GB2544459A

GB2544459A - Structural support

Info

Publication number: GB2544459A
Application number: GB1518360.1A
Authority: GB
Inventors: Gabbitas Neil; Quinn Graeme
Original assignee: Hutchinson Engineering Ltd
Current assignee: Hutchinson Engineering Ltd
Priority date: 2015-10-16
Filing date: 2015-10-16
Publication date: 2017-05-24
Also published as: GB201518360D0

Abstract

The mast 2 comprises first and second plates 18, 20, each having concave and convex sides and attaching to each other along their convex sides to form a three pointed star, the first plate defining one point 14b, the second plate defining a second point 14c, and both plates defining a third point 14a. The convex side of a third plate may attach to the convex sides of the first two. The plates may be chevron-shaped. The mast may have a shroud for shielding antennas attached to the plates. Also claimed is a mast comprising first and second plates, each having concave and convex sides, the first plate having a longitudinal array of apertures, the second plate having a longitudinal array of tabs, the tabs being received in the apertures, and the plates form a three-pointed star, with two points being defined by the first plate and one by the second. Also claimed is a telecommunications array comprising the masts, and a kit of parts.

Description

Structural Support

The present invention relates to a structural support which has particular, but not exclusive, application to the telecommunications industry, where it can be used to support a set of telecommunications antennas. The present invention also relates to a telecommunications array which comprises such a structural support and also a set of telecommunications antennas.

Mobile telecommunications utilise a network of arrays of antennas which send signals to and from each other, and to and from mobile devices. To maximize the range of each antenna, the arrays usually position the antennas high above the ground. However, to ensure that each antenna covers the geographical area for which it is intended, the support structure of the array which holds the antenna up must be very rigid. This avoids the support flexing and thus pointing the antenna in a different direction than is intended. Typically, a deflection of 1° is the maximum allowable, regardless of the height of the support.

In rural areas, the supports for sets of antennas can generally be made suitably rigid without any particular problems arising. In urban areas, however, it is often desirable for the overall size of the array to be as small as possible, so as to be aesthetically unobtrusive and so as to fit in small spaces (for instance on roof tops, in narrow areas left unobstructed by air conditioning equipment and the like). Conventionally, a telecommunications array uses a simple hollow cylindrical post as the support for the antennas. However, the rigidity of such a support is dependent on its diameter, and there is therefore a trade-off between stiffness and overall size.

It is one object of the invention to mitigate or obviate one of the aforesaid disadvantages, and/or to provide an improved or alternative structural support or telecommunications array.

According to a first aspect of the present invention there is provided a structural support for a set of telecommunication antennas, wherein: the structural support defines a longitudinal axis; the structural support comprises a first plate and a second plate, each plate extending generally along the longitudinal axis and having a convex side and a concave side; the first and second plates are attached to one another with their convex sides abutting one another; and the first and second plates are arranged to form the general shape of a three-pointed star when viewed along the longitudinal axis, one point of the star being defined by the first plate, one point of the star being defined by the second plate, and one point of the star being defined by both the first and second plates.

The first and second plates may or may not be generally similar, or substantially identical, to one another. They may be attached to one another with their convex sides abutting directly, or abutting indirectly (for instance through a gasket positioned therebetween so as to damp vibration or compensate for the effects of thermal expansion). A three-pointed star may be considered to be any shape which comprises three outwardly-projecting portions attached to one another at a central hub, where each of said three portions are spaced from one another by an angle of less than 180 degrees.

Optionally: the structural support further comprises a third plate which extends generally along the longitudinal axis and which has a convex side and a concave side; the third plate is attached to the first and second plates with the convex side of the third plate abutting the convex sides of the first and second plates; and the first, second and third plates are arranged such that one point of the star is defined by the first and second plates, one point of the star is defined by the second and third plates, and one point of the star is defined by the third and first plates.

The presence of a third plate may advantageously increase the rigidity and/or stability of the structural support.

Each plate may be generally chevron-shaped when viewed along the longitudinal axis.

Alternatively, at least one of the plates may have a different shape. As an example, that plate may be generally arcuate, for instance taking the form of an arc of a circle or of an ellipse when viewed along the longitudinal axis, or may be arcuate with one or more flat sections.

The plates may be attached to one another using bolts, screws, rivets and/or adhesive. This may avoid warping, damage to surface coatings or molecular changes which may result from welding the plates to one another.

According to a second aspect of the present invention there is provided a structural support for a set of telecommunications antennas, wherein: the structural support defines a longitudinal axis; the structural support comprises a first plate and a second plate which each extend generally along the longitudinal axis; the first plate has a convex side and a concave side, and has a generally longitudinal array of apertures; the second plate has a generally longitudinal array of tabs extending therefrom; the plates are arranged such that at least some of the tabs are received in at least some of the apertures; the plates are arranged to form the general shape of a three-pointed star when viewed along the longitudinal axis, two points of the star being defined by the first plate, and the other point of the star being defined by the second plate.

All of the apertures may receive at least one tab, or some of the apertures may not receive a tab (at which point that aperture may receive a different component, such as a fastener, or may not receive a component at all). Similarly all of the tabs may be received in apertures in the first plate or one or more of the tabs may not be received in the aperture (at which point that tab may be received in an opening of a different component, such as a mounting socket of a clip for supporting wiring, or may not be received in any component at all).

The first plate may be generally chevron-shaped when viewed along the longitudinal axis.

The apertures may extend through the thickness of the first plate, and the tabs of the second plate received therein may pass all the way through the apertures and project from the concave side of the first plate.

Alternatively, the apertures may extend through the thickness of the first plate but the tabs may terminate within the apertures. As another alternative, the apertures may be recesses in the convex side of first plate but may not penetrate all the way through the plate to the concave side.

The plates may be joined together by welds between the tabs of the second plate and the material of the first plate which surrounds the apertures.

Alternatively or in addition, the plates may be joined together by welds in other areas, or may be joined together using a different mechanism, for instance using adhesive or fasteners.

Said welds may be full-penetration welds. A weld may be considered to be a full-penetration weld if the fusion zone extends across the full thickness of one of the plates.

Each tab may be welded to the first plate using two full-penetration welds.

The array of tabs may comprise long tabs and short tabs, the long tabs being received in the apertures in the first plate and the short tabs abutting the convex side of the first plate.

The short tabs may be welded to the first plate. Alternatively, the short tabs may be attached to the first plate using other means, such as adhesive or using fasteners. As another alternative, the short tabs may not be attached to the first plate at all.

The short tabs may be welded to the first plate with a full-penetration weld.

The short and long tabs may be arranged in the array in a repeating pattern.

The repeating pattern may have a repeating unit of a pair of long tabs followed by one short tab.

As an alternative, the repeating pattern may have any other suitable repeating unit such as a pair of short tabs followed by one long tab, three short tabs followed by two long tabs, or alternating single long tabs and short tabs.

Each aperture that receives a tab may receive at least two tabs.

In embodiments where each aperture that receives a tab receives at least two tabs, and where the array has a repeating unit of a pair of long tabs followed by one short tab, each pair of long tabs may be received in the same aperture.

As an alternative, each tab in each pair of long tabs may be received in a different aperture. For example, each aperture may receive two long tabs - a long tab from two different pairs of long tabs.

At least one of the plates may have at least one stiffening rib.

The stiffening rib may be positioned near the tip of one of the points of the three-pointed star.

The stiffening rib may be provided by a bend in that plate.

All of the plates may have stiffening ribs, the stiffening ribs being arranged such that each point of the star has a stiffening rib.

The three points of the star may be arranged at around 120 degree intervals.

The structural support may further comprise a mounting plate attached to one of its longitudinal ends, the mounting plate having a portion generally in the shape of a three-pointed star which is aligned with the three-pointed star defined by the plates, and mounting region configured for attachment to another component.

The structural support may further comprise a shroud positioned around the periphery of the three-pointed star defined by the plates, the shroud being configured to shield the plates, and a set of telecommunication antennas supported by the structural support, from the external environment.

The plates may be staggered along the longitudinal axis and axially overlap with each other.

At least one of the plates may be axially adjacent to an additional plate.

According to a third aspect of the present invention there is provided a telecommunications array comprising a structural support according to the first or second aspect of the invention, and a set of three telecommunication antennas, each antenna being positioned between two adjacent points of the three pointed star.

The telecommunications array may further comprise wiring connected to each of the antennas, the wiring for each antenna running behind that antenna, between the corresponding two points of the three-pointed star.

According to a fourth aspect of the present invention there is provided a kit of parts for assembling a structural support or a telecommunications array according to the first to third aspects of the invention.

Specific embodiments of the present invention will now be described with reference to the accompanying drawings in which:

Figure 1 is a schematic cross-sectional view of a conventional telecommunications array, viewed along the longitudinal axis of the structural support;

Figure 2 is a cross-sectional view of a structural support according to a first embodiment of the invention, viewed along its longitudinal axis;

Figure 3 is a cross-sectional view of two plates which form the structural support of figure 2, viewed along the longitudinal axis of the structural support;

Figure 4 is a cross-sectional view of a structural support according to a second embodiment of the invention, viewed along its longitudinal axis;

Figure 5 is a perspective view of the structural support of figure 4;

Figure 6 is a perspective view of a telecommunications array comprising the structural support of figures 4 and 5 with three telecommunications antennas attached thereto;

Figure 7 is a plan view of the telecommunications array of Figure 6;

Figure 8 is a perspective view of the telecommunications array of figures 6 and 7, showing the position of a shroud of the telecommunications array;

Figure 9 is a cross-sectional view of a structural support according to a third embodiment of the invention, viewed along its longitudinal axis;

Figure 10 is a cross-sectional view of a structural support according to a fourth embodiment of the invention, viewed along its longitudinal axis;

Figure 11 is a perspective view of the structural support of Figure 10;

Figure 12 is a perspective view of two plates which form the structural support of Figures 10 and 11;

Figure 13 is a cross-sectional view of the structural support of Figures 10 to 12, showing the position of welds between the two plates which make up the support;

Figure 14 is a cross-sectional view of the structural support of Figures 10 to 13, showing the position of additional welds between the two plates which make up the support;

Figure 15 is a cross-sectional view of a modification of the structural support of Figures 10 to 14, showing an alternative type of weld between the two plates which make up the support;

Figure 16 is an exploded view of a structural support according to a fifth embodiment of the invention;

Figure 17 is a perspective view of a structural support according to a sixth embodiment of the invention;

Figure 18 is an exploded view of part of the structural support of Figure 17; and

Figure 19 is a perspective view of a structural support according to a seventh embodiment of the invention.

Figure 1 is a schematic illustration of a conventional telecommunications array 1. In this example, the array 1 has a structural support 2 in the form of a hollow cylindrical post. The post 2 is elongate and defines a longitudinal axis 4 which runs into the page from the perspective of Figure 1. In this case, the array 1 has two telecommunications antennas 6a, 6b, which are attached to the post 2 by brackets 8 which attach to a collar 10 mounted on the post 2. The array 1 of Figure 1 is an example of an array which may be used to send signals in a substantially linear direction, for instance sending signals along a valley in a rural area.

The most readily apparent and easily-applicable way of increasing the stiffness of the post is to increase its diameter. As will be apparent from Figure 1,this would move the antennas 6a, 6b further apart, thereby increasing the overall size of the array 1. This illustrates the trade-off between reduced size and increased stiffness discussed above. For completeness, it would also be possible to increase stiffness up to a point by reducing the size of the central cavity of the post 2, but this would have a much smaller effect than increasing diameter, and would have a much greater impact on the overall weight of the post for a given increase in stiffness.

Figure 2 shows a cross-section of a structural support 2 according to a first embodiment of the invention. Like the structural support of Figure 1, the structural support 2 of this embodiment is elongate and defines a longitudinal axis 4 (which runs into the page from the perspective of Figure 2). Whereas in the example of Figure 1 the post was circular in cross-section, the structural support 2 of this embodiment is generally in the shape of a three-pointed star when viewed along its longitudinal axis 4. The structural support 2 has three “points”, 14a, 14b and 14c, with spaces 16a, 16b and 16c circumferentially disposed therebetween. In this particular embodiment the three points 14a - 14c are substantially evenly spaced about the circumference of the support 2, i.e. are positioned at around 120 degrees to one another. In other embodiments, however, the points 14a - 14c may be positioned unevenly about the circumference of the support 2.

The structural support 2 being generally in the shape of a three-pointed star may be beneficial in comparison to a structural support of the type shown in Figure 1 in that the material of the support is not all centrally located. For instance, as discussed below, by positioning antennas and wiring at least partially within the circumferential spaces 16a-16c, the rigidity of the structural support 2 can be increased (for instance by increasing the length of the points 14a-14c) without necessarily moving the antennas further outwards and increasing the overall size of the array.

The structural support 2 of this embodiment is formed from two plates, a first plate 18 and a second plate 20. The plates 18, 20 are generally elongate, and define respective longitudinal axes (not labelled) which are generally parallel to the longitudinal axis of the structural support 2 when assembled. In this embodiment, the first and second plates 18, 20 are generally the same shape as one another, and more particularly in this case are substantially identical. In other embodiments, however, the first and second plates may be of differing shapes (for instance they may have different cross-sectional shapes when viewed along their longitudinal axes, and/or may be of different thicknesses).

The first and second plates 18, 20 are shown separate from one another in Figure 3. As shown more clearly in this figure, each plate 18, 20 has a convex side 22 and a concave side 24. In this case, the concave and the convex sides are formed by a bend 26. In this particular case, each bend 26 has a relatively tight radius and is positioned generally in the middle of the plate in question when viewed along the longitudinal axis of that plate, and the remainder of each plate is substantially flat. Each plate 18, 20 is therefore generally chevron-shaped in longitudinal cross-section. In other embodiments, however, the plates may be shaped differently. For instance, one or both of the first and second plates 18, 20 may be curved, for instance having the shape of an arc of a circle or an ellipse when viewed along its longitudinal axis, or may have any other suitable shape.

Returning to Figure 2, it can be seen that the structural support 2 is formed by attaching the first and second plates 18, 20 to one another with their convex sides 22 abutting. In this particular case, the convex sides 22 of the plates 18, 20 abut directly, but in other embodiments there may be another component, such as a gasket arranged to reduce vibration or to compensate the effects of thermal expansion, positioned therebetween. Similarly, in this embodiment the plates 18, 20 are joined using nuts 28 and bolts 30 passing through holes (not shown) in the plates. In other embodiments, however, the plates may be attached to one another using any other suitable mechanism, such as using rivets, clinch joints, spot welds or adhesive.

As can be seen by comparing Figures 2 and 3, the plates 18, 20 are arranged to form the three-pointed star shape of the structural support 2, with one point 14b of the star being defined by the first plate 18, one point 14c of the star being defined by the second plate 20, and one point 14a of the star being defined by both the first and second plates. A structural support according to a second embodiment of the invention is shown in Figures 4 and 5. The second embodiment is similar to the first embodiment, therefore only the differences will be described here. As with the first embodiment, the structural support 2 of the second embodiment has a first plate 18 and a second plate 20, arranged with convex sides abutting so that the first plate defines one point 14b of the three-pointed star formed by the structural support, the second plate defines one point 14c of the star, and the first and second plates both define one point 14a of the star. In this case, however, the structural support 2 comprises a third plate 32.

In this embodiment, the third plate 32 is attached to the first and second plates, 18, 20 with its convex surface (not labelled) abutting the convex surfaces of the first and second plates. Accordingly, in this embodiment, point 14a of the three-pointed star is defined by the first and second plates 18, 20, as with the first embodiment. However, in this embodiment, point 14b of the star is defined not only by the first plate 18, but also by the second plate 32. Similarly, point 14c of the three-pointed star is defined not only by the second plate 20, but by the third plate 32.

In this case, the third plate is generally the same as the first and second plates 18, 20. More specifically, the third plate 32 is substantially identical to each of the first and second plates. However, in other embodiments this may not be the case. Further, in embodiments where the first and second plates differ from one another, the third plate may be substantially the same as the first plate, the second plate, or neither. In this case the third plate is attached to the first and second plates 18, 20, using nuts 28 and bolts 30, i.e. in the same manner as the first and second plates are attached to one another, but in other embodiments the third plate may be attached to the first plate and/or the second plate using a different mechanism than that used to attach the first plate to the second plate. In addition, in some embodiments the third plate may be attached to one of the first and second plates only by virtue of being attached to the other. For instance, the third plate may abut the first and second plates, but may be attached to the first plate only by virtue of being attached to the second plate. A complete telecommunications array according to the second embodiment of the invention is shown in Figures 6 to 8. The array 1 of this embodiment comprises the structural support 2 described above with reference to figures 4 and 5, and a set of three telecommunications antennas 6a - 6c. As shown more clearly in Figure 7, the three antennas 6a - 6c are positioned partially within the circumferential spaces 16a -16c between the points 14a - 14c of the three-pointed star defined by the structural support 2. With the antennas 6a - 6c positioned in this way, wiring (not shown) connected thereto can be positioned radially behind the antennas, running through the spaces 16a - 16c. This is beneficial in comparison to a convention structural support such as that shown in Figure 1 in that wiring being positioned behind the antennas does not mean that the antennas must be positioned further radially outwards. Referring briefly to Figure 1, to accommodate wiring between the antennas 6a and 6b, the brackets 8 would have to be enlarged in the radial direction so as to make room, and this would increase the overall size of the array. The only alternative would be to make a hole in the structural support 2 so as to run wiring up its centre, however this is undesirable since it affects the structural integrity and the stiffness of the support.

Returning to Figures 6 to 8, with the antennas 6a - 6c positioned partially within the circumferential spaces 16a - 16c between the points 14a - 14c, the stiffness of the structural support 2 could be increased by extending the radial length of the points 14a - 14c of the three-pointed star, without needing the antennas 6a - 6c to be moved outwards (i.e. without increasing the overall size of the array 1). This is shown most clearly in Figure 7, and is discussed in more detail below.

Figure 8 shows the telecommunications array 1 complete with a shroud 34 positioned around the support structure 2 and antennas 6a - 6c. The shroud 34 is positioned so as to shield the support structure 2 and antennas 6a - 6c from the environment, for instance to improve the aesthetics of the array 1, and/or to prevent corrosion due to water ingress. The shroud 34 is made of a material which does not interfere with transmission to and from the antennas to any significant extent. In this embodiment the shroud extends axially above and below the antennas 6a - 6c and structural support 2, however in other embodiments this may not be the case. For instance, the shroud 34 may be positioned over only a top portion of the antennas 6a - 6c and structural support 2, at which point the remaining portions of these components may be shielded by other means such as a skirt projecting from a surface upon which the array 1 is mounted, or may be left exposed (for instance where the antennas and structural support are corrosion resistant, and are hidden from view by the edge of a building).

It can be seen from Figure 8 that in this embodiment, the shroud 34 is positioned immediately radially outwards from the antennas 6a - 6c, so as to add as little as possible to the overall diameter of the array 1. It can also be seen that in this particular embodiment the points 14a - 14c of the three-pointed star formed by the structural support 2 terminate at a point around half the radius of the shroud 34. Accordingly, it would be possible for the radial length of the points 14a - 14c (sometimes referred to as the ‘outreach’ of the points) to be approximately doubled, so as to significantly increase the stiffness of the support 2, without having any effect on the diameter of the shroud 34 (i.e. the overall size of the array 1). A structural support to according to a third embodiment of the invention is shown in Figure 9. The structural support 2 of this embodiment is similar to that of the previous embodiment, therefore only the differences will be described here. In this embodiment, each plate 18, 20, 32 has two stiffening ribs 38a, 38b. The stiffening ribs 38a, 38b are positioned on the plates 18, 20, 32 such that the three-pointed star defined by the structural support 2 has stiffening ribs 38 at each of its points 14a - 14c (in this case two stiffening ribs at each point). The stiffening ribs 38a, 38b can serve to increase the strength of the structural support 2 (without having any significant effect on the overall size of the support), and may also serve as attachment points for other components.

In this embodiment, the stiffening ribs 38a, 38b are positioned at the edges of each plate 18, 20, 32 so that they lie at the distal tips of the points 14a - 14c. In other embodiments, however, the stiffening ribs may be located at a location on the plates 14a - 14c further radially inwards. Furthermore, in other embodiments the different stiffening ribs 38a, 38b may be of differing sizes, shapes and/or positions relative to the plate/point on which they are provided.

In another example of a structural support which includes at least one stiffening rib, each of the first, second and third plates have a single stiffening rib, and the plates are arranged so each point of the three-pointed star is provided with one of the stiffening ribs. In another example, only one of the plates has a stiffening rib (and therefore only one of the points of the three-pointed star has a stiffening rib).

In the third embodiment of the invention, each stiffening rib 38a, 38b is provided by a bend (in this case a substantially 90° bend) in the plate 18, 20, 32 on which that rib is provided. In other embodiments, however, the rib may take another form such as a section of plate of enlarged thickness, or a bulge or projection extending from a side of the plate in question. A fourth embodiment of the invention is shown in Figures 10 and 11. In this embodiment, like the embodiments described above, the structural support 2 is elongate and defines a longitudinal axis (not visible but running into the page from the perspective of Figure 10 and running vertically from the perspective of Figure 11). Also as with the previous embodiments, the structural support 2 comprises a first plate 18 and second plate 20 attached to one another so as to give the structural support the general shape of a 3-pointed star when viewed along its longitudinal axis. In this case, however, the first plate 18 defines two points 14a, 14b of the star, and the second plate 20 defines one point 14c of the star. In this particular case, as with previous embodiments, the first plate 18 has a convex side 22 and a concave side 24 provided by a bend 26, however in this particular case the second plate 20 is substantially flat.

The first and second plates of the fourth embodiment of the invention are shown separate from one another in Figure 12. Referring to Figures 10-12 in combination, it can be seen that the first plate has a generally longitudinal array 50 of apertures 52, and the second plate 20 has a generally longitudinal array 54 of tabs 56. In this particular case, the array 50 of apertures 52 in the first plate 18 is substantially linear and is positioned substantially longitudinally. Further, in this particular case the apertures 52 are substantially evenly spaced throughout the array 50, and the apertures 52 are provided in the bend 26 of the plate. In this case, each of the apertures 52 takes the form of a slot configured to receive two tabs 56 of the second plate 20, as discussed in more detail below. In other embodiments, however, the array 50 of apertures 52 may take any other suitable form. For instance, the apertures may be provided in a flat portion of the first plate, may take the form of generally circular holes, may be unevenly spaced within the array, and/or the array may extend diagonally to some extent relative to the longitudinal axis.

Turning to the second plate 20, in this case the array 54 of tabs 56 is substantially longitudinally aligned and the tabs are substantially evenly spaced within the array. The tabs 56 of this embodiment are generally rectangular, and are therefore complementary to the shapes of the apertures 52. The tabs 56 in this case extend from an edge of the second plate 20, projecting generally within the plane of the plate. In other embodiments, however, the array 54 or tabs 56 may take any other suitable form. For instance, the tabs may be unevenly spaced, the array may extend diagonally to some extent relative to the longitudinal axis, may extend out of the plane of the plate (where the second plate is flat), etc. The array 54 of the fourth embodiment comprises long tabs 56a and short tabs 56b in a repeating pattern, in this case the repeating unit being a pair of long tabs followed by one short tab.

In the structural support 2, the first plate 18 and the second plate 20 are attached together such that at least some of the apertures 52 receive at least some of the tabs 56 therein. More particularly, in this embodiment, the apertures 52 extend through the thickness of the first plate 18, and the tabs 56 received therein pass all the way through the aperture from the convex side 22 of the first plate and project from the concave side 24. This is shown most clearly in Figure 10. In this particular embodiment, each aperture 52 receives both adjacent long tabs 56a of the pair, and the short tabs 56b between each pair of long tabs 56a abut the convex side 22 of the first plate 18.

The tabs 56a of the second plate 20 being received in (and in this case through) the apertures 52 in the first plate 18 provides a degree of interlock between the first and second plates. This, in turn, reduces the extent to which further means must be provided to attach the first and second plates 18, 20. For instance, it could allow fewer fasteners to be used to attach the plates together, where fasteners are used, or may reduce the amount of welding needed where the plates are welded together.

In this embodiment, the first and second plates 18, 20 are welded to one another. More particularly, the first plate 18 is welded to the tabs 56 of the second plate 20. Welding the first and second plates 18, 20 at the discrete locations of the tabs 56, rather than producing a continuous seam weld between the two plates, may advantageously reduce the amount of warping produced by the plates. It may also reduce the extent of any damage to surface treatments applied to the plates, and/or any change in molecular properties of the material of the plates, which heat from the welding process may cause.

In this case, welds are provided between each tab that is received in an aperture 52 (i.e. each long tab 56a), and material of the first plate which surrounds the aperture 52 in which that tab is received. More particularly, each tab 56a which is received in an aperture 52 is welded to the material of the first plate which surrounds that aperture. Figure 13 shows a cross-section through the structural support 2 a point along the longitudinal axis at which one of the long tabs 56a is received in one of the apertures 52 and welded to the first plate. As shown in this figure, in this particular case, each tab 56a is welded to the first plate using two full penetration welds 58, 60. Furthermore, the tips of the tabs 65a, which protrude from the apertures, are welded to the first plate 18 using a double fillet weld 62.

In addition to welds between the long tabs and the material surrounding their corresponding apertures, in this embodiment each short tab of the second plate is welded to the convex side of the first plate. Figure 14 is a cross-section through the structural support 2 at a point along the longitudinal axis at which one of the short tabs 56b is so welded. In this case, the tab 56b is welded to the convex side 22 (or particularly to the portion of the convex side 22 provided by the bend 26, using a double fillet weld 62.

In a modification of the fourth embodiment, the short tabs 56b are welded to the convex side 22 of the first plate 18 using a full penetration weld 64. This modification is shown in Figure 15. A fifth embodiment of the invention is shown in Figure 16. The fifth embodiment is similar to the fourth embodiment, therefore only the differences will be described in detail. In the fifth embodiment, each of the plates 18, 20 is provided with a stiffening rib 38. The stiffening ribs 38 are arranged on the plates such that when the structural support is assembled, each point of the three-pointed star has a stiffening rib positioned at its tip. In this case, each stiffening rib 38 is attached to the corresponding plate 18, 20 via an array of auxiliary tabs 66 to which the stiffening rib is welded. The stiffening ribs 38 being welded to the plates 18, 20 in discrete locations (i.e. at the auxiliary tabs 66) may provide advantageously reduced warping due to heat from the welding as discussed above in relation to the first and second plates 18, 20 being welded to one another at the tabs 56.

The structural support 2 of the fifth embodiment also has a mounting plate 72. In this case the structural support 2 has a mounting plate 72 attached to each of its axial ends. In this case the mounting plates 72 are attached to the structural support 2 using welds, for instance full-penetration welds or fillet welds. The mounting plate 72 has a portion 74 generally in the shape of a three-pointed star, this portion being aligned with the three-pointed star defined by the plates 18, 20. The mounting plate 72 also has a mounting region 76, which in this embodiment takes the form of an annular region encircling the portion 74 which is generally in the shape of a three-pointed star. The annular region 76 has mounting features 78 configured to receive fasteners by which the mounting plate 72 (and thus the structural support 2 as a whole) can be mounted. For instance, the structural support 2 may be mounted on top of a support post, and attached to the support post via one of the mounting plates 72. As an alternative, the structural support 2 may extend from a surface such as a building roof, and be attached to that surface via one of the mounting plates 72. Circumferentially between the portions of the region 74 which define the tips of the three-pointed star are cavities 80 which are aligned with the gaps between the points of the three-pointed star defined by the plates 18, 20. Cables received within the gaps between the points of the star defined by the plates 18, 20 can pass through the cavities 80, rather than having to circumnavigate the mounting plate 72. A sixth embodiment of the invention is shown in Figure 17. This embodiment comprises first, second and third plates 18, 20, 32, which are substantially the same as those plates in the second embodiment and which are arranged in substantially the same way so as to form a three-pointed star. In this embodiment, however, the structural support comprises three additional plates - an additional first plate 18’, and additional second plate 20’ and an additional third plate 32’. In this embodiment, each additional plate 18’, 20’, 32’ is substantially identical to its corresponding plate 18, 20, 32 (and indeed the plates 18, 20, 32 are substantially identical, as indicated above, therefore all six plates 18, 18’, 20, 20’, 32, 32’ are substantially identical). In other embodiments, however, one or more of the additional plates 18’, 20’, 32’ may differ from its corresponding plate 18, 20, 32.

In this embodiment the additional plates 18’, 20’, 32’ are positioned axially adjacent to their respective plates 18, 20, 32, and abut their respective plates at a seam 83. The additional plates 18’, 20’, 32’ of this embodiment are arranged in corresponding relative positions to the plates 18, 20, 32 about the longitudinal axis of the structural support 2, and thereby continue the three-pointed star cross-section of the structural support.

In this embodiment, each plate 18, 20, 32 is attached to the corresponding additional plate 18’, 20’ 32’ by pairs of counterposed joining panels 82a, 82b (only one panel of each pair being visible in Figure 17) which axially overlap both plates and bridge the seam 83 therebetween. In this case the panels 82a, 82b of each pair are positioned on opposite sides of a corresponding point 14a, 14b, 14c of the three-pointed star, and sandwich between them the plates 18, 18’, 20, 20’, 32, 32’ that make up that point (as discussed in more detail below). The panels 82a, 82b of each pair are attached to one another using nuts 84 and bolts 86, the bolts running through the panels 82a, 82b and the plates 18, 18’, 20, 20’, 32, 32’ sandwiched therebetween.

Figure 18 shows the arrangement of the pairs of mounting panels 82a, 82b more clearly. Taking the example of the pair of panels 82a, 82b positioned on point 14a (i.e. the pair in the foreground of Figure 18, shown in exploded view), panel 82a axially overlaps the first plate 18 and the additional first plate 18’, and panel 82b axially overlaps the second plate 20 and the additional second plate 20’. In this case the panels 82a, 82b overlap their respective plates 18, 18’, 20, 20’ by equal amounts, i.e. the panels are positioned with the seam 83 at their axial mid-points. Each panel 82a, 82b has a set of eight apertures 81, four of which lie above the seam 83 (in use, from the perspective of Figure 18) and four of which lie below the seam.

To attach the additional first plate 18’ to the first plate 18 and the additional second plate 20’ to the second plate 20, the mounting panels 82a, 82b are positioned across the seam 83, on either side of the point 14a of the star. The panels 82a, 82b are then bolted together, sandwiching the plates 18, 18’, 20, 20’ therebetween. More particularly, above the seam 83 four bolts 86 are passed through the upper four apertures 81 in panel 82a (from the perspective of Figure 18), through the first plate 18, through the second plate 20, through the upper four apertures 81 in panel 82b, through two washers 86 per bolt, and into complimentary nuts 84. Similarly, below the seam 83 four bolts 86 are passed through the lower four apertures 81 in panel 82a, through the additional first plate 18’, through the additional second plate 20’, through the upper four apertures 81 in panel 82b, through two washers 86 per bolt, and into complimentary nuts 84.

Tightening the nuts 84 and bolts 86 urges the two mounting panels 82a, 82b towards one another, clamping together the plates 18, 18', 20, 20’ that are sandwiched between the panels. The panels 82a, 82b therefore also act to attach the first plate 18 to the second plate 20, and the additional first plate 18’ to the additional second plate 20’. In some embodiments the means by which the additional plates 18’, 20’ are attached to their respective plates 18, 20 is may be the sole means by which the plates 18, 20 are attached to one another. In this embodiment, however, the plates 18, 20 are also attached to one another using nuts 28 and bolts 30, as described above in relation to the second embodiment.

As is shown in Figures 17 and 18, the structural support 2 has a total of three pairs of mounting panels 82a, 82b - one pair on point 14a (the pair described above), one pair on point 14b and one pair on point 14c. The pair on point 14b attaches the additional first plate 18’ to the first plate 18 and the additional third plate 32’ to the third plate 32, and also attaches the first plate 18 to the third plate 32 and the additional first plate 18’ to the additional third plate 32’. Similarly, the pair of mounting panels 82a, 82b on point 14c attaches the additional second plate 20’ to the second plate 20 and the additional third plate 32’ to the third plate 32, and also attaches the second plate 20 to the third plate 32 and the additional second plate 20’ to the additional third plate 32’.

It will therefore be apparent that each additional plate 18’, 20’, 32’ is attached to its corresponding plate 18, 20, 32 by two pairs of mounting panels 82a, 82b. For instance, the additional first plate 18’ is attached to the first plate 18 by the pair of mounting panels 82a, 82b on point 14a of the star, and by the pair of mounting panels on point 14b of the star. Similarly, the additional second plate 20’ is attached to the second plate 20 by the pair of mounting panels 82a, 82b on point 14a of the star, and by the pair of mounting panels on point 14c of the star. A seventh embodiment of the invention is shown in Figure 19. Like the sixth embodiment, the support structure 2 of this embodiment has first, second and third plates 18, 20, 32 arranged to give the support structure a cross section generally in the shape of three-pointed star with points 14a, 14b and 14c. Also like the sixth embodiment, the seventh embodiment has an additional first plate 18’, additional second plate 20’ and additional third plate 32’ positioned axially adjacent to their corresponding plates 18, 20, 32. However, the support structure 2 of the seventh embodiment also has a further additional second plate 20”. This plate 20” is axially adjacent to the additional second plate 20’, at the opposite end of the additional first plate to the second plate 20.

In this case, the additional plates 18’, 20’, 32’ are attached to their respective plates 18, 20, 32 using mounting panels 82, nuts 84 and bolts 86 as with the sixth embodiment. In this case, however, axially adjacent plates are joined together using a single mounting panel 82, rather than a pair. Taking the example of the mounting panel 82 which attaches the additional second plate 20’ to the second plate 20 (i.e. the highest mounting panel from the perspective of Figure 19), bolts 86 above the seam 83 run through the mounting panel 82, through the second plate 20, through the third plate 32 and into nuts (not visible). Bolts 86 below the seam 83 run through the mounting panel 82, through the additional second plate 20’, through the third plate 32 and into nuts (not visible). As another example, in the mounting panel 82 which attaches additional second plate 20” to additional second plate 20’ (i.e. the lowest mounting panel from the perspective of Figure 19, which is shown as hidden detail), bolts (not visible) above the seam (not visible) run through the mounting panel 82, through additional second plate 20”, through the first plate 18 and into nuts 84. Bolts below the seam run through the mounting panel 82, through additional second plate 20”, through the first plate 18 and into nuts 84.

As with the sixth embodiment, in the seventh embodiment the mechanism by which additional plates 18’, 20’, 20”, 32’ are mounted to their respective plates 18, 20, 32 also serves to attach the first, second and third plates 18, 20, 32 to one another (and also serves to attach the additional first, second and third plates 18’, 20’, 32’ to each other). In this embodiment, there is no further mechanism by which the first, second and third plates 18, 20, 32 (or the additional plates 18’, 20’, 20”, 32’) are attached to one another, save for mounting plates (not visible) at either end of the support structure 2.

Returning briefly to Figures 17 and 18, it can be seen that the first, second and third plates 18, 20, 32 are axially coincident, that is to say that the three plates occupy substantially the same axial space as each other. As a result, the lower axial ends of the plates 18, 20, 32 (from the perspective of Figures 17 and 18) terminate at substantially the same axial location, meaning that support structure 2 has a seam 83 running through the entire structure at that point, where each plate attaches to its corresponding additional plate. In contrast, returning to Figure 19, in the seventh embodiment the first, second and third plates 18, 20, 32 are staggered along the longitudinal axis of the support structure 2. In other words, one of the first, second and third plates 18, 20, 32 has an axial end which terminates at a different axial position to the corresponding end of another one of the first, second and third plates. More particularly, in this particular embodiment each of the first, second and third plates 18, 20, 32 has a lower axial end (from the perspective of Figure 19) which terminates at a different axial position to either of the other two plates - the bottom end of the second plate 20 terminates at the axially lowest position, the bottom end of the first plate 28 terminates at the axially highest position, and the bottom end of the third plate 32 terminates at an axial position between the bottom ends of the first and second plates. In this particular case, the first, second and third plates 18, 20, 32 terminate at their upper ends at substantially the same axial position.

Although the first, second and third plates 18, 20, 32 are staggered along the longitudinal axis, they nonetheless axially overlap with each other. That is to say that throughout the total axial distance covered by the three plates, there is no axial position which is not occupied by at least one of the plates. In this case each plate axially overlaps with both the other plates. However, in other embodiments with three staggered plates that axially overlap each other, one or more of the plates may only axially overlap with one of the other plates. For instance, the first plate may axially overlap with the second plate but not the third plate (the third plate therefore axially overlapping with the second plate but not the first plate).

One potential advantage of the first, second and third plates being axially staggered but axially overlapping, as is the case in the seventh embodiment, is that the seams between those plates and additional plates (where present) are not axially coincident. This can improve the strength of the support structure as a whole. For instance, referring back to Figures 17 and 18, as noted above in the sixth embodiment there is a seam 83 throughout the support structure 2 at the axial position at which the first, second and third plates 18, 20, 23 are attached to the additional first, second and third plates 18’, 20’, 32’. This can introduce a potential weak point in the structure. In contrast, as shown in Figure 19, in the seventh embodiment the seams 83 between the first, second and third plates 18, 20, 32 and their respective additional plates 18’, 20’ 32’ are axially offset from one another. This can mean that any weakness introduced by an individual seam 83 is not compounded by proximity to other seams. In other words, any inherent weakness introduced by the seams 83 is spread over the support structure 2, rather than being concentrated at a single axial positon.

The described and illustrated embodiments are to be considered as illustrative and not restrictive in character, it being understood that only preferred embodiments have been shown and described and that all changes and modifications that come within the scope of the invention as defined in the claims are desired to be protected. For instance, whilst in the above embodiments the additional plates are attached to their respective plates via nuts and bolts and one or more mounting panels, in other embodiments a different mechanism may be used. For instance, mounting panels may be used but these may be attached using rivets, adhesive or welding. As another example, the additional plates may abut and be welded end-to-end with their respective plates, or may overlap axially with their respective plates and be joined in the overlapping region using welding, adhesive or fasteners. It should also be understood that different additional plates may be attached to their respective plates in different ways to each other.

In the sixth and seventh embodiments, plates that are axially adjacent to one another abut one another. However, in other embodiments there may be gap or another element (for instance a gasket positioned to damp vibration or compensate for the effects of thermal expansion) positioned between two axially adjacent plates. In addition, it is to be understood that two ‘axially adjacent’ plates may axially overlap with one another.

Whilst the concept of additional plates has been described above in relation to the first aspect of the invention, the idea is equally applicable to the second aspect of the invention. For instance, in a modification of the fourth embodiment of the invention, the first plate may be approximately half the axial length of the first plate of the fourth embodiment, and the shortened first plate may be axially adjacent to an additional first plate which is also attached to the second plate. In such an embodiment the first and second plates would be staggered along the longitudinal axis and axially overlap with one another.

Although the sixth and seventh embodiments have been described in relation to the lower set of plates (from the perspective of Figures 17 to 19) being the ‘additional plates’, it is to be understood that it may equally be considered that the upper set of plates are the ‘additional plates’, or that one additional plate is positioned on one axial end of its respective plate, and other additional plate is positioned on the other axial end of its respective plate.

Although the invention has been described above in relation to the support structure being oriented vertically, it is to be understood that the support structure can be positioned in any suitable orientation, for instance it may be arranged horizontally or diagonally.

In relation to the claims, it is intended that when words such as "a," "an," "at least one," or "at least one portion" are used to preface a feature there is no intention to limit the claim to only one such feature unless specifically stated to the contrary in the claim. When the language "at least a portion" and/or "a portion" is used the item can include a portion and/or the entire item unless specifically stated to the contrary.

Optional and/or preferred features as set out herein may be used either individually or in combination with each other where appropriate and particularly in the combinations as set out in the accompanying claims. The optional and/or preferred features for each aspect of the invention are also applicable to any other aspects of the invention where appropriate.

Claims

CLAIMS:

1. A structural support for a set of telecommunication antennas, wherein: the structural support defines a longitudinal axis; the structural support comprises a first plate and a second plate, each plate extending generally along the longitudinal axis and having a convex side and a concave side; the first and second plates are attached to one another with their convex sides abutting one another; and the first and second plates are arranged to form the general shape of a three-pointed star when viewed along the longitudinal axis, one point of the star being defined by the first plate, one point of the star being defined by the second plate, and one point of the star being defined by both the first and second plates.

2. A structural support according to claim 1 wherein: the structural support further comprises a third plate which extends generally along the longitudinal axis and which has a convex side and a concave side; the third plate is attached to the first and second plates with the convex side of the third plate abutting the convex sides of the first and second plates; and the first, second and third plates are arranged such that one point of the star is defined by the first and second plates, one point of the star is defined by the second and third plates, and one point of the star is defined by the third and first plates.

3. A structural support according to claim 1 or claim 2 wherein each plate is generally chevron-shaped when viewed along the longitudinal axis.

4. A structural support according to any preceding claim wherein the plates are attached to one another using bolts, screws, rivets and/or adhesive.

5. A structural support for a set of telecommunications antennas, wherein: the structural support defines a longitudinal axis; the structural support comprises a first plate and a second plate which each extend generally along the longitudinal axis; the first plate has a convex side and a concave side, and has a generally longitudinal array of apertures; the second plate has a generally longitudinal array of tabs extending therefrom; the plates are arranged such that at least some of the tabs are received in at least some of the apertures; the plates are arranged to form the general shape of a three-pointed star when viewed along the longitudinal axis, two points of the star being defined by the first plate, and the other point of the star being defined by the second plate.

6. A structural support according to claim 5, wherein the first plate is generally chevronshaped when viewed along the longitudinal axis.

7. A structural support according to claim 5 or 6 wherein the apertures extend through the thickness of the first plate, and the tabs of the second plate received therein pass all the way through the apertures and project from the concave side of the first plate.

8. A structural support according to any one of claims 5 to 7 wherein the plates are joined together by welds between the tabs of the second plate and the material of the first plate which surrounds the apertures.

9. A structural support according to claim 8 wherein said welds are full-penetration welds.

10. A structural support according to claim 9 wherein each tab is welded to the first plate using two full-penetration welds.

11. A structural support according to any one of claims 5 to 10 wherein the array of tabs comprises long tabs and short tabs, the long tabs being received in the apertures in the first plate and the short tabs abutting the convex side of the first plate.

12. A structural support according to claim 11 wherein the short tabs are welded to the first plate.

13. A structural support according to claim 12 wherein the short tabs are welded to the first plate with a full-penetration weld.

14. A structural support according to any one of claims 11 to 13 wherein the short and long tabs are arranged in the array in a repeating pattern.

15. A structural support according to claim 14 wherein the repeating pattern has a repeating unit of a pair of long tabs followed by one short tab.

16. A structural support according to any preceding claim wherein each aperture that receives a tab receives at least two tabs.

17. A structural support according to claim 16 when dependent on claim 15, wherein each pair of long tabs is received in the same aperture.

18. A structural support according to any preceding claim wherein at least one of the plates has at least one stiffening rib.

19. A structural support according to claim 18 wherein the stiffening rib is provided by a bend in that plate.

20. A structural support according to claim 18 or 19 wherein all of the plates have stiffening ribs, the stiffening ribs being arranged such that each point of the star has a stiffening rib.

21. A structural support according to any preceding claim wherein the three points of the star are arranged at around 120 degree intervals.

22. A structural support according to any preceding claim further comprising a mounting plate attached to one of its longitudinal ends, the mounting plate having a portion generally in the shape of a three-pointed star which is aligned with the three-pointed star defined by the plates, and mounting region configured for attachment to another component.

23. A structural support according to any preceding claim further comprising a shroud positioned around the periphery of the three-pointed star defined by the plates, the shroud being configured to shield the plates, and a set of telecommunication antennas supported by the structural support, from the external environment.

24. A structural support according to any preceding claim wherein the plates are staggered along the longitudinal axis and axially overlap with each other.

25. A structural support according to any preceding claim wherein at least one of the plates is axially adjacent to an additional plate.

26. A telecommunications array comprising a structural support according to any preceding claim, and a set of three telecommunication antennas, each antenna being positioned between two adjacent points of the three pointed star.

27. A telecommunications array according to claim 26 further comprising wiring connected to each of the antennas, the wiring for each antenna running behind that antenna, between the corresponding two points of the three-pointed star.

28. A kit of parts for assembling a structural support or a telecommunications array according to any preceding claim.