GB2491193A

GB2491193A - Perimeter screen with rotating debris retainer

Info

Publication number: GB2491193A
Application number: GB1108994.3A
Authority: GB
Inventors: Mark Taylor
Original assignee: Harsco Infrastructure Services Ltd
Current assignee: Harsco Infrastructure Services Ltd
Priority date: 2011-05-27
Filing date: 2011-05-27
Publication date: 2012-11-28
Anticipated expiration: 2031-05-27
Also published as: GB2491193B; GB201108994D0

Abstract

A perimeter screen system 20 comprises a support structure 5 and at least one debris retainer 21. The support structure 5 is mountable to the edge 9 of at least two floors 8 of a construction for translation of the perimeter screen system with respect to the construction. The at least one debris retainer 21 is rotatably mounted to the support structure 5 and rotatable between an operation configuration and a retracted position (shown in Figure 3). In its operational configuration, the debris retainer 21 projects at least partially under the edge 9 of a floor 8 of the construction, to catch debris. In its retracted configuration the debris retainer is positioned away from the construction. A debris retainer device, a construction, and a method of operating a perimeter screen system are also claimed.

Description

Title: A Perimeter Screen System

Description of Invention

The present invention relates to a perimeter screen system, a debris retainer, a construction incorporating a perimeter screen system and a method of operating a perimeter screen system.

When forming the floors of a construction, it is known to use a perimeter screen system, which encloses the perimeter of at least a part of the construction. The system provides a safety screen, to safeguard workers from adverse weather conditions and to ensure a safe working environment. The system further comprises at least one platform, to support formwork and equipment for use in forming the next floor of the construction and/or to provide a useful work space for construction workers around the perimeter of the construction. As each floor of the construction is formed, the perimeter screen system is moved up the construction to provide a work space for the construction of the next floor; to surround the recently formed floor(s); and to expose the previously formed floors beneath. The previously formed floors are typically, by that point, provided with temporary edge protection or the final exterior cladding, window units etc. It is important to prevent, as much as possible, any tools and debris falling from the construction, which could otherwise cause injury to personnel beneath the construction. It is therefore preferable that the platforms of the perimeter screen system are arranged as close as possible to the adjacent floors of the construction, to prevent or at least limit any debris falling through the gap between the two. There is, however, inevitably always a slight gap, through which debris and tools may still pass.

To reduce the problem, it is known to retrofit panels and/or seals/gaskets to the edge of the platforms, to abut against the adjacent floor of the construction.

However, an effective seal is not guaranteed. Moreover, since the platform is normally slightly vertically offset with respect to an adjacent floor (see figure 1), such panels and/or seals/gaskets are usually angled with respect to the platform. As a result, the usable horizontal work space of the platform is reduced and, in any event, trip hazards are formed. Still further, such items are normally custom fitted for a particular construction, requiring an additional tradesperson and leading to wastage of material after completion of the construction.

Even when any gaps between the platforms and floors are substantially sealed, the possibility of debris being dislodged remains when the perimeter screen system is vertically translated with respect to the building.

Accordingly, the present invention provides a perimeter screen system comprising: a support structure mountable to the edge of at least two floors of a construction for translation of the perimeter screen system with respect to the construction; and at least one debris retainer rotatably mounted to the support structure and rotatable between: an operational configuration, in which the debris retainer projects at least partially under the edge of a floor of the construction, to catch debris; and a retracted configuration, in which the debris retainer is positioned away from the construction.

Preferably, the at least one debris retainer is rotatably mounted to a lower end of the support structure.

Conveniently, the at least one debris retainer comprises a debris tray and at least one support arm rotatably mounted to the support structure, the debris tray being generally perpendicular to the support arm.

Advantageously, the at least one support arm is rotatably mounted to the support structure at a point above the centre of gravity of the debris retainer.

Preferably, the debris retainer is selectively rotatable between the operational and retracted configurations.

Conveniently, when in the operational configuration, substantially half of the debris retainer projects under the edge of a floor of the construction.

Advantageously, the perimeter screen system further comprises a removable lever to rotate the at least one debris retainer with respect to the support structure.

Preferably, the rotational position of the at least one debris retainer with respect to the support structure may be selectively locked.

Conveniently, at least one debris retainer is provided with at least one bearing surface to engage with the edge of a floor of the construction to cause the debris retainer to be rotated away from the construction during upwards linear translation of the perimeter screen system with respect to the construction.

Advantageously, the perimeter screen system comprises a first safety screen secured to the support structure, remote from the construction, and a second safety screen secured to the at least one debris retainer, a respective edge of the first and second safety screens arranged to be adjacent one another.

The present invention further provides a debris retainer rotatably mountable to a support structure of a perimeter screen system, the support structure mountable to the edge of at least two floors of a construction for translation of the perimeter screen with respect to the construction, the debris retainer in use being rotatable between: an operational configuration, in which the debris retainer projects at least partially under the edge of a floor of the construction, to catch debris; and a retracted configuration, in which the debris retainer is positioned away from the construction.

The present invention further provides a construction comprising a plurality of floors; and incorporating a perimeter screen system comprising; a support structure mounted to the edge of at least two floors of the construction for linear translation of the perimeter screen system with respect to the construction; and at least one debris retainer rotatably mounted to the support structure and rotatable between: an operational configuration, in which the debris retainer projects at least partially under the edge of a floor of the construction, to catch debris; and a retracted configuration, in which the debris retainer is positioned away from the construction.

The present invention further provides a method of operating a perimeter screen system, the perimeter screen system comprising a support structure and at least one debris retainer rotatably mounted to the support structure, the method comprising: mounting the support structure to the edge of at least two floors of a construction and configuring the debris retainer in an operational configuration such that it projects at least partially under the edge of a first floor of the construction, to catch debris; rotating the debris retainer into a retracted configuration, wherein the debris retainer is positioned away from the edge of said first floor of the construction; translating the perimeter screen system vertically up the construction; and rotating the debris retainer into an operational configuration such it projects at least partially under the edge of a second floor of the construction, to catch debris Embodiments of the invention will now be described, by way of example only, with respect to the following figures, in which: FIGURE 1 illustrates a perimeter screen system according to the prior art; FIGURE 2 illustrates a perimeter screen system according to the present invention, in an operational configuration; FIGURE 3 illustrates a perimeter screen system according to the present invention, in a retracted configuration; FIGURE 4 illustrates the debris retainer of Figures 2 and 3.

Figure 1 illustrates a perimeter screen system 1 according to the prior art, comprising a support structure 2, to which platforms 3 and a safety screen 4 are attached. Preferably, the support structure 2 comprises a plurality of support rails 5 (only one visible in Figure 1), arranged vertically and parallel to one another, connected by reinforcing members 6 to the safety screen 4. The safety screen 4 also comprises a supporting structure.

The construction 7 comprises a plurality of floors 8. The edges 9 of the respective floors 8 collectively define a perimeter of the construction 7. It will be noted that the perimeter screen system 1 is mounted on the outside of the construction 7, so that workers can access the existing floors 8 and form new floors 8 during the construction process whilst standing on the platforms 3.

Mounting shoes 10 are secured to the completed floors 8 of the construction 7.

A support rail 5 is received between claws of a shoe 10, which retain and constrain the support rail 5 for vertical translation along the construction 7.

Preferably, there are at least two parallel support rails 5 of the perimeter screen system 1 mounted to the construction 7. As more floors 8 are formed and mounting shoes 10 are provided at the edges 9 of those floors 8, the perimeter screen system 1 can be translated up the construction 7 in a conventional manner.

As discussed earlier, it is possible for debris and tools to fall between a platform 3 and the adjacent floor 8 of the construction 7, both during static use and especially when the perimeter screen system 1 is being translated up the construction 7. Debris will tend to fall down the perimeter of the construction 7, between the edge 9 of the floor 8 and the perimeter screen system 1, potentially causing injury to personnel below. The distance between the edge of a platform 3 and the edge 9 of an adjacent floor 8 may be in the region of 300mm, to account for the size of the support rail 5 locked between the two. It is known to provide cut-outs in the platforms 3 to accommodate the support rails 5 and thus allow the edge of the platform 3 to be arranged closer to the floor 8, but a gap may still remain.

Accordingly, as shown in Figures 2 to 4, the perimeter screen system 20 according to the invention provides a debris retainer 21 rotatably mounted to the climbing rail. The debris retainer 21 is rotatable between an operational configuration (Figure 2), in which the debris retainer 21 projects under the edge 9 of a floor 8 of the construction; and a retracted configuration (Figure 3), in which the debris retainer 21 is positioned away from the edge 9 of a floor 8 of the construction 7. Only the lower end of the perimeter screen system 20 is shown in Figures 2 and 3. The upper part of the perimeter screen system 20 (not shown) may be substantially the same as that shown in Figure 1. It will be noted that the perimeter screen system 20 shown in Figures 2 and 3 comprises an additional safety screen 22 secured to the climbing rails 5 and the climbing rails 5 in Figures 2 and 3 differ in length to those shown in Figure 1.

The debris retainer 21 comprises a debris tray 23 and a pair of support arms 24 (see Figure 4). The debris tray 23 is generally perpendicular to the support arms 24 and comprises an additional rim 25 at the front edge. The rim 25 conveniently promotes the retention of debris in the tray 23 when the debris retainer is rotated into a retracted configuration. The support arms 24 are configured to be pivotably mounted about a point 33 at their upper ends to a lower part of a respective support rail 5.

In the embodiment shown, the support arm 24 is selectively rotatable with respect to the support rail 5, and the rotational position of the support arm 24 with respect to the support rail 5 may be selectively locked. The support arms 24 are each provided with a bore 26. When in the operational configuration, a pin may be passed through the bore 26 in the support arm 24 and a corresponding bore on the support rail 5. An end stop plate 27 is also provided, to prevent over-rotation of the debris retainer 21 and to ensure repeatable alignment between the two bores 26. When in the operational configuration, the debris retainer 21 is not intended for personnel to stand on but instead rests a short distance below the floor 8, preferably in the range of 300 -500mm.

The support arms 24 each comprise a lug 28 provided with a second bore 21.

When in the retracted configuration, the second bore 29 may be aligned with a bore on the support rail 5 and a pin inserted thereth rough, to lock the debris retainer 21 in the retracted configuration.

The position of the debris retainer 21 may be selectively locked by other suitable means, for example a clutch or brake mechanism.

A safety screen 30 is secured to the debris retainer 21 (shown in Figures 2 and 3). The upper edge of the safety screen 30 is positioned adjacent the lower edge of the safety screen 22 secured to the climbing rail 5, to prevent debris from passing between the two. As with the safety screen 22, the safety screen may comprise either a flexible or rigid mesh panel. Alternatively, either or both screens 22, 30 may comprise a solid panel or panels.

With the embodiment shown, rotation of the debris retainer 21 may be effected by a user releasably securing a lever 31 to the support arm. Conveniently, the user 32 may attach and operate the lever 31 from a safe position on the floor 8 of the construction 7, rather than having to be positioned on a lower, potentially unprotected, floor 8 and reach up to rotate the debris retainer 21 by hand. The lever 31 provides a suitable moment arm allowing the user 32 to rotate the debris retainer 21 into the required configuration.

Rotation of the debris retainer 21 may be powered, for example, by a hydraulic actuator. Preferably, the perimeter screen system 20 is a self-climbing screen system, in which hydraulic cylinders are used to translate the perimeter safety screen 20 with respect to the construction 7. In such embodiments, the control system may be configured such that the debris retainer 21 must first be rotated into a retracted configuration, clear of the construction 7, before the perimeter safety system 20 may be translated up the construction 7. Sensors may be incorporated to determine and/or verify the position of the debris retainer 21.

In the embodiment shown, the debris retainer 21 is mounted such that the centre of gravity is below the pivot point. Accordingly, the debris retainer 21 naturally rests at a position between an operational and retracted configuration.

In one embodiment, the mass of the support arms 24 may be configured to be significantly higher than that of the debris tray 23, such that the centre of gravity is close to the support arms 24. As such, the natural resting position of the debris retainer 21 will be substantially in the operational configuration.

In another embodiment, the debris tray 23, or a counterweight, could project from the other side of the support arm 24, such that the centre of gravity is in line with the support arm 24.

In one embodiment, the width (between the support arm 24 and rim 25) of the debris tray 23 is 600mm, such that the debris tray fills the 300mm gap between the platform 3 and floor 8 and then protrudes a further 300mm into the construction 7, under the floor 8.

In one embodiment, the support arm 24 may be urged into a predetermined configuration by a resilient biasing member, for example a spring. Accordingly, when the support arm 24 is rotated away from the predetermined configuration, the force of the resilient biasing member causes the support arm 24 to rotate back towards the predetermined configuration. Preferably, the debris retainer 21 is urged towards a operational configuration where the debris tray 23 protrudes under the edge of the floor 8, so that it fails safe'.

In another embodiment (not shown), the debris retainer is provided with at least one bearing surface to engage with the edge 9 of a floor 8 to cause the debris retainer to be rotated away from the construction 7 during linear translation of the perimeter screen system with respect to the construction. As such, the movement of the debris retainer into the retracted position may be automatic.

The bearing surface may be provided by a wedge shaped panel provided at one end (or both ends) of the debris tray. The panel and rim on the front of the debris tray therefore collectively present a debris retaining container.

When the debris retainer 21 is arranged between two adjacent floors 8 and in an operational configuration, the debris retainer 21 effectively prevents there being a clear line of sight between the edges 9 of the two floors 8. In the embodiments described above and shown in figures 2 and 3, the debris retainer 21 penetrates the perimeter of the construction 7, such that the debris retainer 21 is interleaved between adjacent floors 8. Preferably, the debris retainer 21 is configured such that it does not protrude so far into the construction 7 that it interferes with any edge protection, glazing panels, or any other structural items position near the edge of the construction 7. In another embodiment, the front of the debris retainer may not penetrate the perimeter as such but instead, when in the operational configuration, be co-planer with the respective edges 9 of the adjacent floor 8.

By preventing a clear line of sight between two adjacent floors 8, even if any falling debris does not remain within the debris retainer, it will at least deflect its path back into the construction 7, away from the edge 9 of the floor 8 below.

In one embodiment, a perimeter screen system may comprise a plurality of debris retainers, either individually or collectively rotatable. A flexible seal may be provided on the neighbouring edges of the plurality of debris retainers to limit any debris falling through any gap between adjacent debris retainers.

In one embodiment, a debris retainer may have retractable trays at either end.

To translate the perimeter screen system 20 vertically up a construction 7, the debris retainer 21 is initially in the operational configuration, projecting under the edge 9 of a floor 8. It must therefore first be rotated into a retracted configuration, wherein the debris retainer 21 is positioned away from the edge 9 of said first floor 8 of the construction 7. The perimeter screen system 20 may then translated vertically upwards. When in position, the debris retainer 21 is rotated back into the operational configuration.

When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

CLAIMS1. A perimeter screen system comprising: a support structure mountable to the edge of at least two floors of a construction for translation of the perimeter screen system with respect to the construction; and at least one debris retainer rotatably mounted to the support structure and rotatable between: an operational configuration, in which the debris retainer projects at least partially under the edge of a floor of the construction, to catch debris; and a retracted configuration, in which the debris retainer is positioned away from the construction.
2. A perimeter screen system according to any preceding claim, wherein the at least one debris retainer is rotatably mounted to a lower end of the support structure.
3. A perimeter screen system according to any preceding claim, wherein the at least one debris retainer comprises a debris tray and at least one support arm rotatably mounted to the support structure, the debris tray being generally perpendicular to the support arm.
4. A perimeter screen system according to claim 3, wherein the at least one support arm is rotatably mounted to the support structure at a point above the centre of gravity of the debris retainer.
5. A perimeter screen system according to any preceding claim, wherein the debris retainer is selectively rotatable between the operational and retracted configurations.
6. A perimeter screen system according to any preceding claim, wherein when in the operational configuration, substantially half of the debris retainer projects under the edge of a floor of the construction.
7. A perimeter screen system according to any preceding claim, further comprising a removable lever to rotate the at least one debris retainer with respect to the support structure.
8. A perimeter screen system, wherein the rotational position of the at least one debris retainer with respect to the support structure may be selectively locked.
9. A perimeter screen system according to any proceeding claim, wherein the at least one debris retainer is provided with at least one bearing surface to engage with the edge of a floor of the construction to cause the debris retainer to be rotated away from the construction during upwards linear translation of the perimeter screen system with respect to the construction.
10. A perimeter screen system according to any preceding claim, comprising a first safety screen secured to the support structure, remote from the construction, and a second safety screen secured to the at least one debris retainer, a respective edge of the first and second safety screens arranged to be adjacent one another.
11. A debris retainer rotatably mountable to a support structure of a perimeter screen system, the support structure mountable to the edge of at least two floors of a construction for translation of the perimeter screen with respect to the construction, the debris retainer in use being rotatable between: an operational configuration, in which the debris retainer projects at least partially under the edge of a floor of the construction, to catch debris; and a retracted configuration, in which the debris retainer is positioned away from the construction.
12. A construction comprising a plurality of floors; and incorporating a perimeter screen system comprising; a support structure mounted to the edge of at least two floors of the construction for linear translation of the perimeter screen system with respect to the construction; and at least one debris retainer rotatably mounted to the support structure and rotatable between: an operational configuration, in which the debris retainer projects at least partially under the edge of a floor of the construction, to catch debris; and a retracted configuration, in which the debris retainer is positioned away from the construction.
13. A method of operating a perimeter screen system, the perimeter screen system comprising a support structure and at least one debris retainer rotatably mounted to the support structure, the method comprising: mounting the support structure to the edge of at least two floors of a construction and configuring the debris retainer in an operational configuration such that it projects at least partially under the edge of a first floor of the construction, to catch debris; rotating the debris retainer into a retracted configuration, wherein the debris retainer is positioned away from the edge of said first floor of the construction; translating the perimeter screen system vertically up the construction; and rotating the debris retainer into an operational configuration such it projects at least partially under the edge of a second floor of the construction, to catch debris.
14. A debris retainer, construction or method substantially as hereinbefore described with reference to Figures 2 to 4.
15. Any novel matter or combination thereof described herein.