GB2577923A

GB2577923A - Structural assembly

Info

Publication number: GB2577923A
Application number: GB1816570.4A
Authority: GB
Inventors: John Serjeant Christopher
Original assignee: Individual
Current assignee: Christopher John Serjeant; PETER ANTHONY ASHFORD
Priority date: 2018-10-11
Filing date: 2018-10-11
Publication date: 2020-04-15
Anticipated expiration: 2038-10-11
Also published as: GB201816570D0; EP3636858A1; GB2577923B

Abstract

The assembly includes elongate sleeve sections 20 having a tubular wall 21 defining a duct 22, and flanges 23 extending outwardly from the tubular wall along its length defining channels 24. The assembly includes a core section (40, Fig. 5) receivable withinthe duct, and cover strips (30, Fig. 4) for engagement between adjacent flanges 23 to close the channels 24. The sections may be used to assemble upright pole members of a mast, having spacing bars 8, bracing bars 9 and brackets 10 (see Fig. 1) for supporting antenna and communication units. The parts may be extruded aluminum sections to provide a lightweight mast suitable for installation on top of buildings. There may be a plurality of short core sections used to join a plurality of longer sleeve section end-to-end, being secured together via bolt holes 28. The covers may snap fittingly engage the flanges via barbed hooks, and may be convex such that the poles formed may have a circular outer profiles.

Description

STRUCTURAL ASSEMBLY

TECHNICAL FIELD OF THE INVENTION

This invention relates to structural assemblies as used, for example, in the construction of mobile phone masts.

BACKGROUND

Structural assemblies such as mobile phone masts, antenna supports, lighting columns, display systems and water towers are often formed of galvanised steel. Whilst such structures are strong and durable they are also heavy and expensive, and they are not easily adaptable to achieve different configurations. In many situations, for example when a mobile phone mast is to be mounted on top of a building, the assembly needs to be lightweight to avoid over-loading the structure beneath. There may also be other important considerations: the structure may need to be visually unobtrusive; on exposed sites it needs to be capable of withstanding high winds; in many situations there is a need to protect cables which run up the mast, but the cables also need to be easily accessible for maintenance purposes. -2 -

FR 2 473 094-Al discloses a tapered tubular support which may be used as a mast or a street lighting column. The support is formed from elongate strip-shaped parts which each have a curved outer wall with longitudinal grooves formed in its opposite edges. A web extends radially inwards from the middle of the curved wall. The strip-shaped parts are connected by bracing elements which progressively increase in size along the support causing the spacing between the parts to increase along the support, forming a perforated structure of tapered shape. The bracing elements have arms which extend radially outwards from a central portion and which each carry two lugs forming a groove for receiving a web of a strip-shaped part. The open frame is covered by inserting cover elements in the grooves presented by the edges of the curved walls.

SUMMARY OF THE INVENTION

When viewed from one aspect the present invention proposes a structural assembly: - an elongate sleeve section (20) having - a tubular wall (21) defining a duct (22), and - a plurality of flanges (23) extending outwardly from the tubular wall along the length thereof to define a plurality of channels (24); - a core section (40) receivable within the duct (22) of the elongate sleeve section; - cover strips (30) for engagement between adjacent flanges (23) -3 -of the elongate sleeve section to close the channels (24).

In an embodiment a plurality of elongate sleeve sections may be arranged end-to-end and connected together by one or more core sections.

In an embodiment there are aligned holes in the sleeve sections and the core sections to receive bolts or other fastening elements. The holes are preferably formed in the tubular wall of the sleeve sections and within the channels.

In an embodiment the flanges have opposing lips and the cover strips have co-operating ribs which engage the lips to retain the cover strips in the channels.

In a preferred embodiment the cover strips have curved outer faces which co-operate with outer faces of the flanges to provide a substantially circular external profile.

In an embodiment the tubular wall is hexagonal.

In an embodiment six flanges project from six corners of the hexagonal tubular wall.

In an embodiment the core section includes a hollow cylindrical portion. Ribs preferably extend outwardly from the hollow cylindrical portion. In an embodiment the ribs are T-shaped. -4 -

In an embodiment the ribs are arranged in pairs such that the outer faces of each pair are co-planar.

In an embodiment the structural assembly includes a bracket member having a wall surrounding a central duct with outwardly-extending flanges. In an embodiment the wall has a profile which corresponds to the tubular wall of the sleeve section.

In an embodiment the bracket member is interposed between the ends of two sleeve sections.

In an embodiment the flanges provide brackets which project beyond the flanges of the sleeve section.

In an embodiment the structural assembly includes spacing bars and/or bracing bars for connection between two bracket members In an embodiment the spacing bars and/or bracing bars have a curved external wall with a rigid central box section formed by two internal dividing walls.

In an embodiment the curved wall has at least one longitudinally-extending slot.

In an embodiment the ends of the spacing bars and/or bracing bars have one of the dividing walls and the associated portion of the curved wall removed for attachment to the bracket members. -5 -

In an embodiment the structural assembly includes foot members which include a base plate with an upstanding post. The post may be inserted into a sleeve section.

The invention also provides a structural assembly: - upright members (2, 6.1 and 6.2) which include bracket members (10); - a plurality of spacing bars (8) joined to the bracket members wherein each spacing bar interconnects two upright members at the same level; - bracing bars (9) joined to the bracket members wherein each bracing member interconnects two upright members at different levels.

In an embodiment the spacing bars support a work platform.

In an embodiment ballast blocks are suspended from the spacing bars.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description and the accompanying drawings referred to therein are included by way of non-limiting example in order to illustrate how the invention may be put into practice. In the drawings: Figure 1 is a general view of a structural assembly in the -6 -embodiment of a mobile phone mast assembly; Figure 2 is a general view showing one of the sleeve sections of the mobile phone mast assembly; Figure 3 is an end view of the sleeve section; Figure 4 is a general view showing one end of a cover strip for engagement with the sleeve sections; Figure 5 is a general view showing one of the core sections of the mobile phone mast assembly; Fiaure 6 is an end view of the core section; Fiaure 7 is a general view of a bracket member of the mobile phone mast assembly; Figure 8 is an end view of the bracket member; Figure 9 is a general view of one of the spacing bars of the mobile phone mast assembly; Figure 10 is an end view of the spacing bar; Figure 11 is a general view of an end portion of one of the bracing bars of the mobile phone mast assembly; -7 -Figure 12 is a general view of a foot member of the mobile phone mast assembly; Figure 13 is a side view of a second configuration of the mobile phone mast assembly; Figure 14 is a plan view of the second configuration; Figure 15 is a side view of a third configuration of the mobile phone mast assembly; Figure 16 is a plan view of the third configuration; Figure 17 is a side view of a fourth configuration of the mobile phone mast assembly; Figure 18 is a plan view of the fourth configuration.

DETAILED DESCRIPTION OF THE DRAWINGS

The structural assemblies described herein are principally formed of lightweight metal such as aluminium using purpose-made extruded sections cut to the required lengths.

Referring to Fig. 1, the mobile phone mast assembly 1 includes a vertical mast 2 which carries a mast-head antenna installation 3 clamped to the top of the mast and connected by one or more -8 -cables 4 to a communication unit 5 mounted at the base of the mast. Two outboard legs 6.1 and 6.2 are secured alongside the mast 2 in a triangular configuration. The outboard legs 6.1 and 6.2 are connected to the mast 2, and to each other, by horizontal spacing bars 8, and they are also connected to a higher point on the mast 2 by inclined bracing bars 9. In the embodiment shown, the mast 2 includes three sections 2a-2c of substantially the same length, and a shorter bottom section 2d. A bracket member 10 is inserted between each adjacent pair of sections 2a-2d. The sections are supported on a foot member 12 which is inserted into the lower end of the bottom section 2d. The two legs 6.1 and 6.2 each comprise a top section 6a and a bottom section 6b, the top and bottom sections again being separated by further bracket members 10. The bottom sections 6a also stand upon similar foot members 12.

The mast 2 and the legs 6.1 and 6.2 are all assembled from sleeve sections, core sections, and cover strips, which will now be described in detail. Referring to Fig.s 2 and 3, each of the sleeve sections 20 is of elongate shape and includes a tubular wall 21 of hexagonal cross section which defines a central duct 22. Six hollow flanges 23 extend outwardly from the six corners of the tubular wall, running along the length of the sleeve section, defining six channels 24. The outer end of each flange 23 has an end face 25 flanked by two lips 26 and 27, which are angled inwardly towards the hexagonal wall 21. Adjacent to the ends of each sleeve section (see Fig. 2) bolt holes 28 may be drilled through the wall 21 located within two channels 24 on opposite -9 -sides of the sleeve section.

Each of the channels 24 defined between the flanges 23 can be closed by a cover strip 30, one of which is shown in Fig. 4. The cover strip 30 has a convex part-circular outer face 31, on the underside of which are two locking ribs 32 and 33 which are inset slightly from the longitudinal edges of the strip. The locking ribs 32 and 33 have respective outwardly-directed hook formations 34 and 35 so that when the strip is pressed between two of the flanges 23 the hook formations snap-engage beneath the lips 26 and 27 to hold the cover strip in place. The cover strips can nevertheless be removed and re-fixed when required by springing the cover strips out of the channels 24. When all six of the channels are enclosed by cover strips 30 the end faces 25 of the flanges co-operate with the curved outer faces 31 of the cover strips to provide a substantially circular external profile.

Turning now to Fig.s 5 and 6, each of the core sections 40 includes a thick-walled tubular cylindrical inner portion 41. Twelve T-shaped ribs 42 extend outwardly from the cylindrical inner portion 41. These ribs are arranged in pairs such that the outer faces 43 of each pair (Fig. 6) lie on six planes (four of which are indicated, A-D) which define a hexagon. The core section 40 is a close sliding fit within the hexagonal wall 21 of the sleeve sections 20. Bolt holes 44 (Fig. 5) are drilled through the core section 40 at suitable positions, located centrally between each pair of ribs 42 on opposite sides of the core section. The cylindrical inner portion of the core section 40 provides the core section with -10 -considerable strength. The T-shaped ribs 42 enable the core section 40 to be located closely and non-rotatably within the sleeve sections 20 and allow the core section to be slid into the sleeve sections with minimum friction.

The core sections 40 provide a means whereby two of sleeve sections 20 can be joined end-to-end by inserting fixing bolts through suitably aligned bolt holes 28 and 44. In structures where the overall length of the interconnected sleeve sections is relatively short the core sections 40 need only be long enough to bridge the joint and receive the connecting bolts, but in longer assemblies the core sections can extend throughout the length of the structure to provide increased strength.

The channels 24 have several functions. They provide secure, enclosed, but easily accessible spaces to receive cables running up the mast. The enclosed channels also hide the bolts used to interconnect the sleeve sections and prevent casual access.

The bracket members 10, shown in Fig.s 7 and 8, each have a hexagonal wall 51, the external profile of which corresponds to the external profile of hexagonal wall 21 of sleeve sections 20. The inner surface of the wall 51 contains twelve T-shaped slots 52 (Fig. 8) surrounding a central duct 53. The bracket members can therefore be slid onto the core sections 40 with the ribs 42 located in the T-shaped slots 52 so that the bracket members may be interposed between the ends of two sleeve sections 20. Six flanges 54 extend outwardly from the six corners of the hexagonal wall 51. The flanges 54 are longer than the flanges 53 so that the ends of the flanges 54 form six projecting brackets 55 each containing a bolt hole 56. Part way along each flange 54 there are two lips 57 and 58, on opposite sides of the flange, which are angled inwardly towards the hexagonal wall 51. These lips correspond with the lips 26 and 27 of the flanges 21 so that the cover strips 30 may be engaged between the flanges 54 to form continuations of the enclosed channels 24. Aligned bolt holes 59 may be drilled through the hexagonal wall 51 on opposite sides of the bracket member to enable the bracket members to be fixed to the core sections by bolts inserted through appropriately positioned holes 44.

The horizontal spacing bars 8, shown in Fig.s 9 and 10, are of elongate shape. In end view, Fig. 10, the spacing bars 8 have a curved, generally oval external wall 61 with a rigid central box section formed by two internal dividing walls 62 and 63. On opposite sides of the spacer the oval wall 61 is divided by longitudinal slots 64 and 65 which allow various items to be attached to the bars using screw-threaded bolts which project through the slots with their heads retained inside the oval wall. The ends of the spacing bars are partially cut away at 66 by removing one of the dividing walls 63 and the associated portion of the oval wall 61. A bolt hole 67 is drilled through the exposed portion of the other dividing wall 62 so that the spacing bars may be bolted to the projecting brackets 55 of the bracket members 10. It will be noted that in the horizontal spacing bars the upper and lower portions 68 and 69 of the central box section are left in place -12 -so that the brackets 55 fit snugly between them, ensuring that the spacing bars are perpendicular to the upright members.

The bracing bars 8 are similar to the spacing bars but, as shown in Fig. 11, the upper and lower portions 68 and 69 of the central box section are removed with the dividing wall 63 so that the bracing bars can pivot about the bolts connecting them to the brackets 55 allowing the bracing bars to be fixed at an angle to the upright members.

The foot members 12, one of which is shown in Fig. 12, each include a base plate 80 with an upstanding post 81. The base plate 80 may include bolt holes 82 by which the assembly may be bolted down to a surface. The post 81 is dimensioned to be a close fit within the sleeve sections 20, to which the foot member may be secured by bolts inserted through bolt holes 83 in post 81.

From the foregoing it will be appreciated that structural assemblies such as the mobile phone mast of Fig. 1 can be constructed from the sleeve sections, core sections, cover strips, bracket members, spacing bars, bracing bars and foot members. These same elements can also be put together in numerous other combinations, a small number of which will now be briefly described by way of example.

A second configuration of mobile phone mast assembly, shown in Fig.s 13 and 14, includes a vertical mast 2 which carries three mast-head antenna installations 3.1, 3.2 and 3.3 attached to the -13 -top of the mast. Two outboard legs 6.1 and 6.2 are secured alongside the mast 2 in a triangular configuration. The antenna installations are connected by cables 4 to respective communication units 5.1, 5.2 and 5.3 mounted on the base of the mast 2 and the outboard legs 6.1 and 6.2. The cables 4 are routed along the channels enclosed by cover strips, as described above. The outboard legs 6.1 and 6.2 are connected to the mast 2, and to each other, by two sets of three horizontal spacing bars 8.1 and 8.2, one set located above the other, and they are also connected at different levels by inclined bracing bars 9. The spacing bars 8.1, 8.2 and the bracing bars 9 are joined to bracket members, as described above. The mast 2 and legs 6.1 and 6.2 are all supported on foot members 12. In this embodiment a triangular work platform 90 is secured to the lower set of spacing bars 8.1.

A third configuration of mobile phone mast assembly which is shown in Fig.s 15 and 16 includes three vertical masts 2.1, 2.2 and 2.3, arranged in a triangular configuration, which carry three mast-head antenna installations 3.1, 3.2 and 3.3 attached to the top of the respective masts. The antenna installations are connected by cables 4 to respective communication units 5.1, 5.2 and 5.3 mounted on the three masts below the respective antenna installations. Three outboard legs 6.1, 6.2 and 6.3 are secured alongside the masts 2, each leg being positioned in a triangular configuration with respect to two of the masts. The outboard legs 6.1, 6.2 and 6.3 are connected to the mast 2, and the masts are connected to each other, by a first set of horizontal spacing bars 8.1. Four (or more) further sets of spacing bars, 8.2 to 8.5, also -14 -interconnect the masts at various levels, and the masts and outboard legs are also connected at different levels by inclined bracing bars 9. The masts and the outboard legs are all supported on foot members 12. A triangular work platform 90 is secured to one set of spacing bars 8.3 to provide access to the antennas and communication units.

A fourth configuration of mobile phone mast assembly is shown in Fig.s 17 and 18. The assembly includes three vertical masts 2.1, 2.2 and 2.3, arranged in a triangular configuration. The three masts carry three stub masts 92 which are connected to the main masts by sets of horizontal spacing bars 8.5 and 8.6 and inclined bracing bars 9. The main masts and the stub masts each carry a mast-head antenna installations 3. The antenna installations are connected by cables 4 to various communication units 5 which are mounted on the three masts. Nine outboard legs 6 are secured around the base of the masts, connected to each other and to the masts by horizontal spacing bars 8.1. Three further sets of spacing bars, 8.2 to 8.4, also interconnect the masts at three further levels together with inclined bracing bars 9. A work platform 90, formed in triangular sections, is secured to the spacing bars 8.5 which connect the bottom of the stub masts 92 to provide access to the mast-head antenna installations 3. Triangular concrete ballast blocks 93 are suspended from the lowermost set of spacing bars 8.1 to assist in anchoring the mast assembly in high winds. The ballast blocks also form as a base platform which may support telecommunications cabinets and other equipment when required.

-15 -The structures described herein are therefore highly adaptable, lightweight, visually unobtrusive and are also aerodynamic to withstand high winds. The structures also provide protection and security for cables, which are nevertheless easily accessible.

Although the hexagonal shape is much preferred because it readily allows the formation of rigid triangular structures, other polygonal shapes would be possible, e.g. pentagonal, octagonal etc. Whilst the above description places emphasis on the areas which are believed to be new and addresses specific problems which have been identified, it is intended that the features disclosed herein may be used in any combination which is capable of providing a new and useful advance in the art.

Claims

-16 -CLAIMS1. A structural assembly: - an elongate sleeve section (20) having - a tubular wall (21) defining a duct (22), and - a plurality of flanges (23) extending outwardly from the tubular wall along the length thereof to define a plurality of channels (24); - a core section (40) receivable within the duct (22) of the elongate sleeve section; and - cover strips (30) for engagement between adjacent flanges (23) of the elongate sleeve section to close the channels (24).
2. A structural assembly according to Claim 1 having a plurality of elongate sleeve sections arranged end-to-end and connected together by one or more core sections.
3. A structural assembly according to Claim 2 having aligned holes in the sleeve sections and the core sections to receive bolts or other fastening elements.
4. A structural assembly according to Claim 3 wherein the holes are formed in the tubular wall of the sleeve sections and within the channels.
5. A structural assembly according to any preceding claim in which the flanges have opposing lips and the cover strips have -17 -co-operating ribs which engage the lips to retain the cover strips in the channels.
6. A structural assembly according to any preceding claim wherein the cover strips have curved outer faces which co-operate with outer faces of the flanges to provide a substantially circular external profile.
7. A structural assembly according to any preceding claim wherein the tubular wall is hexagonal.
8. A structural assembly according to Claim 7 wherein six flanges project from six corners of the hexagonal tubular wall.
9. A structural assembly according to any preceding claim wherein the core section includes a hollow cylindrical portion.
10. A structural assembly according to Claim 9 wherein ribs extend outwardly from the hollow cylindrical portion.
11. A structural assembly according to Claim 10 wherein ribs are substantially T-shaped.
12. A structural assembly according to Claim 11 wherein the ribs are arranged in pairs such that the outer faces of each pair are co-planar.
13. A structural assembly according to any preceding claim -18 -wherein the structural assembly includes a bracket member having a wall surrounding a central duct with outwardly-extending flanges.
14. A structural assembly according to Claim 13 wherein the wall of the bracket member has a profile which corresponds to the tubular wall of the sleeve section
15. A structural assembly according to Claim 13 or 14 wherein the bracket member interposed between the ends of two sleeve sections.
16. A structural assembly according to Claim 15 wherein the flanges provide brackets which project beyond the flanges of the sleeve section.
17. A structural assembly according to any preceding claim wherein the structural assembly includes spacing bars and/or bracing bars for connection between two bracket members.
18. A structural assembly according to Claim 17 wherein the spacing bars and/or bracing bars have a curved external wall with a rigid central box section formed by two internal dividing walls.
19. A structural assembly according to Claim 18 wherein the curved external wall has at least one longitudinally-extending slot.
20. A structural assembly according to Claim 18 or 19 -19 -wherein the ends of each spacing bar and/or bracing bar have one of the dividing walls and the associated portion of the curved external wall removed for attachment to the bracket members.
21. A structural assembly according to any preceding claim wherein the structural assembly includes foot members which include a base plate with an upstanding post.
22. A structural assembly according to Claim 21 wherein the post is inserted into a sleeve section.
23. A structural assembly: - upright members (2, 6.1 and 6.2) which include bracket members (10); - a plurality of spacing bars (8) joined to the bracket members wherein each spacing bar interconnects two upright members at the same level; - bracing bars (9) joined to the bracket members wherein each bracing member interconnects two upright members at different levels.
24. A structural assembly according to Claim 23 wherein the spacing bars support a work platform.
25. A structural assembly according to Claim 23 or 24 wherein ballast blocks are suspended from the spacing bars.