An embedded dense die casting process and mold structure

Abstract

The present invention discloses an embedded dense die-casting process and mold structure, and relates to the technical field of die-casting molds. An embedded dense die-casting mold includes a fixed mold, a movable mold, and a core layer molding mechanism, wherein the core layer molding mechanism includes an upper core mold group and a lower core mold group, the upper core mold group includes an upper column core and a dense core, and the lower core mold group includes a lower column core. Specifically, the upper column core, the dense core, and the lower column core cooperate with each other and are used to mold the inner wall of the die-casting, and the dense core is slidably sleeved on the circumference of the upper column core, and can perform secondary core filling when the pouring is completed. Furthermore, through the secondary core filling of the dense core, the molten metal can be effectively compressed in the molding cavity and flow to the low-pressure area, which is not only beneficial to improve the uniformity of the overall wall thickness of the die-casting, but also beneficial to meet the requirements of high density at the end of the casting or the thick-walled part of the die-casting.

Description

Technical Field

[0001] The invention relates to the technical field of die-casting dies, and in particular to an embedded dense die-casting process and a die structure. Background Art

[0002] The die-casting process is an indispensable part of modern manufacturing. It has been widely used in the production and manufacturing of complex-shaped parts in the fields of automobiles, electronics, aviation, etc., which improves the production efficiency of parts while also improving product quality. However, for some particularly important parts, such as oil pump housings, engine housings, wing connectors, etc., since such parts generally need to have higher comprehensive strength and thicker thickness, it is often difficult to achieve the internal density standard of the thick-walled area or end of the parts through traditional die-casting technology, which has a direct impact on the safety and service life of the product and poses certain safety hazards.

[0003] In response to the above technical problems, the industry currently generally adopts the method of increasing the cooling time or adding a vibration device inside the mold to improve the density of the workpiece. Although the former can ensure to a certain extent that the molten metal can be fully exhausted and solidified to form a good microstructure, it will undoubtedly extend the overall production die-casting cycle, thereby reducing the overall production efficiency. The latter uses high-frequency vibration to enable the molten metal to flow evenly and be fully exhausted, but it is found in application that due to the large space of the thick-walled area of ​​the cavity, a small number of keyholes, bubbles and other problems may still appear inside the thick-walled area at the end of the casting, and sometimes even cause new surface defects. Whether it is extending the solidification stage or introducing an additional vibration mechanism, it cannot fundamentally solve the problem, especially when encountering die-castings with more complex structures or higher density requirements, the traditional die-casting process seems to be more and more incapable. Summary of the invention

[0004] In order to improve the uniformity of the overall wall thickness of the die-casting, meet the requirement of high density at the casting end of the die-casting, and improve the die-casting process, the present application provides an embedded dense die-casting process and a mold structure.

[0005] In the first aspect, the embedded dense die-casting mold provided by the present application adopts the following technical solution:

[0006] An embedded dense die-casting mold, comprising:

[0007] A fixed die, the fixed die comprising a fixed die frame and a fixed die core, the fixed die core being provided with a fixed cavity surface for molding the outer side of the die casting;

[0008] A movable mold, the movable mold comprising a movable mold frame and a movable mold core, the movable mold core being provided with a movable cavity surface for molding the outer side of the die casting;

[0009] A core layer forming mechanism, the core layer forming mechanism comprises an upper core module and a lower core module, the upper core module and the lower core module are both embedded and fixed in the fixed mold frame, and are respectively located on both sides of the fixed mold core, the upper core module comprises an upper core pulling drive, an upper column core and a dense core, the lower core module comprises a lower core pulling drive and a lower column core, the upper core pulling drive is used to drive the upper column core and the dense core to slide back and forth toward the fixed mold core respectively, and the lower core pulling drive is used to drive the lower column core to slide back and forth toward the fixed mold core; the fixed mold cavity surface, the dynamic mold cavity surface, the upper column core, the dense core and the lower column core cooperate with each other to form a mold cavity;

[0010] Among them, the dense core is slidably sleeved on the circumference of the upper column core, and the dense core is used for secondary core filling when pouring is completed, and can cooperate with the upper column core and the lower column core to form the inner wall of the die casting.

[0011] By adopting the above technical scheme, the dense core is filled for the second time after the pouring is completed, so that the molten metal in the cavity can be continuously compressed and flow to the area with lower pressure, which can effectively make the pressure in each area reach a more ideal high pressure, and can fully fill and improve the gaps or voids in the thick-walled parts or the pouring end of the die-casting, which is beneficial to improve the uniformity of the overall wall thickness of the die-casting and meet the requirements of high density at the pouring end or thick-walled parts of the die-casting.

[0012] Optionally, a vibrating element is embedded in the upper column core.

[0013] By adopting the above technical solution, the upper column core is vibrated through the vibrator, which can also make the molten metal in the cavity flow evenly and be fully exhausted, which is beneficial to improving the uniformity of the overall wall thickness of the die casting and improving the density of the casting end or thick wall part of the die casting.

[0014] Optionally, the fixed mold frame is provided with a discharge barrel, and the movable mold core is provided with a flat side-cut runner. The discharge barrel, the runner and the cavity are interconnected. The runner corresponds to the outer wall of the circular column structure of the die-casting, and is poured in a straight line along the center tangent of the circular column structure of the die-casting.

[0015] By adopting the above technical scheme, a runner is set along the central tangent of the circular column structure, so that during pouring, the molten metal can flow along the annular periphery of the cavity on both sides and close together, which not only enables the molten metal to fully fill the cavity, thereby improving the wall thickness filling performance of the product perpendicular to the annular periphery, but also facilitates the exhaust in the cavity and improves the density of the thick wall parts of the die casting.

[0016] Optionally, the connection between the runner and the cavity and the intersection of the upper column core and the lower column core are staggered.

[0017] A connecting wedge is provided at one end of the upper column core facing the lower column core, and a connecting wedge groove corresponding to the connecting wedge is opened at the end of the lower column core. When the upper column core and the lower column core are attached to and pressed against each other, the connecting wedge is inserted into the connecting wedge groove.

[0018] By adopting the above technical solution, it is helpful to prevent the molten metal from having too much impact force on the upper column core and the lower column core when pouring, and to prevent the generation of obvious parting lines or flash on the inner side of the die casting. In addition, by providing a connecting wedge and a connecting inclined groove, the tightness of the upper column core and the lower column core when they are pressed together can be effectively improved, thereby further preventing the molten metal from penetrating between the upper column core and the lower column core.

[0019] Optionally, a plurality of overflow channels and overflow cavities are provided in the fixed mold core and the movable mold core, and the plurality of overflow cavities are interconnected with the mold cavity through the overflow channels. The movable mold core is provided with an exhaust groove, and the exhaust groove is connected with the overflow cavity.

[0020] Optionally, several groups of the overflow cavities are located on the outer peripheral side of the circular ring column structure of the corresponding die casting away from one end of the runner, and are evenly distributed along the center tangent of the circular ring column structure of the die casting; several groups of the overflow cavities are located on the outer peripheral side of the two end ports of the circular ring column structure of the corresponding die casting.

[0021] Optionally, the exhaust groove connects several groups of overflow chambers to each other.

[0022] By adopting the above technical solution, the compressed molten metal can flow to the low-pressure area, that is, it will flow along the overflow channel and overflow into the overflow cavity. At this time, not only the condensed slag in the initial pouring stage can be discharged, but also sufficient exhaust can be ensured, which can prevent exhaust difficulties caused by blockage.

[0023] Optionally, a pressure control module is provided at one end of the fixed mold frame away from the unloading barrel, a pressure control chamber is opened inside the pressure control module, the exhaust groove is connected with the pressure control chamber, the pressure control module is provided with a negative pressure tube and a pressure-stabilizing tube, and the negative pressure tube and the pressure-stabilizing tube are both connected with the pressure control chamber.

[0024] By adopting the above technical scheme, the air pressure in the cavity can be effectively adjusted, which is not only beneficial to fully discharge the gas in the cavity during the pouring process so that the molten metal can flow evenly, but also can maintain the internal pressure of the cavity stable in the subsequent pressure holding stage, which is beneficial to the cooling and molding of the die casting.

[0025] Optionally, a plurality of groups of temperature-controlling water channels are provided on the inner sides of the fixed mold core and the movable mold core, the temperature-controlling water channels are evenly distributed along the circular column structure of the die-casting, and the thinnest part at the end of the temperature-controlling water channel is provided at the thick-walled part of the corresponding die-casting.

[0026] By adopting the above technical solution, the problem of overcooling or overheating in some areas of the fixed mold core or the movable mold core can be effectively improved, which is conducive to the fixed mold core and the movable mold core to better shape the molten metal. In addition, by evenly distributing the temperature control water channel along the circumference of the circular column structure of the die casting, it is conducive to accurately controlling the molding of the thick wall part of the die casting and improving the molding efficiency and molding effect of the die casting.

[0027] In the second aspect, the embedded dense die-casting process provided by the present application adopts the following technical solution:

[0028] An embedded dense die-casting process comprises the following steps:

[0029] S1, mold closing: the movable mold and the fixed mold are closed to each other, the upper core-pulling driving member and the lower core-pulling driving member respectively drive the upper column core and the lower column core to close to each other, and form a larger molding cavity, and at the same time, the negative pressure tube is used to evacuate and reduce pressure to keep the pressure control cavity in a negative pressure state;

[0030] S2. Pouring: Pouring a certain amount of molten metal at low pressure, while introducing heat transfer liquid into the temperature-controlled water channel, and stopping the vacuum pipe from evacuating air when the molten metal fills the molding cavity;

[0031] S3, pressure-maintaining and densifying: when the molten metal fills the larger molding cavity, the vibrating member inside the upper column core is started, and the upper core-pulling driving member drives the dense core to advance into the molding cavity, compressing the molten metal in the molding cavity, and restoring the molding cavity to the target cavity size, and at the same time, the pressure-regulating tube is used to ventilate and pressurize the pressure-controlled cavity, keeping the pressure-controlled cavity in a pressurized state, and maintaining the pressure for a certain period of time;

[0032] S4, cooling: introducing cooling liquid into the temperature-controlled water channel;

[0033] S5, opening the mold and taking out the part: the movable mold and the fixed mold are separated from each other, and the upper core-pulling driving member and the lower core-pulling driving member respectively drive the upper column core, the dense core and the lower column core to slide out, so as to obtain a formed die-casting part.

[0034] By adopting the above technical solution, a die-casting with uniform wall thickness and high density at the pouring end and thick wall part can be produced.

[0035] In summary, the technical solution of this application has at least one of the following beneficial effects:

[0036] 1. By using a dense core to perform secondary core filling after pouring, the molten metal in the cavity is continuously compressed and flows to the area with lower pressure, which is beneficial to improve the uniformity of the overall wall thickness of the die casting and meet the requirements of high density at the end of the casting or the thick wall part of the die casting.

[0037] 2. By setting a vibrator in the pillar core, the vibrator makes the upper pillar core vibrate, which can make the molten metal in the cavity flow evenly and fully exhaust, which is beneficial to improve the uniformity of the overall wall thickness of the die casting and improve the density of the casting end or thick wall part of the die casting. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a structural schematic diagram of a die casting in the prior art.

[0039] Figure 2 It is a structural schematic diagram of an embedded dense die-casting mold in an embodiment of the present application.

[0040] Figure 3 It is a top view of an embedded dense die-casting mold in an embodiment of the present application.

[0041] Figure 4 yes Figure 3 Cross-sectional view of AA.

[0042] Figure 5 It is a structural schematic diagram of a fixed mold of an embedded dense die-casting mold in an embodiment of the present application.

[0043] Figure 6 It is a structural schematic diagram of a movable mold of an embedded dense die-casting mold in an embodiment of the present application.

[0044] Figure 7 It is a structural schematic diagram of an upper core module of an embedded dense die-casting mold in an embodiment of the present application.

[0045] Figure 8 It is a cross-sectional view of an upper core module of an embedded dense die-casting mold in an embodiment of the present application.

[0046] Fig. 9 It is a structural schematic diagram of a lower core module of an embedded dense die-casting mold in an embodiment of the present application.

[0047] Fig.10 It is a process flow chart of an embedded dense die-casting process in an embodiment of the present application.

[0048] Description of reference numerals:

[0049] 1. Die casting; 11. Upper column; 111. Thick wall area; 112. Thin wall area; 12. Lower column; 13. Connecting ear; 14. Upper column port; 15. Lower column port; 2. Fixed mold; 21. Fixed mold frame; 211. Lower barrel; 22. Fixed mold core; 3. Moving mold; 31. Moving mold frame; 32. Moving mold core; 321. Runner; 322. Exhaust groove; 4. Core layer molding mechanism; 41. Upper core mold group; 411. Upper core pull drive Parts; 412, upper column core; 4121, insulation layer; 4122, magnetic steel layer; 4123, eccentric rotor; 4124, connecting wedge platform; 413, dense core; 42, lower core module; 421, lower core driving part; 422, lower column core; 4221, connecting wedge groove; 5, cavity; 6, overflow channel; 7, overflow cavity; 8, pressure control module; 81, pressure control cavity; 82, negative pressure tube; 83, voltage regulator tube; 9, temperature control water channel. DETAILED DESCRIPTION

[0050] The following is combined with Figure 1-10 This application is described in further detail.

[0051] A die casting 1, referring to Figure 1 The die casting 1 includes an upper cylinder 11 and a lower cylinder 12, wherein the outer diameter and the inner diameter of the upper cylinder 11 are both larger than the lower cylinder 12, and thus the die casting 1 as a whole is in the shape of a circular cylinder that is first large and then small. The upper cylinder 11 includes a thick-walled area 111 and a thin-walled area 112, wherein the thin-walled area 112 is located at one end of the thick-walled area 111 away from the lower cylinder 12, the wall thickness of the thin-walled area 112 is less than the wall thickness of the thick-walled area 111, and the wall thickness of the thick-walled area 111 is equal to the wall thickness of the lower cylinder 12. A connecting ear 13 is provided around the thin-walled area 112, and an upper column port 14 and a lower column port 15 are respectively provided at one end of the upper cylinder 11 and the lower cylinder 12 away from each other, and the wall thickness of the specific upper column port 14 and the lower column port 15 is thicker than the wall thickness of the upper cylinder 11 or the lower cylinder 12.

[0052] The present application embodiment discloses an embedded dense die casting mold. Figure 2-6 An embedded compact die-casting mold is used for die-casting a die-casting part 1 in the above-mentioned prior art, and includes a fixed mold 2, a movable mold 3, and a core layer molding mechanism 4. The fixed mold 2 includes a fixed mold frame 21 and a fixed mold core 22, and the fixed mold core 22 is provided with a fixed mold cavity surface for molding the outer wall of one side of the die-casting part 1; the movable mold 3 includes a movable mold frame 31 and a movable mold core 32, and the movable mold core 32 is provided with a movable mold cavity surface for molding the outer wall of the other side of the die-casting part 1. The core layer molding mechanism 4 includes an upper core mold group 41 and a lower core mold group 42, wherein the upper core mold group 41 and the lower core mold group 42 are both fixedly embedded in the fixed mold frame 21, and are respectively located on both sides of the fixed mold core 22.

[0053] Reference Figure 5 and Figure 7The upper core module 41 includes an upper core-pulling driving member 411, an upper column core 412 and a dense core 413, wherein the upper column core 412 is used to form the inner side wall of the thick wall area 111 of the upper column 11, and the dense core 413 is used for secondary core filling and forming the inner side wall of the thin wall area 112 of the upper column 11. Specifically, the upper core-pulling driving member 411 is fixedly arranged on the end of the fixed mold frame 21 corresponding to the upper column 11 of the die casting 1, and the dense core 413 is slidably sleeved on the circumference of the upper column core 412. The driving ends of the upper core-pulling driving member 411 are respectively connected to the upper column core 412 and the dense core 413, and can respectively drive the upper column core 412 and the dense core 413 to slide back and forth toward the direction of the fixed mold core 22. In this embodiment, the upper core-pulling driving member 411 specifically uses a multi-stage servo cylinder.

[0054] Further, see Figure 8 , a vibrator is also provided on the inner side of the upper column core 412, which is used to make the upper column core 412 vibrate slightly during the pouring process, thereby promoting the full flow of the molten metal liquid. Specifically, the inner side wall of the upper column core 412 is provided with a heat insulation layer 4121 and a magnetic steel layer 4122, and the heat insulation layer 4121 is located between the upper column core 412 and the magnetic steel layer 4122. In addition, an eccentric rotor 4123 is also provided inside the upper column core 412, and the eccentric rotor 4123 can be electrically connected to the outside world. Then, when the eccentric rotor 4123 is energized, under the action of the magnetic field of the magnetic steel layer 4122, the eccentric rotor 4123 begins to rotate, and under the action of the centripetal force of the eccentric rotor 4123, the upper column core 412 can vibrate slightly.

[0055] Reference Figure 5 and Fig. 9 The lower core module 42 includes a lower core-pulling driving member 421 and a lower column core 422, wherein the lower column core 422 is used to form the inner side wall of the lower column 12. Specifically, the lower core-pulling driving member 421 is fixedly arranged at one end of the fixed mold frame 21 corresponding to the lower column 12 of the die casting 1, and the driving end of the lower core-pulling driving member 421 is connected to the lower column core 422, and can drive the lower column core 422 to slide back and forth toward the fixed mold core 22. In this embodiment, the lower core-pulling driving member 421 is specifically a servo cylinder.

[0056] Thus, when the upper core-pulling driving member 411 drives the upper column core 412 and the dense core 413 to slide toward the fixed mold core 22, and the lower core-pulling driving member 421 drives the lower column core 422 to slide toward the fixed mold core 22, the upper column core 412 and the lower column core 422 are pressed against each other, and through the fixed mold cavity surface of the fixed mold core 22, the movable mold cavity surface of the movable mold core 32, the upper column core 412, the dense core 413 and the lower column core 422 cooperate with each other to form a cavity 5 for molding the die-casting 1.

[0057] Reference Figure 4 , Figure 5 and Figure 6 , the fixed mold frame 21 is provided with a discharge barrel 211, and the movable mold core 32 is provided with a plane side-cut runner 321, and the discharge barrel 211, the runner 321 and the cavity 5 are interconnected. Specifically, the plane side-cut runner 321 corresponds to the cylindrical side wall of the annular column structure of the die casting 1, and extends along the central tangent of the column of the die casting 1, that is, during the pouring process, the molten metal liquid is poured in an "I" shape from the central tangent of the side wall of the annular column structure, and flows and closes along the annular outer circumference of the side wall of the cavity 5. In this embodiment, the connection between the runner 321 and the cavity 5 and the contact point between the upper column core 412 and the lower column core 422 are staggered, thereby preventing the molten metal liquid from having too much impact on the contact point between the upper column core 412 and the lower column core 422 when pouring, and preventing the formation of obvious parting lines or overflow flash on the inner side of the die casting 1.

[0058] Reference Figure 7 and Fig. 9 Furthermore, a connecting wedge 4124 is provided on one end surface of the upper column core 412 facing the lower column core 422, and a connecting wedge groove 4221 corresponding to the connecting wedge 4124 is opened on the lower column core 422. When the upper column core 412 and the lower column core 422 are pressed against each other, the connecting wedge 4124 is inserted into the connecting wedge groove 4221, so that the molten metal is not easy to penetrate between the upper column core 412 and the lower column core 422, which is beneficial to reduce the generation of overflow flash.

[0059] Reference Figure 4 , Figure 5 and Figure 6 , a plurality of overflow channels 6 and overflow cavities 7 are provided in both the fixed mold core 22 and the movable mold core 32, wherein the overflow channel 6 is used to connect the mold cavity 5 and the overflow cavity 7, and then the excess molten metal liquid can overflow into the overflow cavity 7 along the overflow channel 6, and the overflow cavity 7 is connected with an exhaust groove 322. In order to control the exhaust volume of the exhaust groove 322 and prevent the exhaust groove 322 from affecting the normal flow and pouring of the molten metal liquid due to the excessive opening of the exhaust groove 322, in this embodiment, the exhaust groove 322 is only provided in the movable mold core 32, and the opening depth of the exhaust groove 322 is 0.15mm.

[0060] Reference Figure 5 and Figure 6, the overflow cavities 7 are mainly distributed at the pouring end or thick wall position of the corresponding die casting 1. Specifically, several groups of overflow cavities 7 are located at the outer peripheral side of the annular column structure of the corresponding die casting 1 away from one end of the runner 321, and are evenly distributed along the center tangent; several groups of overflow cavities 7 are respectively located at the outer peripheral side of the upper column port 14 and the lower column port of the corresponding die casting 1. In the present embodiment, a total of three groups of overflow cavities 7 are arranged at the center tangent of the corresponding die casting 1, and three groups of overflow cavities 7 are also arranged at the peripheral side of the upper column port 14 and the lower column port of the corresponding die casting 1. Furthermore, in order to ensure that multiple groups of overflow cavities 7 can be fully exhausted and prevent the cooling of the molten metal from blocking part of the exhaust groove 322, the exhaust groove 322 connects all the overflow cavities 7 to each other.

[0061] Reference Figure 4 and Figure 5 A pressure control module 8 is also fixedly provided at one end of the fixed mold frame 21 away from the discharge barrel 211, wherein the pressure control module 8 is used to adjust the air pressure in the mold cavity 5 according to the die-casting process, so that the molten metal liquid can flow evenly and be fully exhausted. Specifically, a pressure control cavity 81 is provided in the pressure control module 8, and the exhaust groove 322 is interconnected with the pressure control cavity 81. The pressure control module 8 is also provided with a negative pressure tube 82 and a voltage-stabilizing tube 83, and the negative pressure tube 82 and the voltage-stabilizing tube 83 are both interconnected with the pressure control cavity 81. The negative pressure tube 82 is used to evacuate air and keep the pressure control cavity 81 in a negative pressure state, and the voltage-stabilizing tube 83 is used to inflate and keep the pressure control cavity 81 in a pressurized state.

[0062] Reference Figure 3 and Figure 4 In order to enable the fixed mold core 22 and the movable mold core 32 to better mold the molten metal and improve the problem that some areas are prone to overcooling or overheating, a circulating liquid temperature control system is also provided in the die-casting mold of the present application. Specifically, criss-crossing temperature control water channels 9 are provided in the fixed mold core 22 and the movable mold core 32, and the temperature control water channels 9 pass through the fixed mold frame 21 and the movable mold frame 31 to communicate with the outside world, so that cold or hot heat-conducting liquid can be circulated into the temperature control water channels 9, and thereby the temperature of the fixed mold core 22 and the movable mold core 32 can be controlled. Furthermore, the temperature control water channels 9 are evenly distributed along the circumferential side of the circular column structure of the die-casting 1, and the thinnest parts of the ends of the temperature control water channels 9 are all arranged correspondingly on the circumferential side of the corresponding thick-walled part of the die-casting 1, so as to achieve precise control over the molding of the thick-walled part of the die-casting 1.

[0063] This embodiment also discloses an embedded dense die-casting process, and is applicable to the above-mentioned embedded dense die-casting mold. For details, refer to Fig.10 , including the following steps:

[0064] S1, mold closing, the movable mold 3 and the fixed mold 2 are closed to each other, the upper core-pulling driving member 411 and the lower core-pulling driving member 421 respectively drive the upper column core 412 and the lower column core 422 to close to each other, and form a larger molding cavity, and the pressure control cavity 81 is evacuated through the negative pressure tube 82 and kept in a negative pressure state.

[0065] S2. Pouring: A certain amount of molten metal is poured into the lower barrel 211 at low pressure, and a heat transfer liquid at 180°C is circulated into the temperature-controlled waterway 9. When the molten metal fills the molding cavity, the vacuum pipe 82 is stopped for exhaust, and the larger molding cavity is waited for to be fully filled with the molten metal.

[0066] S3, maintain pressure and compaction. After the molten metal fills the larger molding cavity, start the vibrator inside the upper column core 412, and at the same time drive the compact core 413 toward the mold cavity 5 through the upper core-pulling drive 411 to compress the metal liquid in the larger molding cavity and restore the larger molding cavity to the target size of the mold cavity 5. In addition, the pressure control cavity 81 is ventilated and pressurized through the voltage-stabilizing tube 83, and it is kept in a pressurized state for a certain period of time.

[0067] S4, cooling, circulating a normal temperature coolant into the temperature control water channel 9 to cool the die casting 1 evenly.

[0068] S5, open the mold and take out the part. The movable mold 3 and the fixed mold 2 are separated first, and the upper core-pulling driving member 411 and the lower core-pulling driving member 421 simultaneously drive the upper column core 412, the dense core 413 and the lower column core 422 to slide out of the die-casting 1, so that the formed die-casting 1 can be taken out.

[0069] The implementation principle of an embedded dense die-casting mold in the embodiment of the present application is:

[0070] When die casting is required, the movable mold 3 and the fixed mold 2 are closed to each other, and the upper core-pulling driving member 411 and the lower core-pulling driving member 421 respectively drive the upper column core 412 and the lower column core 422 to press against each other and close. At this time, the fixed cavity surface of the fixed mold core 22, the movable cavity surface of the movable mold core 32, the upper column core 412 and the lower column core 422 form a molding cavity that is larger than the target die-casting part 1.

[0071] In the pouring process, since the pouring is directly into the larger molding cavity, the amount of molten metal in the molding cavity is greater than the pouring amount required for the target die-casting 1, and the temperature-controlled water channel 9 is filled with hot water, which can evenly heat the fixed mold core 22 and the movable mold core 32. At this time, the molten metal is not easy to cool down too quickly to prevent affecting the molding uniformity and exhaust. In addition, during the pouring process, the pressure control cavity 81 and the overflow cavity 7 maintain a negative pressure state, so that the gas molten metal in the cavity 5 can be fully discharged along the exhaust groove 322 during pouring.

[0072] Then, in the pressure-maintaining and densifying stage, as the eccentric rotor 4123 inside the upper column core 412 is started, the upper column core 412 vibrates, and at this time, the molten metal in the molding cavity can flow again under the vibration of the upper column core 412 and fill the internal pores. At the same time, the upper core-pulling drive 411 drives the compacting core 413 to slide toward the molding cavity, and the larger molding cavity is further reduced to the size of the target cavity 5, so that the molten metal further flows and is compacted in the thick wall part of the die casting 1, and the excess molten metal overflows from the pouring end or the thick wall part to the overflow cavity 7, and finally after uniform cooling and mold opening and taking out, the die casting 1 with high density at the pouring end and rear wall can be obtained.

[0073] This specific implementation manner is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the specific implementation manner as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. An embedded dense die-casting mold, characterized in that: include: A fixed die (2), the fixed die (2) comprising a fixed die frame (21) and a fixed die core (22), the fixed die core (22) being provided with a molding cavity surface for molding the outer side of the die casting (1); A movable mold (3), the movable mold (3) comprising a movable mold frame (31) and a movable mold core (32), the movable mold core (32) being provided with a movable mold cavity surface for molding the outer side of the die casting (1); A core layer forming mechanism (4), the core layer forming mechanism (4) comprising an upper core module (41) and a lower core module (42), the upper core module (41) and the lower core module (42) both being embedded and fixed in the fixed mold frame (21) and respectively located on both sides of the fixed mold core (22), the upper core module (41) comprising an upper core pulling drive member (411), an upper column core (412) and a compact core (413), the lower core module (42) comprising a lower core pulling drive member (421) and a lower column core (42 2), the upper core-pulling driving member (411) is used to drive the upper column core (412) and the dense core (413) to slide back and forth in the direction of the fixed mold core (22), and the lower core-pulling driving member (421) is used to drive the lower column core (422) to slide back and forth in the direction of the fixed mold core (22); the fixed mold cavity surface, the movable mold cavity surface, the upper column core (412), the dense core (413) and the lower column core (422) cooperate with each other to form a mold cavity; The dense core (413) is slidably sleeved on the circumference of the upper column core (412), and the dense core (413) is used for secondary core filling when pouring is completed, and can cooperate with the upper column core (412) and the lower column core (422) to form the inner wall of the die casting (1); The fixed mold frame (21) is provided with a discharge barrel (211), the movable mold core (32) is provided with a plane side-cut runner (321), the discharge barrel (211), the runner (321) and the mold cavity (5) are connected to each other, the runner (321) corresponds to the outer wall of the circular column structure of the die casting (1), and is poured in a straight line along the central tangent line of the circular column structure of the die casting (1), the fixed mold core (22) and the movable mold core (32) are both provided with a plurality of overflow channels (6) and overflow cavities (7), and a plurality of overflow channels (6) and overflow cavities (7) are provided. The overflow cavity (7) and the mold cavity (5) are connected to each other through the overflow channel (6); the movable mold core (32) is provided with an exhaust groove (322), and the exhaust groove (322) is connected to the overflow cavity (7); a plurality of groups of the overflow cavities (7) are located on the outer peripheral side of the circular ring column structure of the corresponding die casting (1) away from one end of the runner (321), and are evenly distributed along the central tangent of the circular ring column structure of the die casting (1); and a plurality of groups of the overflow cavities (7) are located on the outer peripheral side of the two end ports of the circular ring column structure of the corresponding die casting (1).

2. The embedded dense die-casting mold according to claim 1, characterized in that: A vibrating part is embedded inside the upper column core (412).

3. The embedded dense die-casting mold according to claim 2, characterized in that: The connection point between the runner (321) and the mold cavity (5) and the intersection point between the upper column core (412) and the lower column core (422) are staggered; A connecting wedge platform (4124) is provided at one end of the upper column core (412) facing the lower column core (422), and a connecting wedge groove (4221) corresponding to the connecting wedge platform (4124) is provided at the end of the lower column core (422). When the upper column core (412) and the lower column core (422) are attached to and pressed against each other, the connecting wedge platform (4124) is inserted into the connecting wedge groove (4221).

4. The embedded dense die-casting mold according to claim 3, characterized in that: The exhaust groove (322) connects a plurality of groups of overflow chambers (7) to each other.

5. The embedded dense die-casting mold according to claim 4, characterized in that: A pressure control module (8) is provided at one end of the fixed mold frame (21) away from the discharge barrel (211), a pressure control chamber (81) is provided inside the pressure control module (8), the exhaust groove (322) is communicated with the pressure control chamber (81), the pressure control module (8) is provided with a negative pressure tube (82) and a pressure stabilizing tube (83), and the negative pressure tube (82) and the pressure stabilizing tube (83) are both communicated with the pressure control chamber (81).

6. The embedded dense die-casting mold according to claim 5, characterized in that: A plurality of groups of temperature-controlling water channels (9) are arranged on the inner sides of the fixed mold core (22) and the movable mold core (32); the temperature-controlling water channels (9) are evenly distributed along the circular column structure of the die-casting (1); and the thinnest part at the end of the temperature-controlling water channel (9) is arranged at the thick wall part of the corresponding die-casting (1).

7. An embedded dense die-casting process, applicable to the embedded dense die-casting mold according to claim 6, characterized in that: The following steps are involved: S1, mold closing: the movable mold (3) and the fixed mold (2) are closed to each other, the upper core-pulling driving member (411) and the lower core-pulling driving member (421) respectively drive the upper column core (412) and the lower column core (422) to close to each other and form a molding cavity, and at the same time, the negative pressure tube (82) is used to evacuate and reduce pressure, so as to keep the pressure control cavity (81) in a negative pressure state; S2, pouring: pouring a certain amount of molten metal, and at the same time, introducing heat transfer liquid into the temperature control water channel (9), and when the molten metal fills the molding cavity, stopping the vacuum pipe (82) from evacuating air; S3, maintaining pressure and compacting: when the molten metal fills the molding cavity, the vibrating member inside the upper column core (412) is started, and at the same time, the compacting core (413) is driven into the molding cavity by the upper core-pulling driving member (411), thereby compressing the molten metal in the molding cavity and restoring the molding cavity to the target size of the molding cavity (5), and at the same time, the pressure-stabilizing tube (83) is used to ventilate and pressurize the pressure-controlled cavity (81), thereby keeping the pressure-controlled cavity (81) in a pressurized state, and maintaining the pressure for a certain period of time; S4, cooling: introducing a cooling liquid into the temperature-control water channel (9); S5, opening the mold and removing the part: the movable mold (3) and the fixed mold (2) are separated from each other, and the upper core-pulling driving member (411) and the lower core-pulling driving member (421) respectively drive the upper column core (412), the dense core (413) and the lower column core (422) to slide out, thereby obtaining a formed die-casting part (1).

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