Vacuum die-casting equipment and die-casting method for producing engine front cover

Abstract

The present invention discloses a vacuum die-casting device and a die-casting method for producing an engine front cover, and relates to the field of die-casting devices. In the present invention, during the process of the injection component injecting molten metal into the mold cavity, the injection component drives the ejection component to store power through the transmission component, and when the mold cavity is about to be filled with molten metal, the locking component is driven by the transmission component to release the limit of the ejection component. At this time, the ejection component drives the sealing plug to eject upward quickly, so that the sealing plug is quickly sealed and clamped in the sealing groove, and the vacuum guide groove is closed and sealed. Through the rapid closing and sealing of the vacuum guide groove, the vacuum guide groove can be in an open state during the process of injecting molten metal into the mold cavity, and the mold cavity is continuously vacuumed, thereby improving the vacuuming effect of the mold cavity, preventing the air rolling phenomenon from occurring during the liquid injection process and causing pores in the casting. At the same time, through the rapid sealing of the vacuum guide groove, the metal liquid can be prevented from entering the vacuum guide groove and subsequent vacuum equipment.

Description

Technical Field

[0001] The invention belongs to the field of die-casting equipment, and in particular, relates to a vacuum die-casting equipment and a die-casting method for producing an engine front cover. Background Art

[0002] At present, die casting technology is widely used in the fields of automobiles, 3C, etc., with the advantages of short molding cycle, high production efficiency, and environmental friendliness. However, during the die casting process, the punch quickly injects the molten metal into the cavity, causing air entrainment, which leads to the existence of pores in the final casting, affecting the quality of the casting.

[0003] Chinese patent CN106975738B discloses a vacuum die-casting device and a high vacuum die-casting method, which reduces the air entrainment phenomenon during the die-casting process by evacuating the cavity, reduces the pores in the casting, and improves the quality of the casting. However, in the prior art, since the speed at which the molten metal is injected into the cavity is relatively fast, in order to prevent the molten metal from entering the vacuum-drawing pipeline, it is necessary to evacuate the cavity before die-casting, and then inject the molten metal into the cavity after closing the vacuum-drawing pipeline. However, during the injection, as the molten metal is gradually injected into the cavity, the remaining air in the cavity is compressed, and air entrainment still occurs in the cavity, resulting in pores in the casting, which affects the quality of the casting. Summary of the invention

[0004] In view of the problems in the related art, the present invention proposes a vacuum die-casting device and a die-casting method for producing an engine front cover to overcome the above-mentioned technical problems existing in the existing related art.

[0005] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

[0006] The present invention is a vacuum die-casting device, comprising a die-casting machine, on which a fixed die is fixedly mounted, on which a movable die that can be closed with the fixed die is slidably mounted, a cavity is arranged between the fixed die and the movable die, and on which an injection assembly that is connected with the cavity in the fixed die is also fixedly mounted;

[0007] The fixed mold is provided with a vacuum mechanism, the vacuum mechanism comprising a connecting nozzle and a vacuum guide groove, the connecting nozzle is fixedly installed at the top of the fixed mold, the vacuum guide groove is opened in the mold wall of the fixed mold, one end of the vacuum guide groove is connected with the mold cavity in the fixed mold, and the other end of the vacuum guide groove is connected with the connecting nozzle;

[0008] The fixed mold is also provided with a sealing mechanism for sealing the vacuum guide groove, the sealing mechanism comprising a sealing plug, a sealing groove, an ejection assembly, a limit assembly and a transmission assembly. The sealing groove is provided on the inner wall of the cavity of the fixed mold and is connected with one end of the vacuum guide groove. The sealing plug is installed below the sealing groove through the ejection assembly. The limit assembly is used to limit the elastic assembly, and the limit assembly and the ejection assembly are both connected to the injection assembly through the transmission assembly; so that when the injection assembly injects molten metal into the cavity, the ejection assembly can be driven to accumulate force, and when the cavity is about to be filled with molten metal, the locking assembly can be driven to release the limit on the ejection assembly, so that the ejection assembly can drive the sealing plug to eject and seal the card in the sealing groove.

[0009] Furthermore, the injection assembly includes a hydraulic telescopic shaft, a punch chamber and a feed pipe. The punch chamber is fixedly installed on the die-casting machine and is connected to the cavity of the fixed mold. One end of the feed pipe is connected to the punch chamber, and the other end is connected to the metal melting furnace. The hydraulic telescopic shaft is fixedly installed on one side of the punch chamber, and the telescopic end of the hydraulic telescopic shaft is fixedly installed with a punch that is slidably clamped inside the punch chamber.

[0010] Furthermore, the ejection assembly includes an ejection rod, which is slidably inserted into the interior of the fixed mold, the sealing plug is fixedly installed on the bottom end of the ejection rod, a limiting plate is fixedly installed on the upper end of the ejection rod, and a bottom plate located below the limiting plate is slidably installed on the lower end of the ejection rod, and the surface of the ejection rod is provided with an ejection spring abutting between the bottom plate and the limiting plate.

[0011] Furthermore, the limit assembly includes a slide groove opened in the mold wall of the fixed mold, an elastic pin is slidably installed in the slide groove, one end of the elastic pin is abutted with a pressure spring, and the other end of the elastic pin is provided with a limit groove that can be engaged with the top surface of the limit plate for limiting.

[0012] Furthermore, the elastic pin is provided with a through slot which passes through from top to bottom, one end of the through slot is provided with a guiding inclined surface, a wedge block is slidably installed inside the through slot, and a push-pull rod extending to the top of the fixed mold is fixedly installed on the top of the wedge block.

[0013] Furthermore, the ejection assembly further comprises a screw rod and a connecting strip, wherein the connecting strip is fixedly mounted on the outer ring of the top surface of the bottom plate, and the connecting strip extends upward to above the fixed mold, and a top plate is fixedly mounted on the top end of the connecting strip;

[0014] The screw rod is rotatably installed on the top end of the fixed mold, and a screw rod pair is rotatably installed on the screw rod. A connecting plate is fixedly installed on one side of the screw rod pair, and a connecting rod is fixedly installed on the bottom end of the connecting plate. The bottom end of the connecting rod is fixedly connected to the top plate, and a connecting frame is slidably installed on the connecting rod, and one end of the connecting frame is fixedly connected to the top end of the push-pull rod.

[0015] Furthermore, the transmission assembly includes a driven wheel, a rack and a transmission shaft, the rack is fixedly mounted on the top of the telescopic end of the hydraulic telescopic shaft, the transmission shaft is rotatably mounted on the die-casting machine, the bottom end of the transmission shaft is fixedly mounted with a gear meshing with the rack, the top end of the transmission shaft is fixedly mounted with a transmission wheel, the driven wheel is fixedly mounted on the bottom end of the screw rod, and the transmission wheel and the driven wheel are connected by a transmission belt.

[0016] Furthermore, the limiting plate is an inverted truncated cone structure, the top surface of one end of the elastic pin is provided with an inclined surface, the top end of the ejection rod extends to the bottom of the top plate, and a stop block is fixedly installed on the top end of the ejection rod.

[0017] Furthermore, a pressure chamber connected to the vacuum guide groove is provided in the mold wall of the fixed mold, a hydraulic plug is sealingly and slidably installed in the pressure chamber, a piston rod is fixedly installed at one end of the hydraulic plug, one end of the piston rod seals and slides and extends into the slide groove and is fixedly connected to one end of the elastic pin;

[0018] The top end of the fixed mold is detachably mounted with an inlay block by means of bolts, and the inlay block is engaged with the fixed mold to form a vacuum guide groove and a pressure chamber.

[0019] The present invention also discloses a die-casting method for producing an engine front cover, the specific steps of which are:

[0020] First, the movable mold is slid and closed with the fixed mold to form a closed cavity between the fixed mold and the movable mold. Then, a vacuum pump is used to evacuate the closed cavity through the connecting nozzle and the vacuum guide groove. Then, the molten metal is injected into the closed cavity through the injection assembly.

[0021] During the process of injecting molten metal into the mold cavity, the vacuum pump continuously evacuates the mold cavity. At the same time, the injection component drives the ejection component through the transmission component to accumulate force, and when the mold cavity is about to be filled with molten metal, the locking component is driven by the transmission component to release the limit on the ejection component. At this time, the ejection component drives the sealing plug to eject upward rapidly, so that the sealing plug is quickly sealed and connected to the sealing groove, closing and sealing the vacuum guide groove.

[0022] The present invention has the following beneficial effects:

[0023] 1. In the present invention, during the process of the injection assembly injecting molten metal into the mold cavity, the injection assembly drives the ejection assembly to accumulate force through the transmission assembly, and when the mold cavity is about to be filled with molten metal, the locking assembly is driven by the transmission assembly to release the limit on the ejection assembly. At this time, the ejection assembly drives the sealing plug to eject upward rapidly, so that the sealing plug is quickly sealed and engaged in the sealing groove, and the vacuum guide groove is closed and sealed. By quickly closing and sealing the vacuum guide groove, the vacuum guide groove can be kept in an open state during the process of injecting molten metal into the mold cavity, and the mold cavity is continuously vacuumed, thereby improving the vacuuming effect of the mold cavity, preventing air entrainment during the injection process and causing pores in the casting, thereby improving the quality of the casting. At the same time, through the rapid sealing of the vacuum guide groove, the molten metal can be prevented from entering the vacuum guide groove and subsequent vacuum equipment, which can not only prevent the vacuum equipment from being blocked and damaged by the molten metal, but also prevent the loss of molten metal during the die-casting process, thereby ensuring the normal progress of the die-casting process.

[0024] 2. In the present invention, when the locking assembly is not triggered to unlock in time, causing the metal liquid to enter the vacuum guide groove, the metal liquid can enter the pressure chamber along the vacuum guide groove and drive the hydraulic plug to move to the right through the liquid pressure, and then the hydraulic plug drives the elastic pin to move to the right through the piston rod to release the lock of the ejection assembly. After that, the ejection assembly drives the sealing plug to quickly seal and engage in the sealing groove, closing and sealing the vacuum guide groove to prevent the metal liquid from continuing to flow into the vacuum guide groove and subsequent vacuum equipment, further preventing the vacuum equipment from being blocked and damaged by the metal liquid, and at the same time preventing the metal liquid from being lost during the die-casting process, ensuring the normal progress of the die-casting process; and the top of the fixed mold is detachably installed with an inlay block by bolts, the inlay block is engaged with the fixed mold to form the vacuum guide groove and the pressure chamber, and when metal liquid enters the vacuum guide groove and the pressure chamber, the inlay block can be disassembled and removed after the die-casting is completed, thereby facilitating the cleaning of the vacuum guide groove and the pressure chamber.

[0025] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the invention, the drawings required for describing the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For ordinary technicians in this field, they can also obtain drawings based on these drawings without paying creative work.

[0027] Figure 1 This is one of the three-dimensional structural schematic diagrams of the vacuum die-casting equipment of the present invention;

[0028] Figure 2 For the present invention Figure 1 A local enlarged structural schematic diagram;

[0029] Figure 3 This is the second schematic diagram of the three-dimensional structure of the vacuum die-casting equipment of the present invention;

[0030] Figure 4 For the present invention Figure 3 A schematic diagram of the local enlarged structure at B;

[0031] Figure 5 The third schematic diagram of the three-dimensional structure of the vacuum die-casting equipment of the present invention;

[0032] Figure 6 For the present invention Figure 5 A schematic diagram of the local enlarged structure at C;

[0033] Figure 7 This is one of the three-dimensional structural schematic diagrams of the fixed mold of the present invention;

[0034] Figure 8 For the present invention Figure 7 A schematic diagram of the local enlarged structure at D;

[0035] Fig. 9 The second schematic diagram of the three-dimensional structure of the fixed mold of the present invention;

[0036] Fig.10 For the present invention Fig. 9 Schematic diagram of the local enlarged structure at E.

[0037] In the figure: 1. die casting machine; 11. fixed die; 12. movable die; 13. hydraulic telescopic shaft; 14. punching chamber; 15. feed pipe; 16. punch; 1101. inlay block; 2. vacuum pumping mechanism; 21. connecting nozzle; 22. vacuum pumping guide groove; 3. sealing mechanism; 31. screw rod; 32. driven wheel; 33. transmission belt; 34. screw rod pair; 35. connecting plate; 36. connecting rod; 37. top plate; 38. connecting frame; 39. push-pull rod; 310. rack; 3 11. Gear; 312. Transmission shaft; 313. Transmission wheel; 314. Elastic pin; 315. Connecting strip; 316. Bottom plate; 317. Ejection rod; 318. Sealing plug; 319. Sealing groove; 320. Pressure chamber; 321. Hydraulic plug; 322. Piston rod; 323. Stop block; 324. Ejection spring; 325. Limiting plate; 326. Limiting groove; 327. Guide ramp; 328. Slide groove; 329. Pressure spring; 330. Wedge block. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the invention to clearly and completely describe the technical solutions in the embodiments of the invention. Obviously, the described embodiments are only part of the embodiments of the invention, not all of the embodiments. Based on the embodiments in the invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the invention.

[0039] In the description of the present invention, it is necessary to understand that the terms "opening", "upper", "lower", "top", "middle", "inside" and the like indicating orientation or positional relationship are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the invention.

[0040] Example 1: Please refer to Figure 1 , Figure 3 , Figure 7 , Figure 8 As shown, the present invention is a vacuum die-casting equipment, including a die-casting machine 1, on which a fixed die 11 is fixedly installed, on which a movable die 12 that can be closed with the fixed die 11 is slidably installed, a cavity is arranged between the fixed die 11 and the movable die 12, and on the die-casting machine 1 an injection assembly that is connected to the cavity in the fixed die 11 is also fixedly installed; a vacuum pumping mechanism 2 is installed on the fixed die 11, and the vacuum pumping mechanism 2 includes a connecting nozzle 21 and a vacuum pumping guide groove 22, the connecting nozzle 21 is fixedly installed on the top of the fixed die 11, the vacuum pumping guide groove 22 is opened in the mold wall of the fixed die 11, and one end of the vacuum pumping guide groove 22 is connected to the cavity in the fixed die 11, and the other end of the vacuum pumping guide groove 22 is connected to the connecting nozzle 21; the fixed die 11 is also equipped with a vacuum pumping mechanism 2 for pumping the vacuum pumping mechanism 2 into the fixed die 11. The guide groove 22 seals the sealing mechanism 3, and the sealing mechanism 3 includes a sealing plug 318, a sealing groove 319, an ejection assembly, a limit assembly and a transmission assembly. The sealing groove 319 is opened on the inner wall of the cavity of the fixed mold 11 and is connected with one end of the vacuum guide groove 22. The sealing plug 318 is installed below the sealing groove 319 through the ejection assembly. The limit assembly is used to limit the elastic assembly, and the limit assembly and the ejection assembly are both connected to the injection assembly through the transmission assembly; when the injection assembly injects molten metal into the cavity, the ejection assembly can be driven to accumulate force, and when the cavity is about to be filled with molten metal, the locking assembly is driven to release the limit on the ejection assembly, so that the ejection assembly can drive the sealing plug 318 to eject the seal and be connected in the sealing groove 319.

[0041] Specifically, when the vacuum die-casting equipment is working, the movable mold 12 is first slid and closed with the fixed mold 11 to form a closed cavity between the fixed mold 11 and the movable mold 12, and then the closed cavity is evacuated through the connecting nozzle 21 and the vacuum guide groove 22 by a vacuum pump, and then the molten metal is injected into the closed cavity by the injection assembly; during the process of injecting the molten metal into the cavity, the vacuum pump continuously evacuates the cavity, and at the same time, the injection assembly drives the ejection assembly to accumulate power through the transmission assembly, and when the cavity is about to be filled with molten metal, the locking assembly is driven by the transmission assembly to release the limit of the ejection assembly, and at this time, the ejection assembly drives the sealing plug 318 to eject upward quickly, so that the sealing plug 318 is quickly sealed and clamped in the sealing groove 319, and the vacuum guide groove 22 is closed and sealed;

[0042] By quickly closing and sealing the vacuum guide groove 22, the vacuum guide groove 22 can be kept in an open state during the process of injecting molten metal into the cavity, and the cavity can be continuously vacuumed, thereby improving the vacuuming effect of the cavity, preventing air entrainment during the injection process from causing air holes in the casting, and improving the quality of the casting. At the same time, the rapid sealing of the vacuum guide groove 22 can prevent molten metal from entering the vacuum guide groove 22 and subsequent vacuum equipment, which can not only prevent the vacuum equipment from being blocked and damaged by molten metal, but also prevent the loss of molten metal during the die-casting process, thereby ensuring the normal progress of the die-casting process.

[0043] Example 2: Please refer to Figure 3-Figure 6 As shown, the difference between this embodiment and the above embodiment is that the injection assembly includes a hydraulic telescopic shaft 13, a punch chamber 14 and a feed pipe 15, the punch chamber 14 is fixedly mounted on the die-casting machine 1 and communicated with the cavity of the fixed mold 11, one end of the feed pipe 15 is communicated with the punch chamber 14, and the other end is communicated with the metal melting furnace, the hydraulic telescopic shaft 13 is fixedly mounted on one side of the punch chamber 14, and the telescopic end of the hydraulic telescopic shaft 13 is fixedly mounted with a punch 16 that is slidably mounted inside the punch chamber 14;

[0044] During the injection process, the metal furnace transports the molten metal into the punch chamber 14 through the feed pipe 15, and then the punch 16 is driven to move into the punch chamber 14 through the telescopic end of the hydraulic telescopic shaft 13, so that the punch 16 squeezes and injects the metal liquid in the punch chamber 14 into the mold cavity.

[0045] Example 3: Please refer to Figure 1-Figure 10As shown, the difference between this embodiment and the above embodiment is that the ejection assembly includes an ejection rod 317, the ejection rod 317 is slidably inserted into the interior of the fixed mold 11, the bottom end of the ejection rod 317 is fixedly installed with a sealing plug 318, the upper end of the ejection rod 317 is fixedly installed with a limiting plate 325, the lower end of the ejection rod 317 is slidably installed with a bottom plate 316 located below the limiting plate 325, and the surface of the ejection rod 317 is covered with an ejection spring 324 abutting between the bottom plate 316 and the limiting plate 325; the limiting assembly includes an opening A slide groove 328 is provided in the mold wall of the fixed mold 11, and an elastic pin 314 is slidably installed in the slide groove 328. A pressure spring 329 is installed at one end of the elastic pin 314, and a limiting groove 326 that can be engaged with the top surface of the limiting plate 325 is provided at the other end of the elastic pin 314; a through groove that runs through the upper and lower parts is provided on the elastic pin 314, and a guide inclined surface 327 is provided at one end of the through groove. A wedge block 330 is slidably installed inside the through groove, and a push-pull rod 39 extending to the top of the fixed mold 11 is fixedly installed on the top of the wedge block 330;

[0046] The ejection assembly also includes a screw rod 31 and a connecting strip 315. The connecting strip 315 is fixedly mounted on the outer ring of the top surface of the bottom plate 316, and the connecting strip 315 extends upward to the top of the fixed mold 11. The top of the connecting strip 315 is fixedly mounted with a top plate 37. The screw rod 31 is rotatably mounted on the top of the fixed mold 11. A screw rod pair 34 is rotatably mounted on the screw rod 31. A connecting plate 35 is fixedly mounted on one side of the screw rod pair 34. A connecting rod 36 is fixedly mounted on the bottom end of the connecting plate 35. The bottom end of the connecting rod 36 is fixedly connected to the top plate 37. A connecting frame 38 is slidably mounted on the connecting rod 36. One end of the connecting frame 38 is fixedly connected to the top of the push-pull rod 39; the transmission assembly includes a driven wheel 32, a rack 310 and a transmission shaft 312, the rack 310 is fixedly installed on the top of the telescopic end of the hydraulic telescopic shaft 13, the transmission shaft 312 is rotatably installed on the die-casting machine 1, the bottom end of the transmission shaft 312 is fixedly installed with a gear 311 meshing and transmission-connected with the rack 310, the top of the transmission shaft 312 is fixedly installed with a transmission wheel 313, the driven wheel 32 is fixedly installed at the bottom end of the screw rod 31, and the transmission wheel 313 and the driven wheel 32 are connected through a transmission belt 33;

[0047] When the telescopic end of the hydraulic telescopic shaft 13 moves to the left and drives the punch 16 to squeeze and inject the molten metal into the cavity, the hydraulic telescopic shaft 13 drives the rack 310 to move to the left synchronously. At this time, the rack 310 engages the driving gear 311 to rotate, thereby driving the transmission shaft 312 to rotate. When the transmission shaft 312 rotates, it drives the screw rod 31 to rotate through the cooperation of the transmission wheel 313, the transmission belt 33 and the driven wheel 32. When the screw rod 31 rotates, it drives the screw pair 34 to move upward through the threaded transmission. At the same time, the screw pair 34 drives the connecting rod 36, the top plate 37, the connecting strip 315 and the bottom plate 316 to move upward synchronously through the connecting plate 35. At this time, the bottom plate 316 squeezes and contracts the ejection spring 324 to store energy. When the molten metal in the cavity is about to fill the cavity, the top plate 37 moves to the bottom end of the connecting frame 38 and pushes the connecting frame 38 upward, so that the connecting frame 38 drives the wedge block 330 to move upward through the push-pull rod 39. When the wedge block 330 moves upward, it pushes the elastic pin 314 to the right through the sliding contact with the guide inclined surface 327, so that the limiting groove 326 at one end of the elastic pin 314 is offset from the limiting plate 325, and the limiting plate 325 is no longer limited. When the ejection spring 324 is compressed under the action of external force, the ejection spring 324 will generate an elastic force to resist deformation and store energy. When the external force is removed (that is, the limiting plate 325 is released from the limit), the ejection spring 324 will return to its original state under the action of the elastic force, quickly release the stored energy, and convert the released energy into kinetic energy, thereby causing the limiting plate 325 to eject upward rapidly under the elastic force of the ejection spring 324, and drive the ejection rod 317 and the sealing plug 318 to move upward synchronously, so that the sealing plug 318 is quickly sealed and clamped in the sealing groove 319, the vacuum guide groove 22 is blocked and sealed, and the metal liquid is prevented from entering the vacuum guide groove 22.

[0048] Furthermore, the limiting plate 325 is an inverted truncated cone structure, the top surface of one end of the elastic pin 314 is provided with an inclined surface, the top end of the ejection rod 317 extends to the bottom of the top plate 37, and the top end of the ejection rod 317 is fixedly installed with a stop block 323;

[0049] When the die casting is completed, the hydraulic telescopic shaft 13 drives the punch 16 to move right and reset, and the hydraulic telescopic shaft 13 drives the screw 31 to rotate in the opposite direction through the transmission assembly. At this time, the screw 31 drives the screw pair 34 to move downward and reset through the threaded transmission. At the same time, the screw pair 34 drives the connecting rod 36, the top plate 37, the connecting strip 315 and the bottom plate 316 to move downward and reset synchronously through the connecting plate 35. At the same time, the top plate 37 moves the stop block 323 downward to abut and move, so that the stop block 323 drives the ejection rod 317 and the limit plate 325 to move downward and reset. When the limit plate 325 moves past the position of the elastic pin 314 When the locking cam 330 is in the unlocked state, the locking cam 330 is in the unlocked state, and the locking cam 330 is in the unlocked state.

[0050] Furthermore, a pressure chamber 320 communicating with the vacuum guide groove 22 is provided in the mold wall of the fixed mold 11, a hydraulic plug 321 is sealingly and slidably installed in the pressure chamber 320, a piston rod 322 is fixedly installed at one end of the hydraulic plug 321, one end of the piston rod 322 extends sealingly and slidably into the slide groove 328, and is fixedly connected to one end of the elastic pin 314;

[0051] When the locking assembly is not triggered to unlock in time, causing the metal liquid to enter the vacuum guide groove 22, the metal liquid can enter the pressure chamber 320 along the vacuum guide groove 22, and drive the hydraulic plug 321 to move rightward through the hydraulic pressure, and then the hydraulic plug 321 drives the elastic pin 314 to move rightward through the piston rod 322, so that the elastic pin 314 releases the limit plate 325, and then the limit plate 325 is quickly ejected upward under the elastic force of the ejection spring 324, and drives the ejection rod 317 and the sealing plug 318 to move upward synchronously, so that the sealing plug 318 is quickly sealed and connected to the sealing groove 319, thereby blocking the vacuum guide groove 22. The seal prevents the molten metal from continuing to be transported to the vacuum guide groove 22 and the subsequent vacuum equipment, further prevents the vacuum equipment from being blocked and damaged by the molten metal, and prevents the loss of molten metal during the die-casting process, thereby ensuring the normal progress of the die-casting process; and the top of the fixed mold 11 is detachably installed with an inlay block 1101 by bolts, and the inlay block 1101 is engaged with the fixed mold 11 to form the vacuum guide groove 22 and the pressure chamber 320. When the molten metal enters the vacuum guide groove 22 and the pressure chamber 320, the inlay block 1101 can be removed after the die-casting is completed, thereby facilitating the cleaning of the vacuum guide groove 22 and the pressure chamber 320, so that the equipment can be quickly restored to cleanliness.

[0052] Embodiment 4: This embodiment discloses a die-casting method for producing an engine front cover, and the specific steps are as follows:

[0053] First, the movable mold 12 is slid and closed with the fixed mold 11, so that a closed engine front cover cavity is formed between the fixed mold 11 and the movable mold 12, and then the closed cavity is evacuated through the connecting nozzle 21 and the vacuum guide groove 22 by a vacuum pump, and then the molten metal is injected into the closed cavity through the injection assembly;

[0054] During the process of injecting molten metal into the mold cavity, the vacuum pump continuously evacuates the mold cavity. At the same time, the injection component drives the ejection component to accumulate force through the transmission component, and when the mold cavity is about to be filled with molten metal, the locking component is driven by the transmission component to release the limit on the ejection component. At this time, the ejection component drives the sealing plug 318 to eject upward rapidly, so that the sealing plug 318 is quickly sealed and connected in the sealing groove 319, closing and sealing the vacuum guide groove 22.

[0055] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0056] The preferred embodiments of the invention disclosed above are only used to help explain the invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the invention, so that those skilled in the art can understand and use the invention well.

Claims

1. A vacuum die-casting device, comprising a die-casting machine, characterized in that: The die-casting machine is fixedly provided with a fixed die, a movable die that can be closed with the fixed die is slidably provided with the die-casting machine, a cavity is provided between the fixed die and the movable die, and an injection assembly that is connected with the cavity in the fixed die is also fixedly provided with the die-casting machine, and the injection assembly includes a hydraulic telescopic shaft, a punching chamber and a feed pipe; The fixed mold is provided with a vacuum mechanism, the vacuum mechanism comprising a connecting nozzle and a vacuum guide groove, the connecting nozzle is fixedly installed at the top of the fixed mold, the vacuum guide groove is opened in the mold wall of the fixed mold, one end of the vacuum guide groove is connected with the mold cavity in the fixed mold, and the other end of the vacuum guide groove is connected with the connecting nozzle; The fixed mold is also provided with a sealing mechanism for sealing the vacuum guide groove, the sealing mechanism comprising a sealing plug, a sealing groove, an ejection assembly, a limiting assembly and a transmission assembly, the sealing groove being arranged on the inner wall of the cavity of the fixed mold and being communicated with one end of the vacuum guide groove, the sealing plug being installed below the sealing groove through the ejection assembly, the limiting assembly being used for limiting the elastic assembly, and the limiting assembly and the ejection assembly being both connected to the injection assembly through the transmission assembly; so that when the injection assembly injects molten metal into the cavity, the ejection assembly can be driven to store force, and when the cavity is about to be filled with molten metal, the locking assembly can be driven to release the limiting of the ejection assembly, so that the ejection assembly can drive the sealing plug to eject and seal the card in the sealing groove; The ejection assembly includes an ejection rod, which is slidably inserted into the interior of the fixed mold, the sealing plug is fixedly installed on the bottom end of the ejection rod, a limit plate is fixedly installed on the upper end of the ejection rod, a bottom plate located below the limit plate is slidably installed on the lower end of the ejection rod, and an ejection spring abutting between the bottom plate and the limit plate is mounted on the surface of the ejection rod; The limit assembly comprises a slide groove provided in the wall of the fixed mold, an elastic pin is slidably installed in the slide groove, one end of the elastic pin is abutted against a pressure spring, and the other end of the elastic pin is provided with a limit groove capable of engaging with the top surface of the limit plate for limit. The elastic pin is provided with a through slot which passes through from top to bottom, one end of which is provided with a guiding inclined surface, a wedge block is slidably installed inside the through slot, and a push-pull rod extending to the top of the fixed mold is fixedly installed on the top of the wedge block; The ejection assembly also includes a screw rod and a connecting strip, wherein the connecting strip is fixedly mounted on the outer ring of the top surface of the bottom plate, and the connecting strip extends upward to the top of the fixed mold, and a top plate is fixedly mounted on the top of the connecting strip; The screw is rotatably mounted on the top of the fixed mold, a screw pair is rotatably mounted on the screw, a connecting plate is fixedly mounted on one side of the screw pair, a connecting rod is fixedly mounted on the bottom end of the connecting plate, the bottom end of the connecting rod is fixedly connected to the top plate, a connecting frame is slidably mounted on the connecting rod, and one end of the connecting frame is fixedly connected to the top end of the push-pull rod; The transmission assembly includes a driven wheel, a rack and a transmission shaft. The rack is fixedly mounted on the top of the telescopic end of the hydraulic telescopic shaft. The transmission shaft is rotatably mounted on the die-casting machine. A gear meshing with the rack is fixedly mounted on the bottom end of the transmission shaft. A transmission wheel is fixedly mounted on the top end of the transmission shaft. The driven wheel is fixedly mounted on the bottom end of the screw rod. The transmission wheel and the driven wheel are connected via a transmission belt.

2. A vacuum die-casting device according to claim 1, characterized in that: The punch chamber is fixedly mounted on the die-casting machine and communicated with the cavity of the fixed mold, one end of the feed pipe is communicated with the punch chamber, and the other end is communicated with the metal melting furnace, the hydraulic telescopic shaft is fixedly mounted on one side of the punch chamber, and the telescopic end of the hydraulic telescopic shaft is fixedly mounted with a punch that is slidably mounted inside the punch chamber.

3. A vacuum die-casting device according to claim 2, characterized in that: The limiting plate is an inverted truncated cone structure, the top surface of one end of the elastic pin is provided with an inclined surface, the top end of the ejection rod extends to the bottom of the top plate, and a stop block is fixedly installed on the top end of the ejection rod.

4. A vacuum die-casting device according to claim 3, characterized in that: A pressure chamber connected to the vacuum guide groove is provided in the mold wall of the fixed mold, a hydraulic plug is sealingly and slidably installed in the pressure chamber, a piston rod is fixedly installed at one end of the hydraulic plug, one end of the piston rod seals and slides and extends into the slide groove and is fixedly connected to one end of the elastic pin; The top end of the fixed mold is detachably mounted with an inlay block by means of bolts, and the inlay block is engaged with the fixed mold to form a vacuum guide groove and a pressure chamber.

5. A die-casting method for producing an engine front cover, using the vacuum die-casting equipment according to any one of claims 1 to 4, characterized in that: The specific steps are: First, the movable mold is slid and closed with the fixed mold to form a closed cavity between the fixed mold and the movable mold. Then, a vacuum pump is used to evacuate the closed cavity through the connecting nozzle and the vacuum guide groove. Then, the molten metal is injected into the closed cavity through the injection assembly. During the process of injecting molten metal into the mold cavity, the vacuum pump continuously evacuates the mold cavity. At the same time, the injection component drives the ejection component through the transmission component to accumulate force, and when the mold cavity is about to be filled with molten metal, the locking component is driven by the transmission component to release the limit on the ejection component. At this time, the ejection component drives the sealing plug to eject upward rapidly, so that the sealing plug is quickly sealed and connected to the sealing groove, closing and sealing the vacuum guide groove.

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