WO2001015264A1

WO2001015264A1 - Telecommunication mast with ladder arrangement

Info

Publication number: WO2001015264A1
Application number: PCT/ZA2000/000150
Authority: WO
Inventors: David W. O'bray; Trevor C. Burden
Original assignee: Dorbyl Limited
Priority date: 1999-08-26
Filing date: 2000-08-25
Publication date: 2001-03-01
Also published as: AU6806000A

Abstract

According to the present invention a telecommunication mast comprises an elongate mast member and a plurality of step formations mounted on the mast member spaced along at least a part of the length of the mast member to serve as a ladder. The step formations are characterised therein that at least some of them extend at least halfway about the mast member.

Description

TELECOMMUNICATION MAST

WITH LADDER ARRANGEMENT

This invention relates to telecommunication masts. More particularly the

invention relates to such masts which include a ladder arrangement mounted

thereto.

In this specification the term "telecommunication mast" is used to mean a mast

structure adapted to mount telecommunication means for receiving,

transmitting or relaying telecommunication signals such as radio or other

electro-magnetic wave signals.

Known telecommunication masts used in the cellular phone industry comprise

a hollow upright mast member with a spine of significantly reduced diameter

mounted to the operatively upper end of the hollow mast member.

Telecommunication means such as a number of antennae are mounted to the

spine and one or more ladders are provided between the antennae. This

arrangement makes it very difficult to alter the position of the antennae

relative to the spine since the position of the one or more ladders will restrict

such changes. According to the present invention there is provided a telecommunication

mast comprising an elongate mast member; and a plurality of step formations

mounted on the mast member spaced along at least a part of the length of the

mast member to serve as a ladder; and the step formations being characterised

therein that at least some of them extend at least halfway about the mast

member.

The mast member may comprise a hollow member, preferably a hollow

tubular member. The mast member may define a base and an operatively

upper extremity and the mast may taper from the base to the upper extremity.

The mast member may have a circular or polygonal cross-sectional

configuration, for example a 12- or 20-sided polygonal cross-sectional

configuration. The mast member may comprise a number of sections which

are in use secured to each other in an end to end relationship. Preferably the

sections fit into one another spigot and socket fashion.

Preferably the whole of the mast member is hollow and it does not include a

spine of reduced diameter mounted to the operatively upper extremity of the

mast member.

The mast member may include one or more access openings into the hollow mast member. Preferably the mast includes two access openings in the hollow

mast member, one provided at the base of the mast member and the other

provided towards the operatively upper extremity of the mast member.

Preferably a ladder is provided in the hollow mast member between the two

openings.

Closure means, such as a door may be provided for closing an access opening.

The mast member may be made of steel based plate material having a tensile

strength of more than 430MPa and a yield strength of more than 290MPa.

Preferably the mast member is made of steel based plate material which is

resistant to corrosion. The material may comprise high strength low-alloy

steel which is resistant to atmospheric corrosion. When these materials are

exposed to normal atmospheric conditions a tightly adhered oxide patina

normally forms on the exposed surface thereof, which very considerably

reduces the rate of further oxidation. Materials of this type may comprise the

materials known in the trade as BS4360 Grade WR50 and COR-TEN.

Preferably the material comprises COR-TEN.

The plurality of step formations may be provided towards the operatively upper end of the mast member.

Preferably a plurality and more preferably the majority of the step formations

extend at least halfway about the mast member. Preferably all the step

formations extend at least halfway about the mast member. Preferably the step

formations extend substantially fully about the mast member and preferably

they extend fully about the mast member. The step formations may comprise

ring-shaped members and preferably they extend in a spaced apart relationship

from the mast member about the mast member. One or more connecting

members may be provided to extend between each ring-shaped member and

the mast member. The ring-shaped members may be made of round bar.

The telecommunication mast may include further means mounted to the step

formations. The means may comprise telecommunication means for receiving,

transmitting or relaying telecommunication signals. In one embodiment it

comprises one or more antennae.

The further means may be directly mounted to at least some of the step

formations. Alternatively mounting brackets or the like are employed to

mount the further means to at least some of the step formations. A platform may also be provided towards the upper end of the mast member,

preferably just below the step formations.

The mast may also include means for disguising it in the form of a tree. The

disguising means may comprise one or more artificial branches extending from

the mast member. The disguising means may also include a covering for the

mast member to provide it with the appearance of a tree trunk. The covering

may be in the form of artificial bark.

Without thereby limiting the scope of the invention and by means of example

only, one embodiment thereof will now be further described with reference

to the accompanying drawings wherein:

Figure 1 is a side view of a telecommunication mast according to the

invention;

Figure 2 is a side view of the upper portion of the mast of Figure 1; and

Figure 3 is a plan view of the mast of Figure 2 sectioned through line EL-ITI.

In the accompanying drawings the same reference numerals are used to denote corresponding parts.

Referring now to the drawings a telecommunication mast 10 includes an

elongate tubular mast member 11 defining a base 12 and an operatively upper

extremity 13. The mast member 11 tapers from the base 12 to the upper

extremity 13. The mast member 11 includes four sections 11.1 which are

secured to each other spigot and socket formation as shown at 14 to form the

mast member 11. The mast member 11 has a 20-sided polygonal cross-sectional

configuration.

The whole of the mast member 11 is hollow and it does not include a spine

with reduced diameter mounted to the operatively upper extremity of the mast

member 11.

The mast member 11 includes two access openings 15 and 16 therein, one

opening 15 being provided at the base 12 and the other towards the operatively

upper extremity 13 but spaced therefrom. A ladder [not shown] is provided

in the hollow mast member 11 to allow a person to climb up the mast member

11. The openings 15 and 16 may be provided with doors [not shown] for

closing them. The mast member 11 is made of steel based plate material having a tensile

strength of more than 430MPa and a yield strength of more than 290MPa. The

plate material comprises a high strength low alloy steel known in the trade as

COR-TEN which is resistant to corrosion. The use of this material obviates

the need to galvanise or otherwise treat it to protect it against corrosion. It

will be appreciated that the mast member 11 may still be treated (e.g. painted

or galvanised) for aesthetic purposes, but from a corrosion prevention point of

view such treatment is not necessary. Masts manufactured from this material

are also lighter and less costly to manufacture.

The mast 10 also includes a ladder arrangement 17 provided at the upper

extremity of the mast member 11. The ladder arrangement 17 comprises a

number of step formations 18 mounted on the mast member 11 spaced along

the upper part of the said mast member 11. Each step formations 18 extends

fully about the mast member 11. Each step formation 18 comprises a ring

shaped member 19 [Figure 3] which extends about the mast member 11 in a

spaced apart relationship. Connecting members 20 are provided to extend

between each ring shaped member 19 and the mast member 11 to secure the

ring shaped member 19 to the mast member 11. The ring shaped members 19

are made of round bar. Telecommunication means such as antennae 21 are mounted to the step

formations 18. Since the step formations 18 extend about the mast member 11

they allow the antennae to be mounted in any position about the mast member

11 and still allowing the portions of the step formations 18 between the

antennae 21 to be used as a ladder. It is accordingly fairly easy to adjust the

position of the antennae 21 or other telecommunication means [not shown].

The antennae 21 are mounted via brackets 22 to elongate securing members 23

which in turn are secured to the step formations 18, by welding or otherwise.

By securing the antennae 21 or other telecommunication means to the hollow

mast member it is not required to provide a spine of reduced diameter for

mounting the telecommunication means thereto. By eliminating the use of

such a spine the problems associated with such a spine, namely fatigue at where

it is joined to the mast member 11 and increased labour for mounting it to the

mast member 11 is avoided.

A platform arrangement 24 to allow a person to stand on, is provided at the

upper extremity 13 but below the step formations 18.

The mast 10 also includes disguising means for disguising the mast 10 in the

form of a tree. The disguising means includes a number of branches 25 [only the lower parts of which are shown in order not to hide other features of the

invention]. Foliage 26 is also attached to the branches 25. The disguising

means may also include a covering [not shown] for the mast member 11 to

provide it with the appearance of a tree trunk. The covering may be in the

form of artificial bark. The branches, foliage and covering may be of the

conventional type which may be mounted or secured in the conventional way.

It will be appreciated that the disguising means renders the mast 10 more

attractive to the eye and renders it less conspicuous especially in urban areas.

It will be appreciated that many variations in detail are possible without

thereby departing from the scope and spirit of the invention.

Claims

1. A telecommunication mast comprising an elongate mast member; and a

plurality of step formations mounted on the mast member spaced along

at least a part of the length of the mast member to serve as a ladder; and

the step formations being characterised therein that at least some of them

extend at least halfway about the mast member.

2. The mast of claim 1 wherein the mast member comprises a hollow tubular

member.

3. The mast of claim 2 wherein the whole of the mast member is hollow and

it does not include a spine of reduced diameter mounted to the operatively

upper extremity of the mast member.

4. The mast of any one of the preceding claims wherein the mast member is

made of steel based plate material having a tensile strength of more than

430MPa and a yield strength of more than 290MPa.

5. The mast of any one of the preceding claims wherein the mast member is

made of COR-TEN.

6. The mast of any one of the preceding claims wherein the plurality of step

formations are provided towards the operatively upper end of the mast

member.

7. The mast of claim 6 wherein the majority of the step formations extend

at least halfway about the mast member.

8. The mast of either one of claims 6 or 7 wherein the step formations extend

fully about the mast member.

9. The mast of claim 8 wherein the step formations comprise ring-shaped

members which extend, in a spaced apart relationship from the mast

member, about the mast member.

10. The mast of claim 9 which includes connecting members extending

between each ring-shaped member and the mast member.

11. The mast of any one of the preceding claims which includes

telecommunication means for receiving, transmitting or relaying

telecommunication signals mounted to the step formations.

2. A telecommunication mast substantially as here in described with

reference to the accompanying drawings.