Stamping connection terminal and preparation method thereof

Abstract

The invention discloses a stamping connection terminal and a preparation method thereof, and relates to the technical field of electric appliance connection terminals. The stamping connection terminal is integrally formed by continuously stamping a high-precision phosphor copper strip, and comprises a contact end and a connection end. The contact end comprises a pair of elastic contact arms which are oppositely arranged, the free end of each elastic contact arm is bent to form a guide flange with a guide surface, and a plurality of hemispherical contact salient points are arranged at the junction of the guide surface and the elastic contact arms. The connecting end is provided with a clamping structure, and the clamping structure is provided with at least two rows of antiskid teeth which are distributed in a staggered mode. And a transition region between the contact end and the connection end. The surface of the contact end is provided with a gold-plated layer, and the surfaces of the connecting end and the transition area are provided with a mist tin-plated layer. The purity of the high-precision phosphorus copper strip is larger than or equal to 99.95%, the content of phosphorus is 0.03-0.08 wt%, the tensile strength is 350-400 MPa, and the ductility is larger than or equal to 15%. According to the invention, the problems that the connection is not tight enough, the conductive performance is not stable and the preparation cost is high in the actual use process of the current connection terminal can be effectively improved.

Description

Technical Field

[0001] This application relates to the technical field of electrical connection terminals, and more particularly to a stamped connection terminal and its manufacturing method. Background Technology

[0002] As electronic devices develop towards miniaturization, high density, and high-frequency plugging and unplugging, the reliability of contact, smoothness of plugging and unplugging, structural stability, and cost control of connection terminals, as core conductive connectors, have become the core demands of the industry.

[0003] Currently, the forming process of connector terminals mostly adopts split stamping followed by assembly or low-precision continuous stamping, which not only leads to poor dimensional accuracy and insufficient structural consistency of the terminals, but also results in small contact areas and large fluctuations in contact resistance due to the predominantly planar contact ends. Furthermore, the use of integral gold plating for connector terminals typically results in high consumption of precious metals and high costs. Therefore, it is evident that current stamped connector terminals still suffer from problems such as insufficiently tight connections, unstable conductivity, and high manufacturing costs in practical applications. Summary of the Invention

[0004] The purpose of this invention is to provide a stamped connecting terminal and its manufacturing method, which can solve the above-mentioned problems existing in the prior art.

[0005] To achieve the above objectives, this application adopts the following technical solution: On one hand, a stamped connecting terminal is provided, which is integrally formed from high-precision phosphor bronze strip by continuous stamping, comprising: The contact end, used to achieve electrical connection with the adapter connector, includes a pair of oppositely arranged elastic contact arms. The free ends of the elastic contact arms are bent to form guide flanges with guide surfaces. Multiple hemispherical contact protrusions are provided at the junction of the guide surfaces and the elastic contact arms. Each contact protrusion is arranged along the insertion and extraction direction, and the center distance between adjacent contact protrusions is 0.3-0.5 mm. The height of the protrusions increases by 0.02-0.03 mm from the insertion / extraction inlet inwards. A connecting end is used for fixed connection with a cable or circuit board. The connecting end is provided with a snap-fit ​​structure, and the snap-fit ​​structure is provided with at least two rows of staggered anti-slip teeth. And, a transition region located between the contact end and the connection end, wherein the cross-sectional area of ​​the transition region is larger than the cross-sectional area of ​​the contact end and the connection end; The contact end has a gold plating layer on its surface, and the connection end and transition area have a matte tin plating layer on their surfaces; and The high-precision phosphorus copper strip has a purity of ≥99.95%, a phosphorus content of 0.03-0.08wt%, a tensile strength of 350-400MPa, and an elongation of ≥15%.

[0006] Optionally, the stamped connecting terminal is a socket terminal, the contact end of the socket terminal is a socket structure constructed by two symmetrically arranged elastic contact arms, the inner surface of the two elastic contact arms is fully covered by the gold plating layer, and the free end of the elastic contact arm is an outwardly turned guide flange forming a flared structure.

[0007] Optionally, the stamped connection terminal is a pin terminal, and the contact end of the pin terminal is a pin structure constructed by two symmetrically arranged elastic contact arms. The outer surface of the elastic contact arms is covered with the gold plating layer, and the free end of the elastic contact arms is an inwardly turned guide flange that forms a closed structure.

[0008] Optionally, the connecting end is provided with a cable riveting area for riveting with a cable, and the snap-fit ​​structure is located in the cable riveting area; The snap-fit ​​structure includes a crimping groove, and a first crimping plate and a second crimping plate are respectively provided on the side of the crimping groove; and The anti-slip teeth are disposed on the surface of the first pressing plate, the second pressing plate, or the bottom of the pressing groove, and are distributed in an obliquely staggered manner.

[0009] Optionally, the stamped connecting terminal is a row spacing terminal, and the contact end of the row spacing terminal is a pair of elastic contact arms facing each other, with a clamping gap formed between the two elastic contact arm springs.

[0010] Optionally, the connection end is provided with a cable board junction area, and the snap-fit ​​structure is located in the cable board junction area; The snap-fit ​​structure includes a pin, the free end of which is provided with a 30°-45° angled guide portion; and the side of the columnar section of the pin is provided with a micro-groove.

[0011] Optionally, the thickness of the gold plating layer is 0.5-2μm, and a nickel underlay layer with a thickness of 1-3μm is provided under the gold plating layer; The gold plating layer has a density ≥99.5% and a porosity ≤0.1 particles / mm²; and The thickness of the matte tin layer is 5-15 μm, and the purity of the tin layer is ≥99.9%.

[0012] Optionally, the connection between the connecting end and the transition zone is provided with a stress relief groove.

[0013] This disclosure also provides a method for preparing a stamped connecting terminal as described in any of the above, comprising: Step S10: Pre-treat the high-precision phosphor bronze strip that meets the condition parameters, including: degreasing with 5%-8% alkaline degreasing agent at 50-60℃ for 10-15 minutes, removing rust with 10%-15% hydrochloric acid solution for 5-8 minutes, rinsing with pure water and drying. Step S20: Using a continuous stamping die with an accuracy of ±0.005mm, the pre-treated high-precision phosphor bronze is sequentially punched, bent, and partially formed to obtain a stamped connection terminal including a contact end and a connection end. Step S30: A gold plating layer is plated onto the contact end of the stamped connection terminal under the conditions of a current density of 1-3 A / dm² and an electroplating solution temperature of 40-50°C. Step S40: The connecting end and transition area of ​​the stamped connecting terminal are plated with a mist tin layer under the conditions of a current density of 1-2A / dm² and an electroplating solution temperature of 25-35℃. Step S50: After electroplating, rinse with pure water and dry at 80-100℃ for 5-10 minutes.

[0014] Optionally, in step S20, the blanking clearance of the continuous stamping die is controlled to be 0.01-0.02 mm, and the bending radius matches the transition radius of the stamping connection terminal; and In step S30, before gold plating the contact end, the method further includes: activating the contact end with a 5%-8% sulfuric acid solution, and first preparing a nickel underlayer using a sulfate nickel plating process.

[0015] The beneficial effects of this application are as follows: The one-piece molding process eliminates the gaps caused by the separate assembly of stamped connectors. Combined with the gradient contact protrusions of the elastic contact arm, it forms progressive contact pressure, ensuring a tight fit between the mating parts and reducing contact gaps and the risk of loosening. The diagonally interlocking anti-slip teeth create a multi-dimensional interlocking structure, thereby increasing locking force and effectively resisting loosening under pulling and vibration conditions. Simultaneously, it distributes force to prevent tooth tip deformation, ensuring long-term stable connection. The gradient contact protrusions and the elastic contact arm deform in synergy, automatically compensating for minor dimensional deviations in the mating parts. Even if some contact protrusions wear slightly, higher-height contact protrusions can still maintain effective contact, adapting to high-frequency insertion and removal scenarios. The structure combined with the guide flange enables automatic alignment of the mating parts, reducing the difficulty of initial alignment during insertion and removal, reducing insertion force, and avoiding structural damage caused by forced insertion.

[0016] Leveraging the excellent conductivity of high-precision phosphor bronze strips, combined with a dense gold plating layer at the contact points, contact resistance is significantly reduced, minimizing current transmission loss. Simultaneously, the optimal ratio of phosphorus to high-purity copper ensures minimal contact resistance fluctuations across a wide temperature range of -40℃ to 125℃, making it suitable for extreme environments. Furthermore, a nickel undercoat prevents copper-gold diffusion, enhances the adhesion of the gold plating layer, and results in low plating peeling after high and low temperature cycling, preventing conductivity degradation caused by oxidation and sulfidation. By using localized gold plating—that is, using precious metals only in the most critical and performance-required contact areas, while using cost-effective matte tin plating in non-functional areas—a balance between performance and cost is achieved. Attached Figure Description

[0017] The present application will now be described in further detail with reference to the accompanying drawings and embodiments.

[0018] Figure 1 This is a schematic diagram of the structure of a punched connection terminal as a socket terminal according to an embodiment of this application; Figure 2 This is a front view of a schematic diagram showing that the stamped connecting terminal is a socket terminal according to an embodiment of this application; Figure 3 This is a partially enlarged structural diagram of the contact end of a socket terminal as described in an embodiment of this application; Figure 4 for Figure 3 An enlarged structural diagram of point A in the scheme; Figure 5 This is a schematic diagram of the structure of a stamped connecting terminal as a pin terminal according to an embodiment of this application; Figure 6 This is a partially enlarged structural diagram of the contact end of a pin terminal as described in an embodiment of this application; Figure 7 This is a schematic diagram of the structure of the connection end of an embodiment of the stamped connection terminal described in this application; Figure 8 This is a schematic diagram of the structure of a stamped connecting terminal as a row-pitch terminal according to an embodiment of this application; Figure 9 This is a top view of a structural diagram showing that the stamped connecting terminal is a row-spaced terminal according to an embodiment of this application; Figure 10 This is a partially enlarged structural schematic diagram of the contact end of the stamped connecting terminal as a row-pitch terminal according to an embodiment of this application; Figure 11 This is a partial structural diagram of a pin of a row-pitch terminal as described in one embodiment of this application; Figure 12 This is a schematic diagram of the release groove structure of the stamped connection terminal as a row spacing terminal according to an embodiment of this application; Figure 13 This is a schematic flowchart of a method for preparing a stamped connecting terminal according to an embodiment of this application.

[0019] In the picture: 100. Contact end; 110. Elastic contact arm; 120. Guide flange; 121. Guide surface; 122. Contact protrusion; 200. Connecting end; 210. Snap-fit ​​structure; 211. Anti-slip teeth; 300. Transition zone; 310. Release groove; 400, gold plating; 401, nickel base coat; 410, matte tin plating; 10. Socket terminal; 11. Flared structure; 12. Cable riveting area; 13. Crimping groove; 14. First crimping plate; 15. Second crimping plate; 20. Pin terminal; 21. Closed structure; 30. Spacing terminal; 31. Clamping gap; 32. Cable board junction area; 33. Pin; 34. Angled guide; 35. Micro-groove. Detailed Implementation

[0020] To make the technical problems solved by this application, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the embodiments of this application are further described in detail below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] In the description of this application, unless otherwise expressly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0023] like Figures 1 to 12 As shown, this embodiment provides a stamped connection terminal, which can be used to improve the problems of insufficient connection, unstable conductivity and high manufacturing cost of existing stamped connection terminals in actual use.

[0024] The stamped connector provided in this application is integrally formed from high-precision phosphor bronze strip through continuous stamping. It includes a contact end 100 and a connecting end 200. The contact end 100 is used to achieve electrical connection with a suitable connector, and the connecting end 200 is used to connect with a cable or circuit board. By using high-precision phosphor bronze strip for continuous stamping and integral forming, the connector can be made without gaps in the assembly of separate parts, and the structure is more compact, thereby reducing problems such as poor contact that may occur due to the combination of multiple parts. At the same time, the integral forming process can also reduce the risk of stress concentration, ensuring that the terminal is not easily deformed or broken under insertion, removal, or vibration conditions.

[0025] Specifically, the contact end 100 includes a pair of opposing elastic contact arms 110. The free end of the elastic contact arm 110 is bent to form a guide flange 120 with a guide surface 121. Multiple hemispherical contact protrusions 122 are provided at the junction of the guide surface 121 and the elastic contact arm 110. The guide flange 120 and the guide surface 121 at the free end of the elastic contact arm 110 can form a natural guiding structure, thereby reducing the difficulty of alignment during the initial insertion and removal process. The contact protrusions 122 are arranged along the insertion and removal direction, and the center distance between adjacent contact protrusions 122 is 0.3-0.5 mm. The height of the contact protrusions 122 increases by 0.02-0.03 mm from the insertion / removal inlet inwards.

[0026] Understandably, by progressively increasing the height of the contact bumps 122 along the insertion / removal direction, a gradient contact pressure can be formed. Specifically, in the initial stage of insertion / removal, the lower-height contact bumps 122 make contact first to achieve positioning, and as insertion progresses, the higher-height contact bumps 122 gradually increase the contact pressure, ensuring a tight fit with the mating parts and reducing contact gaps. The hemispherical contact bumps 122 can also adapt to minor unevenness on the surface of the mating parts through slight deformation, increasing the actual contact area and reducing contact resistance fluctuations. At the same time, the contact bumps 122 can also reduce the friction area of ​​the contact region, and the hemispherical shape can reduce local stress concentration during insertion / removal. Combined with the buffering effect of the elastic contact arm 110, it can effectively reduce wear on the contact surface caused by high-frequency insertion / removal.

[0027] It is important to note that the progressively increasing height of the contact bumps 122 and the deformation characteristics of the elastic contact arm 110 work synergistically. Specifically, when there are slight dimensional deviations in the mating parts, contact bumps 122 of different heights can contact the mating parts separately. Through the deformation of the contact bumps 122 themselves and the elastic adjustment of the contact arm, the deviation is automatically compensated, ensuring that at least some of the contact bumps 122 always maintain effective contact. Simultaneously, the contact bumps 122 and the progressively increasing height ensure that wear in the contact area during insertion and removal is distributed across multiple contact bumps 122, rather than concentrated on a single contact surface. Even if some contact bumps 122 experience slight wear, subsequent contact bumps 122 of higher heights can still maintain effective contact.

[0028] Furthermore, the connection end 200 is provided with a snap-fit ​​structure 210, which has at least two rows of staggered anti-slip teeth 211. Understandably, the at least two rows of staggered anti-slip teeth 211 can form a multi-dimensional interlocking structure, thereby significantly improving the friction and locking force of the snap-fit ​​structure 210, effectively preventing the terminal from loosening under pulling or vibration conditions. At the same time, the staggered anti-slip teeth 211 can distribute the force to multiple tooth tips, avoiding tooth tip deformation or detachment caused by localized force concentration in a single row of teeth, ensuring that the snap-fit ​​structure 210 can maintain a stable connection even when subjected to cable tension or board connection pressure for a long period.

[0029] Furthermore, a transition zone 300 is provided between the contact end 100 and the connection end 200. The cross-sectional area of ​​the transition zone 300 is larger than that of the contact end 100 and the connection end 200. Specifically, because the cross-sectional area of ​​the transition zone 300 is larger than that of the contact end 100 and the connection end 200, it can effectively disperse the stress caused by insertion / removal, vibration, and cable pulling, avoiding terminal breakage due to stress concentration. At the same time, the larger cross-sectional area of ​​the transition zone 300 not only enhances its own fracture resistance but also buffers the mutual transmission of insertion / removal stress at the contact end 100 and fixing stress at the connection end 200. For example, the elastic deformation stress of the contact end 100 during insertion / removal, after being dispersed by the transition zone 300, will not directly act on the connection end 200, preventing the connection between the connection end 200 and the cable / circuit board from becoming loose.

[0030] Furthermore, the surface of the contact end 100 is provided with a gold plating layer 400, and the surfaces of the connecting end 200 and the transition area 300 are provided with a matte tin plating layer 410. At the same time, the high-precision phosphor bronze strip has a purity of ≥99.95%, a phosphorus content of 0.03-0.08wt%, a tensile strength of 350-400MPa, and an elongation of ≥15%.

[0031] Specifically, high-precision phosphor bronze strips with a tensile strength of 350-400 MPa and an elongation of ≥15% can effectively meet the processing requirements of continuous stamping, while ensuring the overall structural stability of the terminal and preventing deformation. Meanwhile, the gold plating layer 400 on the contact end 100 ensures low resistance and high wear resistance in critical electrical contact areas, and combined with the high conductivity of the high-precision phosphor bronze strip, further reduces current transmission loss. By plating a matte tin layer 410 on the connection end 200 and the transition area 300, the consumption of precious metals is significantly reduced while meeting corrosion resistance requirements, lowering overall manufacturing costs and resolving the contradiction between the high cost of full gold plating and the poor conductivity of full tin plating.

[0032] It is important to note that the ratio of 0.03-0.08 wt% phosphorus to high-purity copper in the high-precision phosphorus copper strip can improve the temperature adaptability of the connection terminals. Specifically, it can effectively reduce the contact resistance fluctuation of the connection terminals within a wide temperature range of -40℃ to 125℃. Simultaneously, the adhesion between the gold plating layer 400 and the phosphorus copper substrate is synergistically enhanced due to the interfacial bonding effect promoted by phosphorus, effectively reducing the plating peeling rate after high and low temperature cycling.

[0033] Please see Figures 1 to 4 In one embodiment, the stamped connection terminal is a socket terminal 10, the contact end 100 of which is constructed by two symmetrically arranged elastic contact arms 110, forming a socket structure. The inner surfaces of the two elastic contact arms 110 are fully covered with a gold plating layer 400, and the guide flange 120 at the free end of the elastic contact arm 110 is turned outward to form a flared structure 11.

[0034] For example, when the stamped connection terminal is a socket terminal 10, its matching connectors for connection are inserted into the socket terminal 10 to achieve mutual connection between the two. Specifically, the socket terminal 10 can accommodate cylindrical or blade-shaped pins to form a reliable and stable circuit connection.

[0035] Furthermore, the contact end 100 of the socket terminal 10 is composed of two symmetrical elastic contact arms 110, which extend from the transition area 300 and together form an approximately elliptical or rectangular socket structure. The two symmetrically arranged elastic contact arms 110 ensure even force distribution in all directions, preventing pin misalignment and wear due to unilateral force, thus guaranteeing connection concentricity. A full-area gold plating layer 400 can be applied to the inner contact surfaces of the two elastic contact arms 110. That is, from the root of the contact arm to the guide flange 120 at its free end, the entire area that may contact the pin is protected by the gold plating layer 400. Because gold has excellent chemical inertness and effectively prevents surface oxidation and sulfidation, it ensures that the contact resistance remains extremely low and stable throughout the entire insertion / removal stroke and during use.

[0036] Furthermore, the free end of each elastic contact arm 110 undergoes a bending process, folding it outward to form a smooth guide surface 121. The two guide flanges 120 together constitute a wide-inlet, gradually converging, flared structure 11. When a pin attempts to insert, regardless of its alignment accuracy, this flared structure 11 first captures the pin's tip and uses its guide surface 121 to automatically guide and center the pin to the center of the socket. Therefore, the initial insertion force is greatly reduced, and terminal damage or pin wear caused by the pin hitting the edge of the contact arm is effectively prevented, improving assembly compatibility and reliability.

[0037] Furthermore, as mentioned earlier, a plurality of hemispherical contact protrusions 122 are provided on the inner guide surface 121 of the guide flange 120 in a gradient distribution. The array formed by the internal contact protrusions 122 can ensure stable contact and ensure the reliability of clamping and connection.

[0038] Understandably, the connection terminals disclosed in this embodiment have excellent insertion and removal guidance and ease of operation, significantly reducing insertion difficulty and alignment accuracy requirements, making the assembly process of the connection terminals fast and smooth. Simultaneously, the outward-flared guide flange 120 and the flared structure 11 achieve automatic pin alignment. They also provide durable, stable, low contact resistance throughout the entire contact area, ensuring high-quality signal and current transmission. Furthermore, the full-area gold plating layer 400 on the inner side of the elastic contact arm 110 effectively prevents oxidation and fretting corrosion in the contact area.

[0039] Please see Figure 5 and Figure 6 In one embodiment, the stamped connection terminal is a pin terminal 20, and its contact end 100 is a pin structure constructed by two symmetrically arranged elastic contact arms 110. The outer surface of the elastic contact arm 110 is covered with a gold plating layer 400, and the guide flange 120 of the free end of the elastic contact arm 110 is turned inward to form a closed structure 21.

[0040] For example, the pin terminal 20 provided in this application is used to insert into a corresponding socket to achieve a circuit connection. In this embodiment, the contact end 100 is constructed by two symmetrical elastic contact arms 110 facing each other to form an insertable solid structure. Compared with conventional rigid pins, the pin terminal 20 can continuously apply a uniform and gentle radial pressure to the inner wall of the socket after insertion by relying on the deformation of its own elastic contact arms 110, thereby compensating for manufacturing tolerances and wear and ensuring a tight connection.

[0041] Furthermore, a full-coverage gold plating layer 400 is provided on the outer surface of the two elastic contact arms 110. The gold plating layer 400 ensures good resistance to environmental corrosion throughout the entire contact area with the inner wall of the socket. Therefore, it can fundamentally avoid the increase in contact resistance caused by surface oxidation, making it suitable for signal connections requiring high reliability.

[0042] Furthermore, the free end of each elastic contact arm 110 is bent and then folded inward to form a smooth guide surface 121. Two guide flanges 120 approach or contact each other at the tip of the pin, forming a converging or closed head structure. When the pin terminal 20 is inserted into the socket, its head structure forms a smooth and continuous guide structure. This guide structure can easily slide into the flared opening of the mating socket and quickly guide the pin, significantly reducing the initial insertion force. Understandably, the inwardly folded guide flange 120 can wrap around sharp, easily deformable sheet edges, preventing the head of the pin terminal 20 from "blowing" or "opening" due to impact, thus protecting the integrity of the terminal. At the same time, the head structure effectively prevents the head of the pin terminal 20 from being squeezed and deformed due to improper force, ensuring the strength and insertion / removal life of the pin terminal 20.

[0043] Furthermore, multiple hemispherical contact bumps 122 are provided on the guide surface 121 on the outer side of the guide flange 120 in a gradient distribution. When the pin is inserted, these contact bumps 122 will serve as the first contact point, which can pierce the possible oxide layer on the inner wall of the socket and establish a low-resistance metallic contact.

[0044] Please see Figure 1 , Figure 5 and Figure 7 In one embodiment, the connecting end 200 is provided with a cable riveting area 12 for riveting with a cable. The snap-fit ​​structure 210 is located in the cable riveting area 12 and includes a crimping groove 13. A first crimping plate 14 and a second crimping plate 15 are respectively provided on the side of the crimping groove 13. Anti-slip teeth 211 are provided on the surface of the first crimping plate 14, the second crimping plate 15 or the bottom of the crimping groove 13, and are distributed obliquely and alternately.

[0045] For example, the core structure of the cable riveting area 12 provided at the connection end 200 is a crimping groove 13. This crimping groove 13 is typically U-shaped or V-shaped to accommodate cable conductors of specific specifications after the insulation has been stripped. Preferably, in this embodiment, the crimping groove 13 is U-shaped. During the crimping process, the first crimping plate 14 and the second crimping plate 15 are bent and snapped together using special tools, thereby tightly wrapping and compressing the cable conductor within the crimping groove 13, forming a robust mechanical connection and a low-resistance electrical path.

[0046] Furthermore, by employing an obliquely staggered anti-slip tooth arrangement 211 on the first crimping plate 14, the second crimping plate 15, or the bottom surface of the groove, the teeth penetrate or embed into the multi-stranded cable conductor from multiple directions. Regardless of the direction of the pulling force applied to the cable, there is always a set of obliquely staggered anti-slip teeth 211 that provides effective resistance. Understandably, the obliquely staggered anti-slip teeth 211 can form a three-dimensional, asymmetrical mechanical interlocking network inside the conductor, greatly increasing the resistance to cable pull-out. Simultaneously, even if the engagement effect of individual anti-slip teeth 211 is poor, the numerous other staggered anti-slip teeth 211 still ensure overall connection performance, significantly improving product yield and reliability.

[0047] Please see Figures 8 to 12 In one embodiment, the stamped connection terminal is a row-spaced terminal 30, whose contact end 100 is made of a high-precision phosphor bronze strip with an initial thickness of 0.6 mm, which is flattened to a thickness of 0.4 mm through three stepped stamping processes, and then formed by stamping and tearing to form a pair of upper and lower opposing elastic contact arms 110, with a clamping gap 31 formed between the two elastic contact arms 110 spring sheets.

[0048] For example, in this embodiment, the stamped connection terminal is a row-gap terminal 30, which is suitable for high-density, plate-to-plate connections or clamp-type connections. It should be noted that the contact end 100 of the row-gap terminal 30 is not directly stamped from the original thickness of the strip. First, a high-precision phosphor bronze strip with an initial thickness of 0.6 mm is used, and through a set of precision continuous dies, it undergoes three stepped progressive stamping processes to stably flatten its critical contact area to a final thickness of 0.4 mm. For example, in the actual stamping process, it is permissible to press to 0.55 mm the first time, 0.47 mm the second time, and the target thickness of 0.4 mm the third time. This multi-stamping process avoids problems such as damage to the internal grain structure of the material, microcracks, or excessive residual stress caused by excessive deformation in a single step. After the material is flattened to 0.4 mm, an elastic contact arm 110 is formed through a stamping tearing process. This results in a pair of elastic contact arms 110 that are vertically opposed and integrally formed. A clamping gap 31 is naturally formed between the two elastic contact arms 110 formed by the tearing process. When the accessory is inserted, the elastic contact arms 110 deform and apply a stable and uniform vertical clamping force to the inserted object by relying on the rebound force of the material itself.

[0049] Understandably, the flexible contact arm 110 is completely integrated with the terminal body through a tearing process, eliminating any potential weaknesses caused by welding or riveting. This ensures a smooth force transmission path and uniform stress distribution, thus solving the problem of easy breakage at the root of the connecting arm. Simultaneously, the entire contact end 100 is precision-machined from a single flat material, requiring no additional parts or complex three-dimensional bending, minimizing the space occupied in the width and height directions of the connector.

[0050] Please refer to the figure. Figures 8 to 12 In one embodiment, the connection end 200 is provided with a cable board junction area 32, the snap-fit ​​structure 210 is located in the cable board junction area 32 and includes a pin 33, the free end of the pin 33 is provided with a 30°-45° oblique angle guide portion 34, and the side of the columnar section of the pin 33 is provided with a micro groove 35.

[0051] For example, the connection end 200 of this application is adapted to the row-spacing terminal 30, enabling the row-spacing terminal 30 to be connected to the circuit board, thereby realizing circuit connection. Specifically, a cable board interface 32 is provided in the connection end 200, and the snap-fit ​​structure 210 is located in the cable board interface 32. The core solution of the snap-fit ​​structure 210 is to use a cylindrical or square pin 33, which can be inserted into the corresponding metallized through hole of the PCB, thereby realizing circuit conduction between the connection terminal and the circuit board.

[0052] Furthermore, a 30°-45° angled guide 34 is provided at the free end of the pin 33, i.e., the tip of the pin 33. When the pin 33 is inserted into the PCB hole, the angled guide 34 can easily capture the edge of the hole opening, and even if there is a slight misalignment, it can slide into the hole through the angled surface. This significantly reduces the insertion force and prevents the pin 33 from bending or the PCB hole wall from being damaged due to forced insertion.

[0053] Furthermore, microgrooves 35 can be precisely machined onto the cylindrical surface of the pin 33. When the pin 33 is inserted into the PCB hole, molten solder will rise along the surface of the pin 33 during soldering. The microgrooves 35 provide a preset flow path for the liquid solder, guiding it to quickly and evenly fill the gap between the pin 33 and the hole wall. After the liquid solder cools and solidifies, it fills and solidifies within these microgrooves 35, effectively connecting the pin 33 to the hole from multiple angles, similar to several solder joints, thus greatly enhancing its pull-out and torsional resistance. Simultaneously, the microgrooves 35 can absorb and retain a larger amount of solder, ensuring a full solder joint while avoiding short circuits or solder balls that may be caused by disordered solder flow.

[0054] Please see Figures 1 to 12 In one embodiment, the thickness of the gold plating layer 400 is 0.5-2 μm, and a nickel underlayment 401 with a thickness of 1-3 μm is provided under the gold plating layer 400. The density of the gold plating layer 400 is ≥99.5%, and the porosity is ≤0.1 particles / mm². The thickness of the tin plating layer 410 is 5-15 μm, the purity of the tin layer is ≥99.9%, and the salt spray test tolerance time is ≥72 hours.

[0055] For example, before gold plating, a dense nickel underlayer 401 with a thickness of 1-3 μm is pre-plated onto the substrate. This nickel underlayer 401 acts as a barrier to prevent copper atoms from diffusing into the gold layer, thus avoiding the formation of a copper-gold diffusion layer. It also prevents external corrosive media from penetrating the copper substrate. Understandably, the high hardness of nickel provides a solid support for the upper gold plating layer 400.

[0056] Furthermore, a 0.5-2μm gold plating layer 400, made of hard gold such as cobalt alloy gold, is formed on the surface of the nickel underlayer 401. Specifically, the gold plating layer 400 has a density ≥99.5% and extremely low porosity, which can effectively isolate corrosive media such as oxygen and sulfides, thereby eliminating corrosion channels at the contact surface.

[0057] Furthermore, a 5-15μm matte tin layer 410 is applied to the connection end 200 and the transition area 300. The matte tin surface is granular, which is more conducive to the diffusion and bonding of tin atoms during soldering and crimping than bright tin. Understandably, the high-purity matte tin layer 410 can ensure excellent solderability and corrosion resistance, as well as a salt spray test time of ≥72 hours, ensuring the long-term reliability of the connection end 200.

[0058] Specifically, the dense, low-porosity gold plating layer 400 eliminates fretting and chemical corrosion paths at the contact surface, ensuring ultra-stable contact resistance throughout its entire lifespan. The nickel underlayer 401 acts as a transition layer, preventing copper diffusion and improving the overall bonding strength and hardness of the plating system, allowing the gold plating layer 400 to withstand repeated insertion and removal wear without exposing the base layer. By using selective gold plating—that is, using precious metals only in the most critical, performance-demanding contact areas, while using cost-effective matte tin in non-functional areas—a balance between performance and cost is achieved.

[0059] Please see Figure 5 and 12 In one embodiment, the connection between the connecting end 100 and the transition zone 300 is provided with a stress relief groove 310.

[0060] For example, one or more release grooves 310 of a specific shape are formed by stamping at the root of the resilient contact arm 110, i.e., at the part that connects with the thick transition zone 300. The groove can be U-shaped, V-shaped or semi-circular.

[0061] Furthermore, when the elastic contact arm 110 repeatedly bends and deforms during insertion and removal, its root will bear the greatest stress. The function of the release groove 310 is not to weaken the structure, but to actively redistribute and optimize the stress flow. By changing the geometry at this location, it eliminates sharp inner angles, allowing stress to transition smoothly and thus avoiding high stress concentration.

[0062] Please refer to 1 to Figure 13 Based on the stamped connecting terminal provided in the above embodiments, this application also provides a method for preparing the stamped connecting terminal provided in any of the above embodiments.

[0063] Specifically, the method provided in this application includes at least the following steps.

[0064] First, perform step S10 to pre-treat the high-precision phosphor bronze strip that meets the condition parameters, including degreasing with 5%-8% alkaline degreasing agent at 50-60℃ for 10-15 minutes, then removing rust with 10%-15% hydrochloric acid solution for 5-8 minutes, rinsing with pure water and drying.

[0065] For example, step S10 can thoroughly remove oil and oxide layers, preventing the subsequent electroplating layer from not bonding firmly to the substrate. At the same time, a clean surface can reduce wear and tear on the die during stamping and improve material flowability.

[0066] Then, step S20 is performed, using a continuous stamping die with an accuracy of ±0.005mm to sequentially punch, bend, and partially form the pretreated high-precision phosphor bronze, and obtain a stamped connection terminal including a contact end 100 and a connection end 200.

[0067] It is important to note that the blanking clearance of the continuous stamping die should be controlled at 0.01-0.02mm, and the bending radius should match the 300mm radius of the transition zone of the stamped connection terminal. This matching bending radius ensures smooth material deformation during bending, effectively preventing the generation of micro-cracks and uncontrolled springback, thus improving the structural integrity and dimensional stability of the terminal.

[0068] Furthermore, in step S30, a gold plating layer 400 is deposited on the contact end 100 of the stamped connection terminal at a current density of 1-3 A / dm² and an electroplating bath temperature of 40-50°C. This temperature and current density range can control the deposition rate of gold ions, promote fine grain growth, thereby forming a dense, low-porosity plating layer, resulting in a gold plating layer 400 with an adhesion strength ≥5 N / cm².

[0069] It should be noted that before gold plating the contact end 100, the process includes: activating the contact end 100 with a 5%-8% sulfuric acid solution to remove the extremely thin passivation film that may have formed on the surface of the contact end 100 after stamping, and reactivating it into a fresh metal surface. Simultaneously, a nickel underlayer 401 is prepared using a sulfate nickel plating process.

[0070] Specifically, when preparing the nickel undercoat 401, the electroplating solution is a nickel sulfate solution with the following parameters: nickel sulfate 200-250 g / L, nickel chloride 30-40 g / L, and boric acid 30-40 g / L. The pH of the electroplating solution is controlled at 3.5-4.5, the electroplating temperature is 50-55℃, the current density is 2-4 A / dm², and the electroplating time is 3-6 min, forming a nickel layer with a thickness of 1-3 μm.

[0071] Furthermore, in step S40, a tin plating layer 410 is plated onto the connection end 200 and transition area 300 of the stamped connection terminal at a current density of 1-2 A / dm² and an electroplating solution temperature of 25-35°C.

[0072] Step S40 provides protection and processability for the soldering and crimping areas. The aforementioned process conditions facilitate the formation of a granular, matte tin plating layer with improved solderability and resistance to tin whiskers. Simultaneously, the moderately thick matte tin layer 410 provides an effective anti-oxidation and anti-corrosion barrier for the copper substrate, with a salt spray test capability of ≥72 hours, sufficient to meet most stringent environmental requirements.

[0073] Finally, perform step S50, after electroplating, rinse with pure water and dry at 80-100℃ for 5-10 minutes.

[0074] Specifically, after electroplating, the stamped connectors undergo multiple counter-current rinsings with pure water to thoroughly remove any residual electroplating solution from the surface. They are then dried in hot air at 80-100℃ for 5-10 minutes. This temperature and time are sufficient to evaporate moisture but are below the recrystallization temperature of tin, thus avoiding any adverse effects on the plating structure. Therefore, the stamped connectors can be thoroughly cleaned and quickly dried, preventing the formation of residual electroplating salts and watermarks, and preventing subsequent corrosion caused by moisture absorption from residues on the surface of the stamped connectors.

[0075] In summary, this application provides a stamped connecting terminal and its manufacturing method. The integrated molding process avoids the gaps caused by separate assembly of the stamped connecting terminal. Combined with the gradient contact protrusions 122 of the elastic contact arm 110, progressive contact pressure is formed, ensuring a tight fit between the mating parts and reducing contact gaps and the risk of loosening. The obliquely interlaced anti-slip teeth 211 form a multi-dimensional interlocking structure, thereby improving locking force and effectively resisting loosening under pulling and vibration conditions. Simultaneously, the force is distributed to prevent tooth tip deformation, ensuring long-term stable connection. The gradient contact protrusions 122 and the elastic contact arm 110 work together to automatically compensate for minor dimensional deviations in the mating parts. Even if some contact protrusions 122 wear slightly, the higher-height contact protrusions 122 can still maintain effective contact, adapting to high-frequency insertion and removal scenarios. The structure combined with the guide flange 120 enables automatic alignment of the mating parts, reducing the difficulty of initial alignment during insertion and removal, reducing insertion force, and avoiding structural damage caused by forced mis-insertion.

[0076] Leveraging the excellent conductivity of high-precision phosphor bronze strips, combined with a densely plated gold layer 400 on the contact terminals 100, contact resistance is significantly reduced, minimizing current transmission losses. Simultaneously, the ratio of phosphorus to high-purity copper ensures minimal fluctuations in contact resistance across a wide temperature range of -40℃ to 125℃, making it suitable for use in extreme environments. Furthermore, a nickel undercoat 401 prevents copper-gold diffusion, enhances the adhesion of the gold plating layer 400, and results in low plating peeling after high and low temperature cycling, preventing conductivity degradation caused by oxidation and sulfidation. By using localized gold plating—that is, using precious metals only in the most critical and performance-required contact areas, while using cost-effective matte tin plating in non-functional areas—a balance between performance and cost is achieved.

[0077] In the description herein, it should be understood that the terms "upper," "lower," "left," "right," and other orientations or positional relationships are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used merely for descriptive distinction and have no special meaning.

[0078] In the description of this specification, references to terms such as "an embodiment," "example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0079] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0080] The technical principles of this application have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of this application and should not be construed as limiting the scope of protection of this application in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of this application without inventive effort, and these embodiments will all fall within the scope of protection of this application.

Claims

1. A stamped connecting terminal, integrally formed from high-precision phosphor bronze strip through continuous stamping, characterized in that, include: The contact end (100) is used to make an electrical connection with the adapter connector, including a pair of oppositely arranged elastic contact arms (110). The free end of the elastic contact arm (110) is bent to form a guide flange (120) with a guide surface (121). A plurality of hemispherical contact protrusions (122) are provided at the junction of the guide surface (121) and the elastic contact arm (110). Each of the contact protrusions (122) is arranged along the insertion and extraction direction, and the center distance between adjacent contact protrusions (122) is 0.3-0.5mm. The height increases by 0.02-0.03mm from the insertion and extraction inlet to the inside. The connecting end (200) is used to fix the connection to the cable or circuit board. The connecting end (200) is provided with a snap-fit ​​structure (210). The snap-fit ​​structure (210) is provided with at least two rows of staggered anti-slip teeth (211). And a transition region (300) located between the contact end (100) and the connection end (200), wherein the cross-sectional area of ​​the transition region (300) is greater than the cross-sectional area of ​​the contact end (100) and the connection end (200); The contact end (100) has a gold plating layer (400) on its surface, and the connection end (200) and the transition area (300) have a matte tin plating layer (410) on their surfaces; and The high-precision phosphorus copper strip has a purity of ≥99.95%, a phosphorus content of 0.03-0.08wt%, a tensile strength of 350-400MPa, and an elongation of ≥15%.

2. The stamped connecting terminal according to claim 1, characterized in that, The stamped connection terminal is a socket terminal (10). The contact end (100) of the socket terminal (10) is a socket structure constructed by two symmetrically arranged elastic contact arms (110). The inner surface of the two elastic contact arms (110) is fully covered by the gold plating layer (400), and the free end of the elastic contact arm (110) is an outwardly turned guide flange (120) forming a flared structure (11).

3. The stamped connecting terminal according to claim 1, characterized in that, The stamped connection terminal is a pin terminal (20). The contact end (100) of the pin terminal (20) is a pin structure constructed by two symmetrically arranged elastic contact arms (110). The outer surface of the elastic contact arm (110) is covered with the gold plating layer (400), and the free end of the elastic contact arm (110) is an inwardly turned guide flange (120) forming a closed structure (21).

4. The stamped connecting terminal according to claim 2 or 3, characterized in that, The connecting end (200) is provided with a cable riveting area (12) for riveting with a cable, and the snap-fit ​​structure (210) is located in the cable riveting area (12). The snap-fit ​​structure (210) includes a crimping groove (13), and a first crimping plate (14) and a second crimping plate (15) are respectively provided on the side of the crimping groove (13); and The anti-slip teeth (211) are disposed on the surface of the bottom of the first pressing plate (14), the second pressing plate (15) or the pressing groove (13) and are distributed in an oblique staggered manner.

5. The stamped connecting terminal according to claim 1, characterized in that, The stamped connection terminal is a row spacing terminal (30), and the contact end (100) of the row spacing terminal (30) is a pair of elastic contact arms (110) facing each other, and a clamping gap (31) is formed between the two elastic contact arms (110) spring pieces.

6. The stamped connecting terminal according to claim 5, characterized in that, The connection end (200) is provided with a cable board receiving area (32), and the snap-fit ​​structure (210) is located in the cable board receiving area (32). The snap-fit ​​structure (210) includes a pin (33), the free end of which is provided with a 30°-45° angled guide portion (34); and the side of the columnar section of the pin (33) is provided with a micro-groove (35).

7. The stamped connecting terminal according to claim 1, characterized in that, The thickness of the gold plating layer (400) is 0.5-2μm, and a nickel underlay layer (401) with a thickness of 1-3μm is provided under the gold plating layer (400). The gold plating layer (400) has a density ≥99.5% and a porosity ≤0.1 cells / mm²; and The thickness of the matte tin layer (410) is 5-15 μm, and the purity of the tin layer is ≥99.9%.

8. The stamped connecting terminal according to claim 1, characterized in that, The connection between the connecting end (100) and the transition zone (300) is provided with a stress relief groove (310).

9. A method for preparing a stamped connecting terminal according to any one of claims 1 to 8, characterized in that, include: Step S10: Pre-treat the high-precision phosphor bronze strip that meets the condition parameters, including: degreasing with 5%-8% alkaline degreasing agent at 50-60℃ for 10-15 minutes, removing rust with 10%-15% hydrochloric acid solution for 5-8 minutes, rinsing with pure water and drying. Step S20: Using a continuous stamping die with an accuracy of ±0.005mm, the pre-treated high-precision phosphor bronze is sequentially punched, bent and partially formed to obtain a stamped connection terminal including a contact end (100) and a connection end (200). Step S30: A gold plating layer (400) is plated onto the contact end (100) of the stamped connection terminal under the conditions of a current density of 1-3 A / dm² and an electroplating solution temperature of 40-50°C. Step S40: The connecting end (200) and transition area (300) of the stamped connecting terminal are plated with a mist tin layer (410) under the conditions of current density of 1-2A / dm² and electroplating solution temperature of 25-35℃. Step S50: After electroplating, rinse with pure water and dry at 80-100℃ for 5-10 minutes.

10. The method for preparing a stamped connecting terminal according to claim 9, characterized in that, In step S20, the blanking clearance of the continuous stamping die is controlled to be 0.01-0.02 mm, and the bending radius matches the radius of the transition area (300) of the stamping connection terminal; and In step S30, before gold plating the contact end (100), the process further includes: activating the contact end (100) with a 5%-8% sulfuric acid solution, and first preparing a nickel underlayer (401) using a sulfate nickel plating process.

Images