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CN-122007528-A - Capacitive screen circuit welding device

CN122007528ACN 122007528 ACN122007528 ACN 122007528ACN-122007528-A

Abstract

The invention is suitable for the technical field of electronic manufacturing processes, and provides a capacitive screen circuit welding device which comprises a regulating and controlling system, wherein the regulating and controlling system comprises a turbulence wave self-adaptive regulating and controlling module, a laminar wave intensity regulating and controlling module and a control module, wherein the turbulence wave self-adaptive regulating and controlling module is used for constructing a turbulence wave self-adaptive regulating and controlling model based on a welding quality prediction index, preset turbulence wave intensity and a bridging rate detected after a front piece of PCB is welded, outputting target turbulence wave intensity and adjusting in the welding process of the next piece of the same product, and the laminar wave intensity regulating and controlling module is used for outputting target laminar wave intensity and adjusting in the welding process of the next piece of the same product. The capacitive screen circuit welding device provided by the invention can realize real-time and comprehensive monitoring, prediction and self-adaptive adjustment of the welding process.

Inventors

  • LIANG JIECHANG

Assignees

  • 广州市尼古拉触控科技有限公司

Dates

Publication Date
20260512
Application Date
20260305

Claims (7)

  1. 1. The utility model provides a electric capacity screen circuit welding set, includes welding bench (1), be provided with on welding bench (1) and be used for carrying out conveyer (2) of conveying to the PCB, conveyer (2) outside is provided with protection casing (4), be provided with in protection casing (4) and be used for preheating the heating system and to PCB welded welding equipment to the PCB, protection casing (4) one side is provided with scaling powder sprayer (3), its characterized in that still includes regulation and control system, and it includes: The pretreatment state evaluation module is used for constructing a pretreatment state evaluation model based on the actual measurement of the preheating temperature of the PCB surface, the standard reaching rate of an actual measurement temperature curve of a preheating zone, and the deviation between a flux spray quantity set value and a flowmeter feedback value, and outputting a pretreatment state index; The process treatment state evaluation module is used for constructing a process treatment state evaluation model based on the temperature stability of the tin bath, the real-time reading of the peak height sensor and the content of the solder oxide, and outputting a process treatment state index; the PCB welding quality prediction module is used for constructing a PCB welding quality prediction model based on the element layout density, the PCB thickness/aperture ratio, the transmission speed, the pretreatment state index and the process treatment state index and outputting a welding quality prediction index; The turbulence wave self-adaptive regulation and control module is used for constructing a turbulence wave self-adaptive regulation and control model based on a welding quality prediction index, preset turbulence wave intensity and a bridge rate detection after welding of a front block of PCB, outputting target turbulence wave intensity and regulating in the welding process of the next same product; and the laminar flow wave intensity regulation and control module is used for outputting the target laminar flow wave intensity and regulating the welding process of the next same product.
  2. 2. The capacitive screen circuit welding apparatus according to claim 1, wherein in the preprocessing state estimation model, the preprocessing state index is output by: Multiplying the normalized preheating temperature index, the measured temperature curve standard reaching rate of the preheating zone and the exponential decay function output value taking the absolute value of the relative deviation of the flux spraying amount as a variable respectively by corresponding preset positive number influence coefficients and summing the values, inputting the sum as a variable into an S-shaped exponential function for calculation, and mapping the output result to a [ -1,1] interval to obtain the pretreatment state index, wherein the sum of the influence coefficients is 1; The preheating temperature index is calculated by substituting the actually measured preheating temperature of the PCB surface into a maximum-minimum value normalization formula; the standard reaching rate of the measured temperature curve of the preheating zone is calculated by dividing the standard reaching temperature measuring point by the ratio of the total temperature measuring point; The relative flux spray amount deviation index is calculated by dividing the deviation value of the set flux spray amount and the actually measured flux spray amount by the set flux spray amount.
  3. 3. The capacitive screen circuit welding apparatus of claim 1, wherein in the process state evaluation model, the process state index is output by: performing first index operation by taking the reciprocal of the sum of the tin bath temperature fluctuation coefficient and 1 as a base, performing second index operation by taking the peak height index as a base, performing third index operation by taking (1 minus the solder oxide content index) as a base, and multiplying the three results to obtain a process state index, wherein the first index, the second index and the third index are respectively corresponding positive number sensitivity coefficients; The temperature fluctuation coefficient of the tin bath is obtained by dividing the standard deviation of the temperature in the sampling period by the standard deviation of the allowable maximum temperature; The peak height index is obtained by dividing the measured peak height by the calibrated maximum peak height; the solder oxide content index is obtained by dividing the measured solder oxide content by the allowable upper limit of the solder oxide content.
  4. 4. The capacitive screen circuit soldering apparatus according to claim 1, wherein in the PCB soldering quality prediction model, a soldering quality prediction index is outputted by: firstly, carrying out linear transformation on a pretreatment state index, multiplying the pretreatment state index by a process treatment state index, and dividing the pretreatment state index by a natural logarithmic function taking the product of an element layout density index and a plate thickness/aperture ratio index as a true number, wherein the obtained result is added with a natural constant e; finally, multiplying the obtained result by an exponential decay function taking the absolute value of the transmission speed deviating from a preset optimal threshold value as a variable to obtain a welding quality prediction index; the element layout density index is obtained by dividing the actual element layout density by the design allowable maximum density, and the actual element layout density is obtained by dividing the PCB pin number by the board area; The plate thickness/aperture ratio index is obtained by dividing the measured plate thickness/aperture ratio by the process allowable maximum ratio; the transfer rate index is obtained by dividing the measured PCB transfer rate by the transfer rate allowable upper limit.
  5. 5. The capacitive screen circuit welding apparatus of claim 1, wherein the turbulence wave adaptive regulation model outputs the target turbulence wave intensity by: Based on a preset turbulence wave intensity index, superposing a negative regulation term determined by a welding quality prediction index, and subtracting a positive penalty term determined by the bridging rate of the previous PCB to obtain a target turbulence wave intensity index; The preset turbulence wave intensity index is obtained by dividing the preset turbulence wave intensity value by the maximum turbulence wave intensity value allowed by the device; the bridging rate of the previous PCB is obtained by dividing the number of bridging welding spots of the previous PCB by the total number of welding spots.
  6. 6. The capacitive screen circuit welding device according to claim 1, wherein in the laminar wave intensity regulation module, the laminar wave intensity regulation model is constructed based on a welding quality prediction index, a real-time turbulence wave intensity, a solder real-time temperature, and a front piece of PCB solder filling degree.
  7. 7. The capacitive screen circuit welding apparatus according to claim 6, wherein in the laminar wave intensity regulation model, the target laminar wave intensity is output by: Multiplying the welding quality prediction index, an amplification factor related to the temperature deviation of the welding flux and the filling degree of the welding flux of the front PCB, and dividing the multiplied welding quality prediction index by the sum of the real-time turbulence wave intensity index and a small constant for preventing zero removal to obtain a target laminar wave intensity index; the solder temperature deviation index is obtained by subtracting the difference value of the solder standard temperature from the solder real-time temperature and dividing the solder standard temperature; the real-time turbulence wave intensity index is obtained by dividing the measured turbulence wave intensity value by the maximum turbulence wave intensity value allowed by the device.

Description

Capacitive screen circuit welding device Technical Field The invention belongs to the technical field of electronic manufacturing processes, and particularly relates to a capacitive screen circuit welding device. Background In the manufacturing process of the capacitive screen PCB, the wave soldering technology takes on the task of mass connection of the through hole component and part of the surface mount component, and the apparatus generally includes a conveying mechanism, a preheating unit, a soldering flux spraying system, a melting solder tank and other core components. However, conventional wave soldering equipment faces multiple technical bottlenecks for the special physical characteristics of the capacitive screen-specific PCB: Firstly, the thickness of a substrate is generally smaller than 0.8 mm, if the temperature distribution is uneven or the gradient exceeds the process tolerance in the preheating stage, the soldering flux is insufficiently activated to cause cold welding, cold welding or thermal deformation of a substrate, secondly, a soldering flux spraying system adopts an open loop control mode, the board type characteristics and the production takt variation of PCBs with different sizes cannot be dynamically adapted to cause overlarge fluctuation of spraying quantity to influence the solder wetting uniformity and the oxide removal effect, furthermore, the temperature fluctuation of a tin bath, the dynamic shift of the peak height and the continuous accumulation of solder oxide in the welding process obviously change the fluidity and the thermodynamic characteristics of molten solder, the defects of solder bridging, soldering omission or internal cavities are induced, in addition, the traditional equipment adopts fixed process parameter setting, the optimal welding conditions of various products are difficult to be considered, finally, the process parameter adjustment completely depends on manual intervention of operators according to the post-welding detection result, the hysteresis regulation mechanism cannot realize real-time optimization and defect prevention in the production process, and the quality fluctuation is difficult to control. In view of the above, there is a need in the art for improvements. Disclosure of Invention An object of an embodiment of the present invention is to provide a capacitive screen circuit welding device, which aims to solve the above problems. The invention is realized in such a way, a welding device for a capacitive screen circuit comprises a welding table, a conveyor used for conveying a PCB is arranged on the welding table, a protective cover is arranged outside the conveyor, a heating system used for preheating the PCB and welding equipment used for welding the PCB are arranged in the protective cover, a scaling powder sprayer is arranged on one side of the protective cover, and the welding device further comprises a regulation and control system, wherein the regulation and control system comprises: The pretreatment state evaluation module is used for constructing a pretreatment state evaluation model based on the actual measurement of the preheating temperature of the PCB surface, the standard reaching rate of an actual measurement temperature curve of a preheating zone, and the deviation between a flux spray quantity set value and a flowmeter feedback value, and outputting a pretreatment state index; The process treatment state evaluation module is used for constructing a process treatment state evaluation model based on the temperature stability of the tin bath, the real-time reading of the peak height sensor and the content of the solder oxide, and outputting a process treatment state index; the PCB welding quality prediction module is used for constructing a PCB welding quality prediction model based on the element layout density, the PCB thickness/aperture ratio, the transmission speed, the pretreatment state index and the process treatment state index and outputting a welding quality prediction index; The turbulence wave self-adaptive regulation and control module is used for constructing a turbulence wave self-adaptive regulation and control model based on a welding quality prediction index, preset turbulence wave intensity and a bridge rate detection after welding of a front block of PCB, outputting target turbulence wave intensity and regulating in the welding process of the next same product; and the laminar flow wave intensity regulation and control module is used for outputting the target laminar flow wave intensity and regulating the welding process of the next same product. In a further technical scheme, in the preprocessing state evaluation model, the preprocessing state index is output by the following modes: Multiplying the normalized preheating temperature index, the measured temperature curve standard reaching rate of the preheating zone and the exponential decay function output value taking the absolute value of the relative devia