EP1486452A2 - System for lifting and stabilising a suspended load support - Google Patents

Abstract

The system has two cable circuits, each having a cable (C1,C2) connected between an end of a fixed point (PF1, PF2) and an end of a lifting apparatus (T1,T2) by deflecting pulleys (A1-A3, B1-B3) mounted on two parallel axes of each end of a load support. One of the pulleys turns in a same direction as that of a pulley of another cable circuit by similar actions of lifting or lowering of the lifting apparatus.

Description

The invention relates to a system for the suspension and lifting of a load support, according to the preamble of the first claim.

We know a type of device for the suspension and lifting a load support, such as a work, according to which this support is suspended by means of four strands of suspension made up in total of at least only two links, such as cables, each hanging at a fixed point on the side of one of the ends of the support load, and passing through circular return supports rotating such as pulleys located at both ends of the load support, to connect each to a means of lifting such as a winch placed above the other end load support. These circular supports are arranged to be in solidarity with the links they support. They can be located not at the ends of the load support but only towards its ends at equal distance from the center of this support, without changing the process for obtaining the result pursued. In general, we recommends that the suspension strands of such a device are arranged vertically, but this one can also apply to oblique strands of suspension. Incidentally, we can specify that the center of gravity (G) of the load support is placed below the strands transverse cables joining the pulleys, so that ensure the transverse stability of the support. This system has the advantage of requiring only two lifting means to four strands of suspension. Figure 1 gives a schematic illustration of such a device.

The device as described above has the disadvantage of present a load support leaning longitudinally from the load side by rolling pulleys on cable when this load moves out of the Ag gravity axis from the support to one of the suspension ends. Through example, as soon as a user, located on such a support constituted by a nacelle, initially horizontal, leaves the center of it to go to one or the other of its ends, the basket leans on the same side. Slope increases until the platform floor approaches a position aligned with the suspension strand of the cable located on the opposite side to that of the displacement of the load, as shown in Figure 2. In practice, in the case where the load support is a nacelle, this movement is limited, without being deleted, by guiding strands of suspension, by means of vertical extensions of the carrycot such as stirrups. Such a movement as well limited is shown in Figure 3.

The following indications refer more particularly to a load support consisting of a nacelle, described successively with one then two links each consisting of a cable passing over pulleys and operated by a winding type winch, but the invention also applies to all lifting means and to all equivalent mounting load carriers, for example those in which the links would be chains, circular cable supports would be sprockets of chains and / or the load support would be a spreader, these embodiments are not limiting. Likewise, the indications below apply to a system such as describes in which at least one of the two links would pass on more than two pulleys on each end axis, in making additional returns between the two support ends. They also apply to the case where the system would have more than two links. The indications below refer more particularly to suspension strands, vertical but the invention can apply in the case of oblique suspension strands if particular reasons justify this provision. specific requirement for mounting by pulleys and cables or straps is that the coefficient of adhesion between pulleys and cables or straps is such that, taking into account the weight of the support and of its load, the cooperation between pulleys and cables or straps are made without slipping cables or straps in the pulley grooves.

The object of the invention is to achieve by means simple a system of the aforementioned type, having the advantage of keep the load carrier in a stable position and unchanged when the point of application of the load is not not or is no longer placed in the center of the support, i.e. equal distance from system suspension points.

The lifting system intended to carry out the invention is applied to the two opposite ends of the support load, which is suspended by at least four strands of suspension consisting of at least two links, each of which is suspended towards one of these ends at a fixed point and towards the other end to the drive member of a lifting device, passing through circular supports deflection, in integral rotation with these two links parallel axes fixed respectively towards each end of the load support, the circular supports located towards the same end being mounted on the same axis. The system being thus arranged, each link of the system according to the invention is linked to its lifting means on the side of the end of the load carrier opposite to that of the side of which the other link is connected to the other lifting means, at least one of the links passing successively on at least two coaxial circular supports located towards each end, following a path such that, on at least one end axes, at least one circular support of the link above rotates in the same direction as at least one support coaxial circular of the other link under the identical action of the two lifting means applying to the links, while these two circular supports are stressed respectively by a couple of the same intensity and in the opposite direction when their common axis is stressed by the same force towards the low, not linked to the action of the lifting means. So in joining together, according to the invention, these two supports circular, the effect of this force is canceled without the action of the lifting means on the circular supports, via links, be hindered.

Therefore, in the case of a nacelle, if the floor of the nacelle, which supports the load, is initially placed in a horizontal position, the device according to the invention keeps it in this position when the person or persons located in this nacelle move from one end to the other of it. The invention makes it possible to reconcile obtaining this result with the operation of the support, in particular of the nacelle, in ascent and descent.

According to an advantageous embodiment, the two links follow each a path on at least two circular supports at each end of the charging stand, so that can join their respective movements to the two ends of the load carrier on at least two carriers contiguous circulars, directly connecting these between them.

According to another advantageous embodiment, the two links each follow a path on at least two supports circular at each end of the load support, so that we can unite their respective movements at both ends of the load carrier on at least three contiguous circular supports, in order to connect directly these between them.

Other advantageous characteristics are defined in dependent claims 4 to 8.

Les figures 1 à 3 représentent un système pour la suspension et le levage d'un support de charge selon la technique antérieure ;

Les figures 4 à 10 représentent un schéma élémentaire d'un système pour la suspension et le levage d'un support de charge ;

La figure 11 représente un système à deux câbles correspondant à la figure 1 ;

La figure 12 représente un système a deux câbles dont les treuils se trouvent au-dessus des côtés opposés du support ;

La figure 13 représente un système à deux câbles dont les treuils se trouvent sur le même côté du support, et dont un câble est mouflé sans croisement du mouflage ;

La figure 14 représente un système à deux câbles dont les treuils se trouvent au-dessus des mêmes côtés du support, et dont un câble est mouflé avec croisement du mouflage ;

La figure 15 représente un système selon un premier mode d'exécution de l'invention, c'est-à-dire un système à deux câbles dont les treuils se trouvent sur les côtés opposés du support, et dont un circuit de câble est mouflé avec croisement du mouflage, et avec deux poulies appartenant à un circuit de câble différent, mais tournant dans le même sens sous l'action identique des deux treuils et sollicitées en sens inverse en cas de déplacement de la charge sur le support, solidarisées l'une de l'autre ;

La figure 16 représente un système selon l'invention dont deux les circuits de câble sont mouflés ;

Les figures 17 à 22 représentent différents modes d'exécution de l'invention, selon lesquels les deux circuits de câble sont mouflés, et qui se distinguent par la solidarisation de différentes poulies ;

Les figures 23A et 23B représentent en coupe les trois poulies montées sur l'axe commun de gauche du mode d'exécution de la figure 15, la poulie intermédiaire appartenant au circuit de câble mouflé étant solidarisée à la poulie appartenant au circuit de câble simple dans la figure 23A et ces deux poulies étant désolidarisées dans la figure 23B ; et

Les figures 24A et 24B représentent en coupe les quatre poulies montées sur l'axe commun de gauche du mode d'exécution de la figure 19, la poulie intermédiaire appartenant au premier système de câble mouflé étant solidarisée à la poulie double appartenant à l'autre système de câble mouflé, dans la figure 24A et ces poulies étant désolidarisées dans la figure 24B, et avec un dispositif antichute pour chaque axe d'extrémité ;

Les figures 25A et 25B montrent le système de la figure 19 avec un système antichute pour chacun des deux axes ; et

La figure 26 représente un système d'exécution préféré avec les tambours des deux treuils calés sur l'axe d'un même moteur.

The system for the suspension and lifting of a load support will now be explained in greater detail with respect to the appended figures, in which:

Figures 1 to 3 show a system for the suspension and lifting of a load support according to the prior art;

Figures 4 to 10 show a basic diagram of a system for the suspension and lifting of a load support;

Figure 11 shows a two cable system corresponding to Figure 1;

FIG. 12 represents a system with two cables, the winches of which are above the opposite sides of the support;

FIG. 13 represents a system with two cables, the winches of which are on the same side of the support, and one cable of which is hauled without crossing the haul;

FIG. 14 represents a system with two cables, the winches of which are above the same sides of the support, and one cable of which is hauled with cross hauling;

FIG. 15 represents a system according to a first embodiment of the invention, that is to say a system with two cables, the winches of which are on the opposite sides of the support, and of which a cable circuit is mouflaged with haulage crossing, and with two pulleys belonging to a different cable circuit, but rotating in the same direction under the identical action of the two winches and urged in the opposite direction in the event of movement of the load on the support, secured to it one of the other;

FIG. 16 represents a system according to the invention, two of the cable circuits of which are hauled;

Figures 17 to 22 show different embodiments of the invention, according to which the two cable circuits are mouflaged, and which are distinguished by the joining of different pulleys;

FIGS. 23A and 23B show in section the three pulleys mounted on the common left axis of the embodiment of FIG. 15, the intermediate pulley belonging to the reeved cable circuit being secured to the pulley belonging to the simple cable circuit in FIG. 23A and these two pulleys being separated in FIG. 23B; and

FIGS. 24A and 24B show in section the four pulleys mounted on the common left axis of the embodiment of FIG. 19, the intermediate pulley belonging to the first reeved cable system being secured to the double pulley belonging to the other cable cable system, in FIG. 24A and these pulleys being separated in FIG. 24B, and with a fall arrest device for each end axis;

Figures 25A and 25B show the system of Figure 19 with a fall arrest system for each of the two axes; and

FIG. 26 represents a preferred execution system with the drums of the two winches fixed on the axis of the same engine.

In order to facilitate understanding of the invention and its characteristics of novelty, we will recall the properties of the simplest front suspension and lifting system implementation of the invention, consisting of a single cable suspension operated by a single winch. We will then show how the invention allows, by doubling the cable lifting, to get the intended result.

We will call "A" the pulleys located on the left axis and “B” the pulleys located on the right axis.

We will reason on the example of a cable, the reasoning of a cable being applicable to any link likely to cooperate with a circular support.

I / Description of an elementary system diagram suspension and lifting

Figure 4 shows a suspension and lifting system known load comprising on the one hand a support or nacelle S, which can be diagrammed in plan by a chassis rectangular, comprising, on the one hand at each end considered in the longitudinal direction, a transverse axis Ax, the two axes Ax being horizontal parallel, and carrying each of a pulley A, B, and on the other hand a cable C for the suspension of the support S, said cable C being fixed in a upper point Pf located vertically above a end of the support S, passing through the two pulleys A, B of this and then winding up to a T winch fixed in one point vertically above the other end of the support S.

FIG. 4 shows a diagram of support S in elevation, and Figure 5 the corresponding diagram in plan. These diagrams can be applied to structures other than a nacelle, for example to a lifting beam.

In the following explanations concerning this invention, we will only represent cables and pulleys in order to simplify the diagrams. It is understood that the axes pulleys supporting the suspension cables are integrated into the support to ensure suspension and vertical movement of it. So the figure above 4 will be represented according to FIG. 6.

In the following explanations concerning the meaning of rotation of a pulley, we will always consider it in a downward movement of its axis.

a) On peut considérer un tel système en position statique horizontale d'équilibre lorsque la charge appliquée au support S, se répartit à égalité à chaque extrémité dudit support, étant entendu que le poids mort du support est également réparti. Dans ce cas, si le treuil T, situé par exemple du côté gauche du support S, déroule le câble C, le support S descendant en gardant sa position horizontale, les deux poulies A, B, entraínées par le mouvement du câble C, vont pivoter dans le même sens, c'est-à-dire toutes deux dans le sens inverse des aiguilles d'une montre (SIA). Si le treuil T avait été situé du côté opposé, c'est-à-dire du côté droit, les deux poulies A, B, pour le même mouvement de descente du support S, auraient tourné en sens inverse, c'est-à-dire toutes deux dans le sens des aiguilles d'une montre (SDA). Cette comparaison est illustrée par la figure 7 dans le cas où le treuil T est situé du côté de l'extrémité gauche du support S, et par la figure 8 dans le cas où le treuil T est situé du côté de l'extrémité droite. Sur les figures 7 et 8, et sur les figures suivantes on indique pour chaque poulie son sens de rotation par une flèche pleine pour le cas de mouvement ci-dessus.

b) Si maintenant, le treuil T étant à l'arrêt, la charge, initialement équilibrée, se déplace vers l'extrémité gauche du support S, cette extrémité sera soumise à une force vers le bas, et le support penchera de son côté, ce qui fera déplacer en roulement les deux poulies A et B sur le câble C immobile, de sorte que la poulie de gauche A soumise à cette force va descendre. De son côté, la poulie B située à droite va monter, puisque la longueur totale de câble C restant fixe ainsi que celle du brin reliant les deux poulies A et B, le brin vertical de droite doit se raccourcir. Dans son mouvement de descente, la poulie de gauche A va, en roulant sur le câble C immobile, tourner dans le sens SDA, c'est-à-dire dans le sens inverse de celui SIA où elle tournait sous l'action de descente du treuil T situé au dessus d'elle. On a figuré sur la figure 9 un stade de ce mouvement en cours pour une charge décalée vers la gauche sur la figure. Par contre, si, précédemment, dans le cas ci-dessus b), cette même poulie de gauche avait été située sous le point fixe de suspension Pf, le treuil ayant été situé de l'autre côté du support S, cette poulie A, dans son mouvement de roulement vers le bas, se déplacerait sous l'effet du déplacement de la charge dans le même sens que précédemment (SDA) sous l'action de descente du treuil T, comme montré sur la figure 10. En effet, dans le phénomène considéré, le côté où est situé le treuil n'importe plus, puisque le treuil T est immobile et se comporte comme le point fixe opposé.Sur les figures 9 et 10 et sur les figures suivantes on indique pour chaque poulie son sens de rotation par une flèche en pointillé pour le cas de mouvement ci-dessus.Les sens de rotation, dans ce cas, sont naturellement identiques quel que soit le côté où se trouve le treuil T, alors qu'ils se trouvaient inversés par changement de côté du treuil, lorsque le mouvement des poulies était provoqué par celui du treuil.

c) On peut donc en conclure qu'il y a deux cas de mouvement possibles du système :

1/ Un cas dans lequel le mouvement est engendré par le treuil T, le câble C entraínant par son mouvement la rotation des poulies A et B (flèches pleines),

2/ l'autre cas dans lequel, le treuil étant à l'arrêt, le mouvement est engendré par le roulement des poulies A et B sur le câble C immobile lorsque la charge se porte à l'une des extrémités du support (flèches en pointillé).

Two cases of movement of each pulley are to be considered.

a) One can consider such a system in a horizontal static equilibrium position when the load applied to the support S is distributed equally at each end of said support, it being understood that the dead weight of the support is also distributed. In this case, if the winch T, located for example on the left side of the support S, unwinds the cable C, the support S descending while keeping its horizontal position, the two pulleys A, B, driven by the movement of the cable C, will rotate in the same direction, i.e. both counterclockwise (SIA). If the winch T had been located on the opposite side, that is to say on the right side, the two pulleys A, B, for the same downward movement of the support S, would have rotated in opposite directions, that is to say - both say clockwise (SDA). This comparison is illustrated by FIG. 7 in the case where the winch T is situated on the side of the left end of the support S, and by FIG. 8 in the case where the winch T is situated on the side of the right end. In FIGS. 7 and 8, and in the following figures, each direction of rotation is indicated by a solid arrow for the case of movement above.

b) If now, the winch T being stopped, the load, initially balanced, moves towards the left end of the support S, this end will be subjected to a downward force, and the support will lean on its side, which will move the two pulleys A and B in rotation on the stationary cable C, so that the left pulley A subjected to this force will descend. For its part, the pulley B located on the right will go up, since the total length of cable C remains fixed as well as that of the strand connecting the two pulleys A and B, the vertical strand on the right must be shortened. In its downward movement, the left pulley A will, by rolling on the stationary cable C, turn in the direction SDA, that is to say in the opposite direction to that SIA where it turned under the action of descent of the T winch located above it. There is shown in Figure 9 a stage of this movement in progress for a load shifted to the left in the figure. On the other hand, if, previously, in the above case b), this same pulley on the left had been located under the fixed point of suspension Pf, the winch having been located on the other side of the support S, this pulley A, in its downward rolling movement, would move under the effect of the movement of the load in the same direction as before (SDA) under the action of lowering the winch T, as shown in Figure 10. Indeed, in the phenomenon considered, the side where the winch is located no longer matters, since the winch T is stationary and behaves like the opposite fixed point. In Figures 9 and 10 and in the following figures, each direction is indicated for rotation by a dotted arrow for the above case of movement. The directions of rotation, in this case, are naturally identical regardless of the side where the T winch is, while they were reversed by changing side of the winch, when the movement of the pulleys was caused by that of the winch.

c) We can therefore conclude that there are two possible cases of movement of the system:

1 / A case in which the movement is generated by the winch T, the cable C causing by its movement the rotation of the pulleys A and B (solid arrows),

2 / the other case in which, the winch being stopped, the movement is generated by the rolling of the pulleys A and B on the stationary cable C when the load is carried at one of the ends of the support (arrows in dotted).

In the second case, the direction of rotation of a pulley A or B, for a vertical movement in the same direction as in the first case, will be the same as in this first case for the pulley located on the side of the fixed point of suspension, and will reverse for the pulley located on the side of the winch.

Naturally, the two cases of movement can be found combined simultaneously, the load moving on the support while the winch T makes it go up or down.

II / System developed by doubling the cable

You may want to mount the system with two cables C1, C2 to place of one. This activates four strands of suspension by two winches T1, T2 only, and thus double the security.

If these cables are mounted identically, the result will be the same as before. Figure 11 illustrates this mounting, doubling that of figure 8.

If the winch T2 of the second cable C2 is placed on the side opposite to that of the first winch T1, the movement of the support S will still be the same in both operating cases above, but the direction of rotation of each pulley A ', B' of the second cable C2 will, in the case of displacement vertical by winches T1, T2, opposite with respect to the direction of rotation of pulley A or B located in position corresponding on the first cable C1, for the same direction of vertical displacement as in the previous assembly. In other words, the coaxial pulleys A, A 'and B, B' (each belonging to a different cable) will rotate in opposite directions one from the other. In this case, the coaxial pulleys A, A ' and B, B 'must be mounted free on their axis Ax. The Figure 12 illustrates this arrangement.

In all cases, the winches must naturally wind and unwind the cable at a linear speed identical to obtain a suitable vertical movement of the support.

III / System developed by reeving one of the two cables

The object of the invention is to stabilize the position of the support in the event of displacement of its load while allowing its two cables to go up or down at the same time time under the action of their respective winches.

To this end, and as shown in Figure 15, we muffle at least one of the two cables, passing it over the minus two pulleys A2, A3 and B2, B3 on each Axis axis end of the support, i.e. on at least four pulleys, so as to obtain a cable circuit such that, on the same axis Ax we get that a pulley belonging to the hauled circuit rotates in the same direction as the coaxial pulley A1, B1 of the circuit not reeled under the identical action of the two winches (lowering or ascending) and are requested, by a load off center, in a reverse rotation direction to that of circuit pulley not reeved, in a rolling movement on stationary cables. The result of the invention is then obtained by joining these two pulleys.

The pulleys A1, A3, B1 will be called "end pulleys" B3 located at the lower end of the vertical strands, and "Intermediate pulleys" the other pulleys A2, B2, that is to say those which are connected by transverse strands, each only to a different pulley.

We will call A1 the left pulley (in direct suspension) single cable, A2, the left middle pulley of the mouflé cable and A3, the left end pulley of the cable reeved. We will give the corresponding numberings to pulleys on the right.

The unmouflaged C2 cable will be called "single cable".

A / Tilt movement under the effect of a load off center on the support, the winches remaining stationary.

We have seen that, for this type of movement, the position of the winches T1, T2 is indifferent. So let's assume, for present the simplest scheme, as the two T1 winches, T2 are placed on the same side, for example on the right side, the haulage connecting pulleys A2, A3 and B2, B3 without crossing, according to figure 13. Take the case of charge moving to the left.

We have seen that the end pulleys A1, A3 and B1, B3 located on the same side (therefore coaxial and directly suspended, whether at a fixed point or a winch), are solicited in the same direction of rotation by a shift of the support load. For example, for a displacement of the load to the left, and therefore a downward movement, the two pulleys A1 and A3 go turn in the SDA direction. By crossing the indicated haul in FIG. 13 between the pulleys A2 B2 and B3, according to the figure 14, we will reverse the direction of rotation of the pulley A2 to obtain the opposite direction SIA.

If we joined the pulleys A1 and A2, we would therefore obtain the desired stabilization result, since these two pulleys, each belonging to a cable circuit different, would then be solicited, under the effect of a displacement of the load on the support, by couples equal and inverse. To this end, the coaxial pulleys secured must have the same original diameter.

The word "crossing" means that a strand of transverse cable goes from the bottom side of an end pulley to one side upper of an intermediate pulley, the cable strand next transverse goes from the bottom side of the pulley aforementioned intermediate to the upper side of the other intermediate pulley and the subsequent transverse strand goes from lower side of the other intermediate pulley to the side bottom of the other end pulley.

B / Vertical movement of the support under the action of the winch (centered load)

By reversing the direction of rotation of the pulley A2, by cross hauling, we have reversed its direction of rotation in the case of displacement of the load, by rolling on the fixed cable C1, but we also reversed its direction of rotation under the action of the winch T1 of its cable C1, which winch, in the example chosen, is located on the opposite side to this pulley (on the right in the figure). This meaning is found therefore inverse of that of pulley A3, and therefore of that of pulley A1, since the two winches are located in the same side. It follows that if we join the pulleys A1 and A2, the vertical movement of the support can no longer be done.

In order to restore the same direction of rotation to the pulleys A1 and A2 under the identical action of the two winches, so we will pass one of the two winches on the opposite side of the support. For example we will pass the winch to the left single cable C2. Therefore, we will reverse the direction of rotation of the pulley A1 under the action of its winch, since we saw above that an end pulley rotates, under the action of the winch of its cable, in the opposite direction, depending on whether it is on the side of the fixed point or on the side of the winch. This arrangement is illustrated in Figure 15.

Thus the pulleys A1 and A2 will rotate in the same direction and at the same speed under the identical action of the two T1 winches, T2. On the other hand, they will remain solicited in the opposite direction if the load moves on the support.

So we can join them together to get the result sought, i.e. blocking any tendency to do tilt the support S in the longitudinal direction, while now a normal vertical maneuver of the support S by its winches T1, T2. This solidarity is shown on the figure 15 by a thick line connecting the center of the pulley A1 to that of pulley A2. It can be carried out either by a blocking of the hub of these pulleys A1, A2 on their axis common, on which the pulley A3 turns freely, either in making a pulley with two grooves.

It is easy to understand that the result is identical, that the load moves to the left or to the right. We also easily understands that the result is identical, whichever side the winch of the reeved cable or the single cable is placed, provided that the two winches are placed opposite each end of the support. Thus, we would have obtained the same result by passing to left the cable winch in place of the cable winch simple.

IV / System developed by doubling hauling

We can see that, in the system described, the link does not wraps only about a quarter of a turn on each of the two pulleys A1, B1 of the single cable circuit, one of which single pulley creates cable / pulley adhesion for neutralize the off-center load. Especially, in the case of a mounting by cables and pulleys, it is advantageous to extend the cable winding arcs as far as possible pulleys to improve cable / pulley adhesion including depends on the proper functioning of the system.

To this end, it is advantageously possible to also muffle the two cable circuits to obtain the assembly illustrated by Figure 16.

This last assembly also offers a greater choice of joining modes since it places on each Ax axis four pulleys instead of three.

In this diagram and the following, we will call B0 the pulley right middle of the cable for the new haul and A0 the corresponding pulley on the left.

To better balance the functioning of the system at both ends of the nacelle, especially whatever the direction of displacement of the load, it will be advantageous to complete the connection of pulleys A1 and A2 by connection of pulleys B0 and B2 by joining them together on their common axis, which allows including significantly increasing grip cable / pulley. The pulleys B3 and B1 remain in free rotation, as well as A0 and A3, according to figure 17.

Possible cases of joining are indicated according to Figures 18 to 22. Preferably choose the mounting of FIG. 19 by which, at the two ends of the nacelle, up to three contiguous pulleys are secured for the result sought, instead of which we can use triple grooved pulleys.

In Figures 17 to 22, the connections between pulleys coaxial are represented by thick lines as on the figure 15. The execution mode of figure 19 corresponds to that of figure 18 except the joining and the mode of execution of figure 21 corresponding to that of figure 20 except the joining.

V / Disconnection device

It may be advantageous to make a maneuver possible intended to restore the horizontality of the load support, if this horizontality has been altered. This alteration can be produce, for example, after a certain time of functioning, in the case of a co-operating link by adhesion with pulleys, when there has been a gradual slip of the link in the pulley groove, especially under the effect of a large load that is frequently off-center from the same side. We may also want to cause an inclination determined of the load support, in particular if it is a spreader. To this end, the present invention encompasses all punctual separation system for coaxial pulleys secured. For this, we can imagine that the pulleys coaxial joined together by blocking their hub on their common axis, while the pulley (s) non-secured rotate freely on the same axis. The separation device then consisted, according to a known means, to separate the hubs of their axes from their axes coaxial pulleys normally secured in rotation with these axes.

Such a separation device is shown on the FIGS. 23A and 23B which each represent the pulleys A1, A2 and A3 mounted on the left axis Ax of figure 15. On these figures the left axis Ax rotates in two bearings R, R mounted in a CA cage attached to the support S below of it. Pulley A1 belonging to the circuit of single cable C2 is fixed by a key CL to the axis Ax to shoot with this one. Each of the other A2 pulleys and A3 belonging to the C1 cable circuit is mounted by a bearing R2, respectively R3 on the axis Ax. According to Figure 23A the pulley A2 is secured to the pulley A1 by a locking screw V tightened on the axis Ax so that this pulley A2 is integral with axis Ax and therefore with pulley A1 keyed on this axis Ax. This locking screw V also serves means of separation because it allows, after loosening and disengaging the axis Ax the free rotation of the pulley A2 on the axis Ax.

FIG. 24A shows the joining of the pulleys A0, A1 and A2 on the left axis Ax of the embodiment of the figure 19 to two circuits of tapped cables C1 and C2. The pulleys A0 and A1 belonging to cable C2 are joined by the use of a double pulley and the pulley A2 is secured by the locking screw V to the axis Ax and therefore to the pulley double A0-A1. To separate pulley A2 from pulley double A0-A1 the screw V is loosened and released from the axis Ax (see figure 24B)

VI / Fall protection device

According to one embodiment, it may be advantageous to remedy a possible break in one of the two links. This break would neutralize the system, and, in the event of load offset, the support could suddenly bow down to a position close to the vertical. In order to avoid this consequence, this invention also encompasses integration into the system a fall arrest system that snaps onto the coordinated end pin to block it in case of acceleration of its rotational movement beyond a degree of acceleration and / or rotational speed determined, in particular following the rupture of one of the two connections.

Figure 25A shows an embodiment of Figure 19 with such a DA fall arrest device provided for each of the two end axes Ax. Each DA fall arrest system is supported by the associated cage CA of type A pulleys respectively type B and each of these devices fall arrest DA has a fixed BT box and a D disc keyed on the associated axis Ax for rotation therewith. The disc D is provided on its circumference with several notches E and a BI ball or roller is received in each notch E. In the event of a cable break, for example the cable C1, under the effect of the acceleration of the axis Ax and disc D the BI balls or rollers are forced radially outwards from the notches E to come block inside the BT box and block any shaft rotation Ax. Figure 25B shows a view of above the device system of Figure 25A with a DA fall arrester attached to cage CA at the end of the axis Ax on the side of the two separate pulleys A2, A3 respectively B0, B1. Figures 24A and 24B also show the DA fall protection device mounted on a support plate PL welded to cage CA.

VII / Preferential solution

According to a preferred embodiment, represented by the figure 26, instead of having a winch located vertically above from each end of the support, making a total of two winches, we can have a winding of the two strands vertical system currents around two drums 10, 11 or drive pulleys wedged on the axis of the same engine Mr.

For this purpose, the two strands considered pass at the end upper of their vertical path around a pulley of reference 12, 13, and then follow a horizontal path one towards each other to another return pulley 14, 15 their giving directions again parallel close one on the other to allow their winding or unwinding simultaneous on two rotating winding members or of the same winch 16. Figure 26 represents an example of such an assembly with the preferred version double haul.

This assembly can itself be integrated into a trolley remotely actuated to allow translation of the support in addition to its vertical movement. Likewise, this montage can be combined with fall protection or known anti-roll on conventional mounting types.

The system described above can operate with straps instead of cables, and with pulleys whose grooves have the appropriate profile. It can work also with chains instead of cables and sprockets instead of pulleys. Support can take in particular the shape of a nacelle or a platform of site, on which cables, or equivalent links, are guided at the top of the end stirrups by adequate devices. It can also be used for the vertical operation of a lifting beam, or any other load support with the correct configuration for the application of the invention.

Claims (8)

System for the suspension and lifting of a load support, applied towards two opposite ends of this support, the support being suspended by at least four suspension strands constituted by at least two links, each of which is suspended towards one of these ends at a fixed point and towards the other end to the drive member of a lifting device, passing through circular return supports, in integral rotation with these links on two parallel axes fixed respectively towards each end of the load support, the circular supports located towards the same end being mounted on the same axis,
characterized in that each link being connected to its lifting means on the side of the end of the load support opposite to that on the side of which the other link is connected to the other lifting means, at least one of the links pass successively on at least two coaxial circular supports located towards each end, along a path such that, on at least one of the end axes, at least one circular support of said aforementioned link rotates in the same direction as at least a coaxial circular support of the other link under the identical action of the two lifting means applying to the links, while these two circular supports are stressed respectively by a torque of the same intensity and in the opposite direction when their common axis is stressed by the same downward force, not linked to the action of the lifting means, so that by joining these two circular supports, the effect of this force is canceled without the action of the lifting means being r circular supports, via links, are hindered. System according to claim 1, characterized in that the two links each follow a path on at least two circular supports at each end of the load support, so that their respective movements can be secured to the two ends of the load support on at at least two contiguous circular supports, in order to directly connect these between them. System according to claim 1, characterized in that the two links each follow a path on at least two circular supports at each end of the load support, so that their respective movements can be secured to the two ends of the load support on at minus three contiguous circular supports, in order to connect them directly to each other. System according to any of the claims previous, including a device for separating coaxial circular supports normally joined together, in order to make them punctually and temporarily independent by rotation of each other or each other, and allow thus to manipulate them to restore the horizontality of the load support when necessary, or to adjust a desired tilt of it. System according to any one of the preceding claims, characterized in that the links consist of cables or straps, cooperating with pulleys of corresponding peripheral profile, said cables or straps having a coefficient of friction necessary for their good attachment in their cooperation with pulleys. System according to any one of claims 1 to 4, characterized in that the links are constituted by chains and the circular supports by sprockets whose teeth correspond to the configuration of these chains. System according to any one of the preceding claims, characterized in that the upper part of each link suspension strand connected to a lifting means is returned laterally to the other strand, the two strands thus brought together being returned a second time according to a direction parallel to each other and in an identical direction to wind on two winding members, integral with the same drive device. System according to any of the claims previous, including at least one device system fall arrester that engages on one of the end axes, to block it in case of acceleration of its rotational movement beyond a degree of acceleration and / or speed of rotation determined, in particular following the rupture of one of the two connections.

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