FR2519051A1 - Spiral staircase for building - comprises wooden steps secured to helical beam by threaded bolts - Google Patents

Abstract

The spiral staircase comprises a helical beam (1) containing a cable (8) which is placed under tension by anchor (2) at its ends. All the steps (3), except for the top (5) and bottom (4) steps, are identical and interengage with vertical spacers (6). The steps are held in position by threaded bolts which screw into the spiral beam (1). The steps (3) are made of hard wood.

Description

 The subject of the present invention is the production of hardwood stairs with debilitated stringers, fixed at the foot and at the head.

 New industrial products, manufactured, according to the most appropriate dimensions, and the details indicated.

The mounting system is of the "mechanical" type (parts that fit together or bond to each other). The connection and fixing are: ensured by tensioned threaded rods, in high-strength steel, like "Dywidag bars"
For the stringers, use 4th monotoron cables, tensioned by cylinders.

 Devices for interventions of subsequent tensions will be provided.

 These staircases manufactured in series, according to different models, will adapt to all styles of interior architecture, and will bring a refined decorative note. They will mainly be made of wood, a raw material that is renewed, and often abundant in many regions. A beautiful appearance, warm to the touch. With great heat and sound insulation, attenuating vibrations, which can be treated for a long time, and fireproof. Adds equal.

ment, the qualities of mechanical resistance of the filtered rods and the tensioned connecting cables, which bring to the whole, both rigidity and flexibility
To size the pieces of wood or steel, he will perform PDX calculations according to the constraints to be cashed. The characteristics of basic materials both: For wood, a linear average expansion, and a perpendicular average expansion, a coeficient of resistance and a densi
For steel, the average expansion in all directions, its coeficient to resist its relaxation over time (hence the possibility of intervening at certain points to restore rigidity to the structure), and its density.

 The steps will be embedded in the stringers, it can be substituted in some cases, below each of them, a wooden or metal square, embedded and aimed, acting as a decorative motif.

 These prefabricated staircases, made up of manageable elements linked to each other, will be remarkable, as for the possibilities of hanging on them if necessary, decorative or construction panels, and small pipes.

 A performance to be noted is the ease and speed of implementation, common on the one hand, to the standardized system, and on the other hand, to the mounting and fixing devices.

 A very large model gambit can be studied, with only a few basic models. Different curves can succeed straight lines.

 We can of course, consider stairs with one or two stringers with the same characteristics, to support the steps.

The railing balusters can be made of wood or metal, and of different: shapes, they will be integral with the stringers and steps, (linked by the same
fixing $.

 The ends of the threaded rods or cables will be arranged so as to allow easy access, necessary for their tension.

 Reinforcing metal plates are judiciously fixed at the places where it is needed, to avoid splitting of the wood.

Drawing of Plate I
I1 represents a staircase module with a single stringer, plan view with the arrow I / 20. in no way limitative standard of execution. We see in (I) the stringer stranded, with its fixing anchors and tension at the ends, (2).

 (3) Indicates that the thirteen identical balanced steps, for this model, only the starting step (4) and the landing step (5) are different.

 In (6) we distinguish the counter-steps, and in (7) the threaded rods connecting to the stringer, with the tensioning devices.

 (8) Represents the single-stranded assembly cable, of the eight parts of the stringer, six of which are identical. The cable is fitted with a tension system near the fixing anchors, visible in (2).

 We recognize in (9), the upper support piece on which the staircase is fixed.

Drawing of Plate II
Figure I is the elevation of the stair stringer, seen along section AA! ..

from the drawing of plate I. We see in (1) the initial volute, in (2) which steps are drawn by transparent, and in (3), the vertical cross section of the stringer, with the hole in the cable.

 Figure 2 shows the view B.B'. Of the drawing of plate I.

 We see in (I) the end steps, in (2) the steps with their grooved assemblies. (3) indicates the external part of the threaded rod, fixing to the stringer.

 FIG. 3 represents an example of a square for maintaining the arch, to avoid embedding in the stringer.

 Figure 4 shows an elevation of a different model from that of plate I. It has two stringer struts to support the steps.

 All special features of the central stringer apply to the exterior linon.

Claims (1)

 9. E V E l D I C A T I O N S  IO- These hardwood stairs preferably, with stringed stringers, made in several parts, and with balanced steps. Are characterized, on the one hand, by the prefabrication of manageable elements, according to standardization rules. On the other hand, by their connection and assembly devices, appozed by high resistance threaded rods, and tensioned cables.  20- These hardwood stairs according to claim 1. Are pre-calculated to withstand the necessary stresses. the threaded rods, or cables (possibly stretched by cylinders) can be, as required, either free in the wood, or surrounded by metal sheaths. The whole can be, partially or totally secured by synthetic resins.  30- These hardwood stairs, according to claim 1, is characterized in that, each element, is easily assembled by joining or fitting perfectly together, so as to form a rigid assembly at the end of the operation. and harmonious. They can thus be dismantled and reassembled like a piece of furniture, to be changed places.  40- These hardwood stairs, according to claim 1, is also characterized in that the ends of the threaded rods are placed in places to integrate diacretely into the assembly. They can be inserted into the railing baluster feet. Appropriate devices allow a later tension, to restore rigidity to the structure. 59- These hard wooden staircases, according to claim 1, are further characterized by metal reinforcing plates, judiciously placed at the necessary places, to avoid the splitting of wood due to cable tension.  60- These hardwood stairs, according to claim 10, au.ront steps, either embedded in the stringers, or supported below, by small wooden or metal brackets.