Wire resistance welding method and application

Abstract

The invention discloses a wire resistance welding method and application, and belongs to the field of wire welding, and the wire resistance welding method comprises the following steps: S1, carrying out wire cutting, aluminum foil layer stripping and insulating layer stripping treatment on a wire, and exposing a wire conductor; and S3, an electrode makes contact with the pre-tinning layer, the wire conductor is pressed, the electrode is powered on, the pre-tinning layer generates resistance heat, the pre-tinning layer is melted, and resistance welding is achieved. According to the wire resistance welding method and the application, the pre-tinning layer is melted by utilizing the instantaneous heating of the electrode, and the heating time is short, so that the insulating layer of the wire is not burnt and damaged by the back shrinkage, and the wire which is not resistant to temperature can be adopted, and the cost is greatly saved.

Description

Technical Field

[0001] The invention belongs to the field of wire welding, and in particular relates to a wire resistance welding method and application. Background Art

[0002] In today's era of rapid development of information technology, high-speed cables are the key carriers of data transmission, and their performance and quality play a vital role in the efficient operation of various electronic equipment and systems. Among them, PCB products occupy an important position in the field of high-speed cables, and the Hotbar welding process has been widely used in the welding process of PCB products due to its unique advantages.

[0003] The Hotbar welding process, also known as pulse hot pressing welding, transfers heat to the welding part through the hot pressing head to melt the pre-placed solder, thereby achieving a reliable connection between the electronic components and the circuit board. This process can meet the needs of high-precision and small-size welding, and plays an indispensable role in the production of high-speed cable PCB products. However, with the continuous increase in data transmission rates, especially the emergence of PCIe Gen5 and higher-speed products, the Hotbar welding process faces many severe challenges.

[0004] Since the Hotbar welding process requires continuous heating in a high temperature environment to ensure that the solder can fully melt and achieve a good welding effect. In the application scenarios of PCIe Gen5 and higher speed products, in order to ensure the SI performance of the product, the insulation retention length is required to be 0-2.0mm, and the defect rate of using non-heat-resistant materials is very high. In order to ensure the stability and reliability of the product during the welding process and subsequent use, insulation materials with better heat resistance must be selected. However, this choice brings a series of problems.

[0005] First, when the PCB is matched with heat-resistant wires, the insulation layer is very likely to shrink or even burn and melt after the Hotbar welding process. Such damage to the insulation layer will directly affect the electrical performance of the product, such as causing unstable signal transmission and impedance mismatch, which will seriously affect the SI (signal integrity) performance of the product. In the process of high-speed data transmission, the quality of SI performance directly determines whether the data can be transmitted accurately and quickly. Damage to the insulation layer will undoubtedly cause a fatal blow to the overall performance of the high-speed cable.

[0006] Secondly, the cost of heat-resistant wire is as much as 50% higher than that of non-heat-resistant wire. This makes the product have no cost advantage in the market competition. With the increasingly fierce market competition, product cost has become one of the key factors affecting its market competitiveness. Excessive cost will not only squeeze the profit margin of the enterprise, but also lead to excessively high product prices, loss of price advantage, and thus affect the market share of the product.

[0007] Furthermore, currently commonly used heat-resistant materials mainly contain fluorine. With the continuous enhancement of global environmental awareness and increasingly stringent environmental regulations, fluorine-containing materials may not meet environmental protection requirements in future production and applications. This not only brings potential legal risks to enterprises, but also does not conform to the concept of sustainable development.

[0008] In summary, the application of Hotbar welding technology in the welding process of high-speed cable PCB products currently faces many difficulties. There is an urgent need for a method that can solve the technical problem of shrinkage / scalding and melting loss when welding PCB products with non-heat-resistant insulated wires, so as to achieve the application of non-heat-resistant wires on PCIe Gen5 and higher-speed products, achieve the purpose of reducing costs, meeting environmental protection requirements, and improving the comprehensive competitiveness of products in the market. Summary of the invention

[0009] The object of the present invention is to provide a wire resistance welding method and application to overcome at least one of the above-mentioned defects in the prior art.

[0010] To achieve this object, the present invention adopts the following technical solutions:

[0011] The present invention provides a wire resistance welding method, comprising the following steps: S1: cutting the wire, stripping the aluminum foil layer and the insulation layer to expose the wire conductor, S2: overlapping the wire conductor with the pre-tinning layer on the circuit board pad, S3: bringing the electrode into contact with the pre-tinning layer and pressing the wire conductor, energizing the electrode so that the pre-tinning layer generates resistance heat, melts the pre-tinning layer, and realizes resistance welding.

[0012] Preferably, in step S1, the insulation layer of the wire is made of a temperature-intolerant material.

[0013] Preferably, after the aluminum foil layer and the insulation layer are stripped in step S1, the straight-line distance between the end of the insulation layer and the end of the aluminum foil layer is 0-2.0 mm.

[0014] Preferably, in step S3, parallel resistance welding is used for welding.

[0015] Preferably, in step S3, the electrode has a plurality of welding positions.

[0016] Preferably, in step S3, the electrodes are energized for welding with a current of 0.6-1.4 A, the welding time is 70-95 ms, the welding interval is 3-12 ms, and the cooling time is 80-170 ms.

[0017] Preferably, the temperature-intolerant material is polyethylene or polypropylene.

[0018] The present invention also provides an application of the wire resistance welding method in preparing a high-speed connector.

[0019] Preferably, the high-speed connector comprises a wire having an insulation layer, and the insulation layer is a temperature-intolerant material.

[0020] The beneficial effects of the present invention are:

[0021] 1. The pre-tinned layer is melted by instantaneous heating of the electrode. Since the heating time is short, the insulation layer of the wire will not be burned or melted due to shrinkage. Therefore, non-heat-resistant wire can be used, which greatly saves costs.

[0022] 2. The wire can be welded after simple wire cutting, stripping of aluminum foil and insulation layer, which saves the work of trimming the ground wire.

[0023] 3. Only three simple steps are needed to increase welding efficiency by 10%.

[0024] 4. Parallel resistance welding is used for welding, which not only has high welding strength, but also has stable welding quality, small heat-affected zone and high production efficiency.

[0025] 5. The electrode has several welding positions, which can realize one-time welding and improve welding efficiency.

[0026] 6. The wire resistance welding method of the present invention solves the technical problem of shrinkage / scalding and melting loss after welding of PCB products with heat-resistant insulating wires, thereby allowing heat-resistant wires to be used in PCIe Gen5 and higher-speed products, reducing costs and meeting environmental protection requirements.

[0027] 7. Compared with finished products of heat-resistant wires, non-heat-resistant wires can save 50% of the cost and meet future environmental protection requirements. DETAILED DESCRIPTION

[0028] The present invention will now be further described in conjunction with specific implementation methods.

[0029] Contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field. In the description of the present invention, it should be understood that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicating the orientation or position relationship are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third" and the like are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0030] Embodiment 1:

[0031] A wire resistance welding method provided in this embodiment includes the following steps:

[0032] S1: Cut the wire, strip the aluminum foil layer and the insulation layer, so that the straight-line distance between the end of the insulation layer and the end of the aluminum foil layer is 0-2.0mm, and the wire conductor is exposed. The wire can be welded after simple pre-treatment of cutting the wire, stripping the aluminum foil layer and stripping the insulation layer, saving the station for trimming the ground wire. This not only simplifies the preparation process before welding, but also reduces the increase in labor costs and potential risks of operational errors caused by complex procedures, greatly improving production efficiency. Among them, the insulation layer of the wire is a heat-resistant material. Since the insulation layer of the wire is made of heat-resistant material, the cost can be greatly reduced compared to heat-resistant material. The heat-resistant material in this embodiment is polyethylene, and it can also be polypropylene in other embodiments.

[0033] S2: Lap the wire conductor onto the pre-tinned layer on the circuit board pad.

[0034] S3: The electrode is brought into contact with the pre-tin layer and presses the wire conductor, and the electrode is energized and welded with a current of 0.6-1.4A. The welding time is 70-95ms, the welding interval is 3-12ms, and the cooling time is 80-170ms, so that the pre-tin layer generates resistance heat, and the pre-tin layer is melted by the instantaneous heating of the electrode to achieve resistance welding. The parallel resistance welding method is used for welding, which not only has high welding strength, but also has stable welding quality, small heat-affected zone, and high production efficiency. Specifically, the parallel resistance welding method is used for welding. After the electrode is in contact with the pre-tin layer and energized, the instantaneous resistance heat causes the pre-tin layer to melt rapidly to achieve welding. The solder joint structure formed by this welding method is compact and can withstand large tensile and shear forces, ensuring that the welding part has high strength. In practical applications, such as the connection of high-speed cables, high welding strength ensures that the product is not prone to problems such as loosening and falling off during long-term use, even if it is pulled or vibrated by external forces, thereby ensuring the reliability and stability of the product. During the parallel resistance welding process, the contact between the electrode and the pre-tin layer is relatively uniform, and the current distribution is relatively stable, so that the quality difference of each welding is small. This stable welding quality helps to improve product consistency and reduce the defective rate. In large-scale production, the stability of product quality is crucial to the brand image and market reputation of the company, and can effectively reduce after-sales costs and customer loss caused by product quality problems. Due to the short heating time during welding, the heat can be quickly concentrated on the pre-tin layer to achieve welding, and the thermal impact range of the surrounding wire insulation layer is small. This prevents the wire insulation layer from shrinking, scalding, melting, etc. due to long-term heating, thereby ensuring the integrity and performance of the insulation layer. For high-speed cable products, the good performance of the insulation layer is crucial to the stability and accuracy of signal transmission. Avoiding damage to the insulation layer can effectively improve the electrical performance and SI (signal integrity) performance of the product, and ensure the accuracy and reliability of data during high-speed transmission. Due to the short heating time, the wire insulation layer is not shrunk, scalded, or melted, so non-heat-resistant wire can be used, which greatly saves costs. The entire welding process only requires three simple steps, which is simpler and more efficient than traditional welding processes. After actual testing, the welding efficiency has increased by 10%, which means that more products can be welded in the same production time, further improving production efficiency and bringing more economic benefits to the company.

[0035] Among them, the electrode has several welding positions to improve welding efficiency. Compared with the existing double ground wire and single ground wire products, the present invention can achieve one-time welding. This advantage not only saves the time and energy consumption required for multiple welding, but also avoids the cumulative errors and additional thermal damage to the weldment that may occur during multiple welding processes. Successful welding in one time can improve production efficiency, while reducing the product defect rate caused by multiple welding, further improving the overall quality and production efficiency of the product.

[0036] Embodiment 2:

[0037] This embodiment provides an application of the wire resistance welding method of embodiment 1 in the preparation of a high-speed connector. Among them, the high-speed connector includes a wire, and the wire has an insulating layer, and the insulating layer is a heat-resistant material. The wire resistance welding method of embodiment 1 solves the technical problem of shrinkage / scalding and melting loss after welding of PCB products with heat-resistant insulated wires, so that heat-resistant wires can be used in PCIe Gen5 and higher-speed products, reducing costs and meeting environmental protection requirements. Compared with finished products of heat-resistant wires, heat-resistant wires can save 50% of costs and meet future environmental protection requirements.

[0038] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, it should be understood by those skilled in the art that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wire resistance welding method, characterized in that: The following steps are involved: S1: Cut the wire, strip the aluminum foil layer and the insulation layer; S2: Lap the wire conductor onto the pre-tinned layer on the circuit board pad; S3: The electrode is brought into contact with the pre-tinned layer and presses the wire conductor, and the electrode is energized so that the pre-tinned layer generates resistance heat, melts the pre-tinned layer, and realizes resistance welding.

2. The wire resistance welding method according to claim 1, characterized in that: In step S1, the insulation layer of the wire is made of a temperature-intolerant material.

3. The wire resistance welding method according to claim 1, characterized in that: After the aluminum foil layer and the insulation layer are stripped in step S1, the straight-line distance between the end of the insulation layer and the end of the aluminum foil layer is 0-2.0 mm.

4. The wire resistance welding method according to claim 1, characterized in that: In step S3, parallel resistance welding is used for welding.

5. The wire resistance welding method according to claim 1, characterized in that: In step S3, the electrode has a plurality of welding positions.

6. The wire resistance welding method according to claim 1, characterized in that: In step S3, the electrodes are energized for welding with a current of 0.6-1.4 A, the welding time is 70-95 ms, the welding interval is 3-12 ms, and the cooling time is 80-170 ms.

7. The wire resistance welding method according to claim 2, characterized in that: The non-heat-resistant materials are polyethylene or polypropylene.

8. Use of the wire resistance welding method according to any one of claims 1 to 7 in the preparation of high-speed connectors.

9. The use according to claim 8, characterized in that: The high-speed connector includes a wire having an insulation layer, and the insulation layer is a temperature-intolerant material.