Cylindrical terminals, plug-in connector structures, and machining methods for cylindrical terminals.

Abstract

The invention relates to a cylindrical end, a plug-in connection structure, and a method for machining a cylindrical end. The cylindrical end comprises a contact section (10), a fixed section (20), and a connecting section (30). The fixed section (20) comprises an extension section (201) and an assembly section (202) injection molded onto the extension section (201). The contact section (10), the extension section (201), and the connecting section (30) are made in one piece in the form of a cylindrical tube. The contact section (10) has at least two axial slots (102), such that the side wall of the contact section (10) is divided into at least two contact elastic plates (103). The extension section (201) has a radially concave section, such that the contact elastic plates form arc-shaped structures. The plug-in connection structure comprises a plug (40) and a cylindrical end. A method for machining a cylindrical end is also described.

Description

A barrel-type terminal, plug-in connection structure and processing method thereof

[0001] Related applications

[0002] This application claims priority to the Chinese invention patent application with application number 202110803204.9 filed on July 15, 2021, and the Chinese utility model patent application with application number 202121613435.5 filed on July 15, 2021, and cites the contents disclosed in the above patent applications as part of this application. Technical Field

[0003] The present application relates to the field of electrical connections, and in particular to a barrel terminal, a plug-in connection structure, and a processing method thereof. Background Art

[0004] In the field of electrical connections, many electrical circuits require connectors. Currently, most connectors use male and female terminals for connection, especially in high-current, large-diameter wiring harnesses. For example, in the rapidly developing new energy vehicles, the charging guns and charging stations for charging batteries all have internal terminals that are male and female. Due to the high current carrying capacity, the cross-sectional area of ​​the connectors is also large. Currently, commonly used connectors are all turned from copper rods, which has low material utilization, complex processing, and long processing time. Especially in the processing of the female terminals, more copper is wasted, which prevents the cost of the charging system from being reduced.

[0005] In addition, in order to assemble and seal the terminals on the electrical devices, an assembly area and a sealing area need to be set up outside the electrical functional area of ​​the terminals, which also requires a complex processing process and will result in the loss of some raw materials, making the material utilization rate even lower.

[0006] Therefore, a new solution is urgently needed in the prior art to solve the above problems.

[0007] Summary of the Invention

[0008] The present application provides a barrel-type terminal, a plug-in connection structure and a processing method thereof, which improves the utilization rate of terminal processing materials, has a simple processing technology, is time-saving, and greatly reduces the production cost of the terminal.

[0009] The technical solutions provided in this application are:

[0010] The embodiment of the first aspect of the present application provides a barrel terminal, comprising: a contact section, a fixing section, and a connecting section.

[0011] wherein the fixing section comprises an extension section and an assembly portion provided on the extension section;

[0012] The contact section, the extension section and the connection section are integrally formed into a cylindrical tube;

[0013] At least two axial slots are provided on the contact segment, so that the side wall of the contact segment is divided into at least two contact springs;

[0014] The contact section is recessed radially inward, so that the contact spring forms an arc-shaped structure;

[0015] The connecting section is electrically connected to the conducting wire.

[0016] An embodiment of the second aspect of the present application provides a plug-in connection structure, which includes a plug-in terminal and the barrel terminal described in the embodiment of the first aspect, the plug-in terminal is inserted into the contact section, and the outer side wall of the plug-in terminal is tightly fitted with the inner side wall of the contact spring.

[0017] The embodiment of the third aspect of the present application provides a processing method for manufacturing the barrel terminal of the embodiment of the first aspect, comprising:

[0018] S10, preparing a cylindrical tube;

[0019] S20, preparing an extruder and a mold, wherein the mold is divided into an inner mold and an outer mold, wherein the inner mold is provided with an arc-shaped depression and a first groove, and the outer mold is provided with an arc-shaped protrusion and a shearing table;

[0020] S30, placing the inner mold in the cylindrical tube, and then placing them together in the outer mold;

[0021] S40, starting the extruder, moving the arc-shaped protrusion of the outer die toward the arc-shaped depression of the inner die, and squeezing the contact section of the cylindrical tube into an inward depression;

[0022] S50, the extruder drives the shearing table of the outer die to continue to move, and cooperates with the first groove of the inner die to extrude the contact section of the cylindrical tube into an axial groove;

[0023] S60: The extruder drives the outer die to return to its original position, takes out the extruded cylindrical tube and the inner die from the outer die, and then takes out the inner die.

[0024] This application can bring the following beneficial effects:

[0025] 1. The barrel terminal of the present application is processed by a barrel tube and does not use rod-shaped materials, which can greatly improve material utilization.

[0026] 2. The barrel terminal of the present application uses an extruder or a rolling machine to process the depression and groove on the contact section and the opening of the extension section at one time, without the need for complex mechanical processing and reducing processing time.

[0027] 3. The barrel terminal of the present application has the assembly portion directly injection-molded on the barrel tube, eliminating the need for processing on the barrel tube material, thereby reducing material waste and enabling processing of complex assembly shapes.

[0028] 4. The barrel terminal of the present application can be provided with a first groove in the assembly part to assemble a sealing ring, or the sealing ring can be directly injection-molded in the assembly part, thereby reducing the complexity of the processing technology and reducing the processing time.

[0029] 5. This application provides an elastic contact spring so that the contact section can adapt to the processing error of the plug-end terminal, thereby increasing the bonding force between the barrel terminal and the plug-end terminal, ensuring a larger contact area, and achieving better electrical and mechanical properties.

[0030] 6. The cross-sectional shape of the inner hole of the contact section of the barrel terminal of the present application is designed into various shapes, which facilitates designers to select barrel terminals of different shapes according to the actual barrel terminal arrangement environment, reduce the volume of the plug-in structure, optimize the contact area, and enhance the electrical performance of the barrel terminal;

[0031] 7. The barrel terminal of the present application can be provided with an elastic kit. When the barrel terminal itself is not elastic enough due to design reasons, the elastic kit can be used to supplement the clamping force between the barrel terminal and the plug terminal;

[0032] 8. The barrel terminal of the present application adopts tellurium copper alloy, which makes the terminal have good conductivity and easy processing performance, ensuring electrical performance and improving processing performance. At the same time, the tellurium copper alloy also has excellent elasticity;

[0033] 9. The barrel terminal of the present application adopts a coating, which can better improve the corrosion resistance. Preferably, a composite coating is adopted, which can better improve the firmness of the coating and ensure that the coating does not fall off and is corrosion-resistant after multiple plugging and unplugging. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIG1 is a cross-sectional view of the barrel terminal described in this application;

[0035] FIG2 is a cross-sectional view of the extended section processing opening described in the present application;

[0036] FIG3 is a cross-sectional view of another example of the barrel terminal described in the present application;

[0037] FIG4 is a cross-sectional view of another example of the barrel terminal described in the present application;

[0038] FIG5 is a schematic structural diagram of a plug-and-socket connection structure of the present application;

[0039] FIG6 is a structural diagram of another plug-in connection structure of the present application;

[0040] FIG7 is a schematic flow chart of a first embodiment of a method for processing a barrel terminal according to the present application;

[0041] FIG8 is a schematic flow chart of a second embodiment of a method for processing a barrel terminal according to the present application;

[0042] FIG9 is a schematic flow chart of a third embodiment of a method for processing a barrel terminal according to the present application;

[0043] FIG10 is a schematic flow chart of a fourth embodiment of a method for processing a barrel terminal according to the present application;

[0044] FIG11 is a schematic flow chart of a fifth embodiment of a method for processing a barrel terminal according to the present application;

[0045] FIG12 is a schematic flow chart of a sixth embodiment of a method for processing a barrel terminal according to the present application;

[0046] 13 is a schematic flow chart of a seventh embodiment of a method for processing a barrel terminal according to the present application;

[0047] 14 is a schematic flow chart of an eighth embodiment of a method for processing a barrel terminal according to the present application;

[0048] FIG15 is a schematic flow chart of a ninth embodiment of a method for processing a barrel terminal according to the present application;

[0049] 16 is a schematic flow chart of a tenth embodiment of a method for processing a barrel terminal according to the present application;

[0050] 17 is a schematic flow chart of a fifteenth embodiment of a method for processing a barrel terminal according to the present application;

[0051] FIG. 18 is a flow chart of a sixteenth embodiment of a method for processing a barrel terminal according to the present application. DETAILED DESCRIPTION

[0052] The present application is described in further detail below so that those skilled in the art can implement it with reference to the text of the specification. In order to have a clearer understanding of the technical features, purposes and effects of the present application, the specific implementation methods of the present application are now described with reference to the accompanying drawings. Among them, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "multiple" means two or more. In the description of the present application, unless otherwise specified, the term "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, a direct connection, or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this patent can be understood according to the specific circumstances.

[0053] Implementation Method 1

[0054] The present application provides a barrel-type terminal, as shown in Figure 1 , comprising: a contact section 10, a fixed section 20, and a connecting section 30. The fixed section 20 includes an extension section 201 and an assembly portion 202 disposed on the extension section 201. The contact section 10, the extension section 201, and the connecting section 30 are integrally formed as a cylindrical tube. At least two axial slots 102 are provided in the contact section 10, dividing the sidewall of the contact section 10 into at least two contact springs 103. A radially inward recess 101 is provided in the contact section 10, forming an arc-shaped structure for the contact springs 103. The connecting section 30 is electrically connected to the conductor.

[0055] The barrel-type terminal of the present application is provided with a contact section 10. The interior of the contact section 10 is a cavity open on at least one side, which is used for plugging and connecting with the plug-end terminal 40 to achieve electrical conduction. At least two axial slots 102 are provided on the contact section 10, so that the side wall of the contact section 10 is divided into at least two contact springs 103. This allows the contact section 10 to adapt to the processing errors of the plug-end terminal 40. The contact springs 103 can respectively make contact-type connections with the plug-end terminal 40, thereby increasing the contact area between the contact section 10 and the plug-end terminal 40, reducing contact resistance, and avoiding poor contact between the contact section 10 and the plug-end terminal 40 due to uneven or irregular surfaces of the plug-end terminal 40, which may cause excessive heating of the terminal plug-end structure and lead to combustion accidents. The contact section 10 is provided with a recess 101 radially inwardly, so that the contact spring 103 forms an arc structure, and the contact spring 103 has an elastic force toward the inside, so that the contact section 10 and the plug-in terminal 40 have a greater bonding force. The arc structure of the contact spring 103 deforms along with the surface of the plug-in terminal 40, ensuring a larger contact area and achieving better electrical and mechanical properties, thereby solving the problem that the existing barrel terminal cannot meet the mechanical performance requirements and temperature rise requirements.

[0056] The barrel terminal of the present application is provided with a fixed section 20, which includes an extension section 201 and an assembly portion 202 provided on the extension section 201. One end of the extension section 201 is connected to the contact section 10, and the other end is connected to the connection section 30, and is electrically connected to both the contact section 10 and the connection section 30. The assembly portion 202 can be extruded or roll-formed from the extension section 201, or a plastic material can be directly injection-molded onto the extension section 201 using an injection molding machine. The assembly portion 202 is fixedly connected to the extension section 201 and is assembled and fixed to the installation position of the electrical device, so that the barrel terminal can be fixed to the corresponding position of the electrical device, facilitating connection with the plug terminal 40.

[0057] The barrel terminal of the present application is provided with a connecting section 30, which is electrically connected to the wire to realize the transmission of electric energy and signals. The cross-sectional shape of the connecting section 30 is circular, elliptical, open ring, U-shaped, flat, or polygonal. Different cross-sectional shapes can be selected according to the cross-sectional shape of the matching wire or the corresponding connection method. The connection between the connecting section 30 and the wire can be connected by crimping or welding. Crimping is a mechanical deformation method that applies pressure to deform the connecting section 30 and part of the wire inside it. The wire and the inside of the connecting section 30 are in full contact and connected together by friction. Welding methods include ultrasonic welding, resistance welding, arc welding, pressure welding, electromagnetic welding, laser welding and other welding methods, which weld the connecting section 30 and part of the wire together to achieve stable electrical and mechanical properties.

[0058] Ultrasonic welding uses high-frequency vibration waves to transmit to the surfaces of two objects to be welded. Under pressure, the two surfaces of the objects rub against each other to form a fusion between the molecular layers.

[0059] Resistance welding refers to a method of welding that uses a strong current to pass through the contact point between the electrode and the workpiece, generating heat due to the contact resistance.

[0060] Arc welding refers to the use of electric arc as a heat source and the physical phenomenon of air discharge to convert electrical energy into the thermal energy and mechanical energy required for welding, thereby achieving the purpose of connecting metals. The main methods include arc welding, submerged arc welding, gas shielded welding, etc.

[0061] Pressure welding is a method of applying pressure to the weldment to bring the joint surfaces into close contact and produce a certain amount of plastic deformation to complete the welding.

[0062] Electromagnetic welding uses an electromagnetic induction coil to generate a short and very strong current from a pulse generator. The electromagnetic field generated by the induction coil can instantly collide and squeeze the materials to be welded together.

[0063] Laser welding is an efficient and precise welding method that uses a high-energy-density laser beam as a heat source.

[0064] The barrel-type terminal of the present application, as shown in FIG1 , has a slot 102 on the contact section 10 extending through the side of the contact section 10 away from the fixed section 20, and a contact spring 103 having a free end. Such a contact spring 103 can accommodate machining errors of the plug-in terminal 40. Multiple contact springs 103 can be individually connected to the plug-in terminal 40 in a contact-type manner, thereby increasing the contact area between the contact section 10 and the plug-in terminal 40 and reducing contact resistance. This prevents poor contact between the contact section 10 and the plug-in terminal 40 due to uneven or irregular surfaces of the plug-in terminal 40, which could result in excessive heating of the terminal plug-in structure and lead to combustion accidents. Since the contact spring 103 has a free end, the contact force with the plug-in terminal 40 is ensured by the elasticity of the material of the contact spring 103 itself. The elastic force is relatively small and the spring is not easily self-recovering after deformation. Therefore, the contact spring 103 is suitable for applications where the conduction current is small, the tolerance of the plug-in terminal 40 is large, and the relative movement after plugging is small.

[0065] In the barrel-type terminal of the present application, the width of the slot 102 on the contact section 10 on the side close to the fixed section 20 is greater than or equal to the width on the side away from the fixed section 20. The slot 102 on the contact section 10 on the side away from the fixed section 20 is generally the position where the contact spring 103 and the plug-in terminal 40 contact each other. In order to obtain a larger contact area, the smaller the width of the slot 102 on the contact section 10 on the side away from the fixed section 20, the better. In addition, since water and sediment will enter the cavity of the contact section 10 during use, in order to make the plug-in structure perform better and extend its service life, a position for draining sediment and water should be designed on the barrel-type terminal. Therefore, the larger the width of the slot 102 on the contact section 10 on the side close to the fixed section 20, the better the drainage and drainage performance.

[0066] In the embodiment where the shape of the fixed section of the barrel terminal of the present application is not too complicated, the assembly portion 202 can be directly extruded or rolled out on the extension section 201 without adding other processing methods or providing other components. The processing is simple and can be processed together with the groove and recess 101, saving processing time and improving production efficiency.

[0067] The assembly portion 202 of the barrel terminal of this application can be processed and formed by injection molding when the shape of the fixed section is complex or requires additional components for assembly. Generally, the assembly portion 202 is made of plastic. Injection molding is a mature process with minimal processing time. Furthermore, the plastic material is relatively strong, enabling the barrel terminal to be securely fixed to the electrical device.

[0068] The barrel terminal of the present application, as shown in FIG2 , is provided with an opening 206 on the extension section 201, which enables the assembly portion 202 formed by injection molding to be integrated inside and outside the barrel tube. The assembly portion 202 is assembled and fixed to the installation position of the electrical device, so that the barrel terminal can be fixed to the corresponding position of the electrical device, conveniently connecting with the plug-in terminal 40. If the assembly portion 202 is not firmly fixed to the extension section 201, the barrel terminal will move inside the electrical device, resulting in unstable contact between the barrel terminal and the plug-in terminal 40, and the plug-in structure cannot achieve good mechanical and electrical properties. The opening is provided on the extension section 201, so that when the assembly portion 202 is injection molded, the molten assembly portion 202 material can enter the barrel tube from the outside along the opening into the barrel tube, so that the assembly portion 202 and the extension section 201 can be firmly connected together, ensuring that the assembly portion 202 and the extension section 201 will not separate during use, thereby ensuring the stability of the plug-in structure.

[0069] In the barrel terminal of the present application, the barrel tube is a seamless tube or a seamed tube made from rolled sheet metal. In the manufacture of the barrel terminal of the present application, since the clamping force is mainly provided by the elasticity of the contact spring 103, the sealing of the barrel tube is not required to be high. Therefore, the barrel tube can be a seamless tube or a seamed tube.

[0070] When the cylindrical tube is a seamed tube, the width of the seam of the cylindrical tube cannot be greater than the width of the slot 102 on the contact section 10. In addition, during the processing, no seam can exist on the contact spring 103. The slot 102 on the contact section 10 is set on the seam of the cylindrical tube, which can ensure the elasticity of the contact spring 103 and make the cylindrical terminal and the mating terminal 40 more stable after insertion.

[0071] In the barrel terminal of the present application, the inscribed cross-section of the inner surface of the arc-shaped structure of the contact section 10 is circular, elliptical, polygonal, flat, E-shaped, F-shaped, H-shaped, K-shaped, L-shaped, T-shaped, U-shaped, V-shaped, W-shaped, X-shaped, Y-shaped, Z-shaped, semi-arc-shaped, arc-shaped, or wavy. The inscribed cross-section of the inner surface of the arc-shaped structure of the contact section 10 is designed to have various shapes, making it convenient for designers to select barrel terminals of different shapes based on the actual barrel terminal layout environment, reducing the volume of the plug-in structure, optimizing the contact area, and enhancing the electrical performance of the barrel terminal. In addition, the barrel terminal has a variety of inscribed cross-section shapes, which can match a variety of shapes of plug-in terminals 40, providing designers with more options.

[0072] In the barrel terminal of this application, the inner surface of the arcuate structure of the contact section 10 is at a uniform distance from the barrel terminal axis. When the cross-sectional area of ​​the plug-in position of the plug-in terminal 40 is circular, the contact spring 103 and the plug-in terminal 40 are at a uniform contact distance, ensuring that the clamping force of the contact spring 103 and the plug-in terminal 40 is substantially consistent, thus achieving stable electrical and mechanical properties for the plug-in structure and a longer service life.

[0073] In some embodiments, the end of the contact segment away from the fixed segment is provided with an outwardly flared chamfer, with the chamfer angle ranging from 17° to 178°. The expanded opening of the front segment facilitates the guidance of the plug terminal 40 for insertion. The inventors conducted repeated tests at different angles and found that when the chamfer angle was less than 17°, it was difficult for the plug terminal 40 to be directly inserted into the contact segment 10, requiring multiple insertions to complete the connection. Similarly, when the chamfer angle was greater than 178°, the plug terminal 40 was easily pressed against the inner side of the chamfer during insertion, also requiring multiple insertions to complete the connection.

[0074] The inventors selected 10 plug-in terminals of the same diameter and the same expansion and contraction gap width for testing, set different chamfer angles for each terminal, and matched them with the same plug-in terminal 40. The test was carried out 10,000 times of plugging and unplugging, and the number of times the terminals failed to be properly plugged in was observed and recorded. The test results are shown in Table 1.

[0075] In this embodiment, the ideal value for the number of times the insertion fails is less than 5.

[0076] Table 1: Effect of different chamfer angles on the number of misalignments in plug-in connection structures

[0077]

[0078] As can be seen from Table 1, when the chamfer angle on the contact segment is less than 17° and greater than 178°, the number of times the plug-end terminal 40 is not properly inserted into the plug terminal exceeds the ideal value, which cannot ensure the working stability of the plug-in connection structure. In addition, the misalignment will damage the terminal, greatly reducing the service life of the plug-in connection structure. In severe cases, it can cause damage to the terminal, the temperature rise of the plug-in connection structure is too high, causing the electrical device to burn, and causing accidents such as electric shock and casualties. Therefore, the inventors set the angle range of the chamfer of the contact segment to 17° to 178°.

[0079] The barrel terminals of this application can be made of copper or a copper alloy, which offers excellent electrical conductivity and elasticity. However, with rising copper prices, the cost of using copper for barrel terminals will continue to rise. Aluminum accounts for approximately 7.73% of the Earth's crust. With optimized extraction technology, its price is relatively low. Furthermore, aluminum is lighter than copper and has a conductivity second only to copper, making it a suitable alternative for copper in electrical connections. Therefore, aluminum or an aluminum alloy, which offers good electrical conductivity but moderate elasticity, but is less expensive, can also be chosen.

[0080] When copper alloy is selected as the material of the barrel terminal, preferably, the copper material contains tellurium material, so that the terminal has good conductivity and easy cutting performance, ensuring electrical performance and improving processability. At the same time, the tellurium copper alloy also has excellent elasticity.

[0081] Preferably, the tellurium content in the tellurium-copper alloy is 0.1%-5%. More preferably, the tellurium content in the tellurium-copper alloy is 0.2%-1.2%.

[0082] The inventors tested 10 plug-in terminals of identical shape and expansion joint width. Each terminal was made of a tellurium-copper alloy with tellurium contents of 0.05%, 0.1%, 0.2%, 1%, 1.2%, 1.8%, 3%, 5%, 6%, and 7%, respectively. The test results are shown in Table 2.

[0083] Table 2: Effect of different tellurium contents on electrical conductivity of tellurium-copper alloys

[0084] Tellurium content 0.05% 0.1% 0.2% 1% 1.2% 1.8% 3% 5% 6% 7% Electrical conductivity 93.8% 95.2% 97.5% 97.1% 98.3% 96.8% 96.6% 94.8% 93.9% 92%

[0085] As shown in Table 2, when the tellurium content is less than 0.1% or greater than 5%, the conductivity decreases significantly, failing to meet practical requirements. When the tellurium content is greater than or equal to 0.2% and less than or equal to 1.2%, the conductivity is optimal. Therefore, the inventors selected a tellurium-copper alloy with a tellurium content of 0.1%-5%. In the most ideal case, a tellurium-copper alloy with a content of 0.2%-1.2% is selected.

[0086] The electrical device where the barrel terminal of the present application is located often works outdoors, and it is inevitable that water will enter the electrical device. In order to ensure the safety of the electrical connection and the service life of the electrical device, a sealing structure needs to be provided on the barrel terminal. Since the barrel terminal is assembled with the electrical device through the assembly part 202, it is necessary to provide a first groove 203 on the periphery of the assembly part 202, and assemble a sealing ring in the first groove 203. The sealing ring cooperates with the interior of the electrical device to effectively seal the electrical device and ensure that external water does not enter the interior of the electrical device. The sealing ring is made of rubber material and has good elasticity. It can be squeezed and deformed after the barrel terminal is assembled with the electrical device to form a sealing structure to prevent water from entering the electrical device. In addition, the rubber material has good water resistance and oil resistance, which can extend the service life of the sealing structure.

[0087] The barrel terminal of the present application, as shown in Figures 1 and 3, has a second groove 104 arranged along the circumferential direction on the outer side of the contact section 10. The second groove 104 is an annular groove. At least one elastic sleeve 105 is sleeved on the second groove 104 to tighten the contact section 10 so that the contact spring 103 and the plug-in terminal 40 have better fit. It should be noted that when the barrel terminal is designed to be too thin due to the use environment, or the number of openings is large, or the diameter difference with the plug-in terminal 40 is large, the gripping force of the contact spring 103 and the plug-in terminal 40 will be insufficient, resulting in a reduction in the contact area between the barrel terminal and the plug-in terminal 40 and deterioration of the electrical performance. When the barrel terminal itself lacks elasticity due to design reasons, the elastic sleeve 105 can be used to supplement the gripping force between the barrel terminal and the plug-in terminal 40. The elastic sleeve 105 can be an elastic rubber body or an open elastic rigid body, which can limit the contact spring 103 of the barrel terminal from further expanding outward, thereby increasing the gripping force between the contact spring 103 and the plug terminal 40 .

[0088] The barrel terminal of the present application is provided with a coating at least partially on the contact section 10 and / or the connection end 30 in order to improve corrosion resistance, improve conductivity, increase the number of plug-in times, and better extend the service life of the contact section 10 and the connection end 30.

[0089] The coating can be formed by electroplating, chemical plating, magnetron sputtering or vacuum plating.

[0090] Electroplating is the process of plating a thin layer of other metals or alloys on certain metal surfaces using the principle of electrolysis.

[0091] The chemical plating method is a metal deposition process that produces metal through a controllable redox reaction under the catalytic action of the metal.

[0092] Magnetron sputtering utilizes the interaction of magnetic and electric fields to cause electrons to spiral near the target surface, thereby increasing the probability of electrons striking argon gas to generate ions. These ions, under the influence of the electric field, collide with the target surface, sputtering the target material.

[0093] The vacuum plating method is to deposit various metal and non-metallic films on the surface of parts through distillation or sputtering under vacuum conditions.

[0094] The plating material is one or more combinations of gold, silver, nickel, tin, tin-lead alloy, zinc, silver-antimony alloy, palladium, palladium-nickel alloy, graphite silver, graphene silver and silver-gold-zirconium alloy. Copper or aluminum, as an active metal, will undergo oxidation reactions with oxygen and water during use. Therefore, one or more inactive metals are required as plating to extend the service life of the barrel terminal. In addition, for metal contacts that need to be frequently plugged in and out, better wear-resistant metals are also required as plating, which can greatly increase the service life of the contacts. In addition, the contacts need to have good electrical conductivity. The conductivity and stability of the above metals are better than copper or copper alloys, aluminum or aluminum alloys, which can enable the barrel terminal to obtain better electrical performance and longer service life.

[0095] To demonstrate the impact of different plating materials on the overall performance of barrel terminals, the inventors used barrel terminal samples of the same specifications and material, but with different plating materials, and conducted a series of plug-in and plug-out cycle and corrosion resistance tests using the same specifications of the plug-in terminal 40. The experimental results are shown in Table 3 below.

[0096] The plugging and unplugging times reported in Table 3 below are calculated by attaching a barrel terminal and a mating terminal 40 to a test bench. A mechanical device is used to simulate plugging and unplugging the barrel terminal and mating terminal 40. After every 100 plugging and unplugging cycles, the test is stopped to observe damage to the barrel terminal's surface plating. If scratches appear on the barrel terminal's surface plating, exposing the barrel terminal's material, the test is terminated and the plugging and unplugging times recorded. In this embodiment, plugging and unplugging times less than 8,000 cycles are considered unacceptable.

[0097] The corrosion resistance time test in Table 3 below involves placing the barrel terminal in a salt spray test chamber. Salt spray is applied to various locations on the barrel terminal. The barrel terminal is removed, cleaned, and observed for surface corrosion every 20 hours. This constitutes one cycle. Testing is stopped until the surface corrosion area of ​​the barrel terminal exceeds 10% of the total area. The cycle count is then recorded. In this example, cycles less than 80 are considered unsatisfactory.

[0098] Table 3: Effects of different plating materials on the plug-in and pull-out cycles and corrosion resistance of barrel terminals

[0099]

[0100] As can be seen from Table 3 above, when the coating materials are gold, silver, silver-antimony alloy, palladium, palladium-nickel alloy, graphite silver, graphene silver, and silver-gold-zirconium alloy, the experimental results significantly exceed the standard values, and the performance is relatively stable. When the coating materials are nickel, tin, tin-lead alloy, and zinc, the experimental results also meet the requirements. Therefore, the inventors selected the coating materials as one or more combinations of gold, silver, nickel, tin, tin-lead alloy, zinc, silver-antimony alloy, palladium, palladium-nickel alloy, graphite silver, graphene silver, and silver-gold-zirconium alloy.

[0101] The coating includes a base layer and a surface layer.

[0102] In some embodiments, the coating is coated using a multi-layer coating method. After the contact segment 10 and the connecting end 30 are processed, there are still many gaps and holes under the surface microscopic interface. These gaps and holes are the biggest cause of wear and corrosion of the contact segment 10 and the connecting end 30 during use. Therefore, it is necessary to first coat a base layer on the surface of the contact segment 10 and the connecting end 30 to fill the gaps and holes on the surface, so that the surface of the contact segment 10 and the connecting end 30 is smooth and free of holes, and then coat the surface layer. The bonding will be stronger and smoother, and the coating surface will be free of gaps and holes, so that the wear resistance, corrosion resistance, and electrical performance of the barrel terminal are better, and the service life of the barrel terminal is greatly extended.

[0103] The bottom layer material of the coating is one or more combinations of gold, silver, nickel, tin, tin-lead alloy and zinc; the surface layer material of the coating is one or more combinations of gold, silver, nickel, tin, tin-lead alloy, zinc, silver-antimony alloy, palladium, palladium-nickel alloy, graphite silver, graphene silver and silver-gold-zirconium alloy.

[0104] In another embodiment, the bottom layer has a thickness of 0.01 μm to 15 μm. Preferably, the bottom layer has a thickness of 0.1 μm to 9 μm.

[0105] In another embodiment, the thickness of the surface layer is 0.5 μm-55 μm. Preferably, the thickness of the surface layer is 1 μm-35 μm.

[0106] To demonstrate the effect of variations in bottom plating thickness on the overall performance of barrel terminals, the inventors conducted a series of temperature rise and corrosion resistance time tests using barrel terminal samples of the same specifications and material, but with different nickel-plated bottom layer thicknesses and the same silver-plated surface layer thickness. Using plug-in terminals 40 of the same specifications, the experimental results are shown in Table 4 below.

[0107] The temperature rise test in Table 4 below involves passing the same current through the barrel terminal and the mating terminal 40 after mating. The temperature at the same location on the barrel terminal before power application and after temperature stabilization is measured in a closed environment, and the absolute value of the difference is taken. In this embodiment, a temperature rise greater than 50K is considered unqualified.

[0108] The corrosion resistance time test in Table 4 below involved placing the barrel terminal in a salt spray test chamber. Salt spray was applied to various locations on the barrel terminal. The terminal was removed for cleaning and observed for surface corrosion every 20 hours. This constituted a cycle. Testing was stopped until the surface corrosion area exceeded 10% of the total barrel terminal area. The cycle count was then recorded. In this example, cycles less than 80 were considered unsatisfactory.

[0109] Table 4: Effects of different base coating thicknesses on temperature rise and corrosion resistance of barrel terminals

[0110]

[0111] As can be seen from Table 4 above, when the thickness of the underlying nickel plating layer is less than 0.01 μm, although the temperature rise of the barrel terminal is qualified, due to the thin coating, the corrosion resistance cycle number of the barrel terminal is less than 80, which does not meet the performance requirements of the barrel terminal. This has a great impact on the overall performance and life of the docking plug. In severe cases, it causes a sudden reduction in product life or even failure and a combustion accident. When the thickness of the underlying nickel plating layer is greater than 15 μm, due to the thick underlying coating, the heat generated by the barrel terminal cannot be dissipated, making the temperature rise of the barrel terminal unqualified. Moreover, the thick coating is more likely to fall off from the terminal surface, resulting in a decrease in the number of corrosion resistance cycles. Therefore, the inventors selected a bottom coating thickness of 0.01 μm-15 μm. Preferably, the inventors found that when the bottom coating thickness is 0.1 μm-9 μm, the combined effect of the temperature rise and corrosion resistance of the barrel terminal is better. Therefore, in order to further improve the safety, reliability and practicality of the product itself, the bottom coating thickness is preferably 0.1 μm-9 μm.

[0112] To demonstrate the impact of changes in surface plating thickness on the overall performance of barrel terminals, the inventors used barrel terminal samples with the same specifications and materials, the same nickel-plated base thickness, and different silver-plated surface thicknesses, and used mating connectors of the same specifications to conduct a series of temperature rise and corrosion resistance time tests. The experimental results are shown in Table 5 below.

[0113] The experimental method is the same as the above experimental method.

[0114] Table 5: Effect of different surface coating thicknesses on temperature rise and corrosion resistance

[0115]

[0116] It can be seen from Table 5 above that when the thickness of the surface silver plating layer is less than 0.5μm, although the temperature rise of the barrel terminal is qualified, the number of corrosion resistance cycles of the barrel terminal is less than 80 because the plating layer is too thin, which does not meet the performance requirements of the barrel terminal. It has a great impact on the overall performance and life of the plug-in structure. In severe cases, it causes a sudden reduction in product life or even failure and a combustion accident. When the thickness of the surface silver plating layer is greater than 55μm, due to the thicker underlying plating layer, the heat generated by the barrel terminal cannot be dissipated, making the temperature rise of the barrel terminal unqualified, and the thicker plating layer is more likely to fall off from the terminal surface, resulting in a decrease in the number of corrosion resistance cycles. In addition, since the surface plating metal is more expensive, using a thicker plating layer does not improve the performance and has no use value. Therefore, the inventors selected a surface silver plating layer thickness of 0.1μm-55μm. Preferably, the inventors found that when the surface coating thickness is 1 μm-35 μm, the combined effect of temperature rise and corrosion resistance of the barrel terminal is better. Therefore, in order to further improve the safety, reliability and practicality of the product itself, the surface coating thickness is preferably 1 μm-35 μm.

[0117] The present application provides a barrel-type terminal that utilizes a cylindrical tube as the terminal material and injection molds the assembly portion, thereby improving the utilization rate of the terminal processing material, simplifying the processing process, shortening the processing time, and significantly reducing the production cost of the terminal. By providing a contact spring and an elastic sleeve, the barrel-type terminal not only achieves effective contact connection during use, but also effectively reduces the potential risk of electric shock injuries and equipment damage caused by poor connector structure.

[0118] Implementation Method 2

[0119] The barrel terminal in this embodiment is basically the same as the barrel terminal in the first embodiment, with the following differences:

[0120] The barrel-type terminal of the present application, as shown in FIG3 , has the slot 102 on the contact section 10 closed at both ends, and the contact spring 103 fixed at both ends. Since the contact spring 103 is fixed at both ends, the deformation of the middle contact spring 103 achieves a clamping force with the plug-in terminal 40. Compared to a contact spring 103 with one free end, this can achieve a greater clamping force and a larger contact area, ensuring that the terminal plug-in structure has better mechanical and electrical properties. However, since the contact spring 103 is fixed at both ends, there is no significant deformation, making it suitable for applications where the tolerance of the plug-in terminal 40 is small and the conduction current is large.

[0121] In the barrel terminal of the present application, the side wall of the extension section 201 is configured as a corrugated shape 205, and the assembly portion 202 is formed on the periphery of the extension section 201. When the conduction current of the barrel terminal is too large and the terminal cross-sectional area design does not have much margin, it is not suitable to open on the extension section 201 of the barrel terminal, which will reduce the cross-sectional area of ​​the barrel terminal, increase the resistance, and cause the heat generation of the barrel terminal to increase. In order to ensure that the assembly portion 202 and the extension section 201 can be firmly connected, the side wall of the extension section 201 is configured as a corrugated shape 205, and the assembly portion 202 is directly injection molded on the periphery of the extension section 201. The interior of the assembly portion 202 matches the corrugated shape 205 of the extension section 201, resulting in a larger contact area, and preventing the assembly portion 202 and the extension section 201 from axial displacement, thereby ensuring the stability of the plug-in structure.

[0122] The barrel terminal of the present application, as shown in FIG3 , has a first groove 203 provided on the outer periphery of the assembly portion 202. The barrel terminal is then placed into the mold of an injection molding machine, and the sealing ring is then injection-molded so that the sealing ring and the assembly portion 202 become one piece. This saves the sealing ring installation process, improves the possibility of assembly line automation, and also prevents the sealing ring from being missed or falling off, thus avoiding unsatisfactory sealing of the electrical device due to missed installation or falling off. Since the sealing ring and the assembly portion 202 are integrated, when the barrel terminal is installed, the sealing ring will not rub against the assembly position and fall out of the first groove 203, thereby ensuring the stability of the seal and extending the service life of the electrical device.

[0123] Implementation Method 3

[0124] The barrel terminal in this embodiment is basically the same as the barrel terminal in the second embodiment, with the following differences:

[0125] The cylindrical terminal of the present application, as shown in FIG4 , has a slot 102 on the contact section 10 that is tilted relative to the axis of the cylindrical terminal. After the cylindrical terminal is plugged into the mating terminal 40, since the slot 102 is tilted, the inside of the contact spring 103 makes spiral contact with the surface of the mating terminal 40, thereby obtaining a larger contact area, reducing the contact resistance of the plug-in structure, and ensuring reliable electrical performance. In addition, the slot 102 is tilted, thereby making the contact section 10 of the cylindrical terminal shorter while ensuring the same length and elastic force of the contact spring 103, saving terminal material, and further compressing the design space of the electrical device, making it smaller and lighter, thereby optimizing the spatial structure of the electrical device.

[0126] As shown in FIG4 , the barrel terminal of the present application has a connecting section 30 with a diameter that is less than or equal to the diameter of the contact section 10 or the extension section 201. In certain environments, the inner diameter of the barrel tube is much larger than the diameter of the conductor connection portion. In such cases, crimping or welding the connecting section 30 to the conductor will cause significant deformation of the connecting section 30, resulting in an unstable connection. Therefore, depending on the outer diameter of the conductor connection portion to which the barrel terminal is to be connected, the inner diameter of the connecting section 30 can be reduced to match the dimensions of the connecting section 30 and the conductor connection portion. This makes crimping or welding the connecting section 30 and the conductor connection portion easier and results in a more stable electrical connection.

[0127] Implementation Method 4

[0128] As shown in Figure 5 , the present application also provides a plug-in connection structure comprising a plug-in terminal 40 and the barrel terminal of Embodiment 1. The contact portion of the plug-in terminal 40 is inserted into the cavity of the barrel terminal contact section 10, and the outer wall of the plug-in terminal 40 is tightly fitted with the inner wall of the cavity of the barrel terminal contact section 10. The barrel terminal in this embodiment has the same structure, operating principle, and beneficial effects as those in Embodiment 1 and will not be further described here.

[0129] Furthermore, an insulating protective cap 401 is provided at the front end of the plug-in terminal 40 to prevent the terminal surface from melting, or the electrical device or assembly part 202 from melting, due to discharge at the contact position and excessive arc temperature when the plug-in terminal 40 is plugged into the barrel terminal.

[0130] As shown in Figure 6, a positioning hole 402 is provided at the front end of the plug-in terminal 40, and a positioning pin 207 is provided in the assembly portion 202 of the barrel terminal. The positioning pin 207 is plugged into the positioning hole 402 of the plug-in terminal 40, so that the longer plug-in terminal 40 can be positioned in the barrel terminal, so that the front end of the plug-in terminal 40 will not shake in the contact section 10 of the barrel terminal due to vibration, that is, the contact resistance change caused by shaking is prevented, and the current stability of the plug-in connection structure is maintained; it can also prevent the plug-in terminal 40 from shaking too much, causing the cables connected to the rear end of the terminal to contact each other and cause a short circuit, thereby reducing short-circuit accidents and electric shock casualties.

[0131] Implementation Method Five

[0132] As shown in FIG7 , the present application also provides a method for processing a barrel terminal, comprising:

[0133] S10. Prepare the tubular tube. The tubular tube material is selected based on the material's conductivity and elasticity requirements. The tubular tube's inner diameter is selected based on the outer diameter of the plug-in terminal 40. The tubular tube's wall thickness is selected based on the current the tubular terminal is designed to conduct. The tubular tube's length is selected based on the desired installation location.

[0134] S20. Prepare an extruder and an extrusion die. The extrusion die is divided into an inner die and an outer die. The inner die is provided with an arc-shaped depression 101 and a groove, while the outer die is provided with an arc-shaped protrusion and an extrusion shearing plate. The dimensions of the inner and outer dies match the cylindrical tube. The arc-shaped depression 101 on the inner die cooperates with the arc-shaped protrusion on the outer die to form the depression 101 on the barrel terminal contact section 10. The groove on the inner die cooperates with the extrusion shearing plate on the outer die to form the slot 102 on the barrel terminal contact section 10.

[0135] S30, placing the inner mold in the cylindrical tube, and then placing them together in the outer mold.

[0136] S40: The extruder is activated, and the arcuate protrusions of the outer die move toward the arcuate depressions of the inner die, extruding the contact section 10 of the tubular tube into an inward depression. The arcuate protrusions of the outer die are arranged circumferentially and are driven by a drive device to move toward the axis of the tubular terminal until the depression 101 of the contact section 10 is formed by extrusion.

[0137] S50: The extruder drives the extrusion and shearing stages of the outer die to continue moving, cooperating with the grooves of the inner die to extrude the contact section 10 of the cylindrical copper tube into an axial slot 102. The extrusion and shearing stages of the outer die are arranged circumferentially and are driven by a drive device to move toward the axis of the barrel terminal until the slot 102 of the contact section 10 is sheared and formed.

[0138] S60: The extruder drives the outer die to return to its original position, takes out the extruded cylindrical tube and the inner die from the outer die, and then takes out the inner die.

[0139] In some embodiments, S50 is to use a shearing device to shear or cut the contact section of the cylindrical tube into an axial groove.

[0140] Implementation Method 6

[0141] As shown in FIG8 , the present application also provides another method for processing a barrel terminal, including:

[0142] S10. Prepare the tubular tube. The tubular tube material is selected based on the material's conductivity and elasticity requirements. The tubular tube's inner diameter is selected based on the outer diameter of the plug-in terminal 40. The tubular tube's wall thickness is selected based on the current the tubular terminal is designed to conduct. The tubular tube's length is selected based on the desired installation location.

[0143] S20: Prepare a rolling machine and rolling die. The rolling die consists of an inner die and an outer die. The inner die is provided with an arc-shaped depression 101 and a groove, while the outer die is provided with an arc-shaped protrusion and a shearing plate. The dimensions of the inner and outer dies match the cylindrical tube. The arc-shaped depression on the inner die cooperates with the arc-shaped protrusion on the outer die to form the depression 101 on the barrel terminal contact section 10. The groove on the inner die cooperates with the extrusion and shearing plate on the outer die to form the slot 102 on the barrel terminal contact section 10.

[0144] S30, placing the inner mold in the cylindrical tube, and then placing them together in the outer mold.

[0145] S40: The rolling machine is activated, and the arc-shaped protrusion of the outer die moves toward the arc-shaped depression of the inner die, rolling the contact section 10 of the cylindrical tube into an inward depression. The outer die is divided into an upper die and a lower die. The lower die remains stationary, while the upper die is driven as a whole toward the lower die. By rolling the upper and lower dies relative to each other, the cylindrical tube is rolled between them, cooperating with the inner die to roll and form the depression 101 on the contact section 10.

[0146] S50 , the rolling machine drives the shearing table of the outer die to continue to move, and cooperates with the groove of the inner die to roll the contact section 10 of the cylindrical tube into an axial groove 102 .

[0147] S60, the rolling machine drives the outer mold to return to its original position, takes the rolled cylindrical tube and the inner mold out of the outer mold, and then takes out the inner mold.

[0148] In some embodiments, S50 is to use a shearing device to shear or cut the contact section of the cylindrical tube into an axial groove.

[0149] This embodiment differs from the first embodiment only in the processing equipment used; the barrel terminals produced are the same.

[0150] Implementation Method Seven

[0151] As shown in FIG9 , the present application also provides another method for processing a barrel terminal, including:

[0152] The processing method of this embodiment is basically the same as that of the fifth and sixth embodiments, except that after step S40, it further includes step S45, in which the outer mold moves toward the inner mold to extrude the extended section of the cylindrical tube into an assembly portion.

[0153] Implementation Method Eight

[0154] As shown in FIG10 , the present application also provides another method for processing a barrel terminal, including:

[0155] The processing method of this embodiment is basically the same as that of the fifth and sixth embodiments, except that after step S50, it also includes step S56, in which an opening is cut out on the extension section 201, which can be extruded or rolled together with the groove 102 on the contact section 10.

[0156] Implementation Method Nine

[0157] As shown in FIG11 , the present application also provides another method for processing a barrel terminal, including:

[0158] The processing method of this embodiment is basically the same as that of the fifth and sixth embodiments, except that after step S50, it also includes step S57, in which the corrugation 205 is extruded or rolled on the extension section 201, and can be extruded or rolled together with the recess 101 on the contact section 10 to form the corrugation 205.

[0159] Implementation Method 10

[0160] As shown in FIG12 , the present application also provides another method for processing a barrel terminal, including:

[0161] The processing method of this embodiment is basically the same as that of the fifth and sixth embodiments, except that after step S50, it further includes step S70, placing the extruded or rolled cylindrical tube into an injection molding machine and injection molding it into an assembly part.

[0162] Implementation Method Eleven

[0163] As shown in FIG13 , the present application also provides another method for processing a barrel terminal, including:

[0164] The processing method of this embodiment is basically the same as that of the fifth and sixth embodiments, except that after step S50, step S58 is further included to extrude or roll out the second groove 104 on the contact segment 10, which can be extruded or rolled together with the depression 101 on the contact segment 10.

[0165] Implementation Method Twelve

[0166] As shown in FIG14 , the present application also provides another method for processing a barrel terminal, including:

[0167] The processing method of this embodiment is basically the same as that of the fifth and sixth embodiments, except that after step S50, step S59 is further included to extrude or roll the connecting section 30 until its diameter is reduced, and the connecting section 30 can be extruded or rolled together with the recess 101 on the contact section 10 to form the connecting section 30.

[0168] Implementation Method Thirteen

[0169] As shown in FIG15 , the present application also provides another method for processing a barrel terminal, including:

[0170] The processing method of this embodiment is substantially the same as that of the fifth and sixth embodiments, except that after step S60 , the method further includes step S66 , in which a plating layer is provided at least on the contact section 10 and / or the connecting section 30 .

[0171] Implementation Method 14

[0172] As shown in FIG16 , the present application also provides another method for processing a barrel terminal, including:

[0173] The processing method of this embodiment is substantially the same as that of the fifth and sixth embodiments, except that it further includes step S80 after step S60: placing the molded barrel terminal into an injection molding machine to injection-mold the sealing ring.

[0174] Implementation Method 15

[0175] As shown in FIG17 , the present application also provides another method for processing a barrel terminal, including:

[0176] The processing method of this embodiment is substantially the same as that of the fifth and sixth embodiments, except that after step S60 , the method further includes step S90 : assembling a sealing ring in the first groove 203 .

[0177] Implementation Method 16

[0178] As shown in FIG18 , the present application also provides another method for processing a barrel terminal, including:

[0179] The processing method of this embodiment is substantially the same as that of the fifth and sixth embodiments, except that it further includes step S100 after step S70 : assembling the elastic assembly 105 in the second groove 104 .

[0180] Although the implementation scheme of the present application has been disclosed as above, it is not limited to the applications listed in the description and implementation mode. It can be fully applied to various fields suitable for the present application. For those familiar with this field, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present application is not limited to the specific details and illustrations shown and described herein.

Claims

1. A cylindrical terminal, in, Includes: contact section, fixed section, and connecting section. The fixed section includes an extension section and a mounting portion disposed on the extension section; The contact section, the extension section, and the connecting section are integrally formed into a cylindrical tube; At least two axial slots are provided on the contact section, so that the sidewall of the contact section is divided into at least two contact spring pieces; The contact section is radially recessed inward, so that the contact spring forms an arc-shaped structure; The connecting segment is electrically connected to the conductor.

2. The cylindrical terminal according to claim 1, wherein, The slot extends through the side of the contact section away from the fixed section, and one end of the contact spring is a free end.

3. The cylindrical terminal according to claim 1, wherein, The slot is closed at both ends, and the contact spring is fixed at both ends.

4. The cylindrical terminal according to claim 1, wherein, The width of the slot on the side closer to the fixed section is greater than or equal to the width on the side farther from the fixed section.

5. The cylindrical terminal according to claim 1, wherein, The slot is inclined relative to the axis of the cylindrical terminal.

6. The cylindrical terminal according to claim 1, wherein, The assembly section is formed by extruding the extension section.

7. The cylindrical terminal according to claim 1, wherein, The assembly part is made of plastic and is installed on the extension section by injection molding.

8. The cylindrical terminal according to claim 7, wherein, The extension section is provided with an opening, which allows the assembly part to be integrated inside and outside the cylindrical tube.

9. The cylindrical terminal according to claim 7, wherein, The sidewall of the extension section is corrugated, and the assembly part is formed on the outer periphery of the extension section.

10. The cylindrical terminal according to claim 1, wherein, The tubular tube is either a seamless tube or a seamed tube made of rolled sheet metal.

11. The cylindrical terminal according to claim 10, wherein, When the tubular tube is a slotted tube, there must be no seam on the contact spring.

12. The cylindrical terminal according to claim 1, wherein, The inner cross-sectional shape of the inner surface of the arc-shaped structure is circular, elliptical, polygonal, flat, E-shaped, F-shaped, H-shaped, K-shaped, L-shaped, T-shaped, U-shaped, V-shaped, W-shaped, X-shaped, Y-shaped, Z-shaped, semi-arc, arc-shaped, or wavy.

13. The cylindrical terminal according to claim 1, wherein, The inner surface of the arc-shaped structure is at the same distance from the axis of the cylindrical terminal.

14. The cylindrical terminal according to claim 1, wherein, The diameter of the connecting segment is less than or equal to the diameter of the contact segment or the extension segment.

15. The cylindrical terminal according to claim 1, wherein, The end of the contact segment away from the fixed segment is provided with an outwardly expanding chamfer, the angle of which ranges from 17° to 178°.

16. The cylindrical terminal according to claim 1, wherein, The cylindrical tube is made of copper or copper alloy, or aluminum or aluminum alloy.

17. The cylindrical terminal according to claim 16, wherein, When the cylindrical tube is made of copper alloy, the copper material contains tellurium.

18. The cylindrical terminal according to claim 17, wherein, The tellurium content in the tubular material is 0.1%-5%.

19. The cylindrical terminal according to claim 1, wherein, The assembly part has a first groove on its outer periphery, and the cylindrical terminal also includes a sealing ring sleeved on the first groove, the sealing ring being made of rubber.

20. The cylindrical terminal according to claim 1, wherein, The outer side of the contact segment has a second groove arranged circumferentially, and the cylindrical terminal also includes an elastic sleeve sleeved on the second groove, the elastic sleeve being made of rubber.

21. The cylindrical terminal according to claim 1, wherein, A plating layer is provided at least partially on the contact section and / or the connection section.

22. The cylindrical terminal according to claim 21, wherein, The coating material is one or more of the following: gold, silver, nickel, tin, tin-lead alloy, zinc, silver-antimony alloy, palladium, palladium-nickel alloy, graphite silver, graphene silver, and silver-gold-zirconium alloy.

23. The cylindrical terminal according to claim 22, wherein, The coating includes a base layer and a surface layer.

24. The cylindrical terminal according to claim 23, wherein, The bottom layer material is one or more of gold, silver, nickel, tin, tin-lead alloy and zinc; the surface layer material is one or more of gold, silver, nickel, tin, tin-lead alloy, zinc, silver-antimony alloy, palladium, palladium-nickel alloy, graphite silver, graphene silver and silver-gold-zirconium alloy.

25. The cylindrical terminal according to claim 23, wherein, The thickness of the bottom layer is 0.01μm-15μm.

26. The cylindrical terminal according to claim 23, wherein, The thickness of the bottom layer is 0.1μm-9μm.

27. The cylindrical terminal according to claim 23, wherein, The thickness of the surface layer is 0.5μm-55μm.

28. The cylindrical terminal according to claim 23, wherein, The thickness of the surface layer is 1μm-35μm.

29. A plug-in connection structure, wherein, The interlocking connection structure includes an interlocking terminal and a cylindrical terminal as described in any one of claims 1 to 28, wherein the interlocking terminal is inserted into the contact section, and the outer side wall of the interlocking terminal is in close contact with the inner side wall of the contact spring.

30. A plug-in connection structure according to claim 29, wherein: The cylindrical terminal has a positioning pin inside its assembly part, and the front end of the plug-in terminal has a positioning hole, with the positioning pin inserted into the positioning hole.

31. A processing method for manufacturing a cylindrical terminal as described in any one of claims 1-28, in, include: S10. Preparation of cylindrical tubes; S20. Prepare the extruder and the mold. The mold is divided into an inner mold and an outer mold. The inner mold is provided with an arc-shaped recess and a first groove. The outer mold is provided with an arc-shaped protrusion and a shearing table. S30. Place the inner mold in the cylindrical tube, and then put them together into the outer mold; S40. Start the extruder. The arc-shaped protrusion of the outer die moves towards the arc-shaped concave part of the inner die, extruding the contact section of the cylindrical tube into an inward concave shape. S50, the extruder drives the outer die shearing table to continue moving, cooperating with the first groove of the inner die to extrude the contact section of the cylindrical tube into an axial slot. S60. The extruder drives the outer mold to return to its original position, removes the extruded cylindrical tube and inner mold from the outer mold, and removes the inner mold.

32. The method for processing the cylindrical terminal according to claim 31, wherein, The extruder in steps S20, S40, S50 and S60 is a rolling mill.

33. The method for processing the cylindrical terminal according to claim 31 or 32, wherein, Step S50 is to cut or shear the contact section of the cylindrical tube to create an axial groove.

34. The method for processing the cylindrical terminal according to claim 31 or 32, wherein, After step S40, there is also step S45, in which the outer mold moves to the inner mold to extrude the extension of the cylindrical tube into an assembly.

35. The method for processing the cylindrical terminal according to claim 31 or 32, wherein, Following step S50, step S56 is also included, in which an opening is cut out on the extension segment.

36. The method for processing a cylindrical terminal according to claim 31 or 32, wherein, Following step S50, step S57 is also included, in which corrugations are extruded or rolled onto the extension.

37. The method for processing a cylindrical terminal according to claim 31 or 32, wherein, After step S60, step S70 is also included, in which the extruded or rolled cylindrical tube is placed into an injection molding machine and injection molded into an assembly part.

38. The method for processing a cylindrical terminal according to claim 31 or 32, wherein, Following step S50, step S58 is also included, in which a second groove is pressed or rolled out on the contact segment.

39. The method for processing a cylindrical terminal according to claim 31 or 32, wherein, Following step S50, step S59 is also included, in which the connecting segment is squeezed or rolled to reduce its diameter.

40. The method for processing a cylindrical terminal according to claim 31 or 32, wherein, Following step S60, step S66 is also included, whereby a plating layer is applied at least on the contact segment and / or the connecting segment.

41. The method for processing a cylindrical terminal according to claim 31 or 32, wherein, Step S60 is followed by step S80: the extruded or rolled tubular tube is placed into the injection molding machine to injection mold a sealing ring.

42. The method for processing the cylindrical terminal according to claim 31 or 32, wherein, The process includes step S90 after step S60: assembling a sealing ring in the first groove.

43. The method for processing a cylindrical terminal according to claim 38, wherein, The step S60 is followed by step S100: assembling the elastic kit in the second groove.

Images