WO1996023116A1

WO1996023116A1 - Scaffolding platform

Info

Publication number: WO1996023116A1
Application number: PCT/FR1996/000119
Authority: WO
Inventors: André Peronnier; Gérard JULLIEN
Original assignee: Sgb Comabi
Priority date: 1995-01-25
Filing date: 1996-01-24
Publication date: 1996-08-01
Also published as: ES2127617T3; EP0805904B1; FR2729692A1; DE69601155D1; DE69601155T2; EP0805904A1; AU4626396A; ATE174651T1; AU706743B2; FR2729692B1; CA2210952A1

Abstract

An aluminium/wood scaffolding platform consisting of an aluminium framework (1) and a plywood floor (2) fitted into the framework (1). The framework itself consists of two side members (3) and two end cross members (4) in the form of extruded aluminium profile members. The side profile members (3) with a preferably triangular cross-section comprise a longitudinal groove (11) for receiving a steel reinforcing rod (16) which is also used to attach the cross members (4) engaging the ends of the side members (3), as well as to attach hooks (5). In addition, a corner piece (20) is provided at each joint between a cross member (14) and a side member (3).

Description

SCAFFOLDING PLATFORM The present invention relates to a scaffolding platform, more particularly but not exclusively to a scaffolding platform of the aluminum / wood type.

In the field of scaffolding, two main types of trays are known, constituting work surfaces for personnel, namely: steel trays, and aluminum / wood trays. The steel plates generally consist of a perforated sheet to be less slippery, and folded or formed by roller burnishing in order to obtain a rigid floor, carrying at its ends positioning hooks for the plate on the tubular structure of the scaffolding . This first type of tray is not concerned with the invention.

The aluminum / wood trays, in which the present invention is concerned, generally consist of a rectangular aluminum frame, and a plywood floor, fitting into the aluminum frame. The frame usually consists of two supporting beams, which may have a length of 3 m, 2.5 m or 2 m, and two end crosspieces. The side rails and cross members are commonly formed by extruded hollow aluminum profiles. The profiles which constitute the side members have longitudinal grooves, in which are placed the longitudinal edges of the plywood floor, which itself has very good mechanical strength. The end crosspieces carry hooks used to position the plate on the tubular steel structure of the scaffolding, the hooks generally being welded or bolted.

To assemble the side members and the end cross members of the aluminum frame, a known solution consists in welding each end cross member against the side members, generally at 90 °. The welds connect the two vertical sides of the cross member to a side wall of the side members. The assembly by welding of aluminum profiles, by a TIG or MIG type process, is a long and expensive operation, difficult to robotize, one of the effects of which is to reduce the mechanical resistance of aluminum by around 50%. in the weld area. In addition, welded, metallurgically transformed areas are sources of cracks. Another kind of aluminum / wood tray has a ladder beam made up of crimped rails and bars, supporting the plywood floor. The hooks are generally arranged in the extension of the side members. In this case, the crimping of the bars on the beams requires qualities of aluminum with a very high percentage of elongation, therefore with low mechanical strength, which must be compensated for by a multiplication of the number of bars. The fact of not having end crosspieces, in this kind of scaffolding plate, prohibits certain provisions of the hooks.

In all the cases described above, the section of the aluminum beams is studied in such a way that it ensures the resistance to bending of the plate. It is therefore necessary that this section is sufficiently high, and that the walls of the profile are thick, to obtain an inertia leading to the desired mechanical strength. This eventually results in two drawbacks: On the one hand, the weight of the aluminum beams is important, and therefore their cost is high.

On the other hand, given the large height of the section of the profiles forming the side members, the storage height of scaffolding plates placed on top of each other is large, and therefore the transport cost is increased, since in a given volume the number of trays is lower.

Furthermore, all these plates are not designed to support plinths, arranged above a longitudinal edge of a plate. The plinths therefore most often remain attached to the tubular steel structure of the scaffolding, more particularly to the posts. In some cases, however, inserts are welded to the side members or the end crosspieces to support these baseboards. Such arrangements obviously remain expensive, and increase the overall width of the plates. When several trays are juxtaposed to form a continuous work surface, play due to the presence of the support pieces for the plinths inevitably appears between two adjacent trays.

In summary, the problems posed by the current scaffolding plates of the aluminum / wood type are: the connection of the end crosspieces with the beams, the height of the beams in relation to their section and therefore the weight of these elements, their cost and their storage volume, fixing the plinth, and the overall cost of the tray resulting from both the amount of aluminum required and the assembly time. The invention aims to solve these various problems, and thus eliminate the drawbacks set out above, by providing a scaffolding plate of the aluminum / wood type which is light and of economical manufacture, while offering high mechanical strength and low storage footprint.

To this end, the present invention essentially relates to a scaffolding plate, in particular of the aluminum / wood type, consisting of a rectangular frame in particular of aluminum and a floor in particular of plywood, fitting into the frame, this frame itself consisting of two beams and two end crosspieces in the form of extruded profiles, in particular of aluminum, the plate being remarkable in that the frame rails have at least one longitudinal groove or a longitudinal duct receiving a reinforcing means of the steel rod type and / or means for fixing the end crossmembers, applied against the ends of the side members.

According to a preferred embodiment of the invention, the profiles constituting the side members of the frame of the scaffolding plate have a substantially triangular cross section, the tip of the triangular section being directed downwards, these profiles comprising a longitudinal groove or a longitudinal duct situated in the region of the lower point of its triangular section, and capable of receiving the reinforcing means of the steel rod type, while the base of said triangular section, opposite its point, partially forms the surface of the floor of the scaffolding platform. The beams thus have an optimal section, the choice of a triangular section with point downwards, combined with a steel rod, making it possible in particular to reduce the aluminum mass of the beam. Indeed, each spar behaves in flexion in the manner of a beam, the upper part of its section working in compression and the lower part of its section working in traction. Insofar as the forces or stresses must remain below fixed limits (approximately 13 kg / mm ² ) for aluminum, a certain amount of aluminum is in principle necessary. The proposed configuration, with triangular section, makes it possible to reduce as much as possible the quantity of aluminum working in traction, by replacing it by a continuous steel rod which can easily work with stresses of 36 kg / mm ² or more in traction. By thus transferring the forces to a steel rod, which can accept them, a reduction in the height of the section of the aluminum profile constituting the spar is also obtained, and consequently a reduction in the storage volume of the scaffolding plates.

Another advantage of the arrangement proposed here is to facilitate the assembly of the aluminum frame of the scaffolding plate. In this regard, according to a first advantageous possibility, the continuous steel rod received in the longitudinal groove or the longitudinal duct of the profile constituting the spar has threaded ends, intended to pass right through the end crosspieces, applied against the ends of the side members, and to receive tightening nuts. Thus, by simply associating two steel rods respectively with the two beams, there are means for assembling the crosspieces with the beams to constitute the frame of the scaffolding plate, the rods thus ensuring the blocking of the frame of the scaffolding plate, while strengthening the profiles forming the side members. The advantage of this arrangement, which makes the steel rods play a double role, is to eliminate the weld connections and their drawbacks, as well as any added assembly parts. In addition, in the case where the plate hooks are located in the extension of the side members, the steel rods carrying nuts at their threaded ends can also ensure the fixing of the hooks, which gives them a third function. This latter arrangement is therefore particularly advantageous: two rods fitted with nuts, associated respectively with the two beams, make it possible to carry out the complete assembly of the scaffolding plate, including its hooks, with an extremely simple overall structure: the beams are formed by cutting aluminum profiles, desired length, without any other operation, while the sleepers only require drilling holes for the passage of the ends of the steel rods. From the point of view of industrial production, a very simple tool (tightening wrenches) is enough to completely assemble the scaffolding plate. Of course, a tightening force of suitable value must be predetermined, and be checked during assembly. Overall, production costs are thus greatly reduced, compared with traditional manufacturing.

Alternatively, in certain cases where the strength of the plate and the side members does not require the establishment of a continuous steel rod extending from one end cross member to the other, the longitudinal groove or the longitudinal duct of each spar can always be used for the assembly of the end crosspieces, by providing that this groove or this duct receives, at its open ends at the ends of the spar, fixing pins of a common type, which receive themselves fixing screws passing right through the end crosspieces, applied against the ends of the side members.

If the steel rods or other fixing means are housed in grooves, open towards the outside, the arrangement also allows an easy visual examination of the state of these rods or other fixing means.

In all cases, mechanical connections are thus made between the side members and the end cross members, by screw means, which make it possible, if necessary, to assemble components made from separate materials, for example by combining side members in aluminum with steel crosspieces, the hooks being made of aluminum, or alternatively by combining beams made of composite materials with aluminum crosspieces. According to an advantageous arrangement, the length of the end crossmembers is determined in such a way that the end faces of each crossmember, assembled to the longitudinal members, correspond substantially to the vertical median of the section of these longitudinal members, and more particularly to the median of the triangular section (as defined above) of said beams. As a result, at each junction of a cross member and a spar, not only is the end of the cross member cleared, but also a fraction of the end of the spar is released, thus allowing the insertion of 'a corner piece.

Thus, according to another aspect of the present invention, it relates to a scaffolding plate, in particular of the aluminum / wood type, consisting of a rectangular frame in particular of aluminum and a floor in particular of plywood, inserting into the frame, this frame itself being made up of two longitudinal members and two end crosspieces in the form of extruded profiles, in particular aluminum, the plate being remarkable in that at each junction of a crosspiece and a spar is inserted a corner piece, engaged on the one hand in the cross member and on the other hand in the spar, the corner piece being automatically blocked when the cross member is fixed to the spar. This corner piece, thus blocked on the frame of the scaffolding plate without any other fixing accessory, can alone perform several functions, thanks to an appropriate shape:

First of all, the corner piece closes the angle of the two sections respectively constituting the beam and the cross member, thus preventing the penetration of water or other products inside the sections.

In addition, the corner piece advantageously comprises, opening onto its upper face, a housing in particular of cylindrical shape, suitable for fixing the end of a plinth along the plate. scaffolding. The plinth can thus be fixed directly on the plate, whereas currently the plinths are generally fixed between the posts of the scaffolding, which leaves a significant space between the plinth and the plate, from where a risk of falling. objects such as tools, a drawback which the invention remedies.

Furthermore, this corner piece ensures, in addition to the screwed assembly of the cross member on the spar, mechanical locking between this cross member and said spar, preventing any torsional movement.

Finally, by providing for the corner piece a rounded external shape, this corner piece eliminates by its presence the cutting edges located in the region of the angle of the plate, which result from the cutting of the sections constituting the spar and the end crosspiece. The plate is thus made less angular, therefore less dangerous. In addition, the protruding corner piece provides impact protection for the aluminum frame made up of side members and cross members.

In any case, the invention will be better understood with the aid of the description which follows, with reference to the appended schematic drawing representing, by way of examples, some embodiments of this scaffolding platform:

Figure 1 is an overall perspective view of a scaffold plate of the aluminum / wood type, according to the present invention;

Figure 2 is an exploded perspective view of the corner region of this scaffolding plate, in a first embodiment;

Figure 3 is a longitudinal sectional view passing through the region of this angle, the plate being assembled; Figure 4 is a cross-sectional view along line IV-IV of Figure 3; Figure 5 is a partial view, in plan from above, of a variant of this scaffolding plate;

Figure 6 shows a variant of the section of the profile constituting one of the side members of such a plate; Figure 7 is a perspective view, similar to Figure 2, illustrating another embodiment of this scaffolding plate;

Figure 8 is another perspective view of the region of an angle of a scaffolding plate according to the invention, more particularly illustrating the fixing of the plinth;

Figure 9 is an exploded perspective view, corresponding to part of Figure 8.

As shown in Figure 1, the invention relates to a scaffolding plate which comprises a rectangular support frame 1, of elongated shape, and a floor 2. The support frame 1 consists of two beams 3, constituted by extruded aluminum profiles, and two end crosspieces 4, formed by other extruded aluminum profiles. The scaffolding plate also has, at each of its ends, a pair of hooks 5 provided for its positioning on the tubular steel structure (not shown) of the scaffolding. In the example considered, this scaffolding plate is again provided with a plinth 6, extending along one of its long sides.

Referring to Figures 2 to 4, each aluminum profile, constituting a beam 3 of the frame 1, has a substantially triangular, but asymmetrical cross section, the tip of which is turned downwards. This profile, of generally tubular conformation, thus comprises a substantially horizontal upper face 7 (corresponding to the base of the triangular section), an external inclined flank 8 (corresponding to one side of the triangular section), and an internal inclined flank 9 ( corresponding to another side of the triangular section). At its upper part, on the side facing inwards, the profile of the spar 3 forms a longitudinal groove 10, into which is inserted a longitudinal edge of the floor 2, made of plywood, the upper face 7 of the profile thus extending the surface of the floor 2.

In its lower part (corresponding to the tip of the triangular section), the profile of the spar 3 forms a longitudinal groove 11, of substantially circular section, open downwards.

The tubular conformation of the profile constituting the spar 3 defines an interior space 12. Two interior longitudinal ribs 13 and 14, attached respectively to the upper part and to the lower part of the profile and located directly above each other, protrude into the interior space 12.

Each aluminum profile, constituting an end cross member 4 of the frame 1, has a substantially rectangular cross section, its configuration also being tubular. At the two ends of this cross-section 4, in the vertical walls of the latter, are provided holes 15 located in correspondence.

The longitudinal groove 11 of each spar 3 receives a continuous steel rod 16, extending over the entire length of the spar 3 and serving as reinforcement means as well as means for fixing the end crosspieces 4. For this purpose, the two ends of each steel rod 16 have a thread 17. These threaded ends of the rod 16, protruding from the corresponding ends of the beam 3, pass through the holes 15 of the crosspieces 4 applied (in the assembled state - see FIG. 3) against the ends of the side members 3. A nut 18, screwed from the outside onto the thread 17 of each end of the rod 16, secures the cross member 4 against the corresponding end of a side member 3. In the embodiment shown in Figures 2 to 4, the hooks 5 are located in the extension of the side members 3. These hooks 5 have a base pierced with a hole 19, and threaded onto the threaded end of the steel rod 16 , in front of the cross member 3. Thus, the tightening of the nut 18 ensures the simultaneous fixing of the cross member 4 and the hook 5.

On the contrary, FIGS. 1 and 5 illustrate a variant in which the hooks 5 have, with respect to the side members 3, a position offset towards the inside. In this case, the steel rods 16 and the nuts 18 only ensure the assembly of the side members 3 and the cross members 4. The hooks 5 are here fixed separately on the corresponding end cross members 3, in particular by means of bolts (here not represented).

At each angle of the plate, the end crosspiece 4 is interrupted along a vertical plane which corresponds, substantially, to the median of the triangular section of the spar 3. The interior space 12 of the profile constituting this spar 3 is thus made accessible , and allows the introduction of a corner piece 20, of synthetic material or other material, clearly visible in FIG. 2. The corner piece 20 comprises a body 21, and two tenons 22 and 23 arranged at right angles . The first tenon 22 is engaged in a housing 24 at one end of the cross-member 4. The second tenon 23 is engaged in the interior space 12 of the profile constituting the beam 3, and more particularly in the part of this interior space 12 delimited by the outer inclined flank 8 and by the two superimposed ribs 13 and 14. The corner piece 20 is first engaged in the housing 24 of the cross member 4, then introduced into the interior space 12 of the spar 3, and it automatically finds itself blocked when the nut 18 is tightened on the thread 17 of the rod 16. The body 21 of the corner piece 20 has a rounded outer face. The upper face of the body 21 has a housing 25, here of cylindrical shape, designed to receive a retaining rod 26 fixed to the end of the plinth 6 - see also FIG. 1.

By its presence, the corner piece 20 provides mechanical locking between the cross member 4 and the spar 3. In fact, it can be assumed that the forces exerted on the plywood floor 2, inserted in the longitudinal groove 10 of the profile of the spar 3, would tend to tilt this profile inward, relative to a pivot axis formed by the steel rod 16. However, the corner piece 20 whose second stud 23 has a profile adapted to that of the spar 3 prevents this tilting and ensures blocking of the assembly.

In a variant, shown in FIG. 6, the aluminum profile constituting the beam 3 always has a triangular section, with the tip facing downwards, but this profile has two longitudinal grooves. As before, a longitudinal groove 11 of circular section is provided in the lower part of the profile (tip of the triangular section). Another longitudinal groove 27 is formed in the upper part of the profile of the beam 3, under its upper face 7. By placing in these two grooves 11 and 27 steel rods, or other means (as described below) used for fixing the end crosspieces 4, here avoids the undesirable tilting of the beam 3. As illustrated in FIG. 7, the means for fixing the end crosspieces 4 can also consist of at least one pin 28, introduced at the end of the beam 3 in the groove 11, which here does not receive any continuous steel rod. As before, the cross-member 4 has holes 15 at its ends located in correspondence. A fixing screw 29, introduced from the outside, passes through the holes 15 and is screwed into the dowel 28. Of course, in the case of a spar profile 3 having two superimposed grooves 11 and 27 (Figure 6), the fixing of the crosspiece 4 on the beam 3 can be produced by means of two dowels 28 and two screws 29.

FIGS. 8 and 9, which represent the region of an angle of the scaffolding plate, show more precisely an embodiment of the corner piece 20, with its body 21, its two tenons 22 and 23, and its housing 25 which receives the retaining rod 26 fixed to the end of the plinth 6. FIG. 8 clearly shows how the corner piece 20, put in place, closes the angle of the two sections constituting respectively the spar 3 and the cross member 4. FIG. 9 shows the detail of the means for fixing one of the hooks 5, when these are offset with respect to the side members 3, these fixing means comprising a bolt 30 engaged through holes 31 in the cross member 4. As is obvious, and as is clear from the above, the invention is not limited to the sole embodiments of this scaffolding plate which have been described above, by way of examples; on the contrary, it embraces all the variants respecting the same principle. Thus, in particular, that one would not depart from the framework of the present invention by a modification of the section of the profiles constituting the longitudinal members, the triangular section being replaceable by a trapezoidal section, or even by a rectangular section , as long as these sections retain at least one longitudinal groove or a longitudinal duct or channel receiving a continuous steel rod or fixing pins of the end crosspieces. In the same vein, material changes can be envisaged for certain components, without departing from the main inventive idea. Finally, it will be noted that the characteristics relating to the corner pieces, in particular the use of these corner pieces for fixing the plinths, are applicable independently of the use of the reinforcing rods housed in the side members.

Claims

CLAIMS 1. Scaffolding tray, in particular of the aluminum / wood type, consisting of a rectangular frame (1) in particular of aluminum and a floor (2) in particular of plywood, fitting into the frame (1), this frame (1) itself consisting of two beams (3) and two end crossmembers (4) in the form of extruded profiles, in particular aluminum, characterized in that the profiles constituting the beams (3) of the frame (1 ) comprise at least one longitudinal groove (11,27) or a longitudinal duct receiving a steel rod-type reinforcing means (16) and / or fixing means (28) of the end crosspieces (4), applied against the ends of the side members (3).

2. Scaffolding plate according to claim 1, characterized in that the sections constituting the side members (3) of the frame (1) have a substantially triangular cross section, the tip of the triangular section being directed downwards, these sections comprising a longitudinal groove (11) or a longitudinal duct situated in the region of the lower point of its triangular section, and capable of receiving the steel rod-type reinforcing means (16), while the base (7) of said section triangular, opposite its point, partially forms the surface of the floor (2) of the scaffolding platform.

3. Scaffolding plate according to claim 1 or 2, characterized in that the longitudinal groove (11) or the longitudinal duct of each profile constituting a spar (3) receives a continuous steel rod (16) which has threaded ends (17), provided for passing right through the end crosspieces (4), applied against the ends of the side members (3), and for receiving tightening nuts (18).

4. Scaffolding plate according to claim 3, comprising hooks (5) located in the extension side members (3), characterized in that the steel rods (16), carrying nuts (18) at their threaded ends (17), also secure the hooks (5).

5. Scaffolding plate according to claim 1 or 2, characterized in that the longitudinal groove (11) or the longitudinal duct of each profile constituting a spar (3) receives, at its open ends at the ends of the spar (3), fixing pins (28), which themselves receive fixing screws (29) passing right through the end crosspieces (4), applied against the ends of the side members (3).

6. Scaffolding plate according to any one of claims 1 to 5, characterized in that the length of the end crosspieces (4) is determined so that the end faces of each crosspiece (4), assembled to the longitudinal members (3), correspond substantially to the vertical median of the section of these longitudinal members (3), and more particularly to the median of the triangular section of said longitudinal members (3).

7. Scaffolding platform, in particular of the aluminum / wood type, consisting of a rectangular frame (1) in particular of aluminum and a floor (2) in particular of plywood, fitting into the frame (1), this frame (1) itself consisting of two side members (3) and two end crosspieces (4) in the form of extruded profiles, in particular aluminum, characterized in that at each junction of a crosspiece (4) and d 'a side member (3) is inserted a corner piece (20), engaged on the one hand in the cross member (4) and on the other hand in the side member (3), the corner piece (20) closing off the 'angle of the two sections respectively constituting the beam (3) and the cross

(4).

8. Scaffolding plate according to claim 7, characterized in that the profile constituting each spar (3) comprises two internal longitudinal ribs (13,14), delimiting part of the space interior (12) of this profile in which is engaged a lug (23) of the corner piece (20).

9. Scaffolding plate according to claim 7 or 8, characterized in that the corner piece (20) comprises, opening on its upper face, a housing (25) in particular of cylindrical shape, suitable for fixing the end (26) of a plinth (6) along this scaffolding plate.

10. Scaffolding plate according to any one of claims 7 to 9, characterized in that the corner piece (20) has a rounded external shape.