NZ616096B2 - Suspended scaffolding system - Google Patents

Abstract

suspended scaffolding system (100) including a connector system (112) adapted to engage a fixture (120), the fixture in use is in contact with a surface of a structure (30), an arm (114) connects the suspended scaffolding system to the connector system so that in use the suspended scaffolding system is suspended below the structure, characterised in that at least one moveable counterweight (142) is provided on the suspended scaffolding system, which is adapted to be displaced from a first position to a second position so as to change of the centre of gravity of the suspended scaffolding system. em is suspended below the structure, characterised in that at least one moveable counterweight (142) is provided on the suspended scaffolding system, which is adapted to be displaced from a first position to a second position so as to change of the centre of gravity of the suspended scaffolding system.

Description

PCT/IB2012/OS1092 SUSPENDED SCAFFOLDING SYSTEM Field of the Invention This invention s to a lding system. Particularly, but not exclusively, the invention relates to a suspended scaffolding system, for example of the type for use in the construction, inspection and maintenance of structures, in ular spanning structures.

Although reference has been made to spanning structures, it is understood that the ion may be used in the construction, inspection and maintenance of many other different types of structures such as: buildings, tunnels, elevated roadways, walkways, aqueducts, and other similar civil engineering undertakings.

Background of the Invention Many different structures span across a distance of for example, ten or more metres, including bridges and viaducts. These structures require temporary access from beneath during construction, inspection and nance routines, r access can be difficult. One method of access is to build a temporary scaffold from the ground up but this is unfeasible in many circumstances. Another method is to build a walkway or gantry whilst the ure is being built, however this increases costs at that stage, requires foresight and also may require security to prevent unauthorised access of the gantry.

It has ore been ised for a long time that a temporary structure, that is cheap and easy to deploy; is adaptable to a variety of different locations and situations; and which is safe and easy to use is wanted for construction, inspection and maintenance.

Prior Art US Patent Application 415431 and French Patent 2845715 disclose the use of a mobile suspended scaffold which is mounted onto a vehicle. The vehicle is driven along a bridge enabling work or Inspection. If there are obstacles along the edge of the bridge the whole scaffold must be retracted and repositioned making it awkward to use in some circumstances. Some existing scaffolding systems are a suspended type ones (PERI type), but they have supporting and izing elements as beams, frames or portal frames mounted on the upper e of the structure/bridge resulting in blocking or restricting of this space use for other purposes whilst the scaffolding is present.

An object of the invention is to overcome problems ated with aforementioned construction, inspection and nance systems by providing a single system that is le for a variety of different structures, which is physically able to be re-arranged to suit different applications and that is simple and cheap to use and is readily deployed and most importantly safe. No prior art arrangements achieve simple and effective stabilization of the suspended object in relation to the solid structure by the method described in this invention.

Summary of the Invention According to the present invention there is provided a suspended scaffolding system which includes a tor system adapted to engage a fixture, the fixture in use is in contact with a surface of a ure, an arm connects the suspended lding system to the connector system, so that in use the suspended scaffolding system is suspended below the structure, PCT/D82012/051092 characterised in that, the connector system has connectors that permit relative movement with respect to the fixture in two onal planes.

Preferably, relative movement is permitted with t to the fixture in three orthogonal planes.

Thus, according to this aspect of the invention, the scaffolding system is able to move laterally (from side to side). This lateral motion is achieved by way of the connector. Preferably, the connector ses a spherical device supported within a tubular device, but other solutions, for example as Cardan mount, can be used. In a preferred embodiment, the connector includes a spherical bearing. The connector may comprise a universal connector.

Alternatively, the connector includes a ball and socket device.

It is preferred that the fixture comprises a track along which the lding system can run. This enables the scaffolding system to move both laterally (from side to side) and forwards and backwards.

Rapid, safe and easy motion of the scaffolding system, lengthwise along the bridge or structure, is important as the quicker and easier it is able to transport equipment and personnel to a desired location the better this is. However, when reaching a specific position, it is important that the suspended scaffolding system is able to be placed into a relatively stable and nary state so that crew using it can work on the structure safely and without undue movement in the suspended scaffolding . Prior art generally requires elaborate g and the deployment of safety ent so that this could occur. Deployment and val of the locking and safety equipment took time and so reduced productivity.

According to a second aspect of the invention there is provided a ded scaffolding system including a connector system adapted to engage a fixture, the fixture in use is in contact with a surface of a structure, an arm connects the suspended scaffolding system to the connector system so that in use the suspended scaffolding system is suspended below the structure, characterised in that at least one moveable counten/veight is provided on the ded scaffolding system, which is adapted to be displaced from a -first position to a second position so as to change the centre of gravity of the suspended scaffolding system.

The invention provides an alternate manner of providing movable scaffolding for a structure by utilising a counterweight to ize a suspended movable scaffolding, having adaptable geometry, easily stabilized, lockable and equally easily releasable during the process of work carried out, able b overcome obstacles structurally present in the main structure without using large areas of the upper surface of the ure for mounting support elements.

The lding is suspended from a fixture which preferably comprises a rail, either on the top of the main structure, its edge or underside. If the rail and a cooperating carriage system on the scaffolding system is used as the attachment, the working platform and the scaffolding can move as work progresses along the ure.

A further object of the invention is to provide a ded scaffolding system having a support positioned on one or more of the upper, side and/or lower e of a structure whereby a counterweight movable between two positions moves the suspended scaffolding system's centre of gravity thereby ing a pushing force for stabilizing the equipment in a g position against main firm structure or object (building, , slab, terrace or cliff, rock, cave, ship etc.).

Thus the nt of the counterweight changes the position of the centre of gravity of the system by producing an acting force that pushes the suspended scaffolding against the main stable ure and in that way izes scaffolding position.

Preferably, a hydraulic jack powered by a motor is provided to displace the counterweight. Alternatively or additionally a hand crank is provided to displace the counterweight. Another system of cing the counterweight can be introduced, electric or pneumatic jack for example, or even manually operated one such as a chain winch or pulley. The person skilled in the art will iate which alternative embodiments are suitable for use with the system.

According to a third aspect of the invention there is provided a suspended scaffolding system which includes a track connector system adapted to engage a track, the track in use is in contact with the surface of a structure, characterised in that the track connector system ses at least three fasteners each of which is in t with the track and each is adapted to be temporarily removed from the track, when encountering an obstacle, so as to permit the suspended scaffolding system to negotiate the obstacle or to move into a new position.

According to a fourth aspect is a method of moving a scaffolding system which is movable along a rail, the rail being fixed to a surface by at least one fastener comprising the steps of: providing a further er to fix the rail to a structure; removing one of the at least one fasteners to enable the scaffolding system to progress its' movement; and optionally replacing the removed fastener once the scaffolding system has progressed its' movement.

The fastener can be removed from the rail entirely or pivoted out of the way.

This arrangement enables the scaffolding system to be used along the entire length of a structure, straight or , which is for example a bridge, on a PCT/D82012/051092 rail, runner or section of a rail or runner. Sections of rail or runner may be d and placed ahead of r section. in a red embodiment, the suspended lding system includes a suspended working platform (SWP™) and a safety rails disposed around a periphery of the working platform.

Traditionally, in this type of system, reaction bearings or end stops are used to prevent the scaffolding system overrunning and either becoming completely dislodged from the rail or causing damage to the connector of the lding system. However, the fact that end stops are used means that these have to be d when a new rail section is added which is time consuming and requires extra parts. in the present invention, it is preferred that a rail end automated blocking device, designed within the rail itself, is used which are active if the rail segment is the end one, but which is de-activated by the connection on the next rail segment. This has the added safety advantage that a worker does not have to remember to add an end piece during construction; each rail has an end piece integral to it.

According to another aspect of the invention, there is provided a method of stabilizing a suspended structure sing the steps of: providing a suspended structure; and adjusting the suspended structures' centre of gravity away from a neutral position thereby producing a stabilizing force.

Preferably, the adjustment of the suspended structures' centre of gravity is achieved by one or more of counterweight nt, ballasting and swinging. Example include moving a mass element (sliding, swinging, rotating, pumping ballast from tank to tank) or by adding or removing mass m the object (filling / emptying ballasting tanks). in a preferred ment, the stabilizing force is transferred to a supporting structure using a bumper.

Preferably, there is provided one fixed suspension point located on the upper, side or lower edge/surface of the structure and at least two s of the suspended object in contact with the structure, giving in total three points of stabilization of the suspended object on.

In a preferred embodiment, there are ed two fixed suspension points located on the upper, side or lower edge/surface of the structure and at least one bumper of the suspended object in contact with the structure, giving in total at least three points of stabilization of the suspended object position.

Adjusting the centre of gravity by deployment of for e a counterweight, the centre of gravity of the scaffolding system is shifted from a first location, at which the scaffolding system hangs freely on one or more fixing points and is able to move , for example by running along a rail, to a second location in which the scaffolding system is urged against the structure so that the scaffolding system is held in a relatively fixed position with at least two points in contact with a rail or runner and at least one, the third point in t with the structure, which as a result of a reaction force ensure that the scaffolding system remains stationary, but which can be moved to a different location relatively y and easily, even by personnel who are on board a working platform supported by the scaffolding.

Preferably the third point of contact is by way of a friction pad or buffer / bumper.

Preferably, the suspended scaffolding system comprises a contact point, with the structure, includes a reaction bearing roller.

Therefore, it is an object of the invention to provide the technical ization method of the suspending objects/technical equipment in relation to the main stable outer structure by using the adjustable and lockable rweight as part of the suspended object and by this counterweight intentional displacement inducting pushing/locking force izing the suspended object to the main structure.

When using movable and adjustable counterweight and bumper/buffer system the SSS - Suspended lding System do not requires any additional top surface level or under surface level cooperation or support except own one.

When the movable and adjustable counterweight is engaged it pushes the SWP -Suspended Working Platform towards the bridge/structure locking it into position. When the counterweight is disengaged, there is no pushing and no contact with the bridge/structure and the SWP can be easily moved/passed, to the new working area.

The SSS- Suspended Scaffolding System is more cal and cost-effective solution, than the tly used ones: top support mounted frames with suspended arms; trailer under bridge inspection units; lower level surface mounted up scaffolding for the structure above. The invention is presented here (as particular example, not excluding other different applications) as the mode to construct the suspended lding with working platform (SWP) for ng the maintenance or structural work from underneath the bridge/structure without using the constructing extended scaffolding structures on the top of the bridge as support for the d down scaffolding towers with ded on the underside working platforms. The SSS solution saves time and money, as well g upper bridge/structure surface freely accessible for other stages of construction work or the standard uninterrupted and not distracted use.

The invention will now be described, by way of example, with reference to the accompanying drawings: in which:- Brief Description of the Drawings Figure 1 is a diagram of the technical stabilizing device and main acting forces scheme showing a suspended object in free hanging and moveable position, for the option of upper surface fixing to the main structure; Figure 2 is a diagram of the technical stabilizing device and main acting forces scheme showing a suspended object in working position, for the option of upper e fixing to the main structure; Figure 3 is a diagram of the technical izing device and main acting forces scheme g a suspended object in free hanging and moveable position, for the option of underside surface fixing to the main structure; Figure 4 is a diagram of the cal stabilizing device and main acting forces scheme showing a suspended object in working on, for the option of underside surface fixing to the main structure; Figure 5 is a diagram of the technical stabilizing device and main acting forces scheme showing a suspended object in free hanging and moveable position, for the option of side surface fixing to the main ure; Figure 8 is a diagram of the technical stabilizing device and main acting forces scheme showing a ded object in working position, for the option of side surface fixing to the main structure: Figure 7 is a diagram of the technical stabilizing device and main acting forces scheme showing a suspended object in free hanging and moveable position, for the option of slot upper surface fixing to the main structure; Figure 8 is a diagram of the cal stabilizing device and main acting forces scheme showing a suspended object in working position, for the option of slot upper surface fixing to the main structure; Figure 9 is a diagram of the technical stabilizing device and main acting forces scheme g a suspended object in free hanging and moveable position, for the option of underside interna! surface fixing to the main structure; Figure 10 is a diagram of the technical stabilizing device and main acting forces scheme showing suspended object in working position - stabilized according to the ion, for the option of underside internal surface fixing to the main ure; Figure 11 is a perspective of a frame (SWP - Suspended Working Platform) for a ded scaffolding system according to the invention; Figure 12 is a perspective of an attachment system for attaching a frame (SWPTM -Suspended g Platform) to a rail; Figure 13 is a perspective of a counterweight system according to the invention; Figure 14 is a perspective of a counterweight system in free hanging position; Figure 15 is a cross section through a rail and carriage truck; Figure 16 is a ctive of a suspended scaffolding system according to the invention (with standard scaffolding system inflll used to create safe working environment); Figure 17 is an alternate perspective view of a suspended scaffolding system; Figure 18 is a transverse view of a suspended scaffolding ; Figure 19 is a transverse view of a suspended scaffolding system in free hanging position; and Figure 20 is a transverse view of a suspended scaffolding system in fixed or working position.

Detailed Description of the illustrated embodiment Figures 1 to 10 illustrate some general usage ios of a device according to the invention providing suspended objects stabilization by pushing them to main stable structure 30 by using force from moving the suspended object's centre of gravity 38 away from its l position. The centre of gravity 38 movement is caused by position adjustment of counterweight 37 component of the device.

Each of figures 1 to 10 show (in different configurations, ng and usage scenarios) the same elements of the invented stabilization method: the structure 30 (building, bridge, slab, and terrace, ....) to be accessed for carrying the work from beneath 2|9 structure 30. There are three main parts, the attachment system 31 ,32,33 of the suspended objecVscaffolding which is the connection to the structure 30, a suspended objecV suspended working platform 34,35,38,37,39; and additional features such as scaffolding 40, 41, 42. The attachment system 3 1,32,33 comprises a e including one or more fixing points or a rail 3.1, temporarily or permanently ed to the structure 30.

For applications in which the ded object is movable along the length of the structure, a rail 3 1 is provided for attachment to the structure 30 and one, WO 20471 PCT/B82012/051092 two or more independent carriage/truck sets 32 are provided which roll within the rail 31 connected via a pin mounted in a g 33 at the end of the ded objecVsuspended working platform beam or arm 34,39.

The fixing system includes a spherical bearing 33 or Cardan mount or any other g solution allowing rotation in any plane. The suspended suspended working platform frame is represented here by the suspended objecVsuspended working platform beam or arm 39 (Figures 1 and 2 only), vertical mounted down arm/frame 34, and a horizontal g part of the platform 35, with adjustable (angle and length) bumpers/buffers end 36. The use of the platform 35 as a working environment would require optional add-in for example: allowing access horizontal platform 40 - any scaffolding system or other, scaffolding stair tower access 41 - any scaffolding system or other, lower working level horizontal rm 42 with side bars - any scaffolding orformwork system.

The whole suspended objecV suspended working platform 36,37,39 in a free g position (figures 1,3,5,7,9) is hanging freely on two or only one support points 31 vulnerable for example for the wind pressure, not stabilized, even free swinging, with the possibility of hitting the ure 30 if prevention measures are not taken t that (i.e. Dumpers can be used to reduce swinging caused by wind).

In examples where the support points 31 are provided on a rail, in this configuration - hanging freely ~ the suspended object is easily movable along the length of the structure and can pass obstacles.

The suspended working platform 34,35,36,37,39 comprises suspended objecVsuspended working platform beam or arm 39 through which the suspended object is attached to the structure 30, vertical side frames 34, a horizontal frame of working platform 35 and bumpers/buffers 36 for abutment to the underside 29 of the structure 30. The angle and length of the bumpers and s 38 are able according to need. In the free hanging position (Figures 1,3,5,7,9) there is no contact of s/buffers 36 with the main structure 30.

The stabilization effect of the free hanging object to the main outer structure is achieved by adding a counterweight 37, to the suspended object/scaffolding, and adjusting this counterweight's position. The counterweight can be moved and locked in different ons in relation to the suspended object/scaffolding, for example by the use of rails and hydraulic jack).

When the centre of gravity 38 of the whole hanging structure (suspended working platform 34,35,36,39 and counterweight 37 and possibly workers, equipment and materials as well as add-on accessories) is in a neutral position, it lies within a strictly vertical plane B below the upper attachment poinVpoints 31, then the whole structure is hanging freely - like the scheme pictured on Figures 7 and 9.

When the counterweight part 37 of the whole suspended working platform 34,35,36,39 is intentionally repositioned in direction C opposite the main outer structure location 30 i.e. away from the centre of the structure 30 or towards an outer edge of the structure 30, then the centre of y 38 of the whole structure (suspended working platform 34,35,36,39 and rweight 37 and possible workers, equipment and materials as well as add-on accessories) is moved off its neutral position - like the schemes pictured in Figures 2,4,6,8 and 10.

In this position, the main acting force- the gravity, is forcing the shifted centre of gravity 38 back towards neutral position which is exactly within a strictly vertical plane below the upper attachment poinVpoints 31. However, this movement is prevented by the bumpers/buffers, that indicated force F3 52 is then -transferred into the structure 30 via bumpers/buffers 36, and the passive resistance of the structure 30 gives the stability to the whole equipment. The ded objecV suspended working platform s then in the ized, locked-in, working position, as pictured in Figures 8 and 10.

Note: the forces diagrams of Figures 1 to 10, show only main al forces acting 50,51 ,52 and 53 on the components; where F1 force 50 is a vertical component of reaction force on the main structure 30 in the place of upper supporting/fixing point/points or rail; F2 force 51 is a gravity force of the whole suspended object; F3 force 52 and/or F4 force 53 is/are present only for locked-in stabilized position (Figures 2,4,6,8 and 10), as a vertical component or reaction force, when the suspended object/suspended working platform 34,35,36 is locked in working position by counterweight 37 displacement and passive resistance on the base structure 30 es a brace.

In the free hanging position of the suspended object (Figures 1,3,5,7 and 9) the F2 acting gravity force 51 is lined up with the F1 re-acting force 50 of the supporting main structure 30, and the system is in equilibrium. In the locked- in stabilized position (Figures 2,4,6,8 and 10) the F2 acting gravity force 51 is displaced from the line of the F1 ing force 50 of the supporting main structure 30, and the system has a ntal component reaction force forcing the shifted centre of gravity 38 towards it neutral position strictly under the attachment poinVpoints 31 to the main structure 30. The other component forces (horizontal) would be: wind re and horizontal component force of F3 reaction 53, as the bumper 36 pushes on the angled surface of main structure 30. All horizontal forces would be transmitted onto the structure 30 via the attachment system 3 1,32,33 and bumpers 36. s 1,3,5 show the ms of the technical stabilizing device and main vertical components of acting forces 50,51 scheme showing suspended object (example: Suspended Working rm -SWP) 34,35,36,39 in free hanging and moveable/passabie position, respectively for the options of upper, underside and side surface fixing to the main structure 30. In the free hanging position of the suspended working platform 34,35,36,39 the counterweight 37 is used as a member to balance required geometry of the whole equipment (for example when in the process of moving from one to the other work location along the structure). The counterweight 37 position is to be ed ly or mechanically, ed from the working platform 35 or ere by remote control.

Figures 2,4,8 show the diagrams of the technical izing device and main al components of acting forces 50,51 ,52 scheme showing suspended object (example: ded Working Platform -SWP) 34,35,36,39 In stabilized, locked-in for work position, respectively for the options of upper, underside and side surface fixing to the main structure. In the locked-in, secured and stabilized working position of suspended working platform 34,35,36,39 the counterweight 37 is acting as a member generating the pushing/locking force, bracing the suspended object 34,35,36,39 to the main structure 30. The repositioned and lockable counterweight 37 shifts the centre of gravity off its neutral position and acts here as the member generating the pushing/locking force on one or two bumpers ends 36 from the re-action of the structure 30, providing the required safe and stable working environment. s 7,8 show the diagrams of the technical stabilizing device and main vertical components of acting forces 50,51 ,52,53 ; showing suspended object (example: Suspended Working Platform -SWP) 34,35,36 respectively in free hanging, moveabie/passable position (Fig.7) and working on (Fig. 8) for the option of t, upper surface fixing to the main structure 30, when the suspended working platform 34,35,36 is beneath the twin/mirrored main structures 30 or beneath the main structure 30 with a slot, and the suspended working platform 34,35,36 is canti levered, serving both sides underneath the structures 30; The counterweight 37 is acting here as a e stabilizer for the total weight of workers, the suspended working platform, als and equipment, and (using counterweight 37 adjustable position) as the member generating the g/locking force on one of two bumpers ends 36 from the re-action of the structure 30, providing the required safe and stable working environment.

Figures 9,10 show the diagrams of the technical izing device and main vertical components of acting forces 50,51 ,52,53 scheme; showing suspended object (example: Suspended Working Platform -SWP) 34,35,36 respectively in free hanging, moveable/passable position (Fig.9) and working position (Fig.10) for the option of internal ide surface fixing to the main ure 30 (for example bridge of this specific geometry cross section, or cave), when the ded working platform 34,35,36 is beneath the main structure 30, and the suspended working platform 34,35,36 is cantilevered, serving both sides eath the structure 30; The counterweight 37 is acting here as a balance stabilizer for the total weight of workers, the suspended working platform, materials and equipment, and (using counterweight 37 able on) as the member ting the pushing/locking force on one of two bumpers ends 36 from the re-action of the structure 30, providing the required safe and stable working environment.

When the working platform is in the free hanging position (not stabilized, locked-in) the rweight should be placed in such equilibrium position that neither of bumper ends 36 should be in contact with the structure. s 11 to 20 show various aspects of an embodiment of this invention: the SWP™ - Suspended Working Platform forming part of the SS8™ - Suspended Scaffolding System.

Figure 11 shows a frame 110,1 11 for a suspended working platform 100 of suspended scaffolding system and a rail or track 120 onto which the frame 110,1 11 is mounted.

The rail 120 is secured to a structure 30, such as a bridge, using spaced apart distance supporting pads 126 (see Figure 18) underneath the rail 120 and rail fasteners/clamps 122 which can bridge over the rail 120 if needed. The rail 120 has a guideway 124 running longitudinally along its' length into which a carriage/truck 112 is d. The ge/truck 112 has wheels which are adapted to run along the rail 120, within the guideway 124. The carriage/truck 112 is connected to a pivotable arm 114 of the frame 110,111 and is moveable along the rail 120 until it intersects with a fastener 122. The rail 120 is positioned such that the guideway 124 is substantially aligned with the span of the structure 30i.e. along the longitudinal axis A-A of the structure.

The suspended working rm -SWP 100 includes frame having a base portion 111 and two side ns 110 which are disposed on opposite sides 110', 110" of the base portion 111. At the distal end of each of the side ns 110 a ble arm 114 is provided. The frame base 111 is, in use, partially suspended h a structure 30 via the frame sides 110 and the pivotable arms 114.

The base 111 includes a counterweight system 140 which comprises a counterweight 142 which is moveable between working positions as shown and a non-working or passable position (see Figures 19and 20 for more information). The counterweight 142 moves along a pair of counterweight rails 144 using a counterweight carnage 148. The movement of the counterweight 142 is facilitated in this example using a hydraulic jack 152 powered by a motor (not shown).

Figure 12 is a perspective of an attachment system for attaching a pivotable arm 114 of the SVVP -Suspended Working Platform frame 110,1 11 to a rail 120.

The pivotable arm 114 includes an aperture 218 in which a spherical bearing 118 is housed. The carriage/truck 112 has two vertically disposed extensions 212 in between which the pivotable arm 114 is located. The extensions 212 each have an aperture (not shown) which align with each other and the aperture 218 of the pivotable arm 114 enabling a pin 214 or other fastener to secure the pivotable arm 114 to the carriage/truck 112 via the spherical bearing 118. When the carriage/truck 112 is moved along the rail, the pivotable arm 114 and thus the frame 110, 111 is moved along the rail.

Figure 13 is a perspective of a counterweight stabilizing device 140 according to the invention. A pair of counterweight rails 144 is disposed between the side portions of the frame 111 ntially parallel to the sides 110', 110" (see Figure 11) of the base of the frame 111.

The counterweight 142 is attached to counterweight e 148. The counterweight carriage 148 has wheels 248 which are adapted to run along the counterweight rail 144. A counterweight stabilizer 150 is introduced to stabilize counterweight from ng. A counterweight shield 146 covers the counterweight rail 144 and the wheels 248 of the rweight carriage 148 protecting them from damage and ingress of dirt etc...

A hydraulic jack 152 is connected to either the counterweight 142, via mounted plate 154, or to the rweight stabilizer 150 and when actuated, the jack 152 moves the counterweight 142 linearly along the path of the counterweight rails 144. Movement of the counterweight 142 is generally perpendicular to the longitudinal axis A-A of the structure 30 and this movement causes pivoting of the frame 110, 111 with respect to the structure about onal axis B-B between a free hanging and a working position when the frame 1 is stabilized to the structure 30.

Figure 14 is a perspective of a counterweight system 140 in free hanging on. The counterweight 142 is located within the internal space 310 of the frame base 11 1 i.e. the counterweight 142 is located underneath the frame base 111.

WO 20471 Figure 15 is a cross-section through a rail 120 and carriage/truck 112. The carriage/truck 112 has pairs of wheels 128 on each side of a central portion 212. The rail 120 ses an overhang 220 on each side which forms the rail guide 124 and the overhang 220 prevents the carriage/truck 120 from being removed from the rail 120. The carriage/truck 112 may be a lubricated to assist in the movement along the rail 120.

Figures 18 and 17 show different perspective views of a suspended scaffolding system 350 and Figure 18 is a transverse view of the suspended scaffolding system 350 with,standard scaffolding inflll (PERI in this case). The frame 1 is a suspended working platform and a scaffold 370 (any standard system type inflll scaffolding) is erected within the frame 110,1 11 providing a safe access and working environment for construction, inspection and maintenance work.

An upper platform 374 provides access from the structure 30 to a first ladder 378. in this example, an intermediate platform 378 is provided at the bottom of the first ladder 378 with access to a second ladder 380 which leads to the working platform 372. A skilled person will tand how many, if any, intermediate platforms are required.

The scaffold 370 is an infill, of suspended lding system and its ded working rm and can be any required system scaffolding for example PERI, but any appropriate scaffolding system can be used. The scaffold infill 370 creates a wall 382 around the perimeter of the frame base 111 and a tower 384 around the access point and ladders 0. At the corners 388 of the frame base 111 distal to the frame sides 110 i.e. the comers of the frame base 111 which are underneath the structure 30, the corner upright 392 of the scaffold wall 382 extends beyond the wall height ending in an abutment bumper or buffer 390. When the counterweight 142 is in its' working position, as shown, the abutment bumper 390 abuts the underside of the structure 30. The nt bumper is an integrated part of this invented device, not the standard scaffolding infill.

The frame sides 110 are each connected to a carriage/truck 112 which can be moved along rail 120 which is connected to a structure 30 using spaced apart distance supporting pads 128 between the rail 120 and the structure 30 and rail fasteners 122 which bridge over the rail 120.

The rail fasteners 122 are spaced apart by a nominal distance of around 200cm however this can be smaller or larger depending on the structure 30.

The rail fasteners 122 fix the rail 120 and in addition act as a stop/obstruction for the scaffolding system 350 movements, in order to move the scaffolding system 350 further along the structure, a rail fastener 122 must be temporarily doubled (one in front of, the other behind the carriage fa be moved) to allow one fastener to be removed or pivoted away from the rail 120. It is preferred that the distance and multiples of the distance between rail fasteners 122 is not the same as the distance between the two frame sides 111 so only one fastener 122 is removed or displaced at a time to allow passage of the scaffolding.

In this e, in order to move the scaffolding system 350 further along the structure, a rail support 122 must be removed or pivoted away from the rail 120. Again, it is preferred that the ce and multiples of the ce between rail fasteners 122 is not the same as the distance between the two frame sides 111 so only one fastener 122 is removed or displaced at a time to allow passage of the lding.

Figures 19 and 20 are cross sections h a suspended scaffolding system in free hanging position and g position respectively. Referring to Figure 19, the scaffolding system 350 is in its' free hanging or first on with the counterweight 142 located h the frame base 111 and the abutment bumper 390 not in contact with the underside of the structure 30. in this configuration, the scaffolding system 350 may be moved along the rail 120 enabling work, inspection or maintenance of a new n of the structure 30.

Figure 20 shows the scaffolding system 350 in a fixed or working or second position. The counterweight 142 has been displaced or moved lineally using the jack 152 towards the edge of the structure 30 and the frame sides 110 shifting the centre of gravity of the scaffolding system 350 and causing it b pivot about axis B-B (see Figure 11) via the pivoting arms 114 and forcing the abutment bumper 390 into contact with the underside of the structure 30. in other words, the counterweight 142 is moved away from the ure 30 to produce the force that pushes the suspended scaffolding s the main stable structure. This creates a stabilizing force or brace for the scaffolding system 350 ng work to be carried out safely, without the working platform experiencing dangerous uncontrollable swings or movement.

Some or all of the scaffolding system 350 may be removed from a structure when not in use as the scaffolding 370 is easy to dismantle and transport, the frame sides 110 could be unbolted from the frame base 111 and the rail 120 removed. Alternatively, the lding system 350 is left attached to a ure 30.

The lic jack may be supplemented by a hand crank in case of failure or replaced by a hand crank or alternative movement s.

In the examples shown and described herein, the rail or track 120 is shown as being located on the upper surface of the ure 30 (see Figures 1,2,7,8) however the rail may be located on the roadway surface, on a side (see Figures 5,6) or underside surface (see Figures 3,4,9,10) of the structure; the position chosen will depend in part on the design of the structure and the manner of access to the site and the ded working platform of suspended scaffolding system.

One use of the suspended working platform 100 is to provide under bridge access for carrying the construction, maintenance or inspection work to the WO 20471 lower and side surface of the structure 30. The suspended g platform 100 is delivered on the required work site in parts (dismantled or folded), then the mainframe (side frames 110 and horizontal working platform 111) and other structural parts of SWP are led together and attached to the supporting fixing points or rail 120 (by crane for example from below, or from above; by chopper; by sea ship crane). Then the whole optional add-on accessory (372,374,376,378,380,382,384,390 Figures 16, 17), machines, formwork and materials would be placed as required. The SWP allows economical assembling, disassembling and transportation. ed with the case of building up scaffolding to carry out the construction or maintenance, work efficiency is high, and cost can be erably d.

The members of the SWP are designed to be easily connected together for on-site completion, or can be pre-assembled and shipped complete to the job site.

SWP frame 100 has adjustable geometry and structure according to particular case and purposed use and is erected to the geometrical form of the structure . The dimensions and geometry of the SSS- Suspended Scaffolding System equipment varies in each particular case of use, adjusted to ic needs, the geometry of the structure to be work subject and the specific requirements of the work type to be d out, for example: ® For light maintenance jobs the working platform would be vely long, as the work progress is quick, and used ent is light(i.e. painting, cleaning.. .) ® For the work to be carried in one particular place, the working platform would be relatively short (i.e. stressing.. .) 9 For formwork job type the working platform would be deep and high to cover the work area and carry the formwork equipment It is to be appreciated that these Figures are for illustration purposes only and other configurations are possible The invention has been described by way of several embodiments, with modifications and alternatives, but having read and tood this description further embodiments and modifications will be apparent to those skilled in the art. All such embodiments and cations are intended to fall within the scope of the present invention as defined in the accompanying claims.

Claims (4)

Claims

1. A suspended scaffolding system or form-work system that includes a connector system adapted to engage a fixture/ the connector system includes connectors that permit relative movement with respect to the e in two orthogonal planes, the fixture in use is in contact with a surface of a main stable structure/ an arm connects a suspended object of the suspended lding system to the connector system, so that in use the ded lding system is suspended below the main stable structure, characterised in that at last one moveable counterweight is provided on the suspended scaffolding system/ which is adapted to be displaced from a first position to a second position so as to change the position of center of gravity of the suspended scaffolding system, allowing suspended scaffolding system to be ized against the main stable structure with counterweight in second position or hang freely or easy move freely along e with counterweight in first position.

2. A suspended scaffolding system or form-work system according to claim 1, wherein a method of mechanical or manual displacement of mass is provided to displace the counterweight for indicating the force pushing the suspended scaffolding system to be safely stabilized against the main stable structure.

3. A suspended scaffolding system or form-work system according to any preceding claim/ that is stabilized against the main stable structure by adjusting the location of the center of gravity of the suspended lding system away from a neutral position thereby ing a stabilizing force by moving at least one counterweight connected with the suspended scaffolding system.

4. A method of stabilizing the suspended scaffolding system according to any preceding claim n/ the adjustment of the location of the center of gravity is achieved by one or more of counterweight's movements: swing, translation/transposition, or by changing the distribution of weight in rweight area by transferring any liquid or loose material from one ballast tank to another tank/ or by moving 206437NZ_claims_20150624_PLH ^4 pieces of counterweight from one location to r location on the suspended scaffolding system.