A multi-row high-density pin connector local gold removal tin soldering device and method

Abstract

The application discloses a multi-row high-density pin connector local gold-removing tin-coating device and method, and relates to the technical field of connector manufacturing. The multi-row high-density pin connector local gold-removing tin-coating device comprises a clamping mechanism, a heat management module, an air curtain mechanism, a tin bath and a lifting driving module; the clamping mechanism is used for positioning the connector and making the pins extend out; the heat management module is used for refrigerating and temperature-controlling the connector body; the air curtain mechanism comprises an enclosing ring, the inner wall of the enclosing ring is provided with horizontally sprayed first air outlets and downwardly inclined second air outlets; and the lifting driving module drives the pins to immerse in the tin liquid. The downward airflow generated by the second air outlets is used to resist the capillary climbing force of the tin liquid along the pin surface, an air-liquid tension balance surface is formed at the tin-coating boundary, the local tin-coating depth is controlled, and the problems that the tin liquid easily climbs up to contaminate the body and manual operation is difficult for the high-density pin connector are solved.

Description

Technical Field

[0001] This application relates to the field of connector processing technology, specifically to a device and method for partial gold removal and tinning of multi-row high-density pin connectors. Background Technology

[0002] In high-reliability electronic assembly fields (such as aerospace and military electronics), multi-row high-density pin connectors (such as HRM type and micro-D type) are increasingly widely used. A significant characteristic of these connectors is their extremely high pin density (pin spacing is typically less than 1.27mm), and the extremely close distance between the connector body (usually made of high-temperature resistant insulating material) and the pin roots (often less than 3mm). The pins of these connectors extend from below the body and are arranged in multiple rows (e.g., 10 to 20 rows) along the arrangement direction, but each row typically contains only two columns, resulting in a comb-like layout of "multi-row × two columns." According to relevant military standards and process specifications, to eliminate the risk of "gold brittleness," gold-plated pins must undergo a rigorous "gold removal and tinning" process before soldering, which involves removing the surface gold layer and pre-coating with a layer of fresh solder.

[0003] The existing gold-removal tin-plating process mainly faces the following irreconcilable technical contradictions:

[0004] First, the accessibility of manual operation fails. For multi-row high-density pin connectors, the physical gap between adjacent pins is extremely narrow (even less than 0.8mm). The width of the soldering tip of a conventional soldering iron is much larger than this gap, making it impossible to reach into the base of the pin for targeted heating. If forced, it is very easy to cause a "bridging" short circuit between adjacent pins, or poor contact leading to cold solder joints. In addition, manual operation relies entirely on the worker's experience, making it impossible to guarantee the consistency of the soldering height of hundreds or thousands of pins.

[0005] Secondly, there's the challenge of "capillary climb" in the overall immersion soldering process. To address the difficulty of manual operation, current technology often involves immersing the connector pins entirely in molten solder (Sn-Pb or SAC alloy). However, this method introduces a new drawback: due to the extremely high surface tension coefficient and wettability of molten solder, when the pins are vertically withdrawn from the solder surface, a strong capillary effect occurs on the pin surface, causing the solder to continuously "climb" upwards along the pin surface. Given the extremely short safety distance between the high-density connector body and the pin root (typically only 2mm~4mm), once capillary climb occurs, the solder can easily overflow the pin root and directly contact or even cover the connector's insulating body. This not only causes the connector body to overheat and deform or degrade, but the residual solder balls can also cause electrical short circuits between adjacent pins during subsequent PCB assembly, creating a fatal quality hazard.

[0006] Third, the limitations of existing protective measures. To limit the solder climb height during immersion soldering, existing technologies attempt two solutions: one is the physical mask method, which involves applying solder resist or installing fixtures at the base of the leads. However, solder resist is difficult to apply evenly in dense gaps and is difficult to clean, easily leaving chemical contaminants; precision fixtures are expensive and block the base of the leads, preventing that area from being effectively wetted. The second is the scraping / centrifugal method, which involves scraping off excess solder with a scraper or rotating it after immersion. This method is a "post-treatment" approach, which easily produces sharp spikes or irregular solder bumps, which worsens the lead geometry and affects subsequent insertion.

[0007] In summary, how to overcome the limitations of the natural law of "capillary climb" in fluid mechanics without using physical masks, and achieve micron-level precision control of local tinning depth for multi-row high-density pin connectors, while ensuring that the connector body is not damaged, is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0008] To address the technical problems in the prior art, this application provides a device and method for partial de-goldening and tinning of multi-row high-density pin connectors.

[0009] This application provides a device and method for partial de-goldening and desoldering of a multi-row high-density pin connector, which adopts the following technical solution:

[0010] A partial gold-plating removal device for multi-row high-density pin connectors includes:

[0011] The clamping mechanism includes a positioning base and a fixing component. The positioning base has a positioning cavity that matches the outline of the connector body. The lower end face of the positioning base has a through hole communicating with the positioning cavity. The positioning cavity is used to accommodate the connector body and allow multiple rows of pins of the connector to extend vertically downward from the through hole. The multiple rows of pins are arranged in multiple rows along the arrangement direction, with each row of pins containing only two columns. The fixing component is detachably connected to the positioning base and is used to fix the connector in the positioning cavity.

[0012] A thermal management module includes a thermoelectric semiconductor element disposed within the positioning base, the cooling surface of the thermoelectric semiconductor element facing the positioning cavity, for controlling the temperature of the connector body;

[0013] An air curtain mechanism includes a barrier ring, a first air injection component, and a second air injection component. The barrier ring is fixed to the lower end face of the positioning base and surrounds the radial outer side of the through hole. The inner wall of the barrier ring has a plurality of first air outlets and a plurality of second air outlets located below the first air outlets. The second air outlets are distributed on opposite inner walls of the barrier ring along the arrangement direction of the pins. The number of second air outlets on each side corresponds to the number of rows of pins, such that each second air outlet on each side is aligned with an adjacent column of pins in a row. Thus, the second vents on both sides of the enclosure ring correspond to the two columns of pins in each row of pins. The airflow acts directly on the surface of each column of pins from both sides without penetrating the shield of multiple columns of pins. The first gas injection component is used to supply inert gas to the first vent, and the second gas injection component is used to supply gas to the second vent. The second vent is used to spray gas at an angle downward relative to the horizontal direction to generate downward gas flow pressure to resist the capillary climbing force of the molten solder along the surface of the pin, forming a gas-liquid tension balance surface at the tinning boundary of the pin.

[0014] A tin bath is used to hold molten tin and keep the molten tin in a molten state.

[0015] The lifting drive module has its moving end connected to the positioning base and is used to drive the positioning base and the connector on it to move up and down in the vertical direction. The lifting drive module immerses the pin into the molten solder in the solder bath according to a preset depth and positions the second vent hole at a preset height above the molten solder surface.

[0016] A method for partial gold removal and soldering of a multi-row high-density pin connector, employing the aforementioned device for partial gold removal and soldering of a multi-row high-density pin connector, includes the following steps:

[0017] S1. Environment Setup: Install the connector into the positioning base and lock it in place using the fixing components. Activate the thermoelectric semiconductor element. The cooling surface of the thermoelectric semiconductor element lowers the temperature of the positioning base below a first preset temperature. Simultaneously, activate the first gas injection component, the second gas injection component, the first preheater, and the second preheater. Hot air is blown out from the first and second vents to raise the pin temperature to the second preset temperature. At the same time, nitrogen gas discharged from the first vent reduces the oxygen content in the processing area below a preset concentration, establishing a protective atmosphere. After the temperature of the positioning base stabilizes below the first preset temperature and the oxygen content in the processing area drops below the preset concentration, proceed to the next step.

[0018] S2, Servo Liquid Finding: The control unit drives the lifting drive module to immerse the pin into the molten solder in the solder bath based on the data fed back by the liquid level sensing unit, and dynamically compensates for the descent endpoint position based on the real-time liquid level height.

[0019] S3, Airflow obstruction: During the immersion of the pins in the solder bath, the airflow pressure of the second vent is adjusted. The second vents on both sides of the baffle ring spray airflow directly at the two columns of pins in each row from both sides, creating a gas-liquid tension balance surface at the soldering boundary of the pins to block the solder from climbing up.

[0020] S4. Vibration Desoldering: After the set soldering time is reached, when the control unit drives the lifting drive module to lift the positioning base and its pins to detach from the solder liquid, the high-frequency micro-vibration module is triggered to eliminate sticky wires, and the spray parameters of the second air outlet are adjusted to blow away the gaps between adjacent pins.

[0021] S5. Cooling and Unloading: The thermal management module cools the solder layer of the pins and then unloads the connector.

[0022] In some embodiments, in step S3, the control unit acquires the molten solder temperature data fed back by the temperature sensing unit in real time. And according to the formula Working air pressure at the second air outlet Dynamic correction is performed, among which As the reference pressure, The reference temperature for molten tin. This is the compensation coefficient.

[0023] In some embodiments, in step S1, the first gas flow rate output from the first outlet is... and the second gas flow rate output from the second outlet. The following relationship must be satisfied:

[0024] ,

[0025] ,

[0026] in, This refers to the cross-sectional area of ​​the through hole inside the enclosure ring. For the pin extension length, This refers to the total volume of the pins. The atmosphere replacement coefficient is... Preset rinsing time; For flow rate constant, The surface tension coefficient of molten tin. d is the contact angle, and d is the spacing between adjacent pins.

[0027] In some embodiments, the control unit drives the lifting drive module to lower the positioning base according to a segmented motion trajectory, wherein the segmented motion trajectory includes:

[0028] In the first stage, when the positioning base is more than a first preset distance from the molten tin surface, it descends at a first speed;

[0029] In the second stage, when the positioning base is within a second preset distance range from the molten tin surface, the speed of the positioning base decreases from the first speed to the second speed.

[0030] In the third stage, when the tip of the pin is within a third preset distance from the surface of the molten solder, it descends at a third speed until the pin is submerged to a set depth.

[0031] In the third stage, the control unit compares the real-time liquid level data of the liquid level sensing unit with the set immersion depth, and automatically compensates the stop position of the positioning base when the liquid level height deviates.

[0032] In summary, this application includes at least one of the following beneficial technical effects:

[0033] 1. By setting a second vent with an inclined downward spray angle, downward air pressure is generated at the pin tinning boundary to resist the capillary upward force of molten solder along the pin surface, forming a stable gas-liquid tension balance surface. This achieves precise control of local tinning depth and solves the technical problem of molten solder easily climbing upward and contaminating the connector body in traditional dip soldering processes. Since the connector pin array is a comb-like layout of "multi-row × two-column", the second vents on both sides of the enclosure ring correspond one-to-one with the two columns of pins. The airflow acts directly on the outer surface of each column of pins from both sides, which can evenly and effectively act on the tinning boundary of each pin. At the same time, the horizontally sprayed first vent creates a low-oxygen protective atmosphere to prevent the pins from oxidizing in a high-temperature environment.

[0034] 2. Active cooling of the connector body within the positioning cavity is achieved through thermoelectric semiconductor elements, combined with a water cooling mechanism to establish an efficient heat dissipation path, strictly controlling the connector body temperature within a safe range to avoid insulation layer aging or performance degradation due to high temperature conduction in the solder bath; at the same time, a gas preheater is used to heat the jet airflow to avoid thermal stress impact on the pins caused by cold airflow, thus achieving low temperature protection of the connector body and a gradient distribution of suitable process temperature in the pin processing area.

[0035] 3. By applying high-frequency micro-vibration in the vertical direction at the moment the pin is separated from the molten solder using a high-frequency micro-vibration module, the sticky wires at the pin tip are broken and excess molten solder is shaken off, eliminating common defects in traditional processes such as solder balls, solder bridging, and solder spikes; a closed-loop adaptive control system is constructed with the help of detection and control components to dynamically compensate for the immersion depth based on the real-time liquid level and automatically correct the air curtain pressure based on the molten solder temperature, thereby reducing the soldering height error. Attached Figure Description

[0036] Figure 1This is a schematic diagram of the overall structure of a partial gold-plating and tin-removing device for a multi-row high-density pin connector provided in an embodiment of this application;

[0037] Figure 2 yes Figure 1 A partially enlarged cross-sectional view of the clamping mechanism, thermal management module, and air curtain mechanism;

[0038] Figure 3 yes Figure 1 Schematic diagram of the piping connections for the air supply system and detection and control components of the water-cooling mechanism and air curtain mechanism;

[0039] Figure 4 This is a three-dimensional structural diagram of a connector in one embodiment of this application, showing the "multi-row × two-column" comb-like arrangement of the pins.

[0040] Explanation of reference numerals in the attached drawings: 1. Clamping mechanism; 11. Positioning base; 111. Through hole; 112. Heat dissipation channel; 113. Water inlet; 114. Water outlet; 12. Fixing component; 121. Cover plate; 122. Locking screw; 2. Thermal management module; 21. Thermoelectric semiconductor element; 3. Air curtain mechanism; 31. Enclosure ring; 311. First air outlet; 312. Second air outlet; 313. First cavity; 314. Second cavity; 315. First air inlet; 316. Second air inlet; 32. First air injection component; 321. First air pump; 322. First nitrogen cylinder; 323. First air valve; 324. ... 33. Second air injection assembly; 331. Second air pump; 332. Second air valve; 333. Second air supply hose; 34. First preheater; 35. Second preheater; 4. Lifting drive module; 41. Moving end; 5. Water cooling mechanism; 51. Water tank; 52. Circulation pump; 53. Inlet pipe; 54. Outlet pipe; 55. Return pipe; 56. Refrigerator; 6. Detection and control assembly; 61. Liquid level sensing unit; 62. Temperature sensing unit; 63. Mounting bracket; 64. Control unit; 7. High-frequency micro-vibration module; 8. Connector; 81. Body; 82. Pin; 9. Solder bath; 91. Electric heating element. Detailed Implementation

[0041] The technical solutions in the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. The described embodiments are only possible technical implementations of the present invention, but are not limited thereto. Other embodiments obtained by those skilled in the art in conjunction with the embodiments of the present invention without creative effort are also within the protection scope of the present invention.

[0042] This application mainly adopts a device and method for local gold removal and tinning of multi-row high-density pin connectors, which achieves the effects of precise control of the tinning area, avoiding tinning of non-target areas, and reducing costs and time. The following is a further detailed description of this application.

[0043] Example 1

[0044] Please refer to Figures 1 to 4 The multi-row high-density pin connector partial gold removal and soldering device provided in this application includes a clamping mechanism 1, a thermal management module 2, an air curtain mechanism 3, a solder bath 9, a lifting drive module 4, a high-frequency micro-vibration module 7, and a detection and control component 6. The clamping mechanism 1, thermal management module 2, and air curtain mechanism 3 are mounted on a positioning base 11. The moving end 41 of the lifting drive module 4 is connected to the positioning base 11, driving the positioning base 11 and the connectors 8 on it to move vertically up and down. The solder bath 9 is located below the positioning base 11 and is used to hold molten solder. The high-frequency micro-vibration module 7 is mounted on the positioning base 11. The detection and control component 6 is fixed to the side of the positioning base via a mounting bracket 63 and is signal-connected to each functional module. This structural combination enables the device to perform effective partial gold removal and soldering operations on multi-row high-density pin connectors, avoiding the problems of difficulty in accurately controlling the soldering area and easy damage to connector performance in traditional methods.

[0045] Please refer to Figure 4 The connector 8 addressed in this application includes a body 81 and multiple rows of pins 82 extending from below the body 81. The multiple rows of pins 82 are arranged in multiple rows along the arrangement direction (i.e., the length direction of the body 81), typically 10 to 20 rows, but each row of pins 82 contains only two columns, resulting in a comb-like layout of "multiple rows × two columns" for the entire pin array. This "multiple rows × two columns" pin arrangement is a crucial prerequisite for the effective functioning of the air curtain mechanism 3 in this application—since each row has only two columns of pins, the second air outlets 312 on both sides of the confining ring 31 can directly spray airflow from both sides onto the adjacent column of pins in each row of pins 82. The airflow from each second air outlet 312 only needs to traverse the short distance between the inner wall of the confining ring 31 and the nearest column of pins to reach the pin surface, without needing to penetrate the obstruction of multiple columns of pins. Therefore, the airflow pressure will not be severely attenuated due to the obstruction effect of the pin array, and can act uniformly and effectively on the tinned boundary of each pin 82. In this embodiment, the enclosure ring 31 and the positioning base 11 are integrally formed.

[0046] For specific details, please refer to... Figure 1 and Figure 2 The clamping mechanism 1 includes a positioning base 11 and a fixing assembly 12. The positioning base 11 has a positioning cavity that matches the outer contour of the connector 8, and a through hole 111 communicating with the positioning cavity is opened on the lower end face of the positioning base 11. The positioning cavity is used to accommodate the body 81 of the connector 8, and allows the multiple rows of pins 82 of the connector 8 to extend vertically downward from the through hole 111. Figure 4As shown, the multi-row pins 82 are arranged in multiple rows along the arrangement direction, with each row containing only two columns. The shape of the through-hole 111 is adapted to the "multi-row × two-column" layout of the pin array. The positioning base 11 can be made of aluminum alloy, which has good strength and heat dissipation performance; stainless steel can also be used, as it is more robust and durable. A heat dissipation channel 112 is also formed inside the positioning base 11. The two ends of the heat dissipation channel 112 extend to the side wall of the positioning base 11 to form a water inlet interface 113 and a water outlet interface 114, respectively, for communication with an external water cooling mechanism to achieve circulating cooling. The fixing component 12 is detachably connected to the positioning base 11 and is used to fix the connector 8 inside the positioning cavity. The fixing component 12 includes a cover plate 121 and a locking screw 122. The cover plate 121 covers the upper opening of the positioning base 11 and is fastened to the positioning base 11 by the locking screw 122, thereby pressing and fixing the body 81 of the connector 8 into the positioning cavity. Alternatively, the fixing component can also adopt a quick clamp structure for convenient and quick installation and removal of the connector. The positioning cavity matches the outer contour of the connector 8, ensuring accurate placement of the connector 8, and multiple rows of pins 82 extend from the through hole 111, providing a basis for subsequent soldering operations. The working process of the clamping mechanism 1 is as follows: the body 81 of the connector 8 is embedded into the positioning cavity, the pins 82 extend through the through hole 111, and then the fixing component 12 locks the connector 8, ensuring that the connector will not loosen or shift during subsequent lifting and lowering movements. Its technical effect is to achieve precise positioning and reliable clamping of the connector, ensuring the positional accuracy of the pins 82 relative to the through hole 111, laying the foundation for precise control of the soldering depth.

[0047] For specific details, please refer to... Figure 2The thermal management module 2 includes a thermoelectric semiconductor element 21 disposed within the positioning base 11. The thermoelectric semiconductor element 21 is embedded in the side or top wall of the positioning base 11, with its cooling surface facing the positioning cavity, for temperature control of the connector body 81. Simultaneously, the heating surface of the thermoelectric semiconductor element 21 faces the heat dissipation channel 112 to remove heat through a water-cooling medium. The thermoelectric semiconductor element 21 utilizes the thermoelectric effect to achieve cooling or heating functions. It can adjust the temperature as needed to ensure that the connector 8 is soldered under suitable temperature conditions. The thermoelectric semiconductor element 21 can be a common semiconductor cooling chip, which is small in size and highly efficient in cooling. Other types of thermoelectric elements can also be used, as long as they meet the temperature control requirements. By controlling the temperature of the connector body 81, damage to the connector due to excessive temperature can be prevented, and the quality of soldering can also be improved. The working process of the thermal management module 2 is as follows: when the connector body 81 needs to be cooled, the thermoelectric semiconductor element 21 is energized to generate the Peltier effect, the cooling surface absorbs the heat of the positioning cavity, and the heat generated by the heating surface is carried away by the circulating cooling water in the heat dissipation channel 112; when heating is required, the thermoelectric semiconductor element 21 can be reversed by changing the direction of the current; its technical effect is that it can accurately maintain the temperature of the connector body 81 within a preset range (usually controlled below 50°C), prevent the connector insulation layer from aging or being damaged due to high temperature, and at the same time form a reasonable temperature gradient distribution in conjunction with the air curtain mechanism.

[0048] For specific details, please refer to... Figures 1 to 4 The air curtain mechanism 3 includes a barrier ring 31, a first air injection component 32, and a second air injection component 33. The barrier ring 31 is fixed to the lower end face of the positioning base 11 and surrounds the radial outer side of the through hole 111. The inner wall of the barrier ring 31 has a plurality of first air outlet holes 311 and a plurality of second air outlet holes 312 located below the first air outlet holes 311. The barrier ring 31 has a first cavity 313 and a second cavity 314 that are independent of each other. The first air outlet holes 311 communicate with the first cavity 313, and the second air outlet holes 312 communicate with the second cavity 314. The side wall of the barrier ring 31 also has a first air inlet 315 that communicates with the first cavity 313 and a second air inlet 316 that communicates with the second cavity 314. The first air outlet 311 is positioned horizontally, while the second air outlet 312 is positioned at an angle of 30°–45° downward relative to the horizontal. Both the first air outlet 311 and the second air outlet 312 are matrix-type micropore structures distributed along the pin arrangement direction 82, with the diameter of each pore controlled within the range of 0.2 mm–0.5 mm to ensure airflow uniformity. The enclosure ring 31 can be made of high-temperature resistant engineering plastic or stainless steel.

[0049] It should be noted that the second vent 312 is distributed along the arrangement direction of the pins 82 on the inner walls of opposite sides of the enclosure ring 31. For example... Figure 4 As shown, since the pins 82 of the connector 8 are arranged in a comb-like pattern of "multiple rows × two columns", the number of second vent holes 312 on the inner wall of each side of the retaining ring 31 corresponds to the number of rows of pins 82 (for example, when there are 15 rows of pins 82, 15 second vent holes 312 are provided on each side of the retaining ring 31), so that each second vent hole 312 on each side is aligned with the adjacent column of pins in a row of pins 82. Thus, the second vent hole 312 on the left side of the retaining ring 31 is aligned with the left column of pins in each row of pins 82, and the second vent hole 312 on the right side of the retaining ring 31 is aligned with the right column of pins in each row of pins 82. The second vent holes 312 on both sides together cover all two columns of pins in each row of pins 82. This "two-sided opposing air hole layout" ensures that there are no other pins blocking the airflow path from the inner wall of the enclosure ring 31 to the surface of the nearest row of pins. The airflow pressure will not be attenuated due to penetrating multiple rows of pins, thus generating a sufficient gas-liquid tension balance surface at the tinning boundary of each pin 82 evenly and effectively.

[0050] The first gas injection assembly 32 is used to supply inert gas to the first gas outlet 311. Specifically, the first gas injection assembly 32 includes a first gas pump 321, a first nitrogen cylinder 322, a first gas valve 323, and a first gas delivery hose 324. The inlet of the first gas pump 321 is connected to the first nitrogen cylinder 322, and the outlet of the first gas pump 321 is connected to one end of the first gas delivery hose 324 via the first gas valve 323. The other end of the first gas delivery hose 324 is connected to the first gas inlet 315. The nitrogen output flow rate and pressure of the first gas outlet 311 can be controlled by adjusting the opening of the first gas valve 323. Nitrogen can be selected as the inert gas because it is chemically stable and can effectively prevent pin oxidation during the soldering process. Other inert gases such as argon can also be used. The second gas injection assembly 33 is used to supply gas to the second vent 312. The second gas injection assembly 33 specifically includes a second air pump 331, a second air valve 332, and a second gas delivery hose 333. The outlet of the second air pump 331 is connected to one end of the second gas delivery hose 333 via the second air valve 332, and the other end of the second gas delivery hose 333 is connected to the second air inlet 316. The second air pump 331 can draw ambient air or inert gas, compress it, and supply it to the second cavity 314. The second vent 312 is used to spray gas at a downward angle relative to the horizontal direction to generate downward gas flow pressure to resist the capillary climbing force of the molten solder along the surface of the pin 82, forming a gas-liquid tension balance surface at the soldering boundary of the pin 82. In addition, the air curtain mechanism 3 also includes a first preheater 34 and a second preheater 35 respectively disposed in the first cavity 313 and the second cavity. The first preheater 34 and the second preheater 35 can be ceramic heating elements or resistance heating elements, used to preheat the gas entering the cavity, raising the gas temperature to the range of 80℃~120℃, avoiding thermal stress damage caused by cold airflow directly impacting the pins. The arrangement of the first vent 311 and the second vent 312 allows the air curtain mechanism 3 to precisely control the direction and pressure of gas injection, thereby effectively preventing molten solder from climbing up and ensuring the accuracy of the soldering area.The working process of the air curtain mechanism 3 is as follows: the first gas injection component 32 pressurizes nitrogen and sends it into the first cavity 313. After being heated by the first preheater 34, it is horizontally ejected from the first vent 311, forming a protective atmosphere layer around the pins 82 and suppressing the oxygen content to below 0.1%. At the same time, the second gas injection component 33 pressurizes gas and sends it into the second cavity 314. After being heated by the second preheater 35, it is obliquely ejected from the second vent 312. Since there are only two rows of pins 82 in each row, the second vents 312 on both sides of the enclosure ring 31 directly spray airflow from both sides onto their respective rows of pins, immersing the pins 82 in molten solder. An annular air curtain is formed at the interface; its technical effect is that the horizontally sprayed protective gas isolates oxygen to prevent pin oxidation, while the dynamic pressure head generated by the downward-sloping high-speed airflow at the soldering boundary can effectively counteract the capillary upward force of the solder along the pin surface. Since the two rows of pins are directly covered by the second air outlet 312 on both sides, the airflow does not need to pass through other pin rows to reach the target pin surface, avoiding the problem of air pressure attenuation caused by multiple pin rows blocking. By adjusting the airflow pressure, the gas-liquid interface can be stably maintained at a predetermined height, thereby achieving precise local soldering depth control and preventing the solder from climbing and contaminating the connector body.

[0051] For details, please refer to Figure 1 The tin bath 9 is used to hold molten tin and maintain it in a molten state. The outer wall of the tin bath 9 is covered with an insulation layer, which can be made of aluminum silicate fiber felt or aerogel insulation material to reduce heat loss. The tin bath 9 is equipped with an electric heating element 91 for heating the molten tin and an in-tank thermocouple for monitoring the temperature of the molten tin. The electric heating element 91 is embedded in the bottom or side wall of the tin bath 9, and the temperature probe of the in-tank thermocouple extends into the molten tin. Both are electrically connected to the control unit 64 to achieve constant temperature control. The molten tin in the tin bath 9 is typically Sn63Pb37 eutectic solder or lead-free Sn-Ag-Cu alloy, with a melting point controlled between 183℃ and 220℃.

[0052] For details, please refer to Figure 1 The moving end 41 of the lifting drive module 4 is connected to the positioning base 11 and is used to drive the positioning base 11 and the connector 8 on it to move vertically. The lifting drive module 4 can be an electric screw jack, which has the characteristics of high precision and good stability. It can also be a linear module driven by a servo motor or a precision cylinder, which can achieve rapid lifting and precise positioning. The lifting drive module 4 immerses the pin 82 into the molten solder in the solder bath 9 according to a preset depth, and positions the second vent 312 at a preset height above the molten solder surface (usually maintained at 2mm to 5mm). This ensures that the pin 82 is soldered at a suitable depth, and the position of the second vent 312 can effectively play the role of an air curtain.

[0053] For details, please refer to Figure 1 and Figure 3 The system also includes a high-frequency micro-vibration module 7, which is mounted on the positioning base 11 (or integrated into the connection interface between the moving end 41 of the lifting drive module 4 and the positioning base 11). This module generates high-frequency vertical vibrations (frequency range 100Hz~500Hz, amplitude 0.05mm~0.2mm) during the process of the pin 82 detaching from the molten solder. The high-frequency micro-vibration module 7 can be a piezoelectric ceramic vibrator or an electromagnetic vibrator, with its vibration output shaft rigidly connected to the positioning base 11. The operation of the high-frequency micro-vibration module 7 is as follows: when the pin 82 completes its soldering preparation and rises to detach from the molten solder, the control unit 64 triggers the high-frequency micro-vibration module 7 to start, generating brief high-frequency pulse vibrations (duration 0.5s~2s). Its technical effect is to use high-frequency vibration to break the sticky wires between the tip of the pin 82 and the molten solder, avoiding the formation of solder beads or solder bridging defects, while simultaneously helping to shake off excess molten solder adhering to the pin surface, improving the appearance quality of the soldering.

[0054] For details, please refer to Figure 3 It also includes a water-cooling mechanism 5, which includes a water tank 51, a circulating pump 52, an inlet pipe 53, an outlet pipe 54, a return pipe 55, and a cooler 56. The water tank 51 contains deionized water or an ethylene glycol aqueous solution as a cooling medium. The cooler 56 is installed inside the water tank 51 (or connected in series with the return pipe 55) to continuously cool the cooling medium. The inlet of the circulating pump 52 is connected to the bottom of the water tank 51 via the inlet pipe 53, and the outlet of the circulating pump 52 is connected to the inlet interface 113 via the outlet pipe 54. One end of the return pipe 55 is connected to the outlet interface 114, and the other end of the return pipe 55 flows back to the upper part of the water tank 51. The working process of the water cooling mechanism 5 is as follows: the circulating pump 52 draws the low-temperature cooling medium from the water tank 51, and presses it into the heat dissipation channel 112 of the positioning base 11 through the water inlet pipe 53 and the water inlet interface 113, so as to remove the heat generated by the heating surface of the thermoelectric semiconductor element 21 and the process heat conducted from the positioning base 11. Then the high-temperature medium flows back to the water tank 51 through the water outlet interface 114 and the water return pipe 55, and is cooled by the cooler 56 and then circulated again. Its technical effect is to establish an efficient heat dissipation path, ensuring that the thermal management module 2 can continuously and stably maintain the low temperature state of the connector body 81, and prevent the temperature control failure caused by heat accumulation even under continuous operation conditions.

[0055] For details, please refer to Figure 1 and Figure 3The system also includes a detection and control component 6, which comprises a liquid level sensing unit 61, a temperature sensing unit 62, a mounting bracket 63, and a control unit 64. The liquid level sensing unit 61 is fixed to the side of the positioning base 11 (or to a fixed bracket above the solder bath 9) via the mounting bracket 63, and is used to detect the absolute liquid level of the molten solder in the solder bath 9 in real time. Non-contact measurement can be achieved using a laser displacement sensor or an ultrasonic level gauge. The temperature sensing unit 62 is fixed to the side of the positioning base 11 via the mounting bracket 63, and is used to detect the temperature of the molten solder in the solder bath 9 in real time (by reading thermocouple data in the bath or infrared temperature measurement) and the ambient temperature of the lead processing area (by thermocouples arranged near the enclosure ring 31). The control unit 64 is connected to the liquid level sensing unit 61, the temperature sensing unit 62, the lifting drive module 4, the first air valve 323 and the second air valve 332 of the air curtain mechanism 3, the electrical control terminal of the thermal management module 2, the electric heating element 91 of the solder bath 9, and the high-frequency micro-vibration module 7. The control unit 64 can be an industrial PLC controller or an embedded industrial computer. It is used to compensate the descent endpoint position of the lifting drive module 4 in real time based on the liquid level height data fed back by the liquid level sensing unit 61, and to adjust the airflow pressure of the second vent 312 (by controlling the opening of the second air valve 332 or the speed of the second air pump 331) based on the solder temperature data fed back by the temperature sensing unit 62. It also adaptively adjusts the cooling / heating output power of the thermal management module 2 based on the ambient temperature data of the pin processing area. The working process of this detection and control component 6 is as follows: the control unit 64 collects liquid level and temperature data at a frequency of not less than 10Hz, calculates the control quantity in real time using a built-in PID algorithm, and outputs it to each actuator. Its technical effect is to achieve closed-loop adaptive control of the tinning process parameters, automatically compensating for the influence of interference factors such as solder evaporation and ambient temperature fluctuations on the tinning quality, thereby improving process consistency and yield.

[0056] The overall operation of the device in this embodiment is as follows:

[0057] Please refer to Figures 1 to 4Before starting the device, process parameters (including soldering depth, solder temperature, immersion time, and air pressure parameters) are set via control unit 64. During operation, the connector 8 to be processed is first inserted into the positioning cavity of positioning base 11 and locked in place by fixing component 12; then the thermal management module 2 is activated, and thermoelectric semiconductor element 21 works to cool the connector body 81 to a preset temperature (e.g., below 40°C); at the same time, water cooling mechanism 5 is activated to establish cooling water circulation, the first gas injection component 32 and the second gas injection component 33 are activated, and the first preheater 34 and the second preheater 35 are turned on, so that preheated nitrogen gas is discharged from the first vent 311 to form a protective atmosphere, and preheated high-speed airflow is discharged from the second vent 312; then the electric heating element 91 of solder bath 9 is activated to heat the solder to a molten state and maintain a constant temperature. After preparation, the control unit 64 calculates the target descent position based on the real-time liquid level height detected by the liquid level sensing unit 61 and drives the lifting drive module 4 to lower the positioning base 11, allowing the pins 82 to slowly immerse in the molten solder along a predetermined trajectory. During immersion, the second vent 312 directly aligns with the two columns of pins of each row of pins 82 from both sides, continuously spraying downward-sloping airflow to form a gas-liquid tension balance surface at the base of the pins 82, preventing the molten solder from climbing upwards. After the set soldering time is reached, the control unit 64 triggers the high-frequency micro-vibration module 7 and simultaneously drives the lifting drive module 4 to move in the opposite direction, causing the pins 82 to quickly detach from the molten solder under the action of high-frequency micro-vibration. At this time, the airflow parameters of the second vent 312 automatically switch to the purging mode to remove residual molten solder between the pins. Finally, the thermal management module 2 forces the pins 82 to cool and solidify, and the connector 8 is unloaded, completing one soldering cycle. The entire process is fully automatically monitored by the control unit 64, which can dynamically correct the air pressure and temperature parameters based on the data fed back by the temperature sensing unit 62 to ensure stable and controllable soldering quality.

[0058] The implementation principle of this embodiment is as follows: the device accurately fixes the connector 8 through the clamping mechanism 1, the thermal management module 2 controls the temperature of the connector body 81, the air curtain mechanism 3 prevents the solder liquid from climbing up, the lifting drive module 4 controls the depth of the pins 82 immersed in the solder liquid, the high-frequency micro-vibration module 7 eliminates the wire pulling phenomenon during desoldering, the water cooling mechanism 5 ensures continuous heat dissipation, and the detection and control component 6 realizes closed-loop control of the entire process. All parts work together to achieve precise control of local desoldering of multi-row high-density pin connectors, avoiding the problems existing in traditional methods, improving processing efficiency and quality, and reducing costs and time. In particular, since the pins 82 of the connector 8 are arranged in a comb-like pattern of "multi-row × two columns", the second air outlets 312 on both sides of the enclosure ring 31 correspond one-to-one with the two columns of pins. The airflow directly acts on the outer surface of each column of pins from both sides, eliminating the problem that the airflow needs to penetrate multiple columns of pins to reach the inner pins. This fundamentally ensures the uniform coverage and effective control of the airflow pressure on the soldering boundary of each pin.

[0059] For the best option, please refer to the following: Figure 2 and Figure 3 The positioning base 11 also forms a heat dissipation channel 112, and the device also includes a water cooling mechanism 5. The water cooling mechanism 5 includes a water tank 51, a circulating pump 52, an inlet pipe 53, an outlet pipe 54, a return pipe 55, and a cooler 56. The heat dissipation channel 112 is provided with an inlet interface 113 and an outlet interface 114 at both ends. The inlet of the circulating pump 52 is connected to the water tank 51 via the inlet pipe 53, and the outlet of the circulating pump 52 is connected to the inlet interface 113 via the outlet pipe 54. One end of the return pipe 55 is connected to the outlet interface 114, and the other end of the return pipe 55 is connected to the water tank 51. The cooler 56 is set in the water tank 51 and is used to continuously cool the water in the water tank 51.

[0060] The water tank 51 can be made of plastic, which has good corrosion resistance, or stainless steel, which is more robust. The circulating pump 52 can be a centrifugal pump, which has the characteristics of large flow rate and high head, or other types of pumps can be used. The cooler 56 can be a compressor cooler, which has high cooling efficiency, or a semiconductor cooler, which is small in size and low in energy consumption. The water cooling mechanism 5 dissipates heat from the positioning base 11, which can further improve the thermal management effect, ensure that the connector 8 can be soldered in a stable temperature environment, reduce the impact of excessive temperature on the connector, and improve the processing quality and reliability.

[0061] In this embodiment, the water cooling mechanism 5 and the thermal management module 2 work together to remove the heat from the positioning base 11 through water circulation, which further enhances the temperature control capability of the connector body 81. This allows the device to maintain a stable temperature during long-term operation, improves the stability and reliability of the device, better solves the thermal management problem, and ensures the smooth progress of the tinning process.

[0062] For the best option, please refer to the following: Figure 2 The enclosure ring 31 has a first cavity 313 and a second cavity 314 that are independent of each other. The first air outlet 311 is connected to the first cavity 313 and the second air outlet 312 is connected to the second cavity 314. The air curtain mechanism 3 also includes a first preheater 34 and a second preheater 35 respectively disposed in the first cavity 313 and the second cavity.

[0063] The first preheater 34 and the second preheater 35 can be heated by resistance wire, which is simple in structure and highly efficient. Alternatively, ceramic heating elements can be used, which feature rapid heating and long lifespan. Preheating the gas using the first preheater 34 and the second preheater 35 increases the gas temperature, reducing the impact of low gas temperature on the pins 82 and the molten solder, thus improving the quality and effect of soldering. Simultaneously, the independent first cavity 313 and the second cavity 314 can control the gas parameters of the first vent 311 and the second vent 312 respectively, allowing for more precise control of the air curtain mechanism 3.

[0064] The implementation principle of this embodiment is as follows: the first preheater 34 and the second preheater 35 in the air curtain mechanism 3 preheat the gas, which can optimize the effect of the air curtain and improve the tinning quality. The independent cavity design makes the control of gas parameters more flexible, further enhances the ability of the air curtain mechanism 3 to prevent molten tin from climbing up, improves the performance of the air curtain mechanism 3, and thus better achieves precise control of the tinning area.

[0065] For the best option, please refer to the following: Figure 3 It also includes a liquid level sensing unit 61, a temperature sensing unit 62, and a control unit 64. The liquid level sensing unit 61 is fixed to the side of the positioning base 11 via a mounting bracket 63 and is used to detect the absolute liquid level height of the molten solder in real time. The temperature sensing unit 62 is fixed to the side of the positioning base 11 via a mounting bracket 63 and is used to detect the temperature of the molten solder and the ambient temperature of the pin processing area in real time. The control unit 64 is connected to the liquid level sensing unit 61, the temperature sensing unit 62, the lifting drive module 4, the air curtain mechanism 3, and the thermal management module 2 via signals. The control unit 64 is used to compensate the descent endpoint position of the lifting drive module 4 in real time based on the liquid level height data fed back by the liquid level sensing unit 61, adjust the airflow pressure of the second vent 312 based on the molten solder temperature data fed back by the temperature sensing unit 62, and adaptively adjust the cooling / heating output power of the thermal management module 2 based on the ambient temperature data of the pin processing area.

[0066] The liquid level sensing unit 61 can employ an ultrasonic liquid level sensor, which features high measurement accuracy and non-contact measurement; alternatively, it can use a capacitive liquid level sensor or a laser displacement sensor. The temperature sensing unit 62 can employ a thermocouple temperature sensor, offering a wide measurement range and high accuracy; alternatively, it can use a thermistor temperature sensor or an infrared thermometer. The control unit 64 can be a microcontroller, characterized by fast processing speed and low cost; or it can use a programmable logic controller (PLC), offering more powerful functions and higher reliability. By monitoring relevant data in real time through the liquid level sensing unit 61 and the temperature sensing unit 62, the control unit 64 precisely controls the lifting drive module 4, the air curtain mechanism 3, and the thermal management module 2 based on this data. This allows the device to automatically adjust parameters according to actual conditions, improving the automation level and processing accuracy of the device.

[0067] In this embodiment, the control unit 64 adjusts each module of the device in real time based on the data fed back by the liquid level sensing unit 61 and the temperature sensing unit 62, realizing intelligent control of the device. It can automatically compensate for the descent endpoint position of the lifting drive module 4 according to actual conditions, adjust the airflow pressure of the second air outlet 312 and the output power of the thermal management module 2, improving the adaptability and processing quality of the device, and enhancing its automation level and control accuracy.

[0068] Example 2

[0069] Please refer to Figures 1 to 4 The method for partial gold removal and soldering of multi-row high-density pin connectors provided in this application embodiment adopts the partial gold removal and soldering device for multi-row high-density pin connectors as described in Embodiment 1 above, and includes the following steps:

[0070] S1. Environment Setup: Insert connector 8 into positioning base 11 and lock it in place using fixing component 12. Activate thermoelectric semiconductor element 21. The cooling surface of thermoelectric semiconductor element 21 lowers the temperature of positioning base 11 to below a first preset temperature (e.g., 40°C). Simultaneously, activate the first gas injection component 32, the second gas injection component 33, the first preheater 34, and the second preheater 35. Hot air (approximately 100°C) is blown out from the first vent 311 and the second vent 312, raising the temperature of pin 82 to a second preset temperature (e.g., 80°C–120°C). Simultaneously, nitrogen gas discharged from the first vent 311 reduces the oxygen content in the processing area to below a preset concentration (e.g., 0.1%), establishing a protective atmosphere. After the temperature of positioning base 11 stabilizes below the first preset temperature and the oxygen content in the processing area drops below the preset concentration, proceed to the next step.

[0071] In this step, the first gas flow rate output from the first outlet 311 is... and the second gas flow rate output from the second outlet 312 The following relationship must be satisfied:

[0072]

[0073]

[0074] in, The cross-sectional area of ​​the through hole 111 inside the enclosure ring 31 is... For the extension length of pin 82, For the total volume of pin 82, The atmosphere replacement coefficient (values ​​range from 1.5 to 3). Set the preset rinsing time (e.g., 5s to 10s); It is the flow constant (related to the nozzle geometry). This is the surface tension coefficient of molten tin (approximately 0.5 N / m for Sn63Pb37). Contact angle, This refers to the spacing between adjacent pins 82. The technical advantage of the above formula is that it determines the optimal gas flow rate through theoretical calculation, ensuring sufficient replacement of oxygen in the processing area while avoiding excessive airflow that could disturb the surface of the molten solder.

[0075] The thermoelectric semiconductor element 21 can quickly reduce the temperature of the positioning base 11. The first gas injection assembly 32 and the second gas injection assembly 33 provide gas, and the first preheater 34 and the second preheater 35 heat the gas, thereby creating a suitable temperature and gas environment for the soldering operation. The nitrogen gas discharged from the first vent 311 can effectively prevent the pins 82 from oxidizing and ensure the quality of soldering.

[0076] S2, Servo Liquid Finding: The control unit 64 drives the lifting drive module 4 to immerse the pin 82 in the molten solder based on the data fed back by the liquid level sensing unit 61, and dynamically compensates for the descent endpoint position based on the real-time liquid level height.

[0077] In this step, the control unit 64 drives the lifting drive module 4 to drive the positioning base 11 to descend according to a segmented motion trajectory. The segmented motion trajectory includes: a first stage, when the positioning base 11 is more than a first preset distance (e.g., 20mm) from the molten solder surface, it descends rapidly at a first speed (e.g., 50mm / s); a second stage, when the positioning base 11 is within a second preset distance (e.g., 5mm to 20mm) from the molten solder surface, the speed of the positioning base 11 decreases from the first speed to the second speed (e.g., 5mm / s); a third stage, when the tip of the pin 82 is within a third preset distance (e.g., 0 to 5mm) from the molten solder surface, it descends slowly at a third speed (e.g., 1mm / s) until the pin 82 is submerged to a set depth; in the third stage, the control unit 64 compares the real-time liquid level data of the liquid level sensing unit 61 with the set immersion depth, and automatically compensates for the stop position of the positioning base 11 when the liquid level height deviates. The technical advantage of this segmented deceleration approach control strategy is that it ensures operational efficiency, avoids splashing caused by high-speed impact on molten solder, and ensures the accuracy of soldering depth through real-time liquid level compensation (the error can be controlled within ±0.1mm).

[0078] The control unit 64 precisely controls the movement of the lifting drive module 4 based on the feedback from the liquid level sensing unit 61, ensuring that the pin 82 can be accurately immersed in the molten solder, and adjusts the descent endpoint position in real time according to the change in liquid level, thereby improving the accuracy of soldering.

[0079] S3. Airflow obstruction: During the immersion of pin 82 in molten solder, the airflow pressure of the second vent 312 is adjusted. The second vent 312 on both sides of the confinement ring 31 sprays airflow directly at the two columns of pins of each row of pins 82 from both sides, generating a gas-liquid tension balance surface at the tinning boundary of pin 82 to block the molten solder from climbing up.

[0080] The control unit 64 acquires the molten solder temperature data fed back by the temperature sensing unit 62 in real time. And according to the formula Working air pressure of the second air outlet 312 Dynamic correction is performed, among which The reference pressure is (e.g., 0.3 MPa). This is the reference temperature for molten tin (e.g., 250℃). This is the compensation coefficient (e.g., 0.001 MPa / ℃). The physical meaning of this formula is that an increase in molten solder temperature leads to a decrease in surface tension coefficient and viscosity, thereby enhancing capillary climb ability. Therefore, a corresponding increase in gas pressure is needed to maintain the equilibrium position of the gas-liquid interface; conversely, a decrease in temperature leads to a decrease in viscosity. Through this temperature-based feedforward compensation control, the influence of molten solder temperature fluctuations on the tinning boundary position can be effectively eliminated, ensuring the consistency of the tinning height. Dynamically adjusting the gas pressure better resists the capillary climb force of the molten solder, ensuring the accuracy of the tinning area.

[0081] It should be noted that the pins 82 of connector 8 are arranged in a comb-like pattern of "multiple rows × two columns" (e.g., Figure 4 As shown, there is no obstruction from other pin rows between the second vent 312 on each side of the enclosure ring 31 and the corresponding column of pins. Therefore, the airflow ejected from the second vent 312 can directly reach the pin surface with complete dynamic pressure, forming an effective gas-liquid tension balance surface at the tinning boundary. This is fundamentally different from the case where the pins are densely arranged in multiple rows (such as 4 rows, 6 rows, etc.) – in the case of multiple rows, the outer row of pins will have an obstruction effect on the airflow, resulting in a severe attenuation of the airflow pressure at the inner row of pins, thus failing to effectively resist capillary climbing force. The technical solution of this application is designed based on the actual arrangement characteristics of such connector pins of "multiple rows × two columns", ensuring uniform and effective coverage of each pin by the airflow pressure.

[0082] S4, Vibration Desoldering: After the set soldering time (e.g., 2s to 5s) is reached, the control unit 64 drives the lifting drive module 4 to lift the positioning base 11 and pin 82 to detach from the solder liquid, triggering the high-frequency micro-vibration module 7 to eliminate sticky wires, and adjusts the spray parameters of the second air outlet 312 (e.g., increase the flow rate, adjust the spray angle) to blow away the gap between adjacent pins 82.

[0083] The high-frequency micro-vibration module 7 can generate high-frequency vibration in the vertical direction (frequency 200Hz, amplitude 0.1mm), effectively breaking the sticky wires between the tip of pin 82 and the molten solder. The vibration time is controlled within 0.5s to 1s after the tip of pin 82 leaves the molten solder surface. The spray parameters of the second vent 312 can be adjusted to remove molten solder from the gaps between adjacent pins 82, ensuring the cleanliness of pins 82. The technical effect of this step is that it solves the defects such as "tear-like" and "bridging" commonly found in traditional desoldering processes, and improves the appearance quality and electrical reliability of soldering.

[0084] S5. Cooling and unloading: The tin layer of pin 82 is cooled by the thermal management module 2 (forced to cool to below 100°C to completely solidify the tin layer), and then the fixing component 12 is released to unload connector 8.

[0085] The thermal management module 2 can quickly reduce the temperature of the solder layer on pin 82, allowing the solder layer to solidify, and then the connector 8 can be unloaded from the positioning base 11, completing the entire soldering process. Optionally, after unloading, a visual inspection system can automatically judge the soldering quality, and defective products will automatically enter the rework process.

[0086] The implementation principle of this embodiment is as follows: This method, through a series of steps, from environment setup to final cooling and unloading, with each step working in close coordination, achieves precise control over the localized de-golding and soldering of multi-row high-density pin connectors. By real-time monitoring and dynamic parameter adjustment, the quality and precision of soldering are ensured, and processing efficiency is improved.

[0087] The specific embodiments described above do not constitute a limitation on the scope of protection of this application. Any other corresponding changes and modifications made based on the technical concept of this application should be included within the scope of protection of this application.

Claims

1. A device for partial de-goldening and desoldering of multi-row high-density pin connectors, characterized in that, include: The clamping mechanism (1) includes a positioning base (11) and a fixing component (12). The positioning base (11) has a positioning cavity that matches the outline of the body (81) of the connector (8). The lower end face of the positioning base (11) has a through hole (111) that communicates with the positioning cavity. The positioning cavity is used to accommodate the body (81) of the connector (8) and to allow the multiple rows of pins (82) of the connector (8) to extend vertically downward from the through hole (111). The multiple rows of pins (82) are arranged in multiple rows along the arrangement direction, and each row of pins (82) contains only two columns. The fixing component (12) is detachably connected to the positioning base (11) and is used to fix the connector (8) in the positioning cavity. The thermal management module (2) includes a thermoelectric semiconductor element (21) disposed in the positioning base (11), the cooling surface of the thermoelectric semiconductor element (21) facing the positioning cavity, for controlling the temperature of the body (81) of the connector (8); An air curtain mechanism (3) includes a barrier ring (31), a first air injection component (32), and a second air injection component (33). The barrier ring (31) is fixed to the lower end face of the positioning base (11) and surrounds the radial outer side of the through hole (111). The inner wall of the barrier ring (31) is provided with a plurality of first air outlet holes (311) and a plurality of second air outlet holes (312) located below the first air outlet holes (311). The second air outlet holes (312) are distributed on the inner walls of opposite sides of the barrier ring (31) along the arrangement direction of the pins (82). The number of second air outlet holes (312) on each side corresponds to the number of rows of the multiple rows of pins (82), so that each second air outlet hole (312) on each side... 2) Align with the adjacent column of pins in a row of pins (82), so that the second vents (312) on both sides of the confining ring (31) correspond to the two columns of pins in each row of pins (82), and the airflow acts directly on the surface of each column of pins from both sides. The first gas injection component (32) is used to supply inert gas to the first vent (311), and the second gas injection component (33) is used to supply gas to the second vent (312). The second vent (312) is used to spray gas at an angle that is inclined downward relative to the horizontal direction to generate downward air pressure to resist the capillary climbing force of the molten solder along the surface of the pin (82), and form a gas-liquid tension balance surface at the tinning boundary of the pin (82). A tin bath (9) is used to hold molten tin and maintain the molten tin in a molten state; The lifting drive module (4) has its moving end (41) connected to the positioning base (11) for driving the positioning base (11) and the connector (8) on it to move up and down in the vertical direction. The lifting drive module (4) immerses the pin (82) into the molten solder in the solder bath (9) according to a preset depth, and makes the second vent (312) located at a preset height above the molten solder surface.

2. The device for partial de-goldening and desoldering of a multi-row high-density pin connector according to claim 1, characterized in that, The positioning base (11) also forms a heat dissipation channel (112). The multi-row high-density pin connector partial gold removal and tinning device also includes a water cooling mechanism (5). The water cooling mechanism (5) includes a water tank (51), a circulating pump (52), an inlet pipe (53), an outlet pipe (54), a return pipe (55), and a cooler (56). The heat dissipation channel (112) is provided with an inlet interface (113) and an outlet interface (114) at both ends. The circulating pump (52) The inlet of the circulating pump (52) is connected to the water tank (51) via the inlet pipe (53), the outlet of the circulating pump (52) is connected to the inlet interface (113) via the outlet pipe (54), one end of the return pipe (55) is connected to the outlet interface (114), and the other end of the return pipe (55) is connected to the water tank (51). The cooler (56) is installed in the water tank (51) and is used to continuously cool the water in the water tank (51). The outer wall of the tin bath (9) is covered with a heat insulation layer, and the tin bath (9) is provided with an electric heating element (91) for heating the molten tin and a thermocouple for monitoring the temperature of the molten tin.

3. The device for partial gold removal and tinning of multi-row high-density pin connectors according to claim 2, characterized in that, The enclosure ring (31) has a first cavity (313) and a second cavity (314) that are independent of each other. The first air outlet (311) is connected to the first cavity (313), and the second air outlet (312) is connected to the second cavity (314). The air curtain mechanism (3) also includes a first preheater (34) and a second preheater (35) respectively disposed in the first cavity (313) and the second cavity (314).

4. The device for partial de-goldening and desoldering of multi-row high-density pin connectors according to claim 1, characterized in that, The first air outlet (311) sprays in a horizontal direction, and the second air outlet (312) sprays at an angle of 30° to 45° with the horizontal direction; both the first air outlet (311) and the second air outlet (312) are matrix micropore structures distributed along the pin (82) arrangement direction. The side wall of the enclosure ring (31) is provided with a first air inlet (315) and a second air inlet (316) that are respectively connected to the first cavity (313) and the second cavity (314); The first gas injection assembly (32) includes a first gas pump (321), a first nitrogen cylinder (322), a first gas valve (323), and a first gas delivery hose (324). The inlet of the first gas pump (321) is connected to the first nitrogen cylinder (322), and the outlet of the first gas pump (321) is connected to one end of the first gas delivery hose (324) via the first gas valve (323). The other end of the first gas delivery hose (324) is connected to the first air inlet (315). The second air injection assembly (33) includes a second air pump (331), a second air valve (332) and a second air delivery hose (333). The outlet of the second air pump (331) is connected to one end of the second air delivery hose (333) via the second air valve (332), and the other end of the second air delivery hose (333) is connected to the second air inlet (316).

5. The device for partial de-goldening and desoldering of a multi-row high-density pin connector according to claim 1, characterized in that, Also includes: The liquid level sensing unit (61) is fixed to the side of the positioning base (11) by the mounting bracket (63) and is used to detect the absolute liquid level height of the molten tin in the tin bath (9) in real time. The temperature sensing unit (62) is fixed to the side of the positioning base (11) by the mounting bracket (63) and is used to detect the temperature of the molten solder in the solder bath (9) and the ambient temperature of the pin (82) processing area in real time. The control unit (64) is connected to the liquid level sensing unit (61), the temperature sensing unit (62), the lifting drive module (4), the air curtain mechanism (3), the thermal management module (2), and the electric heating element (91) of the solder bath (9). The control unit (64) is used to compensate the descent endpoint position of the lifting drive module (4) in real time according to the liquid level height data fed back by the liquid level sensing unit (61), adjust the airflow pressure of the second air outlet (312) according to the solder temperature data fed back by the temperature sensing unit (62), and adaptively adjust the cooling / heating output power of the thermal management module (2) according to the ambient temperature data of the pin (82) processing area.

6. The device for partial gold removal and tinning of a multi-row high-density pin connector according to claim 1, characterized in that, It also includes a high-frequency micro-vibration module (7) installed on the positioning base (11), which is used to generate high-frequency vibration in the vertical direction during the process of the pin (82) leaving the molten solder, so as to break the sticky wire between the tip of the pin (82) and the molten solder.

7. A method for partial gold removal and soldering of a multi-row high-density pin connector, characterized in that, The device for partial de-gold plating of a multi-row high-density pin connector as described in claim 5 includes the following steps: S1. Environment Setup: Insert the connector (8) into the positioning base (11) and lock it in place with the fixing component (12). Start the thermoelectric semiconductor element (21). The cooling surface of the thermoelectric semiconductor element (21) lowers the temperature of the positioning base (11) to below the first preset temperature. At the same time, start the first gas injection component (32), the second gas injection component (33), the first preheater (34), and the second preheater (35). Hot air is blown out from the first vent (311) and the second vent (312) to raise the temperature of the pin (82) to the second preset temperature. Meanwhile, the nitrogen gas discharged from the first vent (311) lowers the oxygen content in the processing area to below the preset concentration, establishing a protective atmosphere. After the temperature of the positioning base (11) stabilizes below the first preset temperature and the oxygen content in the processing area drops below the preset concentration, proceed to the next step. S2, Servo Liquid Search: The control unit (64) drives the lifting drive module (4) to immerse the pin (82) into the molten solder in the molten solder bath (9) according to the data fed back by the liquid level sensing unit (61), and dynamically compensates the descent endpoint position according to the real-time liquid level height. S3, airflow obstruction: During the immersion of the pin (82) into the solder bath (9), the airflow pressure of the second vent (312) is adjusted, and the second vent (312) on both sides of the baffle ring (31) sprays airflow directly from both sides to the two columns of pins of each row of pins (82), generating a gas-liquid tension balance surface at the soldering boundary of the pin (82) to block the solder from climbing up. S4, Vibration Desoldering: After the set soldering time is reached, when the control unit (64) drives the lifting drive module (4) to lift the positioning base (11) and its pins (82) to rise and detach from the solder liquid, the high-frequency micro-vibration module (7) is triggered to eliminate sticky wires and adjust the spraying parameters of the second air outlet (312) to blow away the gap between adjacent pins (82). S5. Cooling and unloading: The tin layer of the pin (82) is cooled by the thermal management module (2), and then the connector (8) is unloaded.

8. The method for partial de-gold plating of a multi-row high-density pin connector according to claim 7, characterized in that, In step S3, the control unit (64) acquires the molten tin temperature data fed back by the temperature sensing unit (62) in real time. And according to the formula Working air pressure of the second air outlet (312) Dynamic correction is performed, among which... As the reference pressure, The reference temperature for molten tin. This is the compensation coefficient.

9. The method for partial de-gold plating of a multi-row high-density pin connector according to claim 7, characterized in that, In step S1, the first gas flow rate output from the first outlet (311) is... and the second gas flow rate output from the second outlet (312) The following relationship must be satisfied: ， ， in, The cross-sectional area of ​​the through hole (111) inside the enclosure ring (31) is... The extension length of pin (82) The total volume of pins (82) is The atmosphere replacement coefficient is... Preset rinsing time; For flow rate constant, The surface tension coefficient of molten tin. Contact angle, The spacing between adjacent pins (82).

10. The method for partial de-gold plating of a multi-row high-density pin connector according to claim 7, characterized in that, The control unit (64) drives the lifting drive module (4) to lower the positioning base (11) according to a segmented motion trajectory, the segmented motion trajectory including: In the first stage, when the positioning base (11) is more than a first preset distance from the molten tin surface, it descends at a first speed; In the second stage, when the positioning base (11) is within a second preset distance from the molten tin surface, the speed of the positioning base (11) decreases from the first speed to the second speed. In the third stage, when the tip of the pin (82) is within a third preset distance from the surface of the molten solder, it descends at a third speed until the pin (82) is submerged to a set depth. In the third stage, the control unit (64) compares the real-time liquid level data of the liquid level sensing unit (61) with the set immersion depth, and automatically compensates the stop position of the positioning base (11) when the liquid level height deviates.

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