Modular space structuration device

The present invention relates to a modular space structuration device enabling open or closed spaces to be rapidly arranged for accommodating a large number of persons. Modules comprise a platform provided with seats and supported by compasses, each leg of the compasses being pivoted at its lower part on telescopic strut members of variable length, themselves pivoted at their upper end on said platform. One application of the present invention is the temporary installation of grandstands, theatres, tiers, amphitheatres etc.

The present invention relates to a modular device intended particularly but 
not exclusively for rapidly arranging enclosed or open spaces where a 
certain number of persons will be assembled for public meetings, 
theatrical performances or the like. 
In a known device, a platform, provided with independent lifting means 
carried by a member in the form of compasses, is characterised in that the 
fulcrum of the lifting forces of said platform is very close to its centre 
of gravity, so that it rises or descends in balanced position on a pivot. 
This particularity is advantageous insofar as the placing into work 
position may be effected by hand when the platform has been raised, this 
position being ensured by means added at that moment and which consist of 
chains and struts. However, apart from the necessity of resorting to 
supplementary means which may sometimes raise problems of maintenance, the 
forces to be applied to the raising of the platform, at the moment when it 
passes from low to high position by closure of the compasses, are very 
considerable, this leading to the use of over-sized lifting means or to 
the platform, in folded position, being of relatively great height. The 
direction of application of the lifting or raising forces of the platform 
is such that the compasses cannot be completely open, this being 
translated by a sometimes inacceptable bulk. Now, the height of the folded 
platform is an important element in the choice of the consumers. Moreover, 
the raising of a platform of one to two tons in equilibrium may raise 
problems of safety. 
The present invention has for its object a platform overcoming the 
above-mentioned drawbacks, whilst conserving the advantages of the known 
device. 
In accordance with the present invention, the platform mounted on supports 
forming compasses, themselves pivoted near the centre of gravity of said 
platform, is characterised in that each leg of said compasses is pivoted 
at its lower part on telescopic strut members of variable length, 
themselves pivoted at their upper end on said platform. 
The length of the struts is advantageously controlled by one or more jacks, 
preferably screw jacks. 
The device for lifting the platform is thus constituted by two deformable 
triangles and the self-stabilised platform has no need of supplementary 
bracing members. 
Whilst the compasses are pivoted below the platform, the struts are 
advantageously pivoted on the upper part thereof, so that when the legs of 
the compasses form an angle of 180.degree., the struts form with the 
surface of the platform an angle of a few degrees allowing it to be raised 
.

Referring now to the drawings, FIG. 1 shows the platform according to the 
invention which comprises a rectangular frame 1, constituted by two 
supports 2, only one of which is visible in the Figure, connected by at 
least two cross-pieces (not shown). The supports 2 bear containers or tubs 
3 perpendicular thereto. The tubs are of truncated, hemicylindrical 
section, and their upper surfaces 4 are substantially contiguous, so that, 
in rest position, they form a continuous flat surface, and, in working 
position, a succession of tiers 4 separated by the side walls 5 of the 
tubs 3 (cf. FIG. 4). 
The tubs 3 may contain seats 6 which may be arranged on the tiers by 
pivoting the upper surface thereof about a median axis. The folded 
position of a seat is shown at 7 in FIG. 1. 
The frame or support frame 1 is borne by two compasses 8, only one of which 
has been shown, in broken lines, in FIG. 1, said compasses 8 comprising 
two legs 81 and 82 pivoted on a fork joint 10. Each leg of the compasses 
virtually forms part of a compass frame. In FIG. 1, the compasses are 
completely open. The free ends 83 and 84 of the legs are mounted on wheels 
9 which enable the compasses 8 to open and close. On the spindles of the 
wheels are pivoted the lower ends of the struts 11 and 12. There are two 
pairs of struts, but only one has been shown in the Figure, in broken 
lines. As for the compasses, each strut is part of a strut frame 
comprising two struts connected by cross-pieces. Strut 11 is pivoted at 83 
on the one hand and, on the other hand, at 15 on the support. The strut 11 
is, in practice, constituted by a section 18 of fixed length inside which 
is housed a screw 19 which constitutes the section of variable length of 
the strut. The length of the variable section is controlled by a screw 
jack 13. In the same way, the strut 12, pivoted at 84, is also pivoted at 
16 on the support. It is composed of a section 20 of fixed length and of a 
screw 21 partially penetrating said section 20, under the influence of 
jack 14. A railing 17 has been shown which is fixed in conventional manner 
on the edges of the tiers, for safety purposes. 
From the low position shown in FIG. 1, the process of raising the platform 
is clearly visible in FIG. 2. The screw jacks 13 and 14 are driven by a 
rotary movement of the motors (not shown in the Figure) so that the screws 
19 and 21 extend out of sections 18 and 20 respectively. The length of the 
struts 11 and 12 increases, this causing the platform to rise and the 
compasses close. The lifting means are therefore not carried by the 
compasses but by the struts. The thrust force is made by the jacks of the 
struts and the legs of the compasses now work only in traction, when the 
platform is being raised. 
The legs of the compasses consequently play an essential role in the 
necessary rigidity when used for ensuring stability of the platform. It 
will be noted that, contrary to what exists in conventional hoisting 
systems, which employ a fixed ground support, the ground support is 
obtained, according to the invention, by wheels which participate in the 
raising and lowering of the platform. 
The jacks being identical, the platform rises into horizontal position if 
the drive speed of the motors is the same on each side. To obtain the 
inclined position shown in FIG. 3, it suffices either to control only the 
left-hand jacks, starting from the position of FIG. 1, or to actuate the 
right-hand jacks, starting from FIG. 3. 
FIG. 4 shows the platform in an intermediate position, the tiers having 
been brought into position of use. 
FIG. 5 shows more clearly the structure of the lifting device, which is 
perfectly symmetrical, the different parts having identical references. 
The motor 22 for driving the jacks, shown schematically, is disposed in 
the centre of the struts which are connected by cross-pieces 23. The motor 
22 rotates, via a bevel gear 24, the jacks 14 which cause the screws 21 to 
rise or descend outside or inside the cylinders 12. The motor 22 is fixed 
to the frame 12, 23 by any suitable means. 
Preferably, the struts are pivoted at their upper part on the platform 
symmetrically with respect to the centre of gravity thereof, the two 
pivots being distant from each other by about 1/3 of the length of the 
platform. Furthermore, the length of the legs of the compasses may be 
substantially equal to one half of the length of the platform.