A car-grade single-core via-hole shielding connector

Abstract

The application provides a vehicle gauge level single-core via shielding connector, and belongs to the technical field of new energy vehicles. The connector comprises a shell assembly, an O-ring, a shielding ring, a sealing line body and a tail cover. The shell assembly is integrally formed by a metal mounting head and a plastic shell through injection molding. The shielding ring is a seamless metal component integrally formed by drawing, and is sequentially provided with a crimping cylinder body, a stress isolation groove, a positioning step portion and an annular contact portion with a spherical convex bump in the axial direction. The application uses a shielding ring structure with a seamless stress isolation groove to eliminate the risk of crimping cracking and deformation interference, uses a C-shaped slot cooperating with a spherical convex bump structure to realize reliable shielding against vibration, and uses a positioning step to realize axial stopping of a cable. In addition, the tail cover B adopts a whole injection molded movable hinge and a double buckle structure, cooperates with a special deformation groove and an anti-rebound slope to realize stable clamping and anti-loosening of the corrugated pipe. The application has the characteristics of high vibration resistance, high sealing and convenient assembly.

Description

Technical Field

[0001] This invention relates to the field of high-voltage connection system technology for new energy vehicles, specifically to an automotive-grade single-core through-hole shielded connector. Background Technology

[0002] As the voltage platform of electrical systems in new energy vehicles moves towards 800V or even higher, the electromagnetic shielding performance of high-voltage connectors is one of the important factors affecting the safety of the entire vehicle. In existing single-core through-hole shielded connector designs, a metal shielding ring structure is usually used to achieve the conduction of the shielded circuit.

[0003] For example, Chinese invention patent application publication number CN110190451A discloses a connector and its shielding sleeve assembly. The technical solution includes a metal shielding sleeve, on the front circumference of which are provided multiple outwardly folded elastic cantilever arms for elastic contact with the inner wall of the outer shell; its rear end is fixed to the cable shielding layer by pressing.

[0004] However, in actual automotive-grade applications, especially in the harsh vibration conditions described in GB / T38661-2020, this cantilever beam contact structure has revealed significant limitations:

[0005] High-frequency vibration failure: The cantilever beam structure is essentially a spring oscillator with a specific natural frequency. When the random vibration frequency generated by vehicle movement overlaps with the natural frequency of the cantilever beam, resonance occurs, causing repeated micron-level slippage and wear at the contact points, producing oxide debris. This leads to a sharp increase in contact resistance and a significant decrease in shielding effectiveness.

[0006] Crimping deformation interference: In the existing technology, the shielding sleeve is usually an integral thin-walled cylinder. When the hexagonal crimping operation is performed on the crimping area at the rear end, the plastic flow and deformation stress of the metal are easily transmitted to the contact area at the front end, causing the roundness of the front end to be distorted, making some of the spring arms unable to make effective contact, resulting in shielding leakage.

[0007] Weak axial tensile strength: It often relies on the friction of the external plastic nut to resist the strong axial pull of the cable. After long-term use, it is easy to loosen the fixation due to plastic creep. Summary of the Invention

[0008] Purpose of the invention: To overcome the shortcomings of existing technologies, a connector with high vibration resistance, low contact resistance and high tensile strength is designed.

[0009] Technical Solution: An automotive-grade single-core through-hole shielded connector includes an O-ring, a housing assembly, a shielding ring, a sealing body, and a tail cap; the housing assembly includes a metal mounting head and a plastic housing injection-molded overlying the metal mounting head, and the threaded end of the housing assembly has an annular groove; the O-ring is installed in the annular groove to achieve a sealed and waterproof connection at the connector mounting interface; the sealing body is installed on one side of the shielding ring and abuts against the tail cap for sealing and buffering the cable tail; the tail cap is fitted over the cable and secured by fastening with the housing assembly.

[0010] As a core improvement of the present invention, the shielding ring is a seamless cylindrical structure formed by multiple drawing processes of metal strip, and it is provided with a pressing cylinder, stress isolation groove, positioning step and annular contact part in sequence along the axial direction.

[0011] The crimping cylinder is fixed to the outward-facing shielding layer of the cable by plastic deformation crimping, with the aim of achieving low-resistance electrical conduction and mechanical connection between the shielding ring and the cable.

[0012] The stress isolation groove is disposed between the pressing cylinder and the positioning step, and is a circumferential annular necked or thin-walled structure. Its function is to block the plastic flow stress generated by the pressing cylinder during large deformation pressing from being transmitted to the front end, and to prevent the positioning step and the annular contact part from warping or becoming out of round due to stress transmission, thereby ensuring the accuracy of the contact dimensions.

[0013] The positioning step extends radially outward to form an abutment surface. The inner wall of the metal mounting head is provided with a corresponding blocking step. The positioning step and the blocking step cooperate to form an axial stop structure, which aims to directly bear the axial pull-out force on the cable by utilizing the rigid mechanical interference between the metals, preventing the internal terminals from dislodging under force, and significantly improving the tensile strength of the connector.

[0014] The annular contact portion has several C-shaped grooves, which surround and form an outwardly protruding elastic contact tongue. The elastic contact tongue maintains an interference fit with the inner wall of the metal mounting head by utilizing the elastic deformation capacity of the C-shaped groove root. This design utilizes the high geometric stiffness and contact stress of the spherical convex hull to pierce the oxide layer on the metal surface. Moreover, the natural frequency of the spherical structure is much higher than the vibration frequency of vehicle travel, thereby avoiding the resonance and fretting wear problems that are prone to occur in traditional cantilever beam structures, and ensuring the stability of the shielding effectiveness throughout the entire life cycle.

[0015] An annular reinforcing flange extends from one end of the annular contact portion away from the positioning step portion; the annular reinforcing flange is an arc-shaped structure formed by rolling inward or outward in the radial direction, which is used to enhance the circumferential stiffness of the port of the annular contact portion and maintain the roundness of the annular contact portion.

[0016] Furthermore, the tail cap can be either tail cap A or tail cap B to adapt to different wiring harness protection requirements. Tail cap B is specifically designed for connecting the bellows, and its first snap-fit ​​groove has a fastener connected to its outer wall via a one-piece injection-molded movable hinge. This movable hinge design avoids the problem of easily lost snap-fit ​​parts and simplifies the mold opening and assembly process. The inner wall of tail cap B is provided with a first limiting rib, and the inner wall of the fastener is provided with a second limiting rib; both work together to engage with the trough position of the bellows. The purpose of these limiting ribs is to axially lock the bellows, preventing it from slipping off during vehicle vibrations.

[0017] Furthermore, the outer surface of the metal mounting head is provided with an anti-rotation groove and an axial limiting groove, which are filled with injection-molded material of the plastic shell. This interlocking structure is designed to enhance the shear resistance of the metal-plastic interface and prevent the two from peeling or loosening due to the difference in thermal expansion coefficients during thermal shock cycles.

[0018] The number of elastic contact tongues can be adjusted from 2 to 20 depending on the connector size. To balance contact stability and manufacturing process, 6 to 8 tongues are preferred, evenly distributed or arranged in an array along the circumference of the annular contact portion. The protrusions of the elastic contact tongues face radially outward. The shielding ring and housing assembly are sized to accommodate cables with a cross-sectional area ranging from 25 mm² to 150 mm². The external thread specifications of the metal mounting head include, but are not limited to, standard metric threads of M16, M25, M32, and M36.

[0019] Invention principle: In view of the problems of easy resonance wear of cantilever beam contacts and the impact of crimping deformation on contact reliability in the prior art, the present invention replaces the cantilever beam contact with a spherical convex high-stress contact and introduces a stress isolation groove structure. While completely eliminating the risk of resonance, it blocks the transmission of crimping stress. Combined with a unique stepped stop design, it achieves a comprehensive performance improvement of high vibration resistance, low contact resistance and high tensile strength.

[0020] Beneficial effects:

[0021] 1. Excellent vibration shielding performance: It abandons the open cantilever beam spring with cut-off end face and adopts a rigid cylinder + spherical convex hull design. Combined with the stress isolation groove to ensure the roundness, the connector has a contact resistance change rate of <5mΩ and no instantaneous disconnection phenomenon in the stringent random vibration test required by GB / T38661.

[0022] 2. High manufacturing process reliability: The unique stress isolation groove design solves the common problem in the industry of front-end deformation caused by pressing, which greatly improves the product yield and eliminates the need for complicated calibration procedures.

[0023] 3. Automotive-grade tensile strength: The shielding ring itself has metal steps for axial stop, which increases the cable's pull-out force to over 150N, far exceeding the 80N level of conventional plastic locking structures. This solves the problem of cable detachment and meets the safety standards for high-voltage wiring harnesses.

[0024] 4. High tensile strength and reliability: The rigid mechanical stop formed by the positioning step in the middle of the shielding ring and the metal shell enables the connector to withstand the axial tensile force of the cable exceeding the national standard requirements, preventing the terminal from dislodging and ensuring the safety of the vehicle.

[0025] 5. Versatility and Flexibility: The modular optional tail cap design allows the same main structure to be adapted to bare wire or corrugated pipe protection, thereby significantly improving the versatility and adaptability of the parts; this structure can simplify the assembly process by reducing special adapters and repetitive processes, reducing the types of parts and inventory pressure, and reducing the number of electrical connection interfaces actually needed, thereby greatly improving the overall reliability of the system and reducing production costs. Attached Figure Description

[0026] Figure 1 This is an assembly diagram of the single-core through-hole shielded connector structure using tail cap A in Embodiment 1 of the present invention;

[0027] Figure 2 for Figure 1 Assembly drawing of the inner and outer shell components;

[0028] Figure 3 for Figure 1 Schematic diagram of the middle shielding ring;

[0029] Figure 4 yes Figure 3 A sectional view in the assembled state;

[0030] Figure 5 This is an assembly diagram of the single-core through-hole shielded connector structure using tail cap B in Embodiment 2 of the present invention;

[0031] Figure 6 for Figure 5 A schematic diagram of the installation of the tail cap B and the bellows.

[0032] Figure 7 for Figure 6 A schematic diagram of the structure;

[0033] Figure 8 for Figure 7 CC cross-section view.

[0034] In the diagram: 1. O-ring; 2. Housing assembly; 21. Metal mounting head; 211. Anti-rotation groove; 212. Axial limiting groove; 22. Plastic housing; 3. Terminal; 4. Shielding ring; 41. Stress isolation groove; 42. Spherical protrusion; 43. C-shaped groove; 5. Sealing body; 6. Tail cap A; 7. Cable; 8. Tail cap B; 81. Second snap-fit ​​groove; 811. Anti-rebound slope; 82. First snap-fit ​​groove; 83. First snap; 84. Second snap; 841. Deformation groove; 85. Second limiting rib; 9. Corrugated pipe. Detailed Implementation

[0035] The technical solution of the present invention will be further described in detail below with reference to specific embodiments.

[0036] Example 1

[0037] Reference Figure 1 and Figure 2 As shown, the automotive-grade single-core through-hole shielded connector in this example includes an O-ring 1, a housing assembly 2, a terminal 3, a shielding ring 4, a sealing body 5, and a tail cap.

[0038] The screw thread end of the housing assembly 2 is provided with an annular groove. The housing assembly 2 is integrally formed by in-mold injection molding of the metal mounting head 21 and the plastic housing 22. The O-ring 1 is installed in the annular groove at the screw thread end of the housing assembly 2. When the connector is inserted into the reserved mounting hole of the equipment, the O-ring 1 is compressed, thereby achieving a sealing and waterproof function. The shielding ring 4 is pressed onto the outer wall of the cable 7 and placed inside the housing assembly 2.

[0039] like Figure 3 and Figure 4As shown, the shielding ring 4 is integrally drawn from metal strip, forming a seamless cylindrical structure. Although the annular contact portion is based on a seamless drawn cylindrical body, to enhance adaptability to different tolerance fits and ensure contact pressure, this embodiment forms six C-shaped grooves 43 on the circumferential wall of the annular contact portion through a precision punching process. These grooves are evenly distributed circumferentially. The C-shaped grooves 43 do not cut off the front edge of the annular contact portion, thus preserving the complete end-face reinforcing ring. Compared to the completely cut open cantilever beam in the prior art, the structure of this invention has higher strength. An elastic contact tongue is formed inside the C-shaped groove 43, and a spherical protrusion 42 is stamped on the free end of each elastic contact tongue. When the metal mounting head 21 is inserted, the elastic contact tongue experiences a slight rebound due to the material elasticity at the root of the groove, and the contact stress of the spherical protrusion 42 achieves an elastic interference fit with the inner wall of the metal mounting head 21 in the housing assembly 2. This achieves a reliable low-resistance electrical connection under vibration conditions. A positioning step and a stress isolation groove 41 are provided in the middle section of the shielding ring 4. The crimping cylinder is located at the rear end and is crimped with the shielding layer of the cable 7 to achieve electrical connection. The stress isolation groove 41 prevents the transmission of rear-end crimping deformation to the front end, while the positioning step cooperates with the metal mounting head 21 to achieve axial stop. Finally, a complete shielding circuit is achieved through the contact between the metal mounting head 21 in the housing assembly 2 and the device housing. This seamless cylinder + partial C-shaped cantilever structure design not only ensures the overall roundness through the seamless cylinder, but also provides a stable normal contact force through the C-shaped groove, effectively solving the problem of instantaneous breakage that may occur in rigid contacts under severe vibration.

[0040] Furthermore, to address the potential decrease in port strength after slotting, this embodiment employs an integrally formed annular reinforcing flange at the foremost end of the shielding ring 4. The technical function of this structure is:

[0041] First, geometric stiffening: The flanged structure significantly increases the moment of inertia of the port section, forming a rigid reinforcing ring. Even with C-shaped grooves in the ring body, this reinforcing ring can effectively resist radial external forces, prevent the port from undergoing elliptical deformation under pressure, and ensure the roundness of the overall structure.

[0042] Second, non-destructive assembly: The smooth R-angle formed by the flange naturally constitutes the guide and introduction surface. When the shielding ring 4 is inserted into the housing assembly 2, this smooth surface can automatically correct minor alignment deviations and avoid the sharp stamping burrs of traditional straight-cut ports scratching the silver / nickel plating on the inner wall of the metal mounting head 21, thereby ensuring the corrosion resistance of the contact interface.

[0043] The sealing body 5 is installed on one side of the shielding ring 4 and abuts against the tail cap. After being axially pressed by the tail cap, the outer circumferential surface of the sealing body 5 fits against the inner wall of the outer shell assembly 2, thereby covering and sealing the outer wall of the cable 7. The sealing body 5 ensures the sealing and waterproof performance between the cable 7 and the outer shell assembly 2.

[0044] The end cap is fitted over the cable 7 and secured by fastening with the outer casing assembly 2. As a further embodiment of the invention, the end cap is designated as end cap A6. End cap A6 has a straight-through structure and does not engage with the corrugated tube; it is primarily used for sealing bare wires. After being pushed forward along the cable 7, end cap A6 abuts against the sealing body 5 and is secured to the outer casing assembly 2 by fastening, generating axial pre-tightening force in the sealing body 5, thereby completing the sealing and protection of the cable 7.

[0045] As a further embodiment of the present invention, the outer casing assembly 2 includes a metal mounting head 21 and a plastic outer casing 22. The outer surface of the metal mounting head 21 is provided with an anti-rotation groove 211 and an axial limiting groove 212 for limiting its positioning within the plastic outer casing 22. The plastic outer casing 22 covers the outside of the metal mounting head 21, and the two are integrally formed by in-mold injection molding. The anti-rotation groove 211 and the axial limiting groove 212 are used to achieve rotational and axial positioning between the metal and the plastic during the in-mold injection molding process, preventing them from loosening.

[0046] Working principle: After the tail cap A6 and the sealing body 5 are sequentially placed on the cable 7, the crimping cylinder at the rear end of the shielding ring 4 is forcefully crimped to the shielding wire of the cable 7 using a hexagonal mold, and then the terminal 3 is crimped. After the cable 7 assembly is inserted into the outer shell assembly 2, the positioning step of the shielding ring 4 is in place, and then the tail cap A6 is fastened for installation and fixation. Then, the O-ring 1 is installed in the annular groove at the end of the thread of the outer shell assembly 2, and then inserted into the pre-drilled mounting hole of the equipment. The O-ring 1 is compressed, thereby achieving the sealing and waterproof function.

[0047] Example 2

[0048] Reference Figure 5 , Figure 6 , Figure 7 and Figure 8 As a further embodiment of the present invention, the tail cover is configured as tail cover B8. Tail cover B8 can be snapped into the bellows 9. The outer wall of tail cover B8 is provided with a second snap-fit ​​groove 81 and a first snap-fit ​​groove 82. The outer wall of the first snap-fit ​​groove 82 is hinged to a fastener by an integrally injection-molded movable hinge (flip hinge).

[0049] As a further embodiment of the present invention, a first buckle 83 is provided at one end of the fastener near the first buckle groove 82, and a second buckle 84 is provided at the other end of the fastener. The first buckle 83 and the second buckle 84 are respectively snapped into the first buckle groove 82 and the second buckle groove 81 on the tail cap B8 to fix the bellows 9 to the outer shell assembly 2, forming a stable fastening structure and preventing the bellows 9 from axially loosening during use.

[0050] As a further embodiment of the present invention, the inner wall of the tail cap B8 is provided with a first limiting rib, and the inner wall of each fastener is provided with a second limiting rib 85, for engaging the bellows 9 and cooperating with the outer wall structure of the bellows 9 to achieve fixation. The limiting ribs fit into the corrugated grooves on the outer wall of the bellows 9, so that the bellows 9 is stably constrained in both the axial and radial directions, improving the mechanical fixing strength. Specifically, the first limiting rib located in the body of the tail cap B8 plays a role in bottom support and limiting, while the second limiting rib 85 located in the inner wall of the fastener plays a role in top pressing and limiting.

[0051] As a further improvement in this invention, in order to optimize the operating feel and connection reliability, a deformation groove 841 is provided at the root of the second buckle 84, which is used to generate elastic deformation when fastened, so that the buckle action is smoother; the inner wall of the second buckle groove 81 is provided with an anti-rebound slope 811, which can effectively prevent the fastener from loosening under vibration or external force disturbance, further improving the connection reliability.

[0052] Working principle: First, insert cable 7 into corrugated tube 9. Then, successively place end cap B8 and sealing body 5 onto cable 7. Secure corrugated tube 9 onto the first limiting rib of end cap B8 and perform subsequent fastening operations. Finally, sequentially crimp shielding ring 4 to the shielding wire crimping point of cable 7 and crimp terminal 3. After cable 7 is inserted into the outer casing assembly, fasten end cap B8 to secure it in place.

[0053] The specific operational details for fixing the bellows 9 to the tail cap B8 are as follows: Secure the bellows 9 to the first limiting rib on the inner wall of the tail cap B8, ensuring the last two teeth of the bellows 9 are engaged. Using the movable hinge (flip hinge), rotate the second clip 84 of the fastener 180 degrees, allowing it to engage in the second clip groove 81. During this process, the first clip 83 also engages in the first clip groove 82, and the second limiting rib 85 on the fastener also engages in the groove of the bellows 9, forming a complete enclosure and fixation of the bellows tail.

[0054] During this fastening process, due to the deformation groove 841 at the base of the second snap fastener 84, the base of the second snap fastener 84 will first undergo a slight backward deformation under force as it enters the groove 81. This makes the fastening action smoother and reduces assembly resistance. Simultaneously, the anti-rebound slope 811 on the inner wall of the second snap fastener groove 81 effectively prevents the second snap fastener 84 from accidentally falling off, ensuring the fastening strength. Furthermore, due to the connecting action of the movable hinge, the first snap fastener 83, in conjunction with the second snap fastener 84, achieves a coupling of two connection methods—simultaneous locking at two points—which is more reliable than a single connection method.

[0055] The connector structure of this invention has extremely high scalability. In practical applications, the dimensions of the housing assembly 2 and the shielding ring 4 can be adjusted according to the cable current carrying capacity requirements, perfectly adapting to a full range of high-voltage cables with cross-sectional areas ranging from 25mm² for low-power to 150mm² for high-power DC fast charging. Furthermore, to adapt to different vehicle-mounted equipment interfaces, the external thread specifications of the metal mounting head 21 can cover various standard metric threads such as M16, M25, M32, and M36, and special threads can also be customized according to customer needs, all of which fall within the scope of protection of this invention.

Claims

1. An automotive-grade single-core through-hole shielded connector, characterized in that, The cable includes an O-ring (1), a housing assembly (2), a shielding ring (4), a sealing body (5), and a tail cap. The housing assembly (2) includes a metal mounting head (21) and a plastic housing (22) that is injection molded and covers the outside of the metal mounting head (21). The threaded end of the housing assembly (2) is provided with an annular groove. The O-ring (1) is installed in the annular groove. The shielding ring (4) is an integrally formed metal component that is fitted and fixed on the shielding layer of the cable (7) and placed inside the housing assembly (2). The sealing body (5) is installed on one side of the shielding ring (4) and abuts against the tail cap. The tail cap is fitted on the outside of the cable (7) and fixed by fastening with the housing assembly (2). The shielding ring (4) is a seamless cylindrical metal strip formed by multiple drawing processes. The structure consists of a crimping cylinder, a stress isolation groove (41), a positioning step, and an annular contact part arranged sequentially along the axial direction. The crimping cylinder is fixed to the shielding layer of the cable (7) by plastic deformation crimping. The stress isolation groove (41) is an annular necking structure arranged circumferentially to block the transmission of deformation stress of the crimping cylinder to the annular contact part. The positioning step extends radially outward to form an abutment surface, which cooperates with the blocking step on the inner wall of the metal mounting head (21) to form an axial stop. The annular contact part is provided with several C-shaped grooves (43), which surround and form an outwardly protruding elastic contact tongue. The elastic contact tongue has a spherical protrusion (42), which uses the elastic deformation ability of the root of the C-shaped groove to maintain interference contact with the inner wall of the metal mounting head (21).

2. The automotive-grade single-core through-hole shielded connector according to claim 1, characterized in that, The number of spherical convex humps (42) is 2 to 20, and they are evenly distributed along the circumference of the annular contact portion. The convex direction of the spherical convex humps (42) is radially outward.

3. The automotive-grade single-core through-hole shielded connector according to claim 1, characterized in that, The shielding ring (4) and the housing assembly (2) are sized to accommodate cables (7) with a cross-sectional area ranging from 25 mm² to 150 mm². The external thread specifications of the metal mounting head (21) include, but are not limited to, standard metric threads of M16, M25, M32 and M36.

4. The automotive-grade single-core through-hole shielded connector according to claim 1, characterized in that, The tail cover is tail cover A (6), which includes a tail cover body and a buckle structure; the buckle structure includes cantilever beams on both sides of the tail cover body and barbs at the ends of the cantilever beams, and the outer shell assembly (2) is provided with a groove that cooperates with the barbs.

5. The automotive-grade single-core through-hole shielded connector according to claim 1, characterized in that, The tail cap is tail cap B (8), which is used to connect the bellows (9). The outer wall of the tail cap B (8) is provided with a first snap-fit ​​groove (82) and a second snap-fit ​​groove (81). The outer wall of the first snap-fit ​​groove (82) is connected to a fastener by an integrally injection-molded movable hinge.

6. The automotive-grade single-core through-hole shielded connector according to claim 5, characterized in that, The fastener is provided with a first buckle (83) at one end near the first buckle groove (82), and the first buckle (83) engages with the first buckle groove (82); the fastener is provided with a second buckle (84) at one end away from the first buckle groove (82), and the second buckle (84) engages with the second buckle groove (81).

7. The automotive-grade single-core through-hole shielded connector according to claim 5, characterized in that, The inner wall of the tail cap B (8) is provided with a first limiting rib, and the inner wall of the fastener is provided with a second limiting rib. The first limiting rib and the second limiting rib (85) cooperate to clamp the trough position of the bellows (9).

8. The automotive-grade single-core through-hole shielded connector according to claim 1, characterized in that, It also includes a terminal (3) which is crimped to the conductor end of the cable (7) and passes through the shielding ring (4) and extends to the outside of the housing assembly (2).

9. The automotive-grade single-core through-hole shielded connector according to claim 1, characterized in that, The outer surface of the metal mounting head (21) is provided with an anti-rotation groove (211) and an axial limiting groove (212). The anti-rotation groove (211) and the axial limiting groove (212) are filled with the injection molding material of the plastic shell (22) to form an interlocking fixing structure.

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