CN-122008459-A - Mould subregion temperature control system based on adjustable thermal resistance boundary of air film

Abstract

The invention discloses a mold partition temperature control system based on an air film adjustable thermal resistance boundary, and belongs to the technical field of mold temperature control and thermal management. The system comprises a die body, at least two temperature control partitions and an air film adjustable thermal resistance boundary unit arranged between the adjacent temperature control partitions. The air film adjustable thermal resistance boundary unit comprises a boundary air cavity, an air injection micropore, an exhaust adjusting structure and an air supply unit. The gas enters the zone boundary area through the gas injection micropores and forms a gas film layer, and the thickness, the continuity, the stability and the coverage range of the gas film layer are changed by adjusting the gas supply pressure, the gas supply flow and the gas exhaust resistance, so that the thermal coupling strength between adjacent temperature control zones is adjusted. The system is suitable for injection molding, die casting, hot pressing and composite material forming dies.

Inventors

• SUN XIANPING
• Lu Kailun
• GAO SONG
• LI QIHAN
• Li Ruchuang
• WANG GUOSHENG

Assignees

• 长春工业大学

Dates

Publication Date

20260512

Application Date

20260413

Claims (6)

1. 1. A temperature control system for a mold partition based on an air film adjustable thermal resistance boundary is characterized by comprising a mold body (100), wherein the mold body (100) comprises a molding working part (110) and a mold body supporting part (120), at least two temperature control partitions (200) are correspondingly arranged in different areas of the molding working part (110), each temperature control partition (200) is respectively provided with an independent heating unit (410) and/or a cooling unit (420), an air film adjustable thermal resistance boundary unit (300) is arranged between adjacent temperature control partitions (200), the air film adjustable thermal resistance boundary unit (300) comprises a boundary air cavity (310) arranged along a partition boundary (230) and buried in the molding working part (110), a plurality of air injection micropores (320) communicated with the boundary air cavity (310) and arranged towards the adjacent area of the partition boundary (230), an air supply unit (430) communicated with the partition boundary air cavity (230), wherein the air injection micropores (320) and the air injection boundary air film (340) are matched with the air film adjustable thermal resistance boundary unit (300) to form a pressure regulation boundary layer (340) between the air film and the air film adjustable thermal resistance boundary layer (340) through the air film adjustable thermal resistance boundary layer (340) and the air film adjustable thermal resistance boundary layer (340) between the adjacent partition boundary regions, the air supply flow and the air exhaust resistance change the thickness, the continuity, the stability and the coverage of the air film layer (340) so as to adjust the thermal coupling strength between the adjacent temperature control subareas (200).
2. 2. The gas film adjustable thermal resistance boundary based mold zone temperature control system of claim 1, wherein the boundary gas cavity (310) is continuously arranged or intermittently arranged in segments along the zone boundary (230) to form a continuous gas film thermal resistance boundary or a segmented gas film thermal resistance boundary.
3. 3. The gas film adjustable thermal resistance boundary-based die zone temperature control system of claim 1, wherein the gas injection micropores (320) are arranged along a zone boundary (230) and have a pore diameter of 0.02 mm-1.00 mm, the distance between adjacent gas injection micropores (320) is 0.10 mm-5.00 mm, the arrangement depth of the boundary gas cavity (310) from a forming working surface is 0.5 mm-20 mm, the equivalent width of the boundary gas cavity (310) is 0.2 mm-10 mm, the equivalent height is 0.2 mm-8 mm, the gas supply pressure output to the boundary gas cavity (310) by the gas supply unit (430) is 0.01 MPa~0.80 MPa, the gas supply flow rate is 0.1L/min-50L/min, so that a continuous gas film layer (340) or a pulse layer (340) with a thickness of 0.01 mm-1.00 mm is formed in the zone boundary (230), and the gas exhaust adjusting structure (330) is a throttle, a throttle valve, a variable section exhaust channel or a combination thereof.
4. 4. The temperature control system for the mold partition based on the air film adjustable thermal resistance boundary of claim 1, wherein the air medium is air, nitrogen, argon or mixed gas thereof, the heating unit (410) and/or the cooling unit (420) of each temperature control partition (200) respectively form an independent thermal control loop, the temperature control system further comprises a control unit (400) and a temperature acquisition unit (500), the temperature acquisition unit (500) comprises partition temperature sensors (510) arranged inside each temperature control partition (200) and boundary temperature sensors (520) arranged near the partition boundary (230), and the control unit (400) is respectively connected with the air supply unit (430), the exhaust adjusting structure (330), the heating unit (410), the cooling unit (420) and the temperature acquisition unit (500).
5. 5. The system for controlling the temperature of the mold partition based on the air film adjustable thermal resistance boundary according to claim 4, wherein the control unit (400) is used for adjusting air supply pressure, air supply flow, air supply on-off state and air exhaust resistance according to temperature difference information between adjacent temperature control partitions (200) and temperature information of a partition boundary (230) area, and is used for adjusting heating intensity and/or cooling intensity of the corresponding temperature control partition (200) in parallel.
6. 6. The gas film adjustable thermal resistance boundary-based mold zone temperature control system of claim 1, wherein the division of the temperature control zone (200) is determined according to the wall thickness distribution, the gate position, the insert position, the apparent mass sensitive area or the defect sensitive area of a product, and the mold is an injection mold, a die casting mold, a hot pressing mold or a composite material molding mold.

Description

Mould subregion temperature control system based on adjustable thermal resistance boundary of air film Technical Field The invention relates to the technical field of mold temperature control and thermal management, in particular to a mold partition temperature control system which realizes partition thermal decoupling and adjustable boundary thermal resistance by constructing an air film adjustable thermal resistance boundary between adjacent temperature control partitions. Background In the molding process of injection molding, die casting, hot press molding, composite material compression molding and the like, the distribution of a mold temperature field directly influences melt flow behavior, filling uniformity, surface replicability, crystallization behavior, residual stress, dimensional stability and demolding quality. For the parts with obvious wall thickness difference, high local highlight requirement and reinforcing ribs, thin-wall areas, insert areas or defect sensitive areas, differential temperature control is usually required to be implemented on different areas of the die so as to meet the heat requirements of the different areas in the forming process. The existing mold temperature control technology generally adopts a mode of partition heating, partition cooling or a combination of the partition heating and the partition cooling to realize local temperature control. Although independent heat control loops can be respectively arranged in different areas, as the die matrix material generally has higher heat conductivity, obvious heat conduction still exists between adjacent temperature control subareas, so that the heat crosstalk is obvious, the subarea boundary is fuzzy, the temperature gradient is difficult to keep stable, and the subarea temperature control independence and the process response precision are further influenced. In order to reduce the thermal crosstalk, the prior art is also improved by increasing the density of cooling channels, optimizing the heating layout, forming heat insulation grooves or embedding heat insulation materials, and the like. However, most of the above methods belong to passive structural adjustment, the thermal resistance state of the thermal resistance state is basically fixed after the die is manufactured, and the thermal resistance state is difficult to dynamically adjust along with the change of the molding stage, and the differential requirements of different stages such as filling, pressure maintaining, shaping and cooling on the thermal coupling relation of the partition boundary cannot be considered. In addition, the existing technology related to gas participation heat exchange is mostly used for enhancing local heat exchange, auxiliary cooling or forming a heat insulation layer, but the boundary area between adjacent temperature control subareas is not used as an independent thermal resistance adjusting interface for structural design, and gas supply, gas exhaust, subarea temperature and temperature feedback are not integrated in a system, so that controllable adjustment of the thermal coupling strength between subareas is difficult to realize. Therefore, it is necessary to provide a new temperature control system for the mold partition, so that the boundary area between adjacent temperature control partitions is not only used as a geometric boundary, but is constructed as a functional interface with adjustable heat conduction characteristics, and the thermal coupling strength between the partitions is changed through air film formation and state adjustment, so that partition independence, boundary temperature gradient control capability and overall temperature control precision are improved. Disclosure of Invention Aiming at the problems that the thermal crosstalk between adjacent partitions is obvious, the thermal coupling strength is difficult to adjust, the thermal boundary resistance is fixed and the temperature control requirements of different process stages are difficult to adapt to in the existing temperature control technology of the mold partition, the invention provides a mold partition temperature control system based on an air film adjustable thermal boundary. The temperature control system for the mold partition based on the air film adjustable thermal resistance boundary comprises a mold body, at least two temperature control partitions and an air film adjustable thermal resistance boundary unit arranged between adjacent temperature control partitions, wherein the mold body comprises a forming working part and a mold body supporting part, the at least two temperature control partitions are correspondingly arranged in different areas of the forming working part, each temperature control partition is respectively provided with an independent heating unit and/or cooling unit, and the air film adjustable thermal resistance boundary unit comprises a boundary air cavity, a plurality of air injection micropores, an exhaust adjusting st