FR3066516B1 - HEXAGONAL HELICOIDAL STAIRCASE STAIRCASE MODULE, TOGETHER WITH AT LEAST ONE SUCH MODULE AND STAIRCASE COMPRISING AT LEAST ONE SUCH ASSEMBLY - Google Patents

Abstract

The module (1) for a hexagonal helical modular staircase, with six vertical corner uprights around a vertical central upright, comprises a vertical central pole (2) and two triangular horizontal steps (3, 4), one of which is low and one high, secured to the central post (2), a stringer (7) and two corner posts (10, 11) parallel to the central post (2), and one of which said front corner post (10) ) is integral with the stringer (7) and the low step (3), and the other said rear corner post (11) is integral with the stringer (7) and the top step (4), the three poles (2, 10, 11) of the module each having a female end and a male end adapted to receive a male end and to be received in a female end of the identical module posts (1) to contribute with the latter to the constitution of the amount central and corner uprights of the stairs.

Description

The invention relates to the field of helical or rotary modular staircases, indoor or outdoor, allowing the displacement of a staircase. between a low area and a high stair installation area, which is not built-in or associated with scaffolding, and generally does not constitute a workstation, or is not associated with such a station, but only allows access from the ground, or a low level, to serve a single high level, or vice versa.

More particularly, the invention relates to a modular spiral staircase of hexagonal horizontal cross section, which can be mounted by non-professional persons, from a set of modular elements, the assembly including in particular at least one module staircase with two steps, and preferably a plurality of such modules identical to each other, all the modular elements of the assembly allowing the construction of the staircase being light enough to be easily handled by non-specialized personnel to the assembly of a helical modular staircase of a simple and economical structure, by the implementation of a simple assembly process by repeated cycles. The staircase according to the present invention does not include a keystone or keystone, as for most scaffolding, and its assembly does not require that the assembly staff has followed a training, without jeopardizing the security, the course of assembly as when using the helical staircase, which is not a temporary staircase. For this purpose, the invention proposes a stair module, for a modular helical staircase of hexagonal horizontal cross section, delimited by six vertical corner uprights around a vertical central upright, said module comprising a central pole of axis substantially vertical and two substantially triangular shaped steps, including a low step and a high step, extending in horizontal planes perpendicular to the axis of the central post and radially from said central post, to which the steps are each secured by an edge narrow internal radial end, and which is characterized in that said two steps are each secured by a wide edge of outer radial end to a single stringer in the form of a substantially flat plate and parallel to the axis of the pole central, the silt having a lower portion and an upper portion secured to the edge of the wide edge respectively of the low step and the mar high, and in that the module comprises two poles of axes angle parallel to the axis of the central pole, so that the lower ends of the three columns of the module are in a transverse plane perpendicular to the axes of the three poles of the module, and one of the two corner posts, said front corner post, is integral with the lower part of the stringer at the front end of the latter, the nose of the low step at its outer radial end, and the wide edge of the low step, at its front end, and the other corner post, said rear corner post is secured to the upper part of the silt at the rear end of the latter, the rear edge from the high step at its outer radial end, and the wide edge of the high step at its rear end, the central post and the two corner posts of the module each having a female end and a male end which are respectively adapted to receive a male end and to be received in a female end of similar posts of identical modules with two steps, so as to contribute with said posts similar to the constitution of said central post and said corner posts of the staircase.

Advantageously, in an embodiment that provides a high resistance for a limited weight, and a great ease of assembly, the stair module is such that the central post and the two corner posts are three identical tubular posts one to the other, secured to the two steps and the common stringer, and whose upper ends are each extended by one respectively three male tips, each in the form of a sleeve, retained partially fitted in a corresponding post and partially in projecting above said post, at the male upper end of said corresponding post.

In particular, to limit the weight while promoting a durable assembly of the staircase, the module is preferably such that the three posts of said module are metal or light alloy and secured at least by welding to the steps and the slime which are in the same metal or alloy, each of the three male end pieces being a retained steel sleeve, by its lower end portion, at least by screwing into a corresponding post, and having a projecting upper end portion, above said corresponding post , and preferably drilled with radial screw holes, the lower end portion of each post being also pierced with at least one radial screw hole.

Preferably, to facilitate the mounting of the modules on each other and on the other modular elements of the staircase, it is advantageous for the male end of the front corner post to protrude above the upper end of the staircase. pole corresponding to a greater height than the male ends of the rear corner post and the central post, which are identical and protrude from the same height above the corresponding posts. Thus, a partial engagement of a stair module or other modular element on this male end of the front corner post of a module allows, on the one hand, by rotation about the axis of this post angle before, to pre-orient and preposition more easily another member to be mounted on the stair module considered, on the one hand, and, on the other hand, the male end of a greater height of front corner post allows a better vertical support of other uprights of corner post, which are associated with the stair module according to the invention in the assembly of the helical staircase.

Advantageously also, to ensure good resistance to the stair module without hindering a side exit or side entrance to a user at the top of the staircase, the stringer has a substantially rectangular bottom portion with lower and upper edges substantially parallel to the step low, and an upper portion substantially U-shaped returned, upper edge substantially parallel to the high step. This realization of the silt also allows to present, at the connection between the lower part of the silt and the adjacent branch of the U returned from the upper part of this silt, a sufficiently large surface for the display, by any appropriate means (gluing, painting or other marking) of assembly instructions.

So that the spiral staircase hexagonal section takes up a limited space, for example in a circular cylinder diameter of less than 2 meters, while allowing to stack identical modules on each other so that any of the three posts of one module can be stacked on any of the three posts of another module, and simultaneously, the two steps of each module have a support surface or comfortable support the parallel axes of the three columns of the module each pass through one respectively of the three vertices of an equilateral triangle in a transverse sectional plane of the module perpendicular to the axes of said posts, and each step has a substantially rectangular plan shape . The invention also relates, in a second step, to a set of modular elements, for producing the helical modular staircase of hexagonal horizontal cross-section delimited by six vertical corner uprights around a vertical central upright, this assembly being characterized in that at least one modular element among said modular elements of the assembly is a staircase module with two steps as presented above, at least one second modular element among the modular elements of the assembly being a guard -Body comprising two tubular vertical uprights of unequal length, braced at the bottom by a horizontal cross member and at the top by at least one, but preferably two, cross (s) inclined (s) forming smooth (s) protection , each of the two railing posts supporting, projecting outwardly from the side, a sleeve at the bottom and a tenon projecting upwards at the top, which are have parallel to the amount of guardrail, said sleeve being adapted to be fitted on the upper end of the rear corner post of a stair module or on a post of a corner post constituting another element modular said assembly, said tenons being adapted to be housed in lateral sleeves angle post posts of the assembly. Such railing thus mounted in a side face of the hexagonal staircase which is delimited by the rear corner post on which one of its two sleeves is mounted, and the corner post post on which l other of its sleeves is mounted, prevents the fall of a user over the silt coming to be positioned in this side face of the staircase, when a next stair module has been mounted on the one whose rear corner post supports one of the railing sleeves. The set of modular elements according to the invention advantageously also comprises a plurality of corner post columns comprising: a first post, of substantially the same structure and dimensions as the front corner post of the staircase module with two steps, and having female and male ends compatible respectively with the male and female ends of said posts of said module, but with, in addition, an annular collar forming a stop limiting the fitting of a guardrail sleeve on said first post, and an external lateral projection fastener, adapted for detachable connection with a free end of a hinged hinge at its other end to another corner post post, a second post, of the same structure as the first post of a post post. angle, but of double height of that of said first corner post pole, a third post, of the same structure as the first post of angle post but of height tripl e of that of said first post of corner post, and at least one fourth post, also of the same structure as the first post of corner post, but of height quadruple that of said first post of post post, the second third and fourth corner post posts further having a rectilinear rail hinged by a pivot end about a horizontal axis on said post post post substantially along the length of the first post from the top end thereof; and adapted to be releasably connected, at its other end, in inclined strut, to said fastener of a neighboring corner stud post delimiting a same face of the hexagonal staircase, and said at least one fourth stud post angle having further, projecting laterally on either side of a portion of said post in its lower half, two sleeves, parallel to said fourth pole, and adapted to each receive a tenon guard- body, so that said smooth inclined spacer of a fourth post angle post is adapted to act as additional safety rail added to the or both inclined smooth railing previously mounted on the 'staircase.

In order to also ensure the safety of the users at the upper end of the spiral staircase, the set of modular elements for the construction of the staircase also comprises an additional modular element arranged as a railing for closing the staircase. staircase, comprising two tubular, straight, parallel and equal height railing posts, braced by at least two horizontal rectilinear rails, rigidly connected, at each of their two ends, to one respectively of the two guardrail posts , including a top rail connecting the two upper ends of the two railing posts, and at least one middle rail, so as to form a rectangular frame open between the lower ends of these two uprights, said closing railing also comprising in the lower part of the uprights and projecting outwards, two collars each connected to one of the two uprights, and capable of s to be mounted removably one around the central upright and the other around a corner post of the staircase, in the middle part of the uprights and outwardly projecting outwards, two sleeves each bound to the one of the two uprights and of axis parallel to the latter, and adapted to be removably mounted on the central and rear angle columns of another stair module of said assembly, and preferably in the upper part of the two uprights of the closing railing, two pins projecting upwards and adapted to be mounted in corner post pillar sleeves of said modular assembly. The other stair module on which the closing railing is mounted by its two sleeves is the last module with two steps of the staircase, in the direction of the climb, that is to say the highest , the exit of the staircase or its entrance, at the top end of this staircase, being over the mud of this last stair module.

To ensure a good horizontal mounting of the steps, in particular the first stair modules which are mounted, and excellent rigidity of the staircase at its base, it is advantageous that the set of modular elements according to the invention also comprises , as additional modular elements, two foot jacks, each of which is capable of adjusting in height one respectively of the two corner posts of a first stair module with two steps, and a substantially horizontal trapezoidal base, whose small base and two inclined sides are of the same length corresponding to one side of the hexagonal section of the staircase, and produced by the assembly of rectilinear tubular sections constituting at least the two bases and the two inclined sides of the trapezoidal base, which is equipped with a foot cylinder at each of its four vertices, and adapted to adjust in height angle post posts delimiting three adjacent faces; the fifth hexagonal horizontal cross section of the helical modular staircase, a fifth foot jack equipping the middle of the large base of the trapezoidal base for the height adjustment of the central pole of said first stair module with two steps. Thirdly, the invention relates to a modular spiral staircase of hexagonal horizontal cross-section, delimited by six vertical uprights around a vertical central upright, and comprising a set of modular elements specific to the invention and as defined above, whose modular elements are assembled to each other. The invention relates, in a fourth time, to an advantageous method of mounting a helical modular staircase according to the invention, this method being characterized in that it comprises a succession of cycles each comprising three stages, the first of which is the arrangement of a two-step stair module on the ground or on an identical module and a post post post previously arranged, and such that the two corner posts of said stair module define a face of the hexagonal horizontal cross-section staircase, the second stage of which is the arrangement of a corner post post, on the floor or on another identical module previously arranged, such that said post post delimits with the rear corner post of said stair module an adjacent face of the hexagonal staircase, and whose third step is to mount a railing, fitted by one of its two bottom sleeves on said corner post post and the other of the two sleeves on said rear corner post of said stair module, so that the guard rail extends into said adjacent face of the hexagonal staircase. The advantage of this process is that every cycle a guardrail is mounted before the two-step module is mounted, the silt of which is placed in the same side of the staircase as the guard. body considered.

When a trapezoidal base, as defined above, and two independent foot cylinders are used to ensure proper mounting of the base of the helical staircase, the method according to the invention is such that its first cycle consists of mounting , in its first step, a first stair module by each of its corner posts on one respectively of the two independent foot cylinders, defining a first side face of the hexagonal staircase, and by its central pole on a foot jack mounted in the middle of the large base of said trapezoidal base, then, in its second step, to mount a first post of angle post on the foot jack mounted on the end of the large base of the base in the direction of rotation of the staircase, then, in its third step, to mount a first guardrail by its sleeves on the rear corner post of said first stair module and on said first post post of angle, defining a second side face of the hexagonal staircase, and then reproducing a second cycle, consisting, in its first step, of mounting a second stair module on the first, by mounting the front corner post of the second module on the rear corner post of the first module, the central post of the second module on and in the extension of the central post of the first module, and the rear corner post of the second module on the first post of the corner post, then, in its second step, mounting a second corner post post, twice the height of the first corner post post, on a foot jack mounted on the top of the small base of the trapezoidal base which is closest to the first post of the corner post, and to connect the free end of its rail to said first post of angle post, so as to stiffen the assembly and delimit, by said first and second post uprights; angle, a third side face of the hexagonal staircase, and then, in its third step, to mount a second guardrail in this third side face of the staircase, by inserting one of the sleeves of said second guardrail on the second angle post post and the other sleeve on the rear corner post of the second module, then to reproduce a third cycle, the first step of which is to mount a third stair module by mounting its front corner post on the rear corner post of the second module, its central post on and in the extension of the central post of the second module, and its rear corner post on the second post of the corner post, then, in its second stage, mounting a third corner post post, at a height equal to three times the height of the first corner post post, on a foot jack mounted on the other top of the small base of the trapezoidal base, and to connect the extremi free of its smooth to said second post of angle post, so as to stiffen the assembly and delimit a fourth side face of the hexagonal staircase by said second and third posts of corner post, and to finish this third cycle by its third step, by mounting a third railing, one of which is fitted on the upper end of the third corner post pole, and the other sleeve on the rear corner post of the third module staircase, then to complete a fourth cycle, the first step of which is to mount a fourth stair module by mounting its front corner post on the rear corner post of the third module, its central post on and in the extension of that of the third module, and its rear corner post on the upper end of the third corner post pole, then, in its second stage, to mount a fourth corner post pole, a high which is four times that of the first corner post pole, on a foot jack mounted on the second top of the large base of the trapezoidal base, and to connect its rail to the third post of angle post, so as to stiffen the assembly and delimit a fifth face of the hexagonal staircase, and to finish this fourth cycle by its third step, by mounting a fourth guardrail, a sleeve is fitted on the upper end of the fourth pole of angle post, and the other sleeve is fitted on the rear angle post of the third module, and so on until the desired height of the staircase is reached, each tower of which consists of the assembly of six modules staircase with two consecutive steps, the use of six corner post columns and six guardrails.

Thus, in a preferred embodiment, the helical staircase comprises twelve modules with two steps, or twenty-four steps in all, and rises to a maximum height of about 5 meters.

The method of mounting such a staircase is such that from the fifth cycle, all the corner post posts mounted in the second stage of the cycles are identical to the fourth corner post post, and each post post angle is mounted on and in the extension of a corner post before an underlying stair module.

Likewise, starting from the seventh cycle, the two lateral sleeves of each post of corner post are moved on the vertical studs projecting from the side of two adjacent pre-mounted adjacent railings, so as to stiffen the structure of the staircase.

Finally, starting from the seventh cycle, it is advantageous that the rail of each corner post post is fixed by its free end to the post post column previously mounted in an inclined spacer substantially parallel to the rail (s). ) inclined (s) of an underlying railing previously mounted, so as to act as third inclined smooth. Other advantages and features of the invention will emerge from the description given below, without implied limitation, of an exemplary embodiment described with reference to the accompanying drawings in which: - Figure 1 is a perspective view of a stair module with two steps according to the invention, - Figures 2 and 3 are plan views respectively of the low step and the high step of the module of Figure 1, - Figure 4a is an elevational view side of the module of Figure 1, the side of the stringer in the outer face of this module, which corresponds to a side face of the spiral staircase of hexagonal section according to the invention - Figure 4b is a view similar to the figure 4a of a variant of the module of FIG. 1; FIG. 5a is a side elevational view of each of the three unmounted columns of the module of FIGS. 1, 4a and 4b; FIG. 5b is a side elevational view of FIG. 'a tip fit to be fitted and retained dan s the upper end portion of a pole according to Figure 5a, so that an upper end portion of the tip is projecting out of the upper end of the pole, shaped as a male end, for a male connection / Female with other elements or modules of the staircase according to the invention - Figures 6, 7 and 8 are three perspective views each representing one of three stacking modes for storing two stair modules FIG. 9 is a side view of a railing, which is a modular element of a set of modular elements for making a helical staircase of hexagonal horizontal cross-section delimited by six uprights. vertical angle around a vertical central upright according to the invention, - Figure 10 is a side elevational view of a first post of angle post of said set of modular elements according to the invention, this first post d e angle post having substantially the same structure and dimensions as at least one of the three posts of a stair module with two steps, and in particular that the front corner post, secured to the low step and the silt of the stair module, and in the variant of the module according to Figure 4b, - Figure 11a is a view similar to Figure 10 for a second post angle post which is a modular element of said assembly according to l invention, this second post being substantially of the same structure as the first post of angle post of Figure 10, but double height of that of said first post of angle post, and with in addition a smooth articulated by one end on the second post, substantially halfway up the latter, FIG. 11b is a view similar to FIGS. 10 and 11a for a third post of angle post, of the same structure as the second post of post post. Figure lia, but of trip height 1e of that of said first corner post post of FIG. 10; FIG. 11c is a view similar to FIGS. 10, 11a and 11b for a fourth post of corner post, belonging to the set of modular elements according to the invention, also of the same structure as the second and third corner post columns of FIGS. 11a and 11b, but of height four times that of the first corner post post of FIG. 10, and at the bottom , with two sleeves projecting laterally on either side of the fourth post of angle post, these sleeves being parallel to this fourth post and able to each receive a railing post, such as those mounted in the upper part on the amounts of the railing of Figure 9, - Figure 12 is a view similar to Figure 9 for a railing closure, adapted to be mounted at the upper end of a staircase according to the invention at the level of from the back edge of the high step of the last module of escali er mounted, to border the outlet or the upper entrance of the staircase, over the stringer of said last mounted stair module, - Figure 13 shows schematically in side elevation a foot jack, to support and adjust height one of the corner posts of the first stair module installed, - Figure 14 is a perspective view of two independent foot cylinders according to Figure 13 associated with a trapezoidal base whose four vertices at the ends of its small and large bases, as well as the middle of the large base, are equipped with five foot jacks integral with said base, - Figures 15a, 15b and 15c represent successively three steps of a simple cycle of mounting a first module d staircase according to the invention, this cycle repeating very substantially for all the stair modules used, except for the last one, because of the mounting of the closing railing and the adaptations necessary to develop in any security the exit or upper entrance of the staircase over the stringer of the last assembled stair module, - figures 16a, 16b and 16c represent the three successive stages of the assembly cycle of the second stair module, - figures 17a, 17b and 17c are similar to FIGS. 16a, 16b and 16c for the three stages of the assembly cycle of the third stair module; FIGS. 18a, 18b and 18c, 19a, 19b and 19c, and 20a, 20b and 20c show similarly, the three steps of the successive mounting cycles respectively of the fourth, fifth and sixth stair modules, - FIG. 21 is a figure similar to the previous ones and showing the staircase (being assembled) at the end of the second step of the mounting cycle of the tenth stair module, and - Figure 22 is a similar figure to the previous and representing the staircase whose assembly is completed, in the last stage of the last cycle during which the twelfth module of steps was mounted.

To achieve a modular helical staircase of hexagonal horizontal cross section and delimited by six vertical corner uprights around a vertical central upright, the invention proposes a base module 1, as shown in FIGS. 1 and 4a, with three tubular cylindrical poles, of parallel axes, supporting two steps whose bearing surfaces extend in planes perpendicular to the axes of the columns, and a stringer bordering the steps on one side corresponding to one of the six outer lateral faces of the staircase. One of the posts is called central post 2, because it participates in the constitution of the vertical vertical column of a staircase by the vertical stack and in the extension of each other of the central posts 2 of all the modules 1 used for the mounting a staircase, as described below with reference to Figures 15a to 22.

The two steps are a low step 3 and a high step 4, each in the form of a right-angled triangle, seen in plan, as shown respectively in FIGS. 2 and 3, and each extending in one of two parallel planes respectively, radially relative to the axis Z, vertical in the position of use, the central post 2, to which each step 3, 4 is secured by its inner radial end at a narrow edge 5 in an arc corresponding to the outer diameter 2. Each step 3, 4 is also secured by a wide edge 6, at its outer radial end, to the stringer 7, consisting of a flat plate parallel to the axis Z of the central pole 2, and having a portion low 8, substantially rectangular lower and upper edges substantially parallel to the low step 3, and secured to the edge of the broad edge 6 of the low step 3, and a high portion 9, substantially U-shaped returned, with upper edge direction iably parallel to the upper step 4, and secured to the edge of the wide edge 6 of the high step 4. The assembly consisting of the central post 2, the two steps 3 and 4 and the stringer 7 is also secured to the other two poles, which are corner posts, contributing to the constitution of the corner posts of a hexagonal staircase, during assembly of the plurality of modules 1 which this staircase comprises, as also described below with reference to FIGS. 15a to 22 One of these two corner posts is called the front corner post 10, and the other rear corner post 11, because they are integral, the first one 10 at the front of the low step 3, the second 11 at the rear of the upper step 4, and both to the stringer 7. More specifically, the front corner post 10 is integral with the nose or front edge 12 of the low step 3 at its outer radial end and of the wide edge 6 of this low step 3 at its front end, and this front corner post 10 is also secured to the lower part 8 of the stringer 7, at the front end thereof. The rear corner post 11 is integral with the rear edge 13 of the upper step 4 at its outer radial end, and the wide edge 6 of the upper step 4 at its rear end, and the rear corner post 11 is also secured to the upper portion 9 of the stringer 7 at the rear end thereof, at a small arcuate edge which intersects the other non-right vertex of the corresponding right triangle in Figure 2 for the low step 3 and in FIG. 3 for the high step 4.

The three posts 2, 10 and 11 of each module 1 comprise identical sections of cylindrical metal tube of circular section, for example 400 mm in length, with an outer diameter of 48.6 mm and a thickness of 4 mm. , whose lower ends are located in the same plane perpendicular to the axes of the posts 2, 10 and 11, this plane being horizontal in the use position and, optionally, also storage, the module 1 (see Figure 5a). The upper ends of the tube sections of the posts 2, 10 and 11 are also in the same plane perpendicular to the axes of these posts, and each section of tube is extended upwards by a male end 14, having the shape of a sleeve cylindrical metal of circular section, as shown in Figure 5b, whose dimensions are smaller than those of the tube sections (and are for example 200 mm long, 39 mm outside diameter and a thickness of 2 mm), so that each end piece 14 can be partially fitted with its lower part retained in the upper part of the corresponding tube section, in which the end piece 14 is retained by a bolt or a screw 15 passing through the bores 15a and 15b facing in a post 2, 10 or 11 and a tip 14, so that a length of about 47 mm from the upper part of the tip 14 projecting above the upper end of the tube section of post 2, 10, 11 corresponding. Thus, each post 2, 10, 11 has a lower end arranged at the female end and an upper end arranged at the male end, which are respectively adapted to receive the male upper end and to be received in the lower female end of the male end. any of the posts 2, 10 and 11 similar of other modules 1.

To secure the interlocking of the posts 2, 10, 11 of different modules 1, and / or other modular elements, described below, for the realization of a staircase, and in particular corner post columns described in Referring to Figures 10 to 11c, the projecting upper end portion of the male tips 14 is drilled with radial screw holes 16, and the lower end portion of each post 2, 10, 11 is also pierced with a hole 17. radial screwing, which can cooperate with one of the holes 16 of the tip 14 of a pole 2, 10 or 11 of another module 1 to receive the same screw or the same bolt connection.

Each endpiece 14 may be a steel sleeve while the tube sections of the posts 2, 10 and 11 are, like the stringer 7 and the steps 3 and 4, made of a metal or light alloy, for example aluminum, the posts 2, 10 and 11 being secured to the steps 3, 4 and the stringer 5 at least by welding, the stringer 7 being for example an aluminum sheet 3 mm thick and the steps 3 and 4 being made in a sheet metal to aluminum checkerboard with a thickness of 3 to 4.5 mm.

A basic module 1 thus produced can have a weight limited to 12 kg, easy to transport, handle and position for the assembly of the staircase.

FIG. 4b shows a preferred embodiment of the module 1, which differs from the module of FIGS. 1 and 4a only in that the tip 14 of the front corner post 10 is of greater length than the end pieces. 14, which are identical, of the other two posts 2 and 11, and thus protrudes above the upper end of the pipe section of the post 10 to a height, for example 145 mm, larger than the male end caps 14 of the central post 2 and the rear corner post 11, projecting from the same height above the latter posts. Thus, the module according to FIG. 4b facilitates the relative positioning of a module mounted on a module previously set up by a partial engagement of the female part of a post of the newly installed module on the elongate end 14 of the post. front angle 10 of the module already laid, then, by pivoting about the axis of the elongated tip, the newly installed module can be oriented in a horizontal plane to facilitate assembly, and, moreover, such an elongated tip , equipping the compatible ends of the corner post columns described below with reference to FIGS. 10 to 11c, allows a better vertical retention of these corner post posts when they are fitted on such elongated end pieces, during the mounting of the staircase as described below with reference to Figures 15b and following.

But, in the two embodiments of FIGS. 4a and 4b, the parallel axes of the three posts 2, 10, 11 of each module 1 each pass through one respectively of the three vertices of an equilateral triangle, in a sectional plane. transversely of the module 1, perpendicular to the axes of these posts 2, 10, 11. Thus, two or more modules 1 can be stored stacked one on the other, since the different modules 1 are identical and that thus any of the three posts 2, 10, 11 of a second module 1 can be fitted by its lower female end to the male upper end portion with end 14 of any of the three posts 2, 10 and 11 of a first module 1 on which the second module is stacked.

Thus, it is possible to store two superposed modules 1 according to one or the other of the three positions shown in FIGS. 6, 7 and 8. In FIG. 6, the two central columns 2 of the two modules 1 are superposed in the vertical extension of each other, as well as the two front corner posts 10 and the two rear corner posts 11. By a rotation of the upper module 1 of 120 ° about a vertical axis passing through l intersection of the mediators of the corresponding equilateral triangle, in the counter-clockwise direction, can be brought the two modules in the stacked position of Figure 7, wherein the central pole 2 of the upper module is fitted on the rear corner post 11 of the lower module, the rear corner post 11 of the upper module being fitted on the front corner post 10 of the lower module, and finally the front corner post of the upper module being fitted on the central post 2 of the lower module, while a r 120 ° rotation of the upper module in the clockwise direction from the stack of FIG. 6 makes it possible to obtain the stack of FIG. 8, in which the central post 2 of the upper module is fitted on the corner post before 10 of the lower module, the front corner post 10 of the upper module is fitted on the rear corner post 11 of the lower module, and finally the rear corner post of the upper module is fitted on the central post 10 of the module lower (Figure 8). The assembly according to the invention of modular elements for producing a helical modular staircase according to the invention also comprises, in addition to modules 1 staircase with two steps 3, 4, at least one, and in general a plurality, railings as shown in FIG. 9.

This railing 18 comprises two uprights 19a and 19b tubular and parallel, vertical in position of use of the railing 18, of the same external and internal diameters, and therefore of the same thickness, for example of a thickness of 1.5. mm and an outer diameter of 30 mm, the largest 19a has a length of 1 905 mm and the smallest a length of 1 590 mm, the two uprights 19a and 19b being braced, in the lower part, by a cross member 20a perpendicular to the two uprights 19a and 19b, so horizontal in the use position, the two uprights 19a and 19b having their lower end in the same plane perpendicular to these amounts. In the upper part, the two uprights 19a and 19b are braced by two crosspieces 20b and 20c inclined parallel to each other, the upright 19a the longest down and the other 19b the shortest amount, the one of the crosspieces 20c connecting the upper ends of the two uprights 19a and 19b. The three crosspieces 20a, 20b, 20c are tubular, with the same dimensions of internal and external diameters and thickness as the amounts. At a slightly lower level than that of the lower rail 20a, each of the two uprights 19a and 19b supports, projecting outwardly, a cylindrical sleeve 21a, 21b of circular section, each obtained by cutting a section of 100 mm long in a tube for example of 60.3 mm external diameter and a thickness of 2.5 mm, each of the two sleeves 21a and 21b being connected by a plate 22a and 22b to the corresponding upright 19a or 19b; flat having for example a length of 38 mm and a thickness of 5 mm, the axes of the sleeves 21a and 21b being parallel to the uprights 19a and 19b. In the upper part, near its upper end, each of the two uprights 19a, 19b also supports outwardly projecting sidewardly, a pin 23b, 23b, parallel to the uprights and projecting upwards relative to a connecting plate from the lower end portion of each tenon to its respective amount.

As described below, in particular with reference to FIGS. 15c and following relating to the mounting of the staircase, each sleeve 21a, 21b is able to engage on the upper end of the rear corner post 11 of a module. 1 of stairs or on an angle post post, among those described below with reference to Figures 10 to 11c, while the tenons 23a and 23b are adapted to be housed in lateral sleeves of some of said post posts angle described below.

The railing 18 is made by assembling, for example by welding, its components which are all metallic, preferably of a metal or light alloy. The set of modular elements according to the invention also comprises other modular elements which are corner posts according to Figures 10 to 11c.

Among the plurality of corner post posts of the set of modular elements according to the invention, a first 24a, shown in FIG. 10, is a tubular rectilinear post, substantially of the same structure and dimensions as the post of front angle 10 of module 1 with two steps 3 and 4, and having a lower female end and a male upper end which are respectively compatible with the male upper end and the lower female end of the front corner post 10 of the module 1 , preferably in its variant according to Figure 4b, wherein the upper end cap 14 is a sleeve extended by about 150 mm compared to that of Figure 4a. There is therefore a tip 14 in the form of a steel sleeve, for example about 350 mm long, pierced with screw holes 16 in its projecting upper end above the tubular body 25a of the post 24a, alloy aluminum or aluminum, and which has the same height as the tubular body of front corner post 10, 400 mm for example, the tip 14 being retained by screwing or bolting 15 of its lower end portion in the tubular body 25a, whose lower end portion is integral with an external lateral projection fastener 26a on the tubular body 25a, and pierced with a hole 27a allowing a pivotable removable connection, about an axis perpendicular to the longitudinal axis of the pole 24a, with the free end of a hinge hinged at its other end to a second post of angle post 24b according to Figure 11a.

Finally, the tubular body 25a of the first corner post pole 24a comprises an annular flange 28a, which forms a circumferential stop protruding radially outwards, to limit the fitting of a sleeve such as 21a or 21b of a guard rail 18 on this first post 24a angle post.

The second post 24b of angle post comprises, like the first post 24a of angle post, a tubular body 25b, whose length is twice that of the first post 24a, so about 800 mm, the upper end of which male is equipped, in the same way, a tip 14 retained by screwing or bolting 15 in the tubular body 25b of the second pole 24b, which also has a lateral attachment 26b projecting in its middle part, and pierced with a hole 27b for a link articulated about an axis perpendicular to the longitudinal axis of the second pole 24b on a free end of a smooth 31c hinged to the third column post 24c of Figure 11b. The second post 24b of corner post also comprises an annular flange 28b, similar to the annular flange 28a of the first post 24a, but also comprises a smooth 29b hinged at one end about an axis 30b perpendicular to the axis second post 24b on the latter, and whose free end 31b is adapted to be articulated removably on the fastener 26a of the first post 24a.

Thus, the first and second stud posts 24a and 24b have the same structure and the same dimensions except that the second 24b is a double length of the first 24a, the clip 26b of the second pole 24b is substantially the same. mid-length, and not in its lower part as for the first pole 24a, and finally the second pole 24b further comprises the smooth 29b, tubular structure, articulated about the axis 30b of the tubular body 25b, substantially at level of the fastener 26b but on the opposite side of the body 25b, and whose free end 3 lb is adapted to be removably connected to the fastener 26a of the first stud post 24a angle.

FIG. 1 lb shows a third post 24c of angle post, the structure and dimensions of which are substantially the same as for the second posts post 24b, except that the length of the third post 24c is three times that of of the first post 24a, that its fastener 26c is at the same distance from the upper end of the end piece 14 as on the first and second posts 24a and 24b, so that the different elements and components of the third post 24c are located on FIG. 11b by identical references to those identifying the same elements or components in FIGS. 10 and 11a or assigned an index "c" to distinguish them from similar elements and components marked with references assigned an index "a" in Fig. 10 for the first post 24a and the index "b" for the post 24b of Fig. 11a.

FIG. 11c represents a fourth post 24d of angle post, whose elements and components identical or similar to those of the three posts previously described are marked by the same references assigned an index "d", the length of the fourth post 24d being quadruple that of the first pole 24a, and this fourth pole 24d having the particularity of comprising in addition, relative to the other three, two sleeves 32d, projecting laterally on either side of the tubular body 25d in its lower half and parallel to the axis of the tubular body 25d, these sleeves 32d being adapted to each receive a railing post, such as a post 23a or 23b of the guard rail 18 of Figure 9, as described below for the mounting of the staircase, and so that the smooth 29d of the fourth post of angle post 24d can function, when mounted in inclined spacer between two posts of angle post, safety rail s an addition to the two rails 20b and 20c of a railing 18 mounted on the staircase prior to the fourth stud post 24d considered, as described below. The set of modular elements for the construction of a staircase according to the invention further comprises a closing railing, as shown in FIG. 12, to prevent the passage beyond the high step of the last module. a staircase with two steps mounted at the upper end of the staircase, the exit of which then takes place laterally, over the slime of the latter module with two steps.

The closing railing 33 of FIG. 12 comprises two parallel rectilinear tubular posts 34 of the same length, vertical in the position of use of the railing 33, and such that their lower ends are in the same horizontal plane, the two 34 uprights being braced by three rectilinear smooth, tubular and perpendicular to the two uprights 34, and rigidly connected by each of their two ends to one respectively of the two uprights 34, a top rail 35 connecting the two upper ends of the two uprights 34, a middle rail 35 connecting the two uprights 34 substantially two-thirds of their height, and the third lower rail 35 connecting the two uprights substantially one-third of their height from their lower ends. The railing 33 thus has the shape of a rectangular frame open between the lower ends of the two uprights 34. In the middle part of the two uprights 34, between the two median and lower crosspieces, the railing 33 also comprises two sleeves 36 outwardly projecting sideward, each on one respectively of the two uprights 34, to which the sleeve 36 is connected by a plate 37 welded to the upright, the axes of the two sleeves 36 being parallel to the longitudinal axes of the two uprights 34. These Sleeves 36 are able to removably engage the central post 1 and rear corner 11 of the last module 1 two steps of the stairs. In the lower part of each of the two uprights 34, and outwardly projecting towards the rear, as the plates 37 supporting the sleeves 36, each upright 34 supports a collar 38, of the type with two pivoting jaws, one relative to each other about an axis substantially parallel to the axis of the corresponding upright 34, the two jaws can be closed against each other by screwing, so that the collar 38 is able to be removably mounted one around the central upright and the other around an angle upright of the staircase, or around a fourth stud post 24d mounted on a rear corner post 11 and in the extension vertical of the latter on a module 1 steps of the stairs. In addition, in the upper part of the two uprights 34 of this railing 33, two pins 39, projecting towards the upper end of the uprights 34, are each supported by one of the two uprights 34 projecting laterally outwardly. and towards the rear of the frame of the railing 33, these two pins 39 being able to be mounted in sleeves 32d of fourth posts 24d of angle post, at the end of assembly of the upper end portion of the 'staircase. The set of modular elements according to the invention further comprises, as represented in FIG. 14, two independent foot jacks 40, such as that of FIG. 13, as well as a substantially horizontal trapezoidal base 41, each of which the ends of the large base 42 as the small base 43 of the base 41, and the middle of the large base 42 are equipped with one respectively five foot jacks 40 analogous, the structure of a foot jack being shown schematically in FIG. 13. Each foot jack 40, of a well-known structure, comprises a ground support plate 44 supporting a vertical threaded rod 45 on which is screwed a wing nut 46, with a stopping point 48 on the rod 45 which limits upwardly the height adjustment range of the nut 46, on the fins 47 of which can bear the lower female ends of the front and rear corner posts 10 and 11 from module 1 to d their steps or the lower female ends of the first, second, third and fourth corner post columns 24a, 24b, 24c and 24d previously described, in order to compensate for a lack of flatness and / or horizontality of the ground surface where a staircase according to the invention must be mounted. On the base 41, the small base 43 and the two inclined sides 49, which connect the small base 43 to the large base 42, are each of the same length which corresponds to the length of one side of the hexagonal section of the staircase. The base 41 is made by assembling, for example by welding, rectilinear tubular sections which constitute, in this example, not only the two bases 42 and 43 and the two inclined sides 49 of the trapezoidal base 41, but also two spacers 50 each of which connects one respectively of the two ends of the small base 43 in the center of the large base 42.

The method of mounting a staircase is described below with reference to FIGS. 15a to 22.

The first three-step cycle is shown in Figures 15a, 15b and 15c. In the first step (FIG. 15a), a module 1 with two steps is mounted by its central post 2 on the foot jack 40 in the middle of the large base 42 of the horizontal base 41, and the two front corner posts. 10 and rear 11 of the module 1 are each mounted on one respectively of the two independent foot jacks 40, thereby defining the first of the six faces of the hexagonal horizontal cross-section staircase to be mounted. In the second step (FIG. 15b), the first post of corner post 24a is mounted vertically by fitting on the foot jack 40 at the end of the large base 42 of the base 41 towards which the module 1 of the The staircase rotates upward, and so that the first corner post post 24a delimits with the rear corner post 11 of the staircase module 1 the second face of the hexagonal staircase. In the third step of this first cycle, a railing 18 is mounted in this second face of the staircase by fitting one of its sleeves 21b on the upper male end of the rear corner post 11 of the module 1 , and by the other sleeve 21a on the male upper end of the first corner post pole 24a, as shown in Fig. 15c, which shows that the height of the male upper ends of the first corner post post 24a as of the rear corner post 11 of the step module 1 is greater than the height of the sleeves 21a and 21b of the railing 18, so that the upper end portions of the end pieces 14 (Figures 1, 4a and 4b) exceed above the sleeves 21a and 21b. In the first step of the second assembly cycle of the staircase, a second module 1 of steps is mounted by engaging its central post 2 on that of the first module 1 (see Figure 16a), its front corner post 10 on the part from the upper male end of the rear corner post 11 of the first module 1 which protrudes above the sleeve 21b of the railing 18, and its rear corner post 11 on the part of the upper male end of the first an angle post post 24a protruding above the other sleeve 21a of the railing 18. At the second stage of the second cycle, the second post of angle post 24b is fitted on the foot jack 40 to the end closest to the small base 43 of the base 41, and the articulated arm 29b of the second pole 24b is fixed in spacing between the second pole 24b and the first 24a by connection of the smooth 29b with the fastener 26a of the first corner post 24a, in the third ace of the hexagonal staircase. In the third step of this second cycle, a guard rail 18 is mounted in this third face of the staircase by fitting its sleeve 21b on the upper male end of the rear corner post 11 of the second module 1 of stairs and its second sleeve 21a on the upper male end of the second column post 24b angle (Figure 16c). In the first step of the third cycle (FIG. 17a), a third module 1 of steps is mounted by engaging its central post 2 on that of the second module 1, its front corner post 10 on the part of the upper male end of the rear corner post 11 of the second module 2 protruding above the sleeve 21b of the second railing 18, and its rear corner post 11 is fitted on the portion of the upper male end of the second post 24b upright angle protruding above the sleeve 21a of the second railing 18.

Thus, in the first step of the third cycle (FIG. 17a), the third module 1 of steps is mounted on the second as the second one on the first, by vertical stacking of its central post 2 on that of the second module 1 from its rear corner post 11 on the male upper end portion of the second post post 24b protruding above the sleeve 21a of the second railing 18, and the front corner post 10 on the part of the upper male end of the rear corner post 11 of the second module 1 which protrudes above the other sleeve 21b of the second railing 18. At the second stage of this third cycle (Figure 17b) , the third post of angle post 24c of FIG. 11b is mounted on the foot jack 40 at the other end of the small base 43 of the base 41, and the articulated arm 29c of this third post 24c of the post angle is mounted in spacer between the second and third in 24b and 24c of angle post by fixing its free end to the fastener 26b of the second post 24b angle post (see Figure 11a). In the third step of the third cycle (FIG. 17c), a third railing 18 is mounted in the fourth lateral face of the staircase delimited by the second and third studs 24b, 24c of the corner post, by fitting its sleeve. 21b on the male upper end of the rear corner post 11 of the third step module 1 and its other sleeve 21a on the male upper end of the third corner post pole 24c. In the first step of the fourth cycle (FIG. 18a), a fourth module 1 of steps is installed, as the third one was on the second, by fitting its central post 2 on that of the third module 1, and fitting of its rear corner post 11 on the part of the male upper end of the third post of stud 24c which protrudes above the sleeve 21a of the third guard rail 18 and fitting of its front corner post 10 on the part of the upper male end of the rear corner post 11 of the third module 1 which protrudes above the sleeve 21b of the third railing 18. At the second stage of this fourth cycle, a fourth post 24d of the amount of Angle according to Figure 11c is mounted on the foot jack 40 at the second end of the large base 42 of the base 41, and its articulated arm 29d is mounted inclined spacer between the two posts 24c and 24d angle post delineating this nquième side side of the staircase, by fixing the free end 31d (see Figure 1) of this smooth 29d on the attachment 26c of the third post 24c angle post. This fourth cycle ends, in the third step, by mounting a fourth railing 18 (see Figure 18c), the sleeve 21a is fitted on the upper male end of the fourth post 24d angle post and of which the other sleeve 21b is fitted on the male upper end of the rear corner post 11 of the fourth step module 1.

The three stages of the fifth cycle are shown in Figures 19a, 19b and 19c. In the first step, a fifth module 1 of steps is mounted as the previous, by fitting its central post 2 in the vertical extension of those of the other modules 1 to form the central amount of the staircase, and by fitting its pole rear corner 11 on the portion of the upper male end of the fourth stud post 24d protruding above the sleeve 21a of the last guard rail 18 mounted, and fitting the front corner post 10 of the fifth module 1 on the male upper end portion of the rear corner post 11 of the fourth module 1 which protrudes above the second sleeve 21b of the fourth railing 18. At the second stage of the fifth cycle, another fourth post 24d of corner post is mounted on and in the vertical extension of the front corner post 10 of the first module 1 of the staircase, and its articulated rail 29d is attached to the clip 26d of the post angle post post cedemment mounted, namely a first fourth pole 24d. Indeed, from the corner post post 24d mounted in the second stage of the fourth cycle, all the corner post posts that are used are identical to the fourth corner post post 24d according to Figure 11c. In the third step of this fifth cycle, a fifth railing 18 is installed, like the previous ones, by fitting one of its sleeves 21a on the upper male end of the last post 24d of corner post mounted on the second step of this cycle, and fitting of the other sleeve 21b on the rear corner post 11 of the fifth module 1 mounted in the first step of this same cycle. The fifth railing 18 is thus disposed in the sixth face of the hexagonal staircase, above an entrance opening giving access to the base of the staircase, between the two posts 24d of corner post and below the smooth 29d inclined spacer between these two posts 24d.

The first step of the sixth cycle is to mount a sixth module 1 of steps, like the previous ones, and which is placed above the entrance of the staircase, which then comprises a complete turn (see Figure 20a). The central post 2 of this sixth module 1 is fitted in the vertical extension of the central posts 2 of the five previously mounted modules 1, and its front corner posts 10 and 11 rear respectively take on the parts that protrude above the Sleeves 21b and 21a of the fifth railing 18 of the rear corner post 11 of the previous module 1 and the last column post 24d installed. The second step of the sixth cycle (see FIG. 20b) consists in mounting a new post 24d of same angle post to the fourth post of FIG. 11c on the front corner post 10 of the second module 1 installed, and in fixing the rail 29d of the last pole 24d and inclined smooth rise bracing the last two poles 24d installed. In addition, one of the sleeves 32d of the last post 24d installed is engaged on the post 23b of the short amount 19b of the first railing 18 (Figure 9) installed in the third stage of the first cycle. In the third step of this sixth cycle, as at the end of each previous cycle, a sixth railing 18 is mounted (see Figure 20c) by fitting its sleeve 21a on the corner post post 24d which comes from be installed and fitting the other sleeve 21b on the rear corner post 11 of the step module 1 installed in the first step of this same cycle.

After the sixth cycle and up to the tenth, possibly even to the eleventh, each cycle is a repetition of the sixth cycle, with a level shift corresponding to the module 1 of steps added at each cycle, to achieve a second round of the staircase, plumbed above the first tower, the new corner post posts incorporated in the assembly being all identical to the fourth post 24d of Figure 11c. The first step of each of these cycles always concerns the installation of an additional module 1 of steps, the second step concerns the installation of a fourth post 24d of additional corner post, and the last step of each cycle always corresponds to the installation of an additional railing 18, except at the third stage of the eleventh cycle, to allow the exit of the staircase at the level of the twelfth and last module 1 of steps, in this example, where the spiral staircase is limited to two turns.

In these mounting cycles, starting from the fifth cycle, not only all the corner post posts mounted in the second step of each cycle are identical to the fourth post of corner post 24d, but each of them is mounted on a front corner post 10 of an underlying stair module 1, and in the vertical extension of the front corner post 10 of this module 1.

In addition, starting from the seventh assembly cycle, the two lateral sleeves 32d of each post 24d of angle post are engaged on the vertical studs 23a and 23b projecting laterally from two adjacent and underlying guard rails 18, previously mounted. Likewise, starting from the seventh assembly cycle, the rail 29d of each post 24d of the corner post is fixed by its free end 31d to the post column post 24d previously mounted in inclined spacer substantially parallel to the two inclined rails 20b and 20c of a guard rail 18 previously mounted and underlying, thereby acting as third inclined smooth, reinforcing the safety for users in the second tower of the stairs.

These last characteristics are visible in FIG. 21, which represents the second step of the tenth cycle, during which a new post 24d is mounted on the front corner post 10 of the sixth module 1, and its fixed sill 29d inclined on the post 24d previously mounted, after the installation of the tenth module 1 steps, mounted so that its rear corner post 11 is fitted on the upper end of a post 24d angle post whose two sleeves 32d are fitted one on the post 23a of the railing 18 previously mounted and below that which borders the tenth module 1 steps, while the other sleeve 32d of the corner post post 24d is fitted on the post 23b d a railing 18 previously mounted just after the guard 18 having the other post 23a, these two railings 18 underlying being adjacent by their studs 23a and 23b.

It will be recalled that, during the first step of a new assembly cycle, the front corner post 10 of a module 1 of steps is mounted on the rear corner post 11 of the module 1 mounted in the first stage of the previous cycle, with interposition of a lateral sleeve 21b of the railing 18 mounted in the third step of the previous cycle on the rear corner post 11. From the unfinished staircase of Figure 21, it reaches the completed staircase of Figure 22 by mounting a tenth and last railing 18 shown in Figure 22, mounted in the same manner as the others, in the third step of the tenth cycle, which then allows the assembly in safety of an eleventh module 1, in the first step of the eleventh cycle, and then mounting a new post 24d angle post for direct mounting of the twelfth and last module 1 steps, without the prior editing of another bodyguard. Thus, the front corner posts 10 and rear 11 of the last module 1 are fitted directly and respectively on the rear corner post 11 of the eleventh module 1 and on the new post 24d angle post, without interposition of sleeves. bodyguard. The closing railing 33 of FIG. 12 is mounted behind the top step 4 of the last module 1 and along the rear edge of this upstand 4, and fitted by its sleeves 37 on the upper ends of the central columns 2 and 2. rear angle 11 of the last module 1, and retained by one of its collars 38 around the central post 2 of the penultimate module 1 and the other collar 38 around the post 24d post amount supporting the rear corner post 11 of the last module 1.

In addition, the studs 39 of the closure railing 33 are engaged in sleeves 32d of two stud posts 24d mounted along the sides of the closing railing 33 and fitted on the upper ends of the central posts 2 and rear angle 11 of the last module 1. In addition, four other uprights 24d angle post are mounted vertically along the sides of the last three railings 18 and between them, by fitting on the upper male ends of the front corner posts 10 and 11 rear eleventh, tenth and ninth modules 1, the smooth 29d of these four posts 24d being fixed inclined between these posts 24d, to secure the access of the stairs to the last three modules 1 of steps, and the posts 23a and 23b of the railings 18 are engaged in sleeves 32d of these posts 24d to stiffen the upper part of the lateral exit staircase over the slime 7 of the last module 1 steps .

Claims (16)

1. Stair module (1) for a modular hexagonal spiral staircase of hexagonal horizontal cross-section, delimited by six vertical corner uprights around a vertical central upright, said module (1) comprising a central pole (2) of substantially vertical axis (Z) and two steps (3, 4) of substantially triangular shape, including a low step (3) and a high step (4), extending in horizontal planes perpendicular to the axis (Z) of the central post (2) and radially from said central post (2), to which the steps (3, 4) are each secured by a narrow edge (5) of radial inner end, characterized in that said two steps (3, 4 ) are each secured by a wide edge (6) of radial outer end to a single stringer (7) in the form of a substantially flat plate and parallel to the axis (Z) of the central post (2), the stringer (7) having a lower part (8) and an upper part (9) secured to the edge of the broad edge (6) respectively of the low step (3) and the high step (4), and in that the module comprises two corner posts (10, 11) with axes parallel to the axis (Z) of the post central (2), so that the lower ends of the three posts (2, 10, 11) of the module are in a transverse plane perpendicular to the axes of the three posts (2, 10, 11) of the module, and one of which two corner posts, said front corner post (10), is integral with the lower part (8) of the stringer (7) at the front end of the latter, the nose (12) of the low step (3). ) at its outer radial end, and the wide edge (6) of the lower step (3), at its front end, and the other corner post, said rear corner post (11) is integral with the upper part (9) of the silt (7) at the rear end of the latter, the rear edge (13) of the high step (4) at its outer radial end, and the wide edge (6) of the high step ( 4) at its rear end, the center post (2) and the two corner posts (10, 11) of the module (1) each having a female end and a male end which are respectively adapted to receive a male end and to be received in a female end of similar modules posts (1) identical to two steps, so as to contribute with said posts similar to the constitution of said central amount and said corner posts of the staircase. Stair module (1) according to claim 1, characterized in that the central post (2) and the two corner posts (10, 11) are three tubular posts identical to one another, joined together two steps (3, 4) and the common stringer (5), and whose upper ends are each extended by one respectively three male tips (14), each in the form of a sleeve, retained partially fitted in a corresponding pole and partially projecting above said pole (2, 10, 11), male upper end of said corresponding pole. Stair module (1) according to claim 2, characterized in that the three posts (2, 10, 11) of said module are made of metal or light alloy and secured at least by step welding (3, 4) and with the silt (5) which are in the same metal or alloy, each of the three male end pieces (14) being a steel sleeve retained, by its lower end portion, at least by screwing (15) into a corresponding post, and having a protruding upper end portion, above said corresponding post, and preferably drilled with radial screw holes (16), the lower end portion of each post (2, 10, 11) being also pierced with at least one radial screw hole (17). Stair module (1) according to claim 3, characterized in that the male end (14) of the front corner post (10) protrudes above the upper end of the corresponding post on a further high that the male ends (14) of the rear corner post (11) and the central post (2), which are identical and project from the same height above the corresponding posts. 5. Module according to any one of claims 1 to 4, characterized in that the stringer (7) has a substantially rectangular bottom portion (8) with lower and upper edges substantially parallel to the low step (3), and a portion high (9) substantially U-shaped returned, upper edge substantially parallel to the high step (4). 6. Module (1) according to any one of claims 1 to 5, characterized in that the parallel axes of the three posts (2, 10, 11) of the module each pass through one respectively of the three vertices of a triangle. equilateral in a transverse sectional plane of the module (1) perpendicular to the axes of said posts (2, 10, 11), and each step (3, 4) has a substantially rectangular plan shape. 7. Set of modular elements, for making a modular helical staircase hexagonal horizontal cross section delimited by six vertical corner uprights around a vertical central upright, characterized in that at least one modular element among said modular elements of the assembly is a module (1) staircase with two steps (3, 4) according to any one of the preceding claims, at least a second modular element among the modular elements of the assembly being a railing (18). ) comprising two vertical tubular uprights (19a, 19b) of unequal length, braced, in the lower part, by a horizontal crossmember (20a) and in the upper part by at least one, but preferably two, crossing (s) (20b, 20c ) inclined (s) forming smooth (s) of protection, each of the two rails (19a, 19b) railing supporting, projecting outwardly, a sleeve (21a, 21b) at the bottom and a pin ( 23a, 23b) projecting upwards in the upper part, which are parallel to the railing upright (19a, 19b), said sleeve (21b, 21a) being able to engage on the upper end of the rear corner post (11) d a staircase module (1) or on an angle post post (24a, 24b, 24c, 24d) constituting another modular element of said assembly, said tenons (23a, 23b) being able to be housed in lateral corner post sleeves (32d) (24d) of the assembly. 8. Set of modular elements according to claim 7, characterized in that it further comprises a plurality of corner post columns comprising: a first post (24a) of substantially the same structure and dimensions as the post of front angle (10) of the staircase module (1) with two steps, and having female and male ends respectively compatible with the male and female ends of said posts (2, 10, 11) of said module (1), but with, in addition, an annular collar (28a) forming an abutment limiting the fitting of a railing sleeve (21a, 21b) on said first post (24a), and an external lateral projecting fastener (26a), adapted for a detachable connection with a free end (31b) of a rail (29b) hinged at its other end to a second post (24b) of angle post, said second post (24b) being substantially of the same structure as the first post (24a) of corner post, but of a height twice that of said post first post post (24a), a third post (23c), of substantially the same structure as the first post (24a) of corner post but of triple height of that of said post post (24a) of post angle, and at least one fourth pole (24d), also substantially of the same structure as the first post of angle post (24a), but four times the height of said first post post (24a), second (24b), third (24c) and fourth (24d) post posts having in addition a rectilinear rail (29b, 29c, 29d) articulated by a pivot end about a horizontal axis (30b, 30c , 30d) on said post post (24b, 24c, 24d) substantially to the length of the first post post (24a) from the top end of said post (24b, 24c, 24d), and adapted to be removably connected by its other end (31b, 31c, 31d), in inclined strut, to said fastener (26a, 26b, 26c, 26d) of a neighboring corner stud post delimiting the same face of the hexagonal staircase, and said at least one fourth post (24d) of corner post having further, projecting sideways on either side a portion of said post (24d) in its lower half, two sleeves (32d), parallel to said fourth post (24d), and each adapted to receive a post (23a, 23b) guardrail (18), so said sloping spacer bar (29d) of a fourth post of angle post (24d) is adapted to act as an additional safety rail added to the at least one smooth rail (29a, 29b) inclined by a railing (18) previously mounted on the stairs. 9. Set of modular elements according to claim 7 or 8, characterized in that it also comprises an additional modular element arranged in railing (33) for closing the staircase, comprising two uprights (34) of guard- tubular bodies, rectilinear, parallel and of the same height, braced by at least two straight (35) rectilinear horizontal, rigidly connected, by each of their two ends, to one respectively of the two amounts (34) of guardrails (33 ), including an upper rail (35) connecting the two upper ends of the two rails (34) railing, and at least one rail (35) median or lower, so as to form a rectangular frame open between the lower ends of these two uprights (34), said guard rail (33) also comprising, in the lower part of the uprights (34) and outwardly projecting outwardly, two collars (38) each connected to one of the two uprights (34), and apt to be removably mounted one around the central upright and the other around a corner upright of the staircase, in the middle portion of the uprights (34) and projecting outwardly lateral, two sleeves (36) each bound to one of the two uprights (34) and of axis parallel to the latter, and adapted to be mounted removably on the central columns (2) and rear angle (11) of a last stair module of said assembly, and, preferably, in the upper part of the two uprights (34) of the railing (33) closing, two pins (39) projecting upwards and adapted to be mounted in sleeves (32d) of poles (24d) corner post of said modular assembly. 10. Set of modular elements according to any one of claims 7 to 9, characterized in that it also comprises, as additional modular elements, two foot jacks (40) independent, each of which is able to adjust in height l one respectively of the two corner posts (10, 11) of a first module (1) staircase with two steps, and a base (41) trapezoidal substantially horizontal, including the small base (43) and the two inclined sides (49) are of the same length corresponding to one side of the hexagonal section of the staircase, and produced by the assembly of rectilinear tubular sections constituting at least the two bases (42, 43) and the two sides inclined (49) of the base (41) trapezoidal, which is equipped with a foot cylinder (40) at each of its four vertices, and adapted to adjust the height of the poles (24a, 24b, 24c, 24d) of corner post delimiting three adjacent faces of the horizontal cross-section hexagonal of the helical modular staircase, a fifth foot cylinder (40) equipping the middle of the large base (42) of the trapezoidal base (41) for the height adjustment of the central pole (2) of said first module (1). ) staircase with two steps. 11. Modular helical staircase of hexagonal horizontal cross-section, delimited by six vertical uprights around a vertical central upright, characterized in that it comprises a set of modular elements according to any one of claims 7 to 10. . 12. A method of mounting a helical modular staircase according to claim 11, characterized in that it comprises a succession of cycles each comprising three stages, the first of which is the arrangement of a module (1) staircase two steps on the ground or on an identical module (1) and a post (24a, 24b, 24c, 24d) of previously arranged angle post, and such that the two corner posts (10, 11) of said module (1 ) of stairs define a face of the hexagonal horizontal cross-section staircase, the second step of which is the disposition of a post (24a, 24b, 24c, 24d) of corner post, on the floor or on another module (1) identical arranged beforehand, so that said stud post (24a, 24b, 24c, 24d) delimits with the rear corner post (11) of said module (1) staircase an adjacent face of the hexagonal staircase, and whose third step is to mount a railing (18), fitted by one (21a) of s two lower part sleeves on said post post (24a, 24b, 24c, 24d) and the other (21b) of the two sleeves on said rear corner post (11) of said module (1) d staircase, so that the railing (18) extends into said adjacent face of the hexagonal staircase. 13. A method of mounting a helical modular staircase according to claim 12, characterized in that the first cycle consists in mounting, in its first step, a first module (1) of stairs by each of its corner posts ( 10, 11) on one respectively of two independent foot cylinders (40), defining a first lateral face of the hexagonal staircase, and by its central post (2) on a foot jack (40) mounted in the middle of the large base (42) of a trapezoidal base (41) according to claim 10, then, in its second step, mounting a first post of angle post (24a) on the foot jack (40) mounted on the end of the large base (42) of the base (41) in the direction of rotation of the staircase, then, in its third step, to mount a first guardrail (18) by its sleeves (21a, 21b) on the rear corner post (11) of said first stair module (1) and on said first post of the corner post (24a), which defines ssent a second side face of the hexagonal staircase, then to reproduce a second cycle, consisting, in its first step, to mount a second module (1) of stairs on the first, by mounting the front corner post (10) ) of the second module (1) on the rear corner post (11) of the first module (1), the central post (2) of the second module (1) on and in the extension of the central post (2) of the first module (1), and the rear corner post (11) of the second module (1) on the first corner post post (24a), then, in its second stage, to mount a second post post (24b) angle, of double height of that of the first stud post (24a), on a foot cylinder (40) mounted on the top of the small base (43) of the trapezoidal base (41) which is closest to the first post (24a) of the corner post, and to connect the free end (31b) of its rail (29b) to said first posts post (24a), so as to stiffen er assembly and define, by said first and second stud posts (24a, 24b) angle post, a third side face of the hexagonal staircase, and then, in its third step, to mount a second guardrail ( 18) in this third side face of the staircase, by engaging one (21a) of the sleeves of said second guard (18) on the second post (24b) of the corner post and the other sleeve (21b). on the rear corner post (11) of the second module (1), then to reproduce a third cycle, the first step of which consists in mounting a third stair module (1) by mounting its front corner post (10). ) on the rear corner post (11) of the second module (1), its central post (2) on and in the extension of the central post (2) of the second module (1), and its rear corner post (1); 11) on the second post (24b) angle post, then, in its second step, to mount a third post (24c) corner post, high r equal to three times the height of the first corner post post (24a), on a foot jack (40) mounted on the other vertex of the small base (43) of the trapezoidal base (41), and to connect the free end (31c) of its rail (29c) to said second stud post (24b) angle so as to stiffen the assembly and delimit a fourth side face of the hexagonal staircase by said second and third posts (24b, 24c) of angle post, and to complete this third cycle by its third step, by mounting a third guardrail (18), one of which (21a) sleeves is fitted on the upper end of the third post (24c) of the corner post, and the other post (21b) on the rear corner post (11) of the third stair module (1), then to complete a fourth cycle, the first of which step consists in mounting a fourth stair module (1) by mounting its front corner post (10) on the rear corner post (11) of the third me module (1), its central post (2) on and in line with that of the third module (1), and its rear corner post (11) on the upper end of the third column post (24c) angle, then, in its second step, to mount a fourth post (24d) of corner post, a height which is four times that of the first corner post post (24a), on a foot jack (40) mounted on the second vertex of the large base (42) of the trapezoidal base (41), and connecting its rail (29d) to the third post (24c) of the angle post, so as to stiffen the assembly and delimit a fifth face of the hexagonal staircase, and to complete this fourth cycle by its third step, by mounting a fourth guardrail (18), a sleeve (21a) is fitted on the upper end of the fourth pole (24d) of the corner post, and the other sleeve (21b) is fitted on the rear corner post (11) of the third module (1), and thus e continued until reaching the desired height of the staircase, each tower of which is constituted by the assembly of six modules (1) of stairs with two consecutive steps, the use of six columns of angle post and six railing (18). 14. A method of mounting a modular staircase according to claim 13, characterized in that from the fifth cycle, all corner post columns mounted in the second stage of the cycles are identical to the fourth pole (24d) of corner post, and each corner post post (24d) is mounted on and in extension of a front corner post (10) of an underlying stair module (1). 15. A method of mounting a modular staircase according to any one of claims 12 to 14, characterized in that from the seventh cycle, the two sleeves (32d) side of each post (24d) angle post are engaged on the vertical projections (23a, 23b) in lateral projection of two adjacent pre-mounted adjacent railings (18). 16. A method of mounting a modular staircase according to any one of claims 12 to 15, characterized in that from the seventh cycle, the smooth (29d) of each pole post (24d) corner post is fixed by its free end (3 ld) on the post (24d) of angle post previously mounted inclined spacer substantially parallel to the or inclined (s) (s) (s) (29b, 29c) of a railing ( 18) previously mounted, so as to act as third inclined smooth.