A method and system for controlling injection molding of a plastic box body of a junction box

Abstract

The application relates to the technical field of injection molding control, and discloses an injection molding control method and system for a plastic box body of a junction box, wherein the method comprises the following steps: acquiring area detection data of the plastic box body of the junction box, extracting a reference from the area detection data to obtain a molding reference state; aligning periodic data according to the molding reference state to obtain a pressure sequence and a temperature sequence; performing arrival time difference analysis based on the pressure sequence to obtain a flow skewness; performing pressure freezing analysis on the pressure sequence and the temperature sequence to obtain a pressure maintaining state and a freezing time sequence; and performing zero mean value cooling perturbation identification according to the temperature sequence. The technical scheme of the combined analysis of the area pressure and temperature and the decoupling technology of the deviation causes can achieve the technical effect of distinguishing the insufficient pressure deviation and the freezing imbalance deviation, can realize accurate identification of the size deviation causes, and can solve the problem that similar pressure results and weight results are not easy to determine the control object.

Description

Technical Field

[0001] This invention relates to the field of injection molding control technology, specifically to an injection molding control method and system for junction box plastic housings, electronic equipment, and storage medium. Background Technology

[0002] In the context of injection molding control for junction box plastic housings, the housing typically features annular sealing edges, terminal mounting posts, wiring holes, and localized thin-walled ribs. The filling paths, pressure holding conditions, and cooling / freezing processes differ across these areas. During molding, shrinkage offset in the terminal mounting area and directional warping in the sealing area may manifest as similar pressure peaks and product weights, making it difficult to accurately distinguish the causes of dimensional deviations using conventional process data.

[0003] Currently, existing technologies typically collect data such as single-point pressure, pressure peak, pressure curve area, product weight, or average mold temperature to determine injection molding quality. After detecting dimensional deviations, the injection molding process parameters are uniformly corrected by increasing the overall holding pressure, extending the holding time, reducing the mold temperature, or extending the cooling time.

[0004] However, existing technologies have significant limitations in practical applications. On the one hand, similar pressure and weight results cannot distinguish between terminal mounting post shrinkage and offset caused by insufficient pressure holding at the far end, or directional warping after demolding caused by regional cooling differences, making it difficult to accurately determine the control object. On the other hand, without accurate identification of the cause, global process correction is prone to creating control conflicts between the box opening sealing edge and the terminal mounting area, making it difficult to simultaneously stabilize the box opening coplanarity and the terminal mounting position accuracy. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an injection molding control method and system for junction box plastic housings, an electronic device, and a storage medium, to at least partially solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides an injection molding control method for a junction box plastic housing, comprising:

[0008] Obtain the area detection data of the junction box plastic body, and perform benchmark extraction on the area detection data to obtain the molding benchmark state;

[0009] Based on the molding reference state, periodic data alignment is performed to obtain pressure and temperature sequences;

[0010] Based on the pressure sequence, time-of-arrival analysis was performed to obtain the flow skewness;

[0011] The pressure and temperature sequences were subjected to pressure holding and freezing analysis to obtain the pressure holding state and freezing time sequence.

[0012] Zero-mean cooling perturbation identification is performed based on the temperature sequence to obtain the thermal response state;

[0013] Based on the aforementioned flow bias state, pressure maintenance state, freezing sequence, and thermal response state, the cause of deviation is decoupled to obtain the insufficient pressure maintenance deviation or freezing imbalance deviation.

[0014] The control amount is allocated to the insufficient charge / protection deviation or the freezing imbalance deviation to obtain the charge / protection correction amount or the limited cooling correction amount;

[0015] Feedback correction is performed based on the filling and maintenance correction amount or the limited cooling correction amount to obtain the injection molding control result of the box body.

[0016] Preferably, periodic data alignment is performed based on the molding reference state to obtain a pressure sequence and a temperature sequence, including:

[0017] The reference time points of the forming reference state are extracted to obtain the pressure reference time point and the temperature reference time point;

[0018] Using the pressure and temperature reference times as constraints, the pressure and temperature data in the regional detection data are time-shifted and the sampling interval is unified to obtain aligned pressure and temperature data.

[0019] The aligned pressure and temperature data are then processed by region correspondence to obtain pressure and temperature sequences.

[0020] Preferably, based on the pressure sequence, time-of-arrival analysis is performed to obtain the flow skewness, including:

[0021] The pressure sequence is analyzed to identify the pressure rise segment, and the pressure rise starting point of each region is obtained.

[0022] The time difference between each region is calculated based on the pressure rise point in each region.

[0023] By comparing the time differences of arrival between the aforementioned regions in a directional manner, the pressure sequence relationship is obtained;

[0024] Based on the arrival time difference and pressure sequence relationship between the regions, skewness determination is performed to obtain the flow skewness.

[0025] Preferably, pressure holding and freezing analysis is performed on the pressure sequence and temperature sequence to obtain the pressure holding state and freezing time sequence, including:

[0026] The pressure sequence is truncated to a holding pressure segment to obtain the holding pressure change data for each region;

[0027] Based on the pressure change data of each region, the pressure decay is compared to obtain the pressure maintenance state of each region.

[0028] The temperature sequence is analyzed to identify the temperature decrease process, and temperature change data for each region is obtained.

[0029] The freezing sequence is obtained by comparing the freezing order based on the temperature change data of each region.

[0030] Preferably, the thermal response state is obtained by identifying zero-mean cooling perturbations based on the temperature sequence, including:

[0031] The temperature sequence is truncated during the cooling stage to obtain a cooling temperature sequence;

[0032] A zero-mean cooling perturbation is applied to the cooling temperature sequence to obtain the temperature change before and after the perturbation.

[0033] The temperature response difference is obtained by extracting the difference between the temperature change before and after the perturbation.

[0034] The strength of heat transfer is determined based on the temperature response difference to obtain the thermal response state.

[0035] Preferably, the deviation causes are decoupled based on the flow bias, pressure maintenance state, freezing sequence, and thermal response state to obtain the inadequate charge / maintenance deviation or freezing imbalance deviation, including:

[0036] The correlation between the flow deviation state and the pressure holding state is determined to identify the region where the pressure arrival is delayed and the pressure holding is insufficient.

[0037] Based on the region where the pressure arrives late and the pressure holding is insufficient, the deviation is attributed to the insufficient pressure holding deviation.

[0038] The freezing sequence and thermal response state are correlated and judged to identify regions where the freezing order is inconsistent and the thermal response is uneven.

[0039] The deviation is attributed to the regions where the freezing order is inconsistent and the thermal response is uneven, resulting in freezing imbalance deviation.

[0040] Preferably, the control amount allocation for the insufficient charge / protection deviation or freezing imbalance deviation is performed to obtain the charge / protection correction amount or the limited cooling correction amount, including:

[0041] The degree of inadequate charging deviation is extracted to obtain the charging deviation amount;

[0042] Based on the filling and holding deviation, the injection speed and holding pressure are allocated to obtain the filling and holding correction amount;

[0043] The degree of the freezing imbalance deviation is extracted to obtain the freezing deviation amount;

[0044] Based on the freezing deviation, the cooling intensity is allocated to each zone to obtain the limited cooling correction amount.

[0045] Preferably, feedback correction is performed based on the filling and maintenance correction amount or the limited cooling correction amount to obtain the injection molding control result of the box body, including:

[0046] The control parameters for the current cycle are generated based on the aforementioned maintenance correction amount or limited cooling correction amount.

[0047] The injection molding process is executed based on the control parameters of the current cycle to obtain the area detection data after the execution.

[0048] The deviation of the region detection data after execution is checked to obtain the check result;

[0049] Based on the verification results, the control parameters for the current cycle are updated to obtain the injection molding control results for the box body.

[0050] Preferably, skewness determination is performed based on the arrival time difference and pressure sequence relationship between the regions to obtain the flow skewness, including:

[0051] The time difference of arrival between the regions and the forming reference state are compared to obtain the time difference deviation result;

[0052] Based on the pressure sequence, the time difference deviation results are marked in direction to obtain the pressure arrival advance region and the pressure arrival lag region;

[0053] By performing region correspondence determination on the pressure arrival advance region and the pressure arrival lag region, the flow offset direction is obtained;

[0054] Based on the flow offset direction and time difference deviation results, the skewness is confirmed to obtain the flow skewness.

[0055] In a second aspect, the present invention provides an injection molding control system for a junction box plastic housing, comprising:

[0056] The reference extraction module is used to acquire the area detection data of the junction box plastic body, and to perform reference extraction on the area detection data to obtain the molding reference state;

[0057] The period alignment module is used to align periodic data according to the forming reference state to obtain pressure sequence and temperature sequence;

[0058] The arrival analysis module is used to perform arrival time difference analysis based on the pressure sequence to obtain the flow skewness.

[0059] The pressure holding and freezing module is used to perform pressure holding and freezing analysis on the pressure sequence and temperature sequence to obtain the pressure holding state and freezing time sequence.

[0060] The perturbation identification module is used to identify zero-mean cooling perturbations based on the temperature sequence to obtain the thermal response state;

[0061] The cause decoupling module is used to decouple the causes of deviations based on the flow bias, pressure maintenance state, freezing sequence and thermal response state to obtain the insufficient charge-maintenance deviation or freezing imbalance deviation.

[0062] The control allocation module is used to allocate control amounts to the insufficient charge / protection deviation or the freezing imbalance deviation to obtain the charge / protection correction amount or the limited cooling correction amount.

[0063] The feedback correction module is used to perform feedback correction based on the filling and maintenance correction amount or the limited cooling correction amount to obtain the injection molding control result of the box body.

[0064] Thirdly, the present invention provides an electronic device including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method in the first aspect.

[0065] Fourthly, the present invention provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method in the first aspect.

[0066] The present invention has the following beneficial effects:

[0067] 1. This invention adopts a regional pressure and temperature joint analysis and deviation cause decoupling technology to achieve the technical effect of distinguishing between insufficient filling and freezing imbalance deviation, realize accurate identification of the cause of dimensional deviation, and solve the problem that it is not easy to determine the control object when the pressure and weight results are similar.

[0068] 2. This invention adopts a technical solution of allocating filling and maintenance correction amounts and limited cooling correction amounts according to the type of deviation, so as to achieve the technical effect of differentiated control of injection pressure and zoned cooling, realize the coordinated stability of the box opening sealing edge and terminal installation area, and solve the problem that global process correction is prone to control conflicts. Attached Figure Description

[0069] Figure 1 This is a schematic flowchart of the injection molding control method provided in an embodiment of the present invention;

[0070] Figure 2 This is a framework diagram of the injection molding control system provided in an embodiment of the present invention. Detailed Implementation

[0071] To enable those skilled in the art to understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort should fall within the scope of protection of the present invention.

[0072] The present invention will now be described in detail with reference to the accompanying drawings:

[0073] This invention discloses a method for controlling the injection molding of a junction box plastic housing, such as... Figure 1 This method is applicable to the injection molding process control of junction box plastic bodies with sealing areas at the box opening, terminal mounting areas, wiring hole areas, mounting post areas, reinforcing rib areas, and locally thin-walled partition rib areas. It is suitable for control scenarios where terminal mounting post position offset, wiring hole shrinkage deviation, decreased coplanarity of the box opening sealing edge, directional warping after demolding, and coupling of dimensional deviations in different areas occur during injection molding.

[0074] The injection molding control method for the plastic housing of the junction box includes the following steps:

[0075] 1. Obtain the area detection data of the plastic box body of the junction box, and extract the benchmark from the area detection data to obtain the molding benchmark state.

[0076] In this step, the key molding areas of the junction box's plastic housing are first identified. These key molding areas include at least the box opening sealing area and the terminal mounting area. The box opening sealing area refers to the annular area at the box opening used for mating with the cover, sealing ring, or assembly structure. The terminal mounting area refers to the area inside the box containing mounting posts, mounting holes, and adjacent connection structures used for supporting, positioning, or fixing terminals.

[0077] In one implementation, when dividing the junction box plastic housing into regions, the sealing area and terminal mounting area are first determined based on the product's three-dimensional structure, mold cavity layout, gate location, and product dimensional tolerance requirements. Then, pressure and temperature detection points are arranged in the sealing area and the terminal mounting area, ensuring that each critical area has at least pressure and temperature data. The region detection data can be acquired by a mold cavity pressure sensor, mold temperature sensor, infrared temperature measurement unit, thermocouple, pressure acquisition module, and injection molding machine control system.

[0078] The regional detection data is recorded as follows: ,

[0079] in, Indicates regional detection data, Indicates the region At sampling time Pressure value, Indicates the region At sampling time Temperature value, Indicates the area code. Indicates the sampling time. Indicates the injection molding cycle number. (Region) It includes at least the box opening sealing area and the terminal mounting area.

[0080] Regional inspection data are collected from the current injection molding production process and historical qualified injection molding processes. For data used for benchmark extraction, inspection data corresponding to boxes that meet the following criteria should be selected: appearance qualified, box opening sealing edge coplanarity qualified, terminal installation position accuracy qualified, wiring hole size qualified, and warping qualified after demolding.

[0081] When extracting benchmarks from regional detection data, the following method can be used:

[0082] First, the regional detection data is screened for validity. If there is a sampling interruption, sensor drift anomaly, pressure jump anomaly, or missing temperature sampling within a certain period, the period is marked as invalid and will not be included in the benchmark extraction. The pressure and temperature data of the valid periods are then denoised using methods such as moving average, low-pass filtering, or outlier removal based on the median.

[0083] The pressure and temperature curves for a qualified cycle are normalized to ensure that data from different cycles have the same start time, end time, and sampling interval. The start time of the cycle can be determined by the injection start signal, screw advance signal, mold closure completion signal, or the moment when the pressure first exceeds the background pressure. The end time of the cycle can be determined by the mold opening signal, ejection signal, or the moment when the temperature approaches a stable demolding state.

[0084] Statistical extraction is performed on the normalized qualified cycle data to obtain the pressure reference curve, temperature reference curve, pressure reference time point, and temperature reference time point. In one embodiment, the pressure reference curve and temperature reference curve are respectively represented as:

[0085] ,

[0086] ,

[0087] in, Indicates the region At sampling time Pressure reference value, Indicates the region At sampling time Temperature reference value, Indicates the qualified period Central region At sampling time Pressure value, Indicates the qualified period Central region At sampling time Temperature value, This indicates the number of qualified cycles participating in the benchmark extraction.

[0088] The pressure reference time point may include the pressure reaching reference time point, the pressure holding start reference time point, the pressure holding end reference time point, and the pressure decay reference time point. The temperature reference time point may include the cooling start reference time point, the temperature drop inflection point reference time point, the freezing judgment reference time point, and the temperature reference time point before demolding.

[0089] In one implementation, the pressure reaches a reference time point. Determined by the rising segment of the pressure reference curve: ,

[0090] in, Indicates the region When the pressure reaches the reference point, Indicates the region The pressure reference value at the beginning of the cycle Indicates the region The pressure reaches the judgment threshold. This threshold can be determined by the qualified cycle pressure noise level, sensor resolution, and cavity pressure rise characteristics.

[0091] Temperature reference time point This can be determined by observing the descent process of the temperature reference curve:

[0092] ,

[0093] in, Indicates the region Temperature reference time point, Indicates the region The freezing point is determined by the material's curing characteristics, the demolding temperature window, and the thickness of the regional structure.

[0094] Therefore, the resulting molding reference state is denoted as:

[0095] ,

[0096] in, Indicates the molding reference state. Indicates the reference time point for the start of pressure holding. Indicates the reference point for the end of pressure holding. Indicates the region and region The pressure between them reaches the reference time difference. Indicates the region and region The frozen reference time difference between them.

[0097] The forming reference state is generated from the qualified cycle data in the regional detection data; it is obtained through validity screening, noise suppression, cycle normalization, statistical extraction and key time point identification; it includes pressure reference curve, temperature reference curve, pressure reference time point, temperature reference time point, holding pressure reference time point and inter-regional reference time difference; its function is to provide a common reference for cycle data alignment, arrival time difference analysis, holding pressure freeze analysis, zero mean cooling perturbation identification and deviation cause decoupling.

[0098] The periodic data is aligned according to the forming reference state to obtain the pressure sequence and temperature sequence.

[0099] This step is used to align the pressure data, temperature data, and molding baseline state collected in the current injection molding cycle with time, sampling, and region correspondence, so that the data of the current cycle can be compared with the baseline state for analysis.

[0100] Specifically, aligning periodic data based on the molding reference state includes the following process:

[0101] The reference time points for the forming reference state are extracted to obtain the pressure reference time point and the temperature reference time point.

[0102] In this step, pressure reference points related to pressure sequence alignment and temperature reference points related to temperature sequence alignment are extracted from the molding reference state. Pressure reference points include the pressure arrival reference point, the pressure holding start reference point, and the pressure holding end reference point. Temperature reference points include the cooling start reference point, the freezing judgment reference point, and the temperature reference point before demolding.

[0103] The pressure reference time point reflects the critical moment when the melt enters the corresponding region or when the holding pressure is transferred to the corresponding region. The temperature reference time point reflects the critical moment when the region enters the stable cooling stage or the frozen state. Extracting the pressure and temperature reference time points can avoid comparison errors caused by slight deviations in injection start time, sampling trigger delays, or controller recording delays in different cycles.

[0104] Using pressure and temperature reference time points as constraints, the pressure and temperature data in the regional detection data are time-shifted and the sampling interval is unified to obtain aligned pressure and temperature data.

[0105] In this step, we first obtain the raw pressure and raw temperature data for the current injection molding cycle. Let the current cycle number be... Current cycle region The raw pressure data is represented as Current cycle region The raw temperature data is represented as ,in, Indicates the original sampling time.

[0106] The current pressure arrival time is identified by analyzing the raw pressure data for the current period. The current temperature reference time point is identified by analyzing the raw temperature data for the current period. Based on the pressure reference time point in the molding reference state. and temperature reference time point Calculate the pressure time shift and temperature time shift:

[0107] ,

[0108] ,

[0109] in, Indicates the region Time shift of pressure data Indicates the region The time shift of temperature data.

[0110] Then, time shift is performed on the current cycle's pressure and temperature data:

[0111] ,

[0112] ,

[0113] in, Indicates the region The pressure data after translation Indicates the region Temperature data after translation.

[0114] After time shifting, the sampling intervals for pressure and temperature data are standardized. If the original sampling interval differs from the baseline sampling interval, interpolation is used to map the data to a unified set of sampling times. Interpolation is performed using linear interpolation, piecewise cubic interpolation, or conformal interpolation. To avoid distortion in the pressure rise and temperature fall segments due to interpolation, interpolation methods that preserve the monotonic characteristics of the curve are preferred.

[0115] The aligned pressure and temperature data are represented as follows:

[0116] ,

[0117] ,

[0118] in, Indicates the region At the unified sampling time Aligned pressure data, Indicates the region At the unified sampling time Aligned temperature data, This indicates pressure alignment processing. This indicates temperature alignment processing.

[0119] The aligned pressure and temperature data are then processed to obtain the pressure and temperature sequences.

[0120] In this step, the aligned pressure data is organized into a pressure sequence according to region number and time order, and the aligned temperature data is organized into a temperature sequence according to region number and time order. If the box-mouth sealing area and the terminal mounting area each include several detection points, the detection points in the same area are first merged to form a region sequence. Region merging uses the average value, weighted average value, maximum deviation value, or representative point selection method. For the box-mouth sealing area, if coplanarity is a concern, the weight of detection points far from the gate area on the annular sealing edge can be increased; for the terminal mounting area, if the positional accuracy of the mounting post is a concern, the weight of detection points near the root of the terminal mounting post or the wiring hole can be increased.

[0121] The pressure sequence can be represented as: ,

[0122] The temperature sequence can be represented as: ,

[0123] in, Represents a pressure sequence. Represents a temperature sequence. Indicates the number of regions. This indicates the number of uniform sampling times.

[0124] The pressure and temperature sequences are generated from the forming reference state and regional detection data; they are obtained through reference time point extraction, time shifting, sampling interval unification, and regional correspondence processing; they include pressure and temperature change data of each region under a unified time reference; their function is to provide a basis for arrival time difference analysis, pressure holding and freezing analysis, and zero-mean cooling perturbation identification.

[0125] Flow skewness is obtained by performing time-of-arrival analysis based on pressure sequences.

[0126] This step is used to identify the difference in the arrival time of the melt between the box opening sealing area and the terminal mounting area based on the pressure sequence, and to determine whether there is a deviation in the melt propagation.

[0127] The pressure rise segment is identified in the pressure sequence to obtain the starting point of pressure rise in each region.

[0128] In this step, the rising segment of the pressure curve in each region of the pressure sequence is identified. The pressure rising segment refers to the stage where the pressure rises rapidly from the background pressure, indicating that the melt has arrived or the pressure has begun to be effectively transmitted. To avoid the influence of noise, the identification of the pressure rising segment is based on a combination of pressure increment, pressure slope, and the stability of continuous sampling points.

[0129] For the region The starting point of rising pressure It can be determined by the following formula:

[0130] ,

[0131] in, Indicates the region The starting point for the rise in pressure, Indicates the region At any moment The pressure value after alignment Indicates the region Pressure increment threshold, Indicates the region At any moment The slope of the pressure change, Indicates the region The slope threshold.

[0132] The slope of the pressure change is expressed as: ,

[0133] If the pressure curve exhibits local fluctuations in a certain area, the pressure increment and pressure slope can be required to meet an upward condition within a series of consecutive sampling points. This method can prevent pressure noise or sensor jitter from being misinterpreted as the arrival of melt.

[0134] The time difference between regions is calculated based on the pressure rise point in each region.

[0135] In this step, the time difference between the pressure rise points of any two regions is calculated. For the sealing area of ​​the box opening and the terminal mounting area, the arrival time difference can be expressed as:

[0136] ,

[0137] in, Indicates the region Relative to region The time difference of arrival, Indicates the region The starting point for the rise in pressure, Indicates the region The starting point for the rise in pressure.

[0138] like A value greater than zero indicates that the region Pressure arrives later than in the region .like Less than zero indicates the region Pressure arrived earlier than in the region When comparing the terminal mounting area and the box opening sealing area, if the arrival time of the terminal mounting area is significantly delayed, it indicates insufficient melt propagation at the far end or high flow path resistance.

[0139] By comparing the arrival time differences between different regions, the order of pressure can be determined.

[0140] In this step, the pressure sequence is determined based on the time difference of arrival between each region. The pressure sequence includes regions where pressure arrives ahead of time, regions where pressure arrives late, and regions where pressure arrives approximately synchronously. If the absolute value of the time difference of arrival between regions is lower than the baseline allowable range, it is judged as approximately synchronous; if the time difference of arrival between regions deviates significantly from the baseline state, the regions where pressure arrives ahead of time and the regions where pressure arrives late are determined.

[0141] The order of stress is expressed as follows:

[0142] ,

[0143] in, Indicates the region and region The order of pressure between them. Indicates the region and region The base time difference between them This indicates the permissible deviation limit for the time difference of arrival.

[0144] Based on the arrival time difference and pressure sequence relationship between different regions, skewness determination is performed to obtain the flow skewness.

[0145] In this step, the arrival time difference between each region is compared with the forming reference state to obtain the time difference deviation result. The time difference deviation result is used to represent the difference in melt arrival time in the current cycle relative to the qualified reference. The time difference deviation result can be expressed as: ,

[0146] in, Indicates the region and region The time difference deviation results.

[0147] Based on the pressure sequence, the time difference deviation is directionally marked to obtain the pressure arrival advance region and the pressure arrival lag region. For example, when the arrival time difference between the terminal mounting area and the box opening sealing area is positive and exceeds the allowable deviation limit, the terminal mounting area is marked as the pressure arrival lag region, and the box opening sealing area is marked as the pressure arrival advance region.

[0148] The flow offset direction is determined by classifying the regions where pressure arrives early and late. This classification involves determining whether the early and late regions fall within the gate sealing area, terminal mounting area, or other critical areas, and then using the gate location and flow path to determine the melt propagation offset direction. If the pressure arrives early in the gate sealing area near the gate, while the pressure lags behind in the terminal mounting area at the far end, the flow offset direction can be determined as shifting towards the gate side. If the pressure arrives early in the terminal mounting area but lags behind in the gate sealing area, it indicates the existence of different local flow offsets.

[0149] The flow skewness is determined by confirming the flow offset direction and time difference deviation results. The flow skewness includes no obvious skewness, near gate skewness, far-end lag skewness, box-mouth priority skewness, and terminal area lag skewness.

[0150] The flow skewness is generated by the pressure sequence; it is obtained by identifying the pressure rise segment, calculating the arrival time difference, comparing the pressure sequence relationship, and confirming the skewness; it includes the pressure arrival advance region, the pressure arrival lag region, the flow offset direction, and the time difference deviation results; its function is to provide melt propagation side evidence for decoupling the cause of the deviation.

[0151] Pressure holding and freezing analysis was performed on the pressure and temperature sequences to obtain the pressure holding state and freezing time sequence.

[0152] This step is used to simultaneously analyze the pressure maintenance during the pressure holding phase and the order in which different regions enter the freezing state during the temperature drop process.

[0153] The pressure sequence is truncated to obtain the pressure holding period data for each region.

[0154] In this step, pressure data for the holding pressure segment of each region is extracted from the pressure sequence based on the holding pressure start and end reference points in the molding reference state. If the holding pressure switching time in the current cycle is provided by the injection molding machine controller, the holding pressure segment can be determined by combining the controller signal and the molding reference state. The purpose of extracting the holding pressure segment is to exclude the rapid filling rise stage and the pressure release stage in the later cooling stage, so that the holding pressure maintenance state only reflects the holding pressure transmission and pressure compensation capabilities.

[0155] For the region The change in holding pressure can be expressed as:

[0156] ,

[0157] in, Indicates the region Data on changes in holding pressure, This indicates the start point of the current cycle's pressure holding period. This indicates the end point of the current cycle's pressure holding period.

[0158] If the start and end points of the holding pressure cycle are not directly recorded, they can be determined based on the changes in the slope of the pressure curve and the switching characteristics of the injection stage. The start point of holding pressure can be the inflection point where the pressure changes from a rapid increase to a slow change, and the end point of holding pressure can be the moment when the pressure begins to decay significantly or when the holding pressure signal of the injection molding machine ends.

[0159] Based on the pressure change data of each region, the pressure decay is compared to obtain the pressure maintenance state of each region.

[0160] In this step, the pressure decay data of each region are compared. The pressure decay comparison compares the pressure maintenance level, pressure decay rate, pressure maintenance integral, and deviation from the baseline.

[0161] For the region The pressure maintenance index can be calculated:

[0162] ,

[0163] in, Indicates the region The pressure maintenance index. Indicates the duration of the pressure holding phase. Indicates the weight of the pressure holding integral. This indicates the pressure decay weight. The first term represents the pressure holding capacity of the pressure holding section, and the second term represents the degree of pressure decay.

[0164] By comparing the current holding pressure maintenance index with the holding pressure maintenance benchmark in the molding reference state, the regional holding pressure maintenance state is obtained:

[0165] ,

[0166] in, Indicates the region The pressure holding state, Indicates the region The benchmark pressure maintenance index, This indicates the allowable deviation limit for maintaining pressure.

[0167] If the pressure holding state of the terminal mounting area is insufficient, and the flow deviation state shows that the area is lagging, it can be determined that there is strong evidence of insufficient filling and pressure holding in the area.

[0168] The temperature sequence is analyzed to identify the temperature decrease process, and temperature change data for each region is obtained.

[0169] In this step, the temperature decrease process during the cooling phase is identified from the temperature sequence. The temperature decrease process can be composed of temperature data from the start of cooling to the point before demolding. The temperature decrease slope, temperature decrease magnitude, temperature inflection point, and freezing determination point are extracted for each region.

[0170] For the region Temperature change data can be represented as:

[0171] ,

[0172] in, Indicates the region Temperature change data, Indicates the region At any moment rate of temperature decrease Indicates the region The freezing point is determined at the following time. Indicates the point at which cooling begins. This indicates the reference point when cooling is complete.

[0173] The rate of temperature decrease can be expressed as: ,

[0174] in, The larger the value, the faster the temperature drops in that area.

[0175] The freezing point can be determined based on the temperature threshold, the change in the temperature drop slope, or the material freezing window.

[0176] ,

[0177] in, Indicates the region The freezing point is determined at the following time. Indicates the region The freezing point is used to determine the temperature.

[0178] The freezing sequence was obtained by comparing the freezing order based on the temperature change data of each region.

[0179] In this step, the freezing judgment points for each area are compared to obtain the freezing sequence. The freezing sequence is used to characterize whether there is an abnormal freezing order between the box opening sealing area and the terminal mounting area.

[0180] area and region The time difference between freezing points can be expressed as:

[0181] ,

[0182] in, Indicates the region Relative to region Freeze time difference.

[0183] Compare the current freeze time difference with the freeze time difference in the forming reference state:

[0184] ,

[0185] in, This indicates the deviation of the freeze time difference from the result. Indicates the region and region The frozen baseline time difference between them.

[0186] If the sealing area of ​​the box opening freezes earlier than the terminal mounting area, the two areas may experience different shrinkage release times, resulting in a warping or displacement of the box opening after demolding. If the terminal mounting area freezes earlier than the sealing area of ​​the box opening, the stress distribution at the base of the terminal mounting post may couple with the shrinkage direction of the box opening, resulting in another type of warping or displacement.

[0187] The freeze sequence can be represented as: ,

[0188] in, Indicates the freeze sequence. Indicates the region and region The order of freezing is marked.

[0189] The pressure holding and freezing sequence are generated from the pressure and temperature sequences. They are obtained by extracting the pressure holding segment, comparing pressure decay, identifying the temperature drop process, and comparing the order of freezing. The pressure holding and freezing sequence includes the pressure holding index of each region and the markers for insufficient, normal, or high pressure holding. The freezing sequence includes the freezing judgment point, freezing time difference, and freezing order markers for each region. Their function is to provide a basis for judging insufficient pressure holding deviation and freezing imbalance deviation, respectively.

[0190] Zero-mean cooling perturbation identification is performed based on the temperature sequence to obtain the thermal response state.

[0191] This step is used to observe the temperature response differences in different regions by performing zoned cooling perturbations while keeping the total cooling capacity essentially constant, in order to identify the regional heat transfer status. This step avoids the regional control conflicts caused by traditional methods of uniformly lowering the mold temperature or uniformly extending the cooling time.

[0192] The temperature sequence is truncated for the cooling stage to obtain the cooling temperature sequence.

[0193] In this step, the cooling stage is extracted from the temperature sequence based on the molding baseline state and the current cycle temperature change characteristics. The cooling stage typically begins in the later stages of holding pressure or at the start of cooling and ends when the temperature stabilizes before demolding. The cooling temperature sequence is represented as follows:

[0194] ,

[0195] in, Represents a cooling temperature sequence. Represents a set of regions.

[0196] When capturing the cooling stage, temperature fluctuations during the initial injection filling phase and environmental disturbances after mold opening and demolding should be excluded. If there is sensor contact delay or external interference in the temperature sequence, filtering and outlier removal should be performed first, followed by the cooling stage capture.

[0197] A zero-mean cooling perturbation is applied to the cooling temperature sequence to obtain the temperature change before and after the perturbation.

[0198] In this step, a zero-mean cooling perturbation is applied to at least two cooling zones. A zero-mean cooling perturbation refers to increasing the cooling intensity of some cooling zones while decreasing the cooling intensity of others, so that the sum of the cooling intensity adjustments for all zones is zero or the constraint that the total cooling capacity does not increase is met.

[0199] Let the zone cooling intensity adjustment vector be: ,

[0200] in, This represents the zone cooling intensity adjustment vector. Indicates the region Adjustment amount of cooling intensity for the corresponding cooling zone.

[0201] Zero-mean cooling perturbation satisfies: ,

[0202] Alternatively, if the equipment has a cooling capacity limit, the following conditions may be met: ,

[0203] in, This indicates the upper limit of the total allowable cooling perturbation amplitude.

[0204] Before the perturbation is applied, the temperature change before the perturbation is calculated based on the cooling temperature sequence:

[0205] ,

[0206] in, Indicates the region The temperature change before the perturbation Indicates the starting point of the statistical window before perturbation. This indicates the end point of the statistical window before the perturbation.

[0207] After the perturbation is applied, the temperature change after the perturbation is calculated: ,

[0208] in, Indicates the region The amount of temperature change after perturbation. Indicates the starting point of the statistical window after perturbation. This indicates the end point of the statistical window after the perturbation.

[0209] The statistical window before and after the perturbation should be located within the same cooling stage and aligned with the molding reference state to avoid misjudgment due to different cycle positions. If actual production does not allow perturbation to be applied in every cycle, perturbation can be applied in the sampling cycle or trial molding cycle, and the identified thermal response state can be used for subsequent control cycles.

[0210] The temperature response difference is obtained by extracting the difference between the temperature change before and after the perturbation.

[0211] In this step, the difference in temperature change before and after the perturbation is extracted to obtain the difference in response of each region to the cooling perturbation: ,

[0212] in, Indicates the region Differences in temperature response.

[0213] To eliminate the effects of varying perturbation amplitudes, the normalized thermal response coefficient can also be calculated:

[0214] ,

[0215] in, Indicates the region The normalized thermal response coefficient, This represents a small correction amount used to avoid the denominator being zero. If the temperature drop increases significantly after the cooling intensity of a region increases, it indicates that the region is sensitive to cooling regulation; if the temperature response is weak after the cooling intensity changes, it may indicate that the region has high thermal resistance, insufficient heat conduction path, or is affected by the structural thickness.

[0216] The intensity of heat transfer is determined based on the difference in temperature response, and the thermal response state is obtained.

[0217] In this step, the heat transfer state of each region is determined based on the temperature response differences and the normalized thermal response coefficient. Thermal response states include strong response, normal response, weak response, and uneven response. When comparing the sealing area of ​​the housing and the terminal mounting area, if one area has a stronger response while the other has a weaker response, it indicates a difference in cooling efficiency between the two areas, which may lead to freezing imbalance.

[0218] The thermal response state can be expressed as: ,

[0219] in, Indicates the region thermal response state, Indicates the region The reference thermal response coefficient, This indicates the allowable deviation limit for thermal response.

[0220] The thermal response state is generated from the temperature sequence; it is obtained by extracting the cooling stage, applying zero-mean cooling perturbation, calculating the temperature change before and after the perturbation, extracting the temperature response difference, and determining the strength of heat transfer; it includes temperature response difference, normalized thermal response coefficient, and regional response label; its function is to provide evidence on the cooling and heat transfer side for judging regional freezing imbalance.

[0221] Based on the flow bias, pressure maintenance state, freezing time sequence and thermal response state, the cause of deviation is decoupled to obtain the insufficient pressure maintenance deviation or freezing imbalance deviation.

[0222] This step integrates and assesses flow propagation factors, pressure holding compensation factors, freezing sequence factors, and thermal response factors to differentiate the causes of dimensional deviations. Depending on the product weight, peak pressure, or single-point mold temperature, this step can identify the source of deviation under similar pressure or weight results.

[0223] The correlation between flow skewness and pressure maintenance state is determined to identify regions where pressure arrival is delayed and pressure maintenance is insufficient.

[0224] In this step, the pressure arrival lag region in the flow deviation state and the insufficient holding region in the pressure holding state are matched. If the same region simultaneously satisfies both pressure arrival lag and insufficient holding, it indicates that the region is affected by melt propagation hysteresis during the filling stage and does not receive sufficient pressure compensation during the holding stage, resulting in shrinkage deviation or insufficient size.

[0225] Set up a region The evidence value for insufficient warranty coverage is: ,

[0226] in, Indicates the region The evidence value for insufficient insurance coverage is insufficient. Indicates the region Does this indicate a lag in the arrival of pressure? Indicates the region Is this a marker indicating an area with insufficient pressure maintenance? Represents the skewness weights of the flow. This represents the weight of the pressure maintenance state.

[0227] when When the pressure reaches the insufficient holding pressure threshold, the area is identified as one where pressure arrival is delayed and holding pressure is insufficient. This determination applies to the terminal mounting area. If the terminal mounting area is far from the gate, the delayed pressure arrival and insufficient holding pressure can easily lead to shrinkage and displacement of the terminal mounting posts and deviation of the wiring hole position.

[0228] The deviation is attributed to the area where the pressure arrives late and the pressure holding is insufficient, thus obtaining the insufficient pressure holding deviation.

[0229] In this step, areas where pressure is delayed and pressure holding is insufficient are correlated with the locations of dimensional deviations in the housing. If the corresponding area is a terminal mounting area, and there are issues such as misalignment of mounting posts, insufficient wiring hole size, or localized shrinkage deviations, the deviation is attributed to insufficient pressure holding. If the corresponding area is a housing opening sealing area, and there are issues such as insufficient edge dimensions due to localized underpressure, this can also be classified as insufficient pressure holding deviation.

[0230] Insufficient filling and holding deviation includes the deviation area, deviation direction, deviation degree, and control object. The deviation area indicates that the dimensional deviation occurs in the sealing area of ​​the box opening or the terminal mounting area; the deviation direction indicates the direction of shrinkage offset or the direction of insufficient size; the deviation degree indicates the magnitude of the deviation relative to the qualified benchmark; the control object indicates that the injection speed, holding pressure, or holding pressure transmission status should be corrected first in the future.

[0231] The freezing time sequence and thermal response state are correlated and judged to identify regions where the freezing sequence is inconsistent and the thermal response is uneven.

[0232] In this step, abnormal freezing sequence is matched with regions of uneven response in the thermal response state. If there is an abnormal freezing sequence between the box opening sealing area and the terminal mounting area, and the thermal response states of the two are significantly different, it indicates that the dimensional deviation may be due to regional cooling differences and freezing imbalance, rather than simply insufficient filling or holding pressure.

[0233] Set up a region pair The evidence value for the frozen imbalance is: ,

[0234] in, Indicates the region and region Evidence value of the frozen imbalance between the two Indicates the region and region Are there any markers indicating inconsistent freezing order? Indicates the region and region Are there any markers indicating uneven thermal response? Indicates the frozen time series weights. This represents the weight of the thermal response state.

[0235] when When the freezing imbalance threshold is exceeded, the region is determined. and region There is inconsistency in the timing of freezing and uneven thermal response. This condition corresponds to the cooling difference between the sealing area of ​​the box opening and the terminal mounting area. This difference can easily cause a decrease in the coplanarity of the sealing edge of the box opening and directional warping after demolding.

[0236] The deviation was attributed to areas with inconsistent freezing times and uneven thermal responses, resulting in freezing imbalance deviation.

[0237] In this step, areas with inconsistent freezing times and uneven thermal responses are correlated with the locations of dimensional deviations after molding. If a coplanar deviation occurs in the box opening sealing area, and there is uneven thermal response and abnormal freezing sequence between the terminal mounting area and the box opening sealing area, the deviation is attributed to freezing imbalance deviation. If the dimensional shift in the terminal mounting area is accompanied by a change in the overall warping direction, this deviation can be classified as freezing imbalance deviation based on the freezing sequence and thermal response state.

[0238] Freezing imbalance deviations include imbalance region pairs, freezing sequence and direction, thermal response differences, warpage trends, and control targets. Imbalance region pairs represent combinations of regions experiencing freezing differences; freezing sequence and direction indicate which region freezes first and which freezes later; thermal response differences indicate the varying degrees of impact of cooling adjustments on different regions; warpage trends indicate the potential directional deformation of the box body after demolding; and control targets indicate that subsequent adjustments should prioritize correcting the cooling intensity of individual zones, rather than changing the overall holding pressure.

[0239] In one implementation, to avoid misjudgment when both types of biases exist simultaneously, the relative strength of evidence of insufficient coverage and evidence of freeze imbalance can be calculated:

[0240] ,

[0241] in, Indicates the type of deviation. This indicates the threshold for differences in causal evidence. If the case warrants further review, it can be confirmed by combining subsequent test results or data from the next cycle.

[0242] Insufficient charge / maintenance deviation or freezing imbalance deviation is generated by flow skewness, pressure maintenance state, freezing time sequence, and thermal response state; it is obtained through charge / maintenance side correlation judgment, freezing side correlation judgment, and deviation attribution; it includes deviation type, deviation area, deviation degree, control object, and attribution evidence; its function is to provide a clear direction for control quantity allocation.

[0243] The control quantity is allocated to the insufficient charge / protection deviation or the freezing imbalance deviation to obtain the charge / protection correction quantity or the limited cooling correction quantity.

[0244] This step is used to generate corresponding control correction amounts based on the cause of the deviation. If the deviation is an insufficient filling and holding deviation, correction amounts are preferentially allocated in the direction of injection speed and holding pressure; if the deviation is a freezing imbalance deviation, correction amounts are preferentially allocated in the direction of zoned cooling intensity, while satisfying the total cooling capacity constraint.

[0245] The degree of deviation is extracted from the insufficient filling and maintenance deviation to obtain the filling and maintenance deviation amount.

[0246] In this step, if the deviation type is insufficient charge / maintenance deviation, the degree of deviation is extracted from the insufficient charge / maintenance deviation. The charge / maintenance deviation can be composed of the degree of pressure lag, the degree of insufficient pressure maintenance, and the degree of dimensional deviation. For the terminal mounting area, the offset of the terminal mounting post position and the shrinkage deviation of the wiring hole can be extracted; for the box opening sealing area, the degree of local dimensional deficiency or local depression of the sealing edge can be extracted.

[0247] The charge / maintenance deviation can be expressed as: ,

[0248] in, Indicates the region The filling deviation amount, Indicates the region The time difference of arrival, Indicates the region The benchmark pressure maintenance index, Indicates the region The current pressure maintenance index, Indicates the region The current size detection value, Indicates the region Target size value, Indicates the allowable dimensional deviation. , , This represents the weighting coefficient.

[0249] If online dimensional inspection is not configured, the filling deviation is first obtained based on the process data, and then the deviation is corrected after offline dimensional inspection is completed.

[0250] The injection speed and holding pressure are allocated according to the filling and holding deviation to obtain the filling and holding correction amount.

[0251] In this step, the filling and holding deviation is converted into injection speed correction and holding pressure correction. The injection speed correction is used to improve melt arrival lag, and the holding pressure correction is used to improve insufficient holding pressure maintenance. To avoid excessive holding pressure near the gate area, the holding pressure should not be simply increased overall during control distribution, but should be adjusted in a controlled manner based on the deviation area and the holding pressure maintenance state.

[0252] The warranty warranty amount can be expressed as: ,

[0253] in, This indicates that the warranty has been fully restored. This indicates the injection speed correction amount. This indicates the pressure correction amount for holding pressure. This indicates the correction amount for the holding time.

[0254] In one embodiment, the injection speed correction and the holding pressure correction can be calculated as follows: ,

[0255] ,

[0256] in, This represents the injection speed correction factor. This represents the pressure holding correction factor. This represents the time difference deviation with positive lag. This indicates the deviation in pressure holding that is insufficient to maintain the required pressure.

[0257] If the pressure maintained in the sealing area of ​​the box opening is already too high, the upper limit of the pressure correction should be limited to prevent over-pressure holding and residual stress concentration in the sealing area. This limitation can be expressed as:

[0258] ,

[0259] in, Indicates the upper limit of the allowable holding pressure. This indicates the current holding pressure.

[0260] The degree of freezing imbalance is extracted to obtain the freezing deviation amount.

[0261] In this step, if the deviation type is freezing imbalance deviation, the freezing deviation amount is extracted from the freezing imbalance deviation. The freezing deviation amount can be composed of freezing time difference deviation, thermal response difference, and warpage dimension deviation. The freezing deviation amount is used to determine which areas need enhanced cooling, which areas need reduced cooling, and how the adjustment range should be distributed.

[0262] The freezing deviation can be expressed as:

[0263] ,

[0264] in, Indicates the region and region Freezing deviation between This indicates the deviation of the freeze time difference from the result. and Representing regions and region The normalized thermal response coefficient, This indicates the current warping or coplanarity deviation value. Indicates the target warping or coplanarity reference value. This indicates the allowable deviation limit for the freeze time difference. Indicates the allowable warpage deviation. , , This represents the weighting coefficient.

[0265] Based on the freezing deviation, the cooling intensity is allocated to each zone to obtain the limited cooling correction amount.

[0266] In this step, the freezing deviation is converted into an adjustment for the cooling intensity of different cooling zones. The cooling intensity of a zone is achieved through cooling water flow rate, cooling medium temperature, cooling valve opening, mold temperature controller zone setting, or cooling time allocation.

[0267] The limited cooling correction amount can be expressed as: ,

[0268] in, This indicates the limited cooling correction amount. Indicates the region The corresponding cooling intensity correction amount for the cooling zone.

[0269] This limited cooling correction satisfies the total cooling capacity constraint: ,

[0270] Or it satisfies: ,

[0271] in, Indicates the region Current cooling intensity, This indicates the lower limit of the total cooling capacity. This indicates the maximum total cooling capacity.

[0272] When the enclosure sealing area freezes earlier than the terminal mounting area, the cooling intensity of the enclosure sealing area can be reduced while the cooling intensity of the terminal mounting area can be increased, thus aligning the freezing times of the two areas. Conversely, when the terminal mounting area freezes earlier than the enclosure sealing area, the opposite distribution is applied. Due to the limited total cooling capacity, this adjustment will not simply increase the overall cooling load, thus avoiding a further widening of the freezing time difference due to enhanced global cooling.

[0273] The control quantity allocation is generated by the insufficient filling and holding deviation or the freezing imbalance deviation; it is obtained through deviation degree extraction, injection speed and holding pressure allocation, freezing deviation extraction, and zone cooling intensity allocation; the filling and holding correction quantity includes injection speed correction quantity, holding pressure correction quantity, and optional holding time correction quantity; the restricted zone cooling correction quantity includes zone cooling intensity adjustment quantity and total cooling capacity constraint; its function is to convert the cause decoupling result into executable control instructions.

[0274] Feedback correction is performed based on the filling and maintenance correction amount or the limited cooling correction amount to obtain the injection molding control result of the box body.

[0275] This step is used to apply the control correction amount to the injection molding process, and to verify the correction effect based on the detection data after execution, thus forming a closed-loop control result.

[0276] The control parameters for the current cycle are generated based on the maintenance correction amount or the limited cooling correction amount.

[0277] In this step, if a filling correction is obtained, the corrected injection speed, holding pressure, and holding time are generated based on the current injection molding machine control parameters. If a restricted cooling correction is obtained, the corrected zone cooling intensity, cooling medium flow rate, cooling valve opening, or cooling temperature setpoint are generated based on the current mold temperature controller or zone cooling control parameters.

[0278] The control parameters for the current cycle can be expressed as: ,

[0279] in, This indicates the updated control parameters. Indicates the current control parameters. This indicates the amount of full warranty or limited cold correction.

[0280] like Update the control parameters on the injection pressure-maintaining side;

[0281] like The control parameters are updated on the partition cooling side.

[0282] The injection molding process is executed based on the control parameters of the current cycle, and the area detection data after execution is obtained.

[0283] In this step, the updated control parameters are sent to the injection molding machine control system, mold temperature controller control system, or zoned cooling control system. During execution, pressure and temperature data from the box opening sealing area and terminal mounting area continue to be collected to obtain the area detection data after execution.

[0284] The executed regional detection data and the regional detection data have the same data structure, including regional pressure data, regional temperature data, sampling time, cycle number, and regional number.

[0285] The deviation of the regional detection data after execution is checked to obtain the check results.

[0286] In this step, the regional detection data after execution is re-aligned with periodic data, subjected to arrival time difference analysis, pressure holding and freezing analysis, and thermal response identification, and compared with the state before correction to obtain the verification results. The verification results include whether the flow skewness has been reduced, whether the pressure holding state has been improved, whether the freezing sequence has tended to the baseline, whether the thermal response state is balanced, whether the dimensional deviation has been reduced, and whether the control variables need to be further adjusted.

[0287] The review result can be expressed as: ,

[0288] in, This indicates the review result. This indicates the updated time difference of arrival deviation. This indicates the updated pressure maintenance index. This indicates the updated freeze time difference deviation result. This represents the updated thermal response coefficient. This indicates the updated size detection results. This indicates the updated warpage or coplanarity test results. A mark indicating whether the control is qualified.

[0289] Based on the review results, the control parameters for the current cycle are updated to obtain the control results for the injection molding of the box.

[0290] In this step, the control is assessed based on the verification results to determine if the target has been achieved. If the verification results show that the deviation has returned to the allowable range, the current control parameter is designated as a stable control parameter, and the box injection molding control results are output. If the verification results show that the deviation still exists, the next round of correction is generated based on the remaining deviation, and the control parameters are updated.

[0291] Control parameters can be updated recursively: ,

[0292] in, Indicates the first Wheel control parameters, Indicates the first Wheel control parameters, Indicates the first Wheel correction amount, Indicates the first The correction factor can be adaptively adjusted based on the review results. If the deviation improvement is significant, the correction magnitude should be reduced; if the deviation improvement is insufficient and the control boundary is not reached, the correction magnitude should be maintained or moderately increased.

[0293] The control results for injection molding of the box body include final control parameters, deviation type, deviation area, correction amount, verification status, pass / fail judgment, and subsequent control suggestions. These results can be output to the injection molding machine controller, production monitoring system, quality traceability system, or process parameter database.

[0294] The injection molding control results for the box body are derived from the combined effects of the filling and holding pressure correction or limited cooling correction, post-implementation area detection data, and verification results. These include stabilized injection holding pressure parameters, zone cooling parameters, deviation cause records, zone process status, dimensional control judgments, and feedback correction records. These results can guide parameter maintenance, anomaly alarms, quality traceability, and process optimization in subsequent injection molding cycles. This solution addresses the problem in existing technologies where it is difficult to distinguish the causes of dimensional deviations based on similar pressure and weight results, and resolves the issue of control conflicts easily arising between the box opening sealing edge and the terminal mounting area during global process corrections. Supported by a complete chain of zone detection, reference alignment, arrival time difference analysis, holding pressure and freeze analysis, thermal response identification, deviation cause decoupling, and control quantity allocation, this results in the simultaneous stability of the box opening sealing edge coplanarity and the terminal mounting position accuracy.

[0295] A specific embodiment of the present invention discloses an injection molding control system for a junction box plastic housing, such as... Figure 2 The system includes a benchmark extraction module, a period alignment module, an arrival analysis module, a pressure holding and freezing module, a perturbation identification module, a cause decoupling module, a control allocation module, and a feedback correction module.

[0296] The baseline extraction module acquires regional detection data of the junction box's plastic housing, performs baseline extraction on this data, and obtains the molding baseline state. The baseline extraction module communicates with the mold cavity pressure acquisition unit, mold temperature acquisition unit, injection molding machine controller, and quality inspection system. The baseline extraction module reads qualified cycle data, performs data filtering, noise processing, cycle normalization, and key time point extraction, and outputs the molding baseline state. This molding baseline state is then used by the cycle alignment module, arrival analysis module, pressure holding and freezing module, and feedback correction module.

[0297] The cycle alignment module aligns cycle data according to the molding reference state to obtain pressure and temperature sequences. The module reads the raw pressure and temperature data for the current cycle, retrieves the pressure and temperature reference time points from the molding reference state, performs time shifting, unifies sampling intervals, and aligns regional data, outputting the pressure and temperature sequences. This module ensures that the data used by subsequent analysis modules have a unified time reference and regional correspondence.

[0298] The arrival analysis module performs arrival time difference analysis based on the pressure sequence to obtain the flow skewness. It identifies the pressure rise start point in each region from the pressure sequence, calculates the arrival time difference between regions, compares the pressure sequence, and determines the time difference deviation and flow offset direction based on the forming reference state, outputting the flow skewness. The flow skewness is invoked by the cause decoupling module to determine insufficient filling / maintenance deviations.

[0299] The pressure holding and freezing module is used to perform pressure holding and freezing analysis on pressure and temperature sequences, obtaining the pressure holding maintenance state and freezing time sequence. The module extracts the pressure holding segment from the pressure sequence and analyzes the pressure decay; it identifies the temperature decrease process from the temperature sequence and compares the freezing sequence, outputting the pressure holding maintenance state and freezing time sequence. The pressure holding maintenance state and flow skewness are used together for attributing insufficient pressure holding, while the freezing time sequence and thermal response state are used together for attributing freezing imbalance.

[0300] The perturbation identification module is used to identify zero-mean cooling perturbations based on the temperature sequence to obtain the thermal response state. The module extracts the cooling temperature sequence from the temperature sequence, generates or reads zero-mean cooling perturbation execution information, calculates the temperature change before and after the perturbation, extracts the temperature response difference, determines the strength of heat transfer, and outputs the thermal response state. This thermal response state is then used by the causal decoupling module to determine regional cooling differences.

[0301] The cause decoupling module is used to decouple the causes of deviations based on flow skewness, pressure holding state, freezing sequence, and thermal response state, to obtain insufficient pressure holding deviations or freezing imbalance deviations. The module performs correlation judgments between flow skewness and pressure holding state to determine if there are regions where pressure arrival is delayed and pressure holding is insufficient; it also performs correlation judgments between freezing sequence and thermal response state to determine if there are regions where freezing order is inconsistent and thermal response is uneven; based on the correlation judgment results, it performs deviation attribution and outputs the deviation type and deviation region.

[0302] The control allocation module is used to allocate control quantities for insufficient charge / maintenance deviations or freeze imbalance deviations, obtaining either a charge / maintenance correction amount or a restricted cooling correction amount. When the deviation type is insufficient charge / maintenance, the control allocation module extracts the charge / maintenance deviation amount and generates correction amounts for injection speed and holding pressure; when the deviation type is freeze imbalance, it extracts the freeze deviation amount and generates a zoned cooling intensity correction amount that satisfies the total cooling capacity constraint. The correction amounts output by the control allocation module are used by the feedback correction module.

[0303] The feedback correction module is used to perform feedback correction based on the filling and maintenance correction amount or the limited cooling correction amount, to obtain the control result of the box injection molding. The feedback correction module generates control parameters based on the correction amount, sends the control parameters to the injection molding machine or zoned cooling equipment, receives the area detection data after execution, performs deviation verification, and updates the control parameters based on the verification results. The feedback correction module outputs the final box injection molding control result and writes the control result into the process database or quality traceability system.

[0304] Embodiments of the present invention have been presented and described. It will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

[0305] Those skilled in the art should understand that the embodiments of the present invention can be implemented using a pure hardware architecture, a pure software architecture, or an integrated hardware and software architecture. The present invention can be prepared as a computer program product, which can be stored in various non-volatile computer-readable storage media, including but not limited to solid-state drives, flash memory chips, mobile storage devices, optical discs, cloud storage servers, and other standardized storage media, and is not limited to traditional storage media.

[0306] The above description of embodiments of the present invention is provided. Without departing from the embodiments and broad aspects of the present invention, those skilled in the art can make data modifications and method changes based on this description in specific operations. The appended claims are intended to include all data modifications and method changes that do not depart from the embodiments of the present invention.

[0307] Based on the foregoing description in conjunction with the accompanying drawings, those skilled in the art will understand that the embodiments of this application can be implemented by software programs. Therefore, this application also provides a computer-readable storage medium. This computer-readable storage medium stores computer-readable instructions, which, when executed by a processor, implement the method described above in conjunction with the accompanying drawings.

[0308] Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, or by hardware. The technical solutions described above, in essence or in terms of their contribution to the prior art, can be embodied in the form of a software product, which can be stored in a computer-readable storage medium, such as... Disks, optical disks, etc., including a number of instructions to cause a computer device to perform the methods described in the various embodiments or some parts of the embodiments.

[0309] It should be noted that the operations of the method described in the accompanying drawings are in a specific order, but this does not require or imply that these operations must be performed in that specific order, or that all of the shown operations must be performed to achieve the desired result. On the contrary, the steps depicted in the flowchart can be executed in a different order. Additionally or alternatively, certain steps may be omitted, multiple steps may be integrated into a single step, and / or a single step may be broken down into multiple steps.

[0310] It should be understood that when the terms "first," "second," "third," and "fourth," etc., are used in the claims, specification, and drawings of this application, they are used to distinguish different objects, not to describe a specific order. The terms "comprising" and "including" as used in the specification and claims of this application indicate the presence of the described features, units, steps, operations, elements, and / or components, but do not exclude the presence or addition of other features, units, steps, operations, elements, components, and / or sets.

[0311] It should be understood that the terminology used in this specification is for the purpose of describing particular embodiments and is not intended to limit the application. As used in this specification and claims, the singular forms “a” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. It should be further understood that the term “and / or” as used in this specification and claims refers to any combination of one or more of the associated listed items, and all possible combinations thereof.

[0312] The embodiments of this application are as described above, but the content described is merely an example for the purpose of understanding this application and is not intended to limit the scope or application scenarios of this application. Any person skilled in the art described in this application may make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in this application, but the scope of patent protection of this application shall still be determined by the scope defined in the appended claims.

Claims

1. A method for controlling the injection molding of a junction box plastic housing, characterized in that, include: Obtain the area detection data of the junction box plastic body, and perform benchmark extraction on the area detection data to obtain the molding benchmark state; Based on the molding reference state, periodic data alignment is performed to obtain pressure and temperature sequences; Based on the pressure sequence, time-of-arrival analysis was performed to obtain the flow skewness; The pressure and temperature sequences were subjected to pressure holding and freezing analysis to obtain the pressure holding state and freezing time sequence. Zero-mean cooling perturbation identification is performed based on the temperature sequence to obtain the thermal response state; Based on the aforementioned flow bias state, pressure maintenance state, freezing sequence, and thermal response state, the cause of deviation is decoupled to obtain the insufficient pressure maintenance deviation or freezing imbalance deviation. The control amount is allocated to the insufficient charge / protection deviation or the freezing imbalance deviation to obtain the charge / protection correction amount or the limited cooling correction amount; Feedback correction is performed based on the filling and maintenance correction amount or the limited cooling correction amount to obtain the injection molding control result of the box body.

2. The injection molding control method according to claim 1, characterized in that, Based on the molding reference state, periodic data alignment is performed to obtain pressure and temperature sequences, including: The reference time points of the forming reference state are extracted to obtain the pressure reference time point and the temperature reference time point; Using the pressure and temperature reference times as constraints, the pressure and temperature data in the regional detection data are time-shifted and the sampling interval is unified to obtain aligned pressure and temperature data. The aligned pressure and temperature data are then processed by region correspondence to obtain pressure and temperature sequences.

3. The injection molding control method according to claim 1, characterized in that, Based on the pressure sequence, arrival time difference analysis is performed to obtain the flow skewness, including: The pressure sequence is analyzed to identify the pressure rise segment, and the pressure rise starting point of each region is obtained. The time difference between each region is calculated based on the pressure rise point in each region. By comparing the time differences of arrival between the aforementioned regions in a directional manner, the pressure sequence relationship is obtained; Based on the arrival time difference and pressure sequence relationship between the regions, skewness determination is performed to obtain the flow skewness.

4. The injection molding control method according to claim 1, characterized in that, The pressure and temperature sequences were subjected to pressure-holding freeze analysis to obtain the pressure-holding maintenance state and the freeze time sequence, including: The pressure sequence is truncated to a holding pressure segment to obtain the holding pressure change data for each region; Based on the pressure change data of each region, the pressure decay is compared to obtain the pressure maintenance state of each region. The temperature sequence is analyzed to identify the temperature decrease process, and temperature change data for each region is obtained. The freezing sequence is obtained by comparing the freezing order based on the temperature change data of each region.

5. The injection molding control method according to claim 1, characterized in that, Based on the temperature sequence, zero-mean cooling perturbation identification is performed to obtain the thermal response state, including: The temperature sequence is truncated during the cooling stage to obtain a cooling temperature sequence; A zero-mean cooling perturbation is applied to the cooling temperature sequence to obtain the temperature change before and after the perturbation. The temperature response difference is obtained by extracting the difference between the temperature change before and after the perturbation. The strength of heat transfer is determined based on the temperature response difference to obtain the thermal response state.

6. The injection molding control method according to claim 1, characterized in that, Based on the aforementioned flow bias, pressure maintenance state, freezing sequence, and thermal response state, the causes of deviations are decoupled to obtain insufficient charge / maintenance deviations or freezing imbalance deviations, including: The correlation between the flow deviation state and the pressure holding state is determined to identify the region where the pressure arrival is delayed and the pressure holding is insufficient. Based on the region where the pressure arrives late and the pressure holding is insufficient, the deviation is attributed to the insufficient pressure holding deviation. The freezing sequence and thermal response state are correlated and judged to identify regions where the freezing order is inconsistent and the thermal response is uneven. The deviation is attributed to the regions where the freezing order is inconsistent and the thermal response is uneven, resulting in freezing imbalance deviation.

7. The injection molding control method according to claim 1, characterized in that, The control quantity allocation for the aforementioned insufficient charge / protection deviation or freezing imbalance deviation yields the charge / protection correction quantity or the limited cooling correction quantity, including: The degree of inadequate charging deviation is extracted to obtain the charging deviation amount; Based on the filling and holding deviation, the injection speed and holding pressure are allocated to obtain the filling and holding correction amount; The degree of the freezing imbalance deviation is extracted to obtain the freezing deviation amount; Based on the freezing deviation, the cooling intensity is allocated to each zone to obtain the limited cooling correction amount.

8. The injection molding control method according to claim 1, characterized in that, Feedback correction is performed based on the aforementioned filling and maintenance correction amount or limited cooling correction amount to obtain the injection molding control results of the box body, including: The control parameters for the current cycle are generated based on the aforementioned maintenance correction amount or limited cooling correction amount. The injection molding process is executed based on the control parameters of the current cycle to obtain the area detection data after the execution. The deviation of the region detection data after execution is checked to obtain the check result; Based on the verification results, the control parameters for the current cycle are updated to obtain the injection molding control results for the box body.

9. The injection molding control method according to claim 3, characterized in that, Based on the arrival time difference and pressure sequence relationship between the aforementioned regions, skewness determination is performed to obtain the flow skewness, including: The time difference of arrival between the regions and the forming reference state are compared to obtain the time difference deviation result; Based on the pressure sequence, the time difference deviation results are marked in direction to obtain the pressure arrival advance region and the pressure arrival lag region; By performing region correspondence determination on the pressure arrival advance region and the pressure arrival lag region, the flow offset direction is obtained; Based on the flow offset direction and time difference deviation results, the skewness is confirmed to obtain the flow skewness.

10. A control system for injection molding a junction box plastic housing, characterized in that, include: The reference extraction module is used to acquire the area detection data of the junction box plastic body, and to perform reference extraction on the area detection data to obtain the molding reference state; The period alignment module is used to align periodic data according to the forming reference state to obtain pressure sequence and temperature sequence; The arrival analysis module is used to perform arrival time difference analysis based on the pressure sequence to obtain the flow skewness. The pressure holding and freezing module is used to perform pressure holding and freezing analysis on the pressure sequence and temperature sequence to obtain the pressure holding state and freezing time sequence. The perturbation identification module is used to identify zero-mean cooling perturbations based on the temperature sequence to obtain the thermal response state; The cause decoupling module is used to decouple the causes of deviations based on the flow bias, pressure maintenance state, freezing sequence and thermal response state to obtain the insufficient charge-maintenance deviation or freezing imbalance deviation. The control allocation module is used to allocate control amounts to the insufficient charge / protection deviation or the freezing imbalance deviation to obtain the charge / protection correction amount or the limited cooling correction amount. The feedback correction module is used to perform feedback correction based on the filling and maintenance correction amount or the limited cooling correction amount to obtain the injection molding control result of the box body.

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