit is made from a relatively weak material and the extension unit cannot withstand the potential force to which is it exposed, so an additional structural reinforcement is required (which is provided by means of a series of bars which are positioned around the exterior of the extension unit). In addition, the socket itself is provided in two halves, known as a split casing. Split casing causes many issues in terms of alignment of casts, time to assemble, weight of socket and generation of areas of stress concentration.

It is thus beneficial to improve the prior art in order to create an improved socket which is more user friendly, less subject to human error and more economically effective.

There is provided a system for supporting and clamping a pole comprising; a ground engaging socket having means to clamp a pole in position and having a proximal end for location at ground level and a distal end for location beneath ground level comprising a flange with an inner recess, an extension member and a clamping device comprising at least two clamping mechanisms, each clamping mechanism comprising a member for interaction with a ribbed exterior of a proximal end of the extension member; wherein a portion of the proximal end of the extension member is aligned with and projected into the inner recess of the socket when the clamping device interacts with the extension member.

There is further provided a kit of parts comprising a clamping device, an extension member, a ground engaging socket having a proximal end for location at ground level and a distal end for location beneath the ground, wherein the distal end comprises a flange and wherein the clamping device comprises at least two clamping mechanisms, each clamping mechanism comprising a member for interaction with a ribbed exterior of a proximal end of the extension member such that, in use, the clamping device aligns and clamps the socket and extension member together in a configuration whereby a portion of the proximal end of the extension member is accommodated within an inner recess of the socket, the inner recess being located within the flange.

The following statements may apply to both the system and the kit of parts.

In the preferred embodiment, the system or kit may also comprise a base member for location at a distal end of the extension member, such that, in use, the distal end of the extension member is connected to the base member.

Preferably, the ground engaging socket is a one-piece casting of ductile iron or similar material.

Preferably, the base member comprises an inner recess.

Preferably the depth of the inner recess is in the range of 95% to 110% the length of a trough of the extension member.

Preferably, the base member is connected to the extension member with a second clamping device. Preferably, the at least two clamping mechanisms comprise half shells, which are configured to be bolted or hinged together in order to form a ring like structure.

According to an alternative example of the present invention, the at least two clamping mechanisms are clamping units, which in use, are bolted directly through bolt holes in the flange of the socket. Preferably, in use, the clamping units are equally spaced about a perimeter of the extension member.

Preferably, the extension member is a twin walled pipe.

Preferably, the member for interaction with the ribbed exterior of the proximal end of the extension member comprises at least one elongate ridge which extends from an inner circumferential edge of the clamping device.

Preferably, a section of the inner surface of the elongated ridge is tapered.

Preferably, a side section of a rib of the ribbed exterior of the extension member is tapered. Preferably, the member of the system for interaction with the ribbed exterior of the proximal end of the extension member comprises at least one elongate ridge which extends from an inner circumferential edge of the clamping device.

Preferably, a section of the inner surface of the elongate ridge of the system is tapered.

Preferably, a side section of a rib of the ribbed exterior of the extension member of the system is tapered.

Brief Description of the Drawings

Further details of the invention will be apparent from the following description of embodiments thereof, given by way of example only, with reference to the accompanying drawings, in which:

Figure 1a is a perspective view of the prior art, wherein an extension member is fitted to a socket through means of grub screws and the extension member is fitted to a base member;

Figure 1b is an exploded perspective view of Figure 1a;

Figure 2 is a side view of an alternative piece of prior art, wherein an extension member is incorporated in production to a socket; Figure 3 is a side section illustrating a socket, extension member, base member and clamping device in accordance with an embodiment of the present invention;

Figure 4 is a magnified view of an area circled in Figure 3, which illustrates the interface between the socket, the extension member and the clamping device of the present invention;

Figure 5a is a side elevation view of the first embodiment of the present invention;

Figure 5b is a cross sectional plan view (along line AJ in Figure 5a) which illustrates a half shell of the clamping device of the first embodiment of the present invention;

Figure 5c is a cross sectional elevation view (along line AG in Figure 5a) which illustrates a half shell of the clamping device of the first embodiment of the present invention;

Figure 5d is two cross sectional elevation views (along lines Al and AH which are shown in Figure 5a) of the half shell of the clamping device of the first embodiment of the present invention;

Figure 6 is a cross sectional view of the first embodiment of the invention which illustrates an angle of the tapered inner surface of an elongated ridge of the clamping device;

Figure 7 is a cross sectional view of the second embodiment of the invention which illustrates an angle of the tapered inner surface of the elongated ridge of the clamping device;

Figure 8a is a perspective view of a clamping bolt, nut and pressure distribution bolt cap according to the present invention;

Figure 8b is an exploded view of the clamping bolt, nut and pressure distribution bolt cap of Figure 8a;

Figure 9 is a perspective view of a socket and the clamping bolt, nut and pressure distribution bolt cap of Figure 8a;

Figure 10 is a cross sectional view of a clamping bolt, nut and pressure distribution bolt cap in use according to the present invention; Figure 11a is a side elevation view of a half shell of an alternative first embodiment of the present invention comprising a plurality of hinged segments;

Figure 11 b is a cross sectional elevation view (along line BB in Figure 11a) which illustrates a plurality of connected segments;

Figure 11c is a cross sectional elevation view (along line CC in Figure 11a) which illustrates a plurality of connected segments in use to form a ring like structure;

Figure 12a is a side elevation view of a half shell of an alternative first embodiment of the present invention comprising a hinge and a bolt in use;

Figure 12b is a cross sectional elevation view (along line BB in Figure 12a) which illustrates two half shells connected in use through a bolt and a hinge;

Figure 12c is a cross sectional elevation view (along line CC in Figure 12a) which illustrates two half shells connected in use through a bolt and a hinge, to form a ring like structure;

Figure 13 is a perspective view of a socket, extension member and clamping device according to a second embodiment of the present invention, wherein several independent clamping mechanisms are provided;

Figure 14 is a side view of a socket, extension member and clamping devices according to a second embodiment of the invention;

Figure 15 is a cross sectional elevation view of a socket, extension member and clamping device according to a second embodiment of the present invention;

Figure 16a is a magnified view of an area circled in Figure 15 and which illustrates the interface between the socket, extension member and the clamping device according to a second embodiment of the present invention;

Figure 16b is an exploded view of the items of Figure 16a;

Figure 17 is a perspective view of part of a clamping device of the second embodiment of the present invention; Figure 18a is a plan view of part of the clamping device of the second embodiment of the present invention;

Figure 18b is a side elevation view of the part of the clamping device of Figure 18a;

Figure 18c is a plan view of a part of the clamping device of Figure 18a wherein a bolt has been included;

Figure 18d is a cross sectional elevation view of part of the clamping device which is shown in Figure 18a; and

Figure 19 is a perspective view of an embodiment according to the present invention where a clamping device is in use between a socket and a proximal end of an extension member and again between a base member and a distal end of the extension member.

Detailed Description

There is provided a kit of parts 100 for clamping a socket 2 to an extension member 4 such that a proximal end 15 of the extension member 4 is held in secure contact with the socket 2. In the preferred embodiment, there is further provided a base member 7. In use, a distal end 17 of the extension member 4 is held in secure contact with the base member 7. The socket 2 is a one-piece casting made of ductile iron.

As shown in Figure 3, the kit 100 comprises; a clamping device 1 , an extension member 4, and a socket 2. The extension member 4 is typically a rigid double walled plastic pipe (also known by the skilled person as a twin walled tube, a double walled pipe or a double walled tube). The standard design and manufacturing process of the plastic pipe means that the plastic pipe is ribbed (wherein the outer surface of the plastic pipe comprises parallel circular upstanding bands or ribs 6 which are equally spaced apart). These ribs 6 may also be known as corrugations and the pipe may be known as a corrugated pipe. The ribs 6 define a peak 8 and trough 10 style of geometry on the outside of the plastic pipe as shown in Figures 3, 4, 6, 7, 13, 14, 15, 16a 16b and 19.

As shown in Figure 3, there is also provided at least one clamping bolt 32 and at least one corresponding pressure distribution bolt cap 34. A proximal end of the socket 2 comprises a pole receiving chamber into which a pole can be received. The at least one clamping bolt 32 comprises a head and a shaft carrying a threaded section. The at least one clamping bolt 32 is actuated to advance the distal end of the clamping bolt 32 through a hole 36 in the socket 36 towards the pole and into the pole receiving chamber. At least one clamping bolt 32 with a corresponding pressure distribution bolt cap 34 is used to support the pole in the pole receiving chamber. Preferably at least two clamping bolts 32 with corresponding pressure distribution bolt caps 34 are used to support the pole in the pole receiving chamber. Each clamping bolt 32 is threaded and provided with a corresponding nut 30. In use, the nut 30 is received in a hexagonal hole so that rotation of the nut 30 is prevented. The pressure distribution bolt cap 34 is mounted on the distal end of the clamping bolt and is freely rotatable with respect to the clamping bolt 32. The pressure distribution bolt cap 34 is in the form of a cylindrical or hexagonal cup with a cylindrical sidewall projecting from a base wall, wherein the cylindrical sidewall defines an internal space into which the distal end of the clamping bolt 32 is received, and wherein the base wall has a flat or contoured external surface which provides an outer terminal contact surface for contacting the pole. It will be appreciated that pressure distribution bolt cap 34 outer terminal contact surface shapes may be round, hexagonal or otherwise without departing from the inventive concept of the invention. The area of an outer terminal contact surface of the pressure distribution bolt cap 34 is greater than the area of the distal end surface of the clamping bolt 32. The pressure distribution bolt cap 34 distributes the high pressure generated by the clamping bolt 32 when it has been activated to clamp a pole within the pole receiving chamber. The pressure distribution bolt cap 34 protects the pole by providing a flat and stationary surface for interaction with the pole when the pole is clamped in place by the clamping bolt 32. This design allows high force clamping without damage to the pole, the clamping bolt 32 or the pressure distribution bolt cap 34, allowing repeat use of the pole housing throughout the life of the pole without the need of a protective sleeve or insert.

Each pressure distribution bolt cap 34 is fixed onto the distal end of the clamping bolt 32 by a locating means comprising complementary interference fit geometries on the clamping bolt 32 and the pressure distribution bolt cap 34 such that the distal end of the clamping bolt 32 is engaged with the pressure distribution bolt cap 34, and in particular such that a circular groove on the inner surface of a cylindrical sidewall of the pressure distribution bolt cap 34 also is engaged with a complementary recessed groove on the surface of the distal end of the clamping bolt 32. In this way, the pressure distribution bolt cap 34 is held in position by a locating means 40 on the pressure distribution bolt cap 34 and a complementary locating means 42 on the clamping bolt 32 so that rotation of the pressure distribution bolt cap 34 relative to the clamping bolt 32 is permitted. The two locating means 40, 42 are sized so that they effect an interference fit with each other. Preferably, the interference fit shall be such that the pressure distribution bolt cap 34 can be pressed onto the clamping bolt 32 with modest force. Further preferably, the pressure distribution bolt cap 34 shall be removable from the clamping bolt 32 with modest force by unscrewing the clamping bolt 32. In this context a modest force shall be considered to be a force within the range of 5-20Nm torque.

As the pressure distribution bolt cap 34 protects the pole and any coating on the pole, it is no longer necessary to insert a protective sleeve between the pole and the clamping bolt. The pressure distribution bolt cap 34 also transmits very high clamping pressure thus keeping the pole in place, whilst still protecting the pole (or the pole coating, if a coating is present) from damage.

The pressure distribution bolt cap 34 also supports the end of the clamping bolt 32 within the socket 2 in such a way that damaging forces applied to the clamping bolt 32 during vehicular impact and torsion due to wind loads are eliminated. This is achieved by the distal end of the clamping bolt 32 being constrained against lateral movement by merit of its position, in use, within the pressure distribution bolt cap 34. The pressure distribution bolt cap 34 is in turn constrained in a hexagonal hole in the socket 2 which also houses a nut 30 wherein the pressure distribution bolt cap 34 fits into the hexagonal hole but remains free to rotate. In use, the shape of the pressure distribution bolt cap 34 allows the pressure distribution bolt cap 34 to be used as a ‘guide’ for the clamping bolt 32 when the clamping bolt 32 is located in and moves along a guide channel in the socket 2.

In the prior art, as shown in Figures 1a, 1b and 2, the extension member 4 is typically a metal pipe which can be connected directly to the socket 2 using readily available material specific connectors, as the socket 2 is also made of metal. Plastic extension members 4, however, cannot be readily connected or aligned directly to metal due a number of technical issues including differences in material properties between metal and plastic, including but not limited to material strength and material resistance to temperature.

The socket 2 comprises, at its distal end 5, an opening 11 for receiving the proximal end 15 of the extension member 4. The opening 11 on the distal end 5 of the socket 4 comprises a flange or a lip 12 such that the clamping device 1 can be clamped over the lip 12. The lip 12 comprises a longitudinal part 14 which comprises an inner recess 16. The inner recess 16 has a depth of at least 95% the length of one trough 10. Preferably the inner recess 16 has a depth which is 110% the length of the trough 10 of the extension member 4, such that, in use, the proximal end 15 of the extension member 4 sits within the inner recess 16 of the socket 2. The inner recess 16 is sized such that the accuracy of a cut of the extension member 4 becomes immaterial, provided that the cut is contained within one trough 10 of the extension member 4. In use, the extension member 4 must be positioned such that its longitudinal axis is at 90 degrees to the plane of the top surface the proximal end 3 of the socket 2. As the plane of the top surface of the proximal end 3 of the socket 2 lies at 90 degrees to the longitudinal axis of opening 11 of the distal end of the socket 2, the longitudinal axis of the extension member 4 is therefore also fixed so that it is in line with the longitudinal axis of the opening 11 for receiving the socket 2.

The clamping device 1 is designed to grip the ribs 6 and press the proximal end 15 of the extension member 4 firmly into the inner recess 16 in the distal end 5 of the socket 2. The inner recess 16 is designed to receive the proximal end 15 of the extension member 4, and in particular, provides a matching mating surface to accommodate the outermost trough 10 on the proximal end 15 of the extension member 4. The amount of the proximal end 15 of the extension member 4 which sits within the inner recess 16 may be variable such that, as previously noted, the cut of the extension member 4 does not need to be exactly in line or parallel with the adjacent rib 6. The clamping device 1 is configured such that the inner recess 16 of the socket 2 is at least the length of one trough 10 of the extension member 4. Any imperfections that might arise from cutting the extension member 4 can be absorbed in the inner recess 16 without affecting the overall clamping ability of the clamping device 1 . This means that, for example, an extension member 4 cut which results in a longer length of trough 10 on one circumferential location and a shorter length of trough 10 on another circumferential location of the same trough 10 can be accommodated by the inner recess 16 of the socket 2 without causing any difference in the overall effect of the clamping device 1 when compared with an extension member 4 with a cut which is exactly parallel to the adjacent rib 6.

The inner recess 16 ensures that the clamping device 1 holds the extension member 4 firmly at 90 degrees to the top surface of the socket 2. The clamping pressure is in a vertical plane, which is in line (or parallel) with the longitudinal axis of the opening 11 at the distal end 5 of the socket 2. The clamping pressure is achieved though different styles of clamping devices 1 which share the same inventive concept and which act directly or indirectly to apply the clamping pressure depending on the size of socket 4.

The clamping device 1 comprises at least two clamping mechanisms. As shown in Figures 5a, 5b, 5c and 5d, in a first embodiment the clamping device 1 comprises two half shells which can be bolted or hinged, or bolted and hinged, together about both the distal end 5 of the socket 2 and the proximal end 15 of the extension member 4 concurrently. The outermost circumferential edges of each of the half shell extends out to form an elongated ridge 24. In use, one elongated ridge 24 sits over the flange or lip 12 of the socket 2 and the other elongated ridge 24 sits inside a trough 10 of the extension member 4 such that the adjacent peak 8 of the extension member 4 is trapped inside the half shell. In the preferred embodiment, a section of the inner surface 9 of each of the elongated ridges 24 is tapered in order to accommodate the outer shape of a portion of the ribs 6 of the extension member 4, with which, in use, they share an interface. The tapered nature of the inner surface 9 of each of the elongated ridges 24 provides a wedge like structure, which interacts with the peak of the extension member 4 such that, the extension member 4 is pushed up into the socket as the clamp is tightened together. The axial force exerted on the extension member 4 by the clamping device 1 acts through the contact point of the peak 8 of the extension member 4 and the section of the tapered inner surface 9 of the elongated ridge of the clamping device 1. As the clamping device 1 is tightened about the extension member 4, the contact point moves along the section of the tapered inner surface 9 of the elongated ridge 24, thus forcing the extension member 4 upwards towards the socket 2 as it travels along the section of the tapered inner surface 9 of the elongated ridge 24. As shown in Figure 6, in the first embodiment, the angle A between the tapered inner surface 9 of the elongated ridge 24 with respect to a horizontal plane in use, is in the range of 10° to 30°, preferably, the angle of the taper is 15°. It will be appreciated that the horizontal plane in use is equal to a plane perpendicular to the axial plane of the extension member 4. In use, as the half shells are tightened together, the tapered inner surfaces 9 of the elongated ridges 24 of the half shells provide an axial clamping force in a wedge like action. Thus, both the proximal end 15 of the extension member 4 and the distal end 5 of the socket 2 are trapped within the half shells. In an alternative embodiment, the sides of the ribs 6 of the extension member 4 comprises tapered sections. In a further embodiment, both the sides of the ribs 6 of the extension member 4 and the inner surfaces 9 of the elongated ridges 24 of the clamping mechanisms comprise tapered sections. In use, when the half shells have been correctly mounted, the clamping mechanisms form a circumferential structure (also known as a ring like structure) about both the proximal end 15 of the extension member 4 and the distal end 5 of the socket 2. In the preferred first embodiment, the at least two half shells comprise a bolt hole 20 at each end of each half shell such that each set of half shells can be joined at either end by at least one bolt at either end (thus at least two bolts 18 with at least two corresponding nuts 22 over the full clamping device 1). In an alternative connection style of the first embodiment, as shown in Figure 7a, 7b and 7c, the two half shells may be joined with a hinge at one end and a bolt at the other end. The hinged set of half shells can be joined together by at least one bolt and one nut. As shown in Figure 6a, 6b and 6c, it will also be appreciated that each half shell may be made up of segments. Some or all of the segments may be identical. The segments may be connected together with hinged connections in order to form a complete half shell or full round structure.

As shown in Figures 13, 14, 15, 16a, 16b, 17, 18 and 19 the clamping device 1 of the second embodiment of the invention comprises at least two, most preferably three, clamping mechanisms, wherein each clamping mechanism is a clamping unit. Each clamping unit has a curved inner surface 28 with an angle of curvature which corresponds to a portion of the angle of curvature of the outside of the extension member 4. The clamping unit comprises a wall section with a bolt hole 20 and an elongated ridge 24 which protrudes directly from the curved inner surface 28 of the wall section. In use, the elongated ridge 24 rests in a trough 10 of the proximal end 15 of the extension member 4 such that the elongated ridge 24 is in contact with the outermost adjacent peak 8 on the proximal end 15 of the extension member 4. A section of the inner surface 9 of the elongated ridge 24 is tapered. As shown in Figure 13, 14, 15, 16a, 16b and 19 the second embodiment of the invention is used in conjunction with a socket 2 having a flange 12 at its distal end 5, wherein the flange 12 comprises a series of bolt holes 26. Each clamping unit is attached to the flange 12 through use of a bolt 18 and nut 22. The tapered nature of the inner surface 9 of the elongated ridge 24 provides a wedge like structure, which interacts with the peak of the extension member 4 such that, the extension member 4 is pushed up into the socket as each of the clamping mechanisms is tightened to the flange 12. In use, it is important that each of the clamping mechanisms are loosely fixed and then tightened in stages. Tightening one clamping mechanism fully, while the other clamping mechanisms are not engaged could cause an alignment imbalance. The axial force exerted on the extension member 4 by the clamping mechanism acts through the contact point of the peak 8 of the extension member 4 and the tapered inner surface 9 of the elongated ridge 24 of the clamping mechanism. As the clamping mechanism is tightened to the flange 12, the contact point moves along the section of the tapered inner surface 9 of the elongated ridge 24 of the clamping mechanism, thus forcing the extension member 4 upwards towards the socket 2 as it travels along the section of the tapered inner surface 9 of the elongated ridge 24 of the clamping mechanism. In use, the angle A between the tapered inner surface 9 of the clamping mechanism with respect to a horizontal plane, as illustrated in Figure 7 is in the range of 10° to 30°, preferably, the angle A is 15°. It will be appreciated that the horizontal plane in use is equal to a plane perpendicular to the axial plane of the extension member. In use, the tightening action of the bolt 18 and nut 22 presses the flange 12 and adjacent rib 6 of the proximal end 15 of the extension member 4 towards each other until a side of the adjacent rib 6 is in contact with the socket 2. The cut line of the proximal end 15 of the extension member 4 does not affect the use of the clamping device 1 as the proximal end 15 of the extension member 4 through which a cut is made fits inside an inner recess 16 of the socket 2. The ribs 6 are consistent throughout the extension member 4 in terms of size and spacing and thus the cut line does not need to be consistent provided that the cut is limited to one trough 10. In the second embodiment, the preferred configuration comprises at least two, preferably three, clamping units which are evenly spaced about the circumference of the extension member 4. It will be appreciated that more clamping units could also be used to enable the same effect (for example four clamping units, five clamping units or six clamping units).

Preferably, the distal end 17 of the extension member 4 is located and engaged with the base member 7 using a simple male-female connection. Typically, the base member 7 comprises internal ribs which correlate to the external ribs of the extension member 4. Thus, in use, when a portion of the distal end 17 of the extension member 4 is located within the base member 7, at least one peak 8 of the extension member 4 engages with a trough 10 of the base member 7. The base member 7 is typically formed from two parts which are bolted together about the distal end 17 of the extension member 4. The joint between the extension member 4 and the base member 7 does not need to be precisely aligned or extremely rigid and a certain amount of relative movement between the extension member 4 and the base section 7 is possible without affecting the overall performance of the kit 100. In a further embodiment (shown in Figure 19) an adapted base member 7 (comprising a flange 12, longitudinal part 14 of flange 12, inner recess 16 of flange etc. or a flange comprising bolt holes 12) may be connected to the extension member 4 through use of a second clamping device 1.

The base member 7 may take a variety of different forms depending on its primary use or location, for example a base member 7 may be a bend section (also known as duckfoot) as shown in Figure 3, a flat base as shown in Figure 1a and 1b, a T-shaped base or a multiport base etc. The base member 7 may additionally serve as a drainage feature or a cable conduit. The kit of parts 100 connects the body of the socket 2 to a section of extension member 4 with a clamping device 1 , such that the extension member (4) can be cut to different lengths to generate different installation depths of finished sockets 2.

It is to be understood that the invention is not limited to the specific details described herein which are given by way of example only, and that various modifications and alterations are possible without departing from the scope of the invention as defined in the claims.