A method for fastening a finishing work member on a metal framework and assembly of such a member with a framework rail to which it is fastened The field of the invention relates to the fastening of finishing work members of a structure on a metal framework, particularly on a thin framework. A finishing work member should be meant as including, but not exclusively, wall or lining members, members and fittings in any material, such as plastic, of particular trades, such as for instance electrician chutes or other insulating components. Wall or lining member can mean plasterboards and cement boards and, more generally, hydraulic binder based boards. Furthermore, the problem that has given rise to the invention of the present application has precisely cropped up concerning plasterboards .

But the Applicant claims, from now on, that they waive, in the most clearly way, to claim any right on their invention linked to such hydraulic binder based plates or boards. This waiving is dictated by purely industrial and tactical reasons, which do not need to be presented here.

The original problem was thus the fastening of plasterboards to a metal framework. A plasterboard is a board comprising plaster between two cardboard sheets. Until recently, they were fastened to C-shaped metal rails by means of screws. But screwing is of relatively long implementation and a faster method has been looked for. Nailing plates on rails has thus been contemplated. Nailing nails on C-shaped rails has thus shown that it was neither appropriated, since the nail driving resulted in the flexion of the C-arm receiving the nail (a so-called oblique flexion) so partly disengaging the rail plate and thus creating an adverse clearance. And that is how the invention of the present application has thus been proposed.

The invention relates thus and first of all to a method for fastening a finishing work member of a structure, except for any hydraulic binder based board, to a metal framework, wherein it is taken as a framework a rail shaped to resist an oblique flexion, the member is laid down against the rail and the member is nailed to the rail.

Preferably, a Z-shaped rail is considered, the oblique part of which binds both parallel wings for making the means limiting the oblique flexion.

Advantageously, before laying down the finishing member against the rail, a glue layer is interposed, by coating of at least one of the three means of the group comprising each nail head, the finishing work member and a rail wing.

Since the oblique flexion is limited, that is that the clearance created by nailing between the finishing work member and the rail remains low, very little glue is sufficient to perfect the fastening. If, according to the method of fastening of the prior art, with a C-shaped rail, one had wanted to fill the clearance with glue, a too important quantity would have been necessary. The general implementation of a Z-shaped rail, some glue and nails thus offers an undeniable advantage .

The invention also relates to the assembly, with no hydraulic binder based board, of at least one finishing work member of a structure and at least one framework rail on which is fastened the finishing work member, characterized in that this finishing work member is fastened to the rail by nails and the rail presents a profile with two wings interconnected by an oblique linking bar for limiting the oblique flexion.

Advantageously, a glue layer is interposed between the rail and the finishing work member.

Preferably, the oblique part of the rail profile, linking both wings on one of which is nailed the finishing work member, comprises means arranged to cooperate with the fastening nail tips and thus hang the nails.

Finally, in the most elaborated embodiment of the invention, the fastening quality, that is the mechanical peel strength, is ensured by the combination of the performance in four complementary areas :

- the joining area for the finishing work member, a nail and the (wing) rail,

- the joining area for a nail and the (oblique part) rail,

- the joining area for the nail head and the finishing work member, and

- the joining area for the nail stem and the finishing work member.

The Z-shaped profile is characterized by two parallel wings connected by an oblique bar. Very similar to such a profile is the S-shaped profile, only reversed and with curvilinear (curved) and not rectilinear (planar) wings and bar. The invention thus also applies to a S-shaped profile.

The invention will be better understood with the aid of the following description of the method and of the whole invention, referring to the attached drawing, wherein:

Fig. 1 is a schematic illustration of a preferred embodiment of the method of the invention, and

Fig. 2 is a partially sectional schematic view of the whole invention.

Referring to Fig. 1, the method that will be described aims at fastening on a metal framework 1, here a rail with a S-shaped profile, a finishing work member 2 of a structure, here an electrician chute. The metal profile 1 comprises two parallel wings 3, 4 connected by an oblique bar 5. In this example, the wings and the bar are planar. The fastening is performed by nailing a nail 6 comprising a stem 7 and a head 8. The chute is laid down against one 3 of the parallel wings of the rail and the stem 7 of the nail 6 is pressed perpendicularly to the wings 3, 4 of the profile, till the head 8 abuts against the chute 2 and here, after the stem 7 has run through the linking oblique bar 5. Upon nailing, the oblique bar 5 has limited the oblique flexion of the rail wing 3.

Referring to Fig. 2, being more precise than Fig. 1, showing substantially the same assembly, but in a perpendicular plane and on which the same means that those of Fig. 1 are designated by the same reference numbers, the nail 6 stem 7, upon nailing, has slightly altered all around (9) the structure of the chute 2. That is why, in advance, we have preferred to interpose one glue layer 10 between the chute 2 and the rail 1 and another glue layer 11 between the nail head 8 and the chute 2. To this end, before nailing, outer and opposed surfaces 12, 13 of the chute 2 have been coated both with a layer of fastening glue. We could have also coat the adjacent profile wing 3 and the underside of the nail head 8. We could also have coated only one of both outer surfaces 12, 13.

Due to the slight alteration of the member 2 by the nail, part of the glue that have been coated has flowed (14) along the nail stem 7, participating incidentally in the improvement of the fastening by creating a glue bridge between the profile 1 and the nail head 8. After nailing, as illustrated in Fig. 2, the glue layers 10, 11 are crushed. Obviously, the member 2 is fastened to the rail 1 by a plurality of nails 6, so that a glue primer 14 extends between the rail 1 and each nail head 8.

Fastening glue should be understood as any glue used by a man skilled in the art in the fastening and anchoring field and that generally comprise a resin, often a polymer one, and a hardener.

Finally, in the assembly that has just been described, whether the assembly is with glue or without glue, four important interaction areas are to be noticed:

the area between the surface 12 of the free member of the rail 1, on one hand, and the nail head 8, on the other hand,

the area of the nail stem portion 7 extending in the member 2,

the cooperation area between the nail stem 7, the member 2, by its surface 13, and the rail 1, 3,

the cooperation area between the nail stem 7 and the linking oblique bar 5 of the rail. It is by combining the performance of these four complementary areas that the quality of the fastening (mechanical peel strength) is assumed.

In the embodiment of Fig. 1, a central portion 15 of the linking bar 5 shows asperities 16 for cooperating with the tip 17 of the nail stems to better hook them.