Waterproof electrical plug structure

Abstract

The utility model discloses a waterproof electric butt joint plug structure, including the first joint and second joint all by insulating material are made. The first joint is provided with the insulator in, is equipped with the connecting post with arc welding portion on the insulator, and this arc welding portion has increased the welding contact area with the wire obviously. The cross -shaped partition block is equipped with on the insulator, and the connecting post is arranged around the partition block and keeps the interval of not less than 6mm, ensures electrical safety. The second joint front end is equipped with the plug, and the plug outer wall is covered with the sealing washer. The nut of second joint is covered and is connected with the first joint screw thread, and the sealing washer is formed radial seal by pressing. The utility model discloses through optimizing welding structure, insulation layout and sealing cooperation, effectively solved the small welding area of traditional plug, the connection is not firm, the problem of easy heating and poor waterproofness, realized the significant promotion of electric connection reliability, safety and durability.

Description

Technical Field

[0001] This utility model relates to the field of plug technology, and in particular to a waterproof electrical connection plug structure. Background Technology

[0002] Wire connectors, also known as wire ends, are critical components used in wire laying to connect different sections of wire into a continuous circuit. The reliability and stability of their connection directly affect the safety and performance of the entire circuit system.

[0003] Existing waterproof electrical connectors typically consist of a first connector with a conductive post and a second connector with a slot, achieving a conductive connection through insertion. The conductive post is commonly welded to external wires. However, the conductive post in such structures is usually a simple cylindrical or needle-shaped piece, with a limited surface area for welding. This design has significant drawbacks: First, the small welding area results in insufficient connection strength between the wire and the conductive post, making the weld prone to cracking and connection failure under external pulling or vibration. Second, the limited contact area increases contact resistance; according to Joule's law, when current flows, a large amount of heat is generated at the connection point, leading not only to energy loss but also a fire hazard due to overheating. Furthermore, weak welding can cause arcing, further accelerating connector aging.

[0004] For example, Chinese utility model patent (publication number: CN209822975U) discloses a waterproof electrical connector structure, which improves guidance and sealing. However, the connection between the conductive post and the wire still uses a traditional form, failing to solve the fundamental problems of weak connection and easy overheating caused by the small welding area. In-depth analysis reveals that while existing technologies such as the structure disclosed in patent CN209822975U improve guidance and external sealing, the conductive post in the core electrical connection part still uses a traditional columnar or needle-shaped design, limiting the surface area of ​​the welding point with the wire. This inherent defect leads to insufficient mechanical strength of the welding point, making it prone to fatigue fracture under vibration. Simultaneously, the small contact area results in high contact resistance. According to Joule's law: P = I²R, significant heat is generated when a large current passes through, leading to excessive temperature rise at the connector, posing a safety hazard and accelerating material aging.

[0005] Therefore, given the inherent defects of existing electrical plug structures, such as small welding area of ​​conductive posts and unreliable connection, there is an urgent need for a new structural design that can significantly increase the welding area, thereby achieving a more robust, stable, and electrically superior electrical connection. Summary of the Invention

[0006] The technical problem to be solved by this utility model is to provide an electrical connector structure that is reasonable in structure, has a firm connection, stable electrical performance and good waterproof performance, in order to address the defects of existing electrical connector structures such as small welding area of ​​conductive posts, unreliable connection, easy overheating and safety hazards.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A waterproof electrical connector structure includes a first connector and a second connector. The first connector contains an insulator with four connecting posts passing through it. Each connecting post has an arc-shaped welding end for welding to an external conductor, and the other end extends into the cavity of the first connector for electrical connection with the second connector. A partition block is also provided on the insulator, around which the four connecting posts are arranged to achieve electrical isolation. The second connector has a plug at its front end, which can be inserted into the cavity of the first connector and make contact with the connecting posts for electrical communication. A nut is fitted onto the second connector, and this nut is threadedly connected to the first connector, thereby fixing the second connector to the first connector and achieving a mechanical locking and sealing fit between the two.

[0008] Furthermore, the surface of the insulator is provided with recesses, which can be used to accommodate sealant or enhance the bonding strength between the insulator and the first joint.

[0009] Furthermore, the outer surface of the first connector is provided with external threads, and the nut is provided with internal threads, so that a reliable connection can be achieved through the cooperation of the internal and external threads.

[0010] Furthermore, the insulator is circular in shape, which facilitates processing and assembly.

[0011] Furthermore, the separator is cross-shaped, which helps to evenly separate the four connecting posts and enhances insulation safety.

[0012] Furthermore, the spacing between the four connecting posts is set to at least 6 mm to meet the safety requirements for electrical clearance and creepage distance.

[0013] Furthermore, the end of the plug is provided with a guide bevel, which facilitates insertion into the socket and improves the convenience and accuracy of docking.

[0014] Furthermore, a sealing ring is fitted on the outer wall of the plug of the second connector to achieve a waterproof seal after docking.

[0015] Furthermore, the insulator is made of flame-retardant engineering plastic, which improves the fire safety of the product.

[0016] Furthermore, the surface of the arc-shaped welded part is provided with a silver plating layer to reduce contact resistance and improve conductivity and oxidation resistance.

[0017] The beneficial effects of this utility model are as follows: 1. By setting an arc-shaped welding part, this structure significantly increases the welding area between the connecting post and the wire, which not only improves the welding strength and avoids cracking of the weld point due to vibration or external force, but also effectively reduces contact resistance, reduces heat generation during power-on, and improves the reliability and safety of the electrical connection. 2. The use of a partition block structure and a reasonable layout of the connecting posts, combined with sufficient spacing design, effectively prevents short circuits between electrodes and enhances insulation performance. 3. Through the threaded connection between the nut and the first connector, combined with the sealing ring design, a good mechanical locking and waterproof sealing effect is achieved, adapting to the needs of use in complex environments. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings.

[0019] Figure 1 This is a schematic diagram of the structure of this utility model.

[0020] Figure 2 for Figure 1 A top-view structural diagram.

[0021] Figure 3 for Figure 1 A schematic diagram of the main structure.

[0022] Figure 4 for Figure 1 A schematic diagram of the usage state structure.

[0023] Figure 5 This is a schematic diagram of the docking structure of this utility model.

[0024] Explanation of reference numerals in the attached drawings: Insulator 1, Recess 101, Connecting post 2, Arc-shaped welded part 201, Separator block 3, First connector 4, External thread 401, Insert cavity 402, Second connector 5, Plug 501, Sealing ring 502. Guide slope 503, nut 6, internal thread 601. Detailed Implementation

[0025] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0026] Example 1: See Figures 1 to 5This embodiment provides a typical waterproof electrical connector structure, the core of which is to comprehensively improve the reliability, safety and durability of the connection by increasing the welding area, optimizing the insulation layout and strengthening the sealing structure.

[0027] The structure and materials are as follows: Insulator 1, as the core insulating component, is integrally molded from flame-retardant engineering plastic (e.g., reinforced nylon PA66 with 30% glass fiber) using an injection molding process. This material possesses good mechanical strength, electrical insulation (insulation resistance > 1000MΩ), high-temperature resistance (heat distortion temperature ≥ 220℃), and a flame-retardant rating (reaching UL94 V-0). Insulator 1 is generally circular in shape, preferably with a diameter of 24mm and a thickness of 10mm, to provide sufficient creepage distance and clearance.

[0028] Connecting posts 2: There are four of them, precision-machined from T2 copper rods with excellent conductivity. Each connecting post 2 passes through a corresponding through hole on the insulator 1, with one end extending into the insertion cavity 402 of the first connector 4 as a plug-in terminal, and the other end having an arc-shaped welding part 201. The radius of curvature of the arc-shaped welding part 201 is R3mm, and the arc length is not less than 7mm, thereby increasing the effective welding area by approximately 50% to 80% compared to the traditional flat or cylindrical end. To further reduce contact resistance and enhance oxidation resistance, the entire connecting post 2, especially the surface of the arc-shaped welding part 201, is provided with a silver plating layer with a thickness of not less than 5μm.

[0029] The separator 3 is integrally formed with the insulator 1, and is cross-shaped, with a height of 6mm and a thickness of 2mm. Four connecting posts 2 are evenly arranged around the cross-shaped separator 3, forming four independent insertion channels. This design effectively increases the creepage distance between adjacent connecting posts 2, ensuring that the minimum distance between any two connecting posts 2 is not less than 6mm, meeting the safety standard requirements for higher voltage levels (such as AC 450V).

[0030] First connector 4: As the main body of the socket, it is also made of the aforementioned flame-retardant engineering plastic (such as PA66+30%GF). The first connector 4 has a cylindrical socket 402 inside to accommodate the plug 501 of the second connector 5. The outer surface of the first connector 4 is machined with a standard external thread 401, for example, M28×1.5, with a thread length of 15mm, for connection with the nut 6.

[0031] The second connector 5: Its front end plug 501 is designed as a cylinder to mate with the socket 402, with an outer diameter slightly smaller than the inner diameter of the socket 402, forming a guide gap. The end of the plug 501 is machined with a guide bevel 503, preferably at an angle of 30° to 45°, to ensure smooth insertion and accurate alignment. A sealing ring 502 is fitted in the groove at the root of the plug 501. This sealing ring is preferably made of a weather-resistant and elastic silicone rubber (such as VMQ), with a Shore A hardness between 50 and 60 degrees and a cross-sectional diameter of 2.0 mm.

[0032] Nut 6: Made of high-strength nylon or metal, its inner wall is machined with an internal thread 601 that matches the external thread 401 of the first connector 4. The function of nut 6 is to lock and fix the second connector 5 to the first connector 4 through threaded connection, and to compress the sealing ring 502 to achieve radial sealing.

[0033] The assembly process of this utility model has a clear logic, which facilitates automated production. Pre-assembled insulation module: Press the four connecting posts 2 into the corresponding through holes from the rear end of the insulator 1, ensuring that the plug terminals at the front end of the connecting posts 2 extend into the plug cavity 402 by about 4mm, and the arc-shaped welding part 201 at the rear end protrudes from the rear end face of the insulator 1 by about 3mm.

[0034] Integrating the first connector: The pre-assembled assembly of insulator 1 and connecting post 2 is pressed into the housing of the first connector 4 using a special jig until it is fully locked in place. At this time, the recess 101 on the surface of insulator 1 can interlock with the protruding structure on the inner wall of the first connector 4, or it can be used to apply a small amount of structural adhesive to further enhance the bonding force and sealing performance.

[0035] Prepare the second connector: Accurately insert the sealing ring 502 into the plug 501 of the second connector 5. Then, put the nut 6 onto the second connector 5.

[0036] Final connection: Align the plug 501 of the second connector 5 with the socket 402 of the first connector 4, and easily insert it using the guide ramp 503. Then tighten the nut 6, controlling the tightening torque within the range of 1 N·m to 2 N·m. This process causes the sealing ring 502 to be uniformly compressed, producing radial deformation, and tightly filling the space between the outer wall of the plug 501 and the inner wall of the socket 402, forming a reliable waterproof sealing interface.

[0037] After stripping 8-10 mm of insulation from the external conductor (e.g., with a cross-sectional area of ​​2.5 mm²), it is welded to the arc-shaped welding part 201 of the connecting post 2 using a silver-containing solder (e.g., Sn96.5Ag3.0Cu0.5). Because the arc-shaped structure provides a larger heat capacity and welding area, the welding operation is more convenient, resulting in full, strong welds and significantly improved mechanical pull-out force.

[0038] To verify the effectiveness of this invention, the following tests were conducted: Waterproof performance: Tested according to IEC 60529 standard with IP67 rating. The connected plug is immersed in water to a depth of 1 meter for 30 minutes. After removal, there is no water residue inside, and the insulation resistance value (500VDC) remains above 1000MΩ.

[0039] Electrical performance: Under conditions of rated current of 16A and ambient temperature of 25℃, after continuous operation for 2 hours, the maximum temperature rise of the connector shell, measured using a thermal imager, does not exceed 22K. Using a micro-ohmmeter, the contact resistance of a single connection point remains stable below 0.3mΩ.

[0040] Mechanical reliability: Pull-out tests on the weld joints showed an average destructive force exceeding 150N, far higher than traditional structures (typically below 90N). After vibration testing (frequency 10-55Hz, amplitude 0.75mm, duration 2 hours), the change rate of connection resistance was less than 2%, with no signs of loosening.

[0041] Comparative test: Under the same test conditions, compared with the plug of the traditional cylindrical welded part, the temperature rise of the plug of this utility model is reduced by 15 to 20K under rated current, and the pull-out force of the weld point is increased by about 70%.

[0042] Example 2 is as follows: Based on Example 1, to adapt to more severe industrial environments (such as chemical corrosion or higher intensity mechanical vibration), the following optimizations can be made: The first connector 4 and the insulator 1 can be made of polyphenylene sulfide (PPS), which has better performance, chemical corrosion resistance, and long-term thermal stability.

[0043] The material of the sealing ring 502 can be replaced with fluororubber FKM to provide a wider temperature range (-20°C to 200°C) and better oil and chemical resistance. Tested to have a volume change of less than 5% after immersion in ASTM IRM 903 oil for 70 hours, it maintains good sealing performance.

[0044] Special waterproof and shockproof sealant (such as polyurethane sealant) can be injected into the recess 101 of the insulator 1 and the junction of the first connector 4 and the cable outlet to form multiple sealing protections and further improve the protection level of the overall structure to IP68 or above.

[0045] In summary, through the specific and feasible implementation methods described above, this utility model effectively solves the technical problems mentioned in the background art, such as small welding area, unreliable connection, and easy overheating, while providing excellent waterproof performance, and has significant technological progress and industrial application value.

Claims

1. A waterproof electrical connector structure, comprising a first connector (4) and a second connector (5), characterized in that: An insulator (1) is provided inside the first connector (4). Four connecting posts (2) are provided on the insulator (1). The four connecting posts (2) pass through the insulator (1). One end of each connecting post (2) is provided with an arc-shaped welding part (201), and the other end extends into the insertion cavity (402) of the first connector (4). The insulator (1) is provided with a partition block (3), and the four connecting posts (2) are arranged around the partition block (3); The front end of the second connector (5) is provided with a plug (501), which is configured to be inserted into the cavity (402) of the first connector (4) and electrically connected to the connecting post (2); The second connector (5) is fitted with a nut (6), which is threadedly connected to the first connector (4) to fix the second connector (5) to the first connector (4).

2. The waterproof electrical connector structure according to claim 1, characterized in that: The surface of the insulator (1) is provided with a recess (101).

3. The waterproof electrical connector structure according to claim 1, characterized in that: The outer surface of the first connector (4) is provided with an external thread (401), and the nut (6) is provided with an internal thread (601). The external thread (401) and the internal thread cooperate to achieve a threaded connection.

4. The waterproof electrical connector structure according to claim 1, characterized in that: The insulator (1) is circular in shape.

5. The waterproof electrical connector structure according to claim 1, characterized in that: The dividing block (3) is cross-shaped.

6. The waterproof electrical connector structure according to claim 1, characterized in that: The spacing between the four connecting posts (2) is at least 6 mm.

7. The waterproof electrical connector structure according to claim 1, characterized in that: The end of the plug (501) is provided with a guide bevel (503).

8. The waterproof electrical connector structure according to claim 1, characterized in that: The plug (501) of the second connector (5) is fitted with a sealing ring (502) on its outer wall.

9. The waterproof electrical connector structure according to claim 1, characterized in that: The insulator (1) is made of flame-retardant engineering plastic.

10. The waterproof electrical connector structure according to claim 1, characterized in that: The surface of the arc-shaped welded part (201) is provided with a silver plating layer.

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