[0001] The present invention relates to a device for locking an object along a cable. The invention makes it possible to position the object at different positions along the cable. The invention finds particular utility in the field of sonar detection and more specifically for airborne sonar often called "dipping sonar" or "dipping sonar" in Anglo-Saxon literature. This particular field consists in immersing, from a helicopter or a drone, a sonar antenna at a desired depth.

[0002] In the context of anti-submarine warfare activities, in order to be able to detect submarines submerged in a given area, recourse is generally had to the use of sonars, in particular active sonars. In this context, the deployment of sonars from aerial platforms, helicopters or drones, proves to be particularly effective because such platforms have great mobility compared to submarines.

More specifically, helicopters are used to implement sonar transmitters and receivers connected by a cable to their platform, in other words to the helicopter. We then speak of "dipped sonars". Subsequently, the sub-assembly submerged and connected by the cable is called antenna. It includes the actual sonar transmitters and receivers and possibly electronic equipment associated with the transmitters and receivers. It may also include environment sensors.

More generally, the invention relates to any object that one wishes to move and immobilize along a cable, the cable being attached to a fixed point, for example to a carrier. The cable can extend in any direction. In particular, the cable can extend horizontally and the object can be hung by gravity from the cable. The object can evolve in any environment, in particular in the air or in the water.

[0005] To return to dipped sonars, in a known manner, the launching from the platform, the immersion control as well as the recovery on board of these antennas are carried out by means of a winch located inside the helicopter. The cable is fixed to the antenna and the adjustment of the depth of immersion is achieved by winding or unwinding the cable from the helicopter.

[0006] During the descent and the ascent of the antenna by means of the winch, the cable generates significant drag in the water. This drag increases with the depth reached by the antenna due to the length of cable unwound. The rate of descent and ascent of the antenna is thus limited by the drag generated by the movement of the cable. The greater the depth, the more the speed must be reduced in descent because the antenna is dragged down only by its reduced weight of its own drag and that of the cable. On ascent, the winch must exert on the cable a force equal to the weight of the antenna increased by the overall drag. It would be possible to provide a winch capable of withstanding significant drag. The cable must be sized to withstand the pulling force exerted by the winch.

[0007] In order to limit the drag of the cable during its movements in the water, the applicant has explored the possibility of placing the winch inside the antenna. The problem then arises of locking the position of the antenna along the cable. The winch disposed inside the antenna can easily perform this function by means of a brake making it possible to block the actuator of the winch. The use of the winch actuator to ensure the locking of the position of the antenna along the cable can be complicated to implement and it may be preferable to dissociate the locking of the position of the antenna along the winch cable and actuator.

[0008] To this end, the invention proposes a clamp which is very simple to implement. In an open position of the clamp, the cable passes through it. In a closed position of the clamp, the latter blocks the circulation of the cable.

[0009] More specifically, the subject of the invention is a device for locking an object which can slide along a cable, the device comprising the cable and a clamp, the cable passing through the clamp while extending along an axis , the clamp comprising: a fixed part connected to the object by a connection with at least one degree of freedom in translation along the axis, a ring comprising an elastic material with fluid behavior, the ring comprising a central recess through which the cable, an actuator configured to compress the ring between two shapes, in a first shape, called an open shape, the cable being able to circulate freely in the central recess and in a second shape, called a closed shape, the cable being compressed by the ring.

The fixed part of the clamp is advantageously connected to the object by means of at least one elastic element.

[0011] The elastic element is advantageously configured to allow flexibility of the fixed part with respect to the object in translation along the axis and also according to the other degrees of freedom.

[0012] The elastic element is advantageously configured to transform a major part of the kinetic energy of the object into potential energy in the deformation of the spring.

[0013] The elastic element advantageously has damping properties making it possible to dissipate the potential energy resulting from the kinetic energy of the object.

The actuator exerts on the ring a force advantageously oriented along the axis of the cable.

[0015] The device may comprise a rigid washer integral with the fixed part and traversed by the cable, the ring resting against one face of the washer, the face being perpendicular to the axis of the cable, the ring being compressed between washer and actuator.

[0016] The face of the washer is called the first face. The puck has a second face opposite the first face. The second face is advantageously chamfered around a hole in the washer through which the cable passes.

[0017] Advantageously, the actuator moves the ring along the axis of the cable in the direction of the washer to reach the closed shape and in the direction opposite to the washer to reach the open shape.

[0018] The actuator advantageously comprises a screw-nut system, a fixed part of which is integral with the fixed part of the gripper and a movable part of which is configured to compress the ring.

The locking device advantageously comprises a rigid tube extending along the axis of the cable, the ring being arranged inside the tube, the tube making it possible to limit the expansion of the ring radially around the axis of the cable.

[0020] The tube is advantageously integral with the washer.

[0021] The washer is called the first washer. The device advantageously comprises a second washer through which the cable passes and interposed between the actuator and the ring.

[0022] The two washers have holes centered around the axis and through which the cable passes. In its open form, the central recess advantageously has a section perpendicular to the constant axis along the axis, the sections of the holes advantageously having smaller dimensions than those of the section of the central recess.

The invention will be better understood and other advantages will appear on reading the detailed description of an embodiment given by way of example, description illustrated by the attached drawing in which:

Figures 1a and 1b show different carriers each equipped with a dipped sonar;

[0025] Figure 2 shows a first embodiment of an antenna of the dipped sonar of Figures 1a and 1b;

Figures 3a and 3b show a second alternative embodiment of an antenna of the dipped sonar of Figures 1a and 1b;

[0027] Figures 4a and 4b describe a first embodiment of a clamp for locking the position of the sonar antenna along a cable;

[0028] Figures 5a and 5b describe a second alternative embodiment of the clamp;

[0029] Figures 6a, 6b and 6c illustrate a clamp variant.

[0030] For the sake of clarity, the same elements will bear the same references in the various figures.

[0031] La description détaillée de l’invention est faite en rapport à un sonar trempé et plus précisément à une antenne sonar pendue à un câble fixé à un porteur. L’invention n’est pas limitée à un sonar et peut être mise en œuvre pour tout objet pouvant coulisser le long du câble et dont on souhaite verrouiller la position par rapport au câble.

[0032] La figure 1a représente un drone 10 en vol stationnaire au-dessus de l’eau dont la surface porte le repère 11. Le drone 10 est équipé d’un sonar actif trempé comprenant une antenne 12 accrochée au drone 10 par un câble 14. Ce type de sonar permet notamment la détection et la classification d’objets sous-marins. La figure 1 b représente un hélicoptère 16 également équipé d’un sonar actif trempé comprenant l’antenne 12 accrochée à l’hélicoptère 16 par le câble 14. Tout type de porteur susceptible de se positionner au-dessus de l’eau peut être équipé d’un sonar actif trempé. Le porteur est apte à descendre l’antenne à une profondeur d’immersion souhaitée, à piloter une phase de détection acoustique et à remonter l’antenne afin de terminer sa mission ou afin de réaliser d’autres missions.

[0033] La figure 2 représente une première variante de réalisation d’antenne 20 d’un sonar actif trempé. L’antenne 20 est équipée d’émetteurs acoustiques 22, de récepteurs acoustiques 24 ainsi que d’un treuil motorisé 26. Le treuil 26 permet d’enrouler et de dérouler le câble 14. Une extrémité libre 27 du câble 14 permet d’accrocher l’antenne 20 au porteur tel que le drone 10 ou l’hélicoptère 16. L’antenne 20 s’étend selon un axe 28 qui est vertical lorsque l’antenne 20 est pendue par le câble 14 et n’est soumise qu’à la gravité. L’antenne 20 a une forme sensiblement de révolution autour de l’axe 28. Les émetteurs acoustiques 22 et les récepteurs acoustiques 24 sont disposés radialement autour de l’axe 28.

[0034] Les émetteurs acoustiques 22 et les récepteurs acoustiques 24 peuvent être fixés à un boîtier 29 de l’antenne 20. Les émetteurs acoustiques 22 et les récepteurs acoustiques 24 peuvent être disposés dans des zones distinctes de l’antenne 20, les zones étant superposées l’une au-dessus de l’autre comme

représenté sur la figure 2. Alternativement, les zones peuvent être imbriquées comme par exemple décrit dans la demande de brevet publiée sous le n° WO2015/092066 et déposée au nom de la demanderesse.

The winch 26 is motorized by means of an actuator 30. More specifically, the actuator 30 makes it possible to rotate a reel 32 on which the cable 14 is wound. The actuator 30 can be an electric or hydraulic motor or more generally using any form of energy able to operate in a confined space without air renewal. It is advantageously located inside the reel 32 in order to free up space in the antenna 20. The cable 14, on its unwound part, extends along the vertical axis 28. The antenna 20 hangs under the effect of gravity. In Figure 2, the reel 32 rotates around a horizontal axis 34. Alternatively, the cable 14 can be wound around a reel with a vertical axis. A winding mechanism makes it possible to store the cable 14 on the reel 32. The winding mechanism ensures alternate translation of a cable guide along the axis of the reel in order to store the cable 14 in successive layers on the reel 32. In the case of a reel with a vertical axis, the reel can be stationary and the winding mechanism then rotates around the reel in addition to its translation. Such mechanisms exist in particular in fishing reels. Alternatively, the reel can turn around its axis and the guide of the winding mechanism only moves in translation relative to a housing 29 of the antenna 20. Such mechanisms exist in particular in fishing reels. Alternatively, the reel can turn around its axis and the guide of the winding mechanism only moves in translation relative to a housing 29 of the antenna 20. Such mechanisms exist in particular in fishing reels. Alternatively, the reel can turn around its axis and the guide of the winding mechanism only moves in translation relative to a housing 29 of the antenna 20.

The winch 26 formed of the reel 32 and the actuator 30 is arranged inside the antenna 20, for example in an internal volume 36 located between the acoustic receivers 24.

The antenna 20 also comprises electronic modules 38 allowing in particular the generation of the acoustic signals emitted by the transmitters 22, the processing of the acoustic signals received by the receivers 24 and the control of the actuator 30.

The electrical energy necessary for the operation of all the components of the antenna 20 can come from the carrier and be conveyed by the cable 14. However, this solution requires increasing the section of the cable 14 to be able to convey all the energy needed. In particular, the supply of acoustic transmitters requires a high instantaneous power which can be of the order of several kilowatts. Since the cable 14 can exceed several hundred meters in length, it is then necessary to provide a sufficiently large section of cable to limit the effects of ohmic losses along the cable 14. This tends to increase the dimensions of the reel 32 which must be able to accommodate the cable 14 in almost its entire length. In addition, during the acoustic emission phases,

To limit the periods of high power transfer in the cable 14, it is advantageous that the antenna 20 is equipped with a battery 40 advantageously disposed in a lower part of the antenna 20 or at least under the volume 36 containing the winch 26 in order to allow the antenna to maintain a better vertical orientation, in particular during the descent when it is hung by the cable 14. The battery 40 can be intended to smooth the transfer of electrical energy in the cable 14, which makes it possible to reduce the section of the electrical conductors of the cable 14. To this end, the battery 40 can supply the acoustic transmitters 22 which usually emit at high power during a small fraction of the duration of a mission. It is also advantageous to completely dispense with energy transfer in the cable 14. The battery 40 then supplies all the electrical loads of the antenna, such as in particular the winch 26, the electronic modules 38, the transmitters 22 and acoustic receivers 24. For recharging the battery 40, the antenna comprises independent recharging means of the cable 14, such as for example a specific connector or a contactless recharging zone 42, for example by induction. The recharging of the battery 40 can be done on board the carrier 10 or 16 by connecting the specific connector or by placing the zone 42 close to a dedicated inductor. the antenna comprises recharging means independent of the cable 14, such as for example a specific connector or a contactless recharging zone 42, for example by induction. The recharging of the battery 40 can be done on board the carrier 10 or 16 by connecting the specific connector or by placing the zone 42 close to a dedicated inductor. the antenna comprises recharging means independent of the cable 14, such as for example a specific connector or a contactless recharging zone 42, for example by induction. The recharging of the battery 40 can be done on board the carrier 10 or 16 by connecting the specific connector or by placing the zone 42 close to a dedicated inductor.

The antenna 20 can also include environmental sensors such as a depth sounder 44 for determining the distance from the antenna 20 to the bottom and a temperature sensor 46 for measuring changes in water temperature. depending on the depth reached by the antenna 20. In fact, the propagation of the sound waves in the water is a function of the evolution of the temperature of the water. These sensors can also be powered by battery 40.

Figures 3a and 3b show a second antenna embodiment 50 of a dipped active sonar according to the invention. In this variant during sonar reception, the acoustic receivers 24, possibly placed on arms, are deployed at a distance from the housing 29 of the antenna 50. On the other hand, when the winch 26 is operated, the acoustic receivers 24 are placed against the housing 29 in order to limit the drag of the antenna 50 during the descent and the ascent of the antenna 50 in the water. This type of deployable antenna was developed in the past by the applicant. In this type of antenna, the deployment of the acoustic receivers is carried out by means of an electromechanical mechanism placed in the antenna. This mechanism includes an electric motor moving arms supporting the acoustic receivers. The motor is activated both during deployment and during folding of the arms. This mechanism is heavy and bulky.

[0042] It is possible to keep such an electromechanical mechanism for operating the arm supporting the acoustic receivers 24 in the antenna. Alternatively, the second variant makes it possible to dispense with this mechanism.

The antenna 50 comprises deployable arms 52 on which the acoustic receivers 24 are arranged. The arms 52 are advantageously distributed evenly around the axis 28 in order to ensure complete acoustic detection around the axis 28 Figure 3a partially shows the antenna 50 in which the arms 52 are folded against the housing 29. Figure 3b also partially shows the antenna 50 in which the arms 52 are deployed at a distance from the housing 29. The arms 52 are articulated with respect to the housing 29 and with respect to a body 54 forming a cover in the form of a washer and mobile in translation with respect to the housing 29 along the axis 28. The body 54 is for example of revolution around the axis 28 and the cable 14 passes through body 54 through the hole in the washer.

[0044] This double articulation allows the arms 52 to move away from or approach the housing 29 when the body 54 moves. More specifically, in the position of the body 54 shown in FIG. 3a, the arms 52 are folded housing 29 and in the position of the body 54 shown in Figure 3b, the arms 52 are deployed away from the housing 29.

The arms 52 can be articulated directly on the housing 29 and on the body 54 by means of pivot links. Once deployed, the arms 52 extend horizontally or inclined with respect to the axis 28. The kinematics of this type of mechanism is very simple. It is used in particular in sonar buoys where the wearer floats on the surface of the water. However, this orientation of the arms can degrade the acoustic detection when the wearer is a drone or a helicopter. Indeed, in this orientation, the acoustic receivers 24 are disturbed by the noise generated by the wearer. It may therefore be preferable to provide a vertical orientation of the arms 52 when they are deployed. In other words, it may be desirable to keep the arms parallel to the axis 28 during the translation of the body 54. To do this, the arms 52 can be articulated via a deformable parallelogram. More specifically, two bars 56 and 58 having parallel sections are articulated on the one hand on an arm 52, respectively by means of links 60 and 62, and on the other hand on the housing 29, respectively by means of links 64 and 66 One of the bars, the bar 58 in the example shown, is articulated to the body 54 by means of the link 68 at a point distant from its articulation to the arm 52 and from its articulation to the housing 29. Thus, when the body 54 is moves in translation, the bar 58 pivots around its articulation to the casing 29 and drives the arm 52. The bar 56 is driven by the arm 52 and also pivots with respect to the casing 29. During this movement, the orientation of the arm 52 relative to the housing 29 does not vary.

[0046] Le déplacement du corps 54 en translation par rapport au boîtier 29 peut être réalisé au moyen d’un actionneur électromécanique assurant directement ce

déplacement. L’actionneur est par exemple formé d’un vérin linéaire dont le corps est fixé au boîtier 29 et dont la tige, se déplaçant en translation par rapport au corps du vérin, est fixée au corps 54. Le montage inverse est également possible.

[0047] Avantageusement, il est possible de se passer d’actionneur entre le boîtier 29 et le corps 54 en utilisant les forces de gravité s’exerçant sur le boîtier 29 et sur le corps 54. En effet, le boîtier 29 peut contenir des composants lourds qui peuvent être mis à profit pour le déploiement des bras 52. Pour ce faire, le corps 54 est muni d’une pince 70 configurée pour pincer le câble 14 et l’immobiliser par rapport au corps 54.

In the open position of the clamp 70, the cable 14 is free relative to the body 54 and its weight, associated with that of the arms 52 via the joint 68, drives the body 54 downwards, c 'that is to say towards the housing 29. In this position, the arms 52 are also driven downwards, that is to say in the folded position against the housing 29. This position, clamp open, is shown on the Figure 3a.

In the closed position of the clamp 70 the cable 14 is immobilized with respect to the body 54. In this position, it is possible to maneuver the winch 26 so as to unwind the cable and thus allow the housing 29 and the equipment which are fixed to descend relative to the body 54 under the effect of gravity. This relative movement of the body 54 relative to the housing 29 causes the deployment of the arms 52 to reach the position of FIG. 3b. This is possible if the arms 52, and if necessary the bars 56 and 58, are lighter than the housing 29 and all the components attached to it. This condition is generally easily met due to the presence of heavy components in the housing 29, in particular the battery 40 and the winch 26.

The clamp 70 can be implemented with the antenna 20 described in FIG. 2, that is to say without a deployable arm.

Figures 4a and 4b show a first embodiment of the clamp 70 forming a device for locking the antenna 20 or 50 along the cable 14. As indicated above, the invention can be implemented for any object that can slide along a cable passing through the clamp 70 and whose position is desired to be locked relative to the cable 14. The clamp 70 can be implemented for any orientation of the cable 14. It is not necessary that the cable 14 remains vertical to implement the clamp 70.

The clamp 70 comprises a fixed part which can form part of the body 54 or be attached to the body 54 and secured thereto. As indicated above, the clamp 70 can be implemented in the antenna 20. The fixed part of the clamp is then integral with the housing 29. To simplify the rest of the description, it is considered that the fixed part of the clamp 70 is the body 54. The clip 70 further comprises a ring 72 comprising an elastic material with fluid behavior. It may be a one-piece material, for example based on rubber or silicone. Alternatively, the ring 72 can comprise an elastic envelope containing a fluid. The one-piece material makes it possible to implement a quasi-solid material whose shape holds when no mechanical stress is applied to the material. The implementation of an envelope makes it possible to implement a much more fluid material, for example liquid. The envelope can ensure the elastic behavior of the ring 72. With or without an envelope, in the absence of mechanical stress, the ring 72 has a solid shape surrounding a central recess 74 through which the cable 14 passes.

The clamp 70 also includes an actuator 76 configured to compress the ring 72 between two shapes. A first form, called open form, is shown in Figure 4a. The first shape makes it possible to obtain the open position of the clamp 70. In this first shape of the ring 72, the actuator 76 does not compress the ring 72 which retains its natural shape in which the cable 14 can circulate freely in the central recess 74. Alternatively,

in the first form of the ring 72, the actuator 76 can already apply to the ring 72 a preload, for example to hold the ring 72 in place. Even in the presence of this prestress, the cable 14 can circulate freely in the central recess 74.

In a second form of the ring 72, called closed form and shown in Figure 4b, the cable 14 is compressed by the ring 72. In other words, the central recess 74 tightens under the effect of the actuator 76 to compress the cable 14 and prevent its movement in the clamp 70. The position of the body 54 and therefore of the antenna is thus locked. The second form makes it possible to obtain the closed position of the clamp 70.

The presence of a material with fluid behavior in the ring 72 allows the central recess 74 to perfectly match the shape of the cable 14 over its entire outer surface held by the clamp 70. Such a clamp can accommodate uneven cable along its length. Irregularities can have all kinds of causes. They can be involuntary and for example be due to manufacturing imperfections, to deformations caused during the use of the antenna. Imperfections can be intentional and defined during cable design.

The clamp 70, and in particular the ring 72 and the actuator 76, are configured so that the ring 72 retains its elastic behavior, that is to say without permanent deformation, between its two forms. More precisely, from the closed shape, when the actuator 76 releases its compression, the elastic behavior of the ring 72 allows it to regain its open shape.

In the variant shown in Figures 4a and 4b, the actuator 76 exerts a radial force on the ring 72 in the direction of the axis 28 to move the ring 72 from its first shape of Figure 4a to its second form of Figure 4b.

To apply a radial force to the ring 72, in the variant of Figures 4a and 4b, the actuator 76 comprises for example a helical spring 78 extending along the axis 28 fixed at one of its ends . A motor or jack 80 is configured to pull on the second end of spring 78 to tighten it around pin 28.

[0058] Les figures 5a et 5b représentent une seconde variante de réalisation de la pince portant ici le repère 90. On retrouve dans cette variante l’anneau 72 pouvant prendre ses deux formes, la forme ouverte, représentée sur la figure 5a et laissant circuler librement le câble 14 au travers de la pince 90 et la forme fermée, représentée sur la figure 5b et compressant le câble 14 en l’empêchant de circuler dans la pince 90. A la différence de la pince 70, la pince 90 comprend un actionneur 92 exerçant un effort axial, selon l’axe 28, sur l’anneau 72 tendant à réduire la longueur de l’anneau 72 selon l’axe 28 pour atteindre sa forme fermée. En relâchant l’effort exercé par l’actionneur 92, du fait de l’élasticité de l’anneau 72, sa longueur augmente et l’anneau 72 reprend forme ouverte.

[0059] En mettant en œuvre un matériau sensiblement incompressible, tel que par exemple le caoutchouc, dont le coefficient de Poisson est proche de 0,5, la réduction de hauteur de l’anneau 72 se traduit intégralement par une augmentation de la section de l’anneau 72 perpendiculairement à l’axe 28. Cette augmentation de section entraîne une réduction de la section de l’évidement central 74 et donc une compression du câble 14. Il est possible de mettre en œuvre des matériaux dont le coefficient de Poisson est inférieur à 0,5. Il est alors nécessaire que l’actionneur 92 génère un déplacement plus important pour obtenir la même réduction de section de l’évidement central 74 qu’avec un matériau incompressible. Autrement dit, plus le coefficient de Poisson est grand, donc proche de 0,5, meilleure est le rendement de l’actionneur 92.

[0060] L’actionneur 92 peut exercer son effort de part et d’autre de l’anneau 72.

Cependant cette disposition de l’actionneur 92 peut être difficile à mettre en œuvre du fait de la hauteur de l’anneau 72 le long de l’axe 28. Il est avantageux que l’anneau 72 prenne appui contre le corps 54 et que l’actionneur 92 exerce son effort sur l’anneau 72 à l’opposé de cet appui sur le corps 54. De plus, il est avantageux que l’appui de l’anneau 72 sur le corps 54 se fasse de façon répartie autour de l’axe 28 du câble 14. A cet effet, la pince 90 comprend une rondelle 94 rigide solidaire du corps 54 et traversée par le câble 14. L’anneau 72 prend appui contre une face 96 de la rondelle 94 perpendiculaire à l’axe 28 du câble 14. L’anneau 72 est compressé entre la rondelle 94 et l’actionneur 92.

[0061] La rondelle 94 peut permettre de guider le câble 14 en entrée de la pince 90.

For this purpose, the washer 94 has a chamfer 98 made in a face 100 of the washer 94 opposite the face 96. The chamfer 98 is made around the bore 102 of the washer 94. The bore 102 is used for the passage of the cable 14 through the washer 94. The bore 102 and the central recess 74 of the ring 72 are arranged in the extension of one another. More specifically, the bore 102 and the central recess 74 are both concentric with the axis 28. In a plane perpendicular to the axis 28, the section of the central recess 74 is constant over the entire height of the ring 72. The bore section 102 may have the same dimensions as the central recess section 74 in the open ring shape 72 shown in Figure 5a.

[0062] In addition to guiding the cable 14, the washer 94 can limit the friction of the cable 14 circulating in the central recess 74 when the ring 72 is in its open form. For this purpose, the section of the bore 102 has dimensions smaller than those of the section of the central recess 74 in the open form. Thus, in the open shape of the ring 72, the cable 14 will come into contact with the washer 94 without touching the ring 72 in the vicinity of the washer 94. It will be possible to choose for the washer 94, a material having a coefficient of friction with the cable 14 lower than the coefficient of friction between the ring 72 and the cable. For this purpose, the washer 94 can for example be made of bronze.

[0063] It is advantageous that the support of the actuator 92 on the ring 72 is done in a distributed manner around the axis 28 of the cable 14. For this purpose, the clamp 90 comprises a second washer 104 movable in translation along the axis 28. The translational mobility of the washer 104 allows the ring 72 to pass from its open shape to its closed shape and vice versa. The washer 104 includes a bore 106 through which the cable 14 passes. The washer 104 can have the same shape as that of the washer 94, in particular with its chamfer. The ring 72 is arranged between the washers 94 and 104. The two washers 94 and 104 are mounted oppositely. The actuator 92 exerts its force on the ring 72 via the washer 104. By defining sections of the holes 102 and 106 having for both, dimensions smaller than those of the section of the central recess 74 in its open form, the cable 14, when it is stretched, touches only the bores 102 and 106 and not the ring 72, thus eliminating any friction between the cable 14 and ring 72 in its open form. As for

the washer 94, the material of the washer 104 is chosen to limit the friction forces with the cable 14.

[0064] The actuator 92 can take many forms such as for example a linear cylinder exerting its force on the washer 104 when it is present, or directly on the ring 72 in the absence of washer 104. Alternatively, in order to to simplify clamp 90, actuator 92 comprises a screw-nut system, a fixed part of which is integral with body 54 and a movable part of which is intended to compress ring 72. The configuration of the screw-nut system shown in FIGS. 5a and 5b ensure good compactness of the screw nut system. More specifically, a concentric thread 108 of the axis 28 is made in the body 54. A screw 110 cooperates with the thread 108, moves along the axis 28 and presses the washer 104 in the direction of the washer 94 to pass from the open shape to the closed shape of the ring 72 and in the opposite direction to return to the open shape. The screw 110 is pierced along the axis 28 to allow the passage of the cable 14.

[0065] By compressing the ring 72 between the washer 94 and the actuator 92, the ring 72 increases its section both to reduce the dimensions of the central recess 74 and to increase the dimensions of the outer section of the ring 72 which deforms into a barrel. Reducing the section of the central recess is useful for compressing the cable 14. However, the swelling of the outside of the ring 72 is unnecessary to ensure the pinching of the cable 14. It is advantageous to avoid this swelling by having the ring 72 inside a rigid tube 112 making it possible to limit the expansion of the ring 72 radially around the axis 28. The tube 112 has an internal section whose dimensions are the same, at the functional clearances near, than the dimensions of the outer section of the ring 72 in its open form.

In both variants, the clamp comprises a single actuator, respectively 76 and 92, making it possible to compress the ring 72. It is also possible to implement several possibly independent actuators.

In Figures 4a and 4b, the body 54 forms the fixed part of the clamp 70. Similarly in Figures 5a and 5b, the tube 112 forms the fixed part of the clamp 90. The fixed part of the clamp can be integral with the antenna 20 or 50. Alternatively, the fixed part of the clamp can be floating relative to the antenna 20 or 50. In the open position of the clamp, the fixed part can retain at least one degree of freedom in translation along the axis 28 relative to the antenna 20 or 50. This degree of freedom facilitates the closing of the clamp 70 or 90 when the antenna is descending or ascending. This degree of freedom makes it possible to limit the friction of the ring 72 on the cable 14 when closing the clamp.

More specifically, in Figures 6a, 6b and 6c, the tube 112 is connected to the body 54 by allowing a translational movement along the axis 28 between the body 54 and the tube 112. A spring 114 connects the tube 112 to the body 54. The spring 114 can be compressed by bringing the tube 112 closer to the body 54. In FIG. 6a, the clamp 90 is in the open position. The tube 112 is located under the body 54 at a distance from the body 54. The cable 14 can circulate freely in the central recess 74 of the ring 72. FIG. 6b represents the beginning of the closing of the clamp 90. More precisely the actuator 92 compresses ring 72 to bring it into pressure against cable 14. At the start of tightening, spring 114 still remains relaxed as in FIG. 6a. Then, as shown in Figure 6c,

The spring 114 allows flexibility of the tube 112 relative to the body 54 in translation along the axis 28 and also according to the other degrees of freedom. This can improve the centering of the cable 14 crossing the gripper 90. In other words, in addition to the degree of freedom in translation along the axis 28, the other degrees of freedom can have an advantage. Alternatively to the presence of the spring 114, any other slide along the axis 28 allowing a translational movement of the tube 112 relative to the body 54 can be implemented. This translation

makes it possible to limit the slippage of the cable 14 in the central recess 74 of the ring 72 when the clamp 90 is closed. More specifically, it may be desirable to tighten the clamp 90 while the antenna is descending. With a clamp 90 whose fixed part, in this case the tube 112, is integral with the body 54 when the clamp 90 is tightened, the antenna loses speed and the clamp 90 acts as a brake by rubbing on the cable 14. All of the kinetic energy of the antenna is dissipated by this friction, which leads to wear of the cable 14 and of the ring 72. On the contrary, with a degree of freedom of the clamp 90 in translation according to the axis 28 with respect to the body 54, only the kinetic energy due to the mass of the clamp is dissipated by friction on the cable 14. The clamp 90 having a mass much lower than that of the entire antenna, and at most less than half the mass of the antenna, the major part of the kinetic energy of the antenna is transformed into energy. potential in the compression of the spring 114, which therefore limits the energy dissipated by friction between the ring 72 and the cable 14 and therefore the wear thereof. The compression of the spring 114 to limit the friction on the cable works both on the descent and the ascent of the antenna 50. In the example shown in Figures 6a, 6b and 6c the spring 114 compresses during tightening of the clamp 90. Alternatively, it is possible to provide a spring which is tensioned when the clamp 90 is tightened. The bottom of the tube 112 is then fixed to a spring which is itself fixed to the body 54, located this time under the tubing 112.

The spring 114 can be replaced by other types of elastic elements such as elastomers. The elastic element may have damping properties making it possible to dissipate the potential energy resulting from the kinetic energy of the gripper. It is for example possible to implement a damper instead of or in addition to the spring 114. Some elastomers also have damping properties in addition to their elastic property.

The assembly described using Figures 6a to 6c can of course be implemented for the clamp 70 and more generally for any clamp within the scope of the invention.

CLAIMS

1. Device for locking an object (20; 50) slidable along a cable (14), the device comprising the cable (14) and a clamp (70; 90), the cable (14) passing through the gripper (70; 90) extending along an axis (28), the gripper (70) comprising: a fixed part (112) connected to the object (20; 50) by a connection (114) to at least one degree of freedom in translation along the axis (28), a ring (72) comprising an elastic material with fluid behavior, the ring (72) comprising a central recess (74) through which the cable (14) passes, an actuator ( 76; 92) configured to compress the ring (72) between two forms, in a first form, called open form, the cable (14) being able to circulate freely in the central recess (74) and in a second form, called closed, the cable (14) being compressed by the ring (72).

2. Locking device according to claim 1, wherein the fixed part (112) of the clamp (70; 90) is connected to the object (20; 50) by means of at least one elastic element (114).

3. Locking device according to claim 2, wherein the elastic element (114) is configured to allow flexibility of the fixed part (112) relative to the object (50) in translation along the axis (28) and also according to the other degrees of freedom.

4. Locking device according to one of Claims 2 or 3, in which the elastic element (114) is configured to transform a major part of the kinetic energy of the object (50) into potential energy in the deformation of the elastic element (114).

5. Locking device according to one of claims 2 to 4, wherein the elastic element (114) has damping properties making it possible to dissipate the potential energy resulting from the kinetic energy of the object (50) .

6. Locking device according to one of the preceding claims, wherein the actuator (92) exerts on the ring (72) an axial force along the axis (28) of the cable (14).

7. Locking device according to claim 6, comprising a rigid washer (94) integral with the fixed part (112) and traversed by the cable (14), the ring (72) resting against a face (96) of the washer (94), the face (96) being perpendicular to the axis (28) of the cable (14), the ring (72) being compressed between the washer (94) and the actuator (92).

8. Locking device according to claim 7, in which the face (96) of the washer (94) is called the first face, in which the washer (94) has a second face (100) opposite the first face (96). and in which the second face (100) is chamfered around a bore (102) of the washer (94) through which the cable (14) passes.

9. Locking device according to one of claims 7 or 8, wherein the actuator (92) moves the ring along the axis (28) of the cable (14), in the direction of the washer (94) to reach the closed shape and away from the washer (94) to reach the open shape.

10. Locking device according to claim 9, wherein the actuator (92) comprises a screw-nut system (108, 110) of which a fixed part (108) is integral with the fixed part (112) of the clamp (90) and of which a mobile part (110) is configured to compress the ring (72).

11. Locking device according to one of claims 6 to 10, comprising a rigid tube (112) extending along the axis (28) of the cable (14), the ring (72) being disposed inside of the tube (112), the tube (112) making it possible to limit the expansion of the ring (72) radially around the axis (28) of the cable (14).

12. Locking device according to claim 11, wherein the tube (112) is integral with the washer (94).

13. Locking device according to one of claims 7 to 12 as a dependent claim of claim 7, wherein the washer (94) is called first washer (94), the device comprising a second washer (104) through which the cable (14) and interposed between the actuator (92) and the ring (72).

14. Locking device according to claim 13, in which the two washers (94, 104) have holes (102, 106) centered around the axis (28) and traversed by the cable (14), in which, in its open shape, the central recess (74) has a section perpendicular to the axis (28) which is constant along the axis (28) and in which the sections of the bores (102, 106) have smaller dimensions than those of the central recess (74) section.