A cable grounding device

Abstract

The utility model discloses a cable grounding device, apply to wiring device technical field, including the shielding ring of inside having inner annular groove, the contact finger spring of being sleeved in the inner annular groove, after the shielding layer of cable is turned over and enters the shielding ring, the inside of contact finger spring is contacted with the shielding layer and the shielding layer partial shielding silk is embedded in the contact finger spring, the outside of contact finger spring is extruded contact with the inner annular groove, still include the metal shell of with shielding ring outer wall passes through O type ring connection, the sealing ring, the clamping claw and the galling nut of being connected in proper order in the front end of metal shell, and with the connecting nut assembly of metal shell rear end connection. This cable grounding device can fix the shielding layer of cable, and the production assembly is convenient, and shielding connection is stable and reliable.

Description

Technical Field

[0001] This utility model relates to the field of wiring device technology, and in particular to a cable grounding device. Background Technology

[0002] In existing technology, cable grounding involves the following steps: First, the cable shielding layer is folded outwards and fitted onto a shielding ring, then the shielding ring is installed into a metal casing. The shielding ring is initially positioned against the metal casing by the radial pressure of the O-ring. Subsequently, a sealing ring, clamping claws, and a tightening nut are installed in sequence. When the tightening nut is tightened, its threads compress the sealing ring, ultimately securing the cable. Through this structure, the shielding ring presses the cable shielding layer against the metal casing, completing the shielding grounding.

[0003] However, this solution has the following drawbacks: During the tightening of the nut, the sealing ring is deformed under pressure and causes the cable to rotate. The shielding layer rotates synchronously with the cable, while the shielding ring remains stationary with the metal shell. This makes the shielding layer extremely easy to tear, resulting in grounding failure. The shielding ring is a rigid component, and the cable shielding layer is only rigidly pressed together. It cannot be pre-fixed during assembly and requires repeated manual adjustments, which is time-consuming, labor-intensive, and prone to poor contact.

[0004] In summary, how to effectively solve the problems of easy breakage and difficult assembly during cable grounding connections is an urgent issue that needs to be addressed by those skilled in the art. Utility Model Content

[0005] The purpose of this invention is to provide a cable grounding device that can fix the cable shielding layer, facilitate production and assembly, and ensure stable and reliable shielding connection.

[0006] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0007] A cable grounding device includes a shielding ring with an inner annular groove on its inner side, and a contact spring fitted inside the inner annular groove. After the cable's shielding layer is turned outward and inserted into the shielding ring, the inner side of the contact spring contacts the shielding layer, and part of the shielding wire of the shielding layer is embedded in the contact spring. The outer side of the contact spring is in compressive contact with the inner annular groove. The device also includes a metal shell connected to the outer wall of the shielding ring via an O-ring, a sealing ring, a clamping claw, and a tightening nut sequentially connected to the front end of the metal shell, and a connecting nut assembly connected to the rear end of the metal shell.

[0008] Optionally, the inner annular groove is a stepped groove, which allows for the installation of bushings of different diameters to match various specifications of the finger springs.

[0009] Optionally, it also includes a metal adjusting ring connected within the inner annular groove. The outer side of the metal adjusting ring contacts the inner annular groove, and the inner side of the metal adjusting ring is in compression contact with the outer side of the touch finger spring. The inner diameter of the metal adjusting ring can be radially adjusted to match various sizes of the touch finger spring.

[0010] Optionally, the metal adjusting ring includes an inner ring, an outer ring, and an elastic element connecting the inner ring and the outer ring. The elastic element is evenly distributed in the circumferential direction of the inner ring. The elastic element contracts radially along the inner annular groove. The inner ring can contract circumferentially. The inner side of the inner ring is in compression contact with the outer side of the finger spring, and the outer side of the outer ring is in contact with the inner annular groove.

[0011] Optionally, the inner ring includes at least two arc-shaped segments that are inserted at the ends, so as to adjust the diameter of the inner ring to achieve compression contact between the inner side of the inner ring and the outer side of the finger spring.

[0012] Optionally, the arc-shaped segment is a flexible metal sheet used to adapt to the outer contour of the finger spring.

[0013] Optionally, the cross-sectional profile of the inner ring matches the outer profile of the finger spring, and the cross-sectional profile of the outer ring matches the cross-sectional profile of the inner annular groove.

[0014] Optionally, the metal adjusting ring is a circular leaf spring, the inner side of the leaf spring is in compression contact with the outer side of the finger spring, the outer side is in contact with the inner annular groove, and the leaf spring contracts radially along the inner annular groove.

[0015] Optionally, the inner wall of the finger spring is provided with serrations, and the serrations are in contact with the shielding layer.

[0016] Optionally, the shielding ring is provided with a plurality of parallel inner annular grooves along the axial direction, and the cable and the shielding ring are connected by a plurality of the contact finger springs.

[0017] The beneficial effect of this utility model is that the cable grounding device provided by this utility model has an inner annular groove in the inner hole of the shielding ring. The width of the inner annular groove is slightly larger than the wire diameter of the contact finger spring. The contact finger spring is pressed into the bottom of the groove with a set interference to form a constant radial elastic force.

[0018] The contact spring can be a slanted coil spring, with a free inner diameter smaller than the cable's outer diameter. Each coil deforms independently to form parallel contact points. The inner side forms an embedded engagement with the cable's outward-facing shielding layer. As the shielding wire is inserted, it is micro-cut by the edge of the contact spring and embedded in the gap, preventing axial slippage and ensuring 360° electrical continuity. The outer side has an interference fit with the shielding ring, forming a low-resistance grounding path. This allows the cable to rotate slightly relative to the shielding ring without stretching the shielding layer.

[0019] The front external thread of the metal casing engages with the tightening nut, and the rear external thread mates with the connecting nut assembly. A stepped hole at the front section accommodates a shielding ring, with an O-ring embedded in the outer annular groove of the shielding ring's outer circumference, forming a seal with the inner hole of the metal casing and providing initial positioning. A sealing ring and clamping claws are sequentially installed at the front of the metal casing, and the tightening nut connects to the external thread at the front of the metal casing. The tightening nut, due to thread compression, ultimately secures the product. After passing through the shielding ring and the metal casing, the cable is terminated by the connecting nut assembly.

[0020] The cable grounding device provided by this utility model features a contact spring installed in the inner annular groove of a shielding ring. The cable's shielding layer is folded outwards and inserted into the shielding ring, allowing the contact spring to make direct contact with the shielding layer. Due to the radial elastic force of the spring, part of the shielding wire is embedded in the spring ring gap, achieving stable engagement and ensuring stable contact. The contact spring and the inner annular groove are interference-fitted, while retaining rotational freedom. When the cable rotates, the contact spring moves synchronously, preventing the shielding wire from being pulled and broken. During assembly, the continuous elastic force of the contact spring self-locks the shielding ring onto the cable, preventing accidental detachment. Simultaneously, the contact spring maintains elastic compression with the metal shell, resulting in low grounding impedance and vibration resistance. No secondary tightening or adjustment is required, ensuring shielding conductivity in one step and reliable grounding. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A schematic diagram of the cable grounding device provided in a specific embodiment of this utility model;

[0023] Figure 2 This is a schematic diagram of the shielding ring structure;

[0024] Figure 3 This is a schematic diagram showing the connection between the shielding ring and the contact finger spring;

[0025] Figure 4 A schematic diagram of inserting a cable into a contact spring;

[0026] Figure 5 Isometric view of the cable insertion spring;

[0027] Figure 6 This is a schematic diagram showing the connection between the metal casing and the shielding ring;

[0028] Figure 7 This is a schematic diagram showing the connection between the metal casing and the tightening nut.

[0029] Figure 8 This is a schematic diagram showing the connection between the metal casing and the connecting nut assembly.

[0030] Figure label:

[0031] 1-Connecting nut assembly; 2-Metal housing; 3-Contact finger spring; 4-Shielding ring; 41-Inner annular groove; 42-Outer annular groove; 5-O-ring; 6-Sealing ring; 7-Clamping claw; 8-Tightening nut; 9-Cable; 91-Shielding layer. Detailed Implementation

[0032] The core of this utility model is to provide a cable grounding device, which can fix the cable shielding layer, facilitate production and assembly, and ensure stable and reliable shielding connection.

[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0034] Please refer to Figures 1 to 8 This is a schematic diagram of a cable grounding device provided in a specific embodiment of this utility model.

[0035] In one specific embodiment, the cable grounding device provided by this utility model includes a shielding ring 4 with an inner annular groove 41 on its inner side, and a finger spring 3 fitted inside the inner annular groove 41. After the shielding layer 91 of the cable 9 is turned outward and inserted into the shielding ring 4, the inner side of the finger spring 3 contacts the shielding layer 91 and part of the shielding wire of the shielding layer 91 is embedded in the finger spring 3, and the outer side of the finger spring 3 is pressed into contact with the inner annular groove 41. It also includes a metal shell 2 connected to the outer wall of the shielding ring 4 through an O-ring 5, a sealing ring 6, a clamping claw 7 and a tightening nut 8 connected in sequence to the front end of the metal shell 2, and a connecting nut assembly 1 connected to the rear end of the metal shell 2.

[0036] In the above structure, the cable grounding device consists of a shielding ring 4, a contact spring 3, an O-ring 5, a metal shell 2, a sealing ring 6, a clamping claw 7, a tightening nut 8, and a connecting nut assembly 1. All parts are arranged coaxially to perform the four functions of sealing, grounding, tensile strength, and docking with the housing in sequence.

[0037] The shielding ring 4 is a thin-walled cylinder with an outer annular groove 42 at its front end. An O-ring 5 is embedded in the outer annular groove 42, forming a rotatable sealing-conducting dual-function pair with the inner hole of the metal shell 2. The inner hole at the rear end has an inner annular groove 41, the width of which is slightly larger than the wire diameter of the contact spring 3. The contact spring 3 is pressed into the bottom of the groove with a set interference fit (e.g., 0.15–0.25 mm) to form a constant radial elastic force. The material can be brass plated with nickel and then silver, which balances mechanical strength and excellent conductivity.

[0038] The contact spring 3 can be a slanted coil spring with a free inner diameter smaller than the outer diameter of the cable 9. Each coil deforms independently to form parallel contact points. The inner side forms an embedded engagement with the outward-curving shielding layer 91 of the cable 9. When the shielding wire is inserted, it is micro-cut by the edge of the contact spring 3 and embedded in the gap, preventing axial slippage and ensuring 360° electrical continuity. The outer side has an interference fit with the shielding ring 4, forming a low-resistance grounding path. This allows the cable 9 to rotate slightly relative to the shielding ring 4 (e.g., ±10°) without the shielding layer 91 being stretched.

[0039] The metal casing 2 is a stepped cylinder, with its front external thread engaging with the tightening nut 8 and its rear external thread mating with the connecting nut assembly 1. The stepped hole at the front section accommodates the shielding ring 4, and an O-ring 5 is embedded in the outer annular groove 42 of the outer circumference of the shielding ring 4, forming a seal with the inner hole of the metal casing 2 and providing initial positioning. The metal casing 2 can be made of aluminum alloy, with overall hard anodizing and partial tin plating, balancing corrosion resistance and conductivity.

[0040] A sealing ring 6 and a clamping claw 7 are sequentially installed at the front end of the metal casing 2. A tightening nut 8 is connected to the external thread at the front of the metal casing 2. The tightening nut 8 secures the product through thread compression. The sealing ring 6 can be a double-lip structure with an inner diameter slightly smaller than the cable sheath, providing both waterproofing and rotational damping. The clamping claw 7 can be injection molded, with its front conical surface mates with the inner conical surface of the tightening nut 8. When tightened, the clamping claw 7 uniformly contracts to compress the cable sheath, achieving tensile strength. The tightening nut 8 can be made of aluminum alloy. During tightening, only the sealing ring 6, clamping claw 7, and cable sheath rotate; torque is not transmitted to the shielding ring 4, eliminating the risk of the shielding layer 91 breaking.

[0041] After passing through the shielding ring 4 and the metal shell 2, cable 9 is terminated by the connecting nut assembly 1. The connecting nut assembly 1 is screwed into the rear end of the metal shell 2. The internal interface can be configured as needed with a straight plug, thread, or bayonet, and it has a built-in double-sided toothed spring washer to ensure that there is no loosening under vibration.

[0042] In summary, the assembly process includes: stripping the cable 9 and turning the shielding layer 91 outward to the set length; passing the cable 9 through the tightening nut 8, clamping claw 7, and sealing ring 6; inserting the outward-turned shielding layer 91 into the shielding ring 4, where the shielding wire automatically embeds into the contact spring 3; pushing the shielding ring 4 along with the cable 9 into the metal housing 2 until a click is heard, indicating that the O-ring 5 is compressed and positioned; tightening the tightening nut 8, causing the clamping claw 7 to retract, thus securing the cable 9; and finally, tightening the connecting nut assembly 1 to the equipment housing. This completes the grounding of the entire machine in one step.

[0043] The cable grounding device provided by this utility model has a contact spring 3 installed in the inner annular groove 41 of the shielding ring 4. The shielding layer 91 of the cable 9 is folded outward and inserted into the shielding ring 4, and the contact spring 3 and the shielding layer 91 form direct contact. Due to the radial elastic force of the spring, part of the shielding wire is embedded in the gap of the spring ring, achieving stable engagement and ensuring stable contact. The contact spring 3 and the inner annular groove 41 are interference-fitted, while retaining rotational freedom. When the cable 9 rotates, the contact spring 3 moves synchronously to avoid the shielding wire being pulled and broken. During assembly, the continuous elastic force of the contact spring 3 locks the shielding ring 4 onto the cable 9 to prevent accidental detachment. At the same time, the contact spring 3 maintains elastic compression with the metal shell 2, resulting in low grounding impedance and vibration resistance. No secondary tightening or adjustment is required, and shielding conduction is achieved in one step, ensuring reliable grounding.

[0044] Based on the above specific embodiments, the inner annular groove 41 is a stepped groove, which can switch to install bushings of different diameters to match various specifications of finger springs 3, so as to achieve flexible adaptation to cables 9 of different diameters.

[0045] In some embodiments, in order to achieve diameter changes for the full range of cables from 4mm² to 50mm² within a single shielding ring 4, the traditional single straight groove is replaced with a stepped groove, and a three-level nested structure of replaceable bushings and contact springs 3 is introduced, which ensures electrical continuity and reduces the variety of materials required.

[0046] The stepped groove consists of an outer groove and an inner groove. The diameter of the outer groove is larger than that of the inner groove, but their widths are equal. The outer groove is used to directly accommodate large-diameter contact springs 3, such as those covering 25–50 mm² cables. The inner groove is used to embed removable bushings, forming small-diameter inserts to support medium and small-diameter contact springs 3. Both the bottom ends of the outer and inner grooves are rounded to avoid stress concentration at the edges of the bushings or contact springs 3. The groove wall roughness is moderate to ensure a stable and reliable interference fit with the bushing, without axial movement.

[0047] Two bushings are provided to cover the entire range: the medium bushing is suitable for medium-sized contact springs for 10–25mm² cables; the small bushing is suitable for small-sized springs for 4–10mm² cables.

[0048] The bushing has a thin wall thickness, such as 0.4–0.6 mm, without increasing the overall outer diameter, and its height is equal to the width of the outer groove; the outer diameter is interference-fitted with the corresponding stepped groove; the inner diameter is graded according to the outer diameter of the touch finger spring. The material is beryllium copper plated with silver, which balances high elasticity and low resistance; two plug-in notches can be provided at the tail, which can be quickly installed and removed by hand.

[0049] The metal outer shell 2, shielding layer 91, stepped groove, bushing, and contact spring 3 are all concentric, ensuring a continuous, low-resistance shielded circuit for all cable sizes from 4mm² to 50mm². The same shielding ring 4 can be used interchangeably with existing stock, and only two types of low-cost bushings are needed to match various sizes of contact spring 3, enabling rapid compatibility switching between large, medium, and small diameter cables, significantly reducing the variety of materials and production costs.

[0050] Based on the above specific embodiments, a metal adjusting ring connected in the inner annular groove 41 is also included. The outer side of the metal adjusting ring contacts the inner annular groove 41, and the inner side of the metal adjusting ring is in compression contact with the outer side of the touch finger spring 3. The inner diameter of the metal adjusting ring can be radially contracted and adjusted to match various specifications of touch finger springs 3.

[0051] In some embodiments, a metal adjusting ring is placed between the inner annular groove 41 and the contact spring 3, serving as a radially retractable elastic intermediate layer. By elastically adjusting its inner diameter, the fixed structure of one groove and one spring is upgraded to a universal structure of one groove and multiple springs, which reduces the requirements for part machining accuracy and ensures long-term low-resistance contact.

[0052] The metal adjusting ring can be an open ring or a C-shaped ring, with multiple S-shaped or Ω-shaped shrinkage ribs evenly distributed around its circumference to provide controllable radial travel. A pair of radial fine-tuning lugs are provided at the open end; a light pressure allows for overall diameter reduction, which can be operated by hand. The metal adjusting ring can be based on brass or beryllium copper, with a nickel-plated and silver-plated surface, combining high elasticity, high conductivity, and corrosion resistance. The outer side is a smooth cylindrical surface that fully fits the inner annular groove 41; the inner side has multiple pressure contact points on the spring 3 to avoid the risk of pitting corrosion.

[0053] The metal adjusting ring pushes outward against the bottom of the inner annular groove 41 and wraps inward around the contact spring 3, forming three large-area transition conductors: the inner annular groove 41, the metal adjusting ring, and the contact spring 3. This significantly reduces contact resistance and temperature rise. The metal adjusting ring has its own springback, which can absorb dimensional drift caused by thermal expansion and contraction and vibration, maintaining interference fit over a long period of time.

[0054] During assembly, first press the metal adjusting ring into the inner annular groove 41, and then install the target specification contact spring 3. During maintenance, when replacing the contact spring 3, there is no need to remove the shielding ring 4. Simply remove the old contact spring 3, adjust the inner diameter of the metal adjusting ring, and press in the new contact spring 3 to achieve immediate replacement.

[0055] The metal adjusting ring can adaptively match. When the outer diameter of the contact spring 3 is too large, it can be pressed in directly, and the metal adjusting ring will automatically open, matching the interference in real time. When the outer diameter of the contact spring 3 is too small, the pre-compression fine-tuning ear will reduce the inner diameter before it is installed, still maintaining an appropriate interference.

[0056] The shielding ring 4 and the inner annular groove 41 only need to be machined once, without secondary processing or mold opening according to specifications; the same inner annular groove 41 can be adapted to the contact spring 3 with different wire diameters and different free outer diameters, covering a variety of cable cross sections; only one type of metal adjusting ring is needed in the inventory, which can replace multiple sets of special groove types, greatly reducing material preparation and management costs.

[0057] Based on the above specific embodiments, the metal adjusting ring includes an inner ring, an outer ring, and an elastic element connecting the inner ring and the outer ring. The elastic element is evenly distributed in the circumferential direction of the inner ring. The elastic element contracts radially along the inner annular groove 41, and the inner ring can contract circumferentially. The inner side of the inner ring is in contact with the outer side of the finger spring 3, and the outer side of the outer ring is in contact with the inner annular groove 41.

[0058] In some embodiments, the metal adjusting ring adopts a three-layer coaxial nested structure of outer ring, elastic element and inner ring, which is embedded in the inner annular groove 41 of the shielding ring 4 to form a radially retractable elastic clamping unit, upgrading the single-size inner annular groove 41 into a universal interface compatible with multiple specifications of finger springs 3.

[0059] The outer ring is a rigid circular ring with an interference or light press fit between the outer cylindrical surface and the bottom of the inner annular groove 41. It does not move after installation and serves as both a reference and a conductive path. The outer surface is mirror polished to reduce insertion resistance and wear.

[0060] The inner ring is a thin-walled ring, and its inner diameter directly encircles the finger spring 3. By means of the radial deformation of the elastic element, a large range of continuous diameter reduction / expansion is achieved to ensure a close fit with finger springs 3 of different outer diameters.

[0061] The root of the elastic element is fixed to the outer ring, and the top connects to the inner ring, providing both elastic force and forming a conductive bridge. Multiple elements, such as 3 to 10, are evenly distributed circumferentially and arranged symmetrically to ensure balanced stress in all directions and prevent uneven wear. Either columnar springs or sheet springs can be used; miniature disc springs or wave springs can be added inside the sheet springs to achieve precise preload compensation. The elastic force of the elastic element is constant, maintaining low-resistance contact and reliable clamping over a long period.

[0062] During assembly, the metal adjusting ring is pressed into the inner annular groove 41, and the outer ring is fixed as the reference. The contact spring 3 is pushed in, and the elastic element is compressed to generate a set radial elastic force, and the inner ring and the contact spring 3 form a stable interference fit.

[0063] When changing cables, loosen the clamping nut 8, pull out the cable 9, and insert the new specification cable. When changing the contact spring 3, simply pull out the old contact spring 3 and insert the new specification cable. During the process of changing cables and contact spring 3, the inner ring automatically contracts / expands with the elastic element, and can spring back to position without tools to maintain the required interference fit; the entire process does not require disassembling the grounding device, achieving quick replacement with a simple loosening and inserting motion.

[0064] As can be seen from the above, a set of metal adjusting rings can be adapted to various cable diameters and contact spring specifications, significantly reducing material preparation, processing and maintenance costs.

[0065] Based on the above specific embodiments, the inner ring includes at least two arc-shaped segments that are connected at the ends, so as to adjust the diameter of the inner ring to achieve the squeezing contact between the inner side of the inner ring and the outer side of the finger spring 3.

[0066] In some embodiments, the inner ring is a stepless ring formed by inserting multiple (e.g., 2-4) arc-shaped segments end to end, with each segment having an arc length of 60° to 180°. One end of each arc-shaped segment is a male end, equipped with a thin tongue with a slight chamfer and a thickness less than or equal to the arc-shaped segment body to ensure smooth insertion. The other end of each arc-shaped segment is a female end, equipped with a dovetail groove or T-shaped groove, etc., with a groove depth greater than or equal to the tongue thickness and a side clearance to prevent dislodgement and jamming. The arc-shaped segments are slidably connected by the tongue and the groove, allowing adjacent arc-shaped segments to transmit circumferential force while allowing radial misalignment, enabling continuous fine-tuning of the diameter. The arc-shaped segments are detachably connected; if any segment is worn or broken, simply remove the faulty arc-shaped segment and insert a new one; the remaining arc-shaped segments can continue to be used, resulting in low maintenance costs and short downtime. Optionally, the groove has a raised rib, and the tongue corresponds to the groove, producing a "click" feeling when pushed in, facilitating blind operation on site.

[0067] The inner ring diameter is easy to adjust. Pulling each arc segment outward slightly shortens the insertion length and increases the inner ring diameter. Pressing inward slightly or using the radial force of the elastic element causes the arc segments to shrink radially, increasing the insertion length and decreasing the inner ring diameter.

[0068] During assembly, according to the cable 9 specification, the inner diameter of the inner ring is pre-adjusted to be slightly smaller than the outer diameter of the target contact spring 3; after the shielding layer 91 is flipped outward, it is inserted, and the shielding wire is gripped by the contact spring 3; the arc section elastically rebounds, and the radial surface presses and locks the contact spring 3 and protects the shielding wire from overvoltage damage.

[0069] The diameter adjustment corresponding to the insertion length of each arc segment of the inner ring is sufficient to cover the outer diameter of common finger springs 3, thus making it compatible with cables 9 of different wire diameters; multi-segment linkage can enlarge or shrink across the entire circumference, forming a truly stepless adjustment.

[0070] Based on the above specific embodiments, the arc segment is an elastic metal sheet used to adapt to the outer contour of the finger spring 3.

[0071] In some embodiments, the entire arc-shaped segment is made of beryllium copper, which, after solution treatment and aging, possesses high conductivity, high resilience, and corrosion resistance. After the arc-shaped segment is inserted, the entire ring maintains an inward radial force, forming a uniform and continuous circumferential compression. The diameter of the arc-shaped segment is slightly smaller than the free outer diameter of the finger spring 3, generating elastic preload after assembly to ensure continuous low resistance.

[0072] Preferably, the arc-shaped segment has slits on both sides, and the ends of the slits are rounded to form a corrugated spring-like yielding structure; it can be slightly stretched when subjected to radial force, adapting to the slight unevenness of the surface of the touch spring 3 and the tolerance of the wire diameter.

[0073] Based on the above specific embodiments, the cross-sectional profile of the inner ring is consistent with the outer profile of the contact spring 3. If the contact spring 3 is an elliptical spring, the inner side of the inner ring is an elliptical arc with the same curvature; if it is a C-shaped spring, the inner side of the inner ring is a C-shaped arc surface with the same opening angle. The curvature radius tolerance of the arc segment is controlled within the set range to ensure 360° fit; the contact band width is relatively wide to achieve low resistance and uniform pressure distribution.

[0074] The cross-sectional profile of the outer ring is consistent with that of the inner annular groove 41. When the inner annular groove 41 is a rectangular groove, the outer side of the outer ring is a rectangular step of the same width and depth. If the inner annular groove 41 is a dovetail or trapezoid, the outer side of the outer ring is also machined into a dovetail or trapezoid of the same shape with the same angle and size. After the outer ring is installed, it is positioned without gaps, which both transmits torque and maintains electrical continuity.

[0075] Preferably, the inner and outer rings are CNC machined from the same piece of high-conductivity copper alloy. The outer ring shape is machined first; the inner cavity is precision bored with the inner ring contour as a reference when changing tools; the concentricity is kept consistent throughout the process, the cross-section is consistent and there are no abrupt changes in the circumference, and local stress concentration and contact resistance fluctuations are eliminated.

[0076] Based on the above specific embodiments, the metal adjusting ring is a complete circular leaf spring, formed by one-time stamping of a high-elasticity beryllium copper sheet. It has a U-shaped or C-shaped thin-walled ring band with a thickness of 0.2–0.3 mm, and its inner and outer edges are coaxial to ensure circumferential accuracy.

[0077] Multiple radial slits are punched at equal intervals along the circumference of the entire ring, dividing the ring into several parallel elastic spokes. The entire ring thus possesses overall radial contraction-rebound capability, preserving the ring's rigidity while achieving uniform elastic deformation.

[0078] The inner arc-shaped cutting edge of the leaf spring is directly clamped around the outer circumference of the contact finger spring 3, utilizing the elastic restoring force of the leaf spring to provide continuous, full-circumferential radial pressure, causing the shielding wire to be pressed into the contact finger at multiple points. The outer side is interference-fitted with the inner annular groove 41 of the shielding ring 4, serving as both a conductive bridge and a positioning reference.

[0079] When the diameter of cable 9 is changed or the contact spring 3 is replaced, simply use calipers or a special expander to pry the leaf spring outwards to easily slide in or remove the contact spring 3; after releasing the tool, the leaf spring automatically springs back and relocks, without the need for additional parts.

[0080] The entire leaf spring serves as both an adjusting element and a conductive bridge, featuring a simple structure and few parts. It can provide uniform and repeatable radial clamping force throughout the circumference, is compatible with contact springs 3 of different outer diameters, and matches cables 9 of different wire diameters, ensuring multi-point, low-resistance, and vibration-resistant electrical connections.

[0081] Based on the above specific embodiments, the inner wall of the contact spring 3 that directly contacts the shielding layer 91 of the cable 9 is provided with serrations. This is used to pierce the oxide film while avoiding cutting the wires when in direct contact with the shielding layer 91 of the cable 9, thereby achieving a low-resistance, highly reliable multi-point electrical connection. Preferably, the ends of the serrations are rounded. The rounded ends prevent sharp edges from cutting the shielding wires, while allowing the braided layer to have a slight elastic yield under radial compression, preventing stress concentration.

[0082] When the outward-facing shielding layer 91 is inserted into the contact spring 3, the serrations contact the shielding layer 91. The serrations first slightly penetrate the oxide film to reduce the contact resistance. The serrations then hook onto the shielding wire and press it into the gap of the contact spring 3, producing local plastic deformation and forming a micro-cold welded metal-metal contact, which further improves the conductivity reliability and provides mechanical locking force against torsion and pull-out.

[0083] Based on the above specific embodiments, the shielding ring 4 is provided with multiple parallel inner annular grooves 41 along the axial direction, and the cable 9 and the shielding ring 4 are connected by multiple finger springs 3.

[0084] In some embodiments, the shielding ring 4 hole wall is provided with multiple inner annular grooves 41 along the axial direction. Specifically, 2 to 4 parallel inner annular grooves 41 can be machined at equal intervals to form a multi-ring parallel structure. Each inner annular groove 41 is embedded with an independent, same-specification contact finger spring 3, forming a multi-inner-ring-multi-contact finger parallel grounding unit.

[0085] The center distance between adjacent inner annular grooves 41 is moderate, such as 3.5–4 mm, balancing axial compactness with heat dissipation space. The bottom of the grooves is rounded to eliminate stress concentration. The inner diameter of the contact spring 3 is slightly smaller than the outer diameter of the shielding layer 91 of the cable 9, ensuring multi-point engagement.

[0086] During assembly, the outer sheath of the cable is removed, and the shielding layer 91 is turned outward into a continuous cylindrical shape; it is pushed past the first, second...Nth contact finger spring 3 in sequence; each time it passes through a ring, the shielding wire is bitten and partially embedded by the serrations of that ring; finally, the shielding layer 91 is surrounded by multiple independent contact fingers in the axial direction, forming a multi-point, low-resistance, low-inductance leakage path, and the contact area increases linearly with the number of rings.

[0087] The total contact resistance is reduced to 1 / N of that of the single-ring scheme, and the current carrying capacity increases exponentially with the number of rings; multiple rings disperse current and heat, and the temperature rise at a single point is significantly reduced; multiple rings enhance the resistance to shock and pull-out; if any contact spring 3 fails, the rest still maintain a complete grounding path, resulting in high system redundancy.

[0088] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0089] The cable grounding device provided by this utility model has been described in detail above. Specific examples have been used to illustrate the principle and implementation of this utility model. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core idea of ​​this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made to this utility model without departing from the principle of this utility model, and these improvements and modifications also fall within the protection scope of the claims of this utility model. Therefore, this utility model is not limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A cable grounding device, characterized in that, The device includes a shielding ring (4) with an inner annular groove (41) on its inner side, and a finger spring (3) fitted inside the inner annular groove (41). After the shielding layer (91) of the cable (9) is turned outward and inserted into the shielding ring (4), the inner side of the finger spring (3) contacts the shielding layer (91) and part of the shielding wire of the shielding layer (91) is embedded in the finger spring (3). The outer side of the finger spring (3) is pressed against the inner annular groove (41). The device also includes a metal shell (2) connected to the outer wall of the shielding ring (4) through an O-ring (5), a sealing ring (6), a clamping claw (7) and a tightening nut (8) connected in sequence to the front end of the metal shell (2), and a connecting nut assembly (1) connected to the rear end of the metal shell (2).

2. The cable grounding device according to claim 1, characterized in that, The inner annular groove (41) is a stepped groove, which can be switched to install bushings of different diameters to match the finger springs (3) of various specifications.

3. The cable grounding device according to claim 1, characterized in that, It also includes a metal adjusting ring connected in the inner annular groove (41), the outer side of the metal adjusting ring is in contact with the inner annular groove (41), the inner side of the metal adjusting ring is in extrusion contact with the outer side of the finger spring (3), and the inner diameter of the metal adjusting ring can be radially contracted to match the finger spring (3) of various specifications.

4. The cable grounding device according to claim 3, characterized in that, The metal adjusting ring includes an inner ring, an outer ring, and an elastic element connecting the inner ring and the outer ring. The elastic element is evenly distributed in the circumferential direction of the inner ring. The elastic element contracts radially along the inner annular groove (41). The inner ring can contract circumferentially. The inner side of the inner ring is pressed against the outer side of the finger spring (3). The outer side of the outer ring is in contact with the inner annular groove (41).

5. The cable grounding device according to claim 4, characterized in that, The inner ring includes at least two arc-shaped segments that are inserted at the ends, so as to adjust the diameter of the inner ring to achieve the inner side of the inner ring to press against the outer side of the finger spring (3).

6. The cable grounding device according to claim 5, characterized in that, The arc-shaped segment is an elastic metal sheet used to adapt to the outer contour of the finger spring (3).

7. The cable grounding device according to claim 4, characterized in that, The cross-sectional profile of the inner ring is consistent with the outer profile of the finger spring (3), and the cross-sectional profile of the outer ring is consistent with the cross-sectional profile of the inner annular groove (41).

8. The cable grounding device according to claim 3, characterized in that, The metal adjusting ring is a circular leaf spring. The inner side of the leaf spring is in contact with the outer side of the finger spring (3), and the outer side is in contact with the inner annular groove (41). The leaf spring contracts radially along the inner annular groove (41).

9. The cable grounding device according to claim 1, characterized in that, The inner wall of the finger spring (3) is provided with serrations, and the serrations are in contact with the shielding layer (91).

10. The cable grounding device according to claim 1, characterized in that, The shielding ring (4) has multiple parallel inner annular grooves (41) along the axial direction, and the cable (9) and the shielding ring (4) are connected by multiple finger springs (3).

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