Van Erven, Waltherus Joseph Maria
|1.||Scaffold board (1) wherein a protector (4) is arranged on at least one of its head ends (3) , characterized in that a protector (4) of plastic is arranged on the head end (3) of a board (2) .|
|2.||Scaffold board (1) as claimed in claim 1, characterized in that the protector (4) consists of a polyurethane.|
|3.||Scaffold board (1) as claimed in claim 1 or 2, characterized in that the head end (3) is bevelled or rounded.|
|4.||Method for manufacturing a scaffold board (1) as claimed in any of the foregoing claims, characterized in that a protector (4) of plastic is moulded onto a head end (3) of a board (2) bounding a mould cavity (7) by injecting this plastic in liquid form into the mould cavity (7) .|
|5.||Device (6) for manufacturing a scaffold board (1) according to the method of claim 4, characterized by a mould cavity (7) for moulding a protector (4) of plastic onto a head end (3) of a board (2) . *****.|
1 The invention relates to a scaffold board, wherein a
* protector is arranged on each of its head ends. Such a scaffold board is known. The protector consists therein of a steel hoop which prevents the board from splitting.
5 The hoop may protrude when the scaffold board is manufactured inaccurately. It may then catch on something during work operations. This impedes a smooth progress of operations and may be a further cause of the hoop coming loose. 10 The steel hoop has rather sharp edges.
All this can cause hand injuries and/or splitting of the board.
The invention has for its object to prevent, such injuries and to make the board more sturdy. 15 For this purpose a protector of plastic is arranged on each head end of the scaffold board. Not only are hand injuries thereby reduced, because sharp edges are avoided, but in particular the lifespan of the scaffold board is also prolonged because the protector of plastic 20 adheres more firmly to the wood of the board and because penetration of moisture into the wood fibres on the head ends is prevented.
The invention also provides a method and a device for manufacturing a scaffold board according to the 25 invention.
The invention will be elucidated in the description following hereinafter with reference to a drawing. In the drawing: figures 1, 2 and 3 each show a perspective view of a
* 30 fraction of a scaffold board according to the invention; i and figure 4 shows a device for performing the method according to the invention.
The scaffold board 1 consists of a wooden board 2 35 which is for instance 20 cm wide and 34 mm thick and has
a considerable length, for instance 4 to 6 m. Formed over the whole width and the whole height of each head end 3 is a protector 4 consisting of a layer of plastic with a thickness t for instance in the order of magnitude of 1 cm. For this purpose liquid plastic is preferably moulded against this head end 3. This takes place preferably in a mould, for instance the device 6 of figure 4. The plastic penetrates into the pores of the wood and adheres extremely well to the head end wood. Each head end 3 of board 2 of figure 1 has bevelled corners. These corners could however also be rounded.
In figure 2 the head end 3 has an arcuate form. In figure 3 the protector 4 has roundings 5. Sharp corners on the board 1 are otherwise avoided as much as possible.
As plastic can be applied a polyurethane plastic, although other plastics can also be used.
According to the method of the invention plastic is injected in the device 6 on each head end 3 of the wooden board 2 by sliding the board 2 into the mould cavity until it comes to a stop against a pin 9 loaded by a pressure spring 8. Thereafter, using a side bounding member 10 by means of hydraulic cylinders 11 and a cover 12 by means of hydraulic cylinders 13, the board is enclosed in the thus closed mould cavity 7, whereafter plastic is injected from nozzle 14 into the remaining part of mould cavity 7 for moulding on of the protector 4.
After curing and/or reaction of the plastic, for instance polyurethane, the device 6 is opened and the head end 3 taken out of the mould cavity. The other head end 3 of board 2 is provided with a protector 4 in the same way.
The mould cavity 7 is of course adapted to the desired shape of the protector 4.