The present invention relates to a scaffold-board anti-lift device, and particularly but not necessarily exclusively to a scaffold-board anti-lift device for use in scaffolding against a building. Scaffolding is often required when erecting or repairing buildings, having a series of vertical, horizontal and lateral scaffold tubes. The lateral tubes, typically referred to as transoms, are positioned perpendicularly to two parallel spaced apart horizontal tubes, known as ledgers. The transoms interconnect the vertical tubes, known as standards, and ledgers. The plurality of scaffold tubes are secured together using scaffold clamps or couplers, and base plates are provided at the base of the standards to provide support to the scaffold structure.

One or more scaffold boards are installed on the scaffold structure, a longitudinal extent of each scaffold board being supported by the plurality of spaced apart transoms extending between two parallel ledgers. The scaffold boards provide a scaffold platform above the ground to support people and materials. Other scaffolding components, such as toe boards, guard rails, and cross and diagonal bracing, are often used to enhance safety when using scaffolding.

One problem that faces users is that the scaffold boards are not tied down to the scaffold structure. It is known for the scaffold boards to be lifted away from the ledgers unintentionally, for example in windy weather conditions or if the two ledgers underneath the scaffold platform are not perfectly in parallel or horizontal. This is a safety hazard for the users the scaffold platform is supposed to support, as the users may lose their balance or be injured by the scaffold board. Furthermore, any material dislodged by such an unstable scaffold board, and/or the unstable scaffold board itself, may cause injuries to personnel underneath the scaffold platform.

The present invention therefore seeks to provide a solution to one or more of the abovementioned problems.

According to a first aspect of the present invention, there is provided a scaffold-board anti-lift device comprising a single clamp element for releasably clamping the device to a scaffold tube, and an elongate rigid board-retaining element for preventing or limiting unintentional lifting of one or more scaffold boards, the board-retaining element being cantilevered from the clamp element at its proximal end, and having a uniform or substantially uniform lateral cross-section along at least a majority of its longitudinal extent from its distal end, so as to in use extend across an upper surface of said one or more scaffold boards a longitudinal axis of the board-retaining element being perpendicular or substantially perpendicular to a longitudinal axis of the clamp element, so as to in use extend across a lateral extent of said one or more scaffolding boards and a lateral axis of the board-retaining element being parallel or substantially parallel to a lateral axis of the clamp element.

The scaffold-board anti-lift device is advantageous due to the elongate rigid board- retaining element being attached to the clamp element, which is clamped to a scaffold tube of the scaffold structure. Therefore, the board-retaining element can retain one or more scaffold boards to the scaffolding, so that they will not or substantially not lift away from the scaffold tubes structure unintentionally. It improves stability of the scaffold platform formed by the one or more scaffold boards, thus improving safety for the users on the scaffold platform and personnel underneath, as users are less likely to trip over loose or misplaced scaffold boards or slip, and materials on the platform are less likely to be dislodged unintentionally. The device therefore improves the overall safety of users using such scaffolding.

The board-retaining element is uniform or substantially uniform lateral cross section, thus is unobtrusive when installed on the scaffold structure and does not cause an obstruction to users on the scaffold platform. Furthermore, the board-retaining element is rigid so that it maintains its shape even upon impact. Preferable and/or optional features of the invention are set forth in claims 2 to 16.

According to a second aspect of the invention, there is provided a method of preventing or limiting unintentional lift of one or more in use scaffold boards using a scaffold-board anti-lift device according to the first aspect of the invention, the method comprising the step of providing a rigid elongate board-retaining element fastened to a supporting scaffold structure, so as to extend laterally across an upper surface of the or each scaffold board. According to a third aspect of the invention, there is provided a method of preventing or limiting unintentional lift of one or more in use scaffold boards, the method comprising the step fastening a scaffold-board anti-lift device to a supporting scaffold structure, such that a rigid elongate board-retaining element extends laterally across an upper surface of the or each scaffold board.

According to a fourth aspect of the invention, there is provided a scaffold-board anti- lift device comprising a clamp element for releasably clamping the device to a scaffold tube, and an elongate rigid board-retaining element for preventing or limiting unintentional lifting of one or more scaffold boards, the board-retaining element being cantilevered from the clamp element at its proximal end, and having a uniform or substantially uniform lateral cross-section along at least a majority of its longitudinal extent from its distal end, so as to in use extend across an upper surface of said one or more scaffold boards.

For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which:

Figure 1 shows a perspective side view of one embodiment of a scaffold-board anti- lift device, in accordance with the invention;

Figure 2 shows a lateral cross sectional view of a scaffold structure with the scaffold- board anti-lift device of Figure 1 clamped thereto; and

Figure 3 shows a diagrammatic perspective view of the scaffold-board anti-lift device of Figure 1 clamped to the scaffold structure.

Referring to Figures 1 to 3, there is provided a first embodiment of an in use scaffold- board anti-lift device 10 releasably clamped to a scaffold structure 12. The scaffold structure 12 typically comprises a variety different scaffold tube types, including a plurality of standards 14, ledgers 16, and transoms 18. As shown in Figures 2 and 3, the scaffold tubes are typically arranged such that a plurality of pairs of spaced apart standards 14, each pair comprising an outer standard 14a and inner standard 14b, are positioned spaced apart along a wall of a building or structure requiring scaffolding. A pair of parallel spaced apart ledgers 16, the pair comprising inner and outer ledgers 16a, 16b, are positioned part way along a length of the standards 14 and are secured thereto using conventional scaffold clamps or couplers 20, such as a pressed steel or drop forged double coupler having two jaws for receiving the standard 14 and ledger 16 respectively. Transoms 18 are secured to the standards 14 and/or ledgers 16 by conventional scaffold clamps or couplers 20, such as a pressed steel or drop forged single coupler, to secure the scaffold tubes with each other.

Although not shown, other conventional scaffolding components, such as guard rails or bracing, may also be provided on the scaffold structure 12.

A plurality of scaffold boards 22 having an upper surface 24 and a lower surface 26 are positioned onto and supported by the transoms 18. The boards 22 are positioned between the two rows of spaced apart standards 14, thereby forming a platform 28 for supporting users, equipment and/or materials. A toe board 30 is preferably provided, positioned perpendicularly to the scaffold boards 22 and abutting the outer standards 14a.

Referring now to the scaffold-board anti-lift device 10, shown in detail in Figure 1, the device 10 comprises a clamp element 32 for releasably clamping the device to a scaffold tube, typically being an inner ledger 16a, and an elongate rigid board- retaining element 34 for preventing or limiting unintentional lifting of the scaffold boards 22.

The clamp element 32 includes a jaw 36 that is similar to a jaw of a conventional scaffold clamp 20, the jaw 36 having a first and second arm 38, 40 that are pivotally connected by a hinge 42, and a releasable clamping means 43. Each of the arms 38, 40 has a scaffold tube contacting surface 44, 46 and an outward facing surface 48, 50. Each of the scaffold tube contact surfaces 44, 46 is preferably part circular adjacent its proximal end, for receiving and clamping around a circumference of the inner ledger 16a.

The releasable clamping means 43 includes a bolt or elongate screw-threaded shaft 52 pivotally attached to the first arm 38, adjacent or proximate a distal end of the scaffold tube contacting surface 44, and a nut 54 rotatably engaged with the shaft 52 proximate its distal end. A slot 56 is provided at a distal end of the second arm 40 to allow the shaft 52 to extend through, such that the nut 54 on the shaft 52 is positioned at or adjacent to the outward facing surface 50 and thus anteriorly of the second arm 40.

The jaw 36 is openable and closable by pivoting the first and second arms 38, 40 about the hinge 42, such that the inner ledger 16a may fit therethrough and be clamped therein. The jaw 36 can be closed by turning the nut 54 on the shaft 56, so as to pull the two arms 38, 40 towards each other, until the device 10 is clamped fixed securely to the inner ledger 16a.

Other fastening means may also be considered, alternatively or additionally to that described above, such as an over-centre claps or toggle mechanism.

The elongate rigid board-retaining element 34 has a proximal end 58 and a distal end 60. The board retaining element 34 extends outwardly from adjacent a distal end of the outward facing surface 48 of the first arm 38. In other words, the board-retaining element 34 is cantilevered from the clamp element 32 at its proximal end 58. The board-retaining element 34 has a uniform or substantially uniform lateral cross section along at least a majority of its longitudinal extent from its distal end 60. In the embodiment illustrated in the figures, the whole longitudinal extent of the board- retaining element 34 has a uniform lateral cross section.

The board-retaining element 34 is, in this case, rectilinear or straight and is preferably permanently fixed to or integrally formed with the clamp element 32 to maximise rigidity of the board-retaining element 34.

The board-retaining element 34 preferably has a planar or substantially planar scaffold-board facing surface 62 and an upper surface 64 having an arcuate profile along its lateral extent. The board-retaining element 34 is spaced from the proximal ends of the arms 38, 40 of the jaw 36, such that when the clamp element 32 is engaged with the inner ledger 16a, the board-retaining element 34 is spaced away from the inner ledger 16a and is positioned to extend across the upper surface 24 of the plurality of scaffold boards 22. Preferably, in use, the board-retaining element 34 is positioned such that its scaffold- board facing surface 62 abuts or is closely adjacent to the upper surface 24 of the plurality of scaffold boards 22. The planar or substantially planar profile of the scaffold-board facing surface 62 is therefore advantageous as it maximises area of contact between the scaffold boards 22 and the device 10.

The board-retaining element 34 is preferably positioned on the device 10 such that its longitudinal axis is perpendicular or substantially perpendicular to a longitudinal axis of the clamp element 32, so as to in use extend across a lateral extent of the scaffold boards 22. A lateral axis of the board-retaining element 34 is preferably parallel or substantially parallel to a lateral axis of the clamp element 32.

A width of the board-retaining element 34 is preferably greater than its height, such that the board-retaining element 34 has a low or slim-line profile, so as to not cause an obstruction to the users on the scaffold platform 28.

The board-retaining element 32 is preferably made of the same material as the clamp element 32, typically galvanised steel or other material with suitable degree of strength and rigidity, and/or may be preferably cast or forged. However, it may be feasible that the board-retaining element is formed of a durable hard rubber and/or plastics.

To further increase durability of the device, the board-retaining element 32 is preferably provided with a protective layer or cover 66, typically made of rubber or other suitable durable weather-proof material, such as plastics. Information or other indicia may be printed and displayed on the protective cover 66.

The protective cover 66 may advantageously have one or more fluorescent portions (not shown) provided thereon to serve as illuminating means and/or a warning sign when natural lighting is inadequate. This may be achieved by impregnating the protective cover 66 with a fluorescent dye, or fluorescent paint may be applied to the protective cover or directly on the board-retaining element 34. Any other suitable light emitting means may also be considered, providing the means is suitably robust.

Illuminating means (not shown) may preferably be provided on the board-retaining element 34, for example along its longitudinal extent. Such illuminating means may be LEDs or other suitable weather proof illuminating means. In use, the scaffold structure 12 is first erected in the usual manner, where a plurality of scaffold boards 22 and the toe board 30 are supported by a plurality of standards 14, ledgers 16 and transoms 18. The board-retaining element 34 of the device 10 is positioned across the upper surface 24 of the scaffold boards 22 to extend laterally thereof. The clamp element 32 of the device 10 is opened to allow the jaw 36 to receive a portion of the inner ledger 16a and then closed using the releasable clamping means 43 to clamp around the inner ledger 16a. The board-retaining element 34 therefore extends across the scaffold boards 22 from adjacent to the inner ledger 16a towards the outer ledger 16b and the toe board 30. The length of the board-retaining element 34 is preferably sized such that its distal end 60 abuts the toe board 30, the board-retaining element 34 thereby also serving as a toe-board abutting or retaining means.

Alternatively, if multiple toe boards 30 are provided in order to cover the whole longitudinal extent of the scaffolding, then the board-retaining element 34 may be longer in length and the device 10 may be positioned such that the distal end 60 of the board-retaining element 34 extends outwardly of the scaffold structure 12, between two adjacent toe boards 30. In yet another alternative, the device 10 may be positioned between two toe boards 30, such that the clamp element 32 is arranged to clamp to the outer ledger 16b and the board-retaining element 34 extends towards the inner ledger 16a.

Thus, the device 10 can be used to prevent or limit unintentional lifting of the scaffold boards 22 by providing the rigid elongate board-retaining element 34 fastened to the supporting scaffold structure 12, so as to extend laterally across the upper surface 24 of each scaffold board 22. The scaffold-board anti-lift device is beneficial as it prevents or limits unintentional lifting of one or more scaffold boards, effectively retaining the scaffold boards to the supportive scaffold tubes therebelow. This dramatically reduces the likelihood of users tripping or slipping over loose boards, or materials or equipment falling from the scaffold platform unintentionally. The device enhances the structural integrity and stability of the scaffold structure, thus improving safety for users on the scaffolding and also personnel under the scaffold platform. It will be appreciated that although multiple scaffold boards are shown to be used in the embodiment illustrated in the figures, only a single scaffold board may be used and the scaffold-board anti-lift device may still be used in the same manner. Furthermore, it is typical of a scaffold structure to be provided with multiple scaffold platforms, and the device may be used on one or more scaffold platforms on a scaffold structure.

It is advantageous to use more than one device on a scaffold platform, as shown in Figure 3 where the devices are positioned spaced apart along the length of the platform, so that the scaffold boards are retained to the scaffold tubes at multiple positions along their longitudinal extents. However, it will be appreciated that only one device may be used, if preferred or required.

It will be appreciated that the device may be arranged to clamp to a standard rather than a ledger. In such an arrangement, the board-retaining element may be arranged such that the lateral axis of the board-retaining element is perpendicular or substantially perpendicular to the lateral axis of the clamp element, such that the scaffold-board contacting surface of the board-retaining element still faces the scaffold boards.

Furthermore, whilst a single clamp element is disclosed, it may be preferable to provide multiple clamp elements, adjacent to each other or at opposing ends of the board-retaining element.

It will also be appreciated that the board-retaining element may be releasably and/or removably fixed to the clamp element, for example by bolting, so that the orientation of the board-retaining element may be adjusted. This is particularly useful if the device is to be arranged to be suitable for clamping on a standard and a ledger. The board-retaining element may have a triangular cross section, in other words the upper surface having an apex along its lateral extent, rather than an arcuate upper surface as illustrated in the embodiment shown in the drawings. The apex may also be positioned along a central longitudinal axis of the board-retaining element. In yet another alternative, the cross section of board-retaining element may be provided in a shape other than a triangular shape, for example, an oblong or rectangular shape.

Edges of the board-retaining element may preferably be chamfered, so as to help dissipate force unintentionally impacted upon it, for example, by a user, thus reducing the likelihood of the user tripping over the device.

It will be appreciated that the protective cover on the board-retaining element may be dispensed with to reduce manufacturing costs.

The words 'comprises/comprising' and the words 'having/including' when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components, but does not preclude the presence of addition of one or more other features, integers, steps, components or groups thereof.

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of this invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

The embodiments described above are provided by way of examples only, and various other modifications will be apparent to persons skilled in the field without departed from the scope of the invention as herein described.