Background of the Invention Walking boards are commonly used to provide a support platform, walkway or pathway structure upon which users may negotiate an underlying surface. For example, walking boards are known for placement over roof structures of buildings to allow users to safely traverse the roof for inspection or maintenance purposes. Similarly, they may be laid over grassed areas to protect those areas from foot traffic or to allow users to safely traverse those areas free from mud, rocks and similar obstacles.

Traditionally, walking boards or duckboards have been manufactured in the form of a support frame which is covered with slats or battens on which users walk. These have the disadvantage of being relatively expensive to construct and are not always easily interconnected so as to provide the desired resulting walkway.

An example of a duckboard constructed from plastics materials is provided in British patent specification no. 2167335 in the name of H L Plastics Ltd. In that document plastic structural members are extruded and connected together to form individual board structures. Rigid sleeves are used to interconnect the boards end to end to form a flat walkway in the valley formed between intersecting sloping roof surfaces.

It is an object of the present invention to provide a walking board which allows a substantially continuous walkway or support structure to be provided.

An alternative object of the invention is to provide a walking board which can

be connected with other boards to provide a pathway or support structure that follows a contour of a surface or structure beneath which the walkway or structure is provided.

A further alternative object of the invention is to provide a walking board which at least ameliorates one or more disadvantages of existing constructions, or which will at least provide the public with a useful alternative.

Summary of the Invention In one aspect the invention consists in a walking board having an upper surface upon which a user may walk in use, a lower surface which is substantially opposite the upper surface, and sides generally bounding the upper and lower surfaces, each of the sides including one or more teeth thereon, the construction and arrangement of the teeth being such that a side of a further said walking board may be placed adjacent to any side of the walking board so that the one or more teeth on the respective sides intermesh whereby the upper surface of the walking board and the further walking board form a substantially continuous walking surface.

Preferably an engagement means is provided on at least one of the sides to allow the walking board to be engaged with the further walking board. The engagement means may allow a pivotal engagement to be formed between the walking board and the further walking board.

In a preferred embodiment the engagement means comprises an aperture provided in a tooth of each side, and an elongate engagement pin adapted to be received in the aperture whereby the engagement pin may be provided through apertures in teeth on the sides of the walking board and the adjacent walking board to interconnect the walking board with the further walking board.

The aperture is preferably provided substantially parallel to the side on which the tooth is located so that in use the walking board may pivot relative to the further walking board.

The elongate pin may be dimensioned so that in use an end of the elongate pin may projects from the walking board.

To provide structural strength, the lower surface may include one or more strengthening ribs. The upper surface preferably includes a plurality of ridges.

Preferably the board has at least four sides.

In a second aspect the invention consists in a walkway comprising at least a first walking board and a second walking board, each walking board having an upper surface upon which a user may walk in use, a lower surface which is substantially opposite the upper surface, and four sides generally bounding the upper and lower surfaces, each of the sides including one or more teeth thereon, the construction and arrangement of the teeth being such that a side of the first walking board may be placed adjacent to any side of the second walking board so that the one or more teeth on the respective sides intermesh whereby the upper surface of the first walking board and the second walking board form a substantially continuous walking surface.

In a third aspect the invention consists in a kit of parts comprising a walking board as set forth in the first aspect above having an aperture provided in a tooth of each side, and an elongate pin adapted to be received in the aperture for engaging the walking board with a further walking board.

In a fourth aspect the invention consists in a walking board having two ends and an engagement means provided at at least one end, the engagement means allowing the walking board to be pivotally engaged with an end of a further walking board.

Preferably the engagement means may include a hinge.

Preferably the engagement means may include a projection from the board, the projection including an aperture therein.

Preferably an elongate member such as a pin may be provided within the

aperture.

In a fifth aspect the invention provides a method of forming a walkway, the method comprising the steps of taking a plurality of walking boards according to any one of the preceding aspects and placing a side or end of each of the walking boards adjacent to the side or end of another walking board so as to form a walkway.

Preferably the method includes the step of engaging the walking boards so as to maintain the walking boards in an adjacent relationship.

Preferably the step of engaging the walking boards includes the step of providing a pivotal engagement.

Preferably the step of providing a pivotal engagement includes the step of engaging an elongate member through apertures in projecting portions or teeth of adjacent walking boards.

Drawing Description One or more embodiments of the invention will now be described with reference to the accompanying drawings in which Figure 1 is a perspective view from above of a walking board Figure 2 is a perspective view from below of the walking board of Figure 1 Figure 3 is a side elevation of the walking board of the preceding Figures Figure 4 is a plan view of the walking board of the preceding Figures Figure 5 is a side elevation of the walking board of the preceding Figures in cross section through line A-A of Figure 4

Figure 6 is an end elevation of the walking board of the preceding Figures Figure 7 is a plan view from below of the walking board of the preceding Figures Figure 8 is a perspective view of an engagement member for use in conjunction with the walking board of the preceding Figures Figure 9 is a partial perspective view of one end of the engagement member of Figure 6, Figure 10 is a diagrammatic plan view showing an arrangement of walking boards according to the preceding figures, Figure 11 is a plan view from below of an alternative embodiment of the invention, Figure 12 is an end elevation in cross-section through line B-B of Figure 11, and Figure 13 is a perspective view from above showing an alternative tread pattern.

Detailed Description Referring to the drawings, a walking board, also commonly referred to by those skilled in the art as a duckboard, is shown generally referenced 1. The board is generally planar having an upper surface 2 upon which users walk in use, a lower surface 3, and a number of sides, preferably four sides, referenced 4-7 in the drawings which generally bound the upper and lower surfaces. The sides are toothed, having at least one tooth projecting from each side. That is to say each side has one or more projections 10 and/or indentations 12, as shown in the drawing figures.

The upper surface 2 preferably has a friction enhancing surface to facilitate frictional contact with the soles of a user's shoes and thus reduce slippage. In the embodiments illustrated the upper surface 2 has raised ridges which may be provided in a pattern. Those skilled in the art will realise that a number of different patterns or surface configurations may be adopted.

The lower surface 3 includes a number of ribs 8. These are preferably recessed, as shown in the drawings, but could alternatively protrude from the lower surface, or could be provided internally of the board. The ribs 8 provide structural support to confer additional rigidity to the overall construction of the board (which is preferably moulded from plastics material). In a preferred embodiment, the moulding process provides a substantially rigid board which is approximately 1-2 metres long (most preferably approximately 1.5 metres long) by 0.5-1 metre wide (most preferably approximately 800 millimetres wide) and 30-70 millimetres deep (most preferably approximately 50 millimetres deep).

It is preferred that the board has a substantially hollow interior. This is achieved in practice using a rotational moulding technique. We have found that a rotationally moulded board having the preferred dimensions detailed above is sufficiently robust for its intended purpose of providing a walkway, pathway or floor area on which a person may stand or walk while also being sufficiently light to be easily handled by a user and easily transported to various locations. The board is also relatively cheap to manufacture.

The toothed sides provide a number of advantages. The first is that boards may be laid adjacent to each other as shown in Figure 10 so that a substantially continuous walking surface can be created. Not only can the boards be used to create a walkway, but they may also be laid adjacent to each other to create a substantially continuous"paved"area so that a platform may be provided if desired. The teeth (i. e. the projections and/or recesses 10 and 12) are arranged so that a side of a second walking board of the same design may be placed adjacent to any side of a first walking board so that the one or more teeth on the respective sides intermesh whereby the upper

surfaces of the walking boards form a substantially continuous walking surface. There will typically be some play between the intermeshed teeth as a result of tolerances necessary to enable ease of assembly of the boards and as a result of manufacturing tolerances, so the walking surface may not be a completely continuous surface but is substantially continuous. Thus a number of boards may be used to form a support structure such as a walkway or a platform such as a temporary floor for example. An intermeshed arrangement of a plurality of boards 1 is shown in Figure 10, the arrows 20 indicating directions in which further boards may be laid so as to create an intersecting pathway.

As will be seen, the arrangement of the teeth on sides 4-7 is such that a substantially continuous surface will be formed when boards are laid next to each other in almost any pattern.

The teeth or projections on the sides also facilitate engagement of adjacent boards. As shown in the Figures, each projection includes an aperture 22 therethrough. The apertures on each projection allow an elongate member such as elongate engagement pin 24 (shown in Figures 8 and 9) to be disposed through aligned apertures when the sides of adjacent boards are appropriately positioned relative to each other. Therefore, the pin 24 prevents the engaged boards from being separated without first removing the engagement pin. The pin 24 generally has a head 26 at one end and a securing pin 28 at the other. The engagement pin may be provided in varying lengths, e. g. a longer pin to engage boards along their long sides, and a shorter pin such as that shown in Figure 8 which is adapted to engage boards along the shorter sides.

As shown in Figure 9, the end of engagement pin 24 has an aperture 30 and securing pin 28 (which will typically comprise a known form of engagement pin or clip such as a hitch pin) can be disposed through aperture 30 to frictionally or resiliently engage with the pin 24 so that it remains disposed through the apertures 22 in use. Rather then requiring a head at one end, the engagement pin 24 may have an aperture 30 at either end so that the engagement pin 24 is retained by having hitch pins 28 at both ends.

The pin 24 may also be dimensioned so that it may project in use some distance from the board. In this way a fastening device such as a strap of flexible or malleable material may be disposed about the exposed projecting portion of the pin 24 and fastened to a surrounding structure (for example nailed or screwed to a part of a roof structure on which the board is provided) to secure the board thereto.

An alternative embodiment is shown in Figure 11. In Figure 11, the board illustrated is substantially the same as the board described above with reference to the preceding figures, with the exception that the ribs 8 are provided longitudinally rather than transversely across the board. Figure 12 shows the embodiment of Figure 11 in cross-section.

In Figure 13, an alternative tread pattern is shown on the upper surface of the board. This tread pattern may be used with the embodiment shown in Figures 11 and 12, or the embodiment of Figures 1 to 10.

An advantage with the use of the engagement provided by the invention is that the pin 24 provides a pivotal or hinged connection between adjacent boards. Therefore, the boards may be disposed over undulating surfaces or disposed, for example, across a ridge in the roof of a building, the hinge being located over the ridge, so that a substantially continuous walking surface or structure is still provided. Similarly, the structure may traverse a depression in a roof or similar structure.

Where in the foregoing description, reference has been made to specific components or integers of the invention having known equivalents then such equivalents are herein incorporated as if individually set forth.

Although this invention has been described by way of example and with reference to possible embodiments thereof, it is to be understood that modifications or improvements may be made thereto without departing from the scope of the invention as defined in the appended claims.

The word"comprise"and variations such as"comprises"or"comprising"is intended to be interpreted herein in an inclusive sense rather than an exclusive sense, i. e. as meaning"including but not limited to".