GB2408285A

GB2408285A - Self-contained extensible mobile access tower

Info

Publication number: GB2408285A
Application number: GB0326792A
Authority: GB
Inventors: John Timothy Stevens
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-11-17
Filing date: 2003-11-17
Publication date: 2005-05-25
Anticipated expiration: 2023-11-17
Also published as: GB0326792D0; GB2408285B

Abstract

A scaffold tower comprises a working platform G having folding handrails PQ, which is supported by a folding variable height structure which is mounted on a base frame A with adjustable legs at each corner, the structure and platform G being raised and lowered from the base. All of the components are permanently connected. The structure may be raised by straightening and locking hinged support legs BC/DE. Stability may be provided by inclined cross brace K. Potential energy gas struts S may assist erection. The base frame A may have wheels and outriggers. The working platform may have toe kick rails N. The structure may also have a hinged ladder which is locked in position by clamp M. The platform may be reached by a trap door. The structure preferably collapses completely as shown in figure 5.

Description

Background

Mobile access towers are used to provide a platform for safe working at heights. They consist of a variety of loose individual components slotted together by hand to form square or rectangular staging. Further components are used to brace the staging in the horizontal and vertical plane. Additional height is gained by repeating the process where by a second set of staging is mounted upon the first set. As more height is required the task of lifting individual components up to the elevated height becomes more laborious and time consuming.

Invention The main thrust of the invention is to provide a means of access at height, using a tower arrangement erected entirely from a compact, folded down structure, consisting of ladder components and braces all integrally connected.

Patent summary

This patent application seeks to demonstrate a system without loose individual components. This system is held together by articulated joints and is erected all at ground level, up to the required height. The effort of erecting the whole structure at ground level to its full height, in incremental steps, can be assisted by the incorporation of potential energy devices. As the working height is increased, the structure becomes self- supporting, rigid in the horizontal plane and locked in the vertical plane by means of a simple clamp. Stability is provided by integral outriggers and braked wheels. The working platform is protected with unfolded hand- rails locked in place with simple clamps.

Description

The folding tower consists of a base frame A on which are connected four vertical columns arranged in two pairs BC/DE to support the top frame F which in turn carries the working platform G with hand-rails.

Two vertical columns form a pair and are tied together by horizontal and parallel members J to form a ladder configuration. Each pair of columns or ladder is in tam tied together by an inclined cross brace. K Each pair of columns is interrupted at intervals to form a fulcrum joint at the intersection with the inclined cross brace node. Further interruptions occur mid-way between two nodes to form a folc fig hinge L in the ladder thus allowing it to fold down when not in use. The ladder column unfolds as the inclined cross brace is lifted and when vertical and straight is locked in position with a simple clamp. M The total height of the tower can be increased by the addition of more inclined cross braces and ladder sections The inclined cross braces with corresponding folding ladder sections are employed to give a series of incremental working platform heights. z

The working platform is constructed with toe kick rails N and located with in the depth of the toe kick rails are the folded down hand- rails. The hand- rails consist of two short end sets P folded flat and with each long set Q folded one above the other over the short end sets. When erected the hand rails are locked in place with simply clamps. R Out riggers and wheels are attached to the base frame to provide stability and mobility.

The inclined cross brace K may be arranged in one of two ways.

option I option 2 l Option one requires the ladder to fold between two inclined cross braces whist option two requires the ladder to be mounted with in the frame of the inclined cross braces so permitting a more compact arrangement H when folded. Both option are to be included in the design and used for different erected height Options and models.

Potential energy gas struts S can be incorporated into option one inclined cross brace to assist with the erection of higher level working platforms.

Claims

Claims I A self-contained mobile access tower having all components

permanently connected comprising a working platform surrounded by folding handrails, the platform being supported by a folding variable height structure which is mounted on a base frame with adjustable legs at each corner, the structure and platform being raised and lowered from the base.
2 A self-contained mobile access tower as claimed in claim I Wherein the height of the structure is raised by straightening and locking hinged jointed members in the vertical plane.
3 A self-contained mobile access tower as claimed by claim 1 or claim2 Wherein raising the structure can be assisted with kinetic energy.
4 A self-contained mobile access tower as claimed in claim 1 or claim 2 Wherein the structure is triangulated in the vertical plane by two fixed length members connected with the third member centrally hinge jointed and positioned in the vertical.
S A self-contained mobile access tower as claimed in claim 1 or claim2 or claim4 Wherein joining together of additional triangulated sections by a common member in the vertical plane increases the height.
6 A self-contained mobile access tower as claimed in claim 4 or claim 5 Wherein joining together triangulated members may be adjacently fixed horizontally or off set vertically.

7 A self- contained mobile access tower as claimed by claim I or claim 2 or claim 4 or claim 5 or claim 6 Wherein the structure is box shaped being formed by two vertical planes of triangulated members where each plane is joined together by horizontal members or the two vertical planes are arranged close together to form one plane positioned in the centre of the horizontal members.

X A sell:contained mobile access tower as claimed in any preceding claim wherein the platform is provided with a set of folding handrails 9 A self-contained mobile access tower as claimed by claim 8 Wherein the folding handrails reduce in size.

A self-contained mobile access tower as claimed by claim 7 or claim 8 wherein the handrails unfold and fasten together being restrained in the horizontal and vertical direction.

A self-contained access tower as described herein with reference to figures 1/2/3/4/5 of the accompanying drawings.

Amendments to the claims have been filed as follows 1. An access tower comprising two mutually spaced side parts extending from a base part to a top part, the side parts supporting the top part, and inclined cross parts each extending from one side part to the other, the inclined cross parts being arranged one above another and inclined in opposite senses, the inclined cross parts being rigid and being connected to the side parts, the lower of two successive inclined cross parts having its upper end connected to an articulation node to which the lower end of the upper of the said two successive inclined cross parts is connected, the section of the side part opposite the said articulation node, which section extends between the upper end of the upper cross part and the lower end of the lower cross part, being collapsible so that the upper cross part together with the portion of the tower above it can be lowered into a position in which the upper cross part extends substantially parallel to the lower cross part, releasable clamping means being provided to prevent collapse of the said collapsible section.

2. An access tower as claimed in claim 1, in which at least one of the side parts comprises columns which are mutually spaced in a direction transverse to the direction of mutual spacing of the side parts.

3. An access tower as claimed in claim 2, in which the columns are connected by rigid members.

4. An access tower as claimed in claim 3, in which the rigid members extend substantially horizontally.

5. An access tower as claimed in claim 4, in which the columns and rigid members 6. An access tower as claimed in any preceding claim, in which the said collapsible section is foldable about a hinge intermediate its upper and lower ends.
7. An access tower as claimed in claim 6, in which the upper and lower cross parts are of substantially equal length and the hinge is substantially mid-way along the collapsible section.
8. An access tower as claimed in claim 6 or 7, in which the collapsible section is foldable only inwards towards the said node.
9. An access tower as claimed in any of claims 6 to 8, in which the clamping means comprises a clamp associated with the hinge and movable from a position in which it prevents folding of the collapsible section about the hinge to a position in which it allows such folding.
10. An access tower as claimed in any preceding claim, in which each side part is articulated to the base part, the top part, and the inclined cross parts, the uppermost inclined cross part being articulated to the top part, and the lowermost inclined cross part being articulated to the base part.
11. An access tower as claimed in any preceding claim, in which each inclined cross part comprises a single inclined cross brace or a pair of equally inclined cross braces.
12. An access tower as claimed in claim 11, when dependent on claim 2, in which the single cross brace is positioned between two columns.
13. An access tower as claimed in claim 11, in which the cross braces of the pair are on the outsides of the two side parts.
14. An access tower as claimed in any preceding claim, in which there are more than two inclined cross parts.
15. An access tower as claimed in any preceding claim, in which the cross parts are inclined at an angle of less than 45 to the horizontal.
16. An access tower as claimed in any preceding claim, in which the top part comprises a working platform.
17. An access tower as claimed in claim 16, in which the working platform has handrails.
18. An access tower as claimed in claim 17, in which the handrails can be folded down and are held in place by releasable clamping means.
19. An access tower as claimed in any preceding claim, in which the base part has wheels.
20. An access tower as claimed in any preceding claim, in which the base part has outriggers.
21. An access tower as claimed in any preceding claim, including means for storing potential energy as the upper cross part is lowered towards the lower cross part and releasing stored potential energy to assist raising of the upper cross part.
22. An access tower as claimed in claim 21, in which the said means comprises a gas strut.
23. An access tower substantially as described with reference to, and as shown in, Figures l and 2 or Figures 3 and 4 of the accompanying drawings.