The present invention relates to a scaffold board.
The use of scaffolding during construction, demolition, renovation, maintenance and other building tasks is well known and wide spread. Scaffolding typically involves the temporary construction of a rectilinear framework of vertical standards, horizontal ledgers and horizontal transoms. The standards, ledgers and transoms are typically steel tubes which are interconnected by clamps. Scaffold boards are laid across the transoms in order to provide elevated working platforms. Scaffold boards are usually manufactured from solid wood or laminated veneer lumber (LVL).
There are several disadvantages associated with solid wood and LVL scaffold boards, including that: they are relatively expensive; they are relatively heavy; they are perishable; they are not UV Light resistant; they are flammable; they are not resistant to chemical contamination; they are not resistant to propagation of mould spores and bacteria; and they are not recyclable.
United States Patent Publication No. US 2013/0192927 (application Ser. No. 13/754,212) discloses an alternative scaffold board manufactured from poly vinyl chloride (PVC). The disclosed board overcomes some of the above mentioned disadvantages (e.g. they are non-perishable, UV light resistant and recyclable). However, they have the significant disadvantage of high deflection under load. As such they do not meet a variety of international and Australian Standards, particularly the deflection test for scaffold boards, which (in Australia and New Zealand) requires deflection of less than 10 mm over a 1 m span responsive to a working load limit (e.g. 210 kg) applied centrally. As a result, this product cannot be used in Australia, nor the USA, UK or Canada (which have similar standards) and many other significant building markets.
Another known alternative scaffold board has been manufactured from fibre reinforced plastic (FRP). It also overcomes several similar disadvantages of wood/LVL boards. However, it is also a relatively heavy product, is produced from a highly flammable type of plastic material, is exceptionally difficult to recycle and has exceptionally high deflection at moderately high temperatures. As a result, this product is suitable for only very specific applications.
A further known alternative scaffold board has been manufactured from polypropylene. It also does also not pass Australian standards. The board is black and becomes significantly more flexible in sunlight. It is also able to ignite and transfer a flame.
Scaffold boards have also been produced from aluminium, which suffer from similar disadvantages in terms of relatively high material and production cost and relatively high weight.
It is an object of the present invention to substantially overcome, or at least ameliorate, one or more of the above disadvantages.
Accordingly, in a first aspect, the present invention provides a scaffold board of extruded thermoplastic material, the board including:
a substantially rectangular outer profile defined by a top wall, a bottom wall and a pair of side walls; and
a plurality of strengtheners, each extending between an inner surface of the top wall and an inner surface of the bottom wall,
wherein each of the strengtheners have:
The top wall, the bottom wall, the side walls and the strengtheners preferably extend longitudinally along a length of the scaffold board.
The top wall, the bottom wall, the side walls and the strengtheners are preferably integrally formed.
The pair of top parts of each strengthener preferably defines a triangular longitudinal recess with the adjacent inner surface of the top wall. The pair of bottom parts of each strengthener preferably defines a triangular longitudinal recess with the adjacent inner surface of the bottom wall.
In one form, a hexagonal longitudinal recess is preferably defined between adjacent said strengtheners. In another form, an octagonal longitudinal recess is preferably defined between adjacent said strengtheners.
The top wall, the bottom wall and the side walls are preferably thicker than the middle parts, the top parts and the bottom parts.
The top wall and the bottom wall preferably include textured non-slip outer surfaces
The board is preferably extruded from PCV, most preferably type k62 or k66.
In a second aspect, the present invention provides a scaffold board of extruded thermoplastic material, the board including:
a substantially rectangular outer profile defined by a top wall, a bottom wall and a pair of side walls;
a plurality of top triangular hollow recesses extending longitudinally through the board, each having one side parallel to the plane of the top wall;
a plurality of bottom hollow triangular recesses extending longitudinally through the board, each having one side parallel to the plane of the bottom wall; and
a plurality of hollow hexagonal or octagonal recesses extending longitudinally through the board, each being positioned between adjacent opposed pairs of top triangular recesses and bottom triangular recesses.
In one form, the plurality of hollow recesses extending longitudinally through the board between adjacent opposed pairs of top triangular recesses and bottom triangular recesses are hexagonal. In another form, the plurality of hollow recesses extending longitudinally through the board between adjacent opposed pairs of top triangular recesses and bottom triangular recesses are octagonal.
The top wall, the bottom wall, the side walls are preferably integrally formed with the top triangular recesses, the bottom triangular recesses and the hexagonal/octagonal recesses.
The top wall and the bottom wall preferably include textured or non-slip outer surfaces
The board is preferably extruded from PCV, most preferably type k62 or k66.
In a third aspect, the present invention provides a scaffold board of extruded thermoplastic material, the board including:
a substantially rectangular outer profile defined by a top wall, a bottom wall and a pair of side walls; and
an internal honeycomb strengthening structure, within the top wall, the bottom wall and the pair of side walls, defined by a row of longitudinally extending cells, each of the cells defined by a 6 or 8 sided polygon with its longest dimension oriented normally to the plane of the top wall and the bottom wall.
In one form, the polygon is a hexagon. In another form, the polygon is an octagon.
The top wall, the bottom wall, the side walls and the strengtheners preferably extend longitudinally along a length of the scaffold board.
The top wall, the bottom wall, the side walls and the honeycomb strengthening structure are preferably integrally formed.
The top wall, the bottom wall and the side walls are preferably thicker than the walls of the honeycomb strengthening structure.
The top wall and the bottom wall preferably include textured non-slip outer surfaces
The board is preferably extruded from PCV, most preferably type k62 or k66.
Preferred embodiments of the invention will now be described, by way of examples only, with reference to the accompanying drawings in which:
As will be understood by persons skilled in the art, the above components can be increased or reduced to tailor the formula to suit particular applications, climates and temperature ranges.
The board 10 is produced in dimensions matching those of existing wood boards in order to suit existing scaffolding equipment. The board 10 is 230 mm wide, 39 mm thick (including the hot rolled grip discussed below) and produced in 2400 mm and 3600 mm lengths.
As best shown in
The strengtheners 20 each have a pair of top parts 20a and 20b, a middle part 20c and a pair of bottom parts 20d and 20e, which are all about 3 mm thick. The top parts 20a and 20b each extend the outwardly from the top of the middle part 20c to the inner surface of the top wall 12 in substantially equal and opposite directions respectively. The bottom parts 20d and 20e each extend outwardly from the bottom of the middle part 20c to the inner surface of the bottom wall 14 in substantially equal and opposite directions respectively. The pairs of top parts 20a and 20b each define a triangular longitudinal recess 22 with the adjacent inner surface of the top wall 12. Similarly, the pairs of bottom parts 20d and 20e each define a triangular longitudinal recess 24 with the adjacent inner surface of the bottom wall 14. Hexagonal longitudinal recesses 26 are defined between adjacent strengtheners.
As the board 10 is extruded, the top wall 12, the bottom 14, the side walls 16 and 18 and the strengtheners 20 all extend longitudinally along the entire length of the board 10. The top wall 12, the bottom wall 14, the side walls 16 and 18, and the strengtheners 20 are also integrally formed.
As best shown in
Another way to describe the internal strengtheners 20 is that they together form an internal honeycomb strengthening structure defined by a row of longitudinally extending cells 30. Each of the cells 30 is defined by a hexagon with its longest dimension orientated normally to the plane of the top and bottom walls 12 and 14.
The construction of the boards 10/10′, particularly the strengtheners and honeycomb cells, provides them with superior flexural rigidity and the ability to meet the Australian Standards deflection test previously mentioned. The boards 10/10′ are also lighter than the known boards previously discussed with the 2400 mm and 3600 mm length boards weighing 10.8 kg and 16.2 kg respectively. This weight reduction provides several advantages. Firstly, it reduces the material required to produce the board, which saves production and manufacturing cost. Transport and manual handling costs are also reduced. Secondly, the board 10 is light enough to be able to be passed by hand between levels during erection or dismantling of a scaffold structure, as opposed to being carried between scaffold levels up stairs and/or ladders, which greatly reduces the time of both of those tasks.
The boards 10/10′ also maintains the other advantages associated with thermo plastic construction over wooden/LVL boards including being: non-perishable; highly resistant to UV; self-extinguishing for flame; highly impact resistant; highly corrosion resistant; not allowing for transfer of radioactive particles; not contaminable by range of chemicals including asbestos; not allowing propagation of mould spores and bacteria; not allowing for infestation by insects; recyclable and environmental sustainable; and being colourable so as to be easily distinguishable for different uses.
Although the invention has been described with reference to preferred embodiments, it will be appreciated that the invention can be embodied in many other forms.
Number | Date | Country | Kind |
---|---|---|---|
2016900953 | Mar 2016 | AU | national |
2016903152 | Aug 2016 | AU | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/AU2017/000053 | 2/23/2017 | WO | 00 |