GB2553803A

GB2553803A - Access tower

Info

Publication number: GB2553803A
Application number: GB1615655.6A
Authority: GB
Inventors: John Moreby Mark; Stuart Wright Charles
Original assignee: Lakeside Industries Ltd
Current assignee: Lakeside Industries Ltd
Priority date: 2016-09-14
Filing date: 2016-09-14
Publication date: 2018-03-21
Also published as: GB201615655D0

Abstract

The access tower 1 is constructed from aluminium tubing 17 having a wall thickness of 3mm and has a fall arrest anchor 11 for attaching a releasable fastener of a fall arrest device. The anchor may be a bracket in the form of a plate with an aperture 25 therethrough and be attached at an intersection between a horizontal tube and a vertical tube of the tower. The anchor may have feet in the form of flanges 26, 27 . The anchor may be made of stainless steel. The access tower is for example a scaffold with a safety anchor to prevent falling from height. The tower may have cast connecting elements welded to the tubes to allow frameworks to be connected end to end.

Description

(71) Applicant(s):

Lakeside Industries Limited (Incorporated in the United Kingdom)

Unit 19 Howard Road, REDDITCH, Worcestershire, B98 7SE, United Kingdom (72) Inventor(s):

Mark John Moreby Charles Stuart Wright (56) Documents Cited:

GB 2392950 A CA 002638490 A1 US 5361866 A JPS62186757

GB 2142701 A JP 2001107552 A (58) Field of Search:

INT CLA62B, E04G Other: Online: WPI, EPODOC (74) Agent and/or Address for Service:

Albright IP Limited

County House, Bayshill Road, CHELTENHAM, Gloucestershire, GL50 3BA, United Kingdom (54) Title of the Invention: Access tower

Abstract Title: Access tower including fall arrest anchor (57) The access tower 1 is constructed from aluminium tubing 17 having a wall thickness of 3mm and has a fall arrest anchor 11 for attaching a releasable fastener of a fall arrest device. The anchor may be a bracket in the form of a plate with an aperture 25 therethrough and be attached at an intersection between a horizontal tube and a vertical tube of the tower. The anchor may have feet in the form of flanges 26, 27 . The anchor may be made of stainless steel. The access tower is for example a scaffold with a safety anchor to prevent falling from height. The tower may have cast connecting elements welded to the tubes to allow frameworks to be connected end to end.

Figure 3

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Figure 4

Figure 3

ACCESS TOWER

The present invention relates to an access tower including a fall arrest anchor point.

BACKGROUND TO THE INVENTION

There are many tasks in industry for which an operative may need to work at height. Aluminium access towers have been in use for a long time to enable an operative to work at height. An access tower is a quick assembly and disassembly tower structure supporting a platform on which operatives may work. Access towers comprise rigid frameworks of horizontal and vertical aluminium tubing that can be connected together end to end by connector units to form a side of the tower. Two sides of the tower formed by these connected framework arrangements can then be joined by struts, the struts forming the two remaining sides of the tower. The struts can be attached in horizontal or diagonal configurations to provide structural reinforcement. Corner spars are attached to this structure to provide stability. Support platforms also connect between the tower sides.

Falls from height are one of the most prevalent causes of industrial injury. Conventionally the only means of fall restraint on aluminium access towers is provided by a handrail and/or kickboard and no means of fall arrest protection is provided.

During the process of building a conventional aluminium access tower there is a stage at which the working platform is not complete and has no guard rails. This may be dangerous because operatives may be working at height while building the tower and may fall and sustain an injury. Conventionally the assembly of the scaffold is carried out by the ‘through the trap method’ or by the use of an advanced guard rail, to minimise this risk. Although both methods give a degree of protection, because the operative has some form of barrier around him whilst adding frames or platforms, and braces and handrails above himself, that barrier being either the trapdoor or the advanced guardrail unit, there is still a risk of falling. Additionally, advanced guard rails are heavy and cumbersome to manipulate and bring their own risks in use.

It is known in the fields of conventional steel scaffolding and powered access devices to provide a means of fall arrest such as a harness which is attached to the operative and a fall arrest anchor point to which the means of fall arrest is attached. However aluminium access towers are not strong enough to support a known fall arrest anchor and may fail in the event of a fall.

It is an object of the present invention to reduce or substantially obviate the aforementioned problems and thus to increase the safety of operatives working at height using access towers.

STATEMENT OF INVENTION

According to the present invention, there is provided an access tower constructed from aluminium tubing, the aluminium tubing having a wall thickness of at least 3mm, and including a fall arrest anchor for attaching a releasable fastener of a fall arrest device.

The tubing being made of aluminium confers the advantage of a lower weight than could be achieved with steel, and the aluminium tubing having a wall thickness of at least 3mm ensures that the structure of the tower has the necessary strength to support the fall arrest anchor in the event of an operative’s fall being arrested. The releasable fastener may be a carabiner or another releasable clip device.

This allows operatives to work on the tower safely and to assemble the tower using the advanced guard rail method or the through the trap method, whilst being safely restrained by a fall arrest system. It is expected in the future that it may be possible to assemble access towers without the use of an advanced guard rail or the through the trap method by virtue of the present invention.

Preferably, the fall arrest anchor is rigidly affixed to the aluminium tubing with fixings, allowing the impact of an operative’s fall being arrested to be transmitted to the aluminium tubing.

The fixings may be bolts or rivets, preferably high performance fixings, which can withstand the forces exerted by an operative’s fall being arrested.

The access tower may be constructed from a plurality of frameworks and connecting struts, the frameworks each including vertical and horizontal aluminium tubes fully welded together at their intersections. The frameworks are preferably connected together end to end to form a side of the tower. Two sides of the tower formed by these connected framework arrangements can then be joined by the connecting struts, the struts forming the two remaining sides of the tower. The struts can be attached in horizontal or diagonal configurations to provide structural reinforcement. The horizontal and vertical aluminium tubes of the frameworks are fully welded together at their intersections to increase the strength of the tower compared to other fixing means, in order to ensure that the frameworks have the necessary strength to support the fall arrest anchor in the event of an operative’s fall being arrested. The fall arrest anchor is preferably connected to a framework of the tower.

The access tower may include cast connecting elements welded to the frameworks for connecting them together end to end. The joins between the cast connecting elements and the frameworks may be fully welded to provide additional strength.

The fall arrest anchor may be affixed between a vertical aluminium tube and a horizontal aluminium tube, the vertical and horizontal tubes being fully welded together at their intersection. For example, the fall arrest anchor may be affixed across a corner of a framework. This configuration is preferred as it confers additional strength to the access tower, as the fall arrest anchor is thus supported by the aluminium tubing at a point of enhanced strength, the enhanced strength being provided by the proximity of the fully welded join.

The fall arrest anchor may be formed as a bracket comprising a body having an aperture there-through, and feet provided at each end of the body affixed to the aluminium tubing. The aperture allows convenient attachment of a means of fall arrest such as a harness, via a releasable fastener such as a carabiner or another releasable clip device. The feet of the fall arrest anchor provide a point for the attachment of the aforementioned fixings, and allow the fall arrest anchor to be attached to the aluminium tubing in an optimal arrangement.

The feet may be provided by first and second flanges. The flanges enable positioning and convenient fixing of the fall arrest anchor.

The body of the fall arrest anchor may be made from a plate, with the aperture being cut from a central area of the plate to leave a rear spar member and a front member. The manufacturing of the fall arrest anchor from a plate both minimises the cost and time of production and confers greater structural integrity and strength to the fall arrest anchor than otherwise may be achieved. The rear spar member and the front member provide points for the attachment of a means of fall arrest such as a harness, via a releasable fastener such as a carabiner or another releasable clip device.

The plate may have an external face and an internal face, the flanges extending to the internal face side of the plate.

The flanges may be affixed across a diameter of the aluminium tubing, the external face lying towards an outer side of the access tower. The flanges may be butted up to an inner face of the tower frame horizontal and vertical elements. This arrangement allows the fall arrest anchor to be attached to the aluminium tubing in such a configuration that a means of fall arrest may be attached at a location convenient for the working of an operative.

The fall arrest anchor may be made from mild steel or carbon fibre, though preferably it is made from stainless steel.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made by way of example only to the accompanying drawings, in which:

Figure 1 shows a perspective view of an access tower;

Figure 2 shows a perspective view of a framework in isolation;

Figure 3 shows a partial side view of a framework with a fall arrest anchor point; and

Figure 4 shows a cross sectional view through a part of the fall arrest anchor and the vertical aluminium tube taken along direction I indicated in figure 3.

Referring firstly to Figure 1, a first embodiment of an access tower including a fall arrest anchor is indicated generally at 10 in perspective view.

The access tower is constructed from a plurality of frameworks 13, one of which is shown in figure 2, and connecting struts 14, 15. The frameworks each including vertical and horizontal aluminium tubes 17, 18. The tubes are fully welded together at their intersections, i.e. the weld extends around the entire joint. The frameworks 13 are connected together end to end to form a side of the tower. Two sides of the tower formed by these connected framework arrangements are joined by the connecting struts 14, 15, the struts forming the two remaining sides of the tower. The struts can be attached in a horizontal configuration 14 and a diagonal configuration 15 to provide stability by triangulation.

The access tower includes cast connecting elements 16 welded to the frameworks 13 for connecting them together end to end. The cast connecting elements are fully welded to the frameworks. The fall arrest anchor 11 is affixed between a vertical aluminium tube 17 and a horizontal aluminium tube 18, the vertical and horizontal tubes being fully welded together at their intersection. In the embodiment shown, the fall arrest anchor is affixed across a comer of a framework 13, for example an outside comer, at the top of the tower.

Figure 2 shows a perspective view of a framework 13 in isolation with a fall arrest anchor 11 attached to it. The framework includes vertical aluminium tubes 17 and horizontal aluminium tubes 18. These tubes are fully welded together at their intersections 21. Figure 2 also shows cast connecting elements 16 welded to the framework for connecting it to another framework end to end. The joins between the cast connecting elements and the framework are fully welded to provide additional strength. The fall arrest anchor 11 is affixed between one of the vertical aluminium tubes 17 and one of the horizontal aluminium tubes 18 across the fully welded join between the tubes 21.

Figure 3 shows a side view of a fall arrest anchor 11 fixed to a framework 13 (part shown). The fall arrest anchor is rigidly affixed to the aluminium tubing with fixings 23. The fixings 23 are bolts, however rivets or screws can be utilised, ideally all of a high performance nature. The framework 13 includes a vertical aluminium tube 17 and a horizontal aluminium tube 18 fully welded together at their intersection 21. The fall arrest anchor 11 is attached across the comer formed by the intersection of these tubes. The fall arrest anchor 11 is formed as a bracket comprising a body 24 having an aperture 25 there-through, and feet 26, 27 provided at each end of the body 24 affixed to the aluminium tubing. The feet are provided by a first flange 26 and a second flange 27. The body of the fall arrest anchor is made from a plate, for example stainless steel of thickness 4mm, with the aperture 25 being cut from a central area of the plate to leave a rear spar member 28 and a front member 29.

In a typical example, the feet 26, 27 are attached within 110mm of the corner of the joint of the aluminium tubes, in one example the width of the rear spar member 28 is 20mm and in another example the width of the front member 29 is 25mm. The thickness of the members 28, 29 is preferably no less than 4mm, but could be thicker, for example 5mm in thickness. It will be appreciated that these dimensions are suitable for use together or in combination with other dimensions. The front and rear spars need to be of a size to permit attachment of a standard climbing carabiner in use and the device needs to be of sufficient strength to arrest a fall from the tower successfully.

Figure 4 shows a cross sectional view through a part of the fall arrest anchor 11 and the vertical aluminium tube 17 taken along direction I indicated in figure 3. The fall arrest anchor has an external face 30 and an internal face 31, the flange extending to the internal face side of the plate 31. The flange is affixed across a diameter of the aluminium tubing, so that the fixings are normal to the surface of the tubing, the external face 30 lying towards an outer side of the access tower.

The embodiment described above is provided by way of example only, and various changes and modifications will be apparent to persons skilled in the art without departing from the scope of the present invention as defined by the appended claims.

Claims

1. An access tower constructed from aluminium tubing, the aluminium tubing having a wall thickness of at least 3mm, and including a fall arrest anchor for attaching a releasable fastener of a fall arrest device.

2. An access tower as claimed in claim 1, in which said fall arrest anchor is rigidly affixed to said aluminium tubing with fixings.

3. An access tower as claimed in claim 2, in which said fixings are bolts or rivets.

4. An access tower as claimed in claim 1, in which the access tower is constructed from a plurality of frameworks and connecting struts, the frameworks each including vertical and horizontal aluminium tubes fully welded together at their intersections.

5. An access tower as claimed in claim 4, in which cast connecting elements are welded to the frameworks for connecting them together end to end.

6. An access tower as claimed in any preceding claim, in which the fall arrest anchor is affixed between a vertical aluminium tube and a horizontal aluminium tube, the vertical and horizontal tubes being fully welded together at their intersection.

7. An access tower as claimed in any preceding claim, wherein said fall arrest anchor is formed as a bracket comprising a body having an aperture there-through, and feet provided at each end of the body affixed to the aluminium tubing.

8. An access tower as claimed in claim 7, in which the feet are provided by first and second flanges.

9. An access tower as claimed in claim 8, in which the body of the fall arrest anchor is made from a plate, with the aperture being cut from a central area of the plate to leave a rear spar member and a front member.

10. An access tower in which the plate has an external face and an internal face, the flanges extending to the internal face side of the plate.

11. An access tower as claimed in claim 10 in which the flanges are affixed across a 5 diameter of the aluminium tubing, the external face lying towards an outer side of the access tower.

12. An access tower as claimed in any preceding claim, in which the fall arrest anchor is made from stainless steel.

13. An access tower substantially as described herein, with reference to and as illustrated in Figures 1 to 4 of the accompanying drawings.

Intellectual

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Application No: Claims searched:

GB1615655.6

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