GB2640910A

GB2640910A - Height extender and ancillary components for a work platform

Info

Publication number: GB2640910A
Application number: GB2406498.2A
Authority: GB
Inventors: Clear Liam
Original assignee: Safestand Ltd
Current assignee: Safestand Ltd
Priority date: 2024-05-09
Filing date: 2024-05-09
Publication date: 2025-11-12
Also published as: WO2025233178A1; GB202406498D0

Abstract

A work platform or trestle assembly is disclosed. The modular system allows additional height to be added to the work platform (or bandstand) without the need for specialist workers. It is formed from a modular system of stands 10, each having a frame comprising a pair of upright supports 16, 18 connected by a first crossmember 20 for supporting a first work platform 12. One of the upright supports has an integral upward extension 16a, above the first crossmember for attaching horizontal rails to form a safety barrier. A removable post 30 is provided at the opposite end of the first crossmember 20 for attaching horizontal rails to form a further removable safety barrier. The work platform assembly also has a number of height extension arrangements, each with a first leg to replace the removable post and a second horizontal crossmember for supporting a second work platform. At its end, adjacent to the first leg, the second cross member has either: (a) a fixed post, or (b) a fitting for receiving one of the removable posts. There is also a second upward leg, positioned at the end of the second crossmember opposite to the first leg, for attaching further horizontal rails.

Description

HEIGHT EXTENDER AND ANCILLARY COMPONENTS FOR A WORK PLATFORM

[0001] This invention concerns a modular system of stands and associated components which are assembled to provide a work platform or platforms which can be used for example to construct masonry walls. Known trestle systems used to support a work platform at a low elevated height compared to the heights achievable using scaffolding are shown for example in EP 1660738 B1 and W02005/124057 Al. The trestles (sometimes called "bandstands") act as stands on which the work platform rests and comprise frames which, at least for the purposes of initial assembly of the system, maintain themselves in an upright position. Unlike scaffolding, such trestle systems can be safely set up by non-specialist personnel with little training or supervision, e.g. by following the instructions provided in a training manual. For safety, both scaffolding and these known trestle systems are provided with edge protection, to prevent workers and work materials etc. from accidentally falling from the work platform.

[0002] Work platform heights of up to about 2.2 metres are achievable using these known trestle systems. Workers standing on the platform can therefore safely and comfortably build masonry walls up to about 4 metres in height. Two-storey buildings may typically require walls to be built to a height of around 5 -5.5 metres.

Building the final "lift" of masonry in that case may require complete removal of the trestle system, to allow its replacement by scaffolding. The additional work and the need to bring in a specialist trade to set up the scaffolding may negate some of the benefits of using the trestle system in the first place.

[0003] The present invention provides a work platform assembly comprising a modular system of stands, in which each stand comprises a frame comprising a pair of upright supports connected by a first crossmember upon which a first work platform is supported in use, one of the upright supports having an integral upward extension above the first crossmember reaching to a height at which one or more generally horizontal rails can be attached to form a safety barrier, the first crossmember being provided at its end opposite the integral upward extension with a removable post, with a first fitting for receiving a lower end of the removable post, and with one or more further generally horizontal rails which can be attached to the removable post to form a further safety barrier; the removable post and further generally horizontal rails being selectively removable in use, and the work platform assembly further comprising a plurality of height extension arrangements, each comprising: a first leg receivable in one of the first fittings to extend generally vertically therefrom; a second crossmember extending generally horizontally from the upper end of the first leg for supporting a second work platform; the second crossmember at its end adjacent to the first leg having either: (a) a fixed post, or (b) a second fitting for receiving one of the removable posts or a further such removable post; the second crossmember having at its end opposite to the first leg a second leg extending upwardly in use for attachment of one or more generally horizontal rails to form a safety barrier.

[0004] Therefore, when a wall under construction reaches or exceeds the height of the further safety barrier, the removable posts can be removed, as the wall will then provide the necessary edge protection at the working side of the first work platform. Each removable post can be replaced by or used to comprise a part of a respective one of the height extension arrangements. The further generally horizontal rails can be fitted to the first legs, other generally horizontal rails fitted to the second legs, the removable posts or the further removable posts inserted in the second fittings (if used), and further generally horizontal rails fitted to the posts and second legs to provide safety barriers at either end of the second crossmembers. The second work platform can then be supported on the second crossmembers, above the first work platform. Both longitudinal edges of the second work platform are thereby protected by safety barriers in substantially the same way as the corresponding longitudinal edges of the first work platform, below. The removable posts or further removable posts and safety rails at the working side of the second work platform may be selectively removed as the masonry of a wall under construction reaches a height sufficient to provide the necessary edge protection, and/or to provide localised access to the work area during masonry laying; in the same way that these posts and rails are selectively removable at the working side of the first work platform as work progresses.

[0005] The second crossmember may have at its end opposite to the first leg a third fitting connectable to the upper end of the integral upward extension for supporting the second crossmember thereon. The second crossmember in that case may be of substantially the same length as the first crossmember, whereby the second work platform may be substantially as wide as the first work platform.

[0006] Alternatively, the second crossmember may have at its end opposite to the first leg a third leg for supporting the second crossmember on the first work platform. The second crossmember may in that case be of a shorter length than the first crossmember, whereby the second work platform is narrower than the first work platform. This may provide a space beside the second work platform, e.g. allowing for ladder access between the first and second work platforms. The third leg may be permanently fixed to the second crossmember, to provide a substantially rigid and very stable connection. Alternatively, the third leg may be detachably connected to the second crossmember, e.g. for ease of transport and storage of the height extension arrangement.

[0007] The second leg may be permanently fixed to the second crossmember, to provide a robust safety barrier and very stable connection at the non-working side of the second work platform. Alternatively, the second leg may be removably attached to the second crossmember, e.g. for ease of transport and storage of the height extension arrangement. The removably attached second leg may be, or may be interchangeable with, one of the removable posts, [0008] The first leg may be permanently fixed to the second crossmember, to replace the corresponding removable post. Alternatively, at least a portion of the first leg may be removably attached to the second crossmember, e.g. for ease of transport and storage of the height extension arrangement. The removably attached portion of the first leg may be, or may be interchangeable with, one of the removable posts, and/or with the removable second leg, if used.

[0009] Both the first and the second leg may be permanently fixed to the second crossmember to provide a rigid height extension frame. In that case, it has been found that that the second work platform can be made adequately stable for final use without the need for any cross-bracing or framing in the height extension arrangements (either longitudinally or transversely of the work platform assembly). The generally horizontal rails fitted between the permanently fixed second legs and between the permanently fixed first legs each also help to further stabilise the height extension arrangements.

[0010] The integral upward extension, removable post, removably attached portion of the first leg and the second leg may be of substantially equal length, with the third fitting (when used) depending substantially directly from the second crossmember of the height extension arrangement. The second work platform is thereby supported above the first work platform by substantially the height of integral upward extension and the height of the removable post, i.e. the second work platform is supported above the first work platform by substantially the heights of the safety barriers on either side of the first work platform -typically a little over 1 metre higher.

[0011] The first leg of the height extension arrangement may be longer than the removable post, and the third fitting or third leg (as applicable) may be correspondingly elongated. For example, the third fitting may comprise an extension piece aligned with the second leg and extending below the second crossmember. In this way, the second work platform may be supported above the first work platform at a height which is greater than that of the removable post and integral upward extension.

[0012] A plate-like kickboard retaining bracket may extend upwardly from the second crossmember of the height extension arrangement, inboard of the second leg.

[0013] An overhanging end of the second work platform may be supported by an anti-flip bracket fitted to the second crossmember of the height extension arrangement adjacent to those ends.

[0014] An end of the second work platform may be supported above the first work platform and an access staircase fitted between the first platform and the second platform.

[0015] The access staircase may be supported by an anti-flip bracket at the end of the second work platform supported above the first work platform.

[0016] The access staircase may be fitted with a safety gate at the corresponding end of the second work platform.

[0017] The invention and some of its further features and advantages is further described below with reference to illustrative embodiments shown in the drawings, in which: FIG. 1 diagrammatically shows a stand supporting a first work platform, prior to fitment of any a height extension arrangements; FIG. 2 shows the stand of FIG. 1 fitted with a height extension arrangement to form a modular system embodying the present invention; FIG. 3 shows a rigid frame used to comprise the height extension arrangement of FIG. 2; FIG. 4 shows a second embodiment of the invention using the stand of FIG. 1, fitted with another example of a height extension arrangement; FIG. 5 shows a rigid height extension frame as used in the height extension arrangement of FIG. 4; FIG. 6 shows three height extension frames similar to that of FIG. 3 installed ready for completion of safety barriers and boarding-out to form the second work platform; FIG. 7 corresponds to FIG. 6 but shows the second work platform and its safety barriers fully installed above the first work platform, viewed from the non-working side; FIG. 8 corresponds to FIGs. 6 and 7 but shows the completed work platforms viewed 20 from one end and from the working side; FIGs. 9 and 10 are views from above and below respectively of an anti-flip bracket adapted to support an access staircase; FIG. 11 shows the anti-flip bracket of FIGs. 9 and 10 from below, installed and supporting an access staircase; FIG. 12 shows the anti-flip bracket of FIG. 11 from above, with some of the second platform boards displaced to show engagement of a staircase support hook; FIG. 13 diagrammatically shows a third embodiment of the present invention; FIG. 14 diagrammatically shows a fourth embodiment of the present invention; FIG. 15 diagrammatically shows a fifth embodiment of the present invention; FIGs. 16-19 diagrammatically show still further embodiments of the present invention; FIG. 20 shows a safety barrier extension bracket which may be used as an ancillary component in the modular work platforms with which this invention is concerned; FIG. 21 shows a further such ancillary component for accommodating toeboards at the working sides of the work platforms, and FIG. 22 is a diagrammatic top plan view of a special form of guardrail which may be used when setting-up modular work platforms embodying the present invention.

[0018] FIG. 1 shows an example of a stand 10 supporting a first work platform 12, which may be used as a starting point in assembling some embodiments of the invention. The stand 10 comprises a frame 14 formed by a pair of upright supports 16, 18 connected by a first crossmember 20. The first work platform 12 may be made up of scaffolding boards 22 supported on the first crossmember 20. The scaffolding boards 22 are shown in transverse cross-section in FIG. 1. Other such stands (not shown in FIG. 1) are placed in a line in front of and/or behind the stand 10, with the scaffolding boards 22 spanning longitudinally between adjacent crossmembers 20. The upright supports 16, 18 may be telescopically received in and maintained upright by a base framework 24. Thus, the height of the stand 10 may be adjusted by selectively engaging captive locking pins 26 in one of a series of holes (not shown) spaced along the lengths of the upright supports 16, 18.

[0019] The upright support 16 has an integral upward extension 16a above the first crossmember 20, reaching to a height suitable for forming a safety barrier at a non-working side of the first platform 12. Opposite sides of the upward extension 16a facing longitudinally of the first platform 12 are provided with paired receptors 28, for example one pair being close to the top of the upward extension 16a and another pair being for example positioned slightly above the mid-height of the upward extension 16a (only one receptor of each pair being visible in FIG. 1). The receptors 28 are configured to receive end parts of safety rails (not shown) whereby the safety rails may be securely attached in series to span generally horizontally between the upward extensions of adjacent stands 10 and form the safety barrier. For example, the receptors may be pockets adapted to receive attachment pegs or pins projecting laterally downward from the ends of safety rails. Other suitable rail attachment arrangements may be used. For example, the receptors may comprise upwardly projecting pins or pegs and the ends of the safety rails may comprise downwardly open sockets configured to receive the upwardly projecting receptor pins or pegs. The safety rails may be telescopic, e.g. to allow the spacing between adjacent stands 10 to be varied.

[0020] The first crossmember 20 is provided at its end opposite the integral upward extension 16a with a removable post 30 and with a first fitting 32 for receiving a lower end of the removable post 30. For example, as shown in FIG. 1, the first fitting 32 may comprise a socket largely depending from the end of the first crossmember 20 outboard of the upright support 18;. Alternatively, the upper end of the upright support 18 may provide a socket or fitting for receiving the lower end of the removable post 30. The removable post 30 is provided on opposite sides with paired receptors 28 configured similarly to the receptors on the upward extension 16a, whereby further safety rails may be securely attached in series to span generally horizontally between the removable posts 30 of adjacent stands 10. For simplicity and modular flexibility, the safety rails and further safety rails may be of the same kind/interchangeable. The receptors 28 may be provided on the integral upward extension 16a and removable post 30 at corresponding heights above the first platform 12 when the removable post 30 is installed. Other safety rails can then be installed generally horizontally between the upward extension 16a and removable post 30 at one or both ends of the first platform, to continue and complete the safety barrier there. Telescopic safety rails can be used both longitudinally and transversely of the first platform 12. Similarly, telescopic safety rails may easily be temporarily fitted to extend transversely or diagonally across the first platform 12 to form a (progressively reconfigured) protected safety cell. A worker can fit or remove the full set of removable posts 30 and safety rails required for proper edge protection of the first platform 12 from within this cell, during set-up or dismantling of the work platform assembly. One end of, or the non-working side of, the first platform 12 may be fitted with a safety gate for access purposes, for example as described in UK patent application no. 2314273.0 and W02008/110812 Al. The first crossmember 20 may be provided with an upstanding plate-like bracket 34 just inboard of the upward extension 16a, for retaining a longitudinally extending toeboard 36 between the bracket 34 and the upward extension 16a.

[0021] The removable posts 30 and further generally horizontal rails are selectively removable so that for example as building of a masonry wall progresses, these rails may be selectively removed to access the work area. When the wall is sufficiently high (e.g. about 1 m) above the working side of the first platform 12 to provide the required edge protection there, the removable posts 30 and the associated further safety rails can be removed.

[0022] To allow work to progress even higher (e.g. when constructing a two-storey building), at least some of the stands 10 of the work platform assembly can be fitted with respective height extension arrangements. Like the stands 10, the height extension arrangements can be formed for the most part from welded mild steel box (e.g. square) tubing, for adequate strength and ruggedness. As illustrated in FIGs. 2 and 3, each height extension arrangement 50 comprises a first leg 38 receivable in the first fitting 32 to extend generally vertically from the corresponding stand 10. For example, a bottom end of the first leg may comprise a spigot 48 receivable in the first fitting (socket) 32. The first leg 38 may be provided with safety rail attachment receptors (for example pockets 28) configured similarly to those on the removable post 30 of the stand 10. Thus, further safety rails may be attached between the first legs 38 of adjacent height extension arrangements 50 in the same way as they are attached between the (now replaced by the first legs 38) removable posts 30 of adjacent stands 10 at the working side of the work platform assembly. The first leg 38 may be provided with an additional safety rail attachment receptor (e.g. pocket) 28a to provide for fitment of a third set of generally horizontal safety rails in a bottom region at the working side of the first work platform 12.

[0023] The height extension arrangement 50 additionally comprises a second crossmember 40 extending generally horizontally from the upper end of the first leg 38 for supporting a second work platform 42 above the first work platform 12. The first leg 38 may be rigidly and permanently attached to the second crossmember 40, e.g. by welding. Like the first work platform 12, the second work platform 42 may be made up of scaffolding boards 22 supported on the second crossmember 40 and spanning longitudinally to second crossmembers 40 of other adjacent height extension arrangements 50. The second work platform 42 can thus be adequately supported along its entire length. When it is anticipated that height extension arrangements 50 are to be used, an endmost stand 10 can be fitted with a height extension arrangement from the outset, so that the edge protection at that end of the first work platform is not disrupted when fitment of the remainder of the height extension arrangements is initiated. The second crossmember 40 may be provided with a toeboard retaining bracket 34 which co-operates with the second leg 46 to retain a toeboard 36 at the non-working side of the second work platform, in the same way that the bracket 34 on the first crossmember 20 co-operates with the upward extension 16a to retain the toeboard at the non-working side of the first work platform 20.

[0024] The second crossmember 40 at its end adjacent to the first leg 38 may have a second fitting 44 (for example a socket) for receiving one of the removable posts 30 now replaced by the first legs 38. Or the second fitting 44 may receive a further removable post 30a. For simplicity and modular flexibility, the removable post and further removable post 30a may be of the same kind/interchangeable. Yet alternatively, the post 30a may be permanently attached (e.g. welded) to the second crossmember 40.

[0025] The second crossmember 40 has at its end opposite to the first leg 38 a second leg 46 extending upwardly in use for attachment of one or more generally horizontal safety rails, to form a safety barrier. For example, the second leg 46 may be provided with safety rail attachment receptors 28 configured similarly to those on the integral upward extension 16a of the stand 10. Thus, other safety rails may be attached between the second legs 46 of adjacent height extension arrangements 50 in the same way as they are attached between the upward extensions 16a of adjacent stands 10 at the non-working side of the work platform assembly. The second leg 46 may be rigidly and permanently attached to the second crossmember 40, e.g. by welding. Where both the first and second legs 38, 46 are permanently attached to the second crossmember 40 in this way, the height extension arrangement 50 may comprise a rigid, generally crank-handle shaped unitary frame, as shown in FIG. 3, with good inherent stability advantages as previously discussed.

[0026] The second crossmember 40 may have at its end opposite to the first leg 38 a third fitting 52 connectable to the upper end of the integral upward extension 16a for supporting the second crossmember 40 at that end (i.e. at the non-working side of the work platform assembly). For example, the third fitting 52 may comprise a spigot snugly receivable in the hollow upper end of the integral upward extension 16a of the stand 10 as a close sliding fit.

[0027] The integral upward extension 16a, removable post 28, first leg 38 and second leg 46 may be of substantially equal length, with the third fitting 52 (when used) depending substantially directly from the second crossmember 40 of the height extension arrangement 50. Thus, the second work platform 42 is supported above the first work platform 12 by a distance substantially equal to the heights of the original safety barriers on either side of the first work platform 12.

[0028] In an alternative (second) embodiment shown in FIGs. 4 and 5, the first leg 38 of the height extension arrangement 50 may be longer than the removable post 30, and the third fitting may be correspondingly elongated, so that the second crossmember 40 and second platform 42 are again supported substantially horizontally above the first platform 12. For example, the third fitting 52 may comprise a spigot 52a receivable in the hollow upper end of the integral upward extension 16a as a close sliding fit and which depends from a tubular extension piece 16b aligned with the second leg 46 and extending below the second crossmember 40.

The second work platform 42 can thereby be supported for example about 1.8 m above the first work platform 12 (or higher, e.g. within the maximum height of a wall buildable by workers standing on the first platform 12, prior to installation of the height extension arrangements 50). Workers can thereby continue to use the first work platform 12 without stooping, after installation of the height extension arrangements 50 and the second platform 42.

[0029] FIG. 6 shows three height extension arrangements 50 and corresponding removable posts 30a installed above a portion of the first work platform 12, ready for boarding-out to form a second work platform (not yet installed). Some of the safety rails 54 which will provide edge protection for the second work platform are shown already fitted to the second legs 46 and removable posts 30a. In the case of height extension arrangements as in FIGs. 2 and 3 which support the second work platform at the level of the top of the safety barrier for the first work platform 12, this can be safely carried out by a worker standing on the first work platform 12, because the uppermost attachment pockets 28 on the removable posts 30a and second legs 46 will typically be less than about 2.1 m above (and therefore reachable from) the first work platform 12.

In the case of higher height extension arrangements e.g. as shown in FIGs. 4 and 5, the removable posts 30a may again be safely fitted from the first work platform 12 prior to boarding-out the second work platform 42. But at least the uppermost safety rails 54 for the second work platform 42 may have to be fitted by a worker standing on the second work platform 42 and working from within a temporary safety cell formed by other telescopic safety rails 54, in the same way that the safety rails for the first work platform 12 are typically installed.

[0030] Before the height extension arrangements 50 are installed, the wall at the working side of the first work platform 12 is built to a height sufficient to protect that side, allowing safe removal of the removable posts 30 and their corresponding safety rails. These may then be replaced by the height extension arrangements 50, with their first legs 38 held in the first fittings 32. Safety rails may be fitted to the first legs 38 despite the presence of a protective wall at the working side of the first work platform 12, to further enhance the stability of the height extension arrangements 50 and second work platform 42. For example, fixed length, non-telescopic rails may be fitted, due to their greater rigidity. However, an endmost post 30 cannot be safely removed, as this would disrupt the edge protection at the end of the first platform 12 (the right-hand end as shown in FIG. 6). To circumvent this problem, when a second platform 42 is to be used, a height extension arrangement 50, rather than a removable post 30, may be fitted at the end of the first platform 12 from the outset. Additionally or alternatively, a special form of guardrail may be used when setting up the height extension arrangements 50, as further explained below with reference to FIG. 22.

[0031] FIGs. 7 and 8 show a completed second work platform 42 supported above the first work platform 12 on three height extension arrangements 50, configured as shown in FIG. 6. However, the modular system of stands, height extension arrangements and other ancillary components described herein is highly adaptable to suit many different configurations of work site. For example, the platforms concerned can be made to substantially any required length, and may include bends/corners. At least one end of the second work platform 42 may be accessed e.g. from the level of the first platform 12 or from ground or floor level, by an access staircase 56 e.g. as described in UK patent application no. 2314273.0.

Alternatively, as described in that application, the non-working side of the second work platform 42 may be accessed from ground or floor level, by at least one such an access staircase. The top end of any access staircase may be provided with a safety gate (58, FIG. 7) e.g. as also described in UK patent application no. 2314273.0. The first work platform 12 may similarly be provided with at least one access staircase and safety gate at its non-working side or at at least one end. Any overhanging ends of the boards 22 forming the first work platform 12 or the second work platform 42 may be supported by anti-flip brackets 60 in the usual way. (See e.g. GB 2378978 A).

Transverse toeboards 62 may be provided at work platform ends as required, e.g. hung off the longitudinal toeboards 36 by brackets 64 as described e.g. in GB 2420822 A. [0032] FIGs. 9 and 10 show a special, more robust, anti-flip bracket 60a, which may be used to support the access staircase 56 at an end of the first work platform 12 or at an end of the second work platform 42. Like the anti-flip bracket disclosed in GB 2378978 A, the anti-flip bracket 60a may be fabricated from mild steel and comprises a pair of downwardly open channel members 66 linked end to end by a flat strip 68. The channel members 66 are sized to fit over the first crossmember 20 (of an endmost stand 10) or, as the case may be, the second crossmember 40 (of an endmost height extension arrangement 50) as a tight sliding fit, whereby the strip 68 lies along the top face of that crossmember. The anti-flip bracket 60a further comprises a supporting frame 70 positionable under the overhanging board ends in use. The supporting frame 70 is made for example from heavier gauge box section than the usual anti-flip bracket as shown in GB 2378978 A, whereby its distal edge part 72 has substantially the same external cross-section as the first or second crossmember 20, 40. Instead of having a simple D-shape, the supporting frame 70 may additionally comprise a further pair of box-section inner struts 74 fixed (e.g. welded at either end) between the channel members 66 and the distal edge part 72. Additional central support struts 76 may be provided as indicated in broken lines in FIG. 9, e.g. to provide support for smaller board overhangs. A single continuous channel member may be used in place of the two channel members 66 and strip 68.

[0033] FIGs. 11 and 12 show one of the special anti-flip brackets 60a fitted to the second crossmember 40 of an endmost one of the height extension arrangements for supporting the upper end of an access staircase 56, as well as for supporting overhanging ends of boards 22 making up the second work platform 42. FIGs. 11 and 12 show the access staircase 56 extending between the first work platform 12 and the second work platform 42 as in FIGs. 7 and 8. A pair of support hooks 78 at the upper end of the access staircase 56 are hooked over the distal edge part 72 of the anti-flip bracket 60a to suspend the upper end of the staircase 56 therefrom.

[0034] FIG. 13 diagrammatically illustrates a third embodiment of the invention in which the first leg 38 of the height extension arrangement 50 is removably attached to the second crossmember 40, e.g. for ease of transport and storage of the height extension arrangement. The removably attached first leg 38 may be, or may be interchangeable with, one of the removable posts 30, 30a at the working side of the first or second work platform 12, 42. The first leg 38 may be removably received by a fourth fitting 52b fixed to the second crossmember 40 of the height extension 0 arrangement 50. For example, the fourth fitting 52b may comprise a spigot received as a close sliding fit within a hollow top end of the first leg 38 and for example extending oppositely to the second fitting or socket 44 at the same end of the second crossmember as the second fitting 44. In this embodiment, the second leg 46 is permanently fixed to the second crossmember 40, e.g. by welding.

[0035] FIG. 14 diagrammatically illustrates a fourth embodiment of the invention in which both the first leg 38 and the second leg 46 of the height extension arrangement 50 are removably attached to the second crossmember 40. The removably attached second leg 46 may be substantially the same as, or interchangeable with, the first removable leg 38 and/or with one of the removable posts 30, 30a. The second leg 46 may be removably received by a fifth fitting 44a fixed to the second crossmember 40 of the height extension arrangement 50. For example, the fifth fitting 44a may comprise a socket for receiving a lower end of the second leg 46 as a close sliding fit.

[0036] FIG. 15 diagrammatically illustrates a fifth embodiment of the invention which generally corresponds to the embodiment shown in FIG. 14, in that the second leg 46 and a portion 38a of the first leg of the height extension arrangement 50 are removably attached to the second crossmember 40, substantially as shown in FIG. 14. However, this fifth embodiment also resembles the embodiment shown in FIGs. 4 and 5, in that the third fitting 52 is elongated. For example, the third fitting 52 may comprise a spigot 52a receivable in the hollow upper end of the integral upward extension 16a and which depends from a tubular extension piece 16b which itself depends below the second crossmember 40. The fourth fitting 52b is correspondingly elongated, for example comprising a depending tubular extension piece 38b which forms an upper part of the first leg which remains fixed to the second crossmember 40. A spigot 52c at the lower end of the fourth fitting 52b is insertable in the hollow top end of the removable portion 38a of the first leg or removable post 30, 30a comprising the removable portion 38a of the first leg, as a close sliding fit. The extension pieces 16b, 38b may be of substantially equal length, whereby the second crossmember is supported substantially horizontally above the first work platform 12, at a height greater than the safety barriers for the first work platform 12 supported by the integral upward extension 16a and the removable post 30. The extension piece 38b therefore comprises a non-removable portion of the first leg complementary to the removable portion 38a of the first leg. In a variant of this embodiment, the second leg 46 may be permanently attached to the second crossmember 40, similarly to the height extension arrangements shown in FIGs. 5 and 13.

[0037] FIGs. 16-19 diagrammatically illustrate still further embodiments of the invention, in which the second crossmember 40 of the height extension arrangement 50, rather than comprising a third fitting 52 connectable to the upper end of the integral upward extension 16a of the stand 10, instead comprises at its end opposite to the first leg 38 a third leg 152 for supporting the second crossmember 40 on the first work platform 12. The second crossmember 40 may therefore be made shorter than the first crossmember 20 whereby the second work platform 42 is narrower than the first work platform 12. In such embodiments the third leg 152 may be made to a suitable length to support the crossmember 40 substantially horizontally when the first leg 38 is received in the first fitting 32. The first leg 38 may be the same length (height) as the removable post 30 or longer, with the length of the third leg 152 configured to match. The first leg 38 may be provided with safety rail attachment receptors (not shown) in corresponding positions relative to its lower end as are the safety rail attachment receptors on the removable posts 30, 30a. A continuous safety barrier may thereby be maintained around all edges of the first work platform 12 after fitment of the height extension arrangements 50.

[0038] In the height extension arrangement 50 shown in FIG. 16, the first, second, and third legs 38, 46, 152 are all permanently attached (e.g. welded) to the second crossmember 40 to form a rigid frame. In FIG. 17, only the first leg 38 is detachable from the second crossmember 40; the other two legs being substantially the same as those shown in FIG.16. In FIG. 18, the first and second legs 38, 46 are each detachable from the second crossmember 40 and the third leg permanently attached (e.g. welded) to the second crossmember 40. In FIG. 19, the first, second, and third legs 38, 46, 152 are all detachable from the second crossmember 40.

[0039] In variants of FIGs. 17-19 in which the first and third legs 38, 152 are longer than the second leg 46 whereby the second work platform 42 is supported at a height greater than that of the original safety barriers of the first work platform 12, the first leg may comprise a detachable portion of substantially equal length to the removable posts 30, 30a (and to the second leg 46), whereby the detachable portion of the first leg 38 is substantially the same as, or interchangeable with, the removable posts 30, 30a. In such variants, the first leg may comprise a complementary portion which remains attached to the second crossmember 42, e.g. as shown in and described above with reference to FIG. 15, mutatis mutandis. The removable attachment of the second leg in FIGs. 18 and 19 may be as shown in and described above with reference to FIGs. 14 and 15, mutatis mutandis. The post 30, 30a may be permanently attached to the second crossmember 42.

[0040] The narrower second work platform 42 provides for a space or passageway 80 along the first work platform 12, between (a) the safety barrier at the non-working side of the first work platform 12 and (b) the third legs 152 and non-working side of the second work platform 42. As shown in FIGs. 16 and 17 (but also as applicable to FIGs. 18 and 19) a ladder 82 for accessing the second work platform 42 from the first work platform 12 may be positioned in the space or passageway 80, e.g. secured to a ladder support bracket 84 fitted to the top of the second leg 46 of one of the height extension arrangements 50. The ladder support bracket 84 may accommodate (act as a keeper for) a safety gate fitted to the second leg 46 of an adjacent height extension arrangement 50, whereby the safety gate provides protected access between the ladder 82 and the second work platform 42 through the safety barrier at the non-working side of the second work platform 42. The ladder support bracket 84 and safety gate may be configured as described in W02008/110812 Al.

[0041] Ladder access between the first work platform 12 and a second work platform 42 of the same width (e.g. in addition to or as an alternative to the access staircase described above with reference to FIGs. 7-12) may be provided by means of a ladder support bracket and safety gate hung from the second leg 46 and removable post 30, 30a associated with e.g. a height extension arrangement 50 next to an endmost height extension arrangement 50. The ladder support bracket may be as described in UK patent application nos. 2317813.0 and 2405283.9. The safety gate is therefore releasably held closed across the second work platform above the second crossmember of this penultimate height extension arrangement. The boards of the second work platform 42 may terminate at this second crossmember, to leave an opening in the second work platform 42 through which the ladder extends next to the safety gate. Workers can thus step sideways between the ladder and the end of the second work platform through the opened safety gate. The safety rails of the second work platform 42 may be fitted to all the height extension arrangements 50 and their corresponding removable posts 30, 30a (including the endmost height extension arrangement 50 and its removable post 30), whereby the resulting safety barrier also surrounds and protects the platform opening and the upper end of the ladder.

[0042] FIGs. 16 -19 also show an extension piece 86 inserted into the hollow upper end of the integral upward extension 16a of the stand 10 to support a third set of generally horizontal safety rails (not shown) and so extend the height of the safety barrier at the non-working side of the first work platform 12. The extension piece 86 may be as described in GB 2605607 A. The height of any of the other safety barriers described herein (i.e. including any at the working side and ends of the first work platform and any at any side or end of the second work platform) may be similarly extended. Such extension pieces may also be fitted to the safety barriers on both sides of the first work platform, to further increase the height of the second work platform above the first work platform in modifications of the embodiments shown in FIGs. 14 and 15. In any of the fittings described herein comprising a spigot attached to a first part and receivable in a socket attached to a second part, where technically feasible, the relative positions of the spigot and socket may be reversed, so that the spigot is instead attached to the second part and the socket is instead attached to the first part.

[0043] Further height extension arrangements 50 may be added to those of the second work platform 42, to provide a third (or higher) work platform. Where necessary or desired, the stability of any of the work platform assemblies described herein may be enhanced e.g. by tying them in to the masonry at their working side, by buttress legs or poles extending at right angles diagonally downward from the nonworking side to the ground or floor, and/or by additional longitudinal and/or transverse cross-bracing or framing. For example, diagonal cross-braces as described in GB2421538 may be fitted between adjacent ones of: integral upward extensions 16a, first legs 38, second legs 46, and/or third legs 152, to the extent necessary to provide the required stability. Additionally or alternatively, fixed length, non-telescopic safety rails may be fitted between adjacent stands 10 and their height extension arrangements 50, e.g. where those stands 10 are cross-braced to one another and therefore constrained to be at a substantially fixed spacing in any case.

(See for example the safety rail positions 54a indicated in FIG. 7).

[0044] FIG. 20 shows a safety barrier extension bracket 88 having attachment pins 90 receivable in the receptor pockets 28 on an endmost post 30, 30a (or on the like: such as on an upright extension 16a, or on the first, second or third leg 38, 46, 152). The bracket 88 is thus attachable to be cantilevered out from that post etc., to form a continuation of the safety barrier comprised by that post etc. The bracket 88 has a pair of receptors (e.g. pockets) 28a at its outboard end for reception of safety rails 54 (only a lower such rail shown fitted). These safety rails are therefore supported cantilevered out from the post 16a or the like, for example above the overhanging boards at one end or at a corner of a work platform. Additionally or alternatively, receptors (one such receptor pocket 28a' being indicated in broken lines in FIG. 20) may be provided at the outboard end of the bracket on either or both lateral sides thereof. Anti-rotation plates 92 or the like (one such plate being indicated in broken lines in FIG. 20) may extend outward from the bracket 88 to embrace (e.g. opposite) sides of the post 30, 30a or the like, to prevent the bracket 88 from rotating about the attachment pins 90.

[0045] FIG. 21 shows a bracket 94 for securing toeboards at the working side of the first or second platform 12, 42. The bracket 94 comprises a tubular sleeve 96 which is slipped over the lower end of a removable post 30, 30a, before that end is inserted into its supporting socket 32, 44. An upwardly open, U-shaped channel member 98 is fixed (e.g. welded) to the sleeve 96, for reception of the toeboard (not shown). The toeboard may thus be removably secured along the edge of the platform 12, 42 at the working side by a series of such brackets 94. Some or all the brackets may be inverted compared to the position shown, so that they drop down over the top edge of the toeboard, rather than receiving the toeoard from above.

[0 04 6] FIG. 22 shows in schematic plan view a special form of temporary "advance guardrail" 102 which may be used for safety when setting out the height extension arrangements 50 on the stands 10. The advance guardrail 102 comprises a respective depending spigot 104 at either end, respectively for reception in the open top end of the tubular post 30 at the working side of the first platform 12, and in the open top end of the tubular integral upward extension 16a at the non-working side of the first platform 12. The spigots 104 may be of square cross-section rather than the schematically indicated round cross-section. For example, the spigots 104 and the remainder of the advanced guardrail may all be fabricated from the same size of steel box section tubing. A central part 106 of the advanced guardrail 102 is outwardly bowed to one side of end parts 108. When the spigots 104 are inserted in tops of the penultimate post 30 and penultimate upward extension 16a adjacent to one end of the first platform 12, the bowed central part 106 can be orientated (generally horizontally) towards the platform end. This allows an operative to stand closer to the corner post at the platform end. The operative can thereby more easily reach and remove the corner post and associated safety rails, working from within the safe confines of the advance guardrail 102 and the previously installed safety barriers around the remainder of the edges of the first platform 12. The non-bowed end parts 108 of the advanced safety rail 102 keep the operative a safe distance from the platform edges during this process. The endmost height extension arrangement 50 can then be safely fitted from within the bowed central part 106; the endmost first fitting (socket) 32 and upper end of the endmost upward extension 16a again being within easy reach of the operative. All required safety rails can then be fitted to the endmost height extension arrangement SO, again working from within the safe zone of the advanced safety rail 102. Where necessary, using the advanced guardrail 102 in a similar way, further removable posts 30 and their associated safety rails can be successively removed and replaced by further height extension arrangements SO and safety rails (re)attached. For example, this may be required if there is no suitable wall to provide edge protection at the working side of the first platform 12.

Claims

CLAIMS1. A work platform assembly comprising a modular system of stands, in which each stand comprises a frame comprising a pair of upright supports connected by a first crossmember upon which a first work platform is supported in use, one of the upright supports having an integral upward extension above the first crossmember reaching to a height at which one or more generally horizontal rails can be attached to form a safety barrier, the first crossmember being provided at its end opposite the integral upward extension with a removable post, with a first fitting for receiving a lower end of the removable post, and with one or more further generally horizontal rails which can be attached to the removable post to form a further safety barrier; the removable post and further generally horizontal rails being selectively removable in use, and the work platform assembly further comprising a plurality of height extension arrangements, each comprising: a first leg receivable in one of the first fittings to extend generally vertically therefrom; a second crossmember extending generally horizontally from the upper end of the first leg for supporting a second work platform; the second crossmember at its end adjacent to the first leg having either: (a) a fixed post, or (b) a second fitting for receiving one of the removable posts or a further such removable post; the second crossmember having at its end opposite to the first leg a second leg extending upwardly in use for attachment of one or more generally horizontal rails to form a safety barrier.
2. A work platform assembly as claimed in claim 1, in which the second crossmember has at its end opposite to the first leg a third fitting connectable to the upper end of the integral upward extension for supporting the second crossmember thereon.
3. A work platform assembly as claimed in claim 1, in which the second crossmember has at its end opposite to the first leg a third leg for supporting the second crossmember on the first work platform.
4. A work platform assembly as claimed in claim 3, in which the third leg is permanently fixed to the second crossmember.
5. A work platform assembly as claimed in any preceding claim, in which the second leg is permanently fixed to the second crossmember.
6. A work platform assembly as claimed in any of claims 1-4, in which the second leg is removably attached to the second crossmember and comprises or is interchangeable with one of the removable posts.
7. A work platform assembly as claimed in any preceding claim, in which the first leg is permanently fixed to the second crossmember.
8. A work platform assembly as claimed in any of claims 1-6, in which at least a portion of the first leg is removably attached to the second crossmember.
9. A work platform assembly as claimed in claim 8, in which the removably attached portion of the first leg comprises, or is interchangeable with, one of the removable posts.
10. A work platform assembly as claimed in any of claims 1-3, in which both the first and the second leg are permanently fixed to the second crossmember.
11. A work platform assembly as claimed in claim 8, in which the integral upward extension, removable post, removably attached portion of the first leg and the second leg are of substantially equal length.
12. A work platform assembly as claimed in claim 2 or 3, in which the first leg is longer than the removable post, and the third fitting or third leg (as applicable) is correspondingly elongated.
13. A work platform assembly as claimed in any preceding claim, in which a kickboard retaining bracket extends upwardly from the second crossmember, inboard of the second leg.
14. A work platform assembly as claimed in any preceding claim, in which an overhanging end of the second work platform is supported by an anti-flip bracket fitted to the second crossmember of the height extension arrangement adjacent to that end.
15. A work platform assembly as claimed in any preceding claim, in which an end of the second work platform is supported above the first work platform and an access staircase is fitted between the first platform and the second platform.
16. A work platform assembly as claimed in claim 15, in which the access staircase is supported by an anti-flip bracket at the end of the second work platform supported above the first work platform.
17. A work platform assembly as claimed in claim 15 or 16, in which the access staircase is fitted with a safety gate at the corresponding end of the second work platform.
18. A work platform assembly as claimed in any preceding claim, further comprising a bracket supported cantilevered from the integral upward extension, fixed or removable post, or first or second leg, and having an outboard end to which one or more of the generally horizontal rails is/are removably attached.
19. A work platform assembly as claimed in any preceding claim, further comprising a removable bracket for removably securing a toeboard to one of the removable posts.
20. A work platform assembly as claimed in any preceding claim, further comprising one or more diagonal braces secured between adjacent ones of the height extension arrangements.
21. A work platform assembly as claimed in any preceding claim, in which one or more of the generally horizontal rails fitted between adjacent ones of the height extension arrangements and/or fitted between the corresponding integral upward extensions are of a fixed length.
22. A work platform assembly as claimed in any preceding claim, further comprising a temporary guard rail used during set-up of the work platform assembly, the temporary guard rail comprising a pair of opposed ends each having a respective depending spigot removably receivable in an upper end of one of the removable posts or in an upper end of one of the integral upward extensions, the temporary guard rail further comprising a laterally offset central portion.