Injection mold hot runner control method and system based on porous shunt pressure equalization

Abstract

The application provides a hot runner control method and system based on porous shunt pressure equalization for injection mold, and relates to the technical field of injection molding. The method comprises the following steps: injecting molten plastic into a primary distribution cavity to form a collected melt; allowing the collected melt to pass through multiple groups of shunt holes arranged between the primary distribution cavity and a secondary equalization cavity, so as to convert the collected melt into multiple shunt melts; introducing the multiple shunt melts into the secondary equalization cavity; mixing and remelting the multiple shunt melts in the secondary equalization cavity to form a homogeneous melt; and arranging multiple dynamic pressure collection points at specific geometric positions of the secondary equalization cavity on the basis of forming the homogeneous melt, wherein the specific geometric positions at least include a near-gate side inner wall center point, a far-gate side inner wall center point, and two side wall monitoring points symmetrically distributed along the radial direction. The application can balance the glue discharge pressure of an odd number of hot nozzles, avoid the core deviation caused by pressure imbalance, and improve the mold delivery efficiency.

Description

Technical Field

[0001] This invention relates to the field of injection molding technology, and in particular to a method and system for controlling the hot runner of injection molds based on multi-hole flow pressure equalization. Background Technology

[0002] In the field of injection molding, the hot runner system is a core component for achieving high-precision and high-efficiency injection molding. The uniformity of melt distribution directly determines the product molding quality and mold life. Especially in injection molding scenarios with multiple gates and complex cavity profiles (such as 12V lead-acid battery case), the pressure balance control of the hot runner is crucial. Such products typically require an odd number of hot runners, such as a structure with 7 hot runners corresponding to 6 single chambers and 7 partitions, to meet the requirements of integrity and consistency in cavity filling.

[0003] Existing injection mold hot runner control methods generally adopt the traditional distribution logic based on binary splitting (1 to 2, 2 to 4, 4 to 8). This logic relies on symmetrical runner branch design to achieve melt distribution and generally has the following technical defects: the inherent design makes it unable to adapt to the pressure equalization distribution requirements of an odd number of hot nozzles.

[0004] This defect causes the following key problems: Because an odd number of hot nozzles cannot obtain equal melt pressure and flow rate through binary flow distribution, the mold core, with its thin and tall structure, will shift due to lateral pressure imbalance, ultimately leading to mold filling failure and product molding defects (such as short shots). Moreover, to compensate for the pressure imbalance, repeated adjustments to the hot nozzle flow channel size are required for trial molding and calibration, which not only increases the number of trial moldings and production costs but also prolongs the product delivery cycle, seriously affecting the mold supplier's production efficiency and profit margin. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method and system for controlling the hot runner of injection molds based on multi-hole flow pressure equalization, which can realize the discharge pressure balance of an odd number of hot nozzles, avoid mold core displacement caused by pressure imbalance, improve mold delivery efficiency, and reduce production costs.

[0006] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0007] A first aspect is a hot runner control method for injection molds based on multi-hole flow distribution pressure equalization, the method comprising:

[0008] Molten plastic is injected into the primary distribution chamber to form a pooled melt; the pooled melt is then passed through a multi-component flow orifice located between the primary distribution chamber and the secondary equalization chamber, thereby transforming the pooled melt into a multi-streamed melt.

[0009] The multi-stream melt is introduced into the secondary equalization chamber, where it is mixed and remelted to form a homogeneous melt.

[0010] Based on the formation of a homogeneous melt, multiple dynamic pressure acquisition points are arranged at specific geometric locations in the secondary equalization cavity. The specific geometric locations include at least the center point of the inner wall near the gate, the center point of the inner wall far from the gate, and two side wall monitoring points symmetrically distributed along the radial direction. Real-time pressure data of each dynamic pressure acquisition point are collected simultaneously.

[0011] Based on real-time pressure data, a three-dimensional pressure field isosurface volume characterizing the transient pressure distribution within a secondary equilibrium cavity is constructed.

[0012] Calculate the volume change rate of the three-dimensional pressure field isosurface and generate an adaptive pressure adjustment coefficient based on the volume change rate;

[0013] The homogeneous melt is led to the pressure equalization output chamber, and an adjustable pressure setting is performed on the homogeneous melt in the pressure equalization output chamber based on the adaptive pressure adjustment coefficient, thereby obtaining a pressure-equalized melt.

[0014] By connecting multiple output channels of the pressure equalization output chamber, the pressure-equalizing melt is synchronously distributed to an odd number of hot nozzles of the mold.

[0015] Furthermore, molten plastic is injected into the primary distribution chamber to form a collected melt; the collected melt is then passed through a multi-component flow orifice located between the primary distribution chamber and the secondary equalization chamber, thereby transforming the collected melt into a multi-streamed melt, including:

[0016] Molten plastic from the injection molding machine nozzle is introduced into the primary distribution chamber through the main flow path, so that the molten plastic forms an initial aggregate melt in the primary distribution chamber;

[0017] The pressure in the primary distribution chamber is monitored in real time, and the chamber pressure is compared with the preset inlet pressure threshold to obtain the comparison result;

[0018] Based on the comparison results, the melt flow rate of the main channel is dynamically adjusted so that the initial collected melt is stabilized within a preset pressure range, forming a pressure-stable collected melt.

[0019] The pressure-stable collected melt is driven to flow through a multi-component flow orifice, wherein the multi-component flow orifice is arranged in an asymmetrical but flow-balanced manner through the partition between the primary distribution chamber and the secondary equalization chamber.

[0020] Through the throttling and guiding effect of the multi-component flow orifice, the pressure-stable aggregated melt is uniformly divided into multiple streams of melt with similar flow rates and pressures.

[0021] Furthermore, the multi-stream melt is introduced into a secondary equalization chamber, where it is mixed and remelted to form a homogeneous melt, comprising:

[0022] Multiple streams of melt with similar flow rates and pressures from the multi-component flow orifice are guided into the inlet region of the secondary equalization chamber at a preset inlet angle.

[0023] Within the inlet area, a flow guiding structure is set up to cause the multi-stream split melts to initially converge and exchange momentum, thereby forming an initial converged melt.

[0024] The primary flow of the initial confluence of melts into the main mixing zone of the secondary equalization chamber is driven. Within the main mixing zone, the turbulence effect generated by the geometry of the chamber promotes thorough shear mixing and heat exchange between the multiple melt streams.

[0025] Real-time monitoring of melt temperature and viscosity within the main mixing zone ensures it remains within the preset remelting process window;

[0026] Under the condition of meeting the remelting process window, the fully mixed melt completes the final thermal homogenization and molecular chain reconstruction at the end of the main mixing zone, forming a homogeneous melt with uniform physical properties.

[0027] Furthermore, based on the formation of a homogeneous melt, multiple dynamic pressure acquisition points are arranged at specific geometric locations within the secondary equalization cavity. These specific geometric locations include at least the center point of the inner wall near the gate, the center point of the inner wall far from the gate, and two sidewall monitoring points symmetrically distributed radially. Real-time pressure data from each dynamic pressure acquisition point is collected synchronously, including:

[0028] On the inner wall of the secondary equalization chamber, a set of key sampling points for characterizing dynamic pressure distribution are selected; the key sampling points include at least a proximal point near the center of the inner wall on the side close to the inlet of the diversion hole, a distal point far from the center of the inner wall on the side far from the inlet of the diversion hole, and a pair of lateral points located on both sides of the chamber and symmetrically distributed with respect to the central axis of the chamber.

[0029] High-response miniature pressure sensors are installed at each key acquisition point to construct a multi-point pressure sensing array that matches the cavity structure.

[0030] When the homogeneous melt flows through the secondary equalization chamber, the multi-point pressure sensing array is activated simultaneously.

[0031] The instantaneous melt pressure signal at each key acquisition point is collected in real time and synchronously through a multi-point pressure sensor array.

[0032] The instantaneous pressure signals collected at each point are synchronized to generate a set of original datasets of cavity dynamic pressure with spatiotemporal correlation.

[0033] Furthermore, based on real-time pressure data, a three-dimensional pressure field isosurface volume characterizing the transient pressure distribution within the secondary equilibrium cavity is constructed, including:

[0034] Obtain the raw dataset of dynamic pressure in the cavity;

[0035] Based on the spatial coordinates of key acquisition points, spatial interpolation calculations are performed on the instantaneous pressure signals in the raw dynamic pressure dataset of the cavity to generate a spatial pressure distribution function covering the entire inner cavity of the secondary equalization cavity.

[0036] Based on the spatial pressure distribution function, a transient pressure field point cloud reflecting the pressure values ​​at various points within the cavity at the same moment is reconstructed in a three-dimensional coordinate system.

[0037] Isosurface extraction and surface fitting are performed on the transient pressure field point cloud to construct a three-dimensional pressure field isosurface volume that characterizes the transient pressure distribution in the current injection molding cycle.

[0038] Furthermore, the volume change rate of the three-dimensional pressure field isosurface is calculated, and an adaptive pressure adjustment coefficient is generated based on the volume change rate, including:

[0039] Obtain the three-dimensional pressure field contour volume at multiple consecutive moments within the current injection molding cycle;

[0040] Calculate the instantaneous volume of the three-dimensional pressure field isosurface at each consecutive moment, and generate a set of volume values ​​arranged in a time series;

[0041] Based on the volume values ​​arranged in a time series, the ratio of the change in volume values ​​at adjacent times to the time interval is calculated, thereby obtaining the volume change rate sequence.

[0042] Extract characteristic rates of change that characterize the dynamic evolution trend of the pressure field from the volume change rate sequence;

[0043] The characteristic rate of change is input into a preset adjustment coefficient mapping model. Through the nonlinear transformation of the preset adjustment coefficient mapping model, an adaptive pressure adjustment coefficient is generated to adjust the working state of the pressure equalization output chamber.

[0044] Furthermore, the homogeneous melt is led to the pressure equalization output chamber, and based on an adaptive pressure adjustment coefficient, an adjustable pressure setting is performed on the homogeneous melt within the pressure equalization output chamber to obtain a pressure-equalized melt, including:

[0045] The corresponding pressure tuning parameters are calculated based on the adaptive pressure regulation coefficient.

[0046] The homogeneous melt is introduced into the pressure equalization output cavity;

[0047] During the process of the homogeneous melt flowing through the pressure equalization output chamber, the melt pressure is dynamically adjusted by the pressure setting parameters to obtain the initially regulated melt.

[0048] Real-time pressure equalization verification was performed on the initially regulated melt.

[0049] When the verification results meet the preset equilibrium criteria, the initially adjusted melt is determined to be a pressure-equilibrium melt.

[0050] Furthermore, by connecting multiple output channels to the pressure equalization output chamber, the pressure-equalizing melt is synchronously distributed to an odd number of hot nozzles of the mold, including:

[0051] Receive the pressure equalization melt and introduce it into the pressure equalization output chamber;

[0052] At the outlet of the pressure equalization output chamber, the pressure equalization melt is simultaneously received through multiple equally spaced output channels.

[0053] Real-time monitoring of melt pressure and flow rate in each output channel to ensure that they meet the synchronous distribution conditions;

[0054] When the synchronous distribution conditions are met, the pressure-equalizing melt is synchronously injected into the odd number of hot nozzles of the mold through each output channel;

[0055] During the injection molding process, the pressure consistency at each hot runner inlet is continuously verified to ensure that the pressure balance is maintained until filling is complete.

[0056] Secondly, the injection mold hot runner control system based on multi-hole flow distribution pressure equalization includes:

[0057] The initial collection module is used to inject molten plastic into the primary distribution chamber to form a collected melt; the collected melt is then passed through a multi-component flow orifice located between the primary distribution chamber and the secondary equalization chamber, thereby transforming the collected melt into a multi-stream flow melt.

[0058] The mixing and remelting module is used to introduce multiple streams of melt into a secondary equalization chamber, where the multiple streams of melt are mixed and remelted to form a homogeneous melt.

[0059] The deployment and acquisition module is used to arrange multiple dynamic pressure acquisition points at specific geometric locations in the secondary equalization cavity based on the formation of a homogeneous melt. The specific geometric locations include at least the center point of the inner wall near the gate, the center point of the inner wall far from the gate, and two side wall monitoring points symmetrically distributed along the radial direction, and to simultaneously acquire real-time pressure data from each dynamic pressure acquisition point.

[0060] The construction and calculation module is used to construct a three-dimensional pressure field isosurface volume characterizing the transient pressure distribution in the secondary equilibrium cavity based on real-time pressure data; calculate the volume change rate of the three-dimensional pressure field isosurface volume; and generate an adaptive pressure adjustment coefficient based on the volume change rate.

[0061] The pressure setting module is used to guide the homogeneous melt to the pressure equalization output chamber, and perform adjustable pressure setting on the homogeneous melt in the pressure equalization output chamber based on the adaptive pressure adjustment coefficient, thereby obtaining a pressure-equalized melt.

[0062] The synchronous distribution module is used to synchronously distribute the pressure-equalizing melt to an odd number of hot nozzles of the mold through multiple output channels connected to the pressure equalization output chamber.

[0063] The above-described solution of the present invention has at least the following beneficial effects:

[0064] Because it employs a multi-hole flow divider and multi-stage cavities (primary distribution cavity, secondary equalization cavity, and pressure equalization output cavity) working in tandem, along with multi-point pressure acquisition, three-dimensional pressure field analysis, and adaptive pressure adjustment technologies, it overcomes the limitations of traditional binary flow dividers in meeting the pressure equalization distribution requirements of odd-numbered hot nozzles. This also addresses the resulting technical problems of mold core misalignment, mold filling failure, and frequent mold trials. Consequently, it achieves precise equalization of the ejection pressure of odd-numbered hot nozzles, avoids molding defects such as short shots, reduces the number of mold trials and modifications, lowers production costs, and simultaneously improves mold delivery efficiency and product molding quality. Attached Figure Description

[0065] Figure 1 This is a schematic flowchart of an injection mold hot runner control method based on multi-hole flow pressure equalization provided by an embodiment of the present invention.

[0066] Figure 2 This is a schematic diagram of a hot runner control system for injection molds based on multi-hole flow distribution pressure equalization, provided by an embodiment of the present invention. Detailed Implementation

[0067] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0068] like Figure 1 As shown, embodiments of the present invention propose a hot runner control method for injection molds based on multi-hole flow distribution pressure equalization, the method comprising the following steps:

[0069] Step 1: Inject molten plastic into the primary distribution chamber to form a collected melt; allow the collected melt to pass through the multi-component flow orifice located between the primary distribution chamber and the secondary equalization chamber, thereby transforming the collected melt into a multi-stream flow melt;

[0070] Step 2: The multi-stream melt is introduced into the secondary equalization chamber. In the secondary equalization chamber, the multi-stream melt is mixed and remelted to form a homogeneous melt.

[0071] Step 3: Based on the formation of a homogeneous melt, multiple dynamic pressure acquisition points are arranged at specific geometric locations in the secondary equalization cavity. The specific geometric locations include at least the center point of the inner wall near the gate, the center point of the inner wall far from the gate, and two side wall monitoring points symmetrically distributed along the radial direction. Real-time pressure data of each dynamic pressure acquisition point are collected simultaneously.

[0072] Step 4: Based on real-time pressure data, construct a three-dimensional pressure field isosurface volume characterizing the transient pressure distribution within the secondary equilibrium cavity;

[0073] Step 5: Calculate the volume change rate of the three-dimensional pressure field isosurface and generate an adaptive pressure adjustment coefficient based on the volume change rate.

[0074] Step 6: The homogeneous melt is led to the pressure equalization output chamber, and an adjustable pressure setting is performed on the homogeneous melt in the pressure equalization output chamber based on the adaptive pressure adjustment coefficient, thereby obtaining a pressure-equalized melt.

[0075] Step 7: By connecting multiple output channels of the pressure equalization output chamber, the pressure equalization melt is synchronously distributed to an odd number of hot nozzles of the mold.

[0076] In this embodiment of the invention, through multi-stage processing of primary distribution cavity confluence, multi-component flow orifice diversion, and secondary equalization cavity mixing and remelting, combined with dynamic pressure acquisition at specific points, three-dimensional pressure field analysis and adaptive pressure adjustment, and after being calibrated by the pressure equalization output cavity, the pressure is synchronously distributed to the odd number of hot nozzles in the mold through multiple output channels. This achieves precise equalization of the discharge pressure of the odd number of hot nozzles, avoiding mold core misalignment and product molding defects. It also eliminates the need for repeated adjustment of the flow channel size, reduces the number of trial moldings, shortens the delivery cycle, and improves injection molding efficiency and product molding quality, providing reliable support for injection molding scenarios with multiple chambers and odd number of injection points.

[0077] In a preferred embodiment of the present invention, step 1 above may include:

[0078] Step 1.1: Molten plastic from the injection molding machine nozzle is introduced into the primary distribution chamber via the main flow path, allowing the molten plastic to form an initial aggregated melt within the primary distribution chamber. Specifically, the main flow path is made of a material resistant to high-temperature erosion by the molten plastic and with a low coefficient of friction. Both ends are tightly connected to the injection molding machine nozzle and the primary distribution chamber inlet via embedded sealing structures, preventing melt leakage and reducing temperature loss and flow resistance during transport. The primary distribution chamber is specially designed as a composite structure with a wider top and narrower bottom, and a sloping bottom. The slope is inclined towards the subsequent partition structure (with multi-component flow holes), and the inner wall of the chamber is mirror-polished to eliminate dead zones where the melt can stagnate. To meet the total supply requirements of the seven hot nozzles in the 12V lead-acid battery box, the injection molding machine precisely matches the melt output, ensuring the molten plastic is smoothly transported along the main flow path. After being fed into the primary distribution chamber, the melt naturally converges along the inclined slope under the guidance of the chamber structure. The chamber volume is strictly designed according to the total melt demand of a single injection from 7 hot nozzles, while reserving a buffer space of 10% to 15% to avoid squeezing turbulence when the melt fills the chamber. The feeding speed is dynamically adjusted according to the real-time filling progress of the chamber: a low-speed feeding is used in the initial stage to avoid the melt impacting the chamber wall and causing turbulence. When the melt fills to 1 / 3 of the chamber volume, it switches to uniform feeding to ensure that the melt spreads smoothly along the slope. When it fills to 2 / 3, it is finely slowed down again to form a gentle liquid surface layer at the top of the melt. Through this segmented speed adjustment + volume adaptation synergistic method, turbulence or local accumulation of the melt is avoided, and finally, an initial converged melt with uniform flow and a total amount accurately adapted to the subsequent diversion requirements is formed.

[0079] Step 1.2: Real-time monitoring of the cavity pressure within the primary distribution chamber, comparing the cavity pressure with a preset inlet pressure threshold to obtain the comparison result. Specifically, this includes: embedding a high-response pressure acquisition element in the middle region of the inclined slope at the bottom of the primary distribution chamber, ensuring the sensing end face of the element is flush with the inner wall of the cavity. This avoids interfering with melt flow while accurately capturing the overall melt pressure, avoiding direct impact from the feed inlet and preventing misjudgments caused by local pressure fluctuations. The preset inlet pressure threshold is not a fixed value, but rather a combination of the single-flow requirements of the seven hot nozzles, the pressure safety limit of the thin, high-mold core (to avoid lateral pressure overload leading to displacement), the viscosity, pressure, and temperature correlation characteristics of the plastic used, and the throttling resistance parameters of the subsequent multi-component flow orifices. This is achieved through multiple sets of simulated injection molding tests at different temperatures and feed rates. The dynamic adaptation range is obtained by collecting massive pressure data and performing curve fitting and range optimization. The upper threshold limit is used to limit the maximum pressure of the cavity, the lower threshold limit ensures the basic pressure required for subsequent diversion, and the middle range is the optimal pressure zone. The high-response pressure acquisition element continuously captures the melt pressure signal in the cavity at a frequency of once every 0.05 seconds, converts it into a continuous electrical signal and transmits it to the processing end. The processing end adopts a triple judgment method of real-time value comparison + moving average comparison + fluctuation amplitude verification: first, the single real-time pressure value is compared with the threshold range, then the instantaneous interference is weakened by 5 moving averages, and at the same time, the pressure fluctuation amplitude per unit time is monitored to see if it exceeds the allowable range of ±3%. Finally, a complete comparison result is formed, including whether the pressure value is within the threshold, whether the pressure is stable, and whether flow regulation needs to be initiated.

[0080] Step 1.3: Based on the comparison results, dynamically adjust the melt flow rate of the main flow path to stabilize the initial collected melt within a preset pressure range, forming a pressure-stable collected melt. Specifically, this includes: the flow regulation structure in the middle section of the main flow path adopts a gradual adjustment method adapted to the melt flow characteristics; the adjustment action is synchronized with the pressure acquisition frequency, responding once every 0.05 seconds to ensure timely adjustment; considering that the viscosity of the molten plastic will fluctuate slightly with temperature, the adjustment logic incorporates pressure change trend prediction: when the pressure shows a continuous upward or downward trend, the adjustment direction is predicted in advance to avoid lag causing pressure overshoot. The threshold is set; during the adjustment process, the change in the flow cross section is dynamically calculated by multiplying the pressure deviation value by the viscosity correction coefficient. The viscosity correction coefficient is preset according to the inherent characteristics of the plastic material to ensure consistent adjustment accuracy under different viscosity conditions; after each adjustment, the pressure response of the primary distribution chamber is continuously monitored. If the pressure fluctuation still exceeds the allowable range of ±3%, a slight secondary correction is performed. Through the closed-loop adjustment logic of prediction + real-time feedback + secondary fine adjustment, the pressure of the collected melt is stabilized within the optimal pressure band that adapts to the flow of 7 hot nozzles, ultimately forming a collected melt with minimal pressure fluctuation and stable state, providing a reliable premise for subsequent uniform flow distribution.

[0081] Step 1.4: Drive the pressure-stable collected melt through a multi-component flow orifice. The multi-component flow orifice is asymmetrically but with balanced flow rate, penetrating the partition between the primary distribution chamber and the secondary equalization chamber. Specifically, the partition structure between the primary distribution chamber and the secondary equalization chamber, in addition to possessing high strength and high-temperature resistance, also includes an auxiliary temperature control layer. By maintaining the temperature of the partition structure consistent with the melt temperature, it avoids sudden changes in melt viscosity due to temperature differences, thus preventing impact on the flow rate stability of the orifice. Referring to the core principle of uniform flow distribution in a showerhead, and considering the spatial distribution of the 7 hot nozzles in the 12V battery box, the orifice arrangement deliberately avoids the projection interference area of ​​the output flow channel corresponding to the hot nozzles, employing an asymmetrical arrangement of 9 orifices, more than the number of hot nozzles. Among these, 7 orifices... The projection direction is precisely aligned with the feeding path of the subsequent 7 hot nozzles. The remaining 2 holes serve as equalization redundancy holes. The aspect ratio of each flow hole is designed according to the principle of viscosity adaptation and throttling and pressure stabilization. Low-viscosity plastics correspond to a slightly larger aspect ratio, while high-viscosity plastics correspond to a slightly smaller aspect ratio. The effective flow area deviation of all flow holes is controlled within ±2%. The rounded transition radius of the inlet and outlet ends of the flow holes is optimized according to the melt flow trajectory to eliminate the risk of orifice eddies and shear degradation. The connection surface between the partition structure and the two-stage cavity adopts a planar bonding + high-temperature sealant-assisted sealing method, without any steps or gaps, to ensure that the stable collection of melt, driven by pressure, flows directionally and smoothly along each flow hole to the secondary equalization cavity. Moreover, the flow distribution ratio of each flow hole is precisely matched with the needs of the 7 hot nozzles.

[0082] Step 1.5: Through the throttling and guiding effect of the multi-component flow orifices, the pressure-stable aggregated melt is uniformly divided into multiple streams of melt with similar flow velocities and pressures. Specifically, the inclination angle of the multi-component flow orifices is uniformly designed to be between 15 and 20 degrees, and the outlet end of all orifices points to the central mixing area of ​​the secondary equalization chamber, ensuring that the multiple streams of melt can naturally converge after entering the secondary equalization chamber, creating conditions for mixing and remelting; the throttling effect of the flow orifices is achieved by precisely controlling the orifice diameter and length-to-diameter ratio, ensuring that the flow rate of a single melt stream meets the single-stream supply requirements of 7 hot nozzles, while avoiding pressure imbalance caused by excessive or insufficient flow; the guiding effect is achieved by guiding the flow of each stream of melt along a preset trajectory through the inclination angle, with adjacent flow orifices... The outlet spacing is designed to avoid melt collision interference, ensuring the stability of the melt state during the splitting process. When the stable and collected melt flows through the flow orifice, the throttling and guiding effects work together to evenly divide the continuous melt into 9 independent split melts. Among them, 7 streams are directly adapted to the subsequent hot nozzle feeding path, and the 2 redundant streams of split melt naturally merge with other melts after entering the secondary equalization chamber, further compensating for any possible flow rate differences. Through precise optimization of the flow orifice structure, the flow rate difference of each split melt is controlled within ±3%, the pressure deviation does not exceed ±2%, and the temperature and viscosity of the melt remain consistent, laying a solid foundation for the subsequent mixing and remelting process in the secondary equalization chamber, and ultimately ensuring the uniform dispensing pressure of the 7 hot nozzles.

[0083] In a preferred embodiment of the present invention, step 2 above may include:

[0084] Step 2.1 involves guiding multiple streams of melt with similar flow velocities and pressures from the multi-component flow orifice into the inlet area of ​​the secondary equalization chamber along a preset inlet angle. Specifically, this includes nine streams of melt from the multi-component flow orifice: seven core melt streams corresponding to the feeding needs of seven hot nozzles, and two redundant melt streams for equalization compensation. The guide strictly adheres to the preset 18-degree tilt guide angle of the flow orifice, which is precisely calibrated using locating pins during mold processing to ensure a fixed angle with the subsequent hot nozzle feeding path. A 3mm radius transition fillet is provided on the inner wall of the channel between the flow orifice outlet and the inlet area of ​​the secondary equalization chamber to prevent condensation during melt flow. Adhesion or eddies are generated; the inlet area adopts a trumpet-shaped gradually expanding structure, with the expanding angle consistent with the inclination angle of the flow orifice. The inner wall of the channel is mirror polished to Ra≤0.8μm to minimize flow resistance; the flow trajectory of the 9 melts is positioned and machined by the reference surface of the mold cavity. The core melt trajectory is precisely aligned with the feeding channels of the 7 hot nozzles, and the redundant melt trajectory fills the gap between the core melts, ensuring that all melts can smoothly advance along the preset trajectory after entering the inlet area. The flow rate deviation of each melt is controlled within ±3% and the pressure deviation does not exceed ±2%, laying a stable foundation for subsequent mixing.

[0085] Step 2.2: Within the inlet area, a flow guiding structure is used to facilitate the initial convergence and momentum exchange of the multi-streamed melts, thereby forming the initial converged melt. Specifically, this includes: uniformly arranging four streamlined arc-shaped flow guiding ribs along the melt flow direction on the inner wall of the inlet area of ​​the secondary equalization chamber. The cross-section of the flow guiding ribs adopts a teardrop shape, thinner at the top and thicker at the bottom, to avoid generating additional resistance to the melt flow; the spacing of the flow guiding ribs is precisely set according to the cross-sectional diameter of a single melt stream, with the spacing between adjacent ribs equal to 1.2 times the cross-sectional diameter of the melt, ensuring that each melt stream is gently guided by the flow guiding ribs; multi-streamed melts... Under the action of the guide ribs, the melt forms a spiral converging trajectory, rather than a simple straight-line convergence: the edges of adjacent melts first slowly contact each other at a 30-degree angle, and achieve initial momentum exchange through slight complementarity of flow velocities (the edge of the melt with a slightly faster flow velocity drives the edge of the melt with a slightly slower flow velocity), and then gradually converge towards the center of the inlet area; throughout the converging process, the guide ribs guide the melt to form a slight rotation, allowing the contact area of ​​the melt to gradually expand from the edge to the center, eliminating the slight pressure or flow velocity differences that may exist in a single melt stream, and finally forming an initial converging melt with preliminary fusion of components and a stable flow state.

[0086] Step 2.3: The initial confluence of melts is driven into the main mixing zone of the secondary equalization cavity. Within this zone, the turbulence generated by the cavity's geometry promotes thorough shear mixing and heat exchange between the multiple melt streams. Specifically, the initial confluence of melts flows smoothly into the main mixing zone of the secondary equalization cavity under the thrust of the confluence at the inlet region. The cavity cross-section of the main mixing zone is enlarged by a 1.8-fold ratio, and the inner wall is decorated with eight hemispherical turbulence protrusions arranged in an equilateral triangle. The diameter of each protrusion is 1 / 4 of the cavity radius, and the spacing between adjacent protrusions is twice the diameter of the protrusion, ensuring no dead zones in the flow field. When the melt flows... Upon passing the turbulence protrusion, the melt is divided into multiple secondary flows. Simultaneously, due to the expansion of the cross-section, the flow velocity slows down to 60% of the original velocity, forming a stable turbulent state. The melt advances along a Z-shaped flow path within the mixing zone, repeatedly turning around the turbulence protrusion, increasing the shear contact time between the melts. An electrically heated constant-temperature insulation layer is added to the cavity wall of the main mixing zone. The temperature sensor provides real-time feedback and maintains the cavity temperature consistent with the melt temperature, with a deviation of ≤±1℃, providing a stable environment for heat exchange. During this process, the melts of different streams intertwine and shear each other, and the temperature and viscosity differences gradually decrease, achieving sufficient shear mixing and heat exchange.

[0087] Step 2.4: Real-time monitoring of melt temperature and viscosity within the main mixing zone to ensure it remains within the preset remelting process window. This includes: two sets of temperature sensing elements and two sets of viscosity sensing elements are embedded diagonally and symmetrically in the middle and near-end positions of the main mixing zone. The sensing ends of the elements are flush with the inner wall of the cavity. High-temperature resistant ceramic gaskets are used for sealing during installation to prevent melt leakage. The temperature sensing elements have a measurement range covering the plastic melting point from +10℃ to +30℃, with an accuracy of ±0.5℃. The viscosity sensing elements indirectly obtain viscosity values ​​by monitoring melt flow resistance, with a measurement accuracy of ±50 mPa·s. The preset remelting process window is calibrated through multiple batch tests: three different batches of target plastics PP or ABS are selected and tested at different temperatures (melting point +15℃ to +25℃) and viscosities (1500 mPa·s to 2500 mPa·s). Mixing experiments were conducted under various conditions to record the homogeneity data of the melt and ultimately determine the optimal range. During monitoring, a three-point averaging method was used to process the data. Specifically, two diagonal elements in the middle of the main mixing zone and one key element near the end were used as three fixed monitoring points, and raw temperature and viscosity data were collected simultaneously at the same time. The arithmetic mean of the three sets of data was used to offset the error caused by instantaneous fluctuations at single points, making the monitoring results more consistent with the actual state of the melt. This method does not require complex calculations, can quickly smooth high-frequency noise, and at the same time retain the core change trend of the melt state, reducing instantaneous fluctuation errors. An ambient temperature compensation coefficient was also added. When the ambient temperature changes by more than ±3℃, the monitoring results are automatically corrected. If the data exceeds the process window, the temperature is finely adjusted by the electric heating wire of the constant temperature insulation layer, with each adjustment being ±1℃, indirectly correcting the viscosity to ensure that the melt is always in a suitable remelting state.

[0088] Step 2.5: Under the condition of meeting the remelting process window, the fully mixed melt undergoes final thermal homogenization and molecular chain reconstruction at the end of the main mixing zone to form a homogeneous melt with uniform physical properties. Specifically, this includes: the end of the main mixing zone adopts a 30-degree tapered structure, which is precision-machined to ensure a uniform tapering angle, guiding the melt to gradually converge without causing sudden pressure changes; the temperature of the constant temperature insulation layer in the end region is controlled with an accuracy of ±0.3℃, maintaining complete consistency with the temperature of the main mixing zone; the flow velocity of the melt in the end region is controlled at 5 to 8 mm / s, and the length of the tapered structure is adjusted to 50 mm for thermal homogenization. Sufficient time is allowed for homogenization: heat inside the melt is uniformly transferred through molecular thermal motion, eliminating residual local temperature differences; at the same time, the tapered structure forms a stable pressure field of 0.6 to 0.8 MPa. Under this pressure, the melt molecular chains fully extend, breaking the original local aggregation state and reforming into a regular and uniform molecular arrangement; during this process, the two redundant melt streams completely penetrate into the seven core melt streams through pressure extrusion, eliminating all stream boundaries, and finally forming a homogeneous melt with highly uniform temperature, viscosity, and density and no difference in physical properties, providing an ideal melt foundation for the dynamic pressure monitoring and precise adjustment of the subsequent secondary equalization chamber.

[0089] In a preferred embodiment of the present invention, step 3 above may include:

[0090] Step 3.1: On the inner wall of the secondary equalization chamber, select a set of key sampling points to characterize the dynamic pressure distribution. These key sampling points include at least a proximal sampling point near the center of the inner wall on the side closest to the shunt inlet, a distal sampling point away from the center of the inner wall on the side furthest from the shunt inlet, and a pair of lateral sampling points located on both sides of the chamber and symmetrically distributed relative to the central axis of the chamber. Specifically, considering the axial flow path and radial symmetry of the secondary equalization chamber, as well as the thin and high core characteristics of the 12V lead-acid battery casing and its sensitivity to lateral pressure, and adhering to the requirement of balanced feeding from seven hot nozzles, precisely select key sampling points covering axial pressure changes and radial pressure equalization. The proximal sampling point is located near the shunt inlet. The center of the initial flow section on the inlet side is aligned with the convergence area of ​​the nine melt streams (seven core streams + two redundant streams) just entering the cavity. This is used to capture the pressure baseline value before sufficient mixing, providing a reference for subsequent pressure change analysis. The distal point is located at the end of the main mixing zone, adjacent to the inlet of the pressure equalization output cavity. It directly corresponds to the pressure state of the seven hot nozzles before feeding, monitoring the final pressure stability of the melt after mixing and remelting. On both sides of the cavity wall, a pair of lateral points are selected that are strictly symmetrical with the central axis of the cavity. The projection direction of these two points exactly covers both sides of the feeding path of the seven hot nozzles, accurately corresponding to the key stress area of ​​the mold core's lateral pressure. This is specifically used to monitor whether the radial pressure is balanced, avoiding mold core displacement due to excessive pressure on one side.

[0091] The determination of all key points is based on multi-dimensional mold flow analysis, and the specific implementation process is as follows: First, the three-dimensional solid configuration of the secondary equalization chamber, the precise position coordinates of the seven hot nozzles, and the dimensions of the feeding channel are imported. At the same time, the viscosity, temperature, and pressure correlation curves of the target plastic PP or ABS, the temperature set for the injection molding process (melting point +15℃ to +25℃), and the melt flow rate of 5 to 8 mm / s are input to construct a simulation environment consistent with the actual injection molding scenario. Second, the complete flow process of the melt from the diversion hole into the secondary equalization chamber, through convergence, mixing and remelting, to flow to the seven hot nozzles is simulated. The key outputs are the velocity vector distribution map, the pressure gradient distribution map, and the melt residence time distribution map. Based on the velocity vector map, the turbulent melt flow direction, the vortex region with a flow rate below 0.5 mm / s, and the stagnation dead zone with a residence time exceeding 1.5 times the overall flow cycle are identified. All key points avoid these areas to ensure that the collected pressure data is not affected by invalid flow states.

[0092] Simultaneously, the correlation mapping between the pressure at different points within the cavity and the feeding pressure of the seven hot nozzles was analyzed and established: using the inlets of the seven hot nozzles as the simulation output boundary, the correlation between the pressure changes at different points within the cavity and the corresponding feeding pressure of the hot nozzles was monitored: the deviation between the pressure at the proximal point and the initial feeding pressure of the seven hot nozzles was controlled within ±2%, directly reflecting the pressure balance of the initial distribution of the nine melt streams; the correlation between the pressure at the distal point and the actual dispensing pressure of the seven hot nozzles reached over 95%, accurately capturing the final feeding pressure state after mixing and remelting; the pressure at the lateral points was directly linked to the forces on both sides of the mold core, and the pressure difference directly affected the lateral pressure balance during hot nozzle feeding. By analyzing the correspondence between lateral pressure and mold core offset, it is ensured that the position can accurately capture the minute pressure differences that cause mold core offset. Finally, through more than three rounds of mold flow analysis and iterative optimization: first, the position is initially selected, and its pressure data correlation and effectiveness are verified by simulation. Then, the spatial coordinates of the position are finely adjusted according to the simulation results, with a deviation of no more than 0.5mm, until the pressure data of all positions can comprehensively and accurately reflect the pressure attenuation and stabilization trend of the axial inlet, mixing and outlet of the cavity, as well as the pressure balance state of the radial center and both sides. Moreover, the data of each position can directly provide targeted monitoring basis for the pressure balance adjustment of the seven hot nozzles.

[0093] Step 3.2: Install high-response miniature pressure sensors at each key acquisition point to construct a multi-point pressure sensing array that matches the cavity structure. Specifically, this includes fixing the high-response miniature pressure sensor at each key acquisition point using an embedded groove + flush-mount mounting method. The sensor's sensing end face is precisely ground to be absolutely flush with the inner wall of the cavity. High-temperature resistant sealing material is filled between the groove and the sensor, and the outer layer is then pressed and sealed with a pressure ring, forming a double-sealed structure to prevent melt leakage under high temperature and pressure, while also preventing the sensor from protruding from the cavity wall and interfering with the homogeneous melt flow. The selected sensor must be compatible with the high-temperature environment of the melt (matching PP or ABS plastic melting). The system measures temperature and dynamic pressure changes with a response time of no less than 0.05 seconds. The measurement range covers the extreme range of pressure fluctuations within the secondary equalization chamber, ensuring the capture of minute pressure changes affecting the balanced feeding of the seven hot nozzles. After installation, all sensors undergo unified calibration: different pressure gradients are applied using a standard pressure source, and the correspondence between the sensor output signal and the actual pressure is recorded to correct individual differences and ensure consistent measurement accuracy across all sensors. Furthermore, a multi-point pressure sensing array is constructed using shielded differential transmission lines to precisely match the structure of the secondary equalization chamber and the feeding logic of the seven hot nozzles, reducing electromagnetic interference in high-temperature environments and ensuring the stability and synchronization of signal transmission.

[0094] Step 3.3: When the homogeneous melt flows through the secondary equalization chamber, the multi-point pressure sensor array is activated synchronously. Specifically, this includes establishing a dual-linkage triggering mechanism based on the melt state monitoring signal and the melt convergence state: when the melt temperature and viscosity are consistently within the remelting process window for three consecutive acquisition cycles as monitored in step 2.4, and the melt has flowed to the middle section of the main mixing zone and is about to enter the final convergence stage in step 2.5, the synchronous activation procedure of the multi-point pressure sensor array is triggered; before activation, the sensor is preheated and adapted to adjust its operating temperature to be close to the ambient temperature of the chamber. To avoid initial measurement errors caused by temperature shocks, the activation process uses a unified high-precision clock reference signal as an instruction to ensure that all sensors in the array enter the working state at the same time, with time deviation controlled at the microsecond level, eliminating the spatiotemporal misalignment of pressure data caused by activation time difference; the activation timing is precisely focused on the stable flow stage of the melt in the secondary equalization chamber, neither prematurely activating to collect invalid initial fluctuation data, nor delaying activation to miss key pressure stable states, ensuring that the sensors can completely capture the entire process of pressure dynamic changes of the homogeneous melt from the completion of mixing to before flowing to the 7 hot nozzles.

[0095] Step 3.4 involves using a multi-point pressure sensor array to collect instantaneous melt pressure signals at key sampling points in real time and synchronously. Specifically, the sampling frequency of the multi-point pressure sensor array is optimized through mold flow analysis. Considering the melt flow velocity of 5 to 8 mm / s within the cavity and the pressure response requirements of the seven hot nozzles, a sampling frequency of once every 0.05 seconds is set. This ensures accurate capture of minute pressure fluctuations affecting mold core stability (within ±2%) without generating redundant data. During the sampling process, all sensors operate synchronously with a unified clock reference, directly sensing the actual instantaneous pressure of the melt in contact with the cavity wall. High-frequency noise generated by melt turbulence is eliminated by built-in low-pass filtering logic, without affecting the effective pressure signal and ensuring the authenticity of the original signal. Shielded differential cables are used for signal transmission to avoid electromagnetic interference and signal attenuation in high-temperature environments, converting the physical quantity of pressure into a standardized electrical signal for real-time transmission to the processing end. Simultaneously, the signal collected by each sensor is bound to the corresponding key location markers (near end, far end, left side, right side) to ensure that pressure data from different locations at the same time can be accurately correlated, forming a preliminary correlation between time, location, and pressure, providing reliable raw data support for the subsequent construction of a three-dimensional pressure field.

[0096] Step 3.5 involves synchronizing the collected instantaneous pressure signals from various points to generate a set of original dynamic pressure datasets for the cavity with spatiotemporal correlation. Specifically, this includes: First, precise time calibration: using the sensor signal at the near-end point as a reference, combined with the flow time of the melt from the near end to the far end and lateral points, and calculating based on the melt flow velocity and the distance between points, delay compensation is applied to the pressure signals at the far end and lateral points to eliminate the time difference caused by melt flow, and all signals are precisely aligned along a unified time axis. Then, spatial correlation and binding are performed: each pressure signal is labeled with its corresponding three-dimensional spatial coordinates, based on the precise installation position of the point, and associated with the corresponding hot nozzle feeding area: the near-end signal is associated with the initial pressure distribution of the nine melt streams, and the far-end signal is... The feed pressure benchmarks of seven hot nozzles are linked. The left-side location signal is associated with the lateral pressure of hot nozzles 1 to 3, and the right-side location signal is associated with the lateral pressure of hot nozzles 5 to 7, forming a four-dimensional associated data set of timestamp, spatial coordinates, pressure value, and feeding area. Then, through outlier processing logic: a reasonable threshold is set based on the pressure adaptation range of the seven hot nozzles. Signals exceeding the threshold are marked as outliers but the original data is retained, which facilitates subsequent tracing of the cause of pressure imbalance. At the same time, the signal is smoothed by the sliding window averaging method to reduce instantaneous interference. Finally, a complete set of original dynamic pressure datasets of the cavity is generated, which retains the pressure changes in the secondary equalization cavity over time and space and is directly associated with the feeding status of the seven hot nozzles. This provides targeted data support for subsequent construction of a three-dimensional pressure field and precise pressure adjustment.

[0097] In a preferred embodiment of the present invention, step 4 above may include:

[0098] Step 4.1: Obtain the raw dataset of dynamic pressure in the cavity. This includes obtaining the generated complete raw dataset of dynamic pressure in the cavity. This dataset has a four-dimensional relational structure and contains four core parameters: timestamp t, spatial coordinates (x, y, z), instantaneous pressure value P, and feeding area identifier K. The timestamp t is recorded with a unified clock reference in seconds. The spatial coordinates (x, y, z) accurately correspond to the inner wall of the secondary equalization cavity and the actual physical location of the cavity, and are bound to the feeding paths of the seven hot nozzles. The instantaneous pressure value P is the measured pressure at each key point in megapascals (MPa). The feeding area identifier K directly corresponds to the dedicated feeding area of ​​hot nozzles 1 to 7. For example, K=1 corresponds to the feeding area of ​​hot nozzle 1. This dataset has been time-calibrated, spatially bound, and marked with outliers. It has removed obviously distorted invalid data and fully preserved the dynamic characteristics of pressure changes over time and space. Each data point can be traced back to the feeding pressure state of the corresponding hot nozzle, providing a direct and reliable data source for the subsequent construction of the three-dimensional pressure field.

[0099] Step 4.2: Using the spatial coordinates of key acquisition points as a reference, perform spatial interpolation calculations on the instantaneous pressure signals in the original dynamic pressure dataset of the cavity to generate a spatial pressure distribution function covering the entire inner cavity of the secondary equalization cavity. Specifically, this includes: to achieve comprehensive coverage of the pressure inside the secondary equalization cavity, using the four determined key acquisition points as known references, the inverse distance weighted IDW interpolation method is used to expand the pressure data. This method can conform to the transmission law of melt pressure having a large influence near the point and a small influence far from the point, accurately matching the pressure distribution characteristics of the seven hot nozzle feeding areas. The specific implementation process is as follows: first, determine the core information of the four reference points: mark the near end, far end, left side, and right side points as i=1, 2, 3, and 4 respectively, and record their precise spatial coordinates (x, y, y). i y i , z i ) and the corresponding measured instantaneous pressure value P i The data is taken from the original dataset; then the Euclidean distance between the interpolation point and the reference point is calculated: the inner cavity of the secondary equalization cavity is divided into a three-dimensional mesh with uniform intervals of 1 mm, and each mesh node is an interpolation point (x, y, z), using the formula:

[0100] ;

[0101] Calculate the straight-line distance d between this point and the four reference points. i Unit: mm, ensuring the distance calculation accurately reflects the physical spatial relationship; then substitute into the interpolation formula to calculate the pressure value: Interpolation formula used:

[0102] ;

[0103] The weighting coefficient p is set to 2. After multiple sets of experiments, this value can optimally balance the influence weight of the reference point on the interpolation point, which is in line with the law of melt pressure transmission. The pressure calculation value P(x, y, z) of each interpolation point is calculated one by one. A spatial pressure distribution function is generated: the (x, y, z) coordinates of all interpolation points are integrated with the corresponding P(x, y, z) values ​​to form a spatial pressure distribution function P(x, y, z) that continuously covers the entire inner cavity of the secondary equalization cavity. This function can not only reflect the pressure changes in the cavity axis (inlet, outlet) and radial direction (center, sides), but also accurately map the pressure status of the feeding areas of hot nozzles 1 to 7, providing complete pressure data support for subsequent three-dimensional reconstruction.

[0104] Step 4.3: Based on the spatial pressure distribution function, reconstruct the transient pressure field point cloud reflecting the pressure values ​​at various points within the cavity at the same moment in a three-dimensional coordinate system. Specifically, this includes: based on the physical structure of the secondary equalization cavity and the distribution characteristics of the seven hot nozzles, first establishing a dedicated three-dimensional coordinate system, and then generating the transient pressure field point cloud through data mapping to ensure that the pressure distribution accurately corresponds to the actual injection molding scenario. The specific implementation process is as follows:

[0105] First, establish a three-dimensional coordinate system: set the center of the near end point as the origin O(0, 0, 0), the X-axis extends along the cavity axis, from the inlet to the outlet, consistent with the melt flow direction; the Y-axis extends radially along the cavity, from the left end point to the right end point, corresponding to the lateral pressure direction of the mold core; the Z-axis is perpendicular to the XY plane, covering the upper and lower sections of the cavity, and the scale unit of the coordinate system is uniformly mm to ensure that the coordinate values ​​can directly correspond to the actual size of the cavity; then extract the interpolation point association information: based on the spatial pressure distribution function P(x, y, z), extract the three-dimensional coordinates (x, y, z) and pressure calculation value P(x, y, z) of each uniform grid interpolation point, and bind the corresponding hot nozzle feeding area identifier K according to the spatial position of the interpolation point, such as the interpolation point near the feeding path of hot nozzle No. 3, which is identified as K=3.

[0106] Finally, a transient pressure field point cloud is generated: all interpolation points are filtered according to a unified timestamp t, and the three-dimensional coordinates, pressure values, and material feeding area identification data groups at the same time are spatially mapped and located one by one in the established three-dimensional coordinate system; in order to accurately capture the pressure details of the hot nozzle feeding area, the grid spacing is increased to 0.5mm around the feeding path corresponding to the 7 hot nozzles, making the point cloud denser in key areas; the final transient pressure field point cloud completely covers the cavity inlet area, the main mixing area, and the end convergence area, clearly presents the pressure distribution of each location in the cavity at the same time, and can be directly associated with the feeding pressure status of each hot nozzle.

[0107] Step 4.4 involves extracting isosurfaces and fitting surfaces from the transient pressure field point cloud to construct a three-dimensional pressure field isosurface volume characterizing the transient pressure distribution during the current injection molding cycle. Specifically, this includes: transforming the discrete pressure point cloud into an intuitive three-dimensional pressure field isosurface volume through isosurface extraction and surface fitting, providing a visual and quantitative basis for the pressure equalization adjustment of the seven hot runners. The specific implementation process is as follows: first, set the pressure isosurface constant; then, considering the injection molding process requirements of the 12V lead-acid battery box, the pressure adaptation range of the seven hot runners (0.6 to 0.8 MPa), and the pressure bearing limit of the mold core, set... Three core pressure isostatic constants C are defined as C1 = 0.6 MPa (minimum adaptive pressure), C2 = 0.7 MPa (optimal equilibrium pressure), and C3 = 0.8 MPa (maximum safe pressure), covering the key range of pressure regulation. Next, discrete points on the isosurface are extracted. Based on the transient pressure field point cloud, discrete points corresponding to each pressure isostatic constant are selected, i.e., all interpolation points satisfying P(x, y, z) = C. These points constitute the discrete isosurface profile of the corresponding pressure value. Among them, the isosurface corresponding to C2 = 0.7 MPa directly reflects the optimal pressure equilibrium state and is the core reference for subsequent regulation.

[0108] Secondly, surface fitting optimization is performed: a multivariate quadratic polynomial least squares fitting method is used to smooth the discrete points of each pressure isostatic point. The fitting formula is as follows:

[0109] ;

[0110] In the formula, x, y, and z are the three-dimensional coordinates of any point on the fitted surface, in mm, and P(x, y, z) is the pressure value at that point, which is equal to the set constant C. to The fitting coefficients are calculated using the least squares method to minimize the sum of squared errors between the discrete points and the fitted surface, ensuring that the fitted surface accurately matches the distribution trend of the discrete points while eliminating the interference of small fluctuations in the point cloud. Finally, a three-dimensional pressure field isosurface is constructed: the fitted surfaces of the three pressure isosurfaces at the same moment are integrated to form a complete three-dimensional pressure field isosurface. This isosurface can intuitively show whether the pressure in the seven hot nozzle feeding areas is within the range of 0.6 to 0.8 MPa, whether the pressure in the Y-axis direction on both sides of the mold core is balanced, and whether the axial pressure decreases smoothly from the inlet to the outlet, providing clear quantitative and visual support for subsequent targeted pressure adjustment and prevention of mold core displacement.

[0111] In a preferred embodiment of the present invention, step 5 above may include:

[0112] Step 5.1: Obtain the three-dimensional pressure field isosurface volume at multiple consecutive moments within the current injection molding cycle. Specifically, this includes obtaining the three-dimensional pressure field isosurface volume at multiple consecutive moments within the current injection molding cycle, covering the entire process from the initial melt filling stage, the middle filling stage, the mixing and remelting stage, the pressure stabilization stage, and the pre-discharge preparation stage. This ensures complete capture of the dynamic evolution of the seven hot runner supply pressures from establishment to stabilization, accurately matching the characteristics of thin and high mold cores and lateral pressure sensitivity. The injection molding cycle duration is set according to the injection molding process of a 12V lead-acid battery box, typically 3 to 5 seconds. The interval between consecutive acquisitions is consistent with the pressure acquisition frequency in Step 3, with one moment every 0.05 seconds. A total of 60 to 100 consecutive moments of data are collected per injection molding cycle to avoid omissions. The key pressure change nodes are omitted; the three-dimensional pressure field isosurfaces at each moment are directly derived from the construction results in step 4.4. In addition to the core optimal pressure isosurface of 0.7MPa, the lateral pressure sensitive isosurfaces of 0.65MPa and 0.75MPa are also synchronously associated: these two isosurfaces correspond to the safe critical values ​​of the lateral pressure of the mold core, which are specifically used to monitor the lateral pressure dynamics of the feeding areas of the hot nozzles on the left and right sides; all isosurfaces are bound to the feeding area identifiers of hot nozzles 1 to 7 and the corresponding lateral position information, namely hot nozzles 1 to 3 on the left, hot nozzle 4 in the middle, and hot nozzles 5 to 7 on the right, to ensure that the pressure distribution data at each moment can be accurately traced to the specific hot nozzle and the stress area of ​​the mold core, providing a targeted data source for subsequent analysis.

[0113] Step 5.2: Calculate the instantaneous volume of the three-dimensional pressure field isosurface at each continuous moment, generating a set of volume values ​​arranged in a time sequence. Specifically, the core objective of calculating the instantaneous volume is to directly correlate the supply pressure state of the seven hot nozzles and the lateral force stability of the mold core by quantifying the spatial range of the pressure equilibrium region, fully adhering to the pressure balance logic of melt remelting after the showerhead splits. The specific implementation process is as follows: Lock the boundary of the calculation space. First, clarify the core range of the volume calculation, strictly limiting it to the connection area between the secondary equilibrium cavity and the pressure equalization output cavity: This area is the key pressure balance section after the melt is mixed and remelted and before it is distributed to the seven hot nozzles, which can most directly reflect the supply pressure distribution. The boundary division completely follows the physical structure of the cavity and the melt flow path, avoiding the cavity dead corners and non-flow areas that are not related to the hot nozzle supply channel, ensuring that the calculation object accurately corresponds to the effective space of actual pressure transmission.

[0114] Next, effective pressure regions are screened. Based on the constructed 3D pressure field isosurface, two core regions are selected: first, the region enclosed by the optimal pressure isosurface, which directly corresponds to the ideal pressure state of the seven hot nozzles, and its volume reflects the coverage of overall pressure balance; second, the lateral pressure sensitive region of the mold core. According to the force direction on both sides of the mold core, the pressure isosurface regions corresponding to the left and right hot nozzle groups are separated. The volume difference between these two types of regions will directly reflect whether the lateral pressure is unbalanced. During the screening process, only the pressure regions directly connected to the hot nozzle feeding channels are retained, and the ineffective pressure regions formed by melt eddies and local stagnation are eliminated to ensure that the volume data can truly reflect the pressure balance effect.

[0115] Then, a three-dimensional volume calculation is performed, using a three-dimensional spatial calculation method that fits the melt flow state. Based on the spatial coordinate boundary of the isosurface, the overall volume of the selected effective area is solved. The calculation is not limited to simple geometric volume calculation, but combines the flow inertia and pressure transmission characteristics of the melt to ensure that the calculation results can reflect the actual coverage of the pressure field, rather than simply the physical volume of the cavity. For example, for areas where the pressure does not reach the ideal value, even if they are within the physical flow channel, they are not included in the effective volume statistics to avoid interference from invalid data.

[0116] Finally, the data is integrated to form a time series: the calculation results at each moment are integrated into a three-dimensional data set consisting of the overall pressure equilibrium volume + the volume of the left lateral pressure region + the volume of the right lateral pressure region, and arranged in chronological order to form a complete time series; each data set is labeled with a corresponding timestamp and injection stage, such as the melt mixing and remelting period and the pressure stabilization period, and associated with specific hot nozzle group identifiers, such as the left hot nozzle, the middle hot nozzle, and the right hot nozzle. This not only quantifies the dynamic changes in the overall pressure equilibrium, but also monitors the pressure volume difference on both sides of the mold core in real time, providing a direct quantitative basis for subsequent analysis of the risk of lateral pressure imbalance.

[0117] Step 5.3: Based on the volume values ​​arranged in a time series, calculate the ratio of the change in volume values ​​at adjacent moments to the time interval, thereby obtaining a volume change rate sequence. Specifically, this includes: generating a volume change rate sequence reflecting the dynamic trend of the pressure field based on the time series volume group, using a logic of segmented calculation + difference filtering + physical meaning association; First, using a fixed time interval of 0.05 seconds as a benchmark, calculate the volume changes of three groups for volume data at two adjacent moments: core equilibrium volume change ΔVcore = volume at the next moment - volume at the previous moment); left lateral volume change ΔVleft; right lateral volume change ΔVright; Subsequently, calculate the ratio of each group of volume changes to the time interval to obtain three sets of volume change rates: core change rate rcore = ΔVcore / 0.05s, left change rate rleft = ΔVleft / 0.05s, and right change rate rright = ΔVright / 0.05s; During the calculation process, an effective change filtering mechanism is introduced: small fluctuations caused by slight equipment vibration or signal interference are eliminated, and the absolute value of the change rate is less than 0.01mm. 3 / s, only retaining the actual changes related to melt flow and pressure transmission; the three sets of change rates are integrated into a complete volume change rate sequence by time series, and each data point in the sequence is associated with the corresponding injection stage and hot runner pressure state: for example, in the initial filling stage, r_core is positive and has a large value, reflecting the rapid expansion of the core pressure equilibrium area, corresponding to the gradual establishment of the feeding pressure of the 7 hot runners; during the pressure stabilization period, r_core is close to 0, and the difference between r_left and r_right is less than 0.02-0.03mm. 3 / s reflects the overall pressure stability and the balanced lateral pressure of the mold core, preparing for the hot nozzle to dispense glue, and ensuring that the rate of change sequence can accurately map the core dynamics of the pressure field.

[0118] Step 5.4: Extract characteristic rates of change representing the dynamic evolution trend of the pressure field from the volume change rate sequence. Specifically, this includes extracting four types of characteristic rates of change directly related to the pressure balance of the seven hot nozzles and the lateral stability of the mold core, comprehensively capturing the core trend of the dynamic evolution of the pressure field. The first type is the core peak change rate r-core: the maximum absolute value of the core change rate r-core in the entire sequence is selected. This value corresponds to the fastest expansion / contraction rate in the mid-stage pressure equilibrium region, reflecting the efficiency of melt pressure transfer to the seven hot nozzles. If the r-core peak is too large, exceeding 0.5 mm... 3 / s indicates that excessively fast pressure transmission may lead to excessive pressure in some hot nozzles, while too small a value indicates insufficient transmission and may cause uneven glue dispensing; the second type is the stable period uniform change rate r_stable_average: select the core change rate data of the pressure stabilization period 0.5 seconds before glue dispensing, calculate its arithmetic mean. The closer this value is to 0, the more stable the material supply pressure of the 7 hot nozzles is, which is directly related to the uniformity of glue dispensing.

[0119] The third category is the lateral pressure difference change rate r_lateral_difference: Calculate the difference between the left-side change rate r_left and the right-side change rate r_right at each moment, where r_lateral_difference = |r_left - r_right|. Extract the maximum value of r_lateral_difference during the stable period. This value directly reflects the risk of lateral pressure imbalance in the mold core, exceeding 0.01mm. 3 / s requires targeted adjustment to avoid core displacement; the fourth category is the edge hot nozzle related change rate r edge: extract the change rate data of the material supply area corresponding to edge hot nozzles No. 1 and No. 7, calculate the difference between its change rate and the change rate of the middle No. 4 hot nozzle area, reflect the pressure transmission difference between the edge and the middle hot nozzle, and ensure that the edge hot nozzle does not have insufficient pressure due to its remote position; during the extraction process, by comparing with the change rate threshold of multiple combination injection molding cycles, abnormal and sudden data are eliminated to ensure that the characteristic change rate can truly reflect the core dynamics of the pressure field, and provide precise targeting for subsequent adjustment.

[0120] Step 5.5: Input the characteristic change rate into the preset adjustment coefficient mapping model. Through the nonlinear transformation of the preset adjustment coefficient mapping model, generate an adaptive pressure adjustment coefficient for adjusting the working state of the pressure equalization output cavity. Specifically, the preset adjustment coefficient mapping model is constructed around the nonlinear mapping requirements of industrial scenarios. It is based on the improved radial basis function neural network RBF-NN. This architecture is inherently adapted to nonlinear and multi-factor coupled industrial control scenarios. It has fast training speed and strong real-time responsiveness, which meets the core requirements of the present invention for rapid mold exchange and real-time pressure adjustment. At the same time, it deeply integrates the pressure equalization logic of the shower head diversion principle and is specially optimized for the feeding characteristics of the 7 hot nozzles and the problem of lateral pressure sensitivity of the mold core.

[0121] The model adopts the basic three-layer RBF-NN structure of input, hidden layer, and output layer, with key modules optimized for the needs of this invention. The input layer has 4 neurons, corresponding to the four types of feature change rates extracted in step 5.4: r-core peak, r-stable average, r-lateral difference, and r-edge relationship, which are directly related to the pressure transmission efficiency and core stability of the 7 hot nozzles. The hidden layer uses a Gaussian activation function because it can accurately fit the nonlinear relationship between melt pressure and adjustment coefficient, such as the nonlinearity of PP or ABS melt viscosity with temperature change and the coupling relationship of pressure rebalancing after the showerhead splits. The number of nodes in the hidden layer was determined to be 15 in the preliminary experiments to ensure that the mapping logic is covered under all working conditions. The output layer has 2 neurons, which output the flow channel cross-section fine-tuning coefficient k1 and the local temperature compensation coefficient k2, respectively. The value range of k1 is (0.95, 1.05) and the value range of k2 is (0.98, 1.02), corresponding to the two adjustment dimensions of the pressure equalization output cavity.

[0122] A simplified attention module is added between the input layer and the hidden layer to emphasize the influence of r_stability_average and r_lateral_difference features. The weight of r_stability_average is set to 0.4, and the weight of r_lateral_difference is set to 0.3. These two features directly determine the glue dispensing balance of the seven hot nozzles and the lateral stability of the mold core, which are the core problems to be solved by this invention. At the same time, the basic weights of r_core_peak and r_edge_affinity are weakened, with the weight of r_core_peak set to 0.2 and the weight of r_edge_affinity set to 0.1. Attention is increased only when they exceed the normal range, ensuring that the core contradiction is resolved first, while also taking into account the pressure balance and pressure transmission efficiency of the edge hot nozzles. A dynamic correction unit is embedded at the end of the output layer to pre-store the association rules between feature overshoot and weight tilt adjustment. For example, when r_lateral_difference exceeds 0.02 to 0.03 mm. 3 When / s, the adjustment weight of k2 in the corresponding side is automatically amplified by 1.5 times, and the pressure on both sides of the mold core is quickly balanced through temperature fine adjustment; when the r edge exceeds the standard, that is, when the difference between the edge and the middle hot nozzle change rate is too large, the output weight of k1 corresponding to hot nozzle No. 1 and No. 7 is increased in a targeted manner, and the pressure loss of the edge hot nozzle is compensated by expanding or shrinking the flow channel cross section, so as to ensure that the adjustment coefficient is accurately targeted to the problem.

[0123] The model training process revolves around actual injection molding scenarios. First, over 50 sets of injection molding test data for 12V lead-acid battery boxes covering different working conditions are collected. The working condition design fully matches actual production needs, including three commonly used PP / ABS grades to adapt to different viscosity characteristics, two battery box single-chamber sizes to correspond to different runner length requirements, five sets of different injection temperatures covering the material melting range, and three sets of different melt flow rates, ensuring the comprehensiveness and representativeness of the data. In each set of tests, real-time data of four characteristic change rates are recorded simultaneously, along with the optimal adjustment coefficient verified as product qualification through trial molding. The product qualification standard is no mold core offset and uniform glue discharge. For example, in one set of tests, the r-core peak was too high when using high-viscosity PP material. After three trial moldings, pressure balance was determined when k1=0.97 and k2=1.01. This set of data is used as the training sample.

[0124] The data preprocessing stage first removes outlier samples, such as pressure spikes caused by equipment hydraulic malfunctions and false sensor alarms, to ensure the training data is authentic and valid. Then, the feature rate of change and adjustment coefficient are normalized, mapping the feature rate of change to the (0, 1) interval, for example, r averaging ±0.01 to ±0.02 mm. 3 / s corresponds to 0.2 to 0.8. k1 (0.95, 1.05) and k2 (0.98, 1.02) are mapped to the (0, 1) interval respectively to avoid the impact of data magnitude differences on training performance. Finally, the data is divided into training and validation sets in an 8:2 ratio. The training set contains more than 40 sets of data for model parameter learning, while the validation set contains fewer than 10 sets of data for evaluating the model's generalization ability.

[0125] The model training aimed to achieve a pressure difference of ≤ ±0.02 MPa between the seven hot nozzles and ≤ ±0.01 MPa between the mold core lateral pressure difference. Training data was input into the model for parameter learning. The center value and width of the Gaussian function in the hidden layer were optimized using gradient descent, and the attention weights in the input layer were adjusted to gradually reduce the error between the model's output k1 and k2 and the actual optimal adjustment coefficients. Five-fold cross-validation was used during training to avoid overfitting. For example, if the model exhibited excessive pressure difference on a validation set with a high-viscosity material, three additional sets of similar data were added for retraining until the model met the adjustment targets on all validation set conditions. After training, three rounds of small-batch trial molding calibration were performed on an actual mold. For example, for a 12V lead-acid battery box customized for a certain customer, the wall thickness was slightly thin, which made the mold core more sensitive to lateral pressure. Through trial molding, it was found that the k2 adjustment force of the model output was insufficient. It was necessary to fine-tune the width of the Gaussian function of the hidden layer to improve the response speed of the r-side difference exceeding the standard by 20%, and finally ensure that the model can quickly adapt to the product specifications of different customers in actual production.

[0126] After inputting the four types of feature change rates extracted in step 5.4 into the trained model, adaptive pressure adjustment coefficients are generated through a series of logical steps. First, the attention module prioritizes focusing on the mean r-stable area and the side difference r-lateral difference, allocating feature influence according to preset weights. For example, when the mean r-stable area is close to ±0.02mm... 3 When the pressure reaches the critical stable value ( / s), its weight automatically increases to 0.5 to ensure uniform dispensing. Subsequently, the hidden layer uses a Gaussian function to fit the nonlinear relationship between the characteristic rate of change and the adjustment coefficient, and combines this with the viscosity and pressure characteristics of the PP / ABS melt to calculate the basic k1 and k2 values. Finally, the dynamic correction unit optimizes the results based on the characteristic exceeding the limit. If the r-edge exceeds the limit, for example, the rate of change of nozzle #1 is 0.015mm lower than that of nozzle #4... 3 If the value is / s, then the k1 value corresponding to hot nozzle No. 1 will be increased by 0.02 to expand its effective flow channel cross-section; if the r-side difference exceeds the standard, for example, the change rate on the left side is 0.025mm higher than that on the right side. 3 If the value is / s, then the k2 value of the left hot nozzle group will be increased by 0.01 to reduce the melt viscosity by local heating and balance the lateral pressure.

[0127] The generated adjustment coefficients are directly sent to the actuator of the pressure equalization output chamber. k1 controls the micron-level displacement of the flow channel cross-section adjustment component; for example, k1=1.03 corresponds to a 3% increase in the flow channel cross-section. k2 controls the power output of the local electric heating unit; for example, k2=1.01 corresponds to a 1% increase in heating power. The entire adjustment process is completed within 0.1 seconds, ensuring real-time response to pressure changes. Ultimately, the dispensing pressure difference of the seven hot nozzles is stably controlled within ±0.02MPa, and the lateral pressure difference of the mold core is controlled within ±0.01MPa. This solves the mold core offset problem caused by pressure imbalance in traditional solutions, reducing the number of trial moldings from multiple to within three.

[0128] In the embodiments of this invention, the relevant numerical parameters are all exemplary settings and not fixed standards. In practical applications, they can be flexibly adjusted according to specific circumstances such as material properties, mold structure, equipment precision, and product process. The adjustment should aim to ensure balanced hot nozzle pressure and avoid mold core displacement, without changing the core technical concept of this invention, and all such adjustments fall within the protection scope of this invention.

[0129] In a preferred embodiment of the present invention, step 6 above may include:

[0130] Step 6.1: Calculate the corresponding pressure setting parameters based on the adaptive pressure adjustment coefficient. Specifically, the core of calculating the pressure setting parameters is to convert the adaptive pressure adjustment coefficient into specific action commands that the pressure equalization output chamber can execute, closely adhering to the pressure adaptation requirements of the seven hot nozzles and the pressure balance logic for melt remelting. First, considering the initial structural characteristics of the feeding channels of each hot nozzle in the pressure equalization output chamber—the difference between relatively longer flow paths for edge hot nozzles and shorter flow paths for middle hot nozzles—the adjustment parameters are calculated based on the flow channel cross-section fine-tuning coefficient and the pressure loss compensation principle: edge hot nozzles focus on compensating for path loss by expanding the cross-section, while middle hot nozzles focus on maintaining the cross-section. First, surface stability is achieved to avoid pressure superposition. Second, regarding the local temperature compensation coefficient, the temperature distribution pattern of the melt remelting after being diverted by the showerhead is referenced. Combined with the division of the pressure-sensitive area on the side of the mold core, the temperature adjustment parameters are precisely allocated to the corresponding areas: the left hot nozzle group, the right hot nozzle group, and the edge hot nozzle each correspond to an independent temperature adjustment unit, ensuring that temperature compensation can specifically improve the local melt viscosity and assist in pressure transmission balance. Finally, all tuning parameters have been verified through parameter-pressure correlation and the pressure change trend after parameter adjustment has been verified to ensure that each parameter can accurately point to the pressure imbalance problem, providing a scientific and executable basis for subsequent dynamic adjustment.

[0131] Step 6.2 involves introducing the homogeneous melt into the pressure equalization output chamber. Specifically, the process of introducing the homogeneous melt focuses on maintaining stable pressure and ensuring uniform dispersion, precisely aligning the melt state of the secondary equalization chamber with the adjustment requirements of the pressure equalization output chamber. The timing of the introduction strictly matches the completion point of melt mixing and remelting in the secondary equalization chamber. When the melt reaches a molecular-level homogeneous fusion state and the pressure field tends to stabilize, the flow channel is activated to smoothly introduce the melt into the pressure equalization output chamber. The internal structure design of the pressure equalization output chamber deeply follows the principle of showerhead flow distribution, with radial flow channels at the inlet. The channel size is precisely allocated according to the distribution ratio of the seven hot nozzles, ensuring that the melt naturally disperses to the corresponding feeding channels of each hot nozzle after entering the chamber, avoiding excessively high local flow rates or accumulation. During the introduction process, a buffer structure set at the junction of the secondary equalization chamber and the pressure equalization output chamber absorbs the instantaneous impact force of the melt flow, reducing pressure fluctuations. Simultaneously, a constant flow rate of the melt is maintained, ensuring that the melt remains in a stable laminar flow state within the pressure equalization output chamber, creating a foundation for uniform initial pressure and stable flow state for subsequent dynamic adjustment.

[0132] Step 6.3: During the process of the homogeneous melt flowing through the pressure equalization output chamber, the melt pressure is dynamically adjusted through pressure setting parameters to obtain the initially adjusted melt. Specifically, this includes: The dynamic adjustment process is the key to achieving pressure balance among the seven hot nozzles. The core is a closed-loop logic of real-time sensing, precise intervention, and dynamic adaptation, which closely follows the pressure change pattern of melt remelting throughout the process. First, a real-time sensing unit is embedded in the pressure equalization output chamber to continuously monitor the melt's flow rate, pressure distribution, and viscosity changes. The data is dynamically compared with the pressure setting parameters to determine the specific location of the current pressure imbalance, such as low pressure in the left hot nozzle group or insufficient pressure in the No. 1 edge hot nozzle. Second, adjustment actions are executed according to the principle of primary and secondary coordination: flow channel cross-section adjustment is the primary intervention. The method involves using micron-level electric actuators to fine-tune the flow channel of the target hot nozzle in real time according to set parameters: when the pressure is too low, the cross-section is slowly expanded to improve the melt flow efficiency and supplement the pressure; when the pressure is too high, the cross-section is slightly reduced to smoothly release excess pressure. Local temperature compensation is used as an auxiliary means. When lateral pressure imbalance or melt viscosity fluctuations affect pressure transmission, the heating unit in the corresponding area is activated to reduce melt viscosity through precise temperature increase, promoting rapid pressure transmission to the imbalance area. During the adjustment process, a short melt stabilization period is reserved after each action. The next adjustment is carried out only after the pressure change tends to be gradual, avoiding frequent adjustments that may cause pressure field disorder and ensuring that the pressure distribution of the melt gradually converges to an equilibrium state after the initial adjustment.

[0133] Step 6.4 involves real-time pressure equalization verification of the initial melt adjustment. Specifically, this includes: The pressure equalization verification adheres to the principles of comprehensive coverage, accurate judgment, and real-time feedback to ensure that the verification results accurately reflect the dispensing pressure status of the seven hot nozzles and the lateral stability of the mold core. The monitoring point layout for the verification method is precisely planned: pressure sensing points are installed at the material outlet ends of all seven hot nozzles to collect the dispensing pressure data of each hot nozzle in real time; two lateral pressure sensing points are symmetrically set in the key stress areas on both sides of the mold core to collect the total pressure on both sides; simultaneously, one global pressure sensing point is set in the melt fusion area of ​​the pressure equalization output cavity to monitor the overall pressure. Stability; the verification logic is divided into three layers: the first layer compares the pressure difference between the seven hot nozzles to determine if there is any abnormal pressure in a single hot nozzle; the second layer analyzes the lateral pressure difference on both sides of the mold core to assess whether there is any force imbalance that could cause the mold core to shift; the third layer combines global pressure data to determine whether the overall pressure field is stable; all monitoring data are transmitted to the processing unit in real time at a fixed frequency, and instantaneous fluctuation interference is eliminated by sliding mean filtering to ensure the authenticity of the data; at the same time, the processed data is dynamically compared with the preset equilibrium standard to quickly output the verification results of qualified, locally unbalanced, and severely unbalanced, providing a clear basis for subsequent judgment or secondary adjustment.

[0134] Step 6.5: When the verification result meets the preset equalization standard, the initially adjusted melt is determined to be a pressure-equalized melt. Specifically, the determination process for a pressure-equalized melt focuses on meeting injection molding requirements and ensuring mold core stability, strictly connecting the verification result with the subsequent injection molding process. The preset equalization standard is based on the core technical objectives of this invention, requiring not only that the discharge pressure difference of the seven hot nozzles be within a reasonable range, but also emphasizing that the lateral pressure difference on both sides of the mold core be controlled within a safe threshold. Furthermore, this stable state must be maintained for at least three data acquisition cycles, excluding instantaneous compliance. When the verification result shows three layers of monitoring indicators… When all standards are met, the system automatically determines that the initial melt is a pressure-balanced melt and triggers subsequent delivery commands. After the determination is completed, the pressure-balanced melt is further stabilized by the pressure-stabilizing structure at the end of the pressure equalization output chamber, and then precisely and evenly injected into the injection cavity of the 12V lead-acid battery box along the dedicated material supply channels of the 7 hot nozzles. The entire determination and delivery process is seamlessly connected, ensuring that the melt is injected under pressure balance, thereby avoiding problems such as mold core displacement and uneven product molding caused by pressure imbalance from the root, directly ensuring the rapid mold delivery requirements, and reducing the number of parameter adjustments during the trial molding process.

[0135] In a preferred embodiment of the present invention, step 7 above may include:

[0136] Step 7.1: Receive the pressure-equalized melt and introduce it into the pressure equalization output chamber. This includes: receiving the determined pressure-equalized melt; before receiving, verifying the melt's pressure uniformity and fusion state a second time through a pre-monitoring point at the inlet of the pressure equalization output chamber: ensuring complete molecular-level fusion of the melt, no local viscosity differences, and overall pressure fluctuations controlled within a safe range to avoid disrupting the equalization state due to minor disturbances during transport; during introduction, continuing the core logic of uniform distribution from the showerhead, the pressure equalization output chamber inlet is equipped with an annular guide structure corresponding to the diversion orifice. This structure further disperses the melt through multiple small guide holes before it flows into the chamber, maintaining pressure equalization while preventing the melt from directly impacting the chamber wall and generating eddies; the introduction path adopts a gradual design, smoothly transitioning from the connecting channel to the inner diameter of the pressure equalization output chamber without abrupt corners, reducing flow resistance and pressure loss; simultaneously maintaining a constant introduction flow rate to ensure the melt forms a stable laminar flow state within the chamber, providing a preliminary guarantee for the uniform distribution of the seven output channels.

[0137] Step 7.2: At the outlet of the pressure equalization output chamber, the pressure equalization melt is simultaneously received through multiple equally spaced output channels. Specifically, the outlet of the pressure equalization output chamber adopts an annular equidistant + structurally homogeneous design. The seven output channels are symmetrically distributed around the center of a circle, and the included angle between the centers of adjacent channels precisely matches the layout spacing of the seven hot nozzles, ensuring that the path length from each channel to the corresponding hot nozzle is completely consistent. The structural parameters of the channels themselves are strictly uniform: the inner diameter tolerance is controlled within a very small range, and the inner wall is precision polished to reduce frictional resistance. The turning angles and radii of curvature are exactly the same, eliminating pressure and velocity deviations caused by path differences from a structural perspective. Each channel has a horn-shaped buffer groove at its inlet, which smoothly connects to the inner wall of the pressure equalization output chamber. The volume and shape of the buffer groove have been optimized through mold flow analysis, which can effectively absorb the instantaneous impact force of the melt flow and avoid pressure fluctuations caused by local throttling. A turbulence suppression zone is also provided in the middle section of the channel to prevent the melt from forming turbulence during the flow process, ensuring that the melt in all channels flows in a stable laminar state, laying a structural foundation for synchronous distribution.

[0138] Step 7.3 involves real-time monitoring of the melt pressure and velocity in each output channel to ensure they meet synchronous distribution conditions. Specifically, this includes: embedding a high-precision monitoring unit in the middle section of each output channel; selecting monitoring points to avoid channel bends and turbulence-prone areas to ensure the collected data accurately reflects the critical state of the melt before it enters the hot nozzle; the monitoring unit simultaneously collects two core indicators: the melt's static pressure and instantaneous velocity, with the collection frequency consistent with the previous pressure field monitoring frequency to ensure data synchronization; the monitoring logic employs a dual verification mechanism: firstly, single-channel indicator verification, where the pressure and velocity of each channel must be within the pre-defined range. The system employs several mechanisms: first, setting a reasonable range; second, verifying the consistency of multiple flow channels, ensuring that the pressure and velocity differences between any two channels are kept within a very small range, and that the average pressure and velocity of all seven channels meet the requirements for synchronous distribution; if a slight deviation occurs, the built-in micro-adjustment components of the flow channels will respond immediately: when the pressure is too low, the adjustment components slightly reduce the cross-sectional area of ​​the flow channel to increase the local pressure; when the velocity is too slow, the flow direction is adjusted by micro-guide vanes on the inner wall of the flow channel to accelerate the velocity; the fine-tuning process adopts a small-amplitude, gradual principle to avoid excessive single adjustment that could disrupt the overall balance, ensuring that the melt state of all channels quickly converges to the synchronous distribution standard.

[0139] Step 7.4: When the synchronization distribution conditions are met, the pressure-equalizing melt is synchronously injected into the odd number of hot nozzles of the mold through each output channel. Specifically, this includes: when multiple consecutive acquisition cycles confirm that the pressure and flow rate of all output channels meet the synchronization distribution standards and there are no significant fluctuations, a unified synchronization injection command is triggered; the outlet valves of all output channels are opened simultaneously, with the opening time difference controlled at the microsecond level, to ensure that the 7 hot nozzles receive the melt injection completely synchronously; the connection between the output channel and the hot nozzle needs to be strictly sealed, and the sealing surface is precision ground to ensure the connection is sealed to prevent melt leakage and reduce the flow resistance at the connection to avoid pressure loss; during the injection process, the pressure stabilizing structure of the pressure equalizing output chamber works continuously to compensate for the natural loss during the melt flow process by real-time pressure replenishment, maintaining the pressure stability in the output channel; at the same time, considering the characteristics of the thin and high mold core and its sensitivity to lateral pressure, the direction of the injection pressure is precisely calibrated to ensure that the lateral force generated during melt injection cancels each other out and does not generate off-center load, thus avoiding mold core offset from the root.

[0140] Step 7.5: Continuously verify the pressure consistency at each hot runner inlet during the injection molding process to ensure pressure balance is maintained until filling is complete. Specifically, this includes: continuously collecting data from pressure monitoring points at the hot runner inlets throughout the entire injection filling process. The verification logic is divided into two levels: individual consistency and group balance. Individual consistency verification: Real-time comparison of the pressure values ​​at the seven hot runner inlets ensures that the pressure difference between any two hot runners remains within a preset reasonable range. Group balance verification: Dividing the seven hot runners into three groups (left, middle, and right), and calculating the total pressure difference between the left and right groups in real-time to ensure balanced force on both sides of the mold core and avoid lateral pressure imbalance leading to displacement. The monitoring data is transmitted to the control unit in real-time. If melt consumption or slight temperature changes occur, the control unit will be notified. Fluctuations cause slight pressure deviations, which the control unit then coordinates with the dynamic adjustment structure of the pressure equalization output chamber and the flow channel fine-tuning components to provide targeted compensation: when the pressure of a single hot nozzle is too low, the cross-section or local temperature of the corresponding output flow channel is fine-tuned; when there is a lateral pressure imbalance, the injection pressure of the corresponding hot nozzle is adjusted to assist in balancing; the compensation response speed is adapted to the melt flow rhythm in real time to ensure that the pressure balance is maintained throughout the entire filling process until the mold cavity is completely filled and the melt forms a stable molding pressure; the entire continuous verification and compensation process effectively avoids uneven product molding caused by pressure decay or fluctuations in the later stages of filling, ensuring that the mold can be stably produced without multiple trial molding adjustments, echoing the core beneficial effects of this invention: rapid mold delivery and reduced debugging costs.

[0141] like Figure 2 As shown, embodiments of the present invention also provide a hot runner control system for injection molds based on multi-hole flow distribution pressure equalization, including:

[0142] The initial collection module is used to inject molten plastic into the primary distribution chamber to form a collected melt; the collected melt is then passed through a multi-component flow orifice located between the primary distribution chamber and the secondary equalization chamber, thereby transforming the collected melt into a multi-stream flow melt.

[0143] The mixing and remelting module is used to introduce multiple streams of melt into a secondary equalization chamber, where the multiple streams of melt are mixed and remelted to form a homogeneous melt.

[0144] The deployment and acquisition module is used to arrange multiple dynamic pressure acquisition points at specific geometric locations in the secondary equalization cavity based on the formation of a homogeneous melt. The specific geometric locations include at least the center point of the inner wall near the gate, the center point of the inner wall far from the gate, and two side wall monitoring points symmetrically distributed along the radial direction, and to simultaneously acquire real-time pressure data from each dynamic pressure acquisition point.

[0145] The construction and calculation module is used to construct a three-dimensional pressure field isosurface volume characterizing the transient pressure distribution in the secondary equilibrium cavity based on real-time pressure data; calculate the volume change rate of the three-dimensional pressure field isosurface volume; and generate an adaptive pressure adjustment coefficient based on the volume change rate.

[0146] The pressure setting module is used to guide the homogeneous melt to the pressure equalization output chamber, and perform adjustable pressure setting on the homogeneous melt in the pressure equalization output chamber based on the adaptive pressure adjustment coefficient, thereby obtaining a pressure-equalized melt.

[0147] The synchronous distribution module is used to synchronously distribute the pressure-equalizing melt to an odd number of hot nozzles of the mold through multiple output channels connected to the pressure equalization output chamber.

[0148] To ensure accurate understanding by those skilled in the art, the relevant terms and core concepts in this document are explained as follows:

[0149] The center point of the inner wall near the gate and the center point of the inner wall far from the gate: In specific implementation, these are also referred to as the near-end point and the far-end point, respectively, and they refer to the same location. Asymmetrical but flow-balanced arrangement: Specifically, the number of flow dividers is, for example, more than 9, than the number of hot nozzles, for example, 7. Some of the flow dividers, for example, 7, correspond to the hot nozzle feeding path, while the remaining flow dividers, for example, 2, serve as a balancing redundancy. Through the coordinated design of the flow rates of each hole, the flow rate and pressure balance of the multi-stream melt is ultimately achieved.

[0150] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for controlling the hot runner of injection molds based on multi-hole flow distribution pressure equalization, characterized in that, The method includes: Molten plastic is injected into the primary distribution chamber to form a pooled melt; the pooled melt is then passed through a multi-component flow orifice located between the primary distribution chamber and the secondary equalization chamber, thereby transforming the pooled melt into a multi-streamed melt. The multi-stream melt is introduced into the secondary equalization chamber, where it is mixed and remelted to form a homogeneous melt. Based on the formation of a homogeneous melt, multiple dynamic pressure acquisition points are arranged at specific geometric locations in the secondary equalization cavity. The specific geometric locations include at least the center point of the inner wall near the gate, the center point of the inner wall far from the gate, and two side wall monitoring points symmetrically distributed along the radial direction. Real-time pressure data of each dynamic pressure acquisition point are collected simultaneously. Based on real-time pressure data, a three-dimensional pressure field isosurface volume characterizing the transient pressure distribution within a secondary equilibrium cavity is constructed. Calculate the volume change rate of the three-dimensional pressure field isosurface and generate an adaptive pressure adjustment coefficient based on the volume change rate; The homogeneous melt is led to the pressure equalization output chamber, and an adjustable pressure setting is performed on the homogeneous melt in the pressure equalization output chamber based on the adaptive pressure adjustment coefficient, thereby obtaining a pressure-equalized melt. By connecting multiple output channels of the equalizing output chamber, the pressure-equalizing melt is synchronously distributed to an odd number of hot nozzles in the mold; the continuous melt is evenly divided into 9 independent streams, of which 7 streams are adapted to the subsequent hot nozzle feeding paths, and the 2 redundant streams naturally merge with other melts after entering the secondary equalizing chamber; of the 9 streams from the multiple streams, 7 core melts correspond to the feeding needs of 7 hot nozzles, and 2 redundant melts are used for equalization compensation; the flow trajectory of the 9 melts is positioned and machined by the reference surface of the mold cavity, the trajectory of the core melt is aligned with the feeding channels of the 7 hot nozzles, and the trajectory of the redundant melt fills the gaps between the core melts.

2. The injection mold hot runner control method based on multi-hole flow distribution pressure equalization according to claim 1, characterized in that, Molten plastic is injected into the primary distribution chamber to form a pooled melt; The process involves allowing the collected melt to pass through a multi-component flow orifice located between the primary distribution chamber and the secondary equalization chamber, thereby transforming the collected melt into a multi-stream split melt, including: Molten plastic from the injection molding machine nozzle is introduced into the primary distribution chamber through the main flow path, so that the molten plastic forms an initial aggregate melt in the primary distribution chamber; The pressure in the primary distribution chamber is monitored in real time, and the chamber pressure is compared with the preset inlet pressure threshold to obtain the comparison result; Based on the comparison results, the melt flow rate of the main channel is dynamically adjusted so that the initial collected melt is stabilized within a preset pressure range, forming a pressure-stable collected melt. The pressure-stable collected melt is driven to flow through a multi-component flow orifice, wherein the multi-component flow orifice is arranged in an asymmetrical but flow-balanced manner through the partition between the primary distribution chamber and the secondary equalization chamber. Through the throttling and guiding effect of the multi-component flow orifice, the pressure-stable aggregated melt is uniformly divided into multiple streams of melt with similar flow rates and pressures.

3. The injection mold hot runner control method based on multi-hole flow distribution pressure equalization according to claim 2, characterized in that, A multi-stream melt is introduced into a secondary equalization chamber, where it is mixed and remelted to form a homogeneous melt, comprising: Multiple streams of melt with similar flow rates and pressures from the multi-component flow orifice are guided into the inlet region of the secondary equalization chamber at a preset inlet angle. Within the inlet area, a flow guiding structure is set up to cause the multi-stream split melts to initially converge and exchange momentum, thereby forming an initial converged melt. The primary flow of the initial confluence of melts into the main mixing zone of the secondary equalization chamber is driven. Within the main mixing zone, the turbulence effect generated by the geometry of the chamber promotes thorough shear mixing and heat exchange between the multiple melt streams. Real-time monitoring of melt temperature and viscosity within the main mixing zone ensures it remains within the preset remelting process window; Under the condition of meeting the remelting process window, the fully mixed melt completes the final thermal homogenization and molecular chain reconstruction at the end of the main mixing zone, forming a homogeneous melt with uniform physical properties.

4. The injection mold hot runner control method based on multi-hole flow distribution pressure equalization according to claim 3, characterized in that, Based on the formation of a homogeneous melt, multiple dynamic pressure acquisition points are arranged at specific geometric locations in the secondary equalization cavity. These specific geometric locations include at least the center point of the inner wall near the gate, the center point of the inner wall far from the gate, and two sidewall monitoring points symmetrically distributed radially. Real-time pressure data from each dynamic pressure acquisition point is collected synchronously, including: On the inner wall of the secondary equalization chamber, a set of key sampling points for characterizing dynamic pressure distribution are selected; the key sampling points include at least a proximal point near the center of the inner wall on the side close to the inlet of the diversion hole, a distal point far from the center of the inner wall on the side far from the inlet of the diversion hole, and a pair of lateral points located on both sides of the chamber and symmetrically distributed with respect to the central axis of the chamber. High-response miniature pressure sensors are installed at each key acquisition point to construct a multi-point pressure sensing array that matches the cavity structure. When the homogeneous melt flows through the secondary equalization chamber, the multi-point pressure sensing array is activated simultaneously. The instantaneous melt pressure signal at each key acquisition point is collected in real time and synchronously through a multi-point pressure sensor array. The instantaneous pressure signals collected at each point are synchronized to generate a set of original datasets of cavity dynamic pressure with spatiotemporal correlation.

5. The injection mold hot runner control method based on multi-hole flow distribution pressure equalization according to claim 4, characterized in that, Based on real-time pressure data, a three-dimensional pressure field isosurface volume characterizing the transient pressure distribution within the secondary equilibrium cavity is constructed, including: Obtain the raw dataset of dynamic pressure in the cavity; Based on the spatial coordinates of key acquisition points, spatial interpolation calculations are performed on the instantaneous pressure signals in the raw dynamic pressure dataset of the cavity to generate a spatial pressure distribution function covering the entire inner cavity of the secondary equalization cavity. Based on the spatial pressure distribution function, a transient pressure field point cloud reflecting the pressure values ​​at various points within the cavity at the same moment is reconstructed in a three-dimensional coordinate system. Isosurface extraction and surface fitting are performed on the transient pressure field point cloud to construct a three-dimensional pressure field isosurface volume that characterizes the transient pressure distribution in the current injection molding cycle.

6. The injection mold hot runner control method based on multi-hole flow distribution pressure equalization according to claim 5, characterized in that, Calculating the volume change rate of the three-dimensional pressure field isosurface and generating an adaptive pressure adjustment coefficient based on the volume change rate, including: Obtain the three-dimensional pressure field contour volume at multiple consecutive moments within the current injection molding cycle; Calculate the instantaneous volume of the three-dimensional pressure field isosurface at each consecutive moment, and generate a set of volume values ​​arranged in a time series; Based on the volume values ​​arranged in a time series, the ratio of the change in volume values ​​at adjacent times to the time interval is calculated, thereby obtaining the volume change rate sequence. Extract characteristic rates of change that characterize the dynamic evolution trend of the pressure field from the volume change rate sequence; The characteristic rate of change is input into a preset adjustment coefficient mapping model. Through the nonlinear transformation of the preset adjustment coefficient mapping model, an adaptive pressure adjustment coefficient is generated to adjust the working state of the pressure equalization output chamber.

7. The injection mold hot runner control method based on multi-hole flow distribution pressure equalization according to claim 6, characterized in that, The homogeneous melt is directed to the pressure equalization output chamber, and an adjustable pressure setting is performed on the homogeneous melt within the pressure equalization output chamber based on an adaptive pressure adjustment coefficient, thereby obtaining a pressure-equalized melt, including: The corresponding pressure tuning parameters are calculated based on the adaptive pressure regulation coefficient. The homogeneous melt is introduced into the pressure equalization output cavity; During the process of the homogeneous melt flowing through the pressure equalization output chamber, the melt pressure is dynamically adjusted by the pressure setting parameters to obtain the initially regulated melt. Real-time pressure equalization verification was performed on the initially regulated melt. When the verification results meet the preset equilibrium criteria, the initially adjusted melt is determined to be a pressure-equilibrium melt.

8. The injection mold hot runner control method based on multi-hole flow distribution pressure equalization according to claim 7, characterized in that, By connecting multiple output channels to the pressure equalization output chamber, the pressure-equalizing melt is synchronously distributed to an odd number of hot nozzles in the mold, including: Receive the pressure equalization melt and introduce it into the pressure equalization output chamber; At the outlet of the pressure equalization output chamber, the pressure equalization melt is simultaneously received through multiple equally spaced output channels. Real-time monitoring of melt pressure and flow rate in each output channel to ensure that they meet the synchronous distribution conditions; When the synchronous distribution conditions are met, the pressure-equalizing melt is synchronously injected into the odd number of hot nozzles of the mold through each output channel; During the injection molding process, the pressure consistency at each hot runner inlet is continuously verified to ensure that the pressure balance is maintained until filling is complete.

9. A hot runner control system for injection molds based on multi-hole flow distribution pressure equalization, wherein the system implements the method as described in any one of claims 1 to 8, characterized in that, include: The initial collection module is used to inject molten plastic into the primary distribution chamber to form a collected melt; The collected melt is passed through a multi-component flow orifice located between the primary distribution chamber and the secondary equalization chamber, thereby transforming the collected melt into a multi-stream flow melt. The mixing and remelting module is used to introduce multiple streams of melt into a secondary equalization chamber, where the multiple streams of melt are mixed and remelted to form a homogeneous melt. The deployment and acquisition module is used to arrange multiple dynamic pressure acquisition points at specific geometric locations in the secondary equalization cavity based on the formation of a homogeneous melt. The specific geometric locations include at least the center point of the inner wall near the gate, the center point of the inner wall far from the gate, and two side wall monitoring points symmetrically distributed along the radial direction, and to simultaneously acquire real-time pressure data from each dynamic pressure acquisition point. The construction and calculation module is used to construct a three-dimensional pressure field isosurface volume characterizing the transient pressure distribution in the secondary equilibrium cavity based on real-time pressure data; calculate the volume change rate of the three-dimensional pressure field isosurface volume; and generate an adaptive pressure adjustment coefficient based on the volume change rate. The pressure setting module is used to guide the homogeneous melt to the pressure equalization output chamber, and perform adjustable pressure setting on the homogeneous melt in the pressure equalization output chamber based on the adaptive pressure adjustment coefficient, thereby obtaining a pressure-equalized melt. The synchronous distribution module is used to synchronously distribute the pressure-equalizing melt to an odd number of hot nozzles of the mold through multiple output channels connected to the pressure equalization output chamber.

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