A double-bolt type parallel groove clamp for large cross-section conductor

Abstract

The application discloses a double-bolt type parallel groove clamp for large-section conductor wire, which comprises a bottom plate, a pair of pressing plates arranged above the bottom plate, a self-locking screw sleeve formed by penetrating the pressing plate and the bottom plate through a bolt to extrude and fix the conductor wire, a traction assembly matched with a traction cable to pull the self-locking screw sleeve to keep a fastening state, a contraction neck arranged in the middle of the self-locking screw sleeve, a plurality of fixing rods arranged in the side wall of the contraction neck in a ring shape at equal intervals and used for winding the traction cable, and the traction cable is arranged in a tightening rotation direction along the self-locking screw sleeve, so that a locking direction circumferential pulling force can be continuously applied to the self-locking screw sleeve, reverse rotation loosening problems of the self-locking screw sleeve caused by thermal expansion and cold shrinkage stress of the conductor wire and line wind vibration alternating stress are inhibited, nut loosening and clamping force attenuation problems are reduced, conductor wire slippage caused by clamp loosening is avoided, the long-term outdoor operation demand of large-section high-voltage overhead transmission line is met, and line safety hidden dangers are reduced.

Description

Technical Field

[0001] This invention belongs to the technical field of parallel groove clamps, specifically relating to a double-bolt type parallel groove clamp for large cross-section conductors. Background Technology

[0002] Large cross-section stranded conductors are the main transmission carriers of high-voltage and ultra-high-voltage transmission lines. Parallel groove clamps are the core hardware for connecting and branching conductors in transmission lines. Double-bolt parallel groove clamps are widely used in the construction and maintenance of long-distance overhead transmission lines due to their strong clamping capacity, convenient assembly, and suitability for laying large cross-section conductors.

[0003] Patent application CN112086770B discloses a parallel grooved wire clamp, which includes a wire pressing assembly. The clamp includes a first linkage group connected to one side of the side plate and corresponding to the first base plate, and a second linkage group connected to the other side of the side plate and corresponding to the second base plate. The clamping process of the guide wire and the main wire is realized by rotating the adjusting screw outward, so as to achieve simple and quick connection.

[0004] However, the above-mentioned device only relies on adjusting the screw to squeeze and limit the conductor, which cannot cope with the long-term exposure of overhead transmission lines to the outdoor environment, the large temperature fluctuations between day and night and between seasons, the large thermal expansion and contraction deformation of large cross-section aluminum stranded conductors, and the continuous low-frequency vibration generated by outdoor wind and airflow disturbances, which can easily cause the nut to rotate in the opposite direction and loosen, resulting in the weakening of the clamping force on the conductor and causing the conductor to slip.

[0005] To address this issue, we propose a double-bolt type parallel groove clamp for large cross-section conductors to solve the aforementioned technical problems. Summary of the Invention

[0006] The purpose of this invention is to solve the problem in the prior art where bolts loosen due to thermal expansion and contraction stress and alternating wind vibration stress, resulting in loose wire clamping. This invention provides a double-bolt type parallel groove wire clamp for large cross-section wires.

[0007] The objective of this invention can be achieved through the following technical solutions: A double-bolt type parallel groove wire clamp for large cross-section conductors includes a base plate and a pair of pressure plates disposed above the base plate. The wire is clamped and fixed by bolts passing through the pressure plates and the base plate and engaging with self-locking sleeves. The self-locking sleeves are kept in a tight state by a traction assembly and a traction cable.

[0008] Furthermore, the self-locking sleeve has a contraction neck in the middle, and the side wall of the contraction neck is provided with multiple fixing rods for winding the traction cable at equal intervals.

[0009] Furthermore, the length of the fixing rod shall not exceed the outer diameter of the self-locking sleeve.

[0010] Furthermore, the traction assembly includes a pair of interlocking clamping flaps, which are fixedly mounted on the conductors on both sides of the base plate.

[0011] Furthermore, the upper clamping petal is provided with a connecting rod for fixing the traction cable, and the bottom of the lower clamping petal is provided with an installation plate. A pair of limiting sleeves are provided at one end of the installation plate near the bottom plate, and a sliding rod is inserted into the limiting sleeve.

[0012] Furthermore, a groove corresponding to the position of the slide rod is provided at one end of the base plate near the clamping petal. The slide rod is slidably connected inside the groove. A spring is provided outside the slide rod and inside the groove. A limiting ring corresponding to the position of the spring is provided on the slide rod.

[0013] Furthermore, one end of the traction cable is fitted onto a fixed rod and then wound around the remaining fixed rods in sequence along the tightening direction of the self-locking nut, while the other end is fixedly connected to the connecting rod and the traction cable is tightened.

[0014] Furthermore, a pair of lower mounting grooves are provided on the base plate, and an upper mounting groove corresponding to the position of the lower mounting grooves is provided at the lower end of the pressure plate. A limiting groove is provided on the upper side wall of the lower mounting groove away from the center, and the limiting groove is in the shape of a barb.

[0015] Furthermore, the lower ends of both sides of the pressure plate are provided with expansion springs, and the expansion springs are provided with limit blocks corresponding to the positions of the limit grooves.

[0016] Furthermore, the inner wall of the upper mounting groove is provided with extrusion strips, the ends of which are tapered.

[0017] The beneficial effects of this invention are: This invention uses a traction cable laid along the tightening direction of the self-locking sleeve to continuously apply circumferential tension in the locking direction to the self-locking sleeve. This suppresses the problem of reverse rotation and loosening of the self-locking sleeve caused by the thermal expansion and contraction stress of the conductor and the alternating stress of wind vibration of the line. It reduces the problems of nut loosening and clamping force attenuation, avoids conductor slippage caused by loosening of the clamp, and is suitable for the long-term outdoor operation requirements of large-section high-voltage overhead transmission lines, reducing line safety hazards.

[0018] This invention utilizes an internal sliding rod, a limiting ring, and a return spring in conjunction with a base plate groove to form an elastic adaptive displacement structure. The elastic deformation of the return spring compensates in real time for displacement deviations caused by temperature deformation and wind vibration in large-section conductors, automatically offsetting any slack in the traction cable and maintaining a constant preload. This effectively suppresses the self-locking sleeve from rotating and loosening, thus ensuring the stability of the clamp's hold on the conductor. Furthermore, when the clamping structure formed by the clamping petals loosens due to prolonged operation, the elastic deformation of the return spring, in conjunction with the sliding rod, can still generate a certain traction force, limiting the self-locking sleeve from rotating and loosening, further improving the stability of the clamp's hold on the conductor.

[0019] This invention utilizes extended springs on both sides of the pressure plate, combined with a hook-shaped arc transition limiting groove on the base plate, to form a lateral locking self-locking structure. During the process of the pressure plate pressing down to clamp the wire, the extended springs rebound under pressure, automatically engaging the limiting block with the limiting groove, thus locking the pressure plate and the base plate. Combined with the double-bolt vertical locking structure, this significantly improves the overall structural rigidity and load-bearing capacity of the parallel groove clamp, making it suitable for clamping large-section wires under high tensile force conditions and enhancing the stability of the clamp in holding the wire. Attached Figure Description

[0020] The invention will now be further described with reference to the accompanying drawings.

[0021] Figure 1 This is a schematic diagram of the main body of the invention in its working state; Figure 2 This is an exploded view of the main body of the invention; Figure 3 This is a schematic diagram of the self-locking screw sleeve structure of the present invention; Figure 4 This is a schematic diagram of the structure at the junction of the base plate and the pressure plate of the present invention; Figure 5 This is a schematic diagram of the traction component structure of the present invention; Figure 6 This is a partial cross-sectional structural diagram of the junction of the traction component, the base plate, and the pressure plate of the present invention.

[0022] In the diagram: 1. Base plate; 11. Pressure plate; 111. Upper mounting groove; 112. Extending spring; 113. Extrusion strip; 12. Lower mounting groove; 121. Limiting groove; 13. Sliding groove; 2. Self-locking sleeve; 21. Retracting neck; 22. Fixing rod; 3. Traction cable; 4. Traction assembly; 41. Clamping flap; 42. Connecting rod; 43. Mounting plate; 44. Limiting sleeve; 45. Sliding rod; 451. Limiting ring; 452. Spring. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] Please see Figures 1-2As shown, a double-bolt type parallel groove clamp for large cross-section conductors includes a base plate 1, two sets of pressure plates 11 symmetrically arranged and located above the base plate 1, two sets of bolts, and a self-locking sleeve 2 assembled with matching bolts. The bolts vertically penetrate the pressure plates 11 and the base plate 1 and connect with the self-locking sleeve 2, so as to realize the pressure plates 11 and the base plate 1 to squeeze and clamp the large cross-section conductor. Through the cooperation of the traction cable 3 and the two sets of traction components 4, the self-locking sleeve 2 is pulled to keep it in a locked state. The traction force is used to offset the bolt loosening stress caused by the thermal expansion and contraction of the conductor and the vibration of the line, so that the self-locking sleeve 2 is kept in a locked state for a long time.

[0025] Please see Figure 3 As shown, a ring-shaped contraction neck 21 is coaxially formed in the middle of the self-locking sleeve 2. Multiple cylindrical fixing rods 22 are fixed circumferentially at equal intervals on the outer wall of the contraction neck 21. The fixing rods 22 are integrally cast with the outer wall of the self-locking sleeve 2. The outer end face of the fixing rod 22 is flush with the outer circular surface of the self-locking sleeve 2. The length of the fixing rod 22 is less than the outer diameter of the self-locking sleeve 2 to avoid the fixing rods scraping against the wires and insulation layer during assembly and maintenance. A ring-shaped limiting groove is formed in the middle of each fixing rod 22 to lock and limit the traction cable 3 and prevent the traction cable 3 from slipping off the rod.

[0026] Please see Figure 5 As shown, the traction assembly 4 includes a pair of symmetrically joined clamping petals 41. The inner side of the clamping petals 41 is in contact with the outer contour of the large cross-section conductor. After being joined, they are locked and fixed to the outer wall of the conductor by fastening screws. The clamping petals 41 are made of high elasticity aluminum alloy material, which is suitable for the outer diameter of the large cross-section conductor, and has a high degree of clamping fit without squeezing or damaging the conductor.

[0027] A connecting rod 42 is fixedly connected to the outer wall of the upper clamping petal 41, and an installation plate 43 is provided at the bottom of the lower clamping petal 41. Two sets of cylindrical limiting sleeves 44 are symmetrically fixed on the side of the installation plate 43 facing the bottom plate 1. The limiting sleeves 44 are welded and fixed perpendicularly to the installation plate 43.

[0028] Please see Figures 5-6 As shown, a cylindrical slide rod 45 is coaxially slidably inserted into the limiting sleeve 44. Slide grooves 13 corresponding to the slide rod 45 are opened on both sides of the base plate 1. The end of the slide rod 45 is limited and slidably engaged in the slide groove 13 to prevent the slide rod from disengaging from the slide groove. A return spring 452 is coaxially mounted on the outer wall of the slide rod 45. A limiting ring 451 is provided on the outer wall of the slide rod 45. The limiting ring 451 clamps one end of the spring 452, and the other end of the spring 452 abuts against the inner wall of the slide groove 13. The traction component is adaptively displaced by relying on the spring force to offset the slack problem of the traction cable 3 caused by wind vibration and thermal deformation of the conductor, and maintain constant force traction.

[0029] The traction cable 3 is made of high tensile strength galvanized steel stranded flexible cable, which is resistant to outdoor corrosion and tensile deformation. One end of the traction cable 3 is fixed in the limiting slot of a single fixed rod 22. The traction cable 3 is wound around all the fixed rods 22 in the tightening direction of the self-locking nut 2. After the other end of the traction cable 3 is tensioned, it is locked in the locking hole of the connecting rod 42. The traction cable 3 maintains a constant pre-tight tension and continuously applies circumferential tension in the locking direction of the nut, and in the opposite direction, it inhibits the self-locking nut 2 from rotating and loosening.

[0030] Please see Figure 4 As shown, two sets of lower mounting grooves 12 are symmetrically opened on the upper end of the base plate 1, and upper mounting grooves 111 are correspondingly opened on the lower ends of the two sets of pressure plates 11. The upper and lower mounting grooves together form a circular clamping cavity that is adapted to large cross-section stranded wires. A barbed limiting groove 121 is opened on the upper groove wall of the lower mounting groove 12 on the side away from the center of the wire clamp. The limiting groove 121 has a rounded barbed structure with a smooth transition.

[0031] The lower ends of both sides of the pressure plate 11 are equipped with extension springs 112 by argon arc brazing. The extension springs 112 are made of spring steel and are inclined and outward. A limiting block is set at the lower end of the extension springs 112. The limiting block is engaged with the hook-shaped limiting groove 121. When the pressure plate presses down to clamp the wire, the extension springs 112 are pressed back and the limiting block automatically engages with the limiting groove 121, realizing the self-locking of the pressure plate and the base plate. This effectively prevents the separation between the base plate 1 and the pressure plate 11 and improves the overall structural stability.

[0032] The inner wall of the upper mounting groove 111 is provided with extrusion strips 113. The extrusion strips 113 are arranged at equal intervals along the axial direction of the conductor. The bottom end of the extrusion strips 113 is fixed to the inner wall of the pressure plate, and the end is a smooth conical structure, which greatly improves the clamping friction between the wire clamp and the conductor, prevents the slippage of large cross-section conductors, and avoids sharp edges from cutting the anti-corrosion coating of the conductor.

[0033] Working principle: During the assembly of the parallel groove clamp, the large-section wire is first placed inside the lower mounting groove 12 of the base plate 1, and the two sets of pressure plates 11 are fastened together so that the upper mounting groove 111 and the lower mounting groove 12 surround and clamp the wire. The bolt is vertically inserted and the self-locking sleeving 2 is tightened to complete the initial locking. During the pressing of the pressure plate 11, the spring steel expansion pieces 112 on both sides are compressed and then spring back, and the lower limit block automatically engages with the hook-type limit groove 121 of the base plate 1 to achieve mechanical self-locking between the pressure plate 11 and the base plate 1. Then the two sets of traction components 4 are installed. The clamping petal 41 is locked and fixed to the outer wall of the conductor. The slide rod 45 is inserted into the limiting sleeve 44 of the mounting plate 43. One end of the traction cable 3 is inserted into the slot of the fixing rod 22 of the self-locking screw sleeve 2. After being wound along the tightening direction of the screw sleeve, the other end is tensioned and fixed to the connecting rod 42. During the operation of the line, the traction cable 3 continuously applies circumferential locking traction force to counteract the loosening stress caused by the thermal expansion and contraction of the conductor and the wind vibration of the line, prevent the self-locking screw sleeve 2 from rotating and loosening, prevent the conductor from slipping, and effectively ensure the clamping stability and locking reliability of the clamp.

[0034] It should be noted that, in this document, terms such as “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0035] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.

Claims

1. A double-bolt type parallel groove clamp for large cross-section conductors, comprising a base plate (1), characterized in that: A pair of pressure plates (11) set above the base plate (1) are connected by bolts through the pressure plates (11) and the base plate (1) to form a self-locking sleeve (2) to compress and fix the wire. The self-locking sleeve (2) is pulled by the traction assembly (4) and the traction cable (3) to keep it in a tight state.

2. The double-bolt type parallel groove clamp for large cross-section conductors according to claim 1, characterized in that: The self-locking nut (2) has a contraction neck (21) in the middle, and the side wall of the contraction neck (21) is provided with a plurality of fixing rods (22) for winding the traction cable (3) at equal intervals.

3. A double-bolt type parallel groove clamp for large cross-section conductors according to claim 2, characterized in that: The length of the fixing rod (22) does not exceed the outer diameter of the self-locking sleeve (2).

4. A double-bolt type parallel groove clamp for large cross-section conductors according to claim 1, characterized in that: The traction assembly (4) includes a pair of clamping petals (41) that fit together, and the clamping petals (41) are fixedly installed on the conductors on both sides of the base plate (1).

5. A double-bolt type parallel groove clamp for large cross-section conductors according to claim 4, characterized in that: The upper clamping petal (41) is provided with a connecting rod (42) for fixing the traction cable (3), and the bottom of the lower clamping petal (41) is provided with an mounting plate (43). The mounting plate (43) is provided with a pair of limiting sleeves (44) at one end near the bottom plate (1), and a sliding rod (45) is inserted inside the limiting sleeve (44).

6. A double-bolt type parallel groove clamp for large cross-section conductors according to claim 5, characterized in that: The base plate (1) has a groove (13) at one end near the clamping petal (41) that corresponds to the position of the slide rod (45). The slide rod (45) is slidably connected inside the groove (13). A spring (452) is provided outside the slide rod (45) and inside the groove (13). A limiting ring (451) corresponding to the position of the spring (452) is provided on the slide rod (45).

7. A double-bolt type parallel groove clamp for large cross-section conductors according to claim 5, characterized in that: One end of the traction cable (3) is sleeved on a fixed rod (22) and is wound around the other fixed rods (22) in sequence along the tightening direction of the self-locking nut (2). The other end is fixedly connected to the connecting rod (42) and the traction cable (3) is tightened.

8. A double-bolt type parallel groove clamp for large cross-section conductors according to claim 1, characterized in that: The base plate (1) has a pair of lower mounting grooves (12), and the pressure plate (11) has an upper mounting groove (111) at the lower end corresponding to the position of the lower mounting grooves (12). The upper side wall of the lower mounting groove (12) away from the center has a limiting groove (121), and the limiting groove (121) is in the shape of a barb.

9. A double-bolt type parallel groove clamp for large cross-section conductors according to claim 8, characterized in that: The lower ends of the two side walls of the pressure plate (11) are provided with expansion springs (112), and the expansion springs (112) are provided with limiting blocks corresponding to the positions of the limiting grooves (121).

10. A double-bolt type parallel groove clamp for large cross-section conductors according to claim 8, characterized in that: The inner wall of the upper mounting groove (111) is provided with an extrusion strip (113), and the end of the extrusion strip (113) is tapered.

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