EP1170047B1 - Lifting and positioning device for an item of scenery or an accessory in a theatre - Google Patents

Abstract

The theatre backdrop lifting hoist is mounted in a frame, with the backdrop or other accessory suspended from a cable (8), with brake (7) to hold the backdrop raised. An auxiliary cable (21) is fixed to the frame and attached at both ends. the brake is mounted on the main cable to engage the auxiliary cable and has a slide with a cam (125) and counter cam (22).

Description

The present invention relates to a device for lifting of decorations or accessories in a performance hall, for example in a theater, the load, that is to say the decor or accessory, being suspended from a cable suspension. The device also includes means for maintaining the load in a raised position.

We already know in the prior art devices of this kind, and in particular that described in the patent French N ° 2.701.700 of 19 February 1993 in the name of the Applicant. This previous document describes a device to lift and hold loads, especially stage sets, which hang from a suspension cable, the suspension cable being fixed to a slide which slides in a fixed vertical guide rail. He is in additionally provided a traction system consisting of a cable and a motor which, when they cooperate with the slide slide the slide up or down the bottom to raise or lower the chosen decor. A Once the decor is in position, the system described in this prior art document provides for removing the cable from lifting and the motor to assign them to another setting. However, once the motor and the lifting cable are removed, it is necessary to exert an action on the slide for the hold in position. That is to say, replace the lifting force which is exerted by the device lifting on the slide by a holding action of the slide in position, for example on the guide rail.

To this end, the document of the prior art provides several holding or fixing systems. All these fastening systems consist of systems mechanical attachment of the slide to the guide rail, for example by means of a lever and a hook locking, or by a rack and pinion system.

These systems are complicated to implement on the one hand, and on the other hand exhibit stability doubtful. Indeed, for example in the case of the rack, the relative progression of the teeth of the rack in the grooves formed in the rail guidance is not changed depending on the tension exerted by the suspension cable on the slide and in particular is not changed to move to a position in which the attachment of the slide to the guide rail is even stronger when the tension exerted by the suspension cable on the slide. At the slightest defect or vacuum, for example in the case of a jolt, it may happen that the teeth of the rack come out of grooves of the rail and thus the decor collapses. The current systems, to overcome these drawbacks, on the one hand need to be manufactured with tolerances very restrictive, and on the other hand to be fitted with a high accuracy, which in existing buildings, often old, results in very high costs.

The invention overcomes these drawbacks by proposing a device for lifting and positioning a load which allows the lifting of the lifting cable to be assigned to another decor and the possibility of reassigning this cable lifting at the same lifting device and which, once the lifting cable has been removed, keep this load in fixed position in a secure manner, and more particularly sure that in the case of the device of the prior art, and in particular by blocking means such as the position of blocking of the slide with respect to the guide rail modifies according to the tension exerted by the load on the slide and in particular tends towards a position such that the stroke of the slide blocking means for unlocking is all the greater the greater the tension or traction exerted by the suspension cable on the slide.

According to the invention, a device for lifting and positioning is as defined in claim 1.

We thus obtain a system which on the one hand allows removing the lifting cable to assign it to another decor and the replacement of this cable to lift or again lower the decor in question and that maintains on the other hand particularly well in position the load, and especially who is less sensitive to jolts and is therefore safer, and in particular better absorbs jolts.

Indeed in the documents of the prior art, for example US-A-3273671 the lifting cable cannot be removed when in the energized position and this prior art device provides for braking only in case the lifting cable breaks.

According to the invention on the contrary one can, thanks to prior clamping devices, in particular manual ones, block the slide and, by unrolling a little of the cable lifting, unhook the latter from its attachment means and thus assign it to another decor.

According to an improvement of the invention, the automatic clamping means are arranged so as to ability to wedge auxiliary cable in a fold reversible preference, the reversible fold being all the more pronounced that the load is heavy.

By thus planning to bend the auxiliary cable especially since the jamming is important, we make sure as the support is all the more secure as the force exerted by the load (its weight) is large. The race for resources automatic jamming to loosen will be all longer than the fold will be pronounced, these penetrating deeper into the auxiliary cable as the load will be heavy.

According to an advantageous embodiment, the automatic clamping means comprise a cam and a counter cam mounted on the slide, the cam wedging the auxiliary cable against the cam follower.

According to an advantageous embodiment, the cam and the cam follower are vertically offset one by compared to each other. Training is easily obtained crease in the auxiliary cable wedged between the cam and the against cam follower.

According to an advantageous embodiment, the cam is rotatably mounted on the slide while the counter cam is mounted fixed.

According to an advantageous embodiment, the slide slides in a fixed guide rail.

According to an advantageous embodiment, it is provided a link articulated to the cam and integral in translation of the suspension cable.

According to an advantageous embodiment, it is further provided a connecting rod articulated to the cam and capable of be attached to a lifting cable.

Advantageous embodiments and improvements of the invention are defined in the subclaims.

La figure 1 est une vue d'ensemble d'un dispositif suivant l'invention ;

La figure 2 est une vue plus détaillée d'une partie du dispositif de l'invention, en position non bloquée ;

La figure 3 est une vue identique à la figure 2, dans une position partiellement bloquée, c'est-à-dire bloquée manuellement ;

La figure 4 est une vue du dispositif des figures précédentes en position bloquée ; et

La figure 5a représente un mode de réalisation en variante d'un dispositif suivant l'invention, notamment un mode de réalisation en variante des organes de blocage préalable,

La figure 5b étant une vue en coupe transversale de la figure 5a,

La figure 6a représentant le système de la figure 5a en position bloquée ; et

La figure 6b étant une vue en coupe transversale de la figure 6a.

An embodiment of the invention will now be described, given solely by way of example with reference to the drawings, in which,

Figure 1 is an overview of a device according to the invention;

Figure 2 is a more detailed view of part of the device of the invention, in the unlocked position;

Figure 3 is a view identical to Figure 2, in a partially locked position, that is to say manually blocked;

Figure 4 is a view of the device of the preceding figures in the locked position; and

FIG. 5a represents an alternative embodiment of a device according to the invention, in particular an alternative embodiment of the prior locking members,

FIG. 5b being a cross-sectional view of FIG. 5a,

Figure 6a showing the system of Figure 5a in the locked position; and

Figure 6b is a cross-sectional view of Figure 6a.

In Figure 1 it is shown so schematic a performance hall 1, in particular a theater which has a plurality of mobile charges 2, these charges can constitute for example a decoration or accessories. Each load 2 is suspended by at least one cable 3 to one transverse beam 4, called the supporting beam. Beam 1 is suspended from a plurality of cables which in the upper part each goes through a deflection pulley 6 to reach a slide 7, by being hooked each to this slide or by being joined to a common suspension cable 8. The slide 7 can move along a guide rail which is located on one side in vertical position. Rail 9 of guide allows the slide 7 to move vertically only. The slide 7 also has a point for hanging a lifting cable 10 which by via a return pulley 11 is connected to a motor 12, preferably electric. According to Figure 1, the guide rail 9 is in vertical position and motor 12 is in a room 14 below stage 15. The installation comprises a plurality of loads 2 and one or a plurality, but fewer, of motors 12. In particular, it is possible to provide only one motor for all the loads. Motor can slide on rails horizontal arranged on the floor of the chamber 14, to come and place themselves in different positions, each position corresponding to a position in which the motor 12 and its associated lifting cable 10 will be able to cooperate with the slide 7 of the respective load 2 relating to this engine location. We will be able to lift a load 2 given by the action of the motor 12, then once the load has been brought to its desired position, hang or fix the slide 7 after blocking using lever 25, then remove cable 10 from lift and motor 12, slide motor 12 to another position on which he will raise a new load or lower this load according to the needs of the director and then so on go to each of decorations or accessories to raise, lower or maintain in square. We can either program the movement by computer motor 12 and its associated cable, i.e. if, for example, knows in advance that there will be for example among a dozen or twenty accessories and decorations that three or four sets that will be necessary for the piece played in question, provide a corresponding number of motors, i.e. only three or four motors which will each be arranged "fixed" at each position corresponding to a charge that is going to be necessary to stage the room.

Figure 2 is an enlarged view of the slide of Figure 1. The slide 7 has a connecting rod 13 of attachment, to which the cable 10 of lifting associated with the lifting motor 12. The connecting rod 13 is at a point of articulation 14 to a cam 15 constituted a disc whose axis 16 is eccentric relative to the middle of the disc. This cam 15 also has another point 17 of articulation where is fixed a connecting rod 18 which cooperates with an upper part 19 of the slide to which can be fixed at a point 20 for fixing the cable 8 suspension. Slide 7 and its part 19 slide in the guide rail for example by a stop system. In addition, an auxiliary cable 21 extends vertically in the theater, parallel to the rail 9 guide. The auxiliary cable 21 is secured to the building, in particular by being attached to it at its two ends. The guide rail 9 is fixed relative to the theater. The auxiliary cable 21 is also fixed relative to the theater. The auxiliary cable 21 is at a given distance from the guide rail so that the cam 15 is in contact with him. Cam 15 is movable in rotation relative to the point 16 of articulation with respect to the slide 7. The slide 7 further comprises a cam follower 22 fixed relative to to the slide 7. The cam follower 22 is in contact with cable 21.

When the lifting cable 10 is fixed to the slide 7 via the connecting rod 13 of fixing, it exerts an action on the cam 15 so that it is in the position shown in the figure 2, that is to say in a position such as the link 18 hooking is parallel to the connecting rod 13 hooking. In this position, the clearance between the cam 15 and the cam follower 22 is sufficient to allow the slide to slide on the one hand along the rail 9 of guide and on the other hand along the auxiliary cable 21 of which the fold at contact with the cam and the follower cam is not enough to be trapped between cam 15 and the cam follower 22.

We can then in this position, by making slide the slide 7, transport the load 2 by via the suspension cable 8 in the position in desired height. Once the desired position is obtained, can be temporarily fixed, for example by a device which will be described later, the slide in position then remove the lifting cable 10 from its cooperation with the connecting rod 13. There is no longer any action from the part of the cable 10 on the cam 15. In particular, there is no more downward force acting on the connecting rod 13 of attachment. However, there is always cable 8 of suspension acting through part 19 upper of the slide, on the connecting rod 18. This connecting rod 18 will then tend to rotate the cam 15 clockwise shown in the figure under the effect of the traction exerted by the load via the suspension cable 8 on the slide so that the cam 15 will rotate one certain angle with respect to the position of figure 2, for arrive in the position of figure 4. In this position, cam 15 tends to come into contact with the cam follower 22 and wedge the auxiliary cable 21 between them, increasing the fold formed in the cable 21 at the level of the cam 15. The more the action force exerted by the cable 8 suspension will be strong, and therefore the heavier the load and the more the cam will tend to turn and deform the cable 21 auxiliary by increasing the curvature of the cable bend flexible and thus compressing it against the cam follower 22. So the bigger the load, the more the cam will deform the cable 21 and the greater the blockage, and especially the return stroke of the cam, and in particular the angle it will rotate between the position of the Figure 2 and that of FIG. 4, will be large.

Therefore, we get a system that goes allow to automatically block the slide relative to the guide rail as soon as the cable 10 is removed from the connecting rod 13, especially in the case where he breaks. However, if you wish to remove the cable 10, a fixing device must be provided temporary, in particular manual as shown in Figures 2 to 4, because the tension of cable 10 is such that it cannot just be picked up. Thus, a cam 23 is provided. also cooperating with the cam follower 22 which is articulated at a point of articulation 24. A lever 25 operated by the user allows the control, to make turn the cam to make it pass from a first position, shown in Figure 1, in which it does do not tighten the cable 21 against the cam follower 22 and therefore gives the slide the possibility of sliding along the guide rail 9 and guide cable 21, in one position, that we see in Figure 3, in which the cam 23 comes tighten the auxiliary cable 21 against the cam follower 22 so that sliding of the slide is no longer possible.

The user blocks by lever 25 the slide 7 against the auxiliary cable. He then unrolls a bit of the lifting cable 10 to relax the latter and can then unhook it from the connecting rod 13 of the slide 7, this one remaining locked in position. Once the lifting cable 10 removed, cam 15 and counter cam 22 performs a additional automatic clamping of the slide against the auxiliary cable 10, as described above.

The lifting cable 10 can then be assigned to a other decor without fear than the decor previously selected by the cable does not collapse. You can order the positioning of multiple decors with a single cable lifting and its associated motor safely.

By reversible fold is meant a fold such as when the cable is returned to its unfolded or stretched position, there is no residual deformation of the cable at the place of the fold.

Other manual systems are obviously conceivable. In particular, we could also consider a system such as those described in the prior patent previously mentioned which consists in fixing the slide to the guide rail and no longer a flexible cable.

Figures 5a, 5b, 6a and 6b show another embodiment of the invention.

As seen in Figure 5, the slide 7 is fixed to the load and to the lifting cable 10 by by means of a connecting rod 30.

A cam 35 is rotatably mounted on the slide 7 with respect to an axis 36. The slide 7 comprises also a swivel box 38 which is fixed to the slide by the axis 36 of the cam 35 and by the axis 39 of the link 30, the pivoting box being able to rotate relative to these two axes.

The connecting rod 30 includes a tube 40 indexing device in which two indexing fingers 41 can penetrate by manual pushing action of these fingers 41 inside the tube.

When you want to change the positioning decoration, we introduce the indexing fingers in the tube 40 indexing. The rotational position of the pivoting box 38 is then such that cam 35 does not jam the cable auxiliary 21 against a clamping block 42 provided in replacement of the cam follower of the embodiment described previously.

Once the decor is well positioned, we want assign the lifting cable 10 to another setting. However, given the tension of cable 10, we cannot unhook from the link 30.

So we will first perform a blocking with lifting cable 10 always hanging on the connecting rod when leaving using a small lever the indexing fingers of the indexing tube. The box swivel will then pivot and bring the cam 35 into jamming against the auxiliary cable 21. This jamming prior will then allow, by unrolling a little of the cable 10 lifting to unhook the latter from the rod 30 and to assign it to another decor.

If the lifting cable 10 breaks even though fingers are in the tube, automatic blocking will then appear, the rod 30 pivoting (in the direction of the arrow in figure 5a) under the effect of the weight of the decoration to bring the cam 35 into wedge against the cable auxiliary, according to a force proportional to the load of the decor.

There is thus, according to one embodiment, a first preliminary blocking, thanks to the actuation of the fingers indexing device that is taken out of the indexing tube to allow the lifting cable to be removed to assign it to a other decor and in addition an automatic blocking which appears in the absence of the lifting cable and which is proportional to the weight of the decor and which takes place as well with the fingers in the tube only with your fingers out of the tube.

Claims (10)

1. A lifting and positioning device for scenery or accessory in a theatre, the scenery being suspended from a suspension cable (8) fixed to a casing (7), the casing (7) incorporating a detachable means of fastening a lifting cable (10) through which the height at which the scenery is positioned is controlled, comprising
      an auxiliary cable (21), a permanent feature of the theatre, in particular, being fixed at both ends.
      automatic means of wedging, intended to wedge the casing (7) to the auxiliary cable (10) by a force even greater than the weight of the scenery, whereby
      provision has been made for the device to incorporate preliminary wedging systems, n otably manual, intended to wedge the casing (7) to the auxiliary cable (21) to allow the cable (10) to be withdrawn from the detachable means of fastening.
2. A device according to claim 1 whereby the preliminary wedging systems consist of a lever (25), a cam (23) and a contra-cam (22), the lever (25) activating the cam (23) in order to wedge the auxiliary cable (21) between the auxiliary cam (23) and the contra-cam (22).
3. A device according to claim 1, whereby the preliminary wedging systems consist of a cam (35), a pivoting box, an index tube and index fingers, the index tube being formed in a small connecting rod (30) and the pivoting box so that when the fingers are inserted in the tube, the box is wedged and keeps the cam (35) away from the auxiliary cable and when the fingers have exited the tube the box swivels and causes the cam to be wedged against the auxiliary cable, and the automatic wedging methods consist of the small connecting rod (30) and the cam (35), the box (38) in the absence of the lifting cable, either because it has been taken out or because it is broken, notably towards an upright position, causes the cam (35) to be wedged against the auxiliary cable.
4. A device according to claim 1 or 2, whereby the automatic wedging methods incorporate a cam (15) and a contra-cam (22) mounted on the casing, the cam wedging the auxiliary cable against the contra-cam.
5. A device according to claim 4, whereby the cam rotates on the casing (7) whilst the contra-cam (22) is fixed on the casing (7).
6. A device according to one of the previous claims, whereby the automatic wedging methods are arranged in such a way as to allow the auxiliary cable (21) to be wedged by forming a sheet, preferably reversible, the sheet being even stronger than the weight of the scenery (2).
7. A device according to one of the previous claims, whereby the casing slides in a fixed guide rail.
8. A device according to claim 1 or 2, whereby provision is made for a small connecting rod (17) to be connected to the cam and fixed in relation to the suspension cable (8).
9. A device according to claim 1, 2 or 8, whereby the detachable means of fixing consist of a connecting rod connected to the cam and able to be fixed to the lifting cable (10).
10. A device according to claim 9 whereby the connecting rod and the small connecting rod, when in a un-locked position, are parallel and leaning against one another when in the locked position.

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