Suspension string safety backup wire clamp structure of overhead line and implementation method

Abstract

The invention discloses a suspension string safety backup wire clamp structure of an overhead line and an implementation method, and relates to the technical field of safety protection of high-voltage transmission lines. A suspension string safety backup wire clamp structure of an overhead line comprises a wire clamp assembly and a connecting assembly, the wire clamp assembly is connected with a yoke plate through the connecting assembly, and the connecting assembly is further provided with at least one hinge connecting rod; the connecting assembly comprises a long screw rod, a bolt rod, a U-shaped frame and a breakable connecting mechanism. According to the suspension string safety backup wire clamp structure of the overhead line and the implementation method, through the double-path design of the breakable cushion block and the loose hinge connecting rod, when a system normally operates, the load is completely borne by the main suspension wire clamp, and the backup wire clamp keeps the posture through rigid supporting of the breakable cushion block; and a hinge connecting rod serving as a final bearing unit is in an unstressed loose state, so that thorough mechanical decoupling is realized, and self fatigue accumulation of the backup system is avoided.

Description

Technical Field

[0001] This invention relates to the field of safety protection technology for high-voltage transmission lines, and in particular to a suspension string safety backup clamp structure and implementation method for overhead lines. Background Technology

[0002] In high-voltage and ultra-high-voltage overhead transmission lines, conductors are connected to insulator strings and suspended from towers via suspension clamps. These suspension clamps bear the long-term weight of the conductors, wind loads, icing loads, and alternating stresses caused by wind-induced vibration and galloping. This makes them prone to metal fatigue at stress concentration points such as the clamp hull and U-shaped hanging rings, potentially leading to fracture failure. Furthermore, lightning strikes, material defects, and improper installation can also cause sudden damage to the suspension clamps.

[0003] Therefore, there is an urgent need to develop a new type of suspension string safety backup clamp structure that can achieve complete mechanical decoupling from the main system during normal operation, and can instantly and reliably take over the load when the main suspension clamp fails. It also has the advantages of visible status, convenient installation, and adaptability to the dynamic movement of conductors. Summary of the Invention

[0004] The purpose of this invention is to provide a safety backup clamp structure and implementation method for overhead lines. Through the dual-path design of the breakable pad and the relaxed hinge link, the load is completely borne by the main suspension clamp during normal operation. The backup clamp maintains its posture through the rigid support of the breakable pad, while the hinge link, as the final load-bearing unit, is in a relaxed state without force. This achieves complete mechanical decoupling and solves the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a suspension string safety backup clamp structure for overhead lines, comprising a clamp assembly and a connecting assembly, wherein the clamp assembly is connected to a connecting plate via the connecting assembly, and the connecting assembly is further provided with at least one hinge link; the connecting assembly comprises a long screw, a bolt rod, a U-shaped frame, and a breakable connection mechanism, wherein the breakable connection mechanism is disposed on the main force transmission path between the long screw and the connecting plate, for providing a rigid connection under normal conditions, and breaking to release the rigid connection when subjected to a load exceeding a preset threshold;

[0006] Preferably, the breakable connection mechanism includes a breakable pad, and the breakable pad has at least one annular pre-set weak groove.

[0007] Preferably, the lower end of the U-shaped frame is hinged to the wire clamp assembly, and the upper end is connected to the connecting plate through a bolt rod with a breakable pad, wherein the breakable pad is clamped between the U-shaped frame and the connecting plate.

[0008] Preferably, a support spring is fitted onto the section of the long screw located between the ear plate and the U-shaped frame.

[0009] Preferably, the wire clamp assembly includes a wire clamp body, an inner liner, and a U-bolt. The inner liner includes an upper liner layer and a lower substrate that contact the cable. The lower surface of the lower substrate is provided with an arc-shaped groove for increasing the friction with the inner wall of the wire clamp body. A pressure plate is provided above the upper liner layer.

[0010] Preferably, a spring washer is fitted onto the U-shaped bolt above the movable hole.

[0011] Preferably, the pressure plate has a movable hole for the U-bolt to pass through.

[0012] Preferably, the hinge link includes a lower connecting rod and an upper connecting rod connected by a threaded sleeve, and the total length of the hinge link can be adjusted by rotating the threaded sleeve.

[0013] Another technical problem to be solved by the present invention is to provide a method for implementing a suspension string safety backup clamp structure for overhead lines, comprising the following steps:

[0014] S1: Secure the wire clamp assembly to the conductor;

[0015] S2: Assemble the connecting assembly and hinge it to the wire clamp assembly, wherein the breakable connecting mechanism is installed and pre-tightened to form a rigid connection with the connecting plate;

[0016] S3: Hinge the two ends of the hinge link to the wire clamp assembly and the connecting plate respectively;

[0017] S4: Adjust the length of the hinge link so that it is in a relaxed state when the breakable connection mechanism is working normally, and form the preset gap;

[0018] S5: Verify that under normal conditions, the hinge link can swing freely without being subjected to force, while the connection at the breakable connection mechanism is rigid and not loose.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] 1. This invention, through a dual-path design of a breakable pad and a relaxed hinge link, ensures that during normal operation, the load is entirely borne by the main suspension clamp, while the backup clamp maintains its posture through the rigid support of the breakable pad. The hinge link, as the final load-bearing unit, is in a relaxed state without stress, achieving complete mechanical decoupling and avoiding fatigue accumulation in the backup system itself. When the main suspension clamp fails, the breakable pad shears and breaks at a precisely designed threshold, releasing the rigid constraint. The falling conductor instantly tightens the hinge link with a preset gap, completing a millisecond-level, seamless load path switching with extremely high safety and reliability.

[0021] 2. In this invention, the inner liner adopts a design with an arc-shaped groove and a long waist-shaped pressure plate. While providing strong grip, it allows the wire to rotate and swing slightly within the limit range, avoiding the stress concentration and fretting wear of the wire caused by traditional rigid clamping. The support spring in the connecting assembly can effectively eliminate the assembly gap between the ear plate and the U-shaped frame, absorb high-frequency vibration during operation, prevent impact and noise, and at the same time retain the necessary flexibility for the system to follow the swing of the wire. Attached Figure Description

[0022] Figure 1 This is an overall structural diagram of the overhead line suspension string safety backup clamp structure of the present invention.

[0023] Figure 2 This is a test diagram of the suspension string safety backup clamp structure for overhead lines according to the present invention.

[0024] Figure 3 This is a cross-sectional view of the suspension string safety backup clamp structure for overhead lines according to the present invention.

[0025] Figure 4 This is a diagram showing the working state of the liner of the present invention;

[0026] Figure 5 An exploded view of the overhead line suspension string safety backup clamp of the present invention.

[0027] Figure 6 This is a structural diagram of the connection between the U-shaped frame and the breakable pad of the present invention;

[0028] Figure 7 This is a schematic diagram of the hinge link connection structure of the present invention.

[0029] In the diagram: 1. Wire clamp assembly; 11. Wire clamp body; 111. Ear plate; 112. Through hole; 12. Inner liner; 121. Lower substrate; 1211. Arc groove; 122. Upper liner; 1221. Pressure plate; 12211. Movable hole; 13. U-bolt; 131. First nut; 132. Spring washer; 2. Connecting assembly; 21. Long screw; 211. Support spring; 212. Second nut; 213. Third nut; 214. Cotter pin; 22. Bolt rod; 221. Breakable pad; 2211. First groove; 2212. Second groove; 2213. Third groove; 222. Fourth nut; 23. U-shaped frame; 3. Connecting plate; 4. Hinge link; 41. Lower connecting rod; 42. Upper connecting rod; 421. Fork; 43. Threaded sleeve. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Please see Figures 1-7 A suspension string safety backup clamp structure for an overhead line includes a clamp assembly 1 and a connecting assembly 2. The clamp assembly 1 is connected to a connecting plate 3 through the connecting assembly 2, and a hinge link 4 is also provided on the connecting assembly 2.

[0032] Specifically, the wire clamp assembly 1 includes a wire clamp body 11, an inner liner 12, and a U-bolt 13. The upper end of the wire clamp body 11 is provided with an ear plate 111, and the inner liner 12 is provided inside the wire clamp body 11. The inner liner 12 clamps the cable to prevent the cable from loosening. The wire clamp body 11 is provided with a through hole 112 that matches the U-bolt 13. The two ends of the U-bolt 13 are respectively inserted into the lower end of the through hole 112, and the upper end of the U-bolt 13 is locked by a first nut 131.

[0033] The inner liner 12 includes a lower substrate 121 and an upper liner 122. Both the lower substrate 121 and the upper liner 122 are arc-shaped structures that match the shape of the cable and cover and support the cable. Arc-shaped grooves 1211 are evenly spaced on the lower surface of the lower substrate 121. The lower surface of the lower substrate 121 contacts the inner wall of the clamp body 11. When the lower substrate 121 is squeezed, the arc-shaped grooves 1211 deform, making the lower substrate 121 in close contact with the clamp body 11, increasing friction and preventing the cable from sliding horizontally. A pressure plate 1221 is provided on the upper surface of the upper liner 122. The pressure plate 1221 has symmetrical movable holes 12211 on both sides. The movable holes 12211 are sleeved with U-bolts 13. A spring washer 132 is sleeved on the U-bolt 13 above the movable holes 12211. A washer is provided between the spring washer 132 and the first nut 131. By tightening the first nut 131 on the U-bolt 13, pressure can be applied to the spring washer 132 by squeezing the washer, thereby applying pressure to the upper liner 122 through the pressure plate 1221. In addition, by cooperating with the lower substrate 121, the cable is clamped. In addition, the movable hole 12211 is an elongated hole. When the cable shakes, swings and rotates, the lower substrate 121 and the upper liner 122 can cover the cable and rotate synchronously. The movable hole 12211 provides a gap space for the cable to rotate.

[0034] Furthermore, the connecting assembly 2 includes a long screw 21, a bolt rod 22, and a U-shaped frame 23. The long screw 21 passes through the ear plate 111 and the U-shaped frame 23. The U-shaped frame 23 is disposed between the ear plates 111 and is connected to the connecting plate 3 through the bolt rod 22 passing through its upper end.

[0035] Specifically, a support spring 211 and a washer are provided on the long screw 21 between the ear plate 111 and the U-shaped frame 23. One end of the support spring 211 abuts against the ear plate 111, and the other end abuts against the washer. Under the action of the support spring 211, the washer abuts against the U-shaped frame 23. The support spring 211 fills the gap between the ear plate 111 and the U-shaped frame 23, preventing the U-shaped frame 23 from loosening, and also meeting the needs of cable swing. The long screw on the outside of the ear plate 111... A second nut 212 is provided on the rod 21. The second nut 212 meshes with the long screw 21 and is used to adjust the tightness of the support spring 211. A third nut 213 is also meshed at the end of the long screw 21. A hinge link 4 is provided between the third nut 213 and the second nut 212. The third nut 213 is used to fix the position of the hinge link 4. Both ends of the long screw 21 are provided with cotter pins 214 to prevent the third nut 213 and the second nut 212 from loosening.

[0036] More specifically, the bolt rod 22 passes through the U-shaped frame 23, and the bolt rod 22 between the U-shaped frames 23 passes through the connecting plate 4 and is locked by the fourth nut 222. A cotter pin 214 is also provided on the bolt rod 22. A breakable pad 221 is provided at the position where the bolt rod 22 is placed inside the U-shaped frame 23. The breakable pad 221 is a high-precision nylon shear sleeve with a through hole in the center, which is fitted onto the bolt rod 22. A pre-set annular first groove 2211 is machined in the middle of the outer cylindrical surface of the breakable pad 221. A second groove 2212 is provided on the inner wall of the breakable pad 221 near the first groove 2211. A third groove 2213 also opens and closes inside the breakable pad 221. The bolt rod 221 passes through the first groove 2212... 211. The second groove 2212 and the third groove 2213 make the breakable pad 221 have weak points. The multiple grooves are for precise control of the fracture position and force value to ensure the consistency of the action. Under normal circumstances, the breakable pad 221 abuts against the U-shaped frame 23 and the connecting plate 3. The U-shaped frame 23 is clamped outside the breakable pad 221. After the main suspension clamp breaks, the downward force of the conductor load is completely converted into a downward pulling force on the shear pin assembly through the clamp assembly 1, which drives the U-shaped frame 23 to move closer together. When this force exceeds the design shear threshold at the groove of the breakable pad 221, the breakable pad 221 is neatly sheared at the groove. The U-shaped frame 23 is tightened with the bolt rod 22, and the clamp assembly 1 falls under the action of gravity.

[0037] It is important to understand that the hinge link 4 includes a lower connecting rod 41, an upper connecting rod 42, and a threaded sleeve 43. The upper end of the lower connecting rod 41 and the lower end of the upper connecting rod 42 are engaged by the threaded sleeve 43. By tightening the threaded sleeve 43, the lengths of the lower connecting rod 41 and the upper connecting rod 42 can be adjusted. The lower end of the lower connecting rod 41 is sleeved with the long screw 21. The upper end of the upper connecting rod 42 is provided with a fork 421, which is hinged to the connecting plate 3 (not shown in the figure). At the moment the main suspension clamp breaks, the clamp assembly 1 and the connecting plate 3 are straightened and tightened through another set of hinge links. Under normal conditions, the hinge link 4 is in a relaxed state, that is, the length of the hinge link is slightly greater than its theoretical length in the fully tightened state, thus forming a controllable gap, such as 5-30mm. This gap is visible to the naked eye and is also the basis for inspection. The hinge link 4 has extremely high strength and immediately bears the mechanical load of the conductor, completing a millisecond-level safe switching.

[0038] The present invention discloses a method for implementing a suspension string safety backup clamp structure for an overhead line, comprising the following steps:

[0039] Step 1: Component pre-assembly and cable clamping installation

[0040] S1.1: Place the lower substrate 121 of the inner liner 12 into the inner cavity of the wire clamp body 11, so that the arc groove 1211 on its lower surface contacts the wire clamp body 11, and place the wire in the arc concave surface of the lower substrate 121.

[0041] S1.2: Cover the upper liner 122 and the pressure plate 1221 connected thereto, so that the elongated slotted movable holes 12211 on both sides of the pressure plate 1221 are aligned with the through holes 112 on the clamp body 11.

[0042] S1.3: Pass the U-bolt 13 through the through hole 112 and the movable hole 12211 from below, and put the spring washer 132 and the washer on the threaded end of the U-bolt 13 in sequence, and then screw in the first nut 131;

[0043] S1.4: Using a torque wrench, tighten the two first nuts 131 step by step according to the designed torque. During the tightening process, the pressure is evenly transmitted to the upper liner 122 and the lower substrate 121 through the pressure plate 1221. The arc groove 1211 of the lower substrate 121 undergoes elastic deformation, making it fit tightly against the inner wall of the wire clamp body 11, generating huge static friction force, thereby firmly holding the wire, while allowing the wire to rotate slightly within the limit range.

[0044] Step 2: Installation of connecting components and triggering mechanism, and setting of preload.

[0045] S2.1: Place the U-shaped frame 23 between the ear plates 111 of the wire clamp body 11, and pass the long screw 21 through one ear plate 111, the U-shaped frame 23 and the other ear plate 111 in sequence. In the section of the long screw 21 between the ear plate 111 and the U-shaped frame 23, install the support spring 211 and the washer respectively. One end of the support spring 211 presses against the ear plate 111, and the other end presses against the side of the U-shaped frame 23 through the washer.

[0046] S2.2: Screw the second nuts 212 into both ends of the long screw 21 and tighten them symmetrically to compress the support spring 211 to the designed preload state. This preload is intended to eliminate the gap between the ear plate 111 and the U-shaped frame 23 to prevent impact noise during operation, while retaining sufficient flexibility to accommodate swing.

[0047] S2.3: Place the lower end of the lower connecting rod 41 of the hinge link 4 onto the long screw 21, located outside the second nut 212. Then screw in the third nut 213 until it just contacts the end of the lower connecting rod 41, without fully locking it. Finally, install cotter pins 214 at both ends of the long screw 21 to lock all nuts.

[0048] Step 3: Integration and installation of the triggering mechanism

[0049] S3.1: Insert the breakable pad 221 into the designated position of the bolt rod 22, which should be aligned with the mounting hole at the upper end of the U-shaped bracket 23;

[0050] S3.2: Pass the bolt rod 22 through one side of the U-shaped frame 23, the breakable pad 221, and the connecting plate 3 in sequence. Screw the fourth nut 222 into the upper end of the bolt rod 22 and tighten it with a torque wrench according to the precise calculated torque value. This torque value should ensure that the breakable pad 221 is subjected to sufficient axial compression preload so that its outer wall forms a stable rigid connection with the inner wall of the U-shaped frame 23 and its end face forms a connection with the connecting plate 3. At the same time, ensure that its weak links, such as the first groove 2211, are in a preset stress state. After tightening, install the cotter pin 214 to lock the fourth nut 222.

[0051] Step 4: Adjustment of redundant load-bearing paths and setting of preset gaps

[0052] S4.1: Connect the fork 421 of the connecting rod 42 on the hinge link 4 to the reserved independent hinge point on the connecting plate 3 through a pin.

[0053] S4.2: Rotate the threaded sleeve 43 to extend the total length of the hinge link 4 until it is obviously in a relaxed state. Under normal working conditions, even if the conductor swings at the maximum amplitude, the hinge link 4 will never be under force, and the load will be borne entirely by the path where the breakable pad 221 is located.

[0054] S4.3: After adjustment, use a lock nut or apply thread-locking agent to prevent the threaded sleeve 43 from rotating and changing its length during vibration.

[0055] Step 5: Overall Functionality Verification and Status Confirmation

[0056] Check that all cotter pins 214 are installed in place and properly opened. Manually check that each hinge point rotates flexibly without jamming. Slightly shake the clamp assembly 1. You should feel the cushioning of the support spring 211 and observe that the hinge link 4 swings freely without straightening. At the same time, the U-shaped frame 23 and the connecting plate 3 are rigidly connected by the breakable pad 221 without loosening.

[0057] After installation and debugging using the above methods, the backup clamp structure achieves the following working cycle:

[0058] During normal operation: the conductor load is borne by the main suspension clamp, and the backup clamp maintains the structural position through the pre-tightened breakable pad 221. The hinge link 4 is in a relaxed and idle state, achieving complete mechanical decoupling. When the main suspension clamp fails: the huge tensile force of the falling conductor is converted into a shear force on the breakable pad 221 through the U-shaped frame 23. When the force exceeds its design threshold, the pad breaks precisely at the first groove 2211, the original rigid connection is released, and when the clamp assembly 1 falls to the preset gap, the relaxed hinge link 4 is instantly straightened and tightened, becoming the only load path to bear the conductor load. Since the two ends of the hinge link 4 are hinged, the conductor can still swing safely.

[0059] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A suspension string safety backup clamp structure for an overhead line, comprising a clamp assembly (1) and a connecting assembly (2), characterized in that, The clamp assembly (1) is connected to the connecting plate (3) via the connecting assembly (2). The connecting assembly (2) is also provided with at least one hinge link (4). The connecting assembly (2) includes a long screw (21), a bolt rod (22), a U-shaped frame (23), and a breakable connection mechanism. The breakable connection mechanism is located on the main force transmission path between the long screw (21) and the connecting plate (3) and is used to provide a rigid connection under normal conditions and break to release the rigid connection when subjected to a load exceeding a preset threshold.

2. The suspension string safety backup clamp structure for an overhead line according to claim 1, characterized in that, The breakable connection mechanism includes a breakable pad (221), on which at least one annular pre-set weak groove is provided.

3. The suspension string safety backup clamp structure for an overhead line according to claim 2, characterized in that, The lower end of the U-shaped frame (23) is hinged to the wire clamp assembly (1), and the upper end is connected to the connecting plate (3) through a bolt rod (22) with a breakable pad (221). The breakable pad (221) is clamped between the U-shaped frame (23) and the connecting plate (3).

4. The suspension string safety backup clamp structure for an overhead line according to claim 3, characterized in that, The long screw (21) is fitted with a support spring (211) on the section between the ear plate (111) and the U-shaped frame (23).

5. The suspension string safety backup clamp structure for an overhead line according to claim 4, characterized in that, The wire clamp assembly (1) includes a wire clamp body (11), an inner liner (12) and a U-bolt (13). The inner liner (12) includes an upper liner (122) and a lower substrate (121) that are in contact with the cable. The lower surface of the lower substrate (121) is provided with an arc groove (1211) for increasing the friction with the inner wall of the wire clamp body (11). A pressure plate (1221) is provided above the upper liner (122).

6. The suspension string safety backup clamp structure for an overhead line according to claim 5, characterized in that, A spring washer (132) is fitted onto the U-bolt (13) above the movable hole (12211).

7. The suspension string safety backup clamp structure for an overhead line according to claim 6, characterized in that, The pressure plate (1221) has a movable hole (12211) for the U-bolt (13) to pass through.

8. The suspension string safety backup clamp structure for an overhead line according to claim 7, characterized in that, The hinge link (4) includes a lower connecting rod (41) and an upper connecting rod (42) connected by a threaded sleeve (43). The total length of the hinge link (4) can be adjusted by rotating the threaded sleeve (43).

9. A method for implementing the suspension string safety backup clamp structure for an overhead line as described in claim 8, characterized in that, Includes the following steps: S1: Install and secure the wire clamp assembly (1) onto the wire; S2: Assemble the connecting assembly (2) and hinge it to the wire clamp assembly (1), wherein the breakable connecting mechanism is installed and pre-tightened to form a rigid connection with the connecting plate (3); S3: Hinge the two ends of the hinge link (4) to the wire clamp assembly (1) and the connecting plate (3) respectively; S4: Adjust the length of the hinge link (4) so ​​that it is in a relaxed state when the breakable connection mechanism is working normally, and form the preset gap; S5: Verify that under normal conditions, the hinge link (4) can swing freely without being subjected to force, while the connection at the breakable connection mechanism is rigid and not loose.

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