Built-in gradient cooling die-casting mold

Abstract

This invention provides a built-in gradient cooling die-casting mold, belonging to the field of metal die-casting technology. The mold includes a mold base, an upper mold, at least two sets of cooling modules, a temperature detection unit, a cooling medium supply module, a mold opening drive assembly, a demolding ejection assembly, and a control system. Multiple cooling modules are arranged sequentially along the flow direction of the molten metal from the center of the cavity to both ends. Each cooling module has a different thermal conductivity, which can form a preset temperature gradient around the cavity. The temperature detection unit acquires the temperature of each cooling section in real time, and the control system independently adjusts the cooling medium flow rate and / or temperature of each cooling section based on the temperature signal. This invention achieves directional solidification of the molten metal from the far end to the near end through the synergistic effect of thermal conductivity differences and dynamic flow rate control, ensuring unobstructed feeding channels, significantly reducing shrinkage cavities and porosity defects, and possessing adaptive adjustment capabilities, making it suitable for the precision forming of complex structure die-cast parts.

Description

Technical Field

[0001] This invention relates to the field of metal die casting technology, and in particular to a die casting mold with built-in gradient cooling. Background Technology

[0002] Die casting molds are core equipment in the metal pressure casting process, widely used in the mass production of non-ferrous alloy parts such as aluminum alloys and zinc alloys in the automotive, communications, electronics, and aerospace industries. Their basic working principle is as follows: molten metal is rapidly filled into the cavity formed by the mold base and upper mold after they are closed under high pressure, and then rapidly cooled and solidified under pressure holding conditions. The mold is then opened, and the finished product is removed by the ejection mechanism.

[0003] In existing die-casting molds, several independent and identical cooling channels are typically set inside the mold base. These channels are arranged parallel to each other below the cavity and supplied with cooling water at the same temperature through a common cooling pipe. This uniform cooling method has significant technical drawbacks: First, because castings often have thick and thin-walled areas, the thick areas accumulate more heat and dissipate it more slowly during cooling, while the thin-walled areas dissipate heat more quickly. If a uniform cooling intensity is used, the thin-walled areas are prone to premature solidification, closing the feeding channels. This results in the thick areas not receiving molten metal replenishment during subsequent shrinkage, leading to internal defects such as shrinkage cavities and porosity, severely affecting the density and mechanical properties of the casting. Second, existing molds lack real-time feedback and independent adjustment capabilities for the temperature of different areas of the cavity. When process parameters fluctuate or the ambient temperature changes, the cooling rate of each part cannot be dynamically adjusted, resulting in poor product dimensional stability, high scrap rates, and the need for frequent mold trials and repairs, increasing production cycles and costs. Summary of the Invention

[0004] The purpose of this invention is to provide a die-casting mold with built-in gradient cooling to solve the technical problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A die-casting mold with built-in gradient cooling, comprising:

[0007] The mold base has a cavity on its upper surface;

[0008] The upper mold has a molded shape on its lower surface that is adapted to the cavity. When the upper mold and the mold base are closed, the cavity and the molded shape together form a molding space for molding the product.

[0009] A cooling module is embedded inside the mold base. There are at least two sets of cooling modules, which are arranged sequentially along the flow direction of the molten metal from the center of the cavity to both ends, so as to divide the cavity into multiple cooling sections. The cooling modules corresponding to each cooling section have different thermal conductivity, so as to form a preset temperature gradient distribution around the cavity in the mold base.

[0010] A temperature detection unit is installed inside the mold base to acquire temperature signals of different cooling zones around the cavity in real time.

[0011] A cooling medium supply module is independently connected to each of the cooling modules and is used to independently supply cooling medium to each of the cooling sections.

[0012] A mold opening drive assembly is used to drive the upper mold to move away from or closer to the mold base;

[0013] A demolding ejection assembly is disposed inside the mold base, with one end extending into the cavity, and configured to eject the die-cast product from the cavity by vertical movement; and

[0014] The control system is signal-connected to the temperature detection unit and the cooling medium supply module, and is used to adjust the flow rate and / or temperature of the cooling medium supplied to each of the cooling sections according to the temperature signal, so as to control the molten metal to solidify in the order from the far end to the near end.

[0015] Based on the above technical solutions, the present invention also provides the following optional technical solutions:

[0016] In one alternative: the mold base is provided with a cooling cavity for housing the cooling module and a supply cavity for installing the cooling medium supply module inside the cavity. The two sets of cooling modules are distributed at equal intervals from the center of the cooling cavity to both ends, and the upper surface of the cooling module is in contact with the outer wall of the cavity.

[0017] In one alternative embodiment: the cooling module includes a module base and a high thermal conductivity bushing layer, which can be fastened together. One end of the module base has an external connector, and semi-medium channels are formed on the upper surface of the module base and the lower surface of the high thermal conductivity bushing layer. After the module base and the high thermal conductivity bushing layer are fastened together, a cooling pipe is formed. Both ends of the cooling pipe pass through the external connector and are connected to the cooling medium supply module through a medium external pipe.

[0018] In one alternative: the external connector has an internal socket and the end of the high thermal conductivity bushing layer has a plug that can be inserted into the socket.

[0019] In one alternative: the cooling cavity is provided with multiple mounting channels, and the mounting channels are evenly distributed along the flow direction of the molten metal from the center to both ends. Each module base is provided with a plug-in block on its lower end face, and each plug-in block can slide into the corresponding mounting channel.

[0020] In one alternative, the tube density inside each of the cooling modules arranged along the flow direction of the molten metal from the center to both ends gradually increases.

[0021] In one alternative: the temperature detection unit includes multiple thermocouples arranged at intervals along the filling direction of the cavity, the multiple thermocouples being divided into multiple groups and corresponding to each cooling module.

[0022] In one alternative embodiment: the mold base has an ejection cavity near the bottom; the ejection assembly includes a mold opening drive assembly and an ejector pin unit; the ejector pin unit is located at the center of the mold base, with its top extending into the cavity and flush with the bottom wall of the cavity; the mold opening drive assembly includes an ejection drive frame, an ejection action unit, and at least one ejection cylinder; the ejection drive frame is movably installed inside the ejection cavity and has at least one mold opening ejector pin on it; the mold opening ejector pin passes through the mold base from a corner and connects to the upper mold; the ejection action unit is located on the ejection drive frame and is used to drive the ejector pin unit upwards.

[0023] In one alternative: an inclined drive rod is provided inside the ejection cavity, the ejection action unit includes a drive block and an inclined part of the drive block facing the ejector unit, an inclined through hole is provided in the middle of the drive block and the inclined drive rod slides through the inclined through hole, the side of the drive block is connected to the ejection drive frame and can move laterally along the ejection drive frame.

[0024] In one alternative: the cavity has a sealing groove at its center, the ejector unit includes an ejector post and an ejector plate, the ejector post penetrates the center of the mold base, its lower end extends into the ejection cavity, and is provided with a lower plate, the lower plate is connected to the top wall of the ejection cavity by a spring, the ejector plate is located at the top of the ejector post, and it is sealed and fitted together with the sealing groove.

[0025] By adopting the above technical solution, the present invention has the following beneficial effects:

[0026] This invention, by arranging multiple cooling modules with different thermal conductivity coefficients sequentially along the flow direction of the molten metal, and combining this with a control system to independently and dynamically adjust the flow rate and temperature of the cooling medium in each cooling section, can create and maintain a preset temperature gradient distribution around the mold cavity. This guides the molten metal to solidify sequentially from the far end region away from the gate to the near end region closer to the gate. This solidification sequence ensures that the feeding channel remains open at all times, allowing thicker sections to receive continuous replenishment of molten metal from the far end during solidification and shrinkage. This effectively suppresses casting defects such as shrinkage cavities, porosity, and hot cracks, significantly improving the internal density and mechanical properties of the casting.

[0027] This invention integrates a temperature detection unit embedded inside the mold base, enabling real-time acquisition of actual temperature signals from each cooling zone. The control system uses this signal for closed-loop feedback, independently adjusting the cooling medium flow rate and / or temperature of each cooling zone. This dynamic adjustment mechanism automatically compensates for cavity temperature deviations caused by ambient temperature fluctuations, changes in cooling medium supply, or cumulative heat effects from continuous production, ensuring that the cooling rate of each zone remains within the optimal process window. This significantly improves batch-to-batch product dimensional consistency and yield, reducing reliance on manual parameter adjustments based on experience. Attached Figure Description

[0028] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the overall structure of a built-in gradient cooling die-casting mold according to the present invention.

[0030] Figure 2 This is a schematic diagram of the axial structure of the mold base in this invention.

[0031] Figure 3 This is a schematic diagram of the mold base structure in this invention.

[0032] Figure 4 This is a schematic diagram of the cooling module layout structure in this invention.

[0033] Figure 5 This is a schematic diagram of the cooling module structure in this invention.

[0034] Figure 6 This is a schematic diagram of the module base structure in this invention.

[0035] Figure 7 This is a schematic diagram of the high thermal conductivity bushing layer structure in this invention.

[0036] Figure 8 This is a schematic diagram of the demolding and ejection assembly structure in this invention.

[0037] Figure reference numerals: Mold base 100, cooling cavity 110, ejection cavity 120, sealing groove 130, mounting channel 140, angled drive rod 150, supply cavity 160, upper mold 200, ejector pin unit 300, ejector pillar 310, ejection plate 320, lower plate 330, ball bearing 340, spring 350, cooling module 400, module base 410, semi-medium channel 411, insertion hole 412, external connector 413, high thermal conductivity bushing layer 420, insertion pillar 421, insertion block 430, mold opening drive assembly 500, ejection drive frame 510, mold opening ejector pillar 520, ejection cylinder 530, drive block 540, angled through hole 550, angled surface 560, cooling medium supply module 600, external medium pipe 610. Detailed Implementation

[0038] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] The left, right, up, and down positions of the various components shown in the attached diagram are just one arrangement method; the specific positions should be set according to specific needs.

[0040] In one embodiment, such as Figures 1-4As shown, a die-casting mold with built-in gradient cooling includes a mold base 100, an upper mold 200, a cooling module 400, a demolding ejection assembly, and a temperature detection unit. The upper surface of the mold base 100 has a cavity, and the lower surface of the upper mold 200 has a mold shape adapted to the cavity. The cooling module 400 is embedded inside the mold base 100 and there are at least two sets. The two sets of cooling modules 400 are arranged sequentially along the flow direction of the molten metal from the center to both ends to form multiple cooling sections. Each cooling section has a different thermal conductivity, so that a preset temperature gradient distribution is formed around the cavity in the mold base 100. The temperature detection unit is located in the mold base 100. Inside the mold base 100, temperature signals of different cooling zones around the cavity are acquired in real time; the cooling medium supply module 600 is connected to the cooling module 400 and is used to independently supply cooling medium to each cooling zone; it also includes a control system and a demolding ejection assembly. The control system is signal-connected to the temperature detection unit and the cooling medium supply module 600 and is used to adjust the flow rate and / or temperature of the cooling medium supplied to each cooling zone according to the temperature signal; the demolding ejection assembly is located inside the mold base 100, with one end extending into the cavity, and ejects the die-cast product from the cavity by vertical movement.

[0041] In this embodiment of the invention, after the mold base 100 and the upper mold 200 are closed, the cavity and mold cooperate to form a molding space. Molten metal is introduced into the molding space by an external injection system, flowing from the center of the cavity to both ends and passing through various cooling sections. During the cooling process, the cooling medium supply module 600 circulates and injects cooling medium into each cooling module 400. The cooling medium exchanges heat with the outer wall of the cavity to cool and solidify the molten metal. Because each cooling section has a different thermal conductivity and the control system controls the flow rate of the cooling medium within the cooling module 400, differentiated cooling intensities can be provided for different areas of the casting (e.g., thicker parts require slow cooling, while thinner, farther ends require rapid cooling), thus guiding the molten metal to solidify in the order of "far end → near end," ensuring unobstructed feeding channels. After the product is formed, the mold base 100 and the upper mold 200 move away from each other. The demolding ejection component operates and acts on the product, subjecting it to an upward thrust, causing the product to be quickly demolded from the cavity.

[0042] In one embodiment, such as Figures 1-7 As shown, the mold base 100 has a cooling cavity 110 for housing the cooling module 400 and a supply cavity 160 for installing the cooling medium supply module 600 inside the cavity. The two sets of cooling modules 400 are distributed at equal intervals from the center of the cooling cavity 110 to both ends. The upper surface of the cooling module 400 is in contact with the outer wall of the cavity to achieve heat conduction.

[0043] The cooling module 400 includes a module base 410 and a high thermal conductivity bushing layer 420. The module base 410 and the high thermal conductivity bushing layer 420 can be fastened together. One end of the module base 410 has an external connector 413, and semi-medium channels 411 are formed on both the upper surface of the module base 410 and the lower surface of the high thermal conductivity bushing layer 420. After the module base 410 and the high thermal conductivity bushing layer 420 are fastened together, a cooling pipe is formed. Both ends of the cooling pipe pass through the external connector 413 and are connected to the cooling medium supply module 600 through a medium external pipe 610. In this embodiment of the invention, the high thermal conductivity bushing layer 420 is made of materials with a thermal conductivity ≥300. The high thermal conductivity bushing 420 is made of copper alloy material with a thermal conductivity of ≤2 W / m·K and is closely attached to the outer wall of the cavity. It is responsible for quickly dissipating heat from the cavity surface. The high thermal conductivity bushing 420 and the module base 410 are detachable. Therefore, when the cooling pipe is blocked, each cooling module 400 can operate independently and can be pulled out from the cooling cavity 110 to solve the blockage problem of the cooling pipe individually. After the module base 410 and the high thermal conductivity bushing 420 are released from their latching state, the cooling pipe is divided into two semi-medium channels 411 located on the upper surface and the lower surface of the high thermal conductivity bushing 420, respectively. The semi-medium channels 411 are exposed on the outside, which facilitates the cleaning of impurities in the cooling pipe. The module base 410 is made of ceramic material with a thermal conductivity of ≤2 W / m·K. The external connector 413 has an insertion hole 412 inside, and the end of the high thermal conductivity bushing layer 420 has a plug post 421 that can be inserted into the insertion hole 412 to achieve a precise fit between the module base 410 and the high thermal conductivity bushing layer 420. The module base 410 and the high thermal conductivity bushing layer 420 have a heat insulation layer on their sides, which covers the surfaces of the module base 410 and the high thermal conductivity bushing layer 420 to reduce heat loss.

[0044] In one embodiment, such as Figures 1-7 As shown, the cooling cavity 110 has multiple mounting channels 140 arranged inside, and the mounting channels 140 are evenly distributed along the flow direction of the molten metal from the center to both ends. Each module base 410 has a plug-in block 430 on its lower end face, and each plug-in block 430 can slide into the corresponding mounting channel 140. In this embodiment of the invention, each module base 410 can be introduced into the cooling cavity 110 from its port, and the plug-in block 430 is correspondingly inserted into the mounting channel 140 to ensure the stable installation of the cooling module 400 inside the cooling cavity 110. The tube density inside each cooling module 400 arranged along the flow direction of the molten metal from the center to both ends gradually increases. A denser tube arrangement provides stronger local cooling; a sparser tube arrangement provides a relatively mild cooling intensity. The differentiated design of tube diameter and tube density is a reliable physical basis for achieving gradient cooling.

[0045] In one embodiment, such as Figures 1-7As shown, the temperature detection unit includes multiple thermocouples arranged at intervals along the filling direction of the cavity. These thermocouples are divided into multiple groups and correspond to each cooling module 400. In this embodiment, the control unit is signal-connected to the temperature detection unit and the cooling medium supply module 600, and is used to adjust the flow rate and / or temperature of the cooling medium supplied to each cooling section according to the temperature signal. The control unit may further include a data acquisition module, a storage module (pre-stores target temperature gradient distribution data), a comparison module (generates deviation signals), and a control signal output module.

[0046] In one embodiment, such as Figures 1-7 As shown, the mold base 100 has an ejection cavity 120 near the bottom. The ejection assembly includes a mold opening drive assembly 500 and an ejector pin unit 300. The ejector pin unit 300 is located at the center of the mold base 100, with its top extending into the cavity and flush with the bottom wall of the cavity. The mold opening drive assembly 500 includes an ejection drive frame 510, an ejection action unit, and at least one ejection cylinder 530. The ejection drive frame 510 is movably mounted inside the ejection cavity 120 and has at least one mold opening ejector pin 520 on it. The mold opening ejector pin 520 penetrates the mold base 100 from a corner and connects to the upper... Mold 200; The ejection unit is mounted on the ejection drive frame 510 and is used to drive the ejector pin unit 300 upward; In this embodiment of the invention, the ejection cylinder 530 works and drives the ejection drive frame 510 to move vertically. The ejection unit and the mold opening ejector pin 520 both move upward with the ejection drive frame 510. In the initial stage, the mold opening ejector pin 520 drives the upper mold 200 to move upward, so as to realize the mold opening of the upper mold 200 and the mold base 100. After the mold opening is completed, the ejection unit acts on the bottom of the ejector pin unit 300 to push the ejector pin unit 300 to move upward, and the product is separated from the cavity to achieve rapid demolding.

[0047] In one embodiment, such as Figures 1-8As shown, the ejection cavity 120 is provided with an inclined drive rod 150. The ejection unit includes a drive block 540 and an inclined portion 560 disposed on the drive block 540 facing the ejector pin unit 300. An inclined through hole 550 is provided in the middle of the drive block 540, and the inclined drive rod 150 slides through the inclined through hole 550. The side of the drive block 540 is connected to the ejection drive frame 510 and can move laterally along the ejection drive frame 510. In this embodiment of the invention, during mold opening and demolding, the ejection cylinder 530 drives the ejection drive frame. 510 moves upward, the mold opening ejector pin 520 and the drive block 540 both move upward, and the upper mold 200 moves upward to achieve mold opening; under the guidance of the inclined drive rod 150, the drive block 540 moves toward the ejector pin unit 300. After a space is formed between the upper mold 200 and the mold base 100, the inclined surface 560 gradually contacts the bottom of the ejector pin unit 300. As the drive block 540 moves, the inclined surface 560 acts upward on the ejector pin unit 300, causing the ejector pin unit 300 to move vertically, thereby lifting the product upward to complete demolding.

[0048] In one embodiment, such as Figures 1-8 As shown, the cavity has a sealing groove 130 at its center. The ejector unit 300 includes an ejector post 310 and an ejector plate 320. The ejector post 310 penetrates the center of the mold base 100, and its lower end extends into the ejection cavity 120. A lower plate 330 is provided thereon. The lower plate 330 is connected to the top wall of the ejection cavity 120 by a spring 350. The ejector plate 320 is located at the top of the ejector post 310 and is sealed and fitted together with the sealing groove 130. In this embodiment of the invention, the bottom of the lower plate 330 has ball bearings, which are connected to the inclined surface. After the 560-degree rolling contact occurs, the drive block 540 moves towards the ejector unit 300 and contacts the ball bearing 340. The inclined surface 560 then pushes the ejector pin 310 upwards. The ejector plate 320 follows the ejector pin 310 upwards and, after disengaging from the sealing groove 130, lifts the product. When the ejector cylinder 530 drives the ejector drive frame 510 downwards, the drive block 540 moves away from the ejector unit 300. Under the elastic force of the spring 350, the ejector pin 310 moves downwards, and the ejector plate 320 fits snugly into the sealing groove 130, ensuring a tight seal. The sealing groove 130 is a conical groove, and the ejector plate 320 is also conical in shape.

[0049] The above embodiment provides a die-casting mold with built-in gradient cooling, the working principle of which is as follows:

[0050] I. Mold Closing and Filling Stage

[0051] First, an external drive mechanism (not shown in the figure) drives the upper mold 200 downwards to close with the mold base 100. After closing, the cavity on the upper surface of the mold base 100 and the mold on the lower surface of the upper mold 200 precisely fit together to form a sealed molding space. Subsequently, an external liquid injection system introduces high-temperature molten metal into this molding space. During the filling process, the molten metal, starting from the center of the cavity, smoothly flows towards both ends of the cavity along a preset flow path, passing through various areas responsible for different cooling tasks.

[0052] II. Gradient Cooling and Sequential Solidification Stage

[0053] During the molten metal filling and cooling process, the control system (not shown in the figure) activates the cooling medium supply module 600 according to a preset program. The cooling medium (such as water or heat transfer oil) is independently delivered to at least two sets of cooling modules 400 embedded inside the mold base 100 via the external medium pipe 610.

[0054] Each cooling module 400 is formed by the snap-fitting of a module base 410 and a high thermal conductivity bushing layer 420, creating a complete cooling pipe inside. The cooling medium circulates within the pipe and efficiently absorbs heat from the cavity wall through the high thermal conductivity bushing layer 420 (made of copper alloy material with a thermal conductivity ≥300 W / m·K), which is in close contact with the outer wall of the cavity, thus achieving rapid cooling of the corresponding section of molten metal.

[0055] During this process, since the cooling modules 400 are evenly distributed along the direction of molten metal flow (from the center to both ends) within the cooling cavity 110, and the density of the internal tubes gradually increases, and the module base 410 is constructed with a ceramic material with a thermal conductivity ≤2 W / m·K to form a heat-insulating base, each cooling section along the filling direction has a different equivalent thermal conductivity. In conjunction with the dynamic adjustment of the control system, specifically: the temperature detection unit (i.e., multiple sets of thermocouples spaced apart along the filling direction of the cavity) acquires the temperature signal of each cooling section in real time and feeds it back to the control system. The control system compares the measured temperature with the internally stored target temperature gradient distribution data, generates a deviation signal, and then adjusts the flow rate and / or temperature of the cooling medium supplied to each cooling section through control signals.

[0056] The coupling effect of the aforementioned physical structure and intelligent control creates a preset, non-uniform temperature gradient distribution around the mold base 100 within the cavity. Specifically, the distal region (thin-walled areas) near the end of the molten metal flow experiences high cooling intensity and rapid temperature drop, while the proximal region (thick areas or gates) near the center experiences relatively moderate cooling intensity and slow temperature drop. This strategy effectively guides the molten metal to solidify strictly in the "far end → proximal end" sequence, ensuring that the casting always receives molten metal from the gate or the thick central region for feeding during shrinkage, thereby significantly reducing casting defects such as shrinkage cavities and porosity.

[0057] III. Mold Opening and Ejection / Demolding Stage

[0058] After the casting has cooled and solidified in the mold, the control system issues a command to start the demolding procedure. First, the ejector cylinder 530 in the mold opening drive assembly 500 starts working, driving the ejector drive frame 510 to move vertically upward inside the ejector cavity 120. The mold opening ejector pin 520, fixed on the ejector drive frame 510, moves upward synchronously, its top end penetrating the mold base 100 from the corner and pushing the upper mold 200, causing the upper mold 200 to separate from the mold base 100, thus completing the mold opening action.

[0059] As the ejector drive frame 510 continues to move upward, the drive block 540 mounted on it also rises accordingly. Since the drive block 540 has a slanted through hole 550 in its center, and a slanted drive rod 150 is fixedly mounted inside the ejector cavity 120, passing through the slanted through hole 550, under the guidance of the slanted drive rod 150, the drive block 540, while rising, will also move laterally horizontally along the ejector drive frame 510 towards the ejector pin unit 300.

[0060] When the drive block 540 moves towards the ejector unit 300 to a certain position, its inclined surface 560 begins to roll into contact with the ball bearing 340 at the lower end of the ejector unit 300. As the drive block 540 continues to move laterally, the inclined surface of the inclined surface 560 generates an upward component force, which pushes the lower plate 330 against the tension of the spring 350 through the ball bearing 340, causing the ejector pin 310 to slide vertically upward at the center of the mold base 100. The ejector plate 320 fixed to the top of the ejector pin 310 then disengages from the sealing groove 130 at the bottom of the cavity and rises upward, thereby smoothly ejecting the formed casting from the cavity and achieving rapid demolding.

[0061] IV. Reset Phase

[0062] After the casting is removed, the ejector cylinder 530 drives the ejector drive frame 510 to move downwards and reset. During this process, the drive block 540 slides laterally in the opposite direction (i.e., away from the ejector pin unit 300) under the action of the inclined drive rod 150, and the inclined part 560 disengages from the ball bearing 340. At this time, under the elastic restoring force of the spring 350, the ejector pin unit 300 drives the ejector column 310 and the ejector plate 320 to move downwards until the ejector plate 320 is precisely re-engaged in the sealing groove 130 and completely flush with the bottom wall of the cavity, ensuring the flatness and sealing of the bottom surface of the cavity, and preparing for the next die-casting cycle.

[0063] Meanwhile, the cooling medium supply module 600 stops or switches to standby mode, awaiting instructions for the next cycle. The entire workflow, through closed-loop regulation of the control system and coordinated action of the mechanical mechanisms, achieves efficient and high-quality die-casting production with gradient cooling.

[0064] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

Claims

1. A die-casting mold with built-in gradient cooling, characterized in that, include: The mold base has a cavity on its upper surface; The upper mold has a molded shape on its lower surface that is adapted to the cavity. When the upper mold and the mold base are closed, the cavity and the molded shape together form a molding space for molding the product. A cooling module is embedded inside the mold base. There are at least two sets of cooling modules, which are arranged sequentially along the flow direction of the molten metal from the center of the cavity to both ends, so as to divide the cavity into multiple cooling sections. The cooling modules corresponding to each cooling section have different thermal conductivity, so as to form a preset temperature gradient distribution around the cavity in the mold base. A temperature detection unit is installed inside the mold base to acquire temperature signals of different cooling zones around the cavity in real time. A cooling medium supply module is independently connected to each of the cooling modules and is used to independently supply cooling medium to each of the cooling sections. A mold opening drive assembly is used to drive the upper mold to move away from or closer to the mold base; A demolding ejection assembly is disposed inside the mold base, and one end of the demolding ejection assembly extends into the cavity, and is configured to eject the die-cast product from the cavity by vertical movement; as well as The control system is signal-connected to the temperature detection unit and the cooling medium supply module, and is used to adjust the flow rate and / or temperature of the cooling medium supplied to each of the cooling sections according to the temperature signal, so as to control the molten metal to solidify in the order from the far end to the near end.

2. The built-in gradient cooling die-casting mold according to claim 1, characterized in that, The mold base has a cooling cavity for housing the cooling module and a supply cavity for installing the cooling medium supply module inside the cavity. The two sets of cooling modules are distributed at equal intervals from the center of the cooling cavity to both ends, and the upper surface of the cooling module is in contact with the outer wall of the cavity.

3. The built-in gradient cooling die-casting mold according to claim 2, characterized in that, The cooling module includes a module base and a high thermal conductivity bushing layer; The module base and the high thermal conductivity bushing can be fastened together. One end of the module base has an external connector, and the upper surface of the module base and the lower surface of the high thermal conductivity bushing are both provided with semi-medium channels. After the module base and the high thermal conductivity bushing are fastened together, a cooling pipe is formed. The two ends of the cooling pipe pass through the external connector and are connected to the cooling medium supply module through the external medium pipe.

4. The built-in gradient cooling die-casting mold according to claim 3, characterized in that, The external connector has an internal socket and the end of the high thermal conductivity bushing layer has a plug that can be inserted into the socket.

5. The built-in gradient cooling die-casting mold according to claim 3, characterized in that, The cooling cavity is provided with multiple mounting channels, which are evenly distributed along the flow direction of the molten metal from the center to both ends. Each module base has a plug-in block on its lower end face, and each plug-in block can slide into the corresponding mounting channel.

6. The built-in gradient cooling die-casting mold according to claim 5, characterized in that, The density of the pipes inside each cooling module, arranged along the flow direction of the molten metal from the center to both ends, gradually increases.

7. The built-in gradient cooling die-casting mold according to claim 1, characterized in that, The temperature detection unit includes multiple thermocouples arranged at intervals along the filling direction of the cavity. The multiple thermocouples are divided into multiple groups and correspond to each cooling module.

8. The built-in gradient cooling die-casting mold according to claim 1, characterized in that, The mold base has an ejection cavity near the bottom, and the demolding ejection assembly includes a mold opening drive assembly and an ejector pin unit; The ejector pin unit is located at the center of the mold base, with its top extending into the cavity and flush with the bottom wall of the cavity. The mold opening drive assembly includes an ejection drive frame, an ejection action unit, and at least one ejection cylinder. The ejector drive frame is movably installed inside the ejector cavity, and at least one mold opening ejector pin is provided on it. The mold opening ejector pin passes through the mold base from the corner and is connected to the upper mold. The ejector action unit is provided on the ejector drive frame and is used to drive the ejector pin unit upward.

9. The built-in gradient cooling die-casting mold according to claim 8, characterized in that, The ejection cavity is provided with an inclined drive rod. The ejection action unit includes a drive block and an inclined part of the drive block facing the ejector unit. An inclined through hole is opened in the middle of the drive block and the inclined drive rod slides through the inclined through hole. The side of the drive block is connected to the ejection drive frame and can move laterally along the ejection drive frame.

10. The built-in gradient cooling die-casting mold according to claim 9, characterized in that, The cavity has a sealing groove in the center, and the ejector pin unit includes an ejector pin and an ejector plate; The top post penetrates the center of the mold base, and its lower end extends into the ejection cavity. A lower plate is provided thereon. The lower plate is connected to the top wall of the ejection cavity by a spring. The ejection plate is located at the top of the top post and is sealed together with the sealing groove.

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