Equipment for applying a self-tightening clamp to an overhead line cable of a power line

Abstract

An equipment for attaching a self-tightening clamp (300) to an overhead line cable of a power line (400), such as a conductor or shield wire, comprises a transport robot (100), with a chassis (110) and a set of wheels (120) to remain suspended from a cable (400) and move along the cable (400). The equipment also comprises a handling system (200) having a support (210), to support a first jaw (310) of a self-tightening clamp (300), and a clamping member (220) configured to engage a transmission element (331) of the clamp (300) connecting the first and second jaws (310, 320). The clamping member (220) is movable so that the first and second jaws (310, 320) of the clamp (300) are clamped onto the cable (400).

Description

[0001] Title: “Equipment for applying a self-tightening clamp to an overhead line cable of a power line”.

[0002] DESCRIPTION

[0003] Technical field

[0004] The present invention is developed in the technical field of overhead power line maintenance. In particular, the invention concerns a piece of equipment for attaching a self-tightening clamp to a cable for an overhead line of a power line.

[0005] State of the art

[0006] Maintenance work on overhead lines usually requires a significant commitment of personnel and the adoption of various safety measures, both from the point of view of the electrical risk and the height at which the power line conductors are located. In fact, one or more operators often have to climb a pylon to reach the conductors, and then move along the conductors suspended from them, while carrying the necessary maintenance equipment. Sometimes, it is also necessary to provide platforms on pylons as an intermediate location for operators during maintenance.

[0007] Robots are known in the art which, once loaded onto a power line conductor by means of cranes or drones, are able to move along the conductor. These robots can be equipped in different ways in order to perform one or more different maintenance tasks on the conductor. This reduces the amount of personnel involved in the operation, while the robot can be controlled remotely.

[0008] One of the operations that is often required during the maintenance of an overhead power line is the application of a self-tightening clamp on the conductor. The clamp in turn is secured to a traction cable, which allows the conductor to be pulled in the desired direction. In some cases, the traction of the clamp serves to reduce the mechanical stress on a portion of the conductor. For this purpose, for example, the clamp can be pulled towards a nearby pylon. In other situations, the clamp can be pulled towards the ground to make the cable more accessible.

[0009] Summary of the invention

[0010] The aim of the present invention is to automate the application of a selftightening clamp on an overhead cable, in order to reduce the time, personnel and safety measures required for this operation.

[0011] This and other purposes are achieved by equipment for applying a selftightening clamp to an overhead power line cable, and by a system for maintaining a cable, according to any one of the appended claims.

[0012] The invention provides a transport robot and a handling system for a selftightening clamp, mounted to the robot. The robot is designed to move along a cable, suspended from it, to bring the handling system to where it is needed.

[0013] The handling system comprises a support for supporting a first jaw of a selftightening clamp, a clamping member, and a set of actuators configured to move the clamping member with respect to the support. As the clamping member moves, it engages a second jaw of the clamp, or a transmission element of the clamp, and causes the first and second jaws of the self-tightening clamp to clamp onto the cable.

[0014] Advantageously, the clamp can be brought to the desired point in an automated manner, where the actuators, support and clamping member of the handling system determine the clamping of the clamp onto the cable. All this can be remotely controlled by an operator with minimal risk. A rope or chain can then be used to pull the clamp in the desired direction.

[0015] Further features and advantages of the invention will be recognisable to a person skilled in the art by the following detailed description of exemplary embodiments of the invention.

[0016] Brief description of the figures

[0017] For a better understanding of the following detailed description, some embodiments of the invention are illustrated in the accompanying drawings, wherein:

[0018] - Figure 1 shows a perspective view of a self-tightening clamp and equipment for applying the clamp to an overhead power line cable, according to an embodiment of the invention,

[0019] - Figure 2 shows a front schematic view of a transport robot of the equipment in Figure 1,

[0020] - Figure 3 shows a perspective view of a safety hook of the robot in Figure 2,

[0021] - Figure 4 shows a perspective view of the clamp in Figure 1 and a cable,

[0022] - Figure 5 shows a side view of the clamp in Figure 4,

[0023] - Figure 6 shows a perspective view of a clamp handling system, of the equipment in Figure 1, and

[0024] - Figure 7 shows a side view of the handling system in Figure 5 together with the clamp in Figure 4.

[0025] DETAILED DESCRIPTION

[0026] An object of the present invention is an equipment for attaching a self-tightening clamp to a cable 400 for an overhead power line, in particular a phase conductor or a shield wire. This equipment includes a transport robot 100 and a handling system 200 for a self-tightening clamp 300. The assembly of the robot 100, the handling system 200 and the clamp 300 will also be referred to as the cable maintenance system 400, and is a further object of the invention.

[0027] First of all, a description of the transport robot 100 is provided, of which some alternative embodiments are known in the state of the art.

[0028] The transport robot 100 comprises a chassis 110. Preferably, the chassis 110 comprises a carriage structure 111 with two end portions spaced apart in a longitudinal direction X-X, which corresponds to the direction of the cable 400 on which the robot 100 can be positioned.

[0029] In addition, the transport robot 100 comprises a set of wheels 120 mounted to the chassis 110, in particular to the carriage structure 111. The set of wheels 120 is configured to keep the chassis 110 suspended from the cable 400. In particular, the set of wheels 120 is configured to engage a cable 400 that is located along a predetermined cable axis. In addition, the set of wheels 120, together with the carriage structure 111, is movable along the cable 400 in the longitudinal direction X-X, transporting the chassis 110 along the cable 400.

[0030] Preferably, at least two wheels are spaced along the longitudinal direction X-X, for example as they are connected to the chassis 110 at the opposite end portions of the carriage structure 111.

[0031] More specifically, in the preferred embodiment, the set of wheels 120 comprises a first plurality of wheels 121, distributed along the longitudinal direction X-X and configured to engage the cable 400 from above. In addition, the set of wheels 120 comprises a second plurality of wheels 122, distributed along the longitudinal direction X-X and configured to engage the cable 400 from below. The first and second plurality of wheels 121, 122 are configured to clamp the cable 400 between them.

[0032] For example, in the embodiment illustrated, at each end of the carriage structure 111, the cable 400 is clamped from above and below by a respective wheel of the first plurality of wheels 121 and a respective wheel of the second plurality of wheels 122.

[0033] The transport robot 100 comprises a first set of actuators 130, connected to the chassis 110 and to the set of wheels 120. The first set of actuators 130 is configured at least to move the set of wheels 120 along the cable 400. In addition, the first set of actuators 130 can optionally perform other functions detailed below.

[0034] In an embodiment, in order to move the set of wheels 120, the first set of actuators 130 comprises one or more motors 131, configured to rotate one or more wheels with respect to the chassis 110 and to the cable 400. For example, a motor 131 may be coaxial to a wheel, or it may be connected to a wheel via transmission kinematics.

[0035] Several separate wheels can be driven by separate motors 131 or a common motor 131 via separate kinematics. In order for the robot 100 to move along the cable 400, it is not necessary for all the wheels to be driven by a motor 131, but there can be traction wheels, which are connected to one or more respective motors 131, and driven wheels, which rotate freely independently of the motors 131.

[0036] Preferably, the first set of actuators 130 is also configured to move the second plurality of wheels 122 towards and away from the first plurality of wheels 121, and thus from the cable 400, in such a way as to clamp the cable 400 between the first and second plurality of wheels 121, 122, and to release the cable 400, respectively.

[0037] More particularly, the second set of wheels 122 is movable along a height direction Z-Z, which is perpendicular to the longitudinal direction X-X. Preferably, the second set of wheels 122 is also movable along a lateral direction Y-Y, which is transverse (preferably perpendicular) to the longitudinal direction X-X and the height direction Z-Z. Thanks to these movements by the first set of actuators 130, the connection and disconnection of the robot 100 from the cable 400 takes place. The transport robot 100 comprises a first power supply device 140 to power the first set of actuators 120. In the preferred embodiment, the first power supply device 140 is electric, and the first set of actuators 120 comprises one or more electric actuators, such as at least one electric motor 131. The first power supply device 140 may comprise, for example, a battery and / or a supercapacitor.

[0038] In alternative embodiments, the first power supply device 140 and the first set of actuators 130 can be, for example, pneumatic or fuel -powered. Optionally, several actuators of the first set of actuators 130 may be of different types, and thus the transport robot 100 may comprise several first power supply devices 140 of different types.

[0039] Preferably, the chassis 100 comprises a platform 112 connected to the carriage structure 111. The platform 112 is preferably positioned below the carriage structure 111 and the cable axis, and can perform a balancing function for the robot 100. For this purpose, a counterweight 180 can be attached to the platform 112. Furthermore, preferably the first power supply device 140 can be placed on the platform 112, in addition to and / or instead of the counterweight 180. In addition, an electronic control unit 150 can be positioned on the platform 112.

[0040] In order to optimise the balancing of the robot 100 by compensating for movements that may be carried out by the robot 100 or other structures connected to the robot 100 for the purposes described below, preferably the first set of actuators 130 is configured to move the platform 112 with respect to the carriage structure 111, along the lateral direction Y-Y.

[0041] The control unit 150 is configured to receive control signals from a remote device (not shown), and to control the first set of actuators 130, as well as other components described below, in particular a second set of actuators.

[0042] Preferably, the robot 100 comprises a set of sensors (not shown) in signal communication with the control unit 150. The sensors can be configured to acquire data of various kinds useful for controlling the robot 100. In particular, it is preferable that the set of sensors comprises one or more video cameras, configured to frame the cable 400 and / or one or more parts of the robot 100 and other components described below. The first set of actuators 130 can be configured to change the orientation of one or more video cameras. The preferred set of sensors then comprises an anemometer, or other sensors that can be contemplated by a person skilled in the art.

[0043] From what has been described, it is recognised that, in the preferred embodiment, the first set of actuators 130 may comprise motors 131 for rotating the set of wheels 120, linear actuators 132 for moving the second plurality of wheels 122 towards and away from the cable 400, a linear actuator 133 for the motion of the platform 112, and rotational actuators (not illustrated) for the orientation of the video cameras.

[0044] Preferably, the robot 100 comprises one or more safety hooks 160 connected to the chassis 110, in particular to the carriage structure 111. Preferably, two safety hooks 160 are spaced apart in the longitudinal direction X-X. Each safety hook 160 comprises two elastically loaded jaws 161 to close around the cable 400, securing the robot 100 to the cable 400. In addition, the hook 160 comprises a system of levers 162 articulated to each other and to the jaws 161 of the hook 160. The lever system 162 is configured to open the jaws 161 when the lever system 162 is subjected to a predetermined traction, specifically traction in the height direction Z-Z.

[0045] Advantageously, the robot 100 can be gripped and lifted by the lever systems 162 of the safety hooks 160. As long as this lifting traction is applied, the jaws 161 of the hooks 160 are open and the robot 100 can be positioned on the cable 400 and removed from it. Once the robot 100 is in position, by releasing the levers 162, the jaws 161 of the hooks 160 close around the cable 400.

[0046] Lifting the robot 100 and transporting it from the ground to a cable 400, in particular a cable 400 of an overhead line, can be carried out by a crane or a drone.

[0047] The self-tightening clamp 300 that is to be attached to the cable 400 is now described. The clamp 300 will be described with reference to the position it occupies when applied to the cable 400.

[0048] The self-tightening clamp 300 comprises a first jaw 310 and a second jaw 320, spaced from the first jaw 310, preferably along the height direction Z-Z. The first jaw 310 is configured for positioning along the cable 400.

[0049] In more detail, the first jaw 310 has two end portions 311 spaced apart along the longitudinal direction X-X. In addition, the first jaw 310 has a guide 312, for example made as a slot, extending predominantly along the longitudinal direction X-X. The guide 312 is positioned at one of the end portions 311 of the first jaw 310.

[0050] The clamp 300 then comprises a set of transmission elements 330 that connect the first and second jaws 310, 320. In detail, the transmission elements 330 are configured for the movement of the second jaw 320 with respect to the first jaw 310 transversely to the longitudinal direction X-X, e.g. at least partially along the height direction Z-Z, to clamp the cable 400 between the first and second jaw 310, 320.

[0051] The transmission elements 330 are rotatably articulated to each other and preferably protrude from the first jaw 310 in a transverse direction to the longitudinal direction X-X, in particular in the height direction Z-Z.

[0052] The set of transmission elements 330 has a first end 333 hinged to the first jaw 310, and a second end 334 sliding along the guide 312 of the first jaw 310. In particular, the second end 334 comprises a slider sliding along the guide 312.

[0053] In the preferred embodiment, the set of transmission elements 330 is identified by a crank mechanism comprising a first and second transmission element 331, 332 articulated together. The first end 333 is formed in the first transmission element 331 and the second end 334 is formed in the second transmission element 332.

[0054] The second jaw 320 has only been shown in Figure 5. The second jaw 320 can be connected to, or attached to, or formed in the first transmission element 331. In this way, the movement of the second end 334 along the guide causes the rotation of the first transmission element 331 and thus the movement of the second jaw 320 towards the first jaw 310, so as to clamp the cable 400 between them.

[0055] However, it cannot be ruled out that in alternative embodiments, the second jaw 320 can be connected to, or formed in, the second transmission element 332.

[0056] The self-tightening clamp 300 comprises a coupling element 340, e.g. shaped like a hook. The coupling element 340 is configured to secure a chain or rope to the clamp 300.

[0057] The coupling element 340 is connected to the second end 334 of the set of transmission elements 330, in particular to the slider. Therefore, when the clamp 300 is secured to the cable 400, and thus the second end 334 is located along the guide 312 in a position distal from the first end 333, with the traction of the rope or chain in the appropriate direction, in particular at least partially along the longitudinal direction X- X, the second end 334 is held by the rope or chain in its position along the guide 312, reinforcing the clamping conditions on the cable 400.

[0058] The structure and operation of the 200 handling system for the 400 selftightening clamp will now be described.

[0059] The handling system 200 comprises a support 210, connected to the chassis 110 of the transport robot 100. The support 210 is configured to support the first jaw 310 of the clamp 300 so that the cable axis is between the first and second jaws 310, 320. In the illustrated embodiment, the support 210 is shaped like a bracket, and is configured to rest the first jaw 310 on it.

[0060] Preferably, for optimal handling of the clamp 300 without interfering with the robot 100, the handling system 200, and in particular the support 210, protrudes from the chassis 110 of the robot 100 in the longitudinal direction X-X.

[0061] The handling system 200 then comprises a clamping member 220 with a clamping portion 221. The clamping element 220 is movably connected to the support 210, for the purposes described below. In the illustrated embodiment, the clamping element 220 is hinged to the support 210. In addition, preferably the clamping element 220 protrudes from the support 210 in the height direction Z-Z.

[0062] Preferably, the clamping portion 221 is distanced from the support 210 in at least one direction transverse to the longitudinal direction X-X, in particular in the height direction Z-Z, and more preferably is also distanced in the longitudinal direction X-X.

[0063] In the embodiment illustrated, the clamping portion 221 of the clamping member 220 is configured to engage, in particular to grip, the first transmission element 331 of the clamp 300.

[0064] In alternative embodiments, a person skilled in the art will have no difficulty achieving the purposes illustrated below by positioning the clamping member 220 differently, such that the clamping portion 221 does not engage the first transmission element 331 of the clamp 300, but instead directly engages the second jaw 320 or any other part of the set of transmission elements 330, preferably in a position that is located, when considering the longitudinal direction X-X, between the second jaw 320 and the second end 334 of the set of transmission elements 330.

[0065] In order to maintain the correct positioning of the clamp 300 with respect to the handling system 200, preferably the handling system 200 comprises at least one gripping element 230a, 230b, configured to grip and release the self-tightening clamp 300. In the preferred embodiment, the gripping element 230a, 230b comprises a locking seat 231 and a locking member 232. The locking seat 231 is configured to receive a portion of the clamp 300, and the locking member 232 is configured to retain that portion of the clamp 300 in the locking seat 231, for example by closing access to the locking seat 231 or pressing the portion of the clamp 300 of interest into the locking seat 231.

[0066] The gripping element 230a, 230b can also be identified by a pair of jaws, which identify a seat between them, where each of the jaws retains the portion of clamp 300 in the seat against the other jaw.

[0067] Preferably the gripping element 230a, 230b is positioned at the support 210 and / or the clamping element 220. Several gripping elements 230a, 230b can be provided on these components. In the preferred embodiment, a first gripping element 230a identifies the clamping portion 221 of the clamping member 220. In addition, a second gripping element 230b is connected to the support 210 and is configured to retain the clamp 300 against the support 210, and preferably prevent them from sliding against each other in the longitudinal direction X-X.

[0068] The handling system 200 comprises a second set of actuators 240 configured at least to move the clamping member 220 with respect to the support 210. The second set of actuators 240 can also include other actuators to perform additional functions discussed below. The second set of actuators 240 can be controlled by the same remote device (not shown) that also controls the first set of actuators 130.

[0069] More specifically, the clamping member 220 is moved in such a way as to clamp the first and second jaws 310, 320 of the clamp 300 on the cable 400. For this purpose, the clamping element 220 is preferably rotated with respect to the support 210. In the embodiment illustrated, in this context the clamping portion 221 is movable with respect to the support 210 at least along the longitudinal direction X-X. In fact, with this movement the set of transmission elements 330 is configured to move the second jaw 320 towards the first jaw 310 in the height direction Z-Z.

[0070] In the preferred embodiment, in order to perform the function just described, the second set of actuators 240 comprises a cylinder-piston system 241, preferably pneumatic, having two ends constrained to the support 210 and to the clamping member 220, respectively. This cylinder-piston system 241 can be operated to be lengthened and shortened, thus determining the desired movement of the clamping member 220 with respect to the support 210.

[0071] More specifically, the shortening of the cylinder-piston system 241 causes the clamping of the jaws 310, 320 on the cable 400, while the opposite movement can release the cable 400 from the jaws 310, 320.

[0072] For the purpose of powering the second set of actuators 240, a second power supply device 170, e.g. of the pneumatic type, is preferably provided, although embodiments in which the second power supply device 170 is of other types, e.g. electric type, are not excluded.

[0073] Preferably, the second power supply device 170 is part of the robot 100 and is mounted to the chassis 110, in particular on the platform 112.

[0074] Note that the same robot 100, which according to the invention is connected to the handling system 200 to apply the clamp 300 on the cable 400, may at other times be disconnected from the handling system 200 and connected to other automated maintenance devices. Thus, the second power supply device 170 can sometimes power the second set of actuators 240 of the handling system 200, and sometimes other actuators of other maintenance devices.

[0075] In an alternative embodiment, instead of providing two separate power supply devices 140, 170 for the two separate sets of actuators 130, 240, a single power supply device may be sufficient.

[0076] Furthermore, it is not necessary that all the actuators of the first set 130 are supplied by the first power supply device 140, and all the actuators of the second set 240 are powered by the second power supply device 170, but there can also be individual actuators of the first set 130 powered by the second power supply device 170 and individual actuators of the second set 240 supplied by the first power supply device 140.

[0077] Preferably, the second set of actuators 240, in addition to moving the clamping element 220, is also configured to actuate the at least one gripping element 230a, 230b, in particular the locking member 232. For this purpose, the second set of actuators 240 can comprise, for example, a linear actuator 242 for each gripper element 230a, 230b.

[0078] In the preferred embodiment, the second set of actuators 240 is also configured to move the support 210 with respect to the chassis 110 at least in the lateral direction Y-Y, towards and away from the cable axis. In this way, the second set of actuators 240 can move the clamp 300 from a position distanced from the cable 400 to a position in which the cable 400 is between the first and second jaws 310, 320. In this position, the clamp 300 can be clamped, and the clamp 300 can be released from at least one gripping element 230a, 230b.

[0079] Subsequently, the reverse lateral movement moves the support 210 and the clamping member 220 away from the cable 400 and from the clamp 300, which is now attached to the cable 400.

[0080] In addition, the second set of actuators 240 is preferably configured to move the support 210 with respect to the chassis 110 in the height direction Z-Z. This allows the height alignment of the cable 400 with the space between the first and second jaws 310, 320, prior to positioning the clamp 300 on the cable 400. Both movements of the support 210 in the lateral direction Y-Y and in the height direction Z-Z can be achieved by means of linear actuators 243, placed between the support 210 and the chassis 110.

[0081] Therefore, the operation of the described equipment involves locking the clamp 300 to the handling system 200 by means of the at least one gripping element 230a, 230b. Then the robot 100 is transported on the cable 400. The second set of actuators 240 provides alignment between the jaws 310, 320 and the cable 400. The clamping member 220 clamps the jaws 310, 320 on the cable 400. The clamp 300 is freed from the at least one gripping element 230a, 230b. The robot 100 with the handling system 200 can be moved away from the clamp 300, to which a rope or chain can be connected.

[0082] Similar reverse movements allow the clamp 300 to be removed from the cable 400.

Claims

CLAIMS1. Equipment for applying a self-tightening clamp (300) to an overhead line cable (400) of a power line, comprising:- a transport robot (100), comprising:- a chassis (110),- a set of wheels (120) mounted to the chassis (110), the set of wheels (120) being configured to hold the chassis (110) suspended from a cable (400), and- a first set of actuators (130) connected to the chassis (110) and set of wheels (120) and configured to move the set of wheels (120) along the cable (400) in a longitudinal direction (X-X) to transport the chassis (110); and- a handling system (200) for a self-tightening clamp (300), comprising:- a support (210) connected to the chassis (110) of the transport robot (100), the support (210) being configured to support a first jaw (310) of a self-tightening clamp (300),- a clamping device (220) configured to engage a second jaw (320) of the selftightening clamp (300), or to engage a transmission element (331) of the self- tightening clamp (300) connecting the first and second jaws (310, 320), and- a second set of actuators (240) configured to move the clamping device (220) with respect to the support (210) in such a way as to clamp the first and second jaws (310, 320) of the self-tightening clamp (300) on the cable (400).

2. Equipment according to claim 1, wherein:- the clamping member (220) has a clamping portion (221), configured to engage the second jaw (320) or said transmission element (331), the clamping portion (221) beingdistanced from the support (210) in a height direction (Z-Z), perpendicular to the longitudinal direction (X-X), and- the clamping portion (221) is movable with respect to the support (210) at least along the longitudinal direction (X-X) to clamp the first and second jaws (310, 320) on the cable (400).

3. Equipment according to claim 1 or 2, wherein:- the clamping member (220) is hinged to the support (210), and- the second set of actuators (240) comprises a cylinder-piston system (241), preferably pneumatic, having two ends constrained to the support (210) and to the clamping member (220), respectively.

4. Equipment according to any one of claims 1 to 3, wherein the handling system (200) comprises at least one gripping element (230a, 230b) configured to grip and release the self-tightening clamp (300), preferably the at least one gripping element (230a, 230b) being placed at the support (210) and / or the clamping member (220).

5. Equipment according to any one of claims 1 to 4, wherein the second set of actuators (240) is further configured to move the support (210) at least in a lateral direction (Y- Y), which is transverse to the longitudinal direction (X-X), preferably wherein the support (210) is movable along the lateral direction (Y-Y) towards the cable (400), in order to bring the self-tightening clamp (300) towards the cable (400), and away from the cable (400), in order to leave the self-tightening clamp (300) attached to the cable (400).

6. Equipment according to any one of claims 1 to 5, wherein the handling system (200) protrudes from the chassis (110) in the longitudinal direction (X-X).

7. Equipment according to any one of claims 1 to 6, wherein the transport robot (100) comprises:- a power supply device (140, 170) for the first and second set of actuators (240), mounted to the chassis (110), or- a first power supply device (140), preferably electric, to power at least one actuator of the first set of actuators (130), and a second power supply device (170), preferably pneumatic, to power at least one actuator of the second set of actuators (240), the first and second power supply devices (140, 170) being mounted to the chassis (110).

8. System for the maintenance of a cable (400) for an overhead line cable of a power line, comprising:- an equipment according to any one of claims 1 to 7, and- a self-tightening clamp (300), comprising:- a first jaw (310), configured for positioning along the cable (400), and having a guide (312),- a set of transmission elements (330) rotatably articulated to each other, the set of transmission elements (330) having a first end (333) hinged to the first jaw (310), and a second end (334) sliding along the guide (312) of the first jaw (310), and- a second jaw (320), connected to the set of transmission elements (330) in such a way that it is movable with respect to the first jaw (310) transversely to the longitudinal direction (X-X) to clamp the cable (400) between the first andsecond jaw (310, 320).

9. System according to claim 8, wherein the clamping member (220) is configured to engage a transmission element (331) of the set of transmission elements (330), at a position that is located, along the longitudinal direction (X-X), between the second jaw (320) and the second end (334) of the set of transmission elements (330).

10. System according to claim 9 or 10, wherein the self-tightening clamp (300) comprises a coupling element (340) configured to secure a chain or rope to the clamp (300), the coupling element (340) being connected to the second end (334) of the set of transmission elements (330).

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