EP3434841B1 - Prefabricated staircase including a quarter turn with adjustable tread - Google Patents

Description

FIELD OF THE INVENTION

The invention relates to a staircase of the type comprising a quarter-turn, that is to say ensuring a rotation of the staircase. This staircase has an adjustable step and step height.

Furthermore, this staircase can be associated with a straight type staircase of similar structure and which does not require for its installation heavy handling means, such as conventionally implemented with traditional prefabricated stairs.

PRIOR STATE OF THE ART

Prefabricated stairs are widely used today. They are mostly made of concrete. More particularly when such staircases comprise a quarter-turn, the entire section constituting this quarter-turn is traditionally in one piece, generating significant weight, therefore requiring suitable handling tools, and furthermore limiting the possibilities of adjusting the lap of on the one hand and the height of the steps on the other, except to multiply the molds making it possible to produce such rotating quarters.

When, in addition, such quarter turns are associated with straight sections, the connection between the upper or lower end of the quarter turn and said straight section creates difficulties, in particular with regard to the need to ensure overall cohesion and mechanical resistance of the resulting staircase.

The document DE 20 2014 004 447 U1 describes a prefabricated staircase comprising a quarter-turn comprising a stringer on which unitary walking plates are fixed, the stringer consisting of a metal beam produced by cutting and bending at least one sheet metal made of steel, so as to define at least four areas for receiving the walking platforms, capable of ensuring the quarter-turn, said reception areas comprising a first support area for said walking platforms; at least four of the walking platforms being adapted to said four stringer zones to ensure the quarter turn. It does not allow adjustment of the tread or the height of the steps.

The object of the present invention is to overcome these various drawbacks, on the one hand by promoting the production and installation of such staircases, and on the other hand by allowing in a simple way to propose a possible adjustment both of the lap only the height of the steps.

STATEMENT OF THE INVENTION

The invention proposes a prefabricated staircase comprising a stringer, no longer made of concrete but of metal, on which steps are fixed, in particular made of concrete or wood.

• ▪ des contremarches ;
• ▪ des zones de réception et de fixation des marches, et plus précisément des plateaux de marche.

Thus, according to the invention, the support beam constituting the stringer consists of at least one folded sheet, typically made of steel, defining:

• ▪ risers;
• ▪ areas for receiving and fixing the steps, and more specifically the walking platforms.

Thus according to the invention, the staircase comprises a quarter-turn, which comprises a stringer made up of a single metal beam produced by cutting and folding at least one sheet metal in particular of steel, so as to define at least four zones for receiving the walking platforms, capable of ensuring the quarter turn, the walking platforms being made of concrete or wood, at least four of which are adapted to said four stringer zones to ensure the quarter turn.

In other words, the invention consists in providing a single support beam constituting the stringer, produced by cutting and folding at least one steel sheet, or even several, these cutting and folding operations making it possible to vary the height of the steps on the one hand, and by design also makes it possible to vary the lap due to the chosen positioning of the walking platforms on said stringer.

According to a first embodiment of the invention, the metal beam constituting the stringer consists of a single metal sheet, cut then folded, so as to define the bottom of the stringer as well as two lateral wings.

According to the invention, the reception zones defined by the stringer for the walking platforms comprise a first support and bonding zone for said walking platforms, and a second zone defining a notch oriented along an essentially vertical plane of width corresponding substantially at the thickness of the step plate, notch within which said plates are capable of sliding over a greater or lesser distance depending on the desired lap. In doing so, the superposition of the walking platforms can be varied at the level of the quarter turn relative to each other according to the desired overhang at the collar level. As a reminder, the collar is the narrowest part of the steps of a spiral staircase, in particular a spiral staircase.

Alternatively, the walking plates may not be glued to said first support zone, but fixed reversibly, by bolting for example, said plates to a plate fixed to the metal beam. The walking platforms are then provided with one or more threaded inserts, passing through orifices correspondingly positioned within the plate.

In the configuration in which the treads are glued to the support area of the riser, each of the treads has on its lower surface, that is to say on its bearing face, a notch or recess able to cooperate with a corresponding projection, emanating from the riser.

Said risers are also made of metal, and fixed between the two aforementioned lateral wings, in particular by welding.

According to a second embodiment, the beam constituting the stringer is not produced from cutting and bending into a U shape from a single sheet, but from cutting, bending and assembling of two separate L-shaped sheets. This assembly is carried out in particular by welding. The two sheets thus welded define the bottom of the stringer and its lateral wings. The two lateral wings which result from folding and cutting then define an area for receiving the walking platforms.

This second embodiment makes it possible to significantly reduce the width of the stringer and therefore the bulk associated with such an installation.

The ends of the two lateral wings, according to this second embodiment, are folded in the direction of one another, in order to form a riser which is then found integrated into the beam. The edge of the free ends of the wings, after folding, can be secured to one another, in particular by welding.

When the step plates are intended to be glued, they present by molding or by cutting, a projecting zone extending in the plane of said plate, this projection acting as a shoulder capable of being received between the two lateral wings of the stringer. . According to the second embodiment, bearing and securing surfaces of the walking platforms or plates are then fixed in the vicinity of the free end of the two lateral wings. The walking platforms are then fixed to the stringer by bolting to these surfaces.

According to the invention, straight sections of the staircase can be joined to the two ends of the quarter-turn and for this purpose, the stringer comprises several sections of beams assembled to each other in particular by bolting. The connection between the different sections of beam is carried out by means of two plates and bolts.

BRIEF DESCRIPTION OF THE FIGURES

• La figure 1 est une représentation schématique en perspective de l'escalier quart tournant conforme à un premier mode de réalisation de l'invention.
• La figure 2 est une représentation schématique en perspective du limon de l'escalier de l'invention selon le premier mode de réalisation.
• La figure 3 est une représentation schématique en plan illustrant le positionnement des plateaux de marche sur le limon selon le premier mode de réalisation.
• La figure 4 est une représentation en plan supérieur illustrant notamment la superposition des plateaux de marche d'un escalier de facture traditionnelle et d'un escalier conforme à l'invention toujours selon la même mode de réalisation.
• La figure 5 illustre l'assemblage de deux tronçons du limon, respectivement le limon du quart tournant et le limon d'une section droite.
• La figure 6 est une représentation schématique en perspective du limon selon un second mode de réalisation de l'invention.
• La figure 7 est une représentation schématique en perspective d'un plateau de marche vue de sa face interne en cours de fixation sur le limon.
• La figure 8 est une vue analogue à la figure 7, ledit plateau étant alors complètement fixé sur le limon.

The manner in which the invention can be implemented and the advantages which ensue therefrom will emerge more clearly from the embodiments which follow, given by way of indication and not limiting in support of the appended figures.

• The figure 1 is a schematic perspective representation of the quarter-turn staircase according to a first embodiment of the invention.
• The figure 2 is a schematic perspective representation of the stringer of the staircase of the invention according to the first embodiment.
• The figure 3 is a schematic representation in plan illustrating the positioning of the walking platforms on the stringer according to the first embodiment.
• The figure 4 is a representation in upper plan illustrating in particular the superposition of the treads of a staircase of traditional invoice and a staircase in accordance with the invention always according to the same embodiment.
• The figure 5 illustrates the assembly of two sections of the stringer, respectively the quarter-turn stringer and the cross-section stringer.
• The figure 6 is a schematic perspective representation of the stringer according to a second embodiment of the invention.
• The figure 7 is a schematic perspective representation of a walking plate seen from its internal face being fixed on the stringer.
• The figure 8 is a view analogous to the figure 7 , said plate then being completely fixed on the stringer.

DETAILED DESCRIPTION OF THE INVENTION

We have represented within the figure 1 a schematic perspective view of the quarter-turn staircase (1) according to a first embodiment of the invention. As already said, this staircase is of the prefabricated type, in the sense that it includes a stringer independent of the walking platforms.

In the context of the invention, the stringer is metallic. Once produced, it is moved to the site and placed, and independent walking platforms (18) are attached and fixed to said stringer once it has been fixed. Typically, the walking platforms are made of concrete by molding but can also be made of wood by cutting.

The stringer (2) consists of a metal beam, produced, according to this first embodiment, from a single sheet of steel cut flat, for example using a numerically controlled machine. Once cut, this sheet is folded into a U shape in order to define the bottom (3) of the stringer, as well as two lateral wings (4 and 5), extending substantially perpendicular to the bottom (3).

These lateral wings (4, 5) have cutouts so as to each define a notch (6), extending substantially in a vertical plane, and the function of which will be described later.

As can be seen on the figure 2 , said lateral wings (4) and (5) have cutouts such that they define at their upper free edge, resulting from the cutting of the sheet metal making up the stringer, a horizontal support surface for the walking platforms.

Furthermore, still according to this first embodiment, a riser (7), also made of metal, extended by a horizontal support (8) and bonding surface, is fixed between said lateral wings (4 and 5), in particular by welding.

It is easy to see that by acting on the numerically controlled cutting machine ensuring the cutting of the sheet metal making up the stringer (2), it is possible to act on the height of the risers in a simple manner, and thus define the desired staircase in terms of such characteristics.

The abovementioned bearing surfaces (8) also serve to receive the walking platforms at the level of which these are glued. Advantageously, the front area of the risers has an upward projection or protrusion (9) capable of cooperating with a complementary groove formed on the underside of the walking platforms in order to optimize the stability of the positioning of the latter on the silt.

According to another embodiment of the invention, more particularly described in relation to the Figures 5 to 7 , the stringer is no longer formed of a single sheet cut out then folded into a U shape, but of two sheets (24) and (25), cut out and folded into an L shape. The method of cutting and folding is based on the same principle as that mentioned in connection with the first embodiment.

The two L-shaped sheets thus formed are assembled, in particular by welding, at their horizontal bar in order to form the bottom of the stringer (23). The free ends of the two lateral wings are folded in the direction of one another, in order to bring their extreme edge into contact, the latter also being able to be joined to one another, in particular by welding. They thus form a riser (26).

According to the same principle as described above, the cutting of the two plates (24) and (25) promotes the positioning of the walking platforms and makes it modular.

Support and fastening surfaces (28) or plates pierced with through orifices (27) are then welded in the vicinity of the free ends of the two lateral wings in order to accommodate the walking plates. These are provided with threaded inserts, able to pass through the orifices (27) of the plate (28), and each to receive a fixing bolt. Alternatively, screws (31) are inserted into threaded threads formed within the underside (30) of the step plate after passing through said orifices (27) of the plate (28). In order to facilitate the positioning and then the fixing of the step plate on the plate, the two anterior holes of the latter are replaced by through-holes (32), making it possible to slide said step plate already provided with the two corresponding screws (31) not completely screwed. When the step plate is correctly positioned on the plate, we then bolt completely, with the third screw screwed into the hole (27): see Figures 7 and 8 .

With regard to these walking platforms, within the framework of the quarter-turn staircase of the invention, it is necessary to make at least four of them, of different shapes, to adapt to the turn resulting from the quarter-turn. We observe these walking platforms in plan on the figure 4 illustrating these different forms. More specifically, the step plate (10) is fixed and of determined size.

The other three steps (11, 12 and 13), as well as the step (10) are also made by molding and have different shapes.

Anyway, each of these walking platforms has, when it must be fixed by gluing, a projecting area (respectively 14, 15, 16 and 17) obtained by molding or by cutting, of length corresponding to the spacing between the two lateral wings (4 and 5), defining a shoulder for the purpose of being received between said lateral wings (4, 5), as can be seen on the figure 4 and here again favoring the stability of the positioning and of the fixing of said walking plates within the stringer (2).

In addition and as already indicated, the thickness of the walking plates (10, 11, 12, 13, 18) corresponds to the clearance close to the width of the notches (6) defined by the lateral wings of the stringer (2).

Thus, apart from the walking platform (10) which is fixed, due to the fact that it has the shape corresponding to the angle between two adjacent walls at the level of which the staircase is installed, the other walking platforms can slide from more or less important within said notches (6), to allow to vary the lap of the staircase at the turn and in particular to maintain a constant lap on the stride, that is to say , according to the definition resulting from standard EN 14843, the conventional line representing the usual trajectory of staircase users.

We have in fact represented within the figure 3 by arrows the direction of superposition of the walking plates and in particular concerning the upper walking plates (11 and 12) in the direction of the fixed step (10) and the lower plate (13) again in the direction of the fixed step (10 ).

This degree of superposition of the walking platforms is also established as a function of the desired overhang at the collar.

Furthermore and as we have represented in figure 5 , the quarter turn staircase area described above can be connected to straight staircase areas. To this end, a stringer is used, also consisting of a metal beam of the type described above, but this time linear, bolted (33) to the stringer (2) in order to ensure cohesion to the assembly. The walking platforms then put in place on these straight sections are of standard and constant format, their fixing and positioning being on the other hand similar to those described in relation to the description above.

We understand all the interest of the staircase according to the invention insofar as it allows in a simple way to have a quarter-turn staircase with adjustable tread height of the steps also adjustable.

In addition, the optimization is also conceived in terms of ease of movement and installation due to the relatively reduced weight of the stringer and of the walking platforms which are fixed on said stringer.

Claims (10)

1. Prefabricated staircase with a quarter turn comprising a central stringer (2) to which are singly attached to the treads (10 - 13, 18), the central stringer (2) being made of a metal beam manufactured by cutting and bending of at least one metal sheet, in particular made of steel, so as to define at least four zones receiving the treads, suitable to provide the quarter turn, the said receiving zones comprising a first zone for supporting and possibly bonding the said treads, and a second zone defining a notch (6, 29) orientated along an essentially vertical plane and having a width corresponding substantially to the thickness of the tread, within which notch the said treads are capable of sliding over a variable distance - depending on the desired tread area;
   ▪ the treads are made of concrete or wood, of which at least four are adapted to the said four zones of the stringer to obtain the quarter turn.
2. Prefabricated staircase according to the claim 1, characterised in that the stringer (2) is obtained from the cutting bending into a U-shape of a single metal sheet, the sides (4, 5) resulting from the bending and cutting thus performed defining a zone for receiving the treads.
3. A prefabricated staircase according to claim 2, characterised in that it also comprises risers (7), also made of metal, and welded into the metal beam forming the stringer between the sides (4, 5).
4. A prefabricated staircase according to claim 3, characterised in that on the underside of each of the treads i.e. on its bearing face, there is a notch or groove designed to match a corresponding protrusion, made in the risers (7).
5. A prefabricated staircase according to claims 2 to 4, characterised in that the various treads have, by moulding or cutting, a protruding area acting as a shoulder which can be received between the two wings (4, 5) of the stringer, resulting from the bending of the sheet metal forming the stringer.
6. A prefabricated staircase according to the claims 1 and 2, characterised in that the stringer (2) is obtained from the cutting, bending and assembly, in particular by welding, two L-shaped metal sheets, defining after welding, the base (23) of the stringer and the sides (24, 25) resulting from the bending and cutting process, defining a zone for receiving the treads.
7. A prefabricated staircase according to claim 6, characterised in that the free ends of the sides (24, 25) are bent towards each other and possibly joined together, in particular by welding, to form a riser (26).
8. A prefabricated staircase according to one of claims 6 and 7, characterised in that the stringer (2) receives a bearing and connecting plate (28) or surface for supporting and securing the treads, attached near the free end of the sides (24, 25).
9. A prefabricated staircase according to claim 8, characterised in that the treads are attached to the stringer by bolting to the bearing and connecting plate (28).
10. A prefabricated staircase according to one of claims 1 to 9, characterised in that the stringer comprises several beam sections assembled together, in particular by bolting.

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