Compensation device for compensating the length of a tension cable

Abstract

A compensation device (1) for compensating for the length of a tension cable includes at least one variable-radius pulley (2) associated with a support structure (4), such that the at least one variable-radius pulley can rotate about its axis of rotation (3), and a connecting device (5) for connecting to the tension cable (6) is provided at the radially outer portion of the at least one variable-radius pulley. The support structure (4) may be associated with an anchoring element, and a resistance element suitable for elastic deformation is provided between the support structure and the variable-radius pulley (2), which is caused by the rotation of the variable-radius pulley (2) about the support structure in a load rotation direction (8) corresponding to the tension of the tension cable (6), so as to convert the elastic reaction force generated by the deformation of the resistance element into a substantially constant tension applied to the tension cable (6), which is independent of the longitudinal extension length of the tension cable and is within a predetermined length variation range. The unique feature of the invention is that the compensation device includes an emergency brake (9) adapted to prevent the variable radius pulley (2) from suddenly rotating relative to the support structure (4) in a direction opposite to the load rotation direction (8), such sudden rotation being caused, for example, by the breakage of the tension cable (6).

Description

Technical Field

[0001] This invention relates to a compensation device for compensating for the length of tensioned cables. Background Technology

[0002] As is well known, overhead power lines used for energy transmission and distribution or for supplying power to railway locomotives are installed with a well-defined tensile strength that takes into account the tensile breaking strength of the cable, the strength of the supporting structure, and the maximum sag at the center of the curve.

[0003] In order to maintain this pull value while compensating for length changes due to temperature variations in the power line, conventional devices include a compensation device for compensating for changes in the length of the tensioned cable with a substantially constant pull, which is the subject of EP2066523.

[0004] This device includes a resisting element suitable for being positioned between one end of a tensioned cable and an anchoring element, and the resisting element is adapted to generate an elastic reaction force that varies with the length of the cable.

[0005] The device includes a connection means for connecting a resisting element to a cable, and such connection means is adapted to convert the elastic reaction force of the resisting element into a substantially constant tensile force applied to the cable, regardless of the longitudinal length of the cable, and within a predetermined range of length variation.

[0006] The resisting element consists of at least one helical spring, and the connecting device preferably consists of at least one pulley with a variable radius, which is connected to the helical spring and is provided with at least one groove for winding the cable to be tensioned or for connecting a linear element to the cable to be tensioned.

[0007] Therefore, this device can compensate for changes in the length of the tension cable while maintaining a substantially constant tension on the cable.

[0008] This conventional compensation device is not without its drawbacks, including the fact that in the event of an accidental breakage of the tension cable, the return of the helical spring may cause the portion of the cable fixed to the pulley to twist violently, potentially causing it to collide with any object or person near the device, resulting in serious consequences.

[0009] This could undoubtedly cause property damage and could seriously injure any workers who are performing maintenance or other work nearby or at the pole where the device is attached. Summary of the Invention

[0010] The purpose of this invention is to provide a compensation device that overcomes the aforementioned disadvantages while maintaining the advantages of conventional devices.

[0011] Within this objective, the object of the present invention is to provide a compensation device that can ensure the safety of property and personnel by protecting them from potential damage caused by the "whipping" of a tension cable due to its breakage.

[0012] Another object of the present invention is to provide a compensation device that can quickly intervene to ensure the safety of property or personnel.

[0013] Another object of the present invention is to provide a safety device that provides the most comprehensive guarantee of reliability, efficiency, operation and rapid reset services.

[0014] This objective, and these and other objectives, which will become more apparent below, are achieved by a compensation device for compensating for the length of a tension cable. This device includes at least one pulley of variable radius associated with a support structure, such that the pulley is rotatable about its axis of rotation, and a coupling device for connecting to the tension cable is provided at the radially outer portion of the pulley. The support structure is associated with an anchoring element, and a resisting element adapted to undergo elastic deformation is provided between the support structure and the pulley. This elastic deformation is caused by the rotation of the pulley about the support structure in a load rotation direction corresponding to the tension of the tension cable, thereby converting the elastic reaction force generated by the deformation of the resisting element into a tension force applied to the tension cable. The compensation device includes an emergency brake adapted to prevent sudden rotation of the pulley relative to the support structure in a direction opposite to the load rotation direction. Attached Figure Description

[0015] Other features and advantages of the invention will become more apparent from a detailed description of a preferred, but not exclusive, embodiment of a compensation device for compensating for the length of a tension cable, which is illustrated by way of non-limiting example with the aid of the accompanying drawings, in which: Figure 1 This is a perspective view of the compensation device according to the present invention; Figure 2 yes Figure 1 Side view of the compensation device shown; Figure 3 This is a side view of the compensation device shown in the preceding figures, highlighting the emergency brake during normal operation of the compensation device; Figure 4 This is a side view of the compensation device shown in the preceding figures, highlighting the emergency brake during emergency locking of the compensation device. Detailed Implementation

[0016] Referring to the accompanying drawings, the compensation device for compensating for the length of the tension cable (generally indicated by reference numeral 1) includes at least one pulley 2 with a variable radius, which is associated with a support structure 4 such that the at least one pulley with a variable radius can rotate about its axis of rotation 3, and a connecting device 5 for connecting to the tension cable 6 is provided at the radially outer portion of the at least one pulley with a variable radius.

[0017] Advantageously, the support structure 4 can be associated with an anchoring element, and a resisting element, housed in a cover 7 and adapted to undergo elastic deformation, is provided between the support structure and the variable radius pulley 2. This elastic deformation is caused by the rotation of the variable radius pulley 2 about the support structure along a load rotation direction 8 that corresponds to the tension of the tension cable 6, so as to convert the elastic reaction force generated by the deformation of the resisting element into a substantially constant tension applied to the tension cable 6, which is independent of the longitudinal extension length of the tension cable and is within a predetermined length variation range.

[0018] More specifically, the resisting element includes at least one helical spring (in the illustrated embodiment, two helical springs are provided), one end of which is connected to a pulley 2 of variable radius so as to resist rotation of the pulley of variable radius in a direction opposite to the load rotation direction 8, and the other end of which is connected to the support structure 4.

[0019] The phrase "substantially constant" is used to indicate that even if operating conditions change drastically (e.g., temperature changes), the tension maintained on the tension cable 6 is always kept at a constant value, which is suitable for preventing the maximum permissible sag from being exceeded.

[0020] According to the invention, an emergency brake 9 is provided, which is adapted to prevent the variable radius pulley 2 from suddenly rotating relative to the support structure 4 in a direction opposite to the load rotation direction 8, such sudden rotation being caused, for example, by the breakage of the tension cable 6.

[0021] More specifically, in the illustrated embodiment, the emergency brake 9 includes a plurality of pawl-shaped pawls 10 arranged substantially circumferentially relative to each other about a rotation axis 3, for example, four in number, and each of these pawl-shaped pawls is hinged about a first pivot 11 that rotates integrally with a pulley 2 of variable radius.

[0022] like Figure 3 and Figure 4As shown separately, these pawl-shaped pawls 10 can move between a retracted position and a locked position relative to the variable radius pulley 2 in a plane substantially perpendicular to the axis of rotation 3. In the retracted position, the pawls are aligned with each other in the circumferential direction by means of the restoring force of the elastic device 12. In the locked position, since the variable radius pulley 2 generates an angular acceleration opposite to the load rotation direction 8, and this angular acceleration is sufficient to give the pawl-shaped pawls 10 an inertia greater than the elastic restoring force of the elastic device 12, the pawls have an orientation that extends substantially radially relative to the circumferential direction so as to engage with the second pivot 13 that forms an integral part of the support structure 4.

[0023] In the illustrated embodiment, a recess 14 is provided on the radially outer surface of the pawl 10, which is adapted to engage with one of the second pivots 13 in a locked position, and at the same time, the pawl 10 has a shaped and smooth radially outer surface so as to disengage from the second pivot 13 during rotation of the pulley 2 of variable radius in the load rotation direction 8.

[0024] From a mechanical point of view, each pawl-shaped pawl 10 defines a first type of lever, wherein the fulcrum of the first type of lever is defined by its pivotal connection with the corresponding first pivot 11, its resistance is defined by the force of the elastic device 12, and its power is defined by the inertial force caused by the acceleration of the pulley 2 with a variable radius.

[0025] In the illustrated embodiment, the elastic device 12 includes a helical torsion spring for each pawl 10, i.e., a spring whose stress-bearing cross section twists when subjected to compressive stress, which is located between the first portion 16 of the resistance arm defining the first type of lever of the pawl 10 and the support surface located radially inward relative to the first pivot 11 and integrally rotated with the pulley 2 of variable radius.

[0026] Furthermore, also in the illustrated embodiment, the center of gravity of each pawl 10 is defined within its second portion 15, which defines the power arm of the first type of lever.

[0027] Conveniently, the distal portion of each second portion 15 terminates at an adjacent surface 17, which is designed to support and abut against the distal portion of the first portion 16 of the next adjacent pawl 10 in a direction opposite to the load rotation direction 8.

[0028] Advantageously, the profile of the pawl-shaped pawls 10 is designed to prevent them from getting stuck undesirably when engaging and disengaging with the pivots 11, 13.

[0029] From the above description, the operation of the compensation device 1 according to the present invention will become obvious.

[0030] Specifically, during normal operation, the helical spring of the resisting element keeps cable 6 under tension so that it can be adjusted according to changes in cable length.

[0031] Based on the above, any controlled (i.e., slow) rotation of the variable-radius pulley 2 will not trigger the emergency brake 9, such as... Figure 3 As shown.

[0032] In contrast, after, for example, the tension cable 6 breaks, the helical spring returns the variable radius pulley 2 to its original position by applying a sudden acceleration to the pulley 2 in the direction opposite to the load rotation direction 8. This causes the pawl-shaped pawl 10 to open, and its recess 14 engages with the second pivot 13, thereby effectively locking the compensation device 1.

[0033] When the emergency ends, the pawl-shaped pawl 10 separates from the second pivot 13 by rotating the pulley 2 with a variable radius in the load rotation direction 8, and is reset to its retracted position by means of the elastic device 12. This reset movement is further facilitated by the shape and structure of the shaped and smooth radial outer surface of the pawl-shaped pawl 10 sliding on the second pivot 13.

[0034] In fact, it has been found that the compensation device according to the present invention achieves the set goals and objectives.

[0035] The compensation device conceived in this way is easy to modify and vary in many ways, all of which are within the scope of the appended claims.

[0036] Furthermore, all details can be replaced by other technically equivalent components.

[0037] In practice, the materials used (provided they are compatible with the specific application) and, depending on the circumstances, the size and shape can be any material, size, and shape as required and in accordance with existing technology.

[0038] This application claims priority to Italian Patent Application No. 102023000025248, the disclosure of which is incorporated herein by reference.

[0039] Where a technical feature mentioned in any claim is followed by a reference symbol, such reference symbols are included only for the purpose of improving the comprehensibility of the claim, and therefore such reference symbols do not have any limiting effect on the interpretation of each element identified by way of example through these reference symbols.

Claims

1. A compensation device (1) for compensating the length of a tension cable, the compensation device comprising at least one variable-radius pulley (2) associated with a support structure (4) such that the variable-radius pulley is rotatable about a rotation axis (3) of the variable-radius pulley, and a connecting device (5) for connecting to a tension cable (6) is provided at the radially outer portion of at least one of the variable-radius pulleys, the support structure (4) being associated with an anchoring element, and a resistance element suitable for elastic deformation is provided between the support structure (4) and the variable-radius pulley (2), the elastic deformation being caused by the rotation of the variable-radius pulley (2) about the support structure (4) in a load rotation direction (8) corresponding to the tension of the tension cable (6), so as to convert the elastic reaction force generated by the deformation of the resistance element into a tension applied to the tension cable (6); characterized in that, The compensation device includes an emergency brake (9) adapted to prevent the variable radius pulley (2) from rotating suddenly relative to the support structure (4) in a direction opposite to the load rotation direction (8).

2. The compensation device (1) according to claim 1, characterized in that, The emergency brake (9) includes a plurality of pawl-shaped pawls (10) arranged substantially circumferentially relative to each other about the axis of rotation (3), and each of the plurality of pawl-shaped pawls is hinged about a first pivot (11) integrally rotated with the variable radius pulley (2); the pawl-shaped pawls (10) are movable relative to the variable radius pulley (2) in a plane substantially perpendicular to the axis of rotation (3) between a retracted position and a locked position, in which the pawl-shaped pawls (10) are spring-loaded. The resetting force of the elastic device (12) aligns them with each other along the circumferential direction. In the locked position, the variable radius pulley (2) generates an angular acceleration opposite to the rotation direction (8) of the load, and the angular acceleration is sufficient to give the pawl (10) an inertia greater than the elastic resetting force of the elastic device (12). Therefore, the pawl (10) has an orientation that extends substantially radially relative to the circumferential direction so as to engage the second pivot (13) that is integral with the support structure (4).

3. The compensation device (1) according to claim 1 or 2, characterized in that, A recess (14) is provided on the radial outer surface of the pawl-shaped pawl (10), the recess being designed to engage with one of the second pivots (13) in the locked position.

4. The compensation device (1) according to one or more of the preceding claims, characterized in that, The pawl-shaped pawl (10) has a shaped and smooth radial outer surface so as to separate from the second pivot (13) during the rotation of the variable radius pulley (2) along the load rotation direction (8).

5. The compensation device (1) according to one or more of the preceding claims, characterized in that, Each of the pawls (10) defines a first type of lever, wherein the fulcrum of the first type of lever is defined by the pivoting of the pawl to a corresponding first pivot in the first pivot (11), the resistance of the pawl is defined by the force of the elastic device (12), and the power of the pawl is defined by the inertial force caused by the acceleration of the variable radius pulley (2).

6. The compensation device (1) according to one or more of the preceding claims, characterized in that, The elastic device includes a helical torsion spring for each of the pawls (10), the helical torsion spring being located between a first portion (16) of the pawl (9) defining the resistance arm of the first type of lever and a support surface located radially inward relative to the first pivot (11) and integrally rotating with the variable radius pulley (2).

7. The compensation device (1) according to one or more of the preceding claims, characterized in that, The center of gravity of each of the ratchet pawls (10) is defined within a second portion (15) of the ratchet pawl (9), the second portion defining the power arm of the first type of lever.

8. The compensation device (1) according to one or more of the preceding claims, characterized in that, The distal portion of each of the second portions (15) of the pawl (10) terminates at an adjacent surface (17) designed to support the distal portion of the first portion (16) of the next adjacent pawl in the pawl (10) in a direction opposite to the load rotation direction (8).

9. The compensation device (1) according to one or more of the preceding claims, characterized in that, The resisting element includes at least one helical spring, one end of which is connected to the variable radius pulley (2) to resist rotation of the variable radius pulley in a direction opposite to the rotation direction (8) of the load, and the other end of which is connected to the support structure (4).

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