EP0094297A1 - Hanging scaffold movable with respect to a structure, and method of moving such a scaffold - Google Patents

Abstract

The hanging scaffold has four suspension cables (31, 32, 33, 34) associated with motors (21, 22, 23, 24), and additional retaining means such as two poles (41, 42) to permit the hanging scaffold to advance between the tie-beams (11, 12, 13, 14). Used in the painting of metal frames. <IMAGE>

Description

The invention relates to a nacelle movable relative to a structure and in particular a system for horizontal displacement in two perpendicular, transverse and longitudinal directions, of a suspended nacelle, for cleaning and / or painting of a frame, in particular metallic.

To clean and / or paint a frame, in particular a factory or warehouse metal frame, a rolling scaffold is generally used which is moved on the ground over the entire surface of the building, in order to allow the treatment of all parts of the frame. Such a system makes it imperative to completely free up the floor space of the building on which the scaffolding moves, in particular for buildings in service, which requires manpower, leads to loss of time, and therefore of money. , both for the personnel treating the frame and for the owner of the building, without taking into account the drawbacks that result for the latter.

We know, moreover, that there is a material allowing the repair and / or the treatment of the vertical facades of very tall buildings. This material essentially consists of a nacelle suspended via cables on an upper rail, with means allowing its displacement vertically by the clearance of the cables, and horizontally thanks to the upper rail, in the vertical plane of the facade to be treated. .

A frame, and in particular a metal frame, generally consists of trusses resting on pillars, the lower part of each truss being constituted by a bar or purlins arranged horizontally, the struts or purlins being parallel and at a distance n the one from the other in the direction of alignment of the trusses, or transverse direction x of the frame.

In order to avoid the drawbacks entailed by the use of scaffolding for cleaning and / or painting of frames, in particular metal, the invention proposes to use a suspended nacelle, with simple and reliable horizontal movement system in two perpendicular directions, one transverse.x confused with the direction of alignment of the trusses, the other longitudinal confused there with the direction in which is placed (e) each entry or breakdown.

As is known, the nacelle essentially consists of a rectangular platform with railings and peripheral protective mesh.

More precisely, the invention relates to a nacelle movable relative to a structure comprising substantially parallel ties or the like, for example a frame, characterized in that said nacelle comprises four cables of variable length provided at their ends with means for hooking to said ties and connected at four points on the platform defining a quadrilateral and additional retaining means, of given length, capable of being fixed in a removable manner between said nacelle and a chosen point of said structure.

The aforementioned additional retaining means will preferably be constituted by two rigid poles, each pole end being provided with hooking means. Thus the poles can be easily hung on neighboring ties, while they will be fixed at their lower ends to anchor points provided on the nacelle. Furthermore, each cable is preferably terminated by a rigid part defining the hook by which it can be fixed to the ties and this rigid part is provided long enough so that it can easily be grasped from the nacelle and hung or unhooked from the ties.

• - à fixer des moyens de retenue supplémentaires entre un bord avant de ladite nacelle en considérant le sens de déplacement choisi, et un troisième entrait situé en avant
• - à relâcher les quatre câbles portant ladite nacelle de façon à la faire descendre en avançant dans ledit sens de déplacement choisi d'une première distance
• - à décrocher les deux câbles avants et à les raccrocher audit troisième entrait
• - à décrocher les moyens de retenue supplémentaires et à les installer entre un bord arrière de la nacelle et ledit entrait arrière
• - à décrocher lesdits câbles arrières dudit entrait arrière pour les raccrocher à un quatrième entrait situé en avant dudit entrait arrière
• - et à réenrouler les câbles portant ladite nacelle de façon à la faire remonter en avançant dans ledit sens de déplacement choisi d'une seconde distance.

Under these conditions, the invention also relates to a method of moving a nacelle between substantially parallel parts of a frame or connected, said nacelle being hooked, between two displacements, at four points by a set of four cables of adjustable lengths. with two struts, a front streak and a rear streak relative to the direction of travel chosen supporting respectively two front cables and two rear cables, characterized in that an elementary phase of movement consists

• - to fix additional retaining means between a front edge of said nacelle considering the direction of movement chosen, and a third entry located in front
• - to release the four cables carrying said nacelle so as to make it descend while advancing in said direction of travel chosen by a first distance
• - unhook the two front cables and hang them up on said third entry
• - unhook the additional retaining means and install them between a rear edge of the nacelle and said rear entry
• - unhooking said rear cables from said rear entry to hook them to a fourth entry located in front of said rear entry
• - And to rewind the cables carrying said nacelle so as to raise it by advancing in said direction of travel chosen by a second distance.

The control of the four suspension cables allowing the vertical movement of the nacelle is ensured by four electric motors whose power cable is supported by hooks placed on entry or failure as the nacelle progresses in one direction or in the 'other. The four motors are fixed on the platform so that, in the direction x of spacing of the ties or breakdowns, the cables, at this platform, are spaced from p as it was said previously. It has also been said that at the time of the first maneuver, the nacelle is suspended at a distance m from the struts or purlins on two struts transversely distant by a year and that, during the two maneuvers, the cables must be able to be unhooked easily from the nacelle .

The system according to the invention is further characterized in that the distance m is chosen to be equal to the average size of a man, the distance p between suspension cables at the level of the platform being between (a-1) .n and year

It will also be understood that, during displacement maneuvers, the rigid poles are used to cause the displacement of the nacelle by rotation around their anchoring point on the ties or purlins. In other words, for the nacelle to be moved, it is necessary to have anchoring points on the platform. In addition, the platform must be stable regardless of the position of the people working on its surface.

The system according to the invention is also remarkable in that the outputs of the four suspension cables of the nacelle are located at the four corners of the platform which comprises, at these outputs, anchoring devices for the poles.

Under the conditions which have been defined, and as previously specified, the poles have a useful length greater than the length of the suspension cables when the nacelle is at a distance m from the ties or purlins, and we have specified that the movement maneuvers are carried out under the control of the suspension cables.

The system according to the invention is also remarkable in that, during the first movement maneuver over a distance n / 2, the two rigid poles are anchored on the anchoring devices platform at the outputs of the two suspension cables located on the part considered to be the platform front in the direction of the desired movement, and cause, by controlled relaxation of the suspension cables, a lateral movement of the nacelle lined with downward movement until the suspension cables from the rear of the platform reach a length equal to that of the poles, the latter, during the second movement maneuver over the same distance n / 2, being anchored on the platform anchoring devices at the outputs of the two suspension cables located on the rear part of the platform, and causing, by controlled tensioning of the suspension cables, a lateral movement of the nacelle coupled with an upward movement up to 'that the suspension cables reach a length such that the nacelle is at a distance m from struts or purlins.

• - figure 1 : une vue schématique en perspective de la plateforme suspendue aux entraits ou pannes d'une charpente lorsqu'a été effectuée la première opération dela première manoeuvre de déplacement;
• - figure 2a et 2b ': une illustration des deux manoeuvres de déplacement;
• - figure 3 : une vue schématique de la plateforme, la nacelle ayant été déplacée sur une distance n.

The following description refers to the accompanying drawings which represent:

• - Figure 1: a schematic perspective view of the platform suspended from the ties or breakdowns of a frame when the first operation of the first movement maneuver has been carried out;
• - Figure 2a and 2b ': an illustration of the two displacement maneuvers;
• - Figure 3: a schematic view of the platform, the nacelle having been moved over a distance n.

The nacelle 2 has been shown in FIG. 1 in the form of a platform, its components - such as railings, protective mesh - being known components which therefore do not form part of the invention. At the four corners of the platform are fixed four electric motors 21, 22, 23, 24 for driving four suspension cables 31, 32, 33 and 34. Each cable is wound on a mandrel coupled to the axis of the corresponding motor. The nacelle is suspended under a framework, in particular metallic, composed of trusses resting on pillars, the lower part of each truss being constituted by a bar or purlins arranged horizontally, the struts or purlins being parallel and at a distance n the one from the other in the direction of alignment of the trusses, or transverse direction x of the frame. There are shown in the figure five struts or breakdowns 11, 12, 13, 14, 15.

The free ends of the suspension cables are hooked at four points on the frame on two cross sections spaced apart by an "a (an integer of course). In the example shown, the anchoring links are distant from 2.n; these are connections 12 and 14, this arrangement allowing the person working in the nacelle to conveniently clean and / or paint the connection 13 and the other components of the farm of which it forms the lower part, taking account of the dimensions frame standard which will be specified later and the dimension of the platform in the direction x which is chosen between n and 2n in this case.

The end of the suspension cables 31, 32, 33 and 34 is constituted by a rigid part ending in a hook, respectively 311, 321, 331 and 341, the function of which will be specified in the following, as well as the length r . As the direction of movement subsequently chosen is x ′ (see FIG. 1) the entry 12 is called the front entry and the entry 14 is called the rear entry. Cables 31 and 32 are the front cables and cables 33 and 34 are the rear cables.

The nacelle being initially on the ground and resting on four wheels (not shown), any appropriate equipment is used to anchor the hooks of the rigid parts of the four suspension cables to the struts 12 and 14, at points 121, 122 and 141, 142 . The nacelle is then hoisted by the movement of the suspension cables driven by the electric motors, until the platform is at the distance from the ties or breakdowns which is suitable for the work to be carried out.

We will assume that the work is completed at the entry 13 and that we want to carry out the work at the entry 12, which requires moving the nacelle in the direction x, over a distance n, towards the left in the drawing, it being understood - as will be seen later - that the nacelle can be moved both in the x direction and in the y direction. To this end, additional retaining means are available, here in the form of two rigid poles 41 and 42 which are permanently on the platform. As shown in Figure 1, the platform being brought at a distance m from the ties (if it is not already), these poles are anchored, on the one hand, on anchoring devices of the platform at the cable exits 31 and 32, on the other hand, at points 111 and 112 of entry 11 or third entry, that is to say at a distance n from points 121 and 122 for anchoring the abovementioned cables.

We will now refer to FIG. 2a to explain the first maneuver intended to advance the nacelle by a distance n / 2. As has just been said, at the start of the first maneuver, the nacelle is in the position shown in solid lines, at distance m from the ties 111 to 141, suspended by its suspension cables on the ties 12 and 14. The assembly is shown in side view so that only the cables 31 and 34 and the anchoring points 121 and 141 are visible. The rigid poles ( only, the pole 41 is visible) were anchored as shown in FIG. 1.

, ce qui donne, dans le cas plus général d'une distance a.n entre entraits d'ancrage, une valeur 1 égale à

. Cette longueur n'est pas critique car la distance m peut varier dans certaines limites sans inconvénient majeur pour le travail à effectuer.FIG. 2a makes it possible to determine the useful length of the poles 41 and 42. In the case shown, this length 1 will be equal to

, which gives, in the more general case of a distance a between anchoring sections, a value 1 equal to

. This length is not critical since the distance m can vary within certain limits without major inconvenience for the work to be performed.

The nacelle therefore being in the position shown in solid lines in FIG. 2a, a detent movement of the four suspension cables is controlled so that this nacelle, guided in its downward movement by the poles rotating around their anchoring points 111 and 112 (Figure 1), is brought into the position shown in dotted lines in Figure 2a. In this position, the nacelle is in equilibrium, the length reached by the rear suspension cables (33 and 34) is equal to that of the poles, the maneuver having brought about a displacement of the nacelle over a distance equal to n / 2.

In the case shown, the dimension of the platform in the direction x is slightly smaller than 2n, distance between anchoring straps of the suspension cables; it will be noted that, as a result, the length of the front suspension cables, at the end of the first maneuver, is shorter than that of the rear suspension cables. So that the platform remains in a horizontal plane during the first maneuver, it is therefore necessary to control the detent movement of the cables so that the front cables run more slowly than the rear cables; the unwinding speed ratios will be easily deduced from the length 1 'of the front suspension cables at the end of the maneuver, this length 1' being calculated according to the formula ' ² = 1 ² + n ^{2 -} 2 ( nq), with q = (3n - p) / 2 in the case considered and (an + n - p) / 2 in the more general case of a distance an between anchoring straps of the suspension cables. It will be noted that 1 ′ = 1 = length of the poles when the dimension p of the platform is equal to the distance an between anchoring sections, and that q is the dimension defined by the height of the triangle formed by a pole, the cable of corresponding front suspension and their anchor points on rails, on the part front of base of length n of triangle.

When the nacelle has been brought into the position shown in dotted lines in FIG. 2a, it is suspended in the equilibrium position by the poles anchored on its front part and by the rear suspension cables; it is therefore possible to unhook the suspension cables before their anchor point on the link 12 to hang them at the anchor points of the two poles on the link 11, by slightly relaxing them in the case of a platform of dimension p less than 2n (or year), in the proportions shown. The poles can then be unhooked, the nacelle being suspended in the low position by its four suspension cables, then hung so as to "double" the rear suspension cables, the nacelle being always suspended in the low position, but the cables rear suspension can then be removed to be hung on the entry 13 or fourth entry (only, the anchor point 131 is visible in Figures 2a and 2b). The nacelle is then in the position and under the conditions shown in solid lines in FIG. 2b.

It has been said previously that the end of the suspension cables is constituted by a rigid part (311, 321, 331 and 341 in FIG. 1) allowing the cables to be unhooked easily, from the nacelle, during the two movement maneuvers. The length r of this rigid part will, in principle, be determined empirically, and its length r will be specified later with the other dimensions of the assembly produced which will be defined by way of example.

The nacelle being in the position shown in solid lines in FIG. 2b, a tension movement of the four suspension cables is controlled so that this nacelle, guided in its upward movement by the poles rotating around their anchoring points 141 and 142 (Figure 1), is brought into the position shown in dotted lines in Figure 2b. In this position, the nacelle is in equilibrium at distance m from the ties or breakdowns, the maneuver having caused it to move over a distance equal to n / 2. The poles can then be unhooked, and the nacelle is found in the position and under the conditions represented in FIG. 3, which corresponds to a displacement of n from its initial position. It is then possible to treat the line 121 and the components of the farm of which this entry constitutes the lower part.

We have just described the operations carried out during the two maneuvers for moving the nacelle in the direction x and in the direction x ', that is to the left in FIG. 1. It is clear that the same sequence of operations will make it possible to move the nacelle in the other direction for this same direction x, except that the front part of the nacelle is then that where the outputs of the suspension cables 33 and 34 are located. It is also clear that the system according to the invention makes it possible to move the nacelle in the y direction; but, in this case, the upper ends of the poles are hung on the anchoring ties (12 and 14) of the suspension cables, at a distance n from the cable anchoring points of the front part, during the first maneuver.

Note, moreover, that if the lower part of the ties is profiled so as to be able to constitute a running rail, the movement of the nacelle in the direction y can be done by means of driving wheels placed in the ties, the displacement system according to the invention then being used only for displacement in the x direction.

Finally, it should be noted that, if the frame has faults located in an inclined plane, and no longer horizontal, the system according to the invention can still be used; but it is then a little more complex in the sense that it requires the use of four poles of two different lengths to allow the movement of the nacelle, and a more elaborate control of the movements of suspension cables.

A nacelle produced in accordance with the invention comprises a platform whose length is 5m in the y direction and whose width is 2.40m in the x direction. At the start of the first displacement maneuver, the nacelle is or is brought to approximately 1.80 m (distance m) from the ties or purlins, and, for a standardized distance of 1.50m between these ties or purlins, the rigid poles a length of around 2.60m. The ends of the poles are constituted by hooks whose dimensions are adapted to the standardized dimensions of the ties or purlins, and the ends of the suspension cables are in fact constituted by independent rods, these rods ending, at each end, by a hook , and the cables being provided with an anchoring device in the hooks of the lower ends of the rods. Taking into account the dimensions which have just been stated, a length r of the rods of 1m allows easy unhooking of the suspension cables, from the nacelle, during the two displacement maneuvers.

The platform has a 1.10m high railing and a double exterior railing with protective mesh; it is equipped with four electric motors of 500 kg force, with dual control brakes in the event of a power failure. The reduction of the motors is important enough for the maneuvering of raising and lowering of the nacelle can be carried out by controlling its horizontality "on judgment". A safety system using two mercury contactors perpendicular to each other may be provided to automatically cut the power to the motors as soon as the nacelle tilts beyond a certain angle and oblige the operator to correct the tilt.

It is understood that the above description has been given by way of nonlimiting example and that certain variants can be envisaged both with regard to the dimensional characteristics of the system and its applications.

Claims (8)

1. Nacelle movable relative to a structure comprising ties (11, 12, 13, 14) or the like which are substantially parallel, for example a frame, characterized in that said nacelle (2) comprises four cables of variable length (31, 32 , 33, 34) provided at their ends with means of attachment to said ties and connected at four points of the platform defining a quadrilateral and additional retaining means (41, 42), of given length, capable of being fixed so removable between said nacelle and a selected point of said structure. 2. Platform according to claim 1, characterized in that each cable of variable length is terminated by a rigid part forming a hook (311, 321, 331, 341), the length of the rigid part being sufficient for it to be able to be grasped from said pod. 3. Nacelle according to claim 1 or 2, characterized in that the additional retaining means consist of two poles (41, 42), each pole end being provided with a hooking means and in that points d anchoring of these poles are provided on the nacelle, for example in the vicinity of the aforementioned four points. 4. Nacelle according to one of claims 1 to 3, characterized in that it comprises one or more electric motors (21, 22, 23,24) for adjusting the useful length of the four above-mentioned variable length cables. 5. A nacelle according to claim 4, characterized in that each cable (31, 32, 33, 34) is associated with an electric motor (21, 22, 23, 24) and is wound around a mandrel coupled to the motor axis. 6. Nacelle according to one of the preceding claims, characterized in that the direction of displacement (x) being perpendicular to said ties, which are spaced by a distance n, said nacelle is normally suspended from two distant ties (12, 14) of an (a being an integer) at a distance m from the ties with a spacing p between the cable anchors in the direction of movement, such as p ≦ an, and in that the additional retaining means (41, 42) have substantially a useful length 1 such that

and are anchored on the nearest entry (11) in the direction of the desired movement (x ') successively at the front and at the rear relative to the direction of movement to guide by rotatior. two successive displacements of the nacelle of substantially n / 2 each, by lowering and then raising the nacelle. 7. System according to claim 6, characterized in that the distance m is of the order of magnitude of that of a man and in that said distance _E between the cable anchors is substantially between (a-1) n and year 8. Method of moving a nacelle between substantially parallel parts of a frame or ties (11, 12, 13, 14), said nacelle being hung, between two displacements, at four points by a set of four cables of length adjustable (31, 32, 33, 34) with two links, a front link (12) and a rear link (14) relative to the direction of travel chosen (x ') supporting two front cables (31, 32) and two respectively rear cables (33, 34), characterized in that an elementary displacement phase consists - to fix additional retaining means (41, 42) between a front edge of said nacelle by considering the direction of movement chosen; and a third entered (11) located in front - to release the four cables carrying said nacelle so as to make it descend while advancing in said direction of travel chosen by a first distance - to unhook the two front cables (31, 32) and to hook them up to said third entry (11) - unhooking the additional retaining means (41, 42) and installing them between a rear edge of the nacelle and said rear inlet (14) - unhooking said rear cables (33, 34) from said rear entry to hook them to a fourth entry (13) located in front of said rear entry - And to rewind the cables carrying said nacelle (2) so as to raise it by advancing in said chosen direction of movement (x ') by a second distance.

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