Selective wave soldering tin connection prevention method for electric connector
By installing tin-collecting parts at the pads of the close-distance electrical connector and filling the solder with wave solder, the problem of short-circuiting tin during the soldering process is solved, and high-quality soldering effect is achieved.
Patent Information
- Application Number
- CN202411744335.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-30
- Publication Date
- 2025-04-29
AI Technical Summary
During selective wave soldering, the solder joints and pin spacing of the densely spaced electrical connectors are small, making it difficult for solder to disengage from the end pins of the device, which can easily cause short circuits of the tin connection and affect the solder quality.
Install specific tin-collecting parts at the end of the electrical connector pin to provide a release path for excess solder, use wave soldering technology to spray out liquid solder and fill through holes through capillary action to form a stable connection. The tin collecting parts adsorbs the excess solder after soldering to prevent tin connection.
It effectively prevents tin short circuit during the welding of the densely spaced electrical connector, improves the welding quality and efficiency, and ensures a stable connection of the device.
Smart Images
Figure CN119907197A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of PCB circuit board electronic assembly, and in particular to a method for preventing tin bridging by selective wave soldering of an electric connector. Background Art
[0002] In the process of assembling plug-in components on PCB, wave soldering technology has the advantages of high production efficiency, large output, and high degree of automation. All through-hole devices on traditional wave soldering PCB boards use the same soldering procedure, and all solder joints are soldered under the same parameters, which cannot be optimized for the device. In addition, the entire printed board passes through the liquid solder pool, which is prone to deformation due to excessive thermal shock, making it difficult to meet the soldering requirements of high-quality circuit boards. Selective wave soldering can solder the pins of each component on the circuit board according to the specified path, method and specific process parameters for different PCBs and their solder joint distribution and solder joint characteristics, and its welding heat input is small, so it has been widely used.
[0003] As electronic products continue to develop towards miniaturization and integration, the assembly density of PCB components is getting higher and higher. At the same time, in order to achieve high integration and miniaturization of PCB, a large number of new micro-rectangular fine-pitch electrical connectors are used, resulting in smaller and smaller solder joints and pin spacing of through-hole devices. This type of electrical connector is characterized by dense spacing and many leads. The pin spacing of a large number of connectors is only 1.27mm. In the process of selective wave soldering, in order to improve the welding efficiency, this type of electrical connector mostly uses the drag soldering method. During the process of collecting tin after the connector soldering, it is often difficult for the solder to detach from the end pin of the device, resulting in a short circuit between the pins and the tin, affecting the welding quality. Summary of the invention
[0004] In view of this, the present invention provides a selective wave soldering method for preventing bridging of tin in electrical connectors, which can achieve selective wave soldering method for preventing bridging of tin in electrical connectors with fine pitches.
[0005] To achieve the above purpose, the technical solution of the present invention is as follows:
[0006] A method for preventing bridging tin during selective wave soldering of an electrical connector comprises installing a tin collecting part of a specific specification at a specific distance and position corresponding to a pad at the end of an electrical connector pin, so as to provide a release path for excess solder; wherein, if the electrical connector is inserted on a PCB board, the tin collecting part is fixed on the PCB board; selective wave soldering sprays liquid solder from a nozzle in the form of a wave crest, and the solder contacts with the device pins and through holes and forms solder joints after cooling; the tin collecting part absorbs excess solder in the tin collecting process after soldering.
[0007] Among them, when selecting the wave soldering process, the nozzle and the pin are fixed at a vertical distance, and the wave crest contacts the electrical connector pin as the nozzle moves. The solder in the wave crest contacts the pin and the through-hole and fills the through-hole through capillary action, so that the device pin and the through-hole form a stable connection through the solder.
[0008] The wave crest moves from the pin at the front end of the electrical connector to the rear end as the nozzle moves, and the solder follows the wave crest and the pin and through-hole. When the wave crest moves to the next pin, a solder joint is formed at the root of the original pin, and excess solder detaches from the original pin as the wave crest moves.
[0009] Among them, when the wave crest moves to the end pin of the device, it remains in a moving state until the tin-collecting part is installed; the tin-collecting part absorbs the excess solder on the end pin of the device; the wave crest stays at the tin-collecting part position for a certain period of time and then withdraws to ensure that the tin is completely collected and the device welding is completed.
[0010] Among them, for electrical connector devices with a solder joint spacing of 1.27 mm or less on a printed circuit board, the specific implementation steps of the method are as follows:
[0011] Design the matching tin-collecting part size according to the size of the electrical connector, and install the tin-collecting part on the end pin of the electrical connector;
[0012] Set and select wave soldering equipment parameters, determine the solder pot temperature and tin pressing height according to PCB characteristics and electrical connector lead length; compile and select wave soldering program, determine the nozzle movement path, and ensure that the pin on the side of the tinned part is the last position passed by the wave crest;
[0013] Protect the non-welding position, and then select the wave soldering operation;
[0014] After soldering is completed, remove the PCB protection and tin-collecting parts;
[0015] Clean the PCB, clean the tinned parts and store them in categories.
[0016] Beneficial effects:
[0017] 1. The method of the present invention realizes selective wave soldering and anti-tinning of dense-pitch electrical connectors by adding a tin-collecting part to the pad of the PCB electrical connector. Specifically, a tin-collecting part of a specific specification is installed at a specific distance and position corresponding to the pad at the end of the electrical connector pin to provide a release path for excess solder. The electrical connector is plugged into the PCB board, and the tin-collecting part is fixed on the PCB board. Selective wave soldering sprays liquid solder from the nozzle in the form of a wave crest, and the solder contacts the device pins and through holes and forms solder joints after cooling. The tin-collecting part can absorb excess solder in the tin-collecting process after soldering.
[0018] 2. In the method of the present invention, during the wave soldering process, the nozzle and the pin are fixed at a vertical distance, and the wave crest contacts the pin of the electrical connector as the nozzle moves. The solder in the wave crest contacts the pin and the through-hole and fills the through-hole through capillary action, so that the device pin and the through-hole form a stable connection through the solder.
[0019] 3. In the method of the present invention, the wave crest moves from the pin at the front end of the electrical connector to the rear end as the nozzle moves, and the solder follows the wave crest and the pin and through hole. When the wave crest moves to the next pin, a solder joint is formed at the root of the original pin, and excess solder detaches from the original pin as the wave crest moves.
[0020] 4. In the method of the present invention, when the wave crest moves to the end pin of the device, it remains in a moving state until the tin collecting part is installed. The tin collecting part absorbs the excess solder on the end pin of the device, thereby preventing bridging. The wave crest stays at the tin collecting part position for a certain period of time and then withdraws, ensuring that the tin is completely collected and the device is soldered. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 The figure is a schematic diagram of the tin-collecting parts added to the soldering pad of the PCB electrical connector according to the present invention.
[0022] Figure 2 It is a schematic diagram of the contact between the wave crest and the pin in the present invention.
[0023] Figure 3 It is a schematic diagram of the wave soldering process in the present invention.
[0024] Figure 4 It is a schematic diagram of the process of absorbing excess solder by the tin collecting part in the present invention.
[0025] Figure 5 It is a schematic diagram of the pasting position of the tin-collecting parts in the present invention.
[0026] Figure 6 This is a schematic diagram of the nozzle movement path specified in the present invention. DETAILED DESCRIPTION
[0027] The present invention is described in detail below with reference to the accompanying drawings and embodiments.
[0028] The present invention proposes a method for preventing tin bridging during selective wave soldering of electrical connectors, which is achieved by adding a tin collecting part to the soldering pad of the PCB electrical connector, and is suitable for selective wave soldering of dense pitch electrical connectors. Specifically, a tin collecting part of a specific specification is installed at a specific distance and position corresponding to the soldering pad at the end of the electrical connector pin, providing a release path for excess solder. The tin collecting part added to the soldering pad of the PCB electrical connector of the present invention is as follows: Figure 1As shown, the electrical connector is inserted into the PCB board, and the tin collecting part is fixed on the PCB board. Selective wave soldering sprays liquid solder from the nozzle in the form of a wave crest, and the solder contacts the device pins and through holes and forms solder joints after cooling. The tin collecting part can absorb the excess solder in the tin collecting process after soldering.
[0029] In the process of wave soldering, the nozzle and the pin are fixed at a vertical distance, and the wave crest contacts the pin of the electrical connector as the nozzle moves. The solder in the wave crest contacts the pin and the through hole and fills the through hole through capillary action, so that the device pin and the through hole form a stable connection through the solder. Figure 2 As shown, the wave soldering process is as follows Figure 3 As shown, the wave crest moves from the pin at the front end of the electrical connector to the rear end as the nozzle moves, and the solder follows the wave crest to the pin and through-hole. When the wave crest moves to the next pin, a solder joint is formed at the root of the original pin, and the excess solder detaches from the original pin as the wave crest moves.
[0030] When the wave crest moves to the end pin of the device, it remains in the moving state until the tin collecting part is installed. The tin collecting part absorbs the excess solder on the end pin of the device, thereby preventing bridging. The wave crest stays at the tin collecting part for a certain period of time and then withdraws to ensure that the tin is completely collected and the device is soldered. The process of the tin collecting part absorbing excess solder is as follows Figure 4 shown.
[0031] Taking an electrical connector device with a solder joint spacing of 1.27 mm or less on a printed circuit board as an example, the method of the present invention is described, and the specific implementation steps are as follows:
[0032] Design the matching tin-collecting part size according to the size of the electrical connector, and install the tin-collecting part on the end pin of the electrical connector, such as Figure 5 As shown in the red box.
[0033] Set and select wave soldering equipment parameters, formulate parameters such as tin pot temperature and tin pressing height according to factors such as PCB characteristics and electrical connector lead length; compile and select wave soldering program and determine the nozzle movement path, such as Figure 6 As shown, start soldering from point 1, and move the nozzle in the direction of the black arrow, making sure that the pin on the side of the tinned part is the last position passed by the wave crest.
[0034] Protect the non-soldering positions and then select the wave soldering operation.
[0035] After soldering is completed, remove the PCB protection and tin-collecting parts.
[0036] Clean the PCB, clean the tinned parts and store them in categories.
[0037] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A method for preventing bridging tin in selective wave soldering of an electrical connector, characterized in that: A tin-collecting part of specific specifications is installed at a specific distance and position corresponding to the pad at the end of the electrical connector pin to provide a release path for excess solder; wherein, if the electrical connector is inserted into a PCB board, the tin-collecting part is fixed on the PCB board; selective wave soldering sprays liquid solder from a nozzle in the form of a wave crest, and the solder contacts the device pins and through-holes and forms solder joints after cooling; the tin-collecting part absorbs excess solder in the tin-collecting process after soldering.
2. The method according to claim 1, characterized in that When wave soldering is selected, the nozzle is at a fixed vertical distance from the pin, and the wave crest contacts the electrical connector pin as the nozzle moves. The solder in the wave crest contacts the pin and the through-hole and fills the through-hole through capillary action, so that the device pin and the through-hole form a stable connection through the solder.
3. The method according to claim 2, characterized in that The wave crest moves from the pin at the front end of the electrical connector to the end as the nozzle moves. The solder follows the wave crest and the pin and through-hole. When the wave crest moves to the next pin, a solder joint is formed at the root of the original pin, and the excess solder detaches from the original pin as the wave crest moves.
4. The method according to claim 1 or 2, characterized in that When the wave crest moves to the end pin of the device, it remains in a moving state until the tin-collecting part is installed; the tin-collecting part absorbs the excess solder on the end pin of the device; the wave crest stays at the tin-collecting part position for a certain period of time and then withdraws to ensure that the tin is completely collected and the device welding is completed.
5. The method according to claim 4, characterized in that For electrical connector devices with solder joint spacing of 1.27 mm or less on a printed circuit board, the method is specifically implemented in the following steps: Design the matching tin-collecting part size according to the size of the electrical connector, and install the tin-collecting part on the end pin of the electrical connector; Set and select wave soldering equipment parameters, and determine the solder pot temperature and solder pressing height according to PCB characteristics and electrical connector lead length; Prepare and select the wave soldering program, determine the nozzle movement path, and ensure that the pin on the side of the tinned part is the last position passed by the wave crest; Protect the non-welding position, and then select the wave soldering operation; After soldering is completed, remove the PCB protection and tin-collecting parts; Clean the PCB, clean the tinned parts and store them in categories.