Precise injection molding CCD mold intelligent monitoring control system based on machine vision

Abstract

The invention belongs to the technical field of precision injection molding production monitoring, and discloses a precision injection molding CCD mold intelligent monitoring control system based on machine vision. Comprising a mold closing system test module, a mold closing system analysis module, an injection molding process state monitoring module, an injection molding process state analysis module, a product quality state monitoring module and a product quality state analysis module. According to the method, the test result of the mold closing system and the injection molding process state are analyzed, the quality condition of the precise injection mold is reflected from different aspects, the blindness of quality problem checking is reduced through the analysis mode, the possibility of rapidly solving the potential quality hazards of the mold is increased, and the quality condition of the precise injection mold is reflected and guaranteed in an all-around mode. According to the method, feedback analysis is performed on the mold quality based on the injection product quality, so that the precision and timeliness of mold maintenance are improved, the instability of the product quality is reduced, and the continuity of the whole production process is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of precision injection molding production monitoring, and relates to a precision injection molding CCD mold intelligent monitoring and control system based on machine vision. Background Art

[0002] Precision injection molding is an injection molding technology that aims to produce plastic products with high-precision dimensions, excellent surface quality and stable physical properties. It has strict requirements on molds, injection molding equipment, raw materials and process control, and can accurately mold plastic raw materials into complex and precise product shapes. Monitoring precision injection molding can control product dimensional accuracy, surface quality and internal structure in real time, ensure stable product quality, optimize the injection molding process, reduce defective and waste products, improve production efficiency, protect molds and extend their service life, and ensure production safety. Therefore, intelligent monitoring and control of precision injection molding CCD molds based on machine vision is of great significance.

[0003] In the prior art, there are also related solutions for precision injection molding production monitoring technology. For example, a Chinese invention patent application with publication number CN117635595A is for a method for visual inspection of the surface quality of a precision injection mold base, which includes: obtaining a grayscale image, analyzing the grayscale value, gradient value, and area of ​​the pixel points in the connected domain according to the visual inspection method, and obtaining a characteristic factor. Then, the position change, gradient value, and gradient value of the closed edge line of the boundary of the connected domain are analyzed to obtain the glossiness value. Finally, the grayscale value of the edge pixel points in the sub-region, the boundary edge line and area of ​​the sub-region are analyzed to obtain the degree of change value. Through the characteristic factor, glossiness value, and degree of change value, the overall characteristic value is obtained, the defective area is determined, and the quality of the surface of the precision injection mold base is judged.

[0004] In addition, a Chinese invention patent application for a method for visually detecting surface defects of an injection mold with publication number CN118071753A comprises: obtaining a grayscale image of the injection mold. Obtaining a second edge image. Obtaining edge feature indicators of the edge based on the fluctuation of each edge in the second edge image. Obtaining the grayscale change consistency of the edge based on the grayscale change direction of the pixel points in the edge. Obtaining the possibility of the edge as a texture edge based on the difference in edge feature indicators and grayscale change consistency of different edges in the neighborhood area. Obtaining several defective edges of the second edge image. Obtaining several defective areas of the grayscale image of the injection mold based on the distances between different defective edges and the difference in edge feature indicators.

[0005] Although the above two schemes have proposed some solutions for precision injection molding production monitoring, there are still certain limitations: on the one hand, the existing technical solutions only judge abnormal situations based on the surface characteristics of precision injection molds, lacking real-time analysis and control of the actual production process. This analysis method reduces the accuracy of abnormal judgment, because the internal temperature, pressure, material flow and other factors in the mold production process have a significant impact on product quality. Only by observing the surface characteristics, problems such as internal stress concentration of products caused by uneven cooling are difficult to detect, increasing the risk of problematic products flowing into the next process. At the same time, it also reduces the preventive nature of the production process. Due to the inability to analyze dynamic parameters such as plastic injection speed and temperature changes in real time, it is difficult to give early warnings for possible abnormalities, increasing the probability of adverse situations such as production interruptions and resource waste, which is not conducive to ensuring efficient and stable production.

[0006] On the other hand, the existing technical solutions lack feedback analysis of mold quality based on injection molding product quality. This analysis method reduces the timeliness of quality improvement. When quality problems such as flash and shrinkage occur in products, it is difficult to feedback the problems to the mold quality level. The hidden dangers of poor mold precision and abnormal cavity surface roughness are difficult to detect in time, increasing the risk of continuous fluctuations in product quality. At the same time, this lack also reduces the efficiency of production operations. It is impossible to accurately optimize the mold according to the product status, resulting in an increase in repeated mold debugging and frequent rework, which increases the consumption of manpower, material resources and time costs, and hinders enterprises from delivering qualified products on time. Summary of the invention

[0007] In view of this, in order to solve the problems raised in the above background technology, a precision injection molding CCD mold intelligent monitoring and control system based on machine vision is proposed.

[0008] The purpose of the present invention can be achieved through the following technical solutions: a precision injection molding CCD mold intelligent monitoring and control system based on machine vision, including: a mold clamping system test module, which is used to test the clamping system before the injection molding operation, and obtain the clamping data of the mold, including monitoring the gap width and monitoring the position offset distance, and analyzing the tightness evaluation and positioning accuracy of the clamping system.

[0009] The mold clamping system analysis module is used to determine whether the injection molding operation is allowed based on the tightness evaluation and positioning accuracy of the clamping system.

[0010] The injection molding process status monitoring module is used to monitor the injection molding process of precision injection molding, arrange the temperature monitoring points of the mold to obtain several temperature monitoring points, obtain the temperature of each temperature monitoring point in real time, analyze the injection molding temperature control evaluation, and obtain the moving speed of each ejector corresponding to the ejection mold operation, and analyze the ejection mold speed control evaluation.

[0011] The injection molding process status analysis module is used to determine whether there is an abnormality in the injection molding process based on the injection molding temperature control evaluation status and the top mold speed control evaluation status corresponding to the injection molding process. If so, the specific abnormality direction is further identified, and the abnormality direction includes injection molding temperature control abnormality and top mold speed control abnormality.

[0012] The product quality status monitoring module is used to monitor the quality of precision injection molded products, obtain the three-dimensional data of each injection molded product, analyze the dimensional accuracy evaluation of the injection molded products, and use CCD equipment to collect the surface image of each injection molded product to analyze the surface quality evaluation of the injection molded products.

[0013] The product quality status analysis module is used to determine whether the injection molding product production process meets the process requirements based on the dimensional accuracy evaluation and surface quality evaluation of the injection molding product.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention analyzes the test results of the mold clamping system and the injection process status, reflecting the quality of the precision injection mold from different aspects. This analysis method reduces the blindness of quality problem investigation and increases the possibility of quickly resolving mold quality risks. At the same time, it reduces the uncertainty of the production process, and can reasonably set process parameters based on real-time data to avoid product defects and mold losses caused by improper parameters, thereby increasing production stability and efficiency. It also reduces the long-term operating costs of the enterprise and comprehensively reflects and guarantees the quality of precision injection molds.

[0015] (2) The present invention conducts feedback analysis on mold quality based on the quality of injection molded products. This analysis method increases the accuracy and timeliness of mold maintenance. It reduces the instability of product quality. Continuous feedback promotes continuous optimization of mold quality, reduces quality fluctuations between batches of products, increases the output ratio of high-quality products, improves the continuity of the overall production process, avoids frequent production interruptions due to quality problems, and ensures the production efficiency of the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0017] Figure 1 It is a schematic diagram of the connection of each module of the system of the present invention.

[0018] Figure 2 A flowchart for judging whether an injection molding operation is allowed corresponding to an embodiment provided by the present invention.

[0019] Figure 3 A flowchart for determining whether an abnormality exists in an injection molding process corresponding to an embodiment provided by the present invention.

[0020] Figure 4 A flowchart for judging whether the production process of an injection molding product corresponding to an embodiment provided by the present invention meets the process requirements. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] See also Figure 1 As shown, the present invention provides a precision injection molding CCD mold intelligent monitoring and control system based on machine vision, including a mold clamping system testing module, a mold clamping system analysis module, an injection molding process state monitoring module, an injection molding process state analysis module, a product quality state monitoring module and a product quality state analysis module, wherein the mold clamping system testing module is connected to the mold clamping system analysis module, the mold clamping system analysis module is connected to the injection molding process state monitoring module, the injection molding process state monitoring module is connected to the injection molding process state analysis module, the injection molding process state analysis module is connected to the product quality state monitoring module, and the product quality state monitoring module is connected to the product quality state analysis module.

[0023] The mold clamping system test module is used to test the clamping system before the injection molding operation, obtain the clamping data of the mold, including monitoring the gap width and monitoring the position offset distance, and analyze the tightness evaluation and positioning accuracy of the clamping system.

[0024] It should be explained that the reason for testing the clamping system before the injection molding operation is: on the one hand, it effectively guarantees product quality. If the clamping system has problems such as uneven clamping force, the mold cavity cannot be closed during injection molding, and the plastic melt seeps out, which will cause flash and burrs on the product, affecting dimensional accuracy and surface finish. Testing in advance can discover and resolve hidden dangers to ensure the production of qualified products. On the other hand, this is an effective protection for the mold. In view of the high force on the mold during injection molding, if there is a problem with the template parallelism or guide components of the clamping system, forced injection molding will cause excessive force on the local part of the mold, accelerated wear or even damage. Testing can eliminate risks and extend the life of the mold. Furthermore, it can greatly improve production efficiency. If a clamping system failure is discovered in the middle of injection molding, downtime for maintenance and scrapping of semi-finished products will cost a lot of money. Testing and troubleshooting in advance can ensure smooth injection molding and reduce interruptions.

[0025] In a preferred embodiment of the present invention, the tightness evaluation situation requires constructing a tightness evaluation index of the mold clamping system, and the specific method is as follows: extract the monitoring gap width of the mold, and then calculate the difference with the preset reference gap width to obtain the absolute value to obtain the monitoring gap width deviation of the mold clamping system, calculate the ratio of the monitoring gap width deviation of the mold clamping system to the preset reference gap width, and then take the inverse to obtain the tightness evaluation index of the mold clamping system.

[0026] It should be explained that the reason for choosing to monitor the gap width as an influencing factor for the tightness evaluation of the mold clamping system is: First, it can intuitively present the mold clamping effect. The gap width directly quantifies the closed state of the mold. Too wide a width will cause the melt to seep out, causing product flash and overflow, affecting the appearance and precision. Accurate monitoring can grasp the tightness of the mold clamping. Second, it is related to product quality. Uneven gaps cause uneven melt filling, causing product deformation and warping. Monitoring it can eliminate quality risks in advance. Third, it can warn of mold wear. Long-term wear and tear of the mold will change the gap width. Monitoring can detect it in time and facilitate preventive maintenance. Fourth, it helps process optimization. According to the gap width and actual conditions, the mold clamping parameters can be adjusted in a targeted manner to improve production efficiency and competitiveness.

[0027] In a preferred embodiment of the present invention, the positioning accuracy situation requires constructing a positioning accuracy index of the mold clamping system, and the specific method is as follows: extracting the monitoring position offset distance of the mold, and then performing a difference calculation with a preset position offset distance threshold to obtain the monitoring position offset distance anomaly of the mold clamping system, performing a ratio calculation between the monitoring position offset distance anomaly of the mold clamping system and the preset position offset distance threshold, and then taking the inverse to obtain the positioning accuracy index of the mold clamping system.

[0028] It should be explained that the reason for choosing the monitoring position offset distance as an influencing factor of the positioning accuracy of the clamping system is: on the one hand, it can ensure product quality. The offset of the clamping position will cause inaccurate docking between the cavity and the core, uneven wall thickness of the product, and easy breakage. Monitoring can correct errors in advance to ensure reliability. On the other hand, it is beneficial to protect the mold. Inaccurate position causes uneven force on the parts, accelerates wear and deformation, and real-time monitoring can adjust the clamping state and reduce maintenance costs. Furthermore, it stabilizes the production process. The offset will cause problems such as poor melt flow and incomplete filling, which interferes with production continuity. Monitoring helps maintain efficient production. In addition, the process parameters can be optimized. The clamping parameters can be accurately adjusted according to the monitoring results to match different needs and improve the process level.

[0029] The mold clamping system analysis module is used to determine whether the injection molding operation is allowed based on the tightness evaluation and positioning accuracy of the clamping system.

[0030] In a preferred embodiment of the present invention, please refer to Figure 2 As shown, the specific analysis method for determining whether the injection molding operation is allowed is as follows: extract the tightness evaluation index and positioning accuracy index of the clamping system, and then sum them up according to the weights to obtain the clamping system test evaluation index of the clamping system, and then compare it with the pre-set clamping system test evaluation index threshold.

[0031] Exemplarily, the weights corresponding to the compactness evaluation index and the positioning accuracy index are 0.6 and 0.4 respectively.

[0032] It should be explained that the weights corresponding to the tightness evaluation index and the positioning accuracy index are set based on the following: On the one hand, based on the degree of impact on product quality, poor tightness can easily lead to flash and burrs on the product, affecting the appearance and dimensional accuracy; insufficient positioning accuracy can cause uneven wall thickness or even cracks on the product. If high-precision appearance parts are produced, the tightness weight is increased, and the factor with the greatest impact on quality has a higher weight. On the other hand, considering the correlation between mold loss, poor tightness accelerates the wear of the mold sealing parts, and inaccurate positioning can easily cause local deformation and cracking. When the mold cost is high and the durability requirements are high, the weight of factors that have a great impact on mold loss is increased, so as to reasonably distribute the weights and ensure production.

[0033] If the mold clamping system test evaluation index is greater than the mold clamping system test evaluation index threshold, it is determined that the injection molding operation is allowed; otherwise, it is determined that the injection molding operation is not allowed.

[0034] Exemplarily, the mold clamping system test evaluation index threshold is 0.85.

[0035] The injection molding process status monitoring module is used to monitor the injection molding process of precision injection molding, arrange temperature monitoring points on the mold to obtain a number of temperature monitoring points, obtain the temperature of each temperature monitoring point in real time, analyze the injection molding temperature control evaluation situation, and simultaneously obtain the moving speed of each ejector pin corresponding to the ejection mold operation, and analyze the ejection mold speed control evaluation situation.

[0036] It should be explained that the reasons for monitoring the injection molding process of precision injection molding are: First, it is related to product quality. Uneven temperature distribution of the mold will cause changes in the flow characteristics of the plastic melt in the cavity, resulting in defects such as shrinkage marks, bubbles, flow marks, etc., affecting the appearance and internal quality of the product. By setting up temperature monitoring points and real-time monitoring, the temperature control strategy can be adjusted in time to ensure perfect molding of the product. Second, to protect the mold. During injection molding, the mold is subjected to high temperature and high pressure. If the temperature is out of control, local overheating will accelerate mold wear and deformation, shorten the life of the mold, and real-time temperature monitoring can provide early warning to avoid damage to the mold. Third, optimize production efficiency. Accurately grasping the injection molding temperature and ejection mold speed can flexibly adjust the process parameters according to actual conditions, reduce the defective rate, shorten the injection molding cycle, and ensure efficient and smooth production. In addition, obtaining the ejector pin movement speed can prevent improper ejector operation from damaging the product and ensure the quality of product demolding.

[0037] In a preferred embodiment of the present invention, the analysis of the injection molding temperature control evaluation situation requires the construction of an injection molding temperature control evaluation index corresponding to the injection molding process, and the specific method is as follows: extract the temperature of each temperature monitoring point, respectively recorded as T i , where i represents the number of the temperature monitoring point, i=1,2......I, and I represents the number of the temperature monitoring points.

[0038] Using the formula The injection temperature control evaluation index ZTCi corresponding to the injection molding process is obtained by analysis, where T 0 represents the preset reference temperature, ΔT represents the allowable difference between the preset reference temperature and the temperature corresponding to the temperature monitoring point, and max() represents the maximum value.

[0039] In a preferred embodiment of the present invention, the analysis of the ejector speed control evaluation situation requires the construction of an ejector speed control evaluation index corresponding to the injection molding process. The specific method is as follows: extract the moving speed of each ejector pin corresponding to the ejector operation, which is recorded as V j , where j represents the number of the ejector pin, j=1,2......J, and J represents the number of ejector pins.

[0040] Using the formula The top mold speed control evaluation index DMCi corresponding to the injection molding process is obtained by analysis, where V 0represents a preset reference moving speed, and ΔV represents the allowable difference between the preset reference moving speed and the moving speed of the ejector.

[0041] The injection molding process status analysis module is used to determine whether there is an abnormality in the injection molding process based on the injection molding temperature control evaluation status and the top mold speed control evaluation status corresponding to the injection molding process. If so, further identify the specific abnormal direction, and the abnormal direction includes injection molding temperature control abnormality and top mold speed control abnormality.

[0042] In a preferred embodiment of the present invention, please refer to Figure 3 As shown, the specific process of determining whether there is an abnormality in the injection molding process is as follows: extracting the injection molding temperature control evaluation index and the top mold speed control evaluation index corresponding to the injection molding process, and then comparing them with the pre-set temperature control evaluation index threshold and the top mold speed control evaluation index threshold, respectively.

[0043] Exemplarily, the temperature control evaluation index threshold is 0.9, and the top mold speed control evaluation index threshold is 0.95.

[0044] If the injection molding temperature control evaluation index corresponding to the injection molding process is less than the temperature control evaluation index threshold or the top mold speed control evaluation index is less than the top mold speed control evaluation index threshold, it is judged that there is an abnormality in the injection molding process; otherwise, it is judged that there is no abnormality in the injection molding process.

[0045] In a preferred embodiment of the present invention, the specific method of identifying the specific abnormal direction is: if the injection temperature control evaluation index is less than the temperature control evaluation index threshold, the specific abnormal direction is identified as injection temperature control abnormality; if the top mold speed control evaluation index is less than the top mold speed control evaluation index threshold, the specific abnormal direction is identified as top mold speed control abnormality.

[0046] It should be noted that the specific abnormality may be one or both of the abnormality in injection temperature control and the abnormality in ejection mold speed control.

[0047] It should be noted that the present invention analyzes the test results of the mold clamping system and the state of the injection molding process, reflecting the quality of the precision injection mold from different aspects. This analysis method reduces the blindness of quality problem investigation and increases the possibility of quickly solving the hidden dangers of mold quality. At the same time, it reduces the uncertainty of the production process, and can reasonably set the process parameters based on real-time data to avoid product defects and mold losses caused by improper parameters, thereby increasing the stability and efficiency of production. It also reduces the long-term operating costs of the enterprise and comprehensively reflects and guarantees the quality of precision injection molds.

[0048] The product quality status monitoring module is used to monitor the quality of precision injection molded products, obtain three-dimensional data of each injection molded product, analyze the dimensional accuracy evaluation of the injection molded products, and use CCD equipment to collect surface images of each injection molded product to analyze the surface quality evaluation of the injection molded products.

[0049] In a preferred embodiment of the present invention, the analysis of the dimensional accuracy evaluation of the injection molded products requires the construction of a dimensional accuracy evaluation index for the injection molded products, which is specifically performed as follows: extracting the three-dimensional data of each injection molded product, and then obtaining the volume and surface area corresponding to each injection molded product, recorded as ZV k , ZS k , where k represents the number of the injection molded product, k=1,2......K, K represents the number of the injection molded products.

[0050] Using the formula The dimensional accuracy evaluation index DAei of the injection molded product is obtained by analysis, where ZV 0 represents the preset reference volume, ΔZV represents the allowable difference between the preset reference volume and the volume of the injection molded product, and ZS 0 represents a preset reference surface area, and ΔZS represents the allowable difference between the preset reference surface area and the surface area of ​​the injection molded product.

[0051] It should be explained that the reasons for choosing volume and surface area as factors affecting the dimensional accuracy evaluation index of injection molded products are: First, it is related to product function. For example, the volume of an injection molded container determines the amount of liquid it can hold, and the surface area affects the performance of interaction with the outside world. Large deviations can lead to malfunctions. Second, related to mold design and manufacturing, the dimensional accuracy of the product is affected by the mold cavity. The volume and surface area can reflect changes in the cavity. Monitoring them can infer mold problems and help with timely maintenance. Third, based on the convenience of quality control, compared with complex three-dimensional dimensions, volume and surface area are easy to measure and can be quickly obtained using simple tools and methods, which is convenient for random inspections on the production line or in the laboratory to ensure stable product quality.

[0052] In a preferred embodiment of the present invention, the surface quality evaluation of the injection molded product needs to construct a surface quality evaluation index of the injection molded product, and the specific method is as follows: extract the surface image of each injection molded product collected by the CCD device, and then locate the position of each defect corresponding to the surface image of each injection molded product, and obtain the number of surface defects of each injection molded product by counting, which is recorded as QX k , and use image processing software to obtain the surface defect area of ​​each injection molded product, recorded as QS k .

[0053] It should be noted that an embodiment of locating the position of each defect corresponding to the surface image of each injection molded product corresponds to an analysis method: extracting the surface image of each injection molded product collected by a CCD device, and then performing grayscale processing to obtain a grayscale image corresponding to each injection molded product, obtaining the grayscale value of each pixel in the grayscale image corresponding to each injection molded product, performing difference calculation between the grayscale value of each pixel in the grayscale image corresponding to each injection molded product and the pre-set reference grayscale value corresponding to each defect to obtain the grayscale value deviation corresponding to each pixel and each defect, and then performing ratio calculation with the corresponding reference grayscale value of each defect and taking the inverse to obtain the grayscale value similarity corresponding to each pixel and each defect.

[0054] The gray value similarity between each pixel of each injection molded product and each defect is compared with the preset gray value similarity threshold. If the gray value similarity between a pixel and a defect is greater than the gray value similarity threshold, the pixel is judged to be a defective pixel, and then the binary image corresponding to each injection molded product is obtained. The binary image is marked as a region, and each connected defective pixel is marked as a defective region, and the position of each defect corresponding to each injection molded product is obtained.

[0055] Exemplarily, the defects may be flow marks, silver streaks, shrinkage marks, bubbles, scratches, etc.

[0056] It should be explained that the reasons for choosing the number of surface defects and the area of ​​surface defects as the influencing factors of the surface quality evaluation index of injection molding products are: on the one hand, the number of surface defects directly reflects the stability of quality. For precision electronic and medical products, small defects will affect the function, appearance or safety, and their fluctuations are related to process problems. A sudden increase in the number indicates abnormal parameters such as injection and mold temperature, which helps to make timely adjustments to maintain stability. On the other hand, the area of ​​surface defects has different effects on product performance and appearance. Large-area defects seriously damage the quality of optical and interior products. It is also used to measure the severity of defects and the cost of repair. Large-area defects are difficult to repair and costly. Statistical analysis can help companies control quality and reduce losses.

[0057] Using the formula The surface quality evaluation index SQei of the injection molded product is obtained by analysis, where QX 0 Indicates the preset reference defect quantity, QS 0 Indicates the surface area of ​​the injection molded product.

[0058] The product quality status analysis module is used to determine whether the production process of the injection molding product meets the process requirements based on the dimensional accuracy evaluation and surface quality evaluation of the injection molding product.

[0059] In a preferred embodiment of the present invention, please refer to Figure 4As shown, the specific method for judging whether the injection molding product production process meets the process requirements is as follows: extract the dimensional accuracy evaluation index and surface quality evaluation index of the injection molding product, and then sum them up according to the weights to obtain the injection molding product production process evaluation index, and then compare it with the pre-set injection molding product production process evaluation index threshold.

[0060] Exemplarily, the dimensional accuracy evaluation index and the surface quality evaluation index have corresponding weights of 0.55 and 0.45, respectively.

[0061] It should be noted that the dimensional accuracy evaluation index and the surface quality evaluation index correspond to the weight setting basis: in terms of dimensional accuracy, the weight is set according to the functional impact and assembly adaptation. For example, for precision gears, dimensional deviation will destroy the operation of the machinery, and the electronic product housing cannot be tightly assembled if it does not fit the size, so the dimensional accuracy of key products has a high weight. In terms of surface quality, for appearance-dominated products such as high-end electronic housings, minor flaws will damage competitiveness, so the weight should be large; for medical and food packaging injection moldings, surface defects are easy to hide dirt and grime, which poses a safety hazard, and the weight should not be low either. The two are summed up by weight to obtain the production process evaluation index, which is then compared with the threshold to strictly control the injection molding quality.

[0062] If the injection molding product production process evaluation index is less than the injection molding product production process evaluation index threshold, it is judged that the injection molding product production process does not meet the process requirements; otherwise, it is judged that the injection molding product production process meets the process requirements.

[0063] It should be noted that the present invention performs feedback analysis on mold quality based on the quality of injection molded products, and this analysis method increases the accuracy and timeliness of mold maintenance. It reduces the instability of product quality, and continuous feedback promotes continuous optimization of mold quality, reduces quality fluctuations between batches of products, increases the output ratio of high-quality products, improves the continuity of the overall production process, avoids frequent interruptions of production due to quality problems, and ensures the production efficiency of the enterprise.

[0064] The above contents are merely examples and explanations of the concept of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the present invention, they shall all fall within the protection scope of the present invention.

Claims

1. A precision injection molding CCD mold intelligent monitoring and control system based on machine vision, characterized in that: include: The mold clamping system test module is used to test the clamping system before the injection molding operation, obtain the mold clamping data, including monitoring the gap width and monitoring the position offset distance, and analyze the tightness evaluation and positioning accuracy of the clamping system; The mold clamping system analysis module is used to determine whether the injection molding operation is allowed based on the tightness evaluation and positioning accuracy of the clamping system; The injection molding process status monitoring module is used to monitor the injection molding process of precision injection molding, arrange the temperature monitoring points of the mold to obtain several temperature monitoring points, obtain the temperature of each temperature monitoring point in real time, analyze the injection molding temperature control evaluation, and obtain the moving speed of each ejector corresponding to the ejection mold operation, and analyze the ejection mold speed control evaluation; The injection molding process status analysis module is used to determine whether there is an abnormality in the injection molding process based on the injection molding temperature control evaluation and the top mold speed control evaluation corresponding to the injection molding process, and if so, further identify the specific abnormal direction, which includes injection molding temperature control abnormality and top mold speed control abnormality; The product quality status monitoring module is used to monitor the quality of precision injection molded products, obtain the three-dimensional data of each injection molded product, analyze the dimensional accuracy evaluation of the injection molded products, and use CCD equipment to collect the surface image of each injection molded product to analyze the surface quality evaluation of the injection molded products; The product quality status analysis module is used to determine whether the injection molding product production process meets the process requirements based on the dimensional accuracy evaluation and surface quality evaluation of the injection molding product.

2. The machine vision-based precision injection molding CCD mold intelligent monitoring and control system according to claim 1, characterized in that: The tightness evaluation situation requires the construction of a tightness evaluation index of the clamping system, and the specific method is as follows: The monitoring gap width of the mold is extracted, and then the difference between it and the preset reference gap width is calculated and the absolute value is taken to obtain the monitoring gap width deviation of the clamping system. The monitoring gap width deviation of the clamping system is calculated by ratio with the preset reference gap width and the inverse is taken to obtain the tightness evaluation index of the clamping system.

3. The machine vision-based precision injection molding CCD mold intelligent monitoring and control system according to claim 2, characterized in that: The positioning accuracy situation requires the construction of the positioning accuracy index of the clamping system, and the specific method is as follows: The monitoring position offset distance of the mold is extracted, and then the difference is calculated with the preset position offset distance threshold to obtain the monitoring position offset distance anomaly of the mold clamping system. The monitoring position offset distance anomaly of the mold clamping system is calculated by ratio with the preset position offset distance threshold, and the inverse is taken to obtain the positioning accuracy index of the mold clamping system.

4. The machine vision-based precision injection molding CCD mold intelligent monitoring and control system according to claim 3, characterized in that: The specific analysis method for determining whether the injection molding operation is allowed is as follows; Extract the tightness evaluation index and positioning accuracy index of the mold clamping system, then sum and calculate the mold clamping system test evaluation index of the mold clamping system according to the weight, and then compare it with the preset mold clamping system test evaluation index threshold; If the mold clamping system test evaluation index is greater than the mold clamping system test evaluation index threshold, it is determined that the injection molding operation is allowed; otherwise, it is determined that the injection molding operation is not allowed.

5. The machine vision-based precision injection molding CCD mold intelligent monitoring and control system according to claim 1, characterized in that: The analysis of the injection molding temperature control evaluation situation requires the construction of an injection molding temperature control evaluation index corresponding to the injection molding process, and the specific method is as follows: Extract the temperature of each temperature monitoring point and record it as T i , where i represents the number of the temperature monitoring point, i=1,2......I, I represents the number of the temperature monitoring points; Using the formula The injection temperature control evaluation index ZTCi corresponding to the injection molding process is obtained by analysis, where T0 represents the preset reference temperature, ΔT represents the allowable difference between the preset reference temperature and the temperature corresponding to the temperature monitoring point, and max() represents the maximum value.

6. The machine vision-based precision injection molding CCD mold intelligent monitoring and control system according to claim 5, characterized in that: The analysis of the top mold speed control evaluation situation requires the construction of a top mold speed control evaluation index corresponding to the injection molding process, and the specific method is as follows: Extract the moving speed of each ejector pin corresponding to the ejection operation, which is recorded as V j , where j represents the number of the ejector pin, j=1,2...J, J represents the number of ejector pins; Using the formula The ejector speed control evaluation index DMCi corresponding to the injection molding process is obtained by analysis, wherein V0 represents a preset reference moving speed, and ΔV represents the allowable difference between the preset reference moving speed and the moving speed of the ejector.

7. The machine vision-based precision injection molding CCD mold intelligent monitoring and control system according to claim 6, characterized in that: The specific process of judging whether there is an abnormality in the injection molding process is as follows: Extracting the injection temperature control evaluation index and the top mold speed control evaluation index corresponding to the injection molding process, and then comparing them with the preset temperature control evaluation index threshold and the top mold speed control evaluation index threshold respectively; If the injection molding temperature control evaluation index corresponding to the injection molding process is less than the temperature control evaluation index threshold or the top mold speed control evaluation index is less than the top mold speed control evaluation index threshold, it is judged that the injection molding process is abnormal, otherwise, it is judged that the injection molding process is not abnormal; The specific method of identifying the specific abnormal direction is: If the injection temperature control evaluation index is less than the temperature control evaluation index threshold, the specific abnormality is identified as injection temperature control abnormality; if the top mold speed control evaluation index is less than the top mold speed control evaluation index threshold, the specific abnormality is identified as top mold speed control abnormality.

8. The machine vision-based precision injection molding CCD mold intelligent monitoring and control system according to claim 1, characterized in that: The analysis of the dimensional accuracy evaluation of the injection molded product requires the construction of a dimensional accuracy evaluation index for the injection molded product, and the specific method is as follows: Extract the 3D data of each injection molded product, and then obtain the volume and surface area of ​​each injection molded product, denoted as ZV k , ZS k , where k represents the number of the injection molded product, k=1,2...K, K represents the number of injection molded products; Using the formula The analysis results in the dimensional accuracy evaluation index DAei of the injection molded product, where ZV0 represents a preset reference volume, ΔZV represents the allowable difference between the preset reference volume and the volume of the injection molded product, ZS0 represents a preset reference surface area, and ΔZS represents the allowable difference between the preset reference surface area and the surface area of ​​the injection molded product.

9. A machine vision-based precision injection molding CCD mold intelligent monitoring and control system as claimed in claim 8, characterized in that: The analysis of the surface quality evaluation of the injection molded product requires the construction of a surface quality evaluation index for the injection molded product, and the specific method is as follows: Extract the surface image of each injection molded product collected by CCD equipment, and then locate the position of each defect corresponding to the surface image of each injection molded product, and obtain the number of surface defects of each injection molded product, which is recorded as QX k , and use image processing software to obtain the surface defect area of ​​each injection molded product, recorded as QS k ; Using the formula The surface quality evaluation index SQei of the injection molded product is obtained by analysis, where QX0 represents the preset reference defect number and QS0 represents the surface area of ​​the injection molded product.

10. The machine vision-based precision injection molding CCD mold intelligent monitoring and control system according to claim 9, characterized in that: The specific method for judging whether the production process of injection molding products meets the process requirements is as follows: Extract the dimensional accuracy evaluation index and surface quality evaluation index of the injection molding product, then sum and calculate the evaluation index of the injection molding product production process according to the weight, and then compare it with the pre-set injection molding product production process evaluation index threshold; If the injection molding product production process evaluation index is less than the injection molding product production process evaluation index threshold, it is judged that the injection molding product production process does not meet the process requirements; otherwise, it is judged that the injection molding product production process meets the process requirements.

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