A partition differentiated cooling method for an automobile lampshade mold
By using a zoned differentiated cooling method, the problems of internal stress in the thin-walled area and shrinkage marks in the thick-walled area during the cooling process of automotive lamp cover molds were solved, achieving efficient cooling cycles and improved molding quality, thus adapting to the high-speed mass production of automotive parts.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SUZHOU ZHENYI MOULD CO LTD
- Filing Date
- 2026-05-31
- Publication Date
- 2026-07-24
AI Technical Summary
In the existing technology, the integral cooling method of automotive lamp cover mold cannot simultaneously control the internal stress of the thin-walled optical area and efficiently cool the thick-walled structural area, resulting in a longer injection molding cycle. The thin-walled area is prone to internal stress defects, and the thick-walled area is prone to shrinkage marks, affecting molding quality and efficiency.
A zoned differential cooling method is adopted, dividing the mold cavity into a thin-walled optical zone and a thick-walled structural zone, and configuring active thermal compensation and enhanced cooling circuits respectively. Through real-time temperature control and temperature difference adjustment, the high temperature of the thin-walled zone is maintained and the temperature of the thick-walled zone is rapidly cooled. Combined with the buffer cooling zone to smooth the temperature gradient, the cooling process is controlled in a coordinated manner.
While ensuring optical quality and low stress in the thin-walled area, the cooling cycle is shortened, molding quality and production efficiency are improved, and the high-speed mass production requirements of automotive parts are met.
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Figure CN122442899A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of temperature control technology for injection molds of automotive parts, and in particular to a method for differentiated cooling of automotive lamp cover molds. Background Technology
[0002] As a key aesthetic and functional component of automotive lighting systems, automotive lamp covers are typically manufactured using injection molding. The molded parts of these covers exhibit significant structural inhomogeneity: the lens area is a thin-walled optical surface, requiring extremely high surface quality, light transmittance, and internal stress distribution; while the mounting feet, clips, and reinforcing ribs are thick-walled structures, with thickness differences reaching several times. This structural characteristic places stringent demands on mold temperature control during the injection molding process.
[0003] In traditional injection molding cooling processes, molds typically employ an integral cooling channel design, applying the same cooling conditions to all areas of the cavity. However, due to the inherent difference in heat dissipation rates between thin-walled and thick-walled areas, integral cooling often leads to shrinkage defects such as shrinkage marks and cavities in thick-walled areas due to slow cooling. Simultaneously, the thin-walled optical areas experience premature cooling and solidification, resulting in significant internal stress and causing optical quality issues such as rainbow patterns and warping. To ensure sufficient solidification in thick-walled areas, the overall cooling time must be extended, directly increasing injection molding cycles and reducing production efficiency. While existing technologies offer improved solutions such as zoned cooling, which use independent cooling channels for different areas to achieve differentiated cooling, these solutions typically focus only on improving cooling efficiency, failing to adequately consider the stress issues caused by premature cooling in thin-walled optical areas, and lacking a coordinated control mechanism for the cooling processes of thin-walled and thick-walled areas.
[0004] Therefore, how to achieve efficient cooling of thick-walled structural regions while ensuring the surface quality and low stress state of thin-walled optical regions is a technical problem that urgently needs to be solved in this field. Summary of the Invention
[0005] This application provides a zoned differential cooling method for automotive lamp cover molds. This method achieves improved molding quality and production efficiency of automotive lamp covers by synergistic control of active thermal compensation in the thin-walled optical zone and enhanced cooling in the thick-walled structural zone, thereby eliminating stress defects in the optical zone and shrinkage marks in the thick-walled zone.
[0006] In a first aspect, a method for differentiated cooling of automotive lamp cover molds is provided, wherein the automotive lamp cover plastic part includes a thin-walled optical functional area and a thick-walled mounting structure area, the method comprising: S1: The mold cavity is divided into a first temperature control zone and a second temperature control zone. The first temperature control zone corresponds to the thin-walled optical functional zone, and the second temperature control zone corresponds to the thick-walled mounting structure zone. The first temperature control zone is equipped with an active heating unit and a cooling circuit, and the second temperature control zone is equipped with an enhanced cooling circuit. S2: During the cooling stage, active thermal compensation is implemented in the first temperature control zone to maintain the cavity temperature of the first temperature control zone within a preset high temperature range; at the same time, enhanced cooling is implemented in the second temperature control zone to rapidly cool down the second temperature control zone. S3: Real-time acquisition of the actual cavity temperature of the first temperature control zone and the second temperature control zone, with the goal of the cavity temperature difference between the first temperature control zone and the second temperature control zone converging to within a preset threshold, and adjustment of the heating power of the active heating unit and the cooling medium flow rate of the enhanced cooling circuit; S4: When the cavity temperatures of the first temperature control zone and the second temperature control zone both reach the ejection temperature range of the plastic part, stop active thermal compensation and enhanced cooling, and open the mold for ejection.
[0007] It should be understood that this application addresses the inherent pain points in the automotive headlight housing plastic parts industry, such as the significant difference in wall thickness between the thin-walled optical functional area and the thick-walled mounting structure area, and the inability of traditional cooling processes to simultaneously address shrinkage mark prevention, internal stress control, and efficiency improvement. Based on the product's structural characteristics, the mold cavity is divided into two independent temperature-controlled zones. During the cooling stage, active thermal compensation is implemented for the thin-walled optical area to maintain its cavity temperature within a preset high-temperature range, preventing premature cooling and solidification that could lead to internal stress. Simultaneously, enhanced cooling is implemented for the thick-walled mounting structure area to rapidly cool it down, eliminating shrinkage marks and shortening the setting time. This method ensures both the optical performance and structural quality requirements of the plastic part while significantly shortening the injection molding cycle, thus meeting the high-cycle, high-yield mass production demands of automotive parts.
[0008] In conjunction with the first aspect, in some implementations of the first aspect, the mold cavity further includes a third temperature control zone, which is located between the first temperature control zone and the second temperature control zone and is equipped with a buffer cooling circuit; during the cooling stage, the third temperature control zone is subjected to medium flow cooling to buffer the temperature gradient between the first temperature control zone and the second temperature control zone.
[0009] It should be understood that this application adds a third temperature control zone with an independent buffer cooling circuit between the first and second temperature control zones. This creates a temperature buffer zone between the high-temperature maintenance area of the thin-walled optical zone and the enhanced cooling area of the thick-walled structural zone. This smoothly connects the temperature difference between the first and second temperature control zones, forming a continuous and stable temperature gradient. It effectively blocks heat conduction crosstalk between the first and second temperature control zones through the mold matrix. This avoids interference from the enhanced cooling of the second temperature control zone on the constant-temperature thermal compensation of the first temperature control zone, ensuring the stability of the mold temperature and the internal stress control effect of the thin-walled optical zone. It also prevents the high temperature of the first temperature control zone from being conducted to the thick-walled area, thus weakening the anti-shrinkage effect of the enhanced cooling. Simultaneously, it allows for uniform and stable cooling and solidification in the gradually thickening areas of the plastic part, avoiding localized internal stress concentration, warping deformation, and temperature difference stress defects on the optical surface caused by temperature jumps, further improving the consistency of the molded part's quality and the stability of the mass production process.
[0010] In conjunction with the first aspect, in some implementations of the first aspect, the control objective includes: In the initial stage of cooling, the cavity temperatures of the first temperature control zone and the second temperature control zone are reduced synchronously, and the temperature reduction rate of the first temperature control zone is less than that of the second temperature control zone; when the cavity temperature difference is less than a preset threshold, the temperature reduction rate of the first temperature control zone is controlled to be consistent with that of the second temperature control zone.
[0011] It should be understood that this application implements phased differentiated cooling rate control for the dual temperature control zones during the cooling stage: in the early stage of the cooling stage, the temperature drop rate of the thin-walled optical zone (first temperature control zone) is made less than that of the thick-walled structural zone (second temperature control zone), ensuring that the thin-walled zone is maintained in a high-temperature range above the glass transition temperature of the material to fully release internal stress, while the thick-walled zone cools down rapidly to eliminate the risk of shrinkage marks; when the temperature difference between the two zones narrows to a preset threshold, the cooling rates of the two zones are made to be consistent, thereby guiding the two zones to maintain synchronous contraction in the subsequent cooling process and avoiding warping deformation caused by asynchronous contraction.
[0012] In conjunction with the first aspect, in some implementations of the first aspect, the preset high temperature range is set according to the glass transition temperature of the injection molding material, and the lower limit of the preset high temperature range is higher than the glass transition temperature; the active thermal compensation maintains the cavity temperature of the first temperature control zone at no lower than the glass transition temperature throughout the cooling stage, until the cavity temperature of the second temperature control zone drops to the ejection temperature range.
[0013] It should be understood that the glass transition temperature is the characteristic temperature at which polymer materials transition between the glassy and elastic states, and it is the critical point at which the molecular chain segments of injection-molded materials begin to undergo significant movement. When the material temperature is above the glass transition temperature, the molecular chain segments can move freely, and the orientation stress and thermal stress generated during injection molding can be effectively relaxed. However, when the temperature drops below the glass transition temperature, the molecular chain segments are frozen, and the internal stress will be locked inside the product and difficult to eliminate. Based on this characteristic, this application sets the lower limit of the preset high temperature range of the first temperature control zone to be higher than the glass transition temperature of the injection-molded material, and maintains the cavity temperature of this region at no lower than the glass transition temperature through active thermal compensation throughout the cooling stage, until the thick-walled structure region of the second temperature control zone completes the main cooling and drops to near the ejection temperature range, and then simultaneously controls the first temperature control zone to cool down smoothly to the ejection temperature range. This control method ensures that the thin-walled optical region remains in a highly elastic state throughout the entire cooling process, allowing the orientation stress generated by injection filling and holding pressure, as well as the thermal stress generated during cooling, to be fully relaxed and eliminated. This avoids optical defects such as rainbow patterns and birefringence caused by premature cooling and solidification, while not affecting the enhanced cooling process of the thick-walled region, thus achieving a synergistic match between optical quality and molding efficiency.
[0014] In conjunction with the first aspect, in some implementations of the first aspect, the buffer cooling circuit of the third temperature control zone adopts a gradually spaced conformal water channel, and the arrangement spacing of the gradually spaced conformal water channel is gradually adjusted from the first temperature control zone to the second temperature control zone to form a continuous and smooth temperature gradient; heat insulation structures are provided at the partition boundaries between the third temperature control zone and the first and second temperature control zones.
[0015] In conjunction with the first aspect, in some implementations of the first aspect, step S3 includes: Within each temperature control zone, the surface temperature near the cavity surface and the deep temperature near the cooling circuit or heating unit are collected respectively; the control target includes: the surface temperature difference converges to a first preset threshold, and the deep temperature difference converges to a second preset threshold.
[0016] It should be understood that the first preset threshold refers to the upper limit of the allowable surface temperature difference between the first and second temperature control zones. Surface temperature, i.e., the temperature collected near the cavity surface, directly determines the surface quality, shrinkage uniformity, and optical performance of the plastic part. When the surface temperature difference between the two zones converges to within the first preset threshold, it means that the thermal state of the thin-walled optical zone and the thick-walled structural zone at the cavity surface, a key interface, tends to be consistent, thereby ensuring that the lampshade's appearance is free from gloss differences, flow marks, or warping deformation caused by temperature differences. The second preset threshold refers to the upper limit of the allowable deep temperature difference between the first and second temperature control zones. Deep temperature, i.e., the temperature collected near the cooling circuit or heating unit, reflects the heat accumulation and thermal equilibrium state inside the mold steel. When the deep temperature difference between the two zones converges to within the second preset threshold, it indicates that the overall thermal distribution of the mold tends to be stable, avoiding excessive thermal stress or thermal fatigue damage inside the mold matrix caused by zoned temperature control, while providing stable thermal boundary conditions for the next injection molding cycle.
[0017] In conjunction with the first aspect, in some implementations of the first aspect, step S3 further includes: Temperature control is achieved by using a closed-loop regulation algorithm. During the regulation process, the cavity temperature in the first temperature control zone is always kept no lower than that in the second temperature control zone. Simultaneously, cross-zone temperature distribution data of the mold substrate is collected. Based on the pre-constructed heat conduction model of the mold substrate, feedforward compensation correction is performed on the heating power of the active heating unit and the cooling medium flow rate of the enhanced cooling circuit to offset the temperature fluctuations caused by heat conduction crosstalk between the two temperature control zones.
[0018] In conjunction with the first aspect, in some implementations of the first aspect, before the cooling stage, there are also a mold filling stage and a pressure holding stage: the mold filling stage controls the cavity temperature of both the first temperature control zone and the second temperature control zone to rise to a temperature that matches the preset high temperature range of the first temperature control zone; the pressure holding stage maintains the cavity temperature of the first temperature control zone stable and gradually cools the cavity temperature of the second temperature control zone; before the end of the pressure holding stage, the freezing state of the cavity gate is monitored in real time, and when the gate reaches the critical freezing state, the pre-enhanced cooling of the second temperature control zone is started in advance, while maintaining the thermal compensation state of the first temperature control zone, so as to achieve a seamless connection between the end of the pressure holding stage and the core control of the cooling stage. Attached Figure Description
[0019] Figure 1 This application provides a flowchart of a method for implementing differentiated cooling of automotive lamp cover molds in different zones. Detailed Implementation
[0020] The terminology used in the following embodiments is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. As used in the specification and appended claims of this application, the singular expressions “a,” “an,” “the,” “the,” and “this” are intended to also include expressions such as “one or more,” unless the context clearly indicates otherwise. It should also be understood that in the following embodiments of this application, “at least one” and “one or more” refer to one, two, or more than two. The term “and / or” is used to describe the relationship between related objects, indicating that three relationships can exist; for example, A and / or B can indicate: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character “ / ” generally indicates that the preceding and following related objects are in an “or” relationship.
[0021] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.
[0022] In automotive headlight lens injection molding, the lens area is a thin-walled optical surface, requiring extremely high surface quality and internal stress control. In contrast, the mounting feet and clips are thick-walled structures with significant thickness differences. With traditional monolithic cooling methods, the thick-walled area is prone to shrinkage marks due to slow cooling, while the thin-walled area suffers from premature solidification, freezing internal stress and causing defects such as rainbow patterns and warping. To ensure sufficient solidification in the thick-walled area, the cooling cycle is often extended, impacting efficiency. Existing zoned cooling solutions primarily focus on improving cooling efficiency, neglecting the stress issues in the thin-walled area and lacking coordinated control of the cooling processes in both zones.
[0023] Therefore, how to achieve efficient cooling of the thick-walled region while ensuring the quality and low stress of the thin-walled region is a technical problem that urgently needs to be solved in this field.
[0024] This application provides a method for differentiated cooling of automotive lamp cover molds, which can effectively overcome the above-mentioned problems.
[0025] The technical solutions provided in the embodiments of this application will be described below with reference to the accompanying drawings.
[0026] Figure 1This application provides a flowchart of a method for implementing differentiated cooling of automotive lamp cover molds in different zones.
[0027] refer to Figure 1 In some examples, the automotive lamp cover plastic part includes a thin-walled optical functional area and a thick-walled mounting structure area, and the method includes: S1: The mold cavity is divided into a first temperature control zone and a second temperature control zone. The first temperature control zone corresponds to the thin-walled optical functional zone, and the second temperature control zone corresponds to the thick-walled mounting structure zone. The first temperature control zone is equipped with an active heating unit and a cooling circuit, and the second temperature control zone is equipped with an enhanced cooling circuit. S2: During the cooling stage, active thermal compensation is implemented in the first temperature control zone to maintain the cavity temperature of the first temperature control zone within a preset high temperature range; at the same time, enhanced cooling is implemented in the second temperature control zone to rapidly cool down the second temperature control zone. S3: Real-time acquisition of the actual cavity temperature of the first temperature control zone and the second temperature control zone, with the goal of the cavity temperature difference between the first temperature control zone and the second temperature control zone converging to within a preset threshold, and adjustment of the heating power of the active heating unit and the cooling medium flow rate of the enhanced cooling circuit; S4: When the cavity temperatures of the first temperature control zone and the second temperature control zone both reach the ejection temperature range of the plastic part, stop active thermal compensation and enhanced cooling, and open the mold for ejection.
[0028] In some examples, the mold cavity further includes a third temperature control zone located between the first and second temperature control zones and equipped with a buffer cooling circuit; during the cooling phase, the third temperature control zone is subjected to medium flow cooling to buffer the temperature gradient between the first and second temperature control zones.
[0029] In some examples, the control objectives include: In the initial stage of cooling, the cavity temperatures of the first temperature control zone and the second temperature control zone are reduced synchronously, and the temperature reduction rate of the first temperature control zone is less than that of the second temperature control zone; when the cavity temperature difference is less than a preset threshold, the temperature reduction rate of the first temperature control zone is controlled to be consistent with that of the second temperature control zone.
[0030] In one possible implementation, the control objective can be achieved through a closed-loop control algorithm. The controller acquires real-time feedback values from temperature sensors embedded on the cavity surfaces of the first and second temperature control zones, and calculates the real-time temperature drop rate for each zone. During the initial period after the cooling phase begins, the controller sets the target cooling rate for the first temperature control zone to a first rate value and the target cooling rate for the second temperature control zone to a second rate value, where the first rate value is less than the second rate value. This means the cooling rate of the thin-walled optical zone is actively suppressed, while the thick-walled mounting structure zone cools at a faster rate. The controller adjusts the duty cycle of the active heating unit in the first temperature control zone to compensate for heat loss and adjusts the opening of the solenoid valve in the enhanced cooling circuit of the second temperature control zone to increase the cooling medium flow rate, thereby bringing the actual cooling rate of each zone closer to its respective target rate. Meanwhile, the controller continuously calculates the real-time temperature difference between the two cavity zones. When this difference decreases to a preset threshold, the control logic switches to the second stage, resetting the target cooling rates of the first and second temperature control zones to the same third rate value. Simultaneously, the heating unit and cooling circuit are adjusted to ensure both zones continue cooling at a consistent rate until the ejection temperature range is reached. Throughout this process, the controller's PID parameters are tuned in segments according to the different cooling stages to ensure a smooth transition during rate switching and avoid introducing new temperature fluctuations due to sudden control changes.
[0031] In some examples, the preset high temperature range is set according to the glass transition temperature of the injection molding material, and the lower limit of the preset high temperature range is higher than the glass transition temperature; the active thermal compensation maintains the cavity temperature of the first temperature control zone at no lower than the glass transition temperature throughout the cooling stage, until the cavity temperature of the second temperature control zone drops to the ejection temperature range.
[0032] In some examples, the buffer cooling circuit of the third temperature control zone adopts a gradually spaced conformal water channel, and the arrangement spacing of the gradually spaced conformal water channel is gradually adjusted from the first temperature control zone to the second temperature control zone to form a continuous and smooth temperature gradient; heat insulation structures are provided at the partition boundaries between the third temperature control zone and the first and second temperature control zones.
[0033] In one possible implementation, the third temperature control zone corresponds to the transition area between the first and second temperature control zones on the mold cavity where the wall thickness gradually changes. Its buffer cooling circuit adopts a through-type water channel that conforms to the curved surface of the cavity in the transition area. The distance from the water channel to the cavity surface remains constant throughout. The center spacing of the water channel gradually narrows linearly from the end closer to the first temperature control zone to the end closer to the second temperature control zone. Through the linear transition of cooling intensity, a continuous and smooth temperature gradient is formed in the two core temperature control zones. At the boundary between the third temperature control zone and the first and second temperature control zones, a closed blind hole array is machined along the boundary and continuously staggered. The blind holes are filled with a low thermal conductivity insulating medium to form a thermal resistance barrier, blocking the thermal conduction crosstalk between adjacent temperature control zones and ensuring the independence and stability of the temperature control of each zone.
[0034] In some examples, step S3 includes: Within each temperature control zone, the surface temperature near the cavity surface and the deep temperature near the cooling circuit or heating unit are collected respectively; the control target includes: the surface temperature difference converges to a first preset threshold, and the deep temperature difference converges to a second preset threshold.
[0035] In some examples, step S3 further includes: Temperature control is achieved by using a closed-loop regulation algorithm. During the regulation process, the cavity temperature in the first temperature control zone is always kept no lower than that in the second temperature control zone. Simultaneously, cross-zone temperature distribution data of the mold substrate is collected. Based on the pre-constructed heat conduction model of the mold substrate, feedforward compensation correction is performed on the heating power of the active heating unit and the cooling medium flow rate of the enhanced cooling circuit to offset the temperature fluctuations caused by heat conduction crosstalk between the two temperature control zones.
[0036] In some examples, before the cooling stage, there are also a filling stage and a holding stage: the filling stage controls the cavity temperature of both the first and second temperature control zones to rise to a temperature that matches the preset high temperature range of the first temperature control zone; the holding stage maintains the cavity temperature of the first temperature control zone stable and gradually cools the cavity temperature of the second temperature control zone; before the end of the holding stage, the freezing state of the cavity gate is monitored in real time, and when the gate reaches the critical freezing state, the pre-enhanced cooling of the second temperature control zone is started in advance, while maintaining the thermal compensation state of the first temperature control zone, so as to achieve a seamless connection between the end of the holding stage and the core control of the cooling stage.
[0037] The above are merely preferred embodiments of this application. The scope of protection of this application is not limited to the above embodiments. Any equivalent modifications or changes made by those skilled in the art based on the content disclosed in this application should be included within the scope of protection recorded in the claims.
Claims
1. A method for differentiated cooling of automotive lamp cover molds, wherein the automotive lamp cover plastic part includes a thin-walled optical functional area and a thick-walled mounting structure area, characterized in that... The method includes: S1: The mold cavity is divided into a first temperature control zone and a second temperature control zone. The first temperature control zone corresponds to the thin-walled optical functional zone, and the second temperature control zone corresponds to the thick-walled mounting structure zone. The first temperature control zone is equipped with an active heating unit and a cooling circuit, and the second temperature control zone is equipped with an enhanced cooling circuit. S2: During the cooling stage, active thermal compensation is implemented in the first temperature control zone to maintain the cavity temperature of the first temperature control zone within a preset high temperature range; at the same time, enhanced cooling is implemented in the second temperature control zone to rapidly cool down the second temperature control zone. S3: Real-time acquisition of the actual cavity temperature of the first temperature control zone and the second temperature control zone, with the goal of the cavity temperature difference between the first temperature control zone and the second temperature control zone converging to within a preset threshold, and adjustment of the heating power of the active heating unit and the cooling medium flow rate of the enhanced cooling circuit; S4: When the cavity temperatures of the first temperature control zone and the second temperature control zone both reach the ejection temperature range of the plastic part, stop active thermal compensation and enhanced cooling, and open the mold for ejection.
2. The method according to claim 1, characterized in that, The mold cavity also includes a third temperature control zone, which is located between the first temperature control zone and the second temperature control zone and is equipped with a buffer cooling circuit. During the cooling stage, the third temperature control zone is subjected to medium flow cooling to buffer the temperature gradient between the first temperature control zone and the second temperature control zone.
3. The method according to claim 1, characterized in that, The control objectives include: In the initial stage of cooling, the cavity temperatures of the first temperature control zone and the second temperature control zone are reduced synchronously, and the temperature reduction rate of the first temperature control zone is less than that of the second temperature control zone; when the cavity temperature difference is less than a preset threshold, the temperature reduction rate of the first temperature control zone is controlled to be consistent with that of the second temperature control zone.
4. The method according to claim 1, characterized in that, The preset high temperature range is set according to the glass transition temperature of the injection molding material, and the lower limit of the preset high temperature range is higher than the glass transition temperature; the active thermal compensation maintains the cavity temperature of the first temperature control zone at no lower than the glass transition temperature throughout the cooling stage, until the cavity temperature of the second temperature control zone drops to the ejection temperature range.
5. The method according to claim 2, characterized in that, The buffer cooling circuit of the third temperature control zone adopts a gradually spaced conformal water channel. The arrangement spacing of the gradually spaced conformal water channel is gradually adjusted from the first temperature control zone to the second temperature control zone to form a continuous and smooth temperature gradient. The partition boundaries between the third temperature control zone and the first and second temperature control zones are all provided with heat insulation structures.
6. The method according to claim 1, characterized in that, Step S3 includes: Within each temperature control zone, the surface temperature near the cavity surface and the deep temperature near the cooling circuit or heating unit are collected respectively; the control target includes: the surface temperature difference converges to a first preset threshold, and the deep temperature difference converges to a second preset threshold.
7. The method according to claim 1, characterized in that, Step S3 further includes: Temperature control is achieved by using a closed-loop regulation algorithm. During the regulation process, the cavity temperature in the first temperature control zone is always kept no lower than that in the second temperature control zone. Simultaneously, cross-zone temperature distribution data of the mold substrate is collected. Based on the pre-constructed heat conduction model of the mold substrate, feedforward compensation correction is performed on the heating power of the active heating unit and the cooling medium flow rate of the enhanced cooling circuit to offset the temperature fluctuations caused by heat conduction crosstalk between the two temperature control zones.
8. The method according to claim 1, characterized in that, Before the cooling stage, there are also a mold filling stage and a pressure holding stage: the mold filling stage controls the cavity temperature of both the first and second temperature control zones to rise to a temperature that matches the preset high temperature range of the first temperature control zone; the pressure holding stage maintains the cavity temperature of the first temperature control zone stable and gradually cools the cavity temperature of the second temperature control zone; before the end of the pressure holding stage, the freezing state of the cavity gate is monitored in real time. When the gate reaches the critical freezing state, the pre-enhanced cooling of the second temperature control zone is started in advance, while maintaining the thermal compensation state of the first temperature control zone, so as to achieve a seamless connection between the end of the pressure holding stage and the core control of the cooling stage.