GB2449559A

GB2449559A - Scaffold guard

Info

Publication number: GB2449559A
Application number: GB0809387A
Authority: GB
Inventors: Melvyn Stephenson
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-05-24
Filing date: 2008-05-23
Publication date: 2008-11-26
Anticipated expiration: 2028-05-23
Also published as: GB2449559B; GB0809387D0

Abstract

A structure, especially for an elevated platform structure such as a scaffolding platform, comprising a rigid planar generally rectangular sheet 2; a plurality of apertures 6 disposed across the sheet in a two dimensional array, for example in a square array; engagement means 8 adapted to engage a sheet to a support such as a scaffolding pole and/or to another sheet in use. The apertures may be elongate in one direction and may be formed as a closed curve without corners. The sheet may be manufactured from a rigid polymeric plastic. The engagement means may be removable.

Description

GUARD

The invention relates to a side guard for a temporary or permanent structure of the sort delineated by a guard rail for example to define a pathway and especially a platform structure such as a scaffolding platform or like elevated platform structure.

Temporary and permanent walkway structures such as platform structures, and for example elevated structures, find a variety of applications, especially in construction. Scaffolding alongside a building or the like conventionally consists of a scaffolding framework that serves as a support for boards forming a platform or walkway and provides a safety rail typically at about waist height above the boards. This basic structure is open at the sides, and at least two further safety features are usually provided to deal with this.

First, a further wooden board, often referred to as a "toe board", is set vertically along the outer edge of the walkway. Second, a scaffolding guard may be hung from the safety rail to cover the gap between the safety rail and the toe board. The present invention lends itself particularly to the provision of a side guard for a scaffolding or similar platform structure, but it will be appreciated that the principles can be applied to any structure having a guard rail, including for example ground level walkways.

Conventional scaffolding guards comprise a generally planar screen of wire and/ or polymer mesh or fabric. The guard may include rail attachments to enable the guard to be hung vertically from the safety rail in use. A typical guard and toe board is described in US Patent 4928929.

Mesh web guards are not without disadvantages. The mesh construction leaves holes through which small debris could still penetrate and cause injury. Steel wire welded constructions can be difficult to manufacture, store and handle. They are prone to tangling and creasing and hence to damage during storage. Extruded polymer mesh structures have been suggested as alternatives but these lack durability and are typically only suited to single use. All flexible structures, and particularly polymer mesh and fabric structures, require care to ensure they remain vertical and effective in situ, especially over time and in windy conditions.

GB2423329 proposes in the alternative a more rigid polymeric panel guard. However, such guards can be of limited practical use, as the complete sheet panel is likely to cause problems on site, for example in windy conditions, when it is liable to be caught by gusts of wind and blown likeasail.

A guard structure is desired which mitigates some or all of the above disadvantages with prior structures.

According to the invention in a first aspect, a side guard for a structure, especially for an elevated platform structure such as a scaffolding platform, comprises: a rigid planar generally rectangular sheet; a plurality of apertures in the form of through holes disposed across the sheet in a two dimensional array and for example a square array; engagement means adapted to engage a sheet to a support such as a scaffolding pole and/ or to another sheet in use.

The basis of the invention is a sheet structure which is much more rigid in practice than the mesh and fabric structures known generally in the prior art. It is rigid to the extent that it remains essentially flat and does not ripple or flap in typical use conditions, for example in the wind, and to the extent that it essentially stores flat when not in use. It does not snap, does not crease, does not fall apart and does not get tangled up like a mesh type brick guard such as is exemplified in US4928929. It is robust, heavy duty and reusable. However, the holes in the sheet allow wind in windy conditions to blow through and reduce the tendency for the rigid sheet to act as a sail and be caught in a gust and blown free or otherwise rendered ineffective. The holes in the sheet may also serve as a location for a means to effect engagement between the sheet and a support such as a scaffolding tube and also as a location for a means to effect engagement between two sheets.

The apertures or holes provided in and through the planar sheet are disposed across the sheet surface in a two dimensional array, and for example a square array. Although it is not necessary that holes are arrayed across the entire surface area of the sheet, they are preferably arrayed across at least a major part of its surface area, to allow air to pass sufficiently through the sheet when it is hanging in situ that wind effects are reduced or minimised.

In a convenient embodiment, some or all of the apertures or holes in the array are identically shaped to each other. Similarly, some or all of the holes in the array are preferably identically sized.

Preferably, an aperture in the sheet is elongate in one direction, and particularly preferably is elongate in a direction corresponding to a vertical direction as defined in use (and for example with reference to the engagement means which may inherently define a use direction).

Preferably, an aperture forms a closed curve, that is, it is formed without corners. Preferably, such a closed curve is elongate, especially as indicated in a vertical direction. Preferably, the elongate curve comprises an elliptical shape or a shape having parallel sides and terminated at either end by an arc, and for example by a semicircle.

Preferably each aperture has a narrowest dimension of at least 20mm.

Preferably in the case of an elongate aperture having a narrower extent in one direction and a wider extent in another direction each aperture has a maximum dimension in a narrower direction, for example a horizontal direction, defined as in use, of no more than 50mm, so that the apertured structures may not be used as an aid to climbing. A horizontal direction is for example a narrower direction of an elongate shaped aperture.

Dimensions in the elongate direction, preferably the vertical direction as defined in use, may be 100-200mm.

Although it is preferable that apertures are arrayed across at least a major part of the surface of the planar sheet, in a preferred embodiment a portion or portions of the sheet may be unapertured. In particular, an unapertured portion may be left generally at the centre of the sheet. An unapertured portion may have a function for example to carry information, such as advertising, makers logos or the like, or instructional or warning notices. Preferably, any single unapertured portion is square or rectangular, and is no greater than 500mm by 500mm in extent.

The sheet material of the guard of the invention is sufficiently rigid that it may be stored flat without creasing and folding, and so that it will not ripple or flap to any substantive extent out of planar state in windy conditions in use. Material selection and thickness are suitable to achieve this. Suitably for example, the sheet is manufactured from a sufficiently rigid polymeric plastics material.

In a preferred embodiment, the sheet is manufactured as a single monolithic structure. Engagement means may be separately fabricated, and may for example be detachable as set out below. Preferably, the monolithic structure is fabricated as a single piece extrusion. The necessary apertures may be integrally formed or subsequently created in the sheet by stamping, machining or other suitable process. Preferably, the engagement means, even where separately fabricated and detachable, comprise the same plastics material as the material of the sheet.

The side guard of the invention is particularly suited to use as a scaffolding guard in familiar manner. Preferably, the side guard is adapted for use with a toe guard structure or includes an integral unapertured bottom edge portion to act as such a toe guard structure in use.

The engagement means of the invention preferably at least comprises a means to engage the sheet in position on a platform support such as a scaffolding pole. Additionally or alternatively the engagement means may comprise means to engage several sheets together, for example vertically together to form a guard structure of greater vertical extent than an individual guard means. Suitable engagement means may comprise hooks or ties to engage around a platform support pole in use. In a particularly preferred embodiment an engagement means comprises at least one hook, and preferably at least a pair of hooks for stability, adapted to engage upon a platform support pole in use. Particularly conveniently this will be a generally horizontal support pole such as a scaffolding guard rail or similar, from which the planar sheet will then hang vertically as a side guard.

Conveniently, such a hook is additionally so sized and shaped that it may also penetrate and engage with the openings in the sheet, so as to engage a pair of sheets together. Additionally or alternatively, specific and bespoke sheet connection means may be provided which penetrate and effect an engagement between apertures in respective sheets for this purpose.

In a preferred embodiment, for convenience of manufacture and/ or storage, an engagement means is removable. For example, an engagement means is structured to be releasably engageable in an aperture of the sheet. For example, an engagement means includes an engaging formation shaped to pass through the aperture in a first, attachment configuration and in particular in a first attachment position, but to engage with and retain the engagement means in position in the aperture in a second, connected position, and in particular in the second direction, corresponding to a use direction.

For example, an engaging formation is structured such that a twist and lock action can be effected, in that in a first attachment position, where an engaging formation is presented at a first orientation and for example at an angle to its intended use position, the engaging formation can penetrate and be passed through an aperture in the screen member, but in a second connected position where an engaging formation sits at a second orientation at an angle thereto, and for example at 900 thereto, conveniently corresponding to a use orientation, the engaging formation is securely retained within the aperture fixing the engagement means in a connected position.

Conveniently to effect this, the engaging formation comprises a planar structure which may be generally or at least partly complementarily shaped to the aperture, a body including an attachment formation such as a hook, and a neck portion therebetween. To attach via a twist and lock action, the engaging formation is passed through an aperture in a suitable orientation, the entire engagement means is twisted, and as a result the engagement means is then retained in position in the aperture with the engaging formation on one side of the sheet no longer oriented to be able to pass through the aperture and the body portion disposed on the other side of the sheet.

A detachable engagement means may include a lip projection remotely spaced from the primary engaging formation to retain and lock the whole structure in position when the engaging formation is in its connected position, for example by bearing against an upper edge of the sheet and! or and edge of a second aperture therein.

In accordance with this preferred embodiment, both manufacture and storage of the sheet are made much more practical, as the hooks or other engagement means can be fabricated separately.

The sheet is suitably sized and shaped for the envisaged application. For example, for application as a scaffolding guard, a height of between 750mm and 1500mm and a width of between 750mm and 200mm are likely to be convenient. The sheet is preferably generally square or rectangular, although rounded corners are likely to be particularly advantageous even given such a general shape and should not be considered excluded.

The invention will now be described by way of example with reference to figures 1-5 of the accompanying drawings, in which: -figure 1 is an isometric projection of an embodiment of guard in accordance with the invention; -figure 2 is the guard of figure 1 in plan view; -figure 3 illustrates in plan view the attachment of a detachable hook; -figure 4 is an isometric projection of a detachable hook, -figure 5 is a side view of a detachable hook.

Referring first to figures 1 and 2, a guard in accordance with an embodiment of the invention comprising a rigid plastic sheet with a pair of detachable hooks is illustrated, respectively in isometric projection and in a plan view from the front (as defined with reference to use). The guard is envisaged for use as a side guard for a temporary or permanent platform structure such as a scaffolding platform on which it will hang in a generally vertical orientation.

The main body of the structure is a sheet 2 of relatively rigid polymeric material, in the embodiment high-grade polypropylene (PP). This gives reasonable durability with reasonable ease of manufacture. To increase the effective lifetime of the guard the material of the sheet is enhanced by incorporation of UV stabilisation and flame retardant compounds during the manufacturing process in familiar manner. The structure as so fabricated intended to offer a long safe working life in outdoor conditions in all weathers and across all industries whether used on temporary or permanent structures.

A further advantage of the sheet plastics material is that it can be coloured, for example to stand out as a safety feature or for presentational or advertising purposes, and in the embodiment the sheet is also provided with an unapertured central portion 4 which can carry a notice, an advert, a company logo etc. Provided the unapertured portion is kept to a relatively minor extent of the overall area, this does not unduly affect the ability of the sheet to accommodate wind.

The size of the sheet 2 may vary depending upon application. A typically envisaged height might be 0.76m, for example for temporary access platforms, or 0.91 m for permanent structural steel platforms. A particular envisaged application of the embodiment of the invention is as a scaffolding brick guard, hanging from a scaffolding hand rail. Scaffolding hand rails at present are typically located at a height of between 0.91 m and 1.1 5m, and a guard of this size can be used effectively on all such scaffolding hand rails. In the illustrated embodiment, a width of I.17m is envisaged.

The material of the sheet 2 is of sufficient thickness to give the necessary rigidity. In the embodiment, the polypropylene sheet is 4mm thick. As a result, a guard in accordance with the embodiment weighs around 2- 2.5kg. This gives adequate durability and rigidity. It is worth noting that the product can as a result be expected to cause less damage than a comparable steel brick guard were it to fall off a scaffold onto a person below for instance.

The guard is provided with a plurality of apertures 6 arrayed in a square array across the surface of the sheet except in the unapertured portion 4.

These are elongate in a vertical direction, with a maximum width of 50mm so that they can not be used for climbing. Apertures in the example embodiment are around 100mm in height and are shaped with parallel sides in the elongate direction and semicircular ends. Both the shape of the ends and the narrow width in the example embodiment discourage abuse of the apertures as a foothold and hence abuse of the sheet as a climbing aid.

In the envisaged use of the embodiment as a scaffolding side guard or brick guard the sheet is engaged in position upon a scaffolding guard rail by means of the engagement means 8 which hook over the rail. The sheet thereby hangs vertically down between scaffolding guard rail and platform. The engagement means 8 in the illustrated embodiment are detachable, for example for storage, being attached to the sheet 2 by retention of an engaging portion 10 which has been inserted into an aperture 6.

The detachable engagement means and its means of attachment are shown in greater detail in figures 3 to 5. Figure 3 illustrates a first engagement means in a connection position and orientation and a second engagement means in an insertion position and orientation ready for attachment with the sheet. The sheet is in plan view. Figure 4 represents an isometric projection and figure 5 a side view of the engagement means in more detail.

Each engagement means comprises a hook portion 12 which, when attached to the sheet, effects the engagement of the assembled whole over and upon a scaffolding pole, and thus allows the sheet 2 to hang vertically in use, and a shank portion 14 which includes the engaging formations by which the hook is engaged to the sheet. These engaging formations take the form of the primary engaging plate structure 10 and a secondary locking lip 13.

The main engaging plate 10 conveniently generally corresponds in shape to an aperture 6, as illustrated, or at least has generally comparable extent in both a longitudinal and transverse direction. More generally, the engaging plate 10 or similar engaging formation co- operates with an elongate aperture at least in that it has a longitudinal extent that is greater than a transverse extent of the aperture but lesser than a longitudinal extent of the aperture so as to be insertabte into the aperture in a first orientation but not in a second.

To attach an engagement means, the engagement means is brought to the sheet in a horizontal orientation so that the plate 10 corresponds directly to an aperture 6, in the manner shown by the unattached engagement means on figure 3. The plate 10 can then be inserted through an aperture 6. The entire engagement means is then rotated through 900 to sit in a vertical orientation, as illustrated by the attached engagement means on the left of figure 3. In this orientation, the engaging plate 10 sits on one side of the sheet 2, and the shank portion 14 sits on the other side, linked by a neck portion 11. The engagement means cannot readily be removed in this orientation because the plate 10 now extends to a greater extent in a width direction than the aperture 6.

The whole engagement means is stabilised and locked by engagement of the secondary locking lip 13. In the illustration this lip 13 is shown engaged upon a top edge of the sheet 2. Alternative configurations could be envisaged. For example, a locking means could be envisaged which locked in position in a second aperture, remotely spaced from, and for example immediately above or below, an aperture through which the plate had been inserted and engaged.

In accordance with the invention, particularly in this indicated embodiment, a product is developed which will offer a number of potential advantages over prior art brick guard designs, especially of the mesh type. A structure is robust and much less prone to damage. It does not tangle or break during storage. It can be coloured, and provided with logos or messages, to improve appearance, as a safety feature, or for advertising. The removable hooks in the preferred embodiment aid manufacture and are convenient for storage, and to maximise flexibility during use.

Claims

1. A side guard structure, comprising: a rigid planar generally rectangular sheet; a plurality of apertures disposed across the sheet in a two dimensional array and for example a square array; engagement means adapted to engage a sheet to a support such as a scaffolding pole and/ or to another sheet in use.

2. A structure in accordance with claim I wherein the apertures are arrayed across at least a major part of the surface area of the sheet.

3. A structure in accordance with claim I or 2 wherein some or all of the apertures in the array are identically shaped and/ or identically sized.

4. A structure in accordance with any preceding claim wherein an aperture in the sheet is elongate in one direction.

5. A structure in accordance with claim 4 wherein an aperture in the sheet is elongate in a direction corresponding to a vertical direction as defined in use.

6. A structure in accordance with any preceding claim wherein an aperture forms a closed curve without corners.

7. A structure in accordance with claim 6 wherein such a closed curve is elongate in a vertical direction and comprises a shape having paraflel sides and terminated at either end by an arc, and for example by a semicircle.

8. A structure in accordance with any preceding claim wherein an aperture has a narrowest dimension of between 20mm and 50mm and a widest dimension of between 100mm and 200mm.

9. A structure in accordance with any preceding claim wherein an unapertured portion is provided generally at the centre of the sheet.

10. A structure in accordance with any preceding claim wherein the sheet is manufactured from a rigid polymeric plastics material.

11. A structure in accordance with any preceding claim including an integral unapertured bottom edge portion to act as a toe guard in use.

12. A structure in accordance with any preceding claim wherein the engagement means comprises at least one hook adapted to engage upon a support pole in use.

13. A structure in accordance with any preceding claim wherein the engagement means is removable.

14. A structure in accordance with claim 13 wherein the engagement means is structured to be releasably engageable in an aperture of the sheet.

15. A structure in accordance with claim 14 wherein the engagement means includes an engaging formation shaped to pass through the aperture in a first, attachment position, but to engage with and retain the engagement means in position in the aperture in a second, connected position.

16. A structure in accordance with claim 15 wherein the engaging formation is structured such that a twist and lock action can be effected, in that in a first attachment position, where an engaging formation is presented at a first orientation, the engaging formation can penetrate an aperture in the screen member, but in a second orientation at an angle thereto, and for example at 900 thereto, the engaging formation is securely retained within the aperture fixing the engagement means in a connected position.

17. A structure in accordance with claim 16 wherein the engaging formation comprises a planar structure complementarily shaped to the aperture, a body including an attachment formation, and a neck portion therebetween.

18. A structure in accordance with any one of claims 13 to 17 wherein a detachable engagement means includes a lip projection remotely spaced from a primary engaging formation to retain and lock the whole structure in position when the engaging formation is in its connected position, for example by bearing against an upper edge of the sheet and/ or and edge of a second aperture therein.

19. A structure in accordance with any preceding claim adapted for use as a scaffolding guard, and having a height of between 750mm and 1500mm and a width of between 750mm and 200mm.