Copper-clad aluminum structure for inductor connecting terminal

Abstract

The utility model relates to the technical field of inductor terminals, in particular to a copper-clad aluminum structure for an inductor connecting terminal. The connector comprises a connecting terminal and a copper-clad aluminum structure processed at the tail end of the connecting terminal, wherein the copper-clad aluminum structure is provided with a wrapping layer and a solid layer from outside to inside in sequence; the joint of the wrapping layer and the insulating paint layer protrudes outwards to form a protruding step. According to the utility model, the part, which is not coated with the insulating paint, of the tail end of the solid layer is inserted into the copper sleeve, and the wrapping layer extrudes part of the insulating paint layer to form the extrusion layer obliquely wrapping the solid layer, so that the wrapping is tight, and the erosion of the external environment is effectively isolated; the wrapping layer is in close contact with the solid layer, so that the conductivity is good; and a copper surface capable of being directly welded is provided, so that the weldability of the terminal is improved.

Description

Technical Field

[0001] This utility model relates to the field of inductor terminal technology, and specifically to a copper-clad aluminum structure for inductor connection terminals. Background Technology

[0002] If pure aluminum wire is used for inductor connection terminals, soldering the leads presents challenges. A dense oxide film (Al2O3) forms on the surface of pure aluminum wire, with a melting point as high as 2050℃, far exceeding the melting point of wave soldering solder (232℃). This results in ineffective solder wetting, leading to a solder joint detachment rate as high as 20% and poor soldering performance. Furthermore, existing copper-clad aluminum structures have open ends, which can lead to electrochemical corrosion. Existing technologies, such as the solution disclosed in Chinese Patent Publication No. CN218997102U, involve wrapping a copper layer around the aluminum wire to create a copper-aluminum composite structure. However, this copper-clad aluminum structure still faces challenges in practical applications. Currently, most terminals have an insulating varnish layer. Properly handling the connection between the varnish layer and the insulating varnish layer, and ensuring proper protection at the joints to prevent poor contact and insulation failure, are crucial issues that urgently need to be addressed to ensure product reliability. Utility Model Content

[0003] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a copper-clad aluminum structure for inductor connection terminals.

[0004] The technical solution adopted in this utility model is as follows:

[0005] A copper-clad aluminum structure for an inductor connection terminal includes a connection terminal and a copper-clad aluminum structure processed at the end of the connection terminal. The copper-clad aluminum structure has a wrapping layer and a solid layer arranged sequentially from the outside to the inside. An insulating varnish layer is sleeved on the solid layer. The joint between the wrapping layer and the insulating varnish layer bulges outward to form a raised step. The wrapping layer squeezes out part of the insulating varnish layer to form an extruded layer that is inclined and wraps around the solid layer.

[0006] This technical solution is a copper-clad aluminum structure specifically designed for inductor connection terminals. It involves inserting the uncoated portion of the solid layer at its end into a copper sleeve, causing the sleeve to compress part of the insulating varnish layer, forming an extruded layer that obliquely wraps around the solid layer. This creates a tight contact between the copper sleeve and the solid layer, forming a complete inductor connection terminal. This solution solves the problems of electrochemical corrosion and poor weldability of pure aluminum wires caused by exposed aluminum cores in the lead cross-section of copper-clad aluminum wires and exposed copper-aluminum composite conductive terminal substrates by wrapping the pure aluminum wire end with a copper sleeve and forming a metallurgical bond. If necessary, at least one reinforcing indentation is machined around the perimeter of the cladding layer using specialized tools; if necessary, sealant and anti-rust oil are applied to the joint of the raised step to prevent external environmental corrosion of the copper-aluminum contact interface.

[0007] In addition, the copper-clad aluminum structure for inductor connection terminals proposed above according to this utility model also has the following additional technical features:

[0008] According to one embodiment of the present invention, the wrapping layer is a copper sleeve. The wrapping layer wraps around the end of the solid layer in a full circumference and squeezes a portion of the insulating varnish layer to form a squeezed layer. The area covered by the wrapping layer includes the end of the solid layer and the squeezed layer.

[0009] In this technical solution, the free end of the copper sleeve extends to the surface of the insulating varnish layer through a full circumferential wrapping method, completely covering the edge of the insulating varnish layer cross-section. A full circumferential metallurgical bond is formed between the copper sleeve and the aluminum core.

[0010] According to one embodiment of the present invention, the solid layer is an aluminum wire with a circular or flat cross-section, with a certain length of the end of the solid layer exposed outside, and the remaining part having an insulating varnish layer on its surface.

[0011] In this technical solution, taking a circular cross-section as an example, the diameter of the round aluminum wire is 4.0mm, the thickness of the insulating varnish layer is 50μm, and the exposed length of the aluminum core is 15mm; the inner diameter of the copper sleeve is 3.8mm (0.2mm interference fit), the total length is 17mm, and the insulating varnish layer is 2.0mm thick.

[0012] Taking a flat cross-section as an example, the flat aluminum wire has a cross-section of 5mm×2mm, an insulating varnish layer thickness of 80μm, and an exposed aluminum core length of 20mm; the copper sleeve has an inner diameter of 5.5mm×2.5mm (with a clearance fit of 0.5mm), a total length of 22mm, and is covered with an insulating varnish layer of 2.0mm.

[0013] According to one embodiment of the present invention, the periphery of the wrapping layer is processed with at least one reinforcing indentation, which is a groove spaced apart on the outside of the extruded layer.

[0014] In this technical solution, the reinforcing indentation is enhanced by adding downwardly spaced grooves to increase the bonding strength. The reinforcing indentation is engaged using a specialized tool, such as pliers.

[0015] According to one embodiment of the present invention, the reinforcing indentation forms a wave-shaped reinforcing structure on the inner wall of the wrapping layer, thereby creating a pre-tightening force on the extrusion layer and the internal solid layer.

[0016] According to one embodiment of the present invention, the joint of the raised step is coated with sealant and anti-rust oil.

[0017] In this technical solution, sealant and rust-preventive oil are just two examples of protective materials. Other materials that can prevent external environmental corrosion of the copper-aluminum contact interface are also within the scope of protection. Protective materials extend the service life of the connection terminals.

[0018] In addition, to improve the metallurgical bond strength and conductivity between copper and aluminum, a transition layer, such as tin or nickel, can be added between the cladding layer and the solid layer, that is, between copper and aluminum.

[0019] Compared with the prior art, this utility model has the following advantages:

[0020] By inserting the uncoated portion of the solid layer into a copper sleeve and squeezing part of the insulating varnish layer with the wrapping layer, an extruded layer is formed that is tilted and wrapped around the solid layer. This tight wrapping effectively isolates the solid layer from external environmental corrosion. Furthermore, the wrapping layer and the solid layer are in close contact, resulting in good conductivity. The copper surface that can be directly soldered is provided, improving the solderability of the terminals. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a structure with a solid layer and a circular cross-section.

[0022] Figure 2 This is a schematic diagram of a structure with a flat cross-section for the solid layer.

[0023] Figure 3 yes Figure 1 A schematic diagram of a structure with reinforcing indentations.

[0024] Figure 4 yes Figure 2 A schematic diagram of a structure with reinforcing indentations.

[0025] In the diagram: 1. Wrapping layer; 2. Solid layer; 3. Insulating varnish layer; 4. Extrusion layer; 5. Raised step; 6. Reinforcing indentation. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0027] Example 1

[0028] like Figures 1 to 4 As shown, this embodiment provides a copper-clad aluminum structure for inductor connection terminals, including connection terminals and a copper-clad aluminum structure processed at the end of the connection terminals. The copper-clad aluminum structure is provided with a wrapping layer 1 and a solid layer 2 from the outside to the inside. An insulating varnish layer 3 is sleeved on the solid layer 2. The joint between the wrapping layer 1 and the insulating varnish layer 3 protrudes outward to form a raised step 5. The wrapping layer 1 squeezes part of the insulating varnish layer 3 to form an extruded layer 4 that is inclined and wrapped around the solid layer 2.

[0029] like Figures 1 to 4 As shown, this technical solution is a copper-clad aluminum structure specifically designed for inductor connection terminals. By inserting the uncoated portion of the solid layer 2 into a copper sleeve, the copper sleeve compresses a portion of the insulating varnish layer 3, forming an inclined extruded layer 4 that wraps around the solid layer 2. This creates a tight contact between the copper sleeve and the solid layer 2, forming a complete inductor connection terminal. This technical solution solves the problems of electrochemical corrosion and poor weldability of pure aluminum wires caused by exposed aluminum cores in the lead cross-section of copper-clad aluminum wires and exposed substrates in copper-aluminum composite conductive terminals by wrapping the pure aluminum wire end with a copper sleeve and forming a metallurgical bond. If necessary, at least one reinforcing indentation 6 is machined around the perimeter of the cladding layer 1 using a special tool; if necessary, sealant and anti-rust oil are applied to the joint of the raised step 5 to prevent external environmental corrosion of the copper-aluminum contact interface.

[0030] In addition, the copper-clad aluminum structure for inductor connection terminals proposed above according to this utility model also has the following additional technical features:

[0031] According to one embodiment of the present invention, the wrapping layer 1 is a copper sleeve. The wrapping layer 1 wraps around the end of the solid layer 2 in a full circumferential direction and squeezes a portion of the insulating varnish layer 3 to form a squeezed layer 4. The area covered by the wrapping layer 1 includes the end of the solid layer 2 and the squeezed layer 4.

[0032] In this technical solution, the free end of the copper sleeve extends to the surface of the insulating varnish layer 3 through a full circumferential wrapping method, completely covering the edge of the cross-section of the insulating varnish layer 3. A full circumferential metallurgical bond is formed between the copper sleeve and the aluminum core.

[0033] According to one embodiment of the present invention, the solid layer 2 is an aluminum wire with a circular or flat cross-section, and a certain length of the end of the solid layer 2 is exposed outside, while the surface of the remaining part is covered with an insulating varnish layer 3.

[0034] In this technical solution, taking a circular cross-section as an example, the diameter of the round aluminum wire is 4.0mm, the thickness of the insulating varnish layer is 50μm, and the exposed length of the aluminum core is 15mm; the inner diameter of the copper sleeve is 3.8mm (0.2mm interference fit), the total length is 17mm, and the insulating varnish layer is 32.0mm thick.

[0035] Taking a flat cross-section as an example, the flat aluminum wire has a cross-section of 5mm×2mm, an insulating varnish layer of 3mm thickness of 80μm, and an exposed aluminum core length of 20mm; the copper sleeve has an inner diameter of 5.5mm×2.5mm (with a clearance fit of 0.5mm), a total length of 22mm, and covers an insulating varnish layer of 32.0mm.

[0036] like Figures 3 to 4 As shown, the periphery of the wrapping layer 1 is processed with at least one reinforcing indentation 6, which is a groove spaced apart on the outside of the extrusion layer 4.

[0037] In this technical solution, the reinforcing indentation 6 is enhanced by adding downwardly spaced grooves to increase the bonding strength. The reinforcing indentation 6 is engaged using a special tool, such as pliers.

[0038] According to one embodiment of the present invention, the reinforcing indentation 6 forms a wave-shaped reinforcing structure on the inner wall of the wrapping layer 1, thereby creating a pre-tightening force on the extrusion layer 4 and the internal solid layer 2.

[0039] According to one embodiment of the present invention, the joint of the raised step 5 is coated with sealant and anti-rust oil.

[0040] In this technical solution, sealant and rust-preventive oil are just two examples of protective materials. Other materials that can prevent external environmental corrosion of the copper-aluminum contact interface are also within the scope of protection. Protective materials extend the service life of the connection terminals.

[0041] In addition, to improve the metallurgical bond strength and conductivity between copper and aluminum, a transition layer, such as tin or nickel, can be added between the cladding layer and the solid layer, that is, between copper and aluminum.

[0042] The usage process of the above embodiments is as follows:

[0043] like Figures 1 to 2 As shown, the terminals of the inductor have either round or flat cross-sections. Different types of terminals should be selected according to the needs.

[0044] The end of the terminal block is exposed for a certain length, while the remaining untreated portion is covered with an insulating varnish layer 3. A copper wrapping layer 1 is used to wrap the end of the solid layer 2 and part of the insulating varnish layer 3 in its entire circumference. By squeezing, the wrapping layer 1 and part of the insulating varnish layer 3 are brought into contact, thereby forming an inclined extrusion layer 4. This achieves close contact between the wrapping layer 1 and the solid layer 2, forming a metallurgical bond.

[0045] like Figures 3 to 4 As shown, if it is necessary to enhance the structural stability, at least one reinforcing indentation 6 is processed around the periphery of the wrapping layer 1 using a special tool. This indentation serves as a spacer groove, forming a wave-shaped reinforcing structure on the inner wall of the wrapping layer 1, which generates a pre-tightening force on the extrusion layer 4 and the inner solid layer 2.

[0046] To prevent external environmental corrosion of the copper-aluminum contact interface, protective materials such as sealant and anti-rust oil are applied to the raised step 5 formed at the joint between the wrapping layer 1 and the extrusion layer 4. This ensures the sealing of the structure, prevents corrosion problems caused by inadequate coverage of the open end of the copper sleeve, and extends the service life of the connection terminal.

[0047] Although the present invention has been described in detail with reference to the accompanying drawings and preferred embodiments, it is not limited thereto. Various equivalent modifications or substitutions can be made to the embodiments of the present invention by those skilled in the art without departing from the spirit and essence of the present invention, and such modifications or substitutions should all be within the scope of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should also be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the scope of the claims.

Claims

1. A copper-clad aluminum structure for inductor connection terminals, characterized in that, It includes a connecting terminal and a copper-clad aluminum structure processed at the end of the connecting terminal. The copper-clad aluminum structure is provided with a wrapping layer (1) and a solid layer (2) from the outside to the inside. An insulating varnish layer (3) is sleeved on the solid layer (2). The joint between the wrapping layer (1) and the insulating varnish layer (3) is raised outward to form a raised step (5). The wrapping layer (1) squeezes part of the insulating varnish layer (3) to form an extruded layer (4) that is inclined to wrap around the solid layer (2).

2. The copper-clad aluminum structure for inductor connection terminals as described in claim 1, characterized in that, The wrapping layer (1) is a copper sleeve. The wrapping layer (1) wraps around the end of the solid layer (2) and squeezes a portion of the insulating varnish layer (3) to form a squeezed layer (4). The area covered by the wrapping layer (1) includes the end of the solid layer (2) and the squeezed layer (4).

3. The copper-clad aluminum structure for inductor connection terminals as described in claim 1, characterized in that, The solid layer (2) is an aluminum wire with a circular or flat cross-section. A certain length of the end of the solid layer (2) is exposed, and the rest of the surface has an insulating varnish layer (3).

4. The copper-clad aluminum structure for inductor connection terminals as described in claim 1, characterized in that, The periphery of the wrapping layer (1) is processed with at least one reinforcing indentation (6), which is a groove spaced apart on the outside of the extrusion layer (4).

5. The copper-clad aluminum structure for inductor connection terminals as described in claim 4, characterized in that, The reinforcing indentation (6) forms a wave-shaped reinforcing structure on the inner wall of the wrapping layer (1), and forms a pre-tightening force on the extrusion layer (4) and the inner solid layer (2).

6. The copper-clad aluminum structure for inductor connection terminals as described in claim 1, characterized in that, The joint of the raised step (5) is coated with sealant and anti-rust oil.

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