A double crown spring for a high current connector and a method of manufacturing the same

Abstract

This invention relates to a double-layer crown spring adapted for high-current connectors and its manufacturing method. The double-layer crown spring includes a cantilever terminal and a simply supported terminal arranged coaxially. This double-layer crown spring, through a double-layer staggered spring structure, achieves multi-point contact within a complete circle, significantly reducing temperature rise under high-current conditions, and providing a smooth insertion and removal feel without jamming or arcing. The manufacturing method includes the following steps: blank preparation, overlapping and riveting, blank rounding, and blank forming. This method, through a continuous manufacturing process of separate forming and overlapping of two strips, achieves high product consistency, significantly improves yield, and more than doubles production efficiency compared to traditional separate assembly processes. It can be mass-produced to meet the assembly and usage needs of various high-current connector products.

Description

Technical Field

[0001] This invention relates to the field of electrical connector technology, and in particular to a double-layer crown spring adapted for high-current connectors and its manufacturing method. Background Technology

[0002] A crown spring is a one-piece ring-shaped connector resembling a crown, possessing both electrical conductivity and mechanical elastic clamping capabilities. It typically features dozens of independent springs in a ring simultaneously engaging with the male pin, distributing the total current across multiple conductive channels. This significantly reduces the current-carrying load of a single spring, resulting in less Joule heating and lower temperature rise under high current, making it suitable for high-power current-carrying scenarios. After the springs expand, they continuously press the male pin inward, and the stable positive force can pierce the oxide layer on the conductor surface, maintaining low and uniform contact resistance over a long period, avoiding problems such as single-point heating, arcing, and excessive voltage drop. The symmetrical ring structure ensures contact points around the pin's 360° circumference, preventing one-sided poor contact and localized conductivity issues, and improving conductivity continuity under vibration conditions. When the pin is inserted, the springs expand outward, relying on the torsional cantilever rebound to generate a constant radial positive force, firmly holding the pin and resisting gaps caused by equipment vibration and impact, preventing momentary power outages.

[0003] Chinese patent CN120728280A discloses a conductive terminal structure and socket. This conductive terminal structure is similar to a cylindrical structure, with spring contacts extending from the support parts on both sides towards the middle, forming an interlocking conductive contact structure. This structure provides a relatively limited spring contact length, and the two support parts (two circular structures) are only connected by two connecting ribs on the edge. Under stress, the center of the circular rings cannot effectively maintain a coaxial relationship, and good circular contact cannot be guaranteed after insertion, resulting in unreliable current carrying capacity.

[0004] Chinese patent CN113540855A discloses a resilient terminal, a method for manufacturing a resilient terminal, an electrical connector, and an electronic device. This resilient terminal has a cylindrical shape, with the spring simultaneously serving as both a conductive and structural connection, thus ensuring circular contact compared to the aforementioned patents. The resilient terminal is formed by cutting a rectangular blank and then enclosing it, requiring a certain width of slits between adjacent springs to form cantilever structures. Limited by the punch strength, there is a minimum limit to the width of this slit; the smaller the terminal diameter, the larger the proportion of width occupied by the slit, resulting in a significant reduction in contact density, making it unsuitable for use in high-current connectors. Furthermore, with the ends of the resilient terminal constrained, the middle of the spring exerts a large force during insertion and removal, making insertion and removal less smooth.

[0005] Therefore, it is necessary to design a new crown spring structure and manufacturing method to solve the above problems. Summary of the Invention

[0006] The main objective of this invention is to provide a double-layer crown spring adapted to high-current connectors. During insertion, the two types of spring contacts are nearly circularly aligned, resulting in a large number of contact points. Insertion and removal are very smooth. When engaging with pins, the continuously increasing staggered contact points reduce the arc and voltage drop generated by point contact. The entire structure is stable and flexible, with very low dynamic contact resistance and low temperature rise, making it more suitable for high-current products.

[0007] The present invention achieves the above-mentioned objective through the following technical solution: a double-layer crown spring adapted to a high-current connector, comprising a cantilever terminal and a simply supported terminal coaxially nested together. The cantilever terminal includes a first support ring and a plurality of cantilever spring pieces evenly distributed around the first axial side of the first support ring. The simply supported terminal has an integral squirrel cage structure, including a second support ring, a third support ring located on the first axial side of the second support ring, and a plurality of bridge spring pieces evenly distributed around the axis and connected between the second support ring and the third support ring. The first support ring is tightly fixed to the inner wall of the second support ring. The cantilever spring pieces and the bridge spring pieces are interleaved and distributed alternately, and the middle of both are recessed inward.

[0008] Specifically, the first support ring has several hooks evenly distributed around the second axial side, the first axial side is opposite to the second axial side, and the ends of the hooks hook up towards the first axial side. The second support ring is provided with several holes that are adapted to each hook.

[0009] Furthermore, the width of the card hole is 5-15% larger than the width of the card hook.

[0010] Specifically, the concave parts of all cantilever springs are located in the same axial position, and the concave parts of all bridge springs are located in the same axial position, but the concave parts of the cantilever springs and the concave parts of the bridge springs are located in different axial positions.

[0011] Furthermore, all cantilever springs have a reinforcing bulge that bulges outward in the radial direction at their concave portions, and the bridge springs have a second reinforcing bulge that bulges outward in the radial direction at their concave portions.

[0012] Specifically, each cantilever spring and each bridge spring is twisted into a spiral structure in the same direction of rotation.

[0013] Another major objective of this invention is to provide a manufacturing method for the aforementioned double-layer crown spring, which can use two strips to first form blanks separately, and then stack and wrap them together, thereby continuously completing the manufacturing of the double-layer crown spring with high production efficiency.

[0014] This invention achieves the above objective through the following technical solution: a method for manufacturing a double-layer crown spring, comprising the following steps: S1. Blank preparation: Prepare a first strip and a second strip. The first strip includes an integrally connected first continuous material and a first blank corresponding to the cantilever terminal. The first continuous material has a first positioning hole. The first continuous material is connected to the middle of the first blank by two symmetrically arranged first connecting strips. The second strip includes an integrally connected second continuous material and a second blank corresponding to the simply supported terminal. The second continuous material has a second positioning hole. The second continuous material is connected to the middle of the second blank by a centrally arranged second connecting strip. The first positioning hole and the second positioning hole have the same diameter and the same pitch. S2, Overlapping and riveting: The first strip and the second strip are aligned and overlapped using the correspondence between the first positioning hole and the second positioning hole, and the first blank and the second blank are directly fixed into a blank composite body. The positions of the two first connecting strips and the second connecting strip are staggered. The two first connecting strips are cut off, and the first continuous material is removed, so that the blank composite body is connected to the second continuous material only by the first connecting strip. S3, Blank Encirclement: Using the second positioning hole as the positioning reference, the blank stack is deformed into an encirclement shape with the second blank on the outside and the first blank inside, so that the blank stack is deformed into the double-layer crown spring in steps. S4. Blanking and forming: Using the second positioning hole as the positioning reference, cut off the connection between the second connecting strip and the double-layer crown spring, so that the double-layer crown spring is blanked and formed.

[0015] Specifically, the second continuous material has a frame-shaped structure that completely surrounds the second blank, and the second continuous material has auxiliary positioning holes with synchronous distances machined on another strip area opposite to the strip area where the second positioning hole is located.

[0016] Specifically, the first blank has a comb-shaped structure, including a first strip portion, a plurality of cantilever spring pieces equidistantly arranged on a first side of the first strip portion, and a plurality of L-shaped riveting pieces equidistantly arranged on a second side of the first strip portion. The L-shaped riveting pieces are vertically connected to the first strip portion, and the first connecting strip connects the middle of the second side of the first strip portion to the first continuous material. The second blank has a grid structure, including a second strip portion, a third strip portion parallel to the second strip portion, and a plurality of bridge-type spring pieces equidistantly connecting the second strip portion and the third strip portion. The second strip portion is provided with a locking hole matching the position of the L-shaped riveting piece. In the overlapping riveting step, the end of the L-shaped riveting piece is inserted into the locking hole, and then the L-shaped riveting piece is riveted to form a hook that hooks the locking hole. The first strip portion encloses to form the first support ring, the second strip portion encloses to form the second support ring, and the third strip portion encloses to form the third support ring.

[0017] Furthermore, during the blank preparation process, the initial lengths of the second strip and the third strip are equal to the length of the first strip. While keeping the length of the bridge spring constant, the second strip and the third strip are extended synchronously by 5-15% through rolling.

[0018] Furthermore, a torsion processing step is provided between the overlapping and riveting step and the blank rounding step: while keeping the second strip portion parallel to the third strip portion, the second strip portion is fixed and the third strip portion is pulled off-center along the conveying direction of the material strip, so that the bridge spring and the cantilever spring are tilted in the same direction.

[0019] The beneficial effects of the technical solution of this invention are: 1. The double-layer crown spring prepared in this embodiment achieves full-circle multi-contact contact through the double-layer staggered spring sheet structure of cantilever terminal and simple support terminal, which greatly reduces the temperature rise under high current conditions, and provides a smooth insertion and removal feel without jamming or arcing. 2. Through the continuous manufacturing process of split molding and overlapping of two strips, the product molding consistency is high and the yield rate is greatly improved. The production efficiency is more than doubled compared with the traditional split assembly process, and it can be batch adapted to the assembly and use needs of various high current connector products. Attached Figure Description

[0020] Figure 1 This is a three-dimensional diagram of a double-layered crown spring; Figure 2 An exploded view of a double-layered crown spring; Figure 3 This is a top-view diagram showing the changes in the strip's condition from billet preparation to twisting. Figure 4 This is a diagram showing the change in the state of the strip material from the rounding of the billet to the blanking and forming process. Figure 5 The temperature rise diagram of a double-layer crown spring under a current of 200A is shown. Figure 6 The temperature rise diagram of a double-layer crown spring under a current of 300A is shown. Figure 7 Force-time test curves for a single bridge-type spring and a single cantilever spring; Figure 8 This is a diagram showing the insertion and extraction force test of a double-layer crown spring.

[0021] The numbers in the image represent: 1-Double-layer crown spring, 11-Cantilever terminal, 111-First support ring, 112-Cantilever spring, 1121-Reinforcing protrusion, 113-Hook, 12-Simple support terminal, 121-Second support ring, 1211-Hook hole, 122-Third support ring, 123-Bridge spring; 2-First strip, 21-First continuous strip, 211-First positioning hole, 22-First blank, 221-First strip section, 222-L-shaped riveting piece, 23-First connecting strip; 3-Second strip, 31-Second continuous strip, 311-Second positioning hole, 312-Auxiliary positioning hole, 32-Second blank, 321-Second strip section, 322-Third strip section, 33-Second connecting strip; 4-Burnt composite. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to specific embodiments.

[0023] Example: I. Specific Structure of Double-Layer Crown Spring like Figure 1 As shown, this embodiment discloses a double-layer crown spring 1 adapted to high-current connectors. The whole adopts an inner and outer double-layer coaxial nested structure. The core is composed of a cantilever terminal 11 and a simple branch terminal 12 arranged coaxially. Through the structure of double-layer springs interlocking, it achieves high-current adaptation performance with multiple contact points, low resistance, and low temperature rise. It effectively solves the problems of traditional single-layer crown springs with few contacts, large arc, high voltage drop, and poor stability when adapting to high-current conditions.

[0024] like Figure 2 As shown, the cantilever terminal 11 includes a first support ring 111 and a plurality of cantilever spring pieces 112 evenly distributed around the first axial side of the first support ring 111. All the cantilever spring pieces 112 are arranged in a ring array with the first support ring 111 as the reference to ensure uniformity of force and contact. The simply supported terminal 12 is an integral squirrel cage structure, specifically including a second support ring 121, a third support ring 122 located on the first axial side of the second support ring 121, and a plurality of bridge spring pieces 123. The third support ring 122 is axially parallel to the second support ring 121 and spaced apart. The plurality of bridge spring pieces 123 are evenly distributed around the axis, and their two ends are fixedly connected to the second support ring 121 and the third support ring 122 respectively, forming an overall stable cage support structure.

[0025] In the assembled state, the first support ring 111 of the cantilever terminal 11 is tightly fixed to the inner wall of the second support ring 121 of the simply supported terminal 12, achieving coaxial positioning and fixation of the inner and outer terminals. At the same time, the cantilever spring 112 and the bridge spring 123 are arranged in an interleaved distribution pattern, without overlap or gap compression, and the middle of both types of springs is recessed inward to form a contact protrusion structure facing the pin.

[0026] To achieve precise locking and fixing of the cantilever terminal 11 and the simply supported terminal 12, a plurality of hooks 113 are evenly arranged around the second axial side of the first support ring 111. The first axial side and the second axial side are two opposite axial directions, and the ends of the hooks 113 hook upwards towards the first axial side, forming an inverted locking structure. Correspondingly, a plurality of locking holes 1211 are provided on the second support ring 121, which correspond one-to-one with the hooks 113. The hooks 113 can be inserted into the locking holes 1211 to achieve the limiting and fixing of the two layers of terminals. In this embodiment, the width of the locking hole 1211 is 5-15% larger than the width of the hook 113. This size gap design can ensure that the hooks 113 can be smoothly inserted into the assembly, avoiding structural deformation and assembly jamming caused by interference fit, and can also prevent the coaxiality of the two layers of terminals from being misaligned and loosening due to excessive gap, thus ensuring the assembly accuracy and operational stability of the overall structure.

[0027] To further optimize contact performance and deformation adaptability, this embodiment employs a differentiated design for the concave positions of the two types of spring contacts: the concave portions of all cantilever spring contacts 112 are located in the same axial position, as are the concave portions of all bridge spring contacts 123, and the axial positions of the concave portions of the cantilever spring contacts 112 and the bridge spring contacts 123 are staggered. This staggered structure design allows the contact points of the double-layer spring contacts to engage in a step-by-step manner along the axial direction during pin insertion, progressively distributing contact stress and avoiding spring contact fatigue and deformation failure caused by concentrated force at the same axial position. Simultaneously, it further increases the number of dynamic contact points, continuously optimizing the low-resistance and low-arc operating characteristics.

[0028] To enhance the structural strength and fatigue resistance of the spring and prevent deformation and loosening under conditions of repeated insertion and removal and high current heating, a reinforcing bulge 1121 is provided at the concave part of the cantilever spring 112, bulging radially outward. The reinforcing bulge 1121 effectively improves the structural stiffness of the bending deformation position of the cantilever spring 112, disperses deformation stress, and improves the spring's rebound consistency and service life. At the same time, it does not affect the contact accuracy between the inner side of the spring and the pin, ensuring the stability of contact resistance and temperature rise indicators during long-term use.

[0029] like Figure 5 and Figure 6As shown, the socket base is made of T2 copper (100% conductivity), and the double-layer crown spring 1 is made of beryllium copper (only 60% conductivity). The crown spring itself has weaker conductivity than the base and is the core area for heat generation. The structure adopts a double-row contact point design, with multiple contact points for current diversion, reducing the current load on a single spring and suppressing temperature rise structurally.

[0030] like Figure 7 As shown, the bridge spring 123 has a positive force of 2.27N, which is within the ideal range for low-current signal connectors. It can stably control contact resistance and resist minor vibrations. The cantilever spring 112 has a positive force of 4.31N, which meets the requirements for high-current conduction and clamping. Its current carrying capacity and heat generation control capabilities meet the standards. The layered force design of the wide and narrow pins is suitable for their respective functions, and the force curves all have stable and flat platforms. After mating, the elastic clamping force is stable, and the static contact reliability is guaranteed.

[0031] like Figure 8 As shown, the insertion direction is from the root of the cantilever spring 112 towards the end. The total insertion force is 32.03N, and the total extraction force is 14.95N. The extraction force is 46.7% of the insertion force, which is within the excellent range of 40% to 60%. This design prevents accidental loosening of the connector under impact and vibration conditions, and also avoids excessive resistance during disassembly. During insertion, the cantilever spring 112 and the bridge spring 123 can form a near-circular butt contact effect, significantly increasing the number of contact points. The double-layer springs undergo synchronous flexible deformation during insertion and removal, making the insertion and removal operation smoother and more seamless. At the same time, as the insertion depth of the pin gradually increases, the number of staggered contact points of the two types of springs continues to increase, which can effectively disperse the single-point contact pressure, avoid the arcing phenomenon caused by traditional single-point or few-point contact, and reduce the contact voltage drop, significantly reducing dynamic contact resistance and operating temperature rise. This design is perfectly suited for the long-term operating conditions of high-current connectors, and the overall structure combines stability and elastic deformation capability.

[0032] Furthermore, each cantilever spring 112 and each bridge spring 123 is twisted in the same direction of rotation to form a helical structure. This helical spring structure allows for an arc-shaped surface contact between the spring and the pin, replacing traditional line or point contact, further increasing the contact area. Simultaneously, it makes the deformation process of the spring smoother and more uniform, resulting in stable and gentle insertion and extraction damping. This completely solves the problems of jamming and severe contact wear associated with traditional crown springs, further reducing dynamic contact resistance and adapting to ultra-high current transmission requirements. With the same axial length of the crown spring, the torsion structure increases the actual length of each spring, increasing the yield margin.

[0033] II. Detailed Introduction to the Manufacturing Method of Double-Layer Crown Springs This embodiment discloses a continuous manufacturing method for the above-mentioned high-current adapter double-layer crown spring 1. It adopts an integrated process of dual-material strip split molding, stacking and assembly, overall rounding, and precise blanking molding, which can realize automated continuous production, greatly improve production efficiency and product consistency. The specific preparation steps are as follows: S1. Billet preparation like Figure 3 As shown, a first strip 2 and a second strip 3 that are pre-prepared to match each other are provided. The two types of strips have the same pitch and positioning hole diameter, which is suitable for automated production line operations. The first strip 2 consists of a first continuous material 21 integrally connected to a first blank 22 corresponding to the cantilever terminal 11. The first continuous material 21 has first positioning holes 211 uniformly machined on it, which serve as positioning references for the entire assembly and forming process. The first continuous material 21 is connected to the middle of the first blank 22 by two symmetrically arranged first connecting strips 23, which ensures the balanced force during the blank forming process.

[0034] The first blank 22 has a comb-shaped structure, including a first strip 221, several cantilever springs 112 and several L-shaped rivet pieces 222. Several cantilever springs 112 are equidistantly arranged on the first side of the first strip 221, and several L-shaped rivet pieces 222 are equidistantly arranged on the second side of the first strip 221. The L-shaped rivet pieces 222 are perpendicularly connected to the first strip 221, and two first connecting strips 23 are symmetrically connected at the middle position of the second side of the first strip 221.

[0035] The second strip 3 consists of a second continuous strip 31 integrally connected with a second blank 32 corresponding to a simply supported terminal 12. The second continuous strip 31 is a frame-shaped structure that completely surrounds the second blank 32, resulting in stronger structural stability. A second positioning hole 311 is machined on the second continuous strip 31, with the same diameter and pitch as the first positioning hole 211, ensuring precise alignment of the two strips. The second continuous strip 31 is connected to the center of the second blank 32 via a centrally located second connecting strip 33, ensuring the center positioning accuracy of the second blank 32 during forming and stacking. Simultaneously, the second continuous strip 31 has auxiliary positioning holes 312 with a synchronous pitch machined on the opposite side of the strip area containing the second positioning hole 311, further improving the positioning accuracy of subsequent rounding and blanking forming processes.

[0036] The second blank 32 is a grid-type integrated structure, including a second strip portion 321, a third strip portion 322, and several bridge-type spring pieces 123. The second strip portion 321 and the third strip portion 322 are parallel to each other, and the several bridge-type spring pieces 123 are equidistantly connected between the two strip portions to form a hollow grid structure. Among them, the second strip portion 321 has a locking hole 1211 that matches the position of the L-shaped riveting piece 222.

[0037] In this step, initially, the lengths of the second strip portion 321 and the third strip portion 322 are exactly the same as the length of the first strip portion 221. This allows the cantilever spring piece 112 and the bridge spring piece 123 to be viewed as equidistantly intersecting during the blank stacking process. However, after rounding, the second support ring 121 formed by the second strip portion 321 has a longer circumference than the first support ring 111 formed by the first strip portion 221. To adapt to the subsequent rounding forming dimensions and ensure coaxial matching of the double-layer structure, while keeping the length of the bridge spring piece 123 unchanged, the second strip portion 321 and the third strip portion 322 are simultaneously extended by 5-15% through a precision rolling process. This compensates for the circumference error after rounding, ensuring the dimensional compatibility of the second support ring 121, the third support ring 122, and the first support ring 111 after forming. When the first strip 221 and the drawn second strip 321 are in a planar state, all L-shaped rivet pieces 222 must be able to be inserted normally into their corresponding locking holes 1211. Under this premise, the L-shaped rivet pieces 222 can only play an anchoring role after they are subsequently deformed into hooks 113. Therefore, the width of the locking hole 1211 must be 5 to 15% larger than the width of the hook 1211 (i.e. the width of the L-shaped rivet pieces 222) so as to provide adaptive adjustment space for all L-shaped rivet pieces 222 to be in place.

[0038] S2, Overlap riveting like Figure 3 As shown, using the first positioning hole 211 and the second positioning hole 311 as precise alignment references, the first material strip 2 and the second material strip 3 are precisely overlapped, so that the first blank 22 is attached to the inner side of the second blank 32. During the overlap process, the end of the L-shaped riveting piece 222 of the first blank 22 is inserted into the corresponding locking hole 1211 of the second blank 32. Then, the L-shaped riveting piece 222 is bent and deformed by the riveting equipment, so that the L-shaped riveting piece 222 bends and hooks onto the locking hole 1211, forming an integrated locking structure of hook 113, thereby fixing the first blank 22 and the second blank 32 and forming an integral blank stack 4.

[0039] Because a rounding operation is required later, the fewer connection points between the billet stack 4 and the second continuous material 31, the better. Therefore, only one centrally located second connecting strip 33 was designed during billet preparation, allowing the billet stack 4 to round from both sides towards the center. However, if the position of the first connecting strip 23 coincides with the second connecting strip 33, it will interfere with the operation of disconnecting the first connecting material 21 from the first billet 22. Therefore, to balance the operability of the process and the stability of the connection between the first billet 22 and the first continuous material 21, the connection points between the first continuous material 21 and the first billet 22 need to be symmetrical (i.e., two first connecting strips 23). In the stacked state, the two symmetrically located first connecting strips 23 and the centrally located second connecting strip 33 are staggered, with no structural interference. After the stacking and fixing are completed, the two first connecting strips 23 can be cut off by a cutting device, thereby removing the first continuous material 21. This ensures that the formed billet stack 4 is connected to the second continuous material 31 only through the second connecting strip 33, preserving the connection reference for subsequent forming and conveying, and simplifying the subsequent process flow.

[0040] S3, Torsion Treatment like Figure 3 As shown, while keeping the second strip section 321 and the third strip section 322 parallel to each other throughout the process, the second strip section 321 is fixed, and the third strip section 322 is slightly pulled off course along the conveying direction of the material belt by the traction device, so that the bridge spring sheet 123 tilts in the same direction as a whole; at the same time, relying on the fixed structure of the double-layer blank, the inner cantilever spring sheet 112 is driven to tilt synchronously in the same direction, so that all cantilever spring sheets 112 and bridge spring sheets 123 tilt in the same direction of rotation, laying the foundation for the subsequent spiral structure forming, ensuring that all spring sheets have the same torsion angle and high structural uniformity.

[0041] S4, Blank rounding like Figure 4As shown, using the second positioning hole 311 and the auxiliary positioning hole 312 as positioning references, a step-by-step progressive rounding process is adopted to bend and shape the blank stack 4, always maintaining a double-layer nested state with the second blank 32 on the outside and the first blank 22 inside. Through multiple progressive bending and rounding processes, the strip-shaped blank stack 4 is gradually deformed into a ring structure. The progressive bending method is to first bend both sides of the blank stack 4 into 90° arcs, and then, with the core-pulling structure, bend the middle plane into a 180° arc, thus forming a 360° circular structure. Finally, the first strip portion 221 is formed into a round shape to become the first support ring 111, the second strip portion 321 is formed into a round shape to become the second support ring 121, and the third strip portion 322 is formed into a round shape to become the third support ring 122. Combined with the spring structure that has undergone the previous torsion treatment, a double-layer crown spring 1 is finally formed, in which the cantilever spring 112 and the bridge spring 123 are distributed alternately and twisted in a spiral. However, it is still connected to the second continuous material 31 by the second connecting strip 33. The step-by-step rounding process can effectively avoid the problems of spring deformation, cracking, and angle displacement caused by excessive stress in a single molding.

[0042] S5, Blanking and Forming like Figure 4 As shown, the second positioning hole 311 is used as the positioning reference throughout the process to ensure that the blanking and forming position is accurate and without deviation. The connecting structure between the second connecting strip 33 and the main body of the double-layer crown spring 1 is precisely cut by the cutting mold, so that the formed double-layer crown spring 1 is completely separated from the second continuous material 31, completing the automated blanking and forming, and finally obtaining the finished product of the high-current adapter double-layer crown spring 1 with complete structure, uniform size and stable performance.

[0043] III. Implementation Results Description The double-layer crown spring 1 prepared in this embodiment achieves full-circle multi-contact contact through the double-layer staggered spring sheet structure of cantilever terminal 11 and simple branch terminal 12, which greatly reduces the temperature rise under high current conditions, and provides a smooth insertion and removal feel without jamming or arcing. At the same time, through the continuous manufacturing process of double-material strip split molding and overlapping rounding, the product molding consistency is high, the yield rate is greatly improved, and the production efficiency is more than doubled compared with the traditional split assembly process. It can be mass-produced to meet the assembly and use needs of various high-current connector products.

[0044] The above descriptions are merely some embodiments of the present invention. Those skilled in the art can make various modifications and improvements without departing from the inventive concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A double crown spring for a high current connector, characterized by: The device includes cantilever terminals and simply supported terminals arranged coaxially. The cantilever terminal includes a first support ring and a plurality of cantilever spring pieces evenly distributed around the first axial side of the first support ring. The simply supported terminal has an integral squirrel cage structure, including a second support ring, a third support ring located on the first axial side of the second support ring, and a plurality of bridge spring pieces evenly distributed around the axis and connected between the second support ring and the third support ring. The first support ring is tightly fixed to the inner wall of the second support ring. The cantilever spring pieces and the bridge spring pieces are interleaved and distributed at intervals, and the middle of both are recessed inward.

2. The double-layer crown spring according to claim 1, characterized in that: The first support ring has several hooks evenly distributed around the second axial side. The first axial side is opposite to the second axial side. The ends of the hooks hook up towards the first axial side. The second support ring has several holes that are adapted to each hook.

3. The double-layer crown spring according to claim 2, characterized in that: The width of the card hole is 5-15% larger than the width of the hook.

4. The double-layer crown spring according to claim 1, characterized in that: The concave portions of all cantilever springs are located in the same axial position, and the concave portions of all bridge springs are located in the same axial position. However, the concave portions of the cantilever springs and the concave portions of the bridge springs are located in different axial positions.

5. The double-layer crown spring according to claim 4, characterized in that: All cantilever springs have a reinforcing bulge that bulges outward in the concave part, and the bridge springs have a second reinforcing bulge that bulges outward in the concave part.

6. The double-layer crown spring according to claim 1, characterized in that: Each cantilever spring and each bridge spring is twisted into a spiral structure in the same direction of rotation.

7. A method for manufacturing a double-layer crown spring according to any one of claims 1 to 6, characterized in that the step include: S1. Blank preparation: Prepare a first strip and a second strip. The first strip includes an integrally connected first continuous material and a first blank corresponding to the cantilever terminal. The first continuous material has a first positioning hole. The first continuous material is connected to the middle of the first blank by two symmetrically arranged first connecting strips. The second strip includes an integrally connected second continuous material and a second blank corresponding to the simply supported terminal. The second continuous material has a second positioning hole. The second continuous material is connected to the middle of the second blank by a centrally arranged second connecting strip. The first positioning hole and the second positioning hole have the same diameter and the same pitch. S2, Overlapping and riveting: The first strip and the second strip are aligned and overlapped using the correspondence between the first positioning hole and the second positioning hole, and the first blank and the second blank are directly fixed into a blank composite body. The positions of the two first connecting strips and the second connecting strip are staggered. The two first connecting strips are cut off, and the first continuous material is removed, so that the blank composite body is connected to the second continuous material only by the first connecting strip. S3, Blank Encirclement: Using the second positioning hole as the positioning reference, the blank stack is deformed into an encirclement shape with the second blank on the outside and the first blank inside, so that the blank stack is deformed into the double-layer crown spring in steps. S4. Blanking and forming: Using the second positioning hole as the positioning reference, cut off the connection between the second connecting strip and the double-layer crown spring, so that the double-layer crown spring is blanked and formed.

8. The manufacturing method according to claim 7, characterized in that: The second continuous material has a frame-shaped structure that completely surrounds the second blank. The second continuous material has auxiliary positioning holes with a synchronous distance machined on another strip area opposite to the strip area where the second positioning hole is located.

9. The manufacturing method according to claim 7, characterized in that: The first blank has a comb-shaped structure, including a first strip portion, a plurality of cantilever spring pieces equidistantly arranged on a first side of the first strip portion, and a plurality of L-shaped riveting pieces equidistantly arranged on a second side of the first strip portion. The L-shaped riveting pieces are vertically connected to the first strip portion, and the first connecting strip connects the middle of the second side of the first strip portion to the first continuous material. The second blank has a grid structure, including a second strip portion, a third strip portion parallel to the second strip portion, and a plurality of bridge-type spring pieces equidistantly connecting the second strip portion and the third strip portion. The second strip portion is provided with a locking hole matching the position of the L-shaped riveting piece. In the overlapping riveting step, the end of the L-shaped riveting piece is inserted into the locking hole, and then the L-shaped riveting piece is riveted to form a hook that hooks the locking hole. The first strip portion encloses to form the first support ring, the second strip portion encloses to form the second support ring, and the third strip portion encloses to form the third support ring.

10. The manufacturing method according to claim 9, characterized in that: During the blank preparation process, the initial lengths of the second strip and the third strip are equal to the length of the first strip. While keeping the length of the bridge spring constant, the second strip and the third strip are extended synchronously by 5-15% through rolling.

11. The manufacturing method according to claim 9, characterized in that: Between the overlapping riveting step and the blank rounding step, there is also a torsion processing step: while keeping the second strip portion parallel to the third strip portion, the second strip portion is fixed and the third strip portion is pulled off-center along the conveying direction of the material belt, so that the bridge spring and the cantilever spring are tilted in the same direction.

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