Injection molding collaborative control method and device based on molding timing and mold state assimilation

Abstract

The application relates to the technical field of injection molding control, and discloses an injection molding cooperative control method and device based on assimilation of molding time sequence and mold state. The application aims to solve the problem that the fixed machine action rhythm in the existing control system is disengaged from the actual thermal state of the mold, leading to unstable molding quality in continuous production. In the application, a reference time sequence is generated by acquiring a reference physical state and action time; actual system time of state data jump is collected in an actual period, compared with the reference time sequence to obtain a translation time difference value, and the injection molding machine action time table is translated as a whole; subsequently, power execution and waterway temperature control instructions are synchronously issued based on the translated time axis; finally, demolding deviation data is collected in the mold opening stage to update the reference of the next period.

Description

Technical Field

[0001] This invention relates to the field of injection molding control technology, and more specifically, to an injection molding collaborative control method and device based on the assimilation of molding sequence and mold state. Background Technology

[0002] The injection molding collaborative control system is the core hub for ensuring the processing quality and production cycle of plastic products. In the current injection molding field, the mechanical motion system of the injection molding machine and the water circuit temperature control system of the mold typically employ independent control architectures. Specifically, the injection molding machine controller generally relies on pre-set fixed time intervals or stroke positions to sequentially trigger mechanical actions such as injection advancement and pressure holding switching; while the mold water circuit temperature control system mainly relies on a single temperature target value for independent cyclic adjustment. The two operate independently in terms of data and commands, primarily relying on technicians to perform static parameter matching during the start-up and commissioning phase.

[0003] However, in real-world scenarios involving long-term, high-volume continuous production, the actual flow rate of the molten plastic within the mold cavity and the cooling and solidification process dynamically drift due to the inevitable cumulative heat buildup in the mold body. Because existing control systems employ isolated and rigid fixed action cycles, they cannot perceive and adapt to the actual physical changes within the mold, easily leading to a severe disconnect between the injection molding machine's mechanical intervention actions and the timing of cooling medium temperature reduction and the actual physical evolution of the plastic within the mold cavity. This disconnect between control timing and the actual thermal state of the mold often causes uneven local shrinkage of the melt or residual stress within the mold cavity, making it difficult for the equipment to maintain stable and consistent molding quality during long-term continuous production. Summary of the Invention

[0004] In view of the aforementioned existing problems, the present invention is proposed.

[0005] Therefore, the present invention provides an injection molding collaborative control method and device based on the assimilation of molding timing and mold state, which solves the problem of unstable molding quality during continuous production caused by the disconnect between the fixed machine action cycle and the actual thermal state of the mold in the existing control system.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] This invention provides a collaborative control method for injection molding based on the assimilation of molding timing and mold state, executed by a control device, which includes the following steps:

[0008] S1. Obtain the reference physical state data inside the mold cavity and the reference machine action time of the injection molding machine, and bind the reference physical state data with the reference machine action time to generate a reference time sequence.

[0009] S2. During the actual injection molding cycle, synchronously collect the actual system time when the actual physical state data of the injection molding machine and the reference physical state data change abruptly.

[0010] S3. Compare the actual system time with the reference state time node in the reference time series to obtain the translation time difference, and superimpose the translation time difference as a translation parameter onto the control time axis to realize the overall translation of the injection molding machine action time schedule.

[0011] S4. Based on the translated control time axis, synchronously send coordinated control commands to the power actuator of the injection molding machine and the mold water circuit temperature control system;

[0012] S5. Collect demolding deviation data during the mold opening stage and convert it into basic correction coefficients. Then, pre-add the basic correction coefficients to the reference time series of the next cycle.

[0013] As a preferred embodiment of the injection molding collaborative control method based on the assimilation of molding timing and mold state described in this invention, S1 specifically includes:

[0014] The temperature acquisition device and the pressure acquisition device are respectively deployed inside the mold cavity. Based on the synchronous clock inside the same controller, the temperature data and pressure data inside the mold cavity are acquired, as well as the motion position data and driving pressure data of the injection molding machine are acquired.

[0015] During the baseline molding test phase, the baseline system time of machine actions corresponding to each process stage within the injection molding cycle is recorded; the pressure rise curve and temperature rise curve inside the mold cavity are recorded simultaneously within the corresponding baseline system time.

[0016] From the pressure rise curve and the temperature rise curve, extract the reference time when the pressure data shows a jump rise state and the reference time when the temperature data shows a jump rise state, respectively, and use them as the reference state time node.

[0017] The reference state time node is bound to the reference system time on the time axis to generate a reference time sequence that associates machine actions with the physical state inside the mold.

[0018] As a preferred embodiment of the injection molding collaborative control method based on the assimilation of molding timing and mold state described in this invention, S3 specifically includes:

[0019] In the actual injection molding cycle, the pressure data inside the mold cavity is monitored and acquired as the actual physical state data. If a sudden increase in pressure data is detected, the corresponding actual system time is recorded. The difference between the actual system time and the corresponding pressure jump moment in the reference time series is superimposed on the control time axis as a translation time difference, so that the trigger time of the preset subsequent pressure holding switching action and pressure holding decreasing action are both shifted in time along with the translation time difference.

[0020] As a preferred embodiment of the injection molding collaborative control method based on the assimilation of molding timing and mold state described in this invention, S4 specifically includes:

[0021] According to the control timeline after translation, an action switching signal is sent to the power actuator to control the injection molding machine to switch to the pressure holding state at the time node after translation; within the same time threshold when the action switching signal is sent, an opening adjustment signal is sent to the mold water circuit temperature control system according to the control timeline after translation, so that the machine pressure holding and mold cooling are triggered synchronously at the time node after translation.

[0022] As a preferred embodiment of the injection molding collaborative control method based on the assimilation of molding timing and mold state described in this invention, step S5 specifically includes:

[0023] At the mold opening moment of the current injection molding cycle, the pressure zeroing time inside the mold cavity and the demolding surface temperature of the product are obtained; based on the reference time series, the time deviation between the pressure zeroing time and the reference zeroing time, and the temperature deviation between the demolding surface temperature and the reference temperature are calculated respectively; the time deviation and the temperature deviation are used as the demolding deviation data, and converted according to the preset weight to calculate the basic correction coefficient; before the start of the next injection molding cycle, the basic correction coefficient is superimposed on the reference time series to update the comparison benchmark for the next cycle.

[0024] As a preferred embodiment of the injection molding collaborative control method based on the assimilation of molding timing and mold state described in this invention, step S4, which involves issuing instructions to the power actuator, further includes:

[0025] If the translation time difference is greater than a preset lag time threshold, extract the out-of-range time value that exceeds the lag time threshold;

[0026] Based on the aforementioned out-of-range time value, the number of stepped pressurization stages and the single-stage pressure increment are calculated through a preset compensation mapping model.

[0027] While performing the overall time shift, an additional stepped pressurization signal containing the stepped pressurization levels and single-stage pressure increments is sent to the power actuator;

[0028] The injection molding machine is controlled to provide progressively increasing holding pressure during the holding period after translation, and the maximum holding pressure after the increase is limited to not exceeding the system's preset anti-bulging safety threshold.

[0029] As a preferred embodiment of the injection molding collaborative control method based on the assimilation of molding timing and mold state described in this invention, the step S4, which sends an opening adjustment signal to the mold water circuit temperature control system, includes the following mode switching mechanism:

[0030] If the basic correction coefficient calculated during the mold opening stage shows a unidirectional increasing trend within a preset number of injection cycles, then during the process of sending the opening adjustment signal to the mold water circuit temperature control system, the opening maintenance mode is converted to the variable adjustment mode, and the mold water circuit temperature control system is controlled to perform pulse-like adjustment of alternating opening sizes, so that the cooling medium flowing into the mold presents a wave-like variable flow scouring state.

[0031] As a preferred embodiment of the injection molding collaborative control method based on the assimilation of molding timing and mold state described in this invention, step S2 further includes:

[0032] If the temperature difference between the actual temperature of the mold cavity and the reference temperature within the reference time series is greater than a preset safety threshold, the reference time series is locked, suspending its participation in the calculation of translation parameters. The temperature difference value is converted into a direct heating control signal to control the built-in heating module of the mold to heat. Heating continues until the actual temperature of the mold cavity rises back to within the preset safety threshold, at which point the lock on the reference time series is released, thereby resuming the calculation of the overall time translation.

[0033] The present invention also provides an injection molding collaborative control device based on the assimilation of molding timing and mold state, for executing the above method, specifically including:

[0034] The physical sensing terminal includes temperature and pressure sensors deployed inside the mold cavity, and motion transmitters deployed on the side of the injection molding machine.

[0035] The collaborative execution terminal includes the power actuator of the injection molding machine, as well as the water circuit regulating valve and heating module in the mold water circuit temperature control system;

[0036] Data acquisition interface and control output interface;

[0037] The main controller is connected to the physical sensing terminal through the data acquisition interface and to the collaborative execution terminal through the control output interface;

[0038] The main controller integrates a time synchronization module, which unifies the mold cavity status data collected by the physical sensing terminal and the mechanical motion data of the injection molding machine onto the same central control time axis.

[0039] The main controller further includes a memory and a processor. When the processor runs a computer-readable program stored in the memory, it executes the injection molding collaborative control method based on the assimilation of molding sequence and mold state as described in any one of claims 1 to 9, based on the time reference of the time synchronization module.

[0040] The beneficial effects of this invention are as follows: This invention achieves the timing matching of the mechanical action of the machine and the actual physical progress of the mold cavity, ensuring the synchronous triggering of the machine and mold actions, and adapts to the heat accumulation during continuous operation of the equipment through the dynamic evolution of the benchmark, thus maintaining the consistency of long-cycle production. Attached Figure Description

[0041] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 A schematic diagram of the basic control main flow of the injection molding collaborative control method based on the assimilation of molding timing and mold state provided in the embodiments of the present invention;

[0043] Figure 2 This is a tree diagram for the multi-condition adaptive takeover logic judgment provided in the embodiments of the present invention;

[0044] Figure 3 This is a schematic diagram of the system architecture of the injection molding collaborative control device provided in an embodiment of the present invention. Detailed Implementation

[0045] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0046] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0047] Secondly, the term "one embodiment" or "example" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the invention. An embodiment appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that mutually excludes other embodiments.

[0048] Example 1

[0049] Reference Figure 1 This is the first embodiment of the present invention. This embodiment provides an injection molding collaborative control method and apparatus based on the assimilation of molding timing and mold state. As the basic and core implementation method of the present invention, it is used to realize basic molding timing assimilation and cross-system action collaboration, including the following steps:

[0050] S1. Obtain the reference physical state data inside the mold cavity and the reference machine action time of the injection molding machine, bind the reference physical state data and the reference machine action time to generate a reference time series.

[0051] Temperature and pressure acquisition devices are deployed inside the mold cavity respectively. Based on the synchronous clock inside the same controller, temperature and pressure data inside the mold cavity are acquired, as well as the motion position and driving pressure data of the injection molding machine are acquired.

[0052] During the baseline molding test phase, the baseline system time of machine actions corresponding to each process stage within the injection molding cycle is recorded; the pressure rise curve and temperature rise curve inside the mold cavity are recorded simultaneously within the corresponding baseline system time.

[0053] From the pressure rise curve and the temperature rise curve, extract the reference time when the pressure data shows a jump and the reference time when the temperature data shows a jump and use them as the reference state time node.

[0054] By binding the baseline state time node with the baseline system time on the time axis, a baseline time sequence is generated that relates the machine actions and the physical state inside the mold.

[0055] In the initial benchmark molding test phase of the system's initial operation, a benchmark time series needs to be constructed to establish a standard reference for subsequent coordinated control. In terms of hardware layout, temperature and pressure acquisition devices are deployed at the end of the plastic melt flow within the mold cavity and at corners prone to stress concentration, ensuring that the acquired physical states effectively reflect the actual filling quality. Simultaneously, transmitters for acquiring motion positions and driving pressures are configured at the injection molding machine end. During the standard trial molding process, the controller accurately records the benchmark system time occurring at each process stage of the injection molding machine, from injection propulsion and pressure holding to cooling and shaping. During this period, the pressure rise curve and temperature rise curve inside the mold cavity are recorded synchronously. Subsequently, the controller extracts the absolute moments when the pressure reaches its peak and the absolute moments when the temperature jumps from these curves, using these as key benchmark state time nodes.

[0056] In the underlying recognition algorithm of the system, the specific logic for determining a sudden upward trend in data is as follows: The rate of change of pressure and temperature data per unit time (i.e., the first derivative of the data curve) is calculated in real time. When this rate of change exceeds a preset slope threshold (in specific engineering settings, this is combined with material properties and sensor sampling rate; for example, the slope threshold for pressure data is set to 10 MPa / s, and the slope threshold for temperature data is set to 50℃ / s), a sudden change is determined. From the perspective of injection molding physics, when the high-temperature plastic melt wavefront instantaneously contacts the probe inside the mold cavity, or when the melt instantly fills the cavity and begins the compaction process, the temperature and pressure signals, which were originally at the environmental baseline and trending gently, will suddenly rise sharply within an extremely short window of a few milliseconds to tens of milliseconds. By identifying and capturing the initial moment when the slope exceeds the threshold, the system can extremely accurately lock the true physical boundary of the melt flow, effectively eliminating the slow numerical drift caused by conventional environmental interference.

[0057] Ultimately, the system binds these state nodes, which represent the progress of physical evolution, to the baseline system time of machine actions at the time axis level, generating a baseline time series that associates mechanical actions with internal physical states, and stores it in internal memory as a static benchmark for subsequent mass production comparison.

[0058] S2. During the actual injection molding cycle, the actual system time when the actual physical state data of the injection molding machine and the reference physical state data change abruptly are synchronously collected.

[0059] S3. Compare the actual system time with the reference state time node in the reference time series to obtain the translation time difference. Use the translation time difference as a translation parameter to superimpose it on the control time axis to realize the overall translation of the injection molding machine action time schedule.

[0060] S3 specifically includes: In the actual injection molding cycle, monitoring and acquiring the pressure data inside the mold cavity as actual physical state data; if the pressure data shows a sudden increase, recording the corresponding actual system time; and superimposing the difference between the actual system time and the corresponding pressure jump moment in the reference time series as a translation time difference onto the control time axis, so that the trigger time of the preset subsequent pressure holding switching action and pressure holding decrease action are both shifted in time along with the translation time difference.

[0061] In the mass production phase, the system initiates real-time assimilation adjustment based on a pre-stored baseline time series. Since heat inevitably accumulates in the mold's metal body during continuous operation, the overall temperature increase in the mold cavity leads to a faster melt filling speed, causing the actual physical state to deviate from the set expectations. Therefore, the system continuously monitors the mold cavity pressure data during the injection cycle. Once a sudden increase in pressure data is detected, the corresponding actual system time is immediately captured. After capturing this actual system time, to quantify the degree of deviation of the actual physical state from expectations, this embodiment does not change the preset injection pressure or speed amplitude, but instead calculates the translation time difference using a specific mathematical model. The calculation formula is as follows:

[0062]

[0063] In the formula:

[0064] Characterizes the translation time difference;

[0065] Characterizes the actual system time during which the pressure captured by monitoring shows a sudden increase;

[0066] Characterizes the reference time of the corresponding pressure jump recorded in the reference time series.

[0067] During the overall calculation process, the system directly subtracts the reference time scalar from the real-time acquired time scalar. This formula not only calculates the absolute value of the time deviation, but more importantly, establishes the evolution trend of the physical state through the mathematical symbol of the result: when... When the result is positive, it indicates that the actual system time is later than the reference time, representing a lag in the melt flow inside the mold; when A negative result indicates that the actual system time is earlier than the reference time, signifying that the current melt flow velocity has already advanced. The controller uses the calculated positive and negative values... It is directly added or subtracted as a parameter to the central control time axis of the controller, so as to achieve the same-scale translation of the timing of subsequent actions.

[0068] The system identifies this difference as the thermodynamic timing advance (or lag) of the current equipment and adds it as a whole compensation parameter to the central control time axis of the controller. Through this operation, the trigger times of the injection molding machine's preset subsequent pressure holding switching action and pressure holding reduction action are all shifted by the same amplitude as this shift time difference, so that the rhythm of the machine's mechanical actions actively adapts to the actual flow evolution of the melt in the mold.

[0069] S4. Based on the translated control time axis, synchronously send coordinated control commands to the power actuator of the injection molding machine and the mold water circuit temperature control system;

[0070] According to the control time axis after translation, an action switching signal is sent to the power actuator to control the injection molding machine to switch to the pressure holding state at the time node after translation; within the same time threshold when the action switching signal is sent, according to the control time axis after translation, an opening adjustment signal is sent to the mold water circuit temperature control system to make the machine pressure holding and mold cooling trigger synchronously at the time node after translation.

[0071] After the overall translation of the control time axis is confirmed to be effective, the system seamlessly transitions to the cross-system physical coordination response stage. To address issues such as the disconnect between machine actions and water circuit temperature control in conventional equipment, leading to action discrepancies and increased residual stress in the product, this embodiment establishes a cross-system forced triggering rule. The system sends an action switching signal to the injection molding machine's power actuator according to the revised translation time axis, causing the equipment to enter the pressure-holding state at the precise time node after the translation. Simultaneously, within the same time threshold window when this action switching signal is issued, the system synchronously sends an opening adjustment command to the electromagnetic regulating valve of the mold water circuit temperature control system based on the same translation time axis. In specific engineering settings, considering the communication cycle of the control bus and the electrical response characteristics of the electromagnetic valve, the same time threshold essentially refers to the maximum allowed time difference window for the synchronous issuance of the injection molding machine action signal and the mold water circuit signal. This time difference window is typically set between 5 and 15 milliseconds. For example, if the system is set to 10 milliseconds, it means that within 10 milliseconds after the controller sends the pressure-holding current signal to the servo driver, the water circuit opening signal must be forcibly issued. This signal transmission mechanism establishes a strong correlation between the mechanical pressure-holding action of the screw maintaining density and the physical cooling action of the cooling medium carrying away heat at the control layer, ensuring that the two major systems of the machine and the mold can achieve synchronous intervention at the same correction node after the timing drift occurs.

[0072] S5. Collect demolding deviation data during the mold opening stage and convert it into basic correction coefficients. Then, pre-add the basic correction coefficients to the reference time series of the next cycle.

[0073] At the mold opening moment of the current injection cycle, the pressure zeroing time inside the mold cavity and the demolding surface temperature of the product are obtained; based on the reference time series, the time deviation between the pressure zeroing time and the reference zeroing time, and the temperature deviation between the demolding surface temperature and the reference temperature are calculated respectively; the time deviation and temperature deviation are used as demolding deviation data, and converted according to the preset weight to calculate the basic correction coefficient; before the start of the next injection cycle, the basic correction coefficient is superimposed on the reference time series to update the comparison benchmark for the next cycle.

[0074] When the machine-mold coordinated action is completed and the current injection molding cycle enters the mold opening and demolding stage, the system initiates a benchmark update program through a closed-loop feedback mechanism to endow the equipment with the ability to adapt to long-term environmental evolution. At the moment the mold is fully open, the system acquires the time it takes for the mold cavity pressure to return to zero and the actual surface temperature of the demolded product. These two parameters can effectively characterize whether the product exhibits thermal balance abnormalities such as sticking to the mold or limited cooling.

[0075] Since the extracted pressure zeroing time (dimension: time) and the demolding surface temperature (dimension: temperature) belong to completely different physical dimensions, they cannot be directly added mathematically. To eliminate the dimensional barrier, the system employs an algorithm combining relative deviation normalization and weighted summation to transform them into a unified dimensionless basic correction coefficient. The specific calculation formula is as follows:

[0076]

[0077] In the formula:

[0078] The basic correction coefficient (dimensionless comprehensive relative deviation ratio) is derived from the characterization calculation.

[0079] Characterizes the time it takes for the pressure to return to zero, as actually measured in the current cycle;

[0080] Characterizes the baseline zeroing time recorded in the baseline time series;

[0081] Characterizes the actual demolding surface temperature currently measured;

[0082] Characterizing the reference temperature in the reference time series;

[0083] Characterizes the preset time weight ratio;

[0084] Characterizes the preset temperature weighting ratio (satisfying) ).

[0085] In the overall calculation and mapping process, the system first calculates the time deviation and temperature deviation separately, and then divides the absolute deviation by their respective reference values ​​(i.e., and This division operation is crucial; it transforms the absolute deviation with physical units into a relative percentage deviation in pure numerical form, thus fundamentally eliminating the physical dimensions of time and temperature. Subsequently, the system utilizes dimensionless weighting parameters. and (In specific engineering settings, to highlight thermodynamic characteristics, It is usually set to 0.3. (Set to 0.7) is multiplied by the normalized relative deviation and summed. The final comprehensive scalar is obtained. This is a dimensionless fundamental correction coefficient. This coefficient directly characterizes the comprehensive relative magnitude of the current overall system thermal equilibrium state deviating from the ideal reference (e.g., This represents a 5% deviation in the overall thermal state of the system, thus providing a dimensionless input reference value for subsequent linear proportional gain mapping.

[0086] Before preparing to close the mold and execute the next injection cycle, the system initiates a baseline update program with safety boundary constraints. First, addressing the dimension conversion issue, the system employs linear proportional gain mapping logic to convert the dimensionless basic correction coefficient into a specific time compensation amount (in milliseconds). The specific conversion logic is as follows: the time compensation amount equals the product of the basic correction coefficient and the built-in timing conversion gain parameter. In actual engineering debugging, this gain parameter is factory calibrated based on the equipment's thermal inertia and timing response characteristics (for example, setting the conversion gain to 1000 milliseconds / unit coefficient, meaning that if the system deviates by 1%, a coefficient of 0.01 corresponds to a compensation of 10 milliseconds). Continuing the previous example, if the basic correction coefficient calculated for the current cycle is 0.05 (i.e., a deviation of 5%), the system directly calculates the current time compensation amount as 0.05 × 1000 = 50 milliseconds through this linear mapping. Secondly, since the impact of thermal drift on the injection molding cycle is global, this time compensation amount is not only used to correct a certain isolated node, but is used as a global time offset amount, which is uniformly superimposed and corrected to all machine action nodes and physical state nodes in the base time series.

[0087] Furthermore, to prevent control divergence due to error accumulation or sudden external interference during infinite consecutive updates, the system sets a global safety boundary threshold for cumulative drift in the update algorithm (e.g., limiting the updated reference deviation to no more than ±10% of the initial static reference), as well as the maximum allowable step size for a single update. Before each reference superposition, the system performs an out-of-bounds check: if the calculated single time compensation exceeds the step size limit, or the updated cumulative total drift reaches the safety boundary threshold, the system determines that the current cycle is under abnormal interference and triggers a safety rollback mechanism—refusing to execute the current dynamic update and maintaining the reference sequence of the previous cycle unchanged; if multiple consecutive cycles trigger an out-of-bounds alarm, the system forcibly clears all accumulated dynamic compensation and rolls back to the static initial reference time sequence initially generated by the system. Through this update mechanism that integrates global mapping, boundary limiting, and abnormal rollback, the reference sequence used for comparison not only achieves an intelligent transformation from static to dynamic, but also eliminates system crashes caused by thermal drift accumulation from the underlying algorithm, ensuring that the device maintains highly reliable assimilation calculation and collaborative control during long-term operation.

[0088] Example 2

[0089] Reference Figure 2 This is the second embodiment of the present invention. This embodiment provides an injection molding collaborative control method based on the assimilation of molding timing and mold state. In addition to the basic control process of Embodiment 1, an adaptive takeover control logic covering multiple working conditions throughout the entire cycle is introduced, specifically including:

[0090] S2 also includes: if the temperature difference between the actual temperature of the mold cavity and the reference temperature in the reference time series is greater than a preset safety threshold, then the reference time series is locked, so that the reference time series is suspended from participating in the calculation of the translation parameters; the temperature difference value is converted into a heating direct control signal to control the heating module built into the mold to heat; after heating continues until the actual temperature of the mold cavity rises back to within the preset safety threshold, the locking state of the reference time series is released, thereby resuming the calculation of the overall time translation.

[0091] The system is configured with a high-priority initial startup interception mechanism. In the initial stage of equipment power-on and operation, the mold has not yet established thermal equilibrium. At this time, the injected molten plastic is prone to rapid cooling, leading to a surge in filling resistance or even flow stagnation. If the system directly calculates time differences and shifts timing based on sensor data fluctuating due to unsteady conditions, it will disrupt the injection molding machine's timing sequence. Therefore, during the phase of synchronously collecting actual physical state data, the system prioritizes state assessment interception based on a low-level mathematical discriminant formula, which is:

[0092]

[0093] In the formula:

[0094] Characterizes the reference demolding temperature pre-stored in the reference time series;

[0095] Characterizes the actual temperature of the demolded surface read by the sensor during the current cycle;

[0096] The numerical value representing the temperature difference calculated from both methods;

[0097] Characterizes the preset safe temperature difference threshold within the system.

[0098] During the calculation, the controller must strictly subtract the actual temperature from the reference temperature to ensure that this algorithm branch is triggered only for cold operation (actual temperature is much lower than the reference temperature). Once the calculated temperature difference value is obtained... Positive and greater than the preset value (In specific engineering settings, Typically set between 20°C and 30°C (e.g., 25°C), the system determines that the cold-weather interception condition has been triggered, and then locks the reference time series, causing the reference time series to suspend participation in all subsequent translation parameter calculation processes.

[0099] Upon entering this forced takeover state, the master control program suspends the current execution privileges of the assimilation algorithm and reverts the calculated temperature difference values. This is converted into a pulse width modulation (PWM) duty cycle signal, driving the heating module (such as a heating resistance wire) built into the mold to perform high-power heating. During this period, the system continuously monitors the actual demolding surface temperature until the temperature gradually rises back up, causing the calculated temperature difference to decrease and fall back to the preset safety threshold. Within this range, once the fallback condition is met, the system automatically releases the lock on the baseline time series, thereby restoring and activating the subsequent normal overall time shift calculation process. This underlying interception and forced heating mechanism gives the system the ability to smoothly transition from the initial unsteady state to the normal mass production state, fundamentally ensuring that all subsequent assimilation calculations are based within the safe boundary where the mold has formed an initial thermal equilibrium.

[0100] The instructions issued to the power actuator in S4 also include:

[0101] If the translation time difference is greater than the preset lag time threshold, extract the out-of-range time value that exceeds the lag time threshold;

[0102] Based on the out-of-range time value, the number of stepped pressurization stages and the single-stage pressure increment are calculated through a preset compensation mapping model.

[0103] While performing the overall time shift, an additional stepped pressurization signal containing the number of stepped pressurization stages and the single-stage pressure increment is sent to the power actuator;

[0104] The injection molding machine is controlled to provide progressively increasing holding pressure during the holding period after translation, and the maximum holding pressure after the increase is limited to not exceeding the system's preset anti-bulging safety threshold.

[0105] When the mold temperature rises back to within the safe threshold, the system releases the blockade and allows normal overall time translation calculation. For the calculation results within a single cycle, the system is configured with two mutually exclusive abnormal intervention branches. One is a stepped pressurization branch for deep shrinkage conditions. When filling thick-walled or large-volume injection molded parts, although the outer surface of the part has cooled and solidified in contact with the mold surface, the internal melt core remains in a high-temperature molten state. During the cooling and solidification process, significant volume shrinkage and inward collapse occur, resulting in a significant delay in the time it takes for the surface pressure probe to detect pressure jumps. Therefore, the system sets a corresponding trigger judgment: if the translation time difference is greater than the preset lag time threshold, an additional stepped pressurization signal is sent to the power actuator while performing the overall time translation, controlling the injection molding machine to provide progressively increasing holding pressure during the holding pressure period after translation. In specific parameter settings, the lag time threshold is typically set between 0.5 and 1.0 seconds, for example, +0.8 seconds. If the calculated translation time difference reaches +0.8 seconds, the system determines that simply relying on the backward translation of the time axis is insufficient to compensate for the volume shrinkage void inside the product.

[0106] Therefore, while shifting the action sequence backward, the system further extracts the portion of the shift time difference exceeding the lag time threshold as the out-of-tolerance time value, and uses a built-in compensation mapping model to forward convert it into specific stepped pressurization levels and single-stage pressure increments. In this compensation mapping model, the system adopts a logic combining segmented lookup and proportional gain: for the stepped pressurization levels, the system performs discretization matching based on the segmented interval to which the out-of-tolerance time value belongs (for example, setting the pressurization level to increase discretely by 1 level for every 0.2 seconds increase in out-of-tolerance time, with a maximum limit of 5 levels); for the single-stage pressure increment, the system multiplies the out-of-tolerance time value by a preset pressure compensation gain coefficient to obtain a continuous pressure compensation value (for example, calculating 5MPa). Subsequently, the system outputs a stepped pressurization signal containing the above parameters to the hydraulic proportional valve, causing the screw to provide progressively increasing propulsion pressure within the pressure holding range after the shift. Meanwhile, the maximum holding pressure after the increase is forcibly controlled by the system's underlying logic to not exceed the system's preset anti-bulging mold safety threshold. Through safe and controlled continuous mechanical external force, the outer material is prompted to fill the volume of the internal shrinkage area, thereby completely overcoming the molding defects caused by deep shrinkage while ensuring the absolute safety of the equipment.

[0107] The operation of issuing commands to the mold water circuit temperature control system in S4 includes the following timing change mechanism:

[0108] If the translation time difference is less than the preset advance time threshold, the operation of synchronous signal transmission is cancelled. Before sending the action switching signal, the opening adjustment signal is sent in advance by a preset pipeline flow delay time to compensate for the physical delivery time difference of the cooling medium.

[0109] Another single-cycle abnormal intervention branch, mutually exclusive with the aforementioned delayed intervention, is the action separation branch targeting the thin-walled fluid delay. In high-speed ultra-thin-wall injection molding scenarios, the production cycle is extremely short due to the extremely rapid cooling of the product. At this time, the heat accumulated in the mold causes the melt to instantly fill the mold cavity, and the calculated translation time difference often shows a significant lead. However, although the signal sent by the electronic control system is within milliseconds, the cooling medium needs to undergo tens to hundreds of milliseconds of physical transport time to flow to the mold cavity in water pipes that are several meters long. If the synchronous triggering rule in the aforementioned embodiment is still adhered to, the ultra-thin-walled product will have already missed the optimal cooling opportunity by the time the cooling water arrives. To address this, the system sets up a reverse triggering mechanism: if the translation time difference is less than a preset lead time threshold, the synchronous signal sending operation is canceled, and an opening adjustment signal is sent in advance by a preset pipeline flow delay time before sending the action switching signal to compensate for the physical transport time difference of the cooling medium. In specific engineering settings, the lead time threshold is typically set to a negative range of -0.1 to -0.3 seconds (e.g., -0.2 seconds), while the pipeline flow delay time is determined by actual measurement using a flow meter based on the length of the water path, and is usually set between 100 and 300 milliseconds (e.g., 200 milliseconds). When the system calculates that the translation time difference reaches -0.2 seconds, the system changes the control rules, issuing the opening adjustment command for the mold water path 200 milliseconds in advance. This time advance in the control algorithm offsets the fluid dynamics delivery delay, ensuring that the pre-departed cooling water flows into the mold cavity to remove heat precisely at the moment the servo motor engages the pressure-holding action.

[0110] S4 sends an opening adjustment signal to the mold water circuit temperature control system, which includes the following mode switching mechanism:

[0111] If the basic correction coefficient calculated during the mold opening stage shows a unidirectional increasing trend within a preset number of injection cycles, the opening maintenance mode will be converted to a variable adjustment mode during the process of sending the opening adjustment signal to the mold water circuit temperature control system. This will control the mold water circuit temperature control system to perform pulse-like adjustment of alternating opening sizes, so that the cooling medium flowing into the mold presents a wave-like variable flow scouring state.

[0112] Independent of the aforementioned single-cycle mutual exclusion judgment, the system continuously runs a cross-cycle macroscopic thermal balance monitoring branch in the background. During long-term, continuous, high-intensity production, heat accumulation zones easily form on the inner wall boundaries of the mold's water channels, which are difficult to dissipate effectively with conventional constant flow, leading to a cumulative increase in the overall heat of the equipment. The system employs a long-term monitoring mechanism based on discrete sequence comparison: it monitors and stores the basic correction coefficients calculated at each mold opening stage. Internally, the system uses continuous inequalities to determine whether the sequence exhibits a unidirectional increasing trend. The determination logic is as follows:

[0113]

[0114] In the formula:

[0115] This represents the latest injection molding cycle number;

[0116] Characterizes the basic correction coefficient calculated for the current cycle;

[0117] The threshold value representing the preset number of injection cycle spans (in specific control settings, ...) It is usually set to a positive integer between 3 and 5, for example, set to 3).

[0118] At the end of each injection cycle, the system will update the coefficients. Push onto the stack, and then extract the previous items one by one. A strict one-way comparison is performed on the correction coefficients for each historical period. Only when this is continuous Only when the correction coefficients of each cycle form a strictly monotonically increasing sequence does the system formally establish the judgment result that the basic correction coefficients show a unidirectional increasing trend in the underlying algorithm. Once this condition is met, the system immediately switches from the opening maintenance mode to the variable adjustment mode while sending the opening adjustment signal to the mold water circuit temperature control system. This controls the mold water circuit temperature control system to perform pulse-like adjustments with alternating opening sizes, causing the cooling medium flowing into the mold to exhibit a wave-like variable flow scouring state. In specific control settings, the preset number of injection cycles is usually set to 3 to 5 consecutive cycles, for example, 3 consecutive cycles. When the system finds that the basic correction coefficient, obtained by weighting time deviation and temperature deviation, is greater than the previous value in 3 consecutive calculations, it objectively determines that the current constant cooling water flow rate can no longer suppress the heat accumulation inside the mold. When the system determines that the constant cooling water flow rate is constrained by thermal resistance, it stops using the fixed opening strategy and instead sends high and low alternating square wave pulse signals, causing the valve to be in a high-frequency switching state between fully open and partially closed. This operation causes a drastic change in water pressure within the pipes, prompting the cooling medium entering the mold cavity water passages to form a wave flow with physical impact. The turbulence effect generated by the variable flow rate breaks down the heat-adhesive boundary layer on the inner wall of the water passages, thereby effectively eliminating the cumulative heat island effect inside the mold and maintaining the long-term stability of the production environment.

[0119] Example 3

[0120] Reference Figure 3 This is the third embodiment of the present invention. This embodiment provides an injection molding collaborative control device based on the assimilation of molding timing and mold state, serving as the physical execution carrier for the control methods of Embodiments 1 and 2, specifically including:

[0121] The physical sensing terminal includes temperature and pressure sensors deployed inside the mold cavity, and motion transmitters deployed on the side of the injection molding machine.

[0122] The collaborative execution terminal includes the power actuator of the injection molding machine, as well as the water circuit regulating valve and heating module in the mold water circuit temperature control system;

[0123] Data acquisition interface and control output interface;

[0124] The main controller connects to the physical sensing terminal via a data acquisition interface and to the collaborative execution terminal via a control output interface.

[0125] The main controller integrates a time synchronization module, which unifies the mold cavity status data collected by the physical sensing terminal and the mechanical motion data of the injection molding machine onto the same central control time axis.

[0126] The main controller also includes a memory and a processor. When the processor runs a computer-readable program stored in the memory, it executes the injection molding collaborative control method based on the assimilation of molding timing and mold state as described in any one of claims 1 to 9, based on the time reference of the time synchronization module.

[0127] The data acquisition interface, at the physical level, is responsible for receiving front-end information. Its inputs are connected to infrared temperature probes and piezoelectric pressure probes pre-embedded inside the mold cavity, as well as displacement and pressure transmitters installed on the screw tail and injection cylinder of the injection molding machine. It receives data reflecting changes in the physical state of the mold cavity and the mechanical movements of the injection molding machine in real time at a high-frequency sampling rate. The control output interface, at the physical level, is responsible for triggering the execution of back-end actions. Its outputs are electrically connected to the servo motor driver and hydraulic proportional valve in the injection molding machine's power actuators, as well as the cooling water electromagnetic regulating valve and built-in heating module in the mold's water temperature control system. This allows for the synchronous transmission of power signals to all actuators.

[0128] The main controller, acting as the central nervous system of the control device, establishes industrial bus-level communication connections with both the data acquisition interface and the control output interface. In terms of hardware architecture, the main controller includes a processor (such as an industrial-grade microprocessor or a programmable logic controller (PLC)) and a memory coupled to it. The memory (such as non-volatile flash memory) stores compiled computer-readable program code that integrates the aforementioned molding timing assimilation algorithm and multi-condition adaptive takeover control logic. During actual operation, the processor reads the program code from the memory, driving the data acquisition interface to continuously acquire pressure jumps and temperature data of the mold cavity. Internally, the processor constructs the reference time series, calculates the translation time difference, performs cross-cycle weighted updates of the basic correction coefficient, and determines whether mutually exclusive conditions such as delayed step pressurization, advanced water supply, mold thermal accumulation wave erosion, or forced cold-machine interception are triggered. Finally, based on the calculation and judgment results, the processor precisely issues coordinated control commands with strict timing binding to the injection molding machine's power actuator and water temperature control system through the control output interface, thereby fully executing all the injection molding coordinated control methods based on the assimilation of molding timing and mold state as described in Examples 1 and 2. Through the high degree of integration of the above-mentioned hardware and software, the device in this embodiment completely breaks down the information silos of the traditional injection molding machine and mold temperature controller at the physical level, realizing millisecond-level data interaction and action coordination at the underlying level.

[0129] In summary, this invention achieves timing matching between the mechanical actions of the machine and the actual physical progress of the mold cavity, ensuring synchronous triggering of the machine and mold actions, and adapts to the heat accumulation during continuous operation of the equipment through the dynamic evolution of the benchmark, thus maintaining the consistency of long-cycle production.

[0130] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A collaborative control method for injection molding based on the assimilation of molding timing and mold state, characterized in that, Performed by a control device, the process includes the following steps: S1. Obtain the reference physical state data inside the mold cavity and the reference machine action time of the injection molding machine, and bind the reference physical state data with the reference machine action time to generate a reference time sequence. S2. During the actual injection molding cycle, synchronously collect the actual system time when the actual physical state data of the injection molding machine and the reference physical state data change abruptly. S3. Compare the actual system time with the reference state time node in the reference time series to obtain the translation time difference, and superimpose the translation time difference as a translation parameter onto the control time axis to realize the overall translation of the injection molding machine action time schedule. S4. Based on the translated control time axis, synchronously send coordinated control commands to the power actuator of the injection molding machine and the mold water circuit temperature control system; S5. Collect demolding deviation data during the mold opening stage and convert it into basic correction coefficients. Then, pre-add the basic correction coefficients to the reference time series of the next cycle.

2. The injection molding collaborative control method based on the assimilation of molding timing and mold state according to claim 1, characterized in that, S1 specifically includes: Temperature and pressure acquisition devices are deployed inside the mold cavity respectively. Based on the synchronous clock inside the same controller, temperature and pressure data inside the mold cavity are acquired, as well as the motion position and driving pressure data of the injection molding machine are acquired. During the baseline molding test phase, the baseline system time of machine actions corresponding to each process stage within the injection molding cycle is recorded; the pressure rise curve and temperature rise curve inside the mold cavity are recorded simultaneously within the corresponding baseline system time. From the pressure rise curve and the temperature rise curve, extract the reference time when the pressure data shows a jump rise state and the reference time when the temperature data shows a jump rise state, respectively, and use them as the reference state time node. The reference state time node is bound to the reference system time on the time axis to generate a reference time sequence that associates machine actions with the physical state inside the mold.

3. The injection molding collaborative control method based on the assimilation of molding timing and mold state according to claim 1, characterized in that, S3 specifically includes: In the actual injection molding cycle, the pressure data inside the mold cavity is monitored and acquired as the actual physical state data. If the pressure data shows a sudden increase, the difference between the actual system time and the corresponding reference time in the reference time series is calculated and superimposed on the control time axis as the translation time difference. This ensures that the trigger time of the preset subsequent pressure holding switching action and pressure holding decreasing action are both shifted along with the translation time difference.

4. The injection molding collaborative control method based on the assimilation of molding timing and mold state according to claim 1, characterized in that, S4 specifically includes: According to the control timeline after translation, an action switching signal is sent to the power actuator to control the injection molding machine to switch to the pressure holding state at the time node after translation; within the same time threshold when the action switching signal is sent, an opening adjustment signal is sent to the mold water circuit temperature control system according to the control timeline after translation, so that the machine pressure holding and mold cooling are triggered synchronously at the time node after translation.

5. The injection molding collaborative control method based on the assimilation of molding timing and mold state according to claim 1, characterized in that, S5 specifically includes: At the mold opening moment of the current injection molding cycle, the pressure zeroing time inside the mold cavity and the demolding surface temperature of the product are obtained; based on the reference time series, the time deviation between the pressure zeroing time and the reference zeroing time, and the temperature deviation between the demolding surface temperature and the reference temperature are calculated respectively; the time deviation and the temperature deviation are used as the demolding deviation data, and converted according to the preset weight to calculate the basic correction coefficient; before the start of the next injection molding cycle, the basic correction coefficient is superimposed on the reference time series to update the comparison benchmark for the next cycle.

6. The injection molding collaborative control method based on the assimilation of molding timing and mold state according to claim 4, characterized in that, The step S4, which involves issuing instructions to the power actuator, further includes: If the translation time difference is greater than a preset lag time threshold, extract the out-of-range time value that exceeds the lag time threshold; Based on the aforementioned out-of-range time value, the number of stepped pressurization stages and the single-stage pressure increment are calculated through a preset compensation mapping model. While performing the overall time shift, an additional stepped pressurization signal containing the stepped pressurization levels and single-stage pressure increments is sent to the power actuator; The injection molding machine is controlled to provide progressively increasing holding pressure during the holding period after translation, and the maximum holding pressure after the increase is limited to not exceeding the system's preset anti-bulging safety threshold.

7. The injection molding collaborative control method based on the assimilation of molding timing and mold state according to claim 4, characterized in that, The operation of issuing commands to the mold water circuit temperature control system in S4 includes the following timing change mechanism: If the translation time difference is less than the preset advance time threshold, the operation of synchronous signal transmission is cancelled. Before sending the action switching signal, the opening adjustment signal is sent in advance by a preset pipeline flow delay time to compensate for the physical delivery time difference of the cooling medium.

8. The injection molding collaborative control method based on the assimilation of molding timing and mold state according to claim 4, characterized in that, The S4 step of sending an opening adjustment signal to the mold water circuit temperature control system includes the following mode switching mechanism: If the basic correction coefficient calculated during the mold opening stage shows a unidirectional increasing trend within a preset number of injection cycles, then during the process of sending the opening adjustment signal to the mold water circuit temperature control system, the opening maintenance mode is converted to the variable adjustment mode, and the mold water circuit temperature control system is controlled to perform pulse-like adjustment of alternating opening sizes, so that the cooling medium flowing into the mold presents a wave-like variable flow scouring state.

9. The injection molding collaborative control method based on the assimilation of molding timing and mold state according to claim 1, characterized in that, S2 further includes: If the temperature difference between the actual temperature of the mold cavity and the reference temperature within the reference time series is greater than a preset safety threshold, the reference time series is locked, suspending its participation in the calculation of translation parameters. The temperature difference value is converted into a direct heating control signal to control the built-in heating module of the mold to heat. Heating continues until the actual temperature of the mold cavity rises back to within the preset safety threshold, at which point the lock on the reference time series is released, thereby resuming the calculation of the overall time translation.

10. An injection molding collaborative control device based on the assimilation of molding timing and mold state, characterized in that, include: The physical sensing terminal includes temperature and pressure sensors deployed inside the mold cavity, and motion transmitters deployed on the side of the injection molding machine. The collaborative execution terminal includes the power actuator of the injection molding machine, as well as the water circuit regulating valve and heating module in the mold water circuit temperature control system; Data acquisition interface and control output interface; The main controller is connected to the physical sensing terminal through the data acquisition interface and to the collaborative execution terminal through the control output interface; The main controller integrates a time synchronization module, which unifies the mold cavity status data collected by the physical sensing terminal and the mechanical motion data of the injection molding machine onto the same central control time axis. The main controller further includes a memory and a processor. When the processor runs a computer-readable program stored in the memory, it executes the injection molding collaborative control method based on the assimilation of molding sequence and mold state as described in any one of claims 1 to 9, based on the time reference of the time synchronization module.

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