A special protective atmosphere and ultra-high negative pressure precision casting mold shell vacuum pouring device

Abstract

The present application belongs to the technical field of shell pouring equipment, and particularly relates to a special protective atmosphere and ultra-high negative pressure precision casting shell vacuum pouring device, which comprises a bottom plate, a pouring seat is arranged above the bottom plate, the bottom plate and the pouring seat are elastically connected through a plurality of first springs, a plurality of guide rods are fixedly connected to the upper end of the pouring seat, a top plate is fixedly connected to the top end of the plurality of guide rods, and a moving plate is slidingly connected to the plurality of guide rods. The present application is provided with a multi-dimensional vibration mechanism, which is combined with'reciprocal screw rod driving horizontal reciprocating motion + rotating ring driving circumferential rotating motion + electromagnetic vibrator vertical vibration' to construct a three-dimensional composite vibration field. The vibration field can break the metal liquid flow resistance from X, Y and Z directions, especially for thin-walled, deep-cavity and complex structure castings, and can effectively promote the metal liquid to uniformly fill into each corner of the cavity, thereby avoiding the problems of local lack of meat and uneven structure.

Description

Technical Field

[0001] This invention belongs to the technical field of mold casting equipment, and in particular relates to a vacuum casting device for precision casting molds under special protective atmosphere and ultra-high negative pressure. Background Technology

[0002] In the field of precision casting, the forming quality of the mold shell directly determines the mechanical properties, dimensional accuracy, and surface finish of the casting. This is especially true for complex structural castings made of high-performance materials such as high-temperature alloys and titanium alloys, where the requirements for atmosphere control and pressure stability in the casting environment are extremely stringent. Traditional mold shell casting equipment generally suffers from two major pain points:

[0003] First, there is a lack of control over the protective atmosphere and insufficient stability of the negative pressure. Existing equipment mostly adopts an open or simple sealed structure, which cannot create a continuous and pure special protective atmosphere (such as an inert gas protective atmosphere). This leads to oxidation of the molten metal when it comes into contact with air during high-temperature casting, resulting in oxide inclusion defects. At the same time, conventional negative pressure systems have low vacuum efficiency and poor sealing performance, making it difficult to maintain an ultra-high negative pressure environment above -0.09MPa. When the molten metal is filling the cavity, it is prone to porosity and shrinkage due to insufficient pressure gradient. This problem is particularly prominent for thin-walled and deep-cavity castings.

[0004] Secondly, the casting process is prone to clogging, and the vibration-assisted effect is limited. Traditional casting pipes are mostly cylindrical structures, which easily lead to accumulation and clogging inside the pipe when used with high-viscosity molten metal or composite raw materials containing particulate reinforcing phases. Furthermore, existing vibration mechanisms mostly vibrate in a single direction (such as vertical), failing to create a three-dimensional composite vibration field. This results in high flow resistance of the molten metal within the mold cavity, making it difficult to uniformly fill the micro-cavities and causing defects such as localized missing material and uneven microstructure in the casting. In addition, existing devices lack an emergency protection mechanism for abnormal negative pressure. When the vacuum level suddenly drops, the mold shell is prone to deformation or even rupture due to excessive internal and external negative pressure differences, resulting in casting scrap and equipment damage.

[0005] To address the aforementioned issues, there is an urgent need to develop a precision casting mold vacuum casting device with special protective atmosphere maintenance function, ultra-high negative pressure stable control, multi-dimensional vibration-assisted filling, and multiple anti-clogging and emergency protection features to meet the mass production needs of high-performance precision castings. Summary of the Invention

[0006] The purpose of this invention is to address the problems mentioned in the background art by providing a vacuum casting device for precision casting mold shells with special protective atmosphere and ultra-high negative pressure, which features special protective atmosphere maintenance, ultra-high negative pressure stable control, multi-dimensional vibration-assisted filling, and multiple anti-clogging and emergency protection functions.

[0007] To achieve the above objectives, the present invention adopts the following technical solutions:

[0008] A special protective atmosphere and ultra-high negative pressure precision casting mold shell vacuum pouring device includes:

[0009] A base plate is provided above the base plate. The base plate and the casting seat are elastically connected by a number of first springs. A number of guide rods are fixedly connected to the upper end of the casting seat. A top plate is fixedly connected to the top end of the multiple guide rods. A movable plate is slidably connected through the multiple guide rods. A hydraulic rod is fixedly connected to the upper end of the top plate. The output end of the hydraulic rod is fixedly connected to the movable plate.

[0010] A multidimensional vibration mechanism is used to apply "three-dimensional composite vibration" to the casting seat during the casting process. The multidimensional vibration mechanism includes a rotating ring rotatably connected to the upper end of a base plate. A reciprocating screw is rotatably connected between the inner walls of the two sides of the rotating ring. A first motor for driving the reciprocating screw is fixedly connected inside the rotating ring. A moving block is threaded onto the reciprocating screw. A connecting rod is fixedly connected to the upper end of the moving block. An electromagnetic vibrator that contacts the bottom end of the casting seat is fixedly connected to the top end of the connecting rod. An extension block is fixedly connected to one side wall of the base plate. A drive assembly for driving the rotating ring is fixedly connected to the extension block.

[0011] The inner walls of the two sides of the rotating ring are fixedly connected to symmetrically distributed limiting rods on both sides of the reciprocating screw, and the moving block is slidably connected to the limiting rods.

[0012] Preferably, the lower end of the movable plate is fixedly connected to an upper mold, the casting seat is provided with a lower mold, and the top plate is fixedly connected to a casting pipe for pouring raw materials into the upper and lower molds.

[0013] Preferably, the rotating ring is provided with two symmetrically distributed pressurizing mechanisms to prevent the raw material from clogging in the casting pipe during vibration. The pressurizing mechanism includes an elastic arc plate fixedly connected to the inner wall of the rotating ring. The side of the moving block near the elastic arc plate is rotatably connected to a push wheel via an extension rod. The elastic arc plate always tends to bend towards the reciprocating screw in its initial state. An elastic airbag is fixedly connected between the elastic arc plate and the inner wall of the rotating ring. An air inlet is fixedly connected to the upper end of the elastic airbag. A circular air storage box is fixedly connected to the lower end of the base plate. The elastic airbag and the circular air storage box are sealed and rotatably connected. A pressurizing pipe is fixedly connected to one side wall of the circular air storage box. The other end of the pressurizing pipe extends into the casting pipe.

[0014] Preferably, both the air inlet and the pressurization pipe are equipped with one-way valves.

[0015] Preferably, the drive assembly includes a drive rod rotatably connected to the upper end of the extension block, a drive gear fixedly connected to the drive rod, an annular toothed groove meshing with the drive gear on the circumferential sidewall of the rotating ring, and a second motor for driving the drive rod fixedly connected to the lower end of the extension block.

[0016] Preferably, the upper end of the drive rod is provided with an impact mechanism for applying vibration to the side wall of the pouring pipe during the pouring process to further prevent raw material blockage. The impact mechanism includes a drive ring fixedly connected to the upper end of the drive rod. Multiple first magnetic sheets arranged in a circular array are fixedly connected to the peripheral side wall of the drive ring. A moving rod is slidably connected to the upper end of the top plate in the horizontal direction. A transmission block is fixedly connected to the upper end of the moving rod. A second magnetic sheet is fixedly connected to the side wall of the transmission block near the drive ring. When the first magnetic sheet and the second magnetic sheet are facing each other, opposite poles attract each other. An impact block is fixedly connected to the end of the transmission block near the pouring pipe. A fixed block is fixedly connected to the upper end of the top plate. A second spring is provided between the moving rod and the fixed block.

[0017] Preferably, a suction pipe is fixedly connected to the upper end of the movable plate, an emergency pipe is fixedly connected to the suction pipe, a pneumatic shut-off valve is provided on the casting pipe, and an emergency air supply valve is provided on the suction pipe.

[0018] Preferably, the inner wall of the upper mold is embedded with three sets of vacuum pressure switches. When any one set of switches detects that the vacuum level is lower than the threshold, the external control system immediately triggers "double insurance": closes the pneumatic shut-off valve on the pouring pipe to stop pouring; and opens the emergency air supply valve of the suction pipe bypass to prevent the mold shell from deforming due to negative pressure difference.

[0019] Compared with existing technologies, the advantages of this special protective atmosphere and ultra-high negative pressure precision casting mold shell vacuum pouring device are as follows:

[0020] 1. This invention, through the linkage of a suction pipe with an external vacuum system and an inert gas supply system, can rapidly construct and maintain an ultra-high negative pressure environment above -0.09 MPa within the mold cavity after mold closing. Simultaneously, inert gases (such as argon or nitrogen) are injected into the cavity through a special protective atmosphere supply channel, forming a stable special protective atmosphere. On one hand, the ultra-high negative pressure environment can reduce the flow resistance of molten metal, promoting its full filling of micro-cavities and reducing porosity and shrinkage defects. On the other hand, the special protective atmosphere can isolate air, preventing oxidation of the high-temperature molten metal, reducing the content of oxide inclusions, and significantly improving the mechanical properties and surface quality of the casting. It is especially suitable for the precision casting of easily oxidized materials such as high-temperature alloys and titanium alloys.

[0021] 2. This invention constructs a three-dimensional composite vibration field by setting up a multi-dimensional vibration mechanism, combining "reciprocating screw driving horizontal reciprocating motion + rotating ring driving circular rotation motion + electromagnetic vibrator vertical vibration". This vibration field can break the flow resistance of molten metal in the X, Y, and Z directions, especially for thin-walled, deep-cavity, and complex-structure castings. It can effectively promote the uniform filling of molten metal into all corners of the cavity, avoiding problems such as local missing material and uneven structure. At the same time, the vibration can promote the floating and expulsion of air bubbles in the molten metal, further improving the density of the casting. Compared with traditional single-direction vibration, the casting qualification rate can be increased by more than 30%.

[0022] 3. This invention employs a pressurization mechanism that utilizes the reciprocating motion of a moving block to drive an elastic airbag in a "compression-expansion" manner, continuously injecting high-pressure gas into the casting pipe. Combined with the tapered structure of the casting pipe and the spiral guide vanes, this creates a downward thrust on the molten metal, preventing blockage. Simultaneously, an impact mechanism, through magnetic attraction and spring reset, drives an impact block to apply 5-10Hz high-frequency micro-vibrations to the sidewall of the casting pipe, breaking the adhesion tendency of the molten metal to the pipe wall and preventing scaling and blockage by viscous materials. This dual anti-blocking mechanism ensures stable casting of high-viscosity, particulate-containing materials, reducing the blockage rate by over 90% compared to traditional devices and significantly improving production efficiency.

[0023] 4. This invention embeds three sets of vacuum pressure switches into the inner wall of the upper mold to monitor the ultra-high negative pressure state inside the cavity in real time. When any set of switches detects that the vacuum level is lower than the threshold, the external control system immediately triggers a "double insurance": first, it closes the pneumatic shut-off valve of the pouring pipe to stop the injection of raw materials and avoid filling defects caused by insufficient vacuum; second, it opens the emergency air supply valve of the suction pipe to balance the air pressure inside and outside the mold shell and prevent the mold shell from deforming and cracking due to excessive negative pressure difference. This mechanism can quickly respond to abnormal negative pressure, effectively reduce equipment failure rate and casting scrap rate, and improve the safety and stability of the production process. Attached Figure Description

[0024] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0025] Figure 2 yes Figure 1 Enlarged view of point A in the middle;

[0026] Figure 3 yes Figure 1 Enlarged view of point B in the middle;

[0027] Figure 4 This is a three-dimensional structural schematic diagram of the present invention from another angle;

[0028] Figure 5 This is a partial structural diagram of the rotating ring in this invention.

[0029] In the picture:

[0030] 1. Base plate; 11. Casting seat; 12. First spring; 13. Guide rod; 14. Top plate; 15. Moving plate; 16. Upper mold; 17. Lower mold; 18. Casting pipe;

[0031] 2. Multidimensional vibration mechanism; 21. Rotating ring; 22. Reciprocating lead screw; 23. Moving block; 24. Connecting rod; 25. Extension block; 26. Drive assembly; 261. Drive rod; 262. Drive gear; 263. Annular toothed groove; 264. Second motor;

[0032] 3. Limit rod;

[0033] 4. Pressurization mechanism; 41. Elastic arc plate; 42. Push wheel; 43. Elastic airbag; 44. Air inlet; 45. Circular air tank; 46. Pressurization pipe;

[0034] 5. Impact mechanism; 51. Drive ring; 52. First magnetic plate; 53. Moving rod; 54. Transmission block; 55. Second magnetic plate; 56. Impact block; 57. Second spring;

[0035] 6. Suction tube; 61. Emergency tube. Detailed Implementation

[0036] The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0037] Example: Refer to Figures 1 to 5 A special protective atmosphere and ultra-high negative pressure precision casting mold shell vacuum pouring device, comprising:

[0038] A base plate 1 is provided, and a casting seat 11 is provided above the base plate 1. The base plate 1 and the casting seat 11 are elastically connected by a number of first springs 12. A number of guide rods 13 are fixedly connected to the upper end of the casting seat 11. A top plate 14 is fixedly connected to the top end of the multiple guide rods 13. A movable plate 15 is slidably connected through the multiple guide rods 13. A hydraulic rod is fixedly connected to the upper end of the top plate 14. The output end of the hydraulic rod is fixedly connected to the movable plate 15.

[0039] Specifically, the lower end of the movable plate 15 is fixedly connected to the upper mold 16, the pouring seat 11 is provided with the lower mold 17, and the top plate 14 is fixedly connected to the pouring pipe 18 for pouring raw materials into the upper mold 16 and the lower mold 17.

[0040] Before pouring, the assembly and initial debugging of the device must be completed to ensure that all components are ready for operation. First, the lower mold 17 is precisely fixed in the preset slot of the pouring seat 11. The moving plate 15 is driven by the hydraulic rod at the upper end of the top plate 14 to slide vertically downward along the guide rod 13 until the upper mold 16 and the lower mold 17 at the lower end of the moving plate 15 are completely closed, forming a sealed pouring cavity. At this time, the connection and sealing between the suction pipe 6 and the external vacuum system are checked. The cavity after mold closing is evacuated through the suction pipe 6 to create an ultra-high negative pressure environment (the initial vacuum degree must reach above -0.09MPa). At the same time, the pneumatic shut-off valve on the pouring pipe 18 and the emergency air supply valve on the suction pipe 6 are closed to prepare for subsequent pouring.

[0041] During this process, several first springs 12 between the base plate 1 and the casting seat 11 are in a natural extension and contraction state, which not only provides stable support for the casting seat 11, but also cooperates with the multi-dimensional vibration mechanism 2 to achieve vertical vibration buffering during subsequent vibration, so as to avoid damage to the mold or casting seat 11 caused by rigid connection.

[0042] The multidimensional vibration mechanism 2 is used to apply "three-dimensional composite vibration" to the casting seat 11 during the casting process. The multidimensional vibration mechanism 2 includes a rotating ring 21 rotatably connected to the upper end of the base plate 1. A reciprocating screw 22 is rotatably connected between the inner walls of the two sides of the rotating ring 21. A first motor for driving the reciprocating screw 22 is fixedly connected inside the rotating ring 21. A moving block 23 is threadedly connected to the reciprocating screw 22. A connecting rod 24 is fixedly connected to the upper end of the moving block 23. An electromagnetic vibrator that contacts the bottom end of the casting seat 11 is fixedly connected to the top end of the connecting rod 24. An extension block 25 is fixedly connected to one side wall of the base plate 1. A drive assembly 26 for driving the rotating ring 21 is fixedly connected to the extension block 25.

[0043] Limiting rods 3, symmetrically distributed on both sides of the reciprocating screw 22, are fixedly connected between the inner walls of the two sides of the rotating ring 21, and the moving block 23 is slidably connected to the limiting rods 3.

[0044] After the device completes the initial vacuum preparation, the multi-dimensional vibration mechanism 2 is activated to provide three-dimensional composite vibration power for the material filling during the casting process. The specific operation is as follows:

[0045] Vertical vibration start-up: The first motor fixed inside the rotating ring 21 is activated, driving the reciprocating screw 22 to rotate around its own axis. Since the moving block 23 is threadedly connected to the reciprocating screw 22, and the moving block 23 is slidably connected to the limiting rods 3 on both sides of the reciprocating screw 22, the rotation of the reciprocating screw 22 is converted into the horizontal reciprocating motion of the moving block 23 along the limiting rods 3. At the same time, the electromagnetic vibrator connected to the upper end of the moving block 23 through the connecting rod 24 continues to work, applying a vertical vibration force to the bottom end of the casting seat 11. This vibration is transmitted through the casting seat 11 to the mold cavity after mold closing, providing vertical power for material filling.

[0046] Synthesis of horizontal vibration and three-dimensional composite vibration: The second motor 264 at the lower end of the extension block 25 is activated. The second motor 264 drives the drive rod 261 to rotate around its own axis, and the drive gear 262 on the drive rod 261 rotates accordingly. Since the drive gear 262 meshes with the annular tooth groove 263 on the side wall of the rotating ring 21, the rotation of the drive gear 262 will drive the rotating ring 21 to rotate slowly around the central axis of the base plate 1 (the speed can be adjusted according to the characteristics of the casting material, usually controlled at 5-10 r / min). The rotation of the rotating ring 21 will drive the reciprocating screw, the moving block 23 and the electromagnetic vibrator to rotate synchronously around the central axis, so that the vertical vibration direction applied by the electromagnetic vibrator changes continuously with the rotation of the rotating ring 21, and finally forms a three-dimensional composite vibration effect of "X-axis horizontal reciprocating + Y-axis rotational offset + Z-axis vertical vibration" with the horizontal reciprocating motion of the moving block 23.

[0047] The core function of three-dimensional composite vibration is to break the flow resistance of raw materials in the negative pressure cavity. Especially for high viscosity or granular casting materials, it can effectively prevent the accumulation of raw materials and the formation of voids, ensuring that the raw materials are evenly filled to every corner of the cavity, thereby improving the molding accuracy and density of the casting.

[0048] Two symmetrically distributed pressurizing mechanisms 4 are provided inside the rotating ring 21 to prevent the raw material from being blocked in the pouring pipe 18 during vibration. The pressurizing mechanism 4 includes an elastic arc plate 41 fixedly connected to the inner wall of the rotating ring 21. The side of the moving block 23 near the elastic arc plate 41 is rotatably connected to the push wheel 42 through the extension rod. In the initial state, the elastic arc plate 41 always has a tendency to bend towards the reciprocating screw 22. An elastic air bladder 43 is fixedly connected between the elastic arc plate 41 and the inner wall of the rotating ring 21. An air inlet 44 is fixedly connected to the upper end of the elastic air bladder 43. A circular air storage box 45 is fixedly connected to the lower end of the bottom plate 1. The elastic air bladder 43 and the circular air storage box 45 are sealed and rotatably connected. A pressurizing pipe 46 is fixedly connected to one side wall of the circular air storage box 45. The other end of the pressurizing pipe 46 extends into the pouring pipe 18.

[0049] Specifically, both the air inlet 44 and the pressurization pipe 46 are equipped with one-way valves.

[0050] While the multi-dimensional vibration mechanism 2 is working, the two symmetrical pressurizing mechanisms 4 inside the rotating ring 21 are started simultaneously, providing continuous pressurization to the casting pipe 18 through air pressure linkage to prevent the raw material from clogging inside the pipe. The specific process is as follows:

[0051] Inflation process of the elastic airbag: When the moving block 23 reciprocates horizontally along the limiting rod 3, the extension rod of the moving block 23 near the elastic arc plate 41 drives the push wheel 42 to move synchronously. Since the elastic arc plate 41 always tends to bend towards the reciprocating screw 22 in its initial state, the push wheel 42 exerts a squeezing force on the elastic arc plate 41 as the moving block 23 moves closer to it, forcing the elastic arc plate 41 to deform away from the reciprocating screw 22, thereby compressing the elastic airbag 43 between the elastic arc plate 41 and the inner wall of the rotating ring 21. When the moving block 23 drives the push wheel 42 away from the elastic arc plate 41, the elastic arc plate 41 returns to its original position under the action of its own elastic restoring force, and the elastic airbag 43 expands accordingly. At this time, the elastic airbag 43 draws in air from the outside through the air inlet 44 at the upper end (the one-way valve in the air inlet 44 ensures that air can only enter the airbag in one direction).

[0052] Air pressure transmission and pouring pipe pressurization: Under the reciprocating drive of the moving block 23, the elastic airbag 43 continuously completes the "compression-expansion" cycle, continuously pressing outside air into the circular air storage box 45, which is sealed and rotated in communication with the elastic airbag 43. The air pressure in the circular air storage box 45 gradually increases, and the high-pressure air is transmitted to the pouring pipe 18 through the pressurization pipe 46 on the side wall of the circular air storage box 45 (the one-way valve in the pressurization pipe 46 ensures that the high-pressure air can only enter the pouring pipe in one direction). At this time, the pneumatic shut-off valve on the pouring pipe 18 is opened, and the pouring material is injected from the upper end of the pouring pipe 18. The high-pressure air in the pipe will generate a downward thrust on the material. Combined with the pouring pipe 18's own "gradually narrowing guide pipe (inlet diameter 50mm, outlet diameter 30mm, taper 15°)" structure and the spiral guide vane (lead 20mm) inside the pipe, the material is guided spirally downward, avoiding the accumulation of particulate material in the pipe, and fundamentally solving the problem of pouring pipe blockage.

[0053] The drive assembly 26 includes a drive rod 261 rotatably connected to the upper end of the extension block 25, a drive gear 262 fixedly connected to the drive rod 261, an annular tooth groove 263 meshing with the drive gear 262 on the peripheral side wall of the rotating ring 21, and a second motor 264 for driving the drive rod 261 fixedly connected to the lower end of the extension block 25.

[0054] The upper end of the drive rod 261 is provided with an impact mechanism 5, which is used to apply vibration to the side wall of the pouring pipe 18 during the pouring process to further prevent the raw material from clogging. The impact mechanism 5 includes a drive ring 51 fixedly connected to the upper end of the drive rod 261. Multiple first magnetic sheets 52 distributed in a circular array are fixedly connected to the peripheral side wall of the drive ring 51. The upper end of the top plate 14 is slidably connected to a moving rod 53 in the horizontal direction. The upper end of the moving rod 53 is fixedly connected to a transmission block 54. A second magnetic sheet 55 is fixedly connected to the side wall of the transmission block 54 near the drive ring 51. When the first magnetic sheet 52 and the second magnetic sheet 55 are facing each other, opposite poles attract each other. An impact block 56 is fixedly connected to the end of the transmission block 54 near the pouring pipe 18. A fixed block is fixedly connected to the upper end of the top plate 14. A second spring 57 is provided between the moving rod 53 and the fixed block.

[0055] To further enhance the anti-clogging effect, the impact mechanism 5 at the upper end of the drive rod 261 is linked with the pressurization mechanism 4 to apply impact to the side wall of the casting pipe 18 through high-frequency micro-vibration. The specific working process is as follows:

[0056] Magnetic plate linkage and moving rod drive: When the second motor 264 drives the driving rod 261 to rotate, the driving ring 51 at the upper end of the driving rod 261 rotates synchronously, and the multiple circumferential array of first magnetic plates 52 on the side wall of the driving ring 51 rotates around the axis of the driving rod 261. When a certain first magnetic plate 52 rotates to be directly opposite the second magnetic plate 55 on the transmission block 54, the opposite poles of the first magnetic plate 52 and the second magnetic plate 55 attract each other, generating a magnetic force that drives the transmission block 54 to move closer to the driving ring 51 in the horizontal direction at the upper end of the top plate 14. At the same time, the moving rod 53 at the lower end of the transmission block 54 moves synchronously, stretching the second spring 57 between the moving rod 53 and the fixed block.

[0057] High-frequency impact of the impact block: When the drive ring 51 continues to rotate, the first magnetic plate 52 and the second magnetic plate 55 are misaligned, and the attraction between them disappears. The second spring 57 contracts rapidly under its own elastic restoring force, pulling the moving rod 53 and the transmission block 54 back to the direction of the casting pipe 18. The impact block 56 near the end of the transmission block 54 close to the casting pipe 18 then impacts the side wall of the casting pipe 18. As the drive ring 51 continues to rotate, the impact block 56 will perform high-frequency micro-vibration impact on the casting pipe 18 at a frequency of 5-10Hz. This vibration can break the adhesion tendency of the raw material on the inner wall of the casting pipe. Especially for raw materials with high viscosity, it can effectively prevent them from forming scale or blockage on the pipe wall. Together with the pressurizing mechanism 4, it forms a dual anti-blocking guarantee of "pneumatic thrust + high-frequency micro-vibration".

[0058] The upper end of the movable plate 15 is fixedly connected to a suction pipe 6, and an emergency pipe 61 is fixedly connected to the suction pipe 6. A pneumatic shut-off valve is provided on the casting pipe 18, and an emergency air supply valve is provided on the suction pipe 6.

[0059] Three sets of vacuum pressure switches are embedded in the inner wall of the upper mold 16. When any one of the switches detects that the vacuum level is lower than the threshold, the external control system immediately triggers "double insurance": closes the pneumatic shut-off valve on the pouring pipe 18 to stop pouring; and opens the emergency air supply valve bypassing the suction pipe 6 to prevent the mold shell from deforming due to negative pressure difference.

[0060] Throughout the casting process, three sets of vacuum pressure switches embedded in the inner wall of the upper mold 16 monitor the vacuum level inside the cavity in real time. When any one set of switches detects that the vacuum level is lower than the set threshold (-0.09MPa), the external control system immediately triggers a "double insurance" emergency mechanism, as follows:

[0061] First layer of protection: Stop pouring: The control system sends a closing signal to the pneumatic shut-off valve on the pouring pipe 18. The pneumatic shut-off valve quickly cuts off the raw material channel of the pouring pipe 18, stops the injection of raw materials, and avoids uneven filling of raw materials or the formation of air bubbles due to insufficient vacuum.

[0062] Second layer of protection: emergency air replenishment: At the same time, the control system sends an opening signal to the emergency air replenishment valve on the suction pipe 6. The emergency air replenishment valve opens, and outside air slowly enters the cavity through the emergency pipe 61 bypassed by the suction pipe 6, balancing the air pressure difference between the inside and outside of the cavity, and preventing the cavity from deforming or cracking due to pressure imbalance inside and outside the mold shell caused by excessively low negative pressure.

[0063] After the staff has investigated and repaired the cause of the vacuum drop (such as damaged seals or leaks in the suction pipe), the emergency air supply valve is closed, and the vacuum is re-evacuated through the suction pipe to the 6 cavities to above the threshold. Only then can the pneumatic shut-off valve be opened again to continue the casting operation, ensuring the safety of the entire casting process and the stability of the casting quality.

[0064] The functional principle of this invention can be explained through the following operational methods:

[0065] Initial preparation: First, fix the lower mold 17 in the slot of the pouring seat 11. Activate the hydraulic rod on the top plate 14 to drive the moving plate 15 downwards along the guide rod 13, so that the upper mold 16 and the lower mold 17 can be precisely closed. Next, connect the external vacuum system through the suction pipe 6 to evacuate the cavity after mold closing until the vacuum level reaches above -0.09MPa. Then, close the pneumatic shut-off valve of the pouring pipe 18 and the emergency air supply valve of the suction pipe 6 to complete the preparation before pouring.

[0066] Multidimensional vibration and casting start-up operation: The multidimensional vibration mechanism 2 is activated. The first motor drives the reciprocating screw 22 to rotate, causing the moving block 23 to reciprocate horizontally along the limit rod 3. The electromagnetic vibrator at its upper end applies vertical vibration to the casting seat 11. Simultaneously, the second motor 264 drives the drive rod 261 to rotate. Through the drive gear 262 meshing with the annular tooth groove 263, the rotating ring 21 rotates, causing the vibration direction of the electromagnetic vibrator to change with the rotating ring 21, forming a three-dimensional composite vibration. Then, the pneumatic shut-off valve of the casting pipe 18 is opened, and the raw material is injected into the cavity through the casting pipe 18. The three-dimensional composite vibration helps to uniformly fill the raw material.

[0067] Anti-clogging linkage operation: When the moving block 23 reciprocates, the push wheel 42 squeezes the elastic arc plate 41, causing the elastic air bag 43 to compress and exhaust gas into the circular air storage box 45. The high-pressure gas enters the pouring pipe 18 through the pressurization pipe 46. With the gradual contraction structure and spiral guide plate of the pouring pipe 18, the raw material is prevented from clogging. At the same time, the drive rod 261 drives the drive ring 51 to rotate. The first magnetic plate 52 and the second magnetic plate 55 alternately attract and separate. The second spring 57 drives the impact block 56 to impact the pouring pipe 18 at high frequency, further avoiding the adhesion and clogging of raw materials.

[0068] Negative pressure safety protection operation: Three sets of vacuum pressure switches on the inner wall of the upper mold 16 monitor the vacuum degree of the cavity in real time. If any set detects that the vacuum degree is lower than -0.09MPa, the external control system immediately closes the pneumatic shut-off valve of the pouring pipe 18 to stop pouring, and at the same time opens the emergency air supply valve of the suction pipe 6 to balance the air pressure inside and outside the cavity and prevent the mold shell from deforming.

[0069] Molding and part removal operation: After the raw material is filled, the multi-dimensional vibration mechanism 2, the pressurizing mechanism 4 and the impact mechanism 5 are turned off, and the negative pressure in the cavity is maintained until the raw material solidifies. Then, air is slowly replenished through the suction pipe 6 until the air pressure inside and outside the cavity is balanced. The hydraulic rod is started to move the moving plate 15 upward to open the upper mold 16. Finally, the molded casting in the lower mold 17 is taken out.

[0070] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A special protective atmosphere and ultra-high negative pressure precision casting mold shell vacuum pouring device, characterized in that, The utility model relates to a three -dimensional compound vibration casting device, including: The bottom plate (1) is provided with pouring seat (11) upside, the bottom plate (1) and pouring seat (11) are elastically connected through a plurality of first spring (12) between, the upper end of pouring seat (11) is fixedly connected with a plurality of guide rod (13), a plurality of the top of guide rod (13) is fixedly connected with top plate (14), a plurality of guide rod (13) is slidably connected with moving plate (15) on, the upper end of top plate (14) is fixedly connected with hydraulic rod, and the output end of hydraulic rod is fixedly connected with moving plate (15); Multi -dimensional vibration mechanism (2) is used for exerting " three -dimensional compound vibration " to pouring seat (11) during pouring, and multi -dimensional vibration mechanism (2) includes rotation ring (21) rotationally connected on the upper end of bottom plate (1), reciprocating screw rod (22) is rotationally connected between the inner wall of both sides of rotation ring (21), and the first motor for driving reciprocating screw rod (22) is fixedly connected in rotation ring (21), and moving block (23) is threadedly connected on reciprocating screw rod (22), and the upper end of moving block (23) is fixedly connected with connecting rod (24), and the top of connecting rod (24) is fixedly connected with electromagnetic vibrator in contact with the bottom end of pouring seat (11), and the side wall of bottom plate (1) is fixedly connected with extension block (25), and the extension block (25) is fixedly connected with drive assembly (26) for driving rotation ring (21) on, The inner wall of both sides of rotation ring (21) is fixedly connected with limit rod (3) that is symmetrically distributed in the both sides of reciprocating screw rod (22), and moving block (23) is slidably connected in limit rod (3); The inner wall of both sides of rotation ring (21) is fixedly connected with limit rod (3) that is symmetrically distributed in the both sides of reciprocating screw rod (22), and moving block (23) is slidably connected in limit rod (3); 2. The special protected atmosphere and ultra-high negative pressure precision casting mold shell vacuum pouring device according to claim 1, characterized in that, The rotation ring (21) is provided with two symmetrically distributed pressure mechanisms (4) inside, for avoiding the blocking of raw materials in the pouring pipe (18) during the vibration, the pressure mechanism (4) includes the elastic arc plate (41) fixedly connected to the inner wall of the rotation ring (21), the side of the moving block (23) close to the elastic arc plate (41) is rotationally connected with the push wheel (42) through the extension rod, the elastic arc plate (41) always has a bending trend to the side of the reciprocating screw rod (22) in the initial state, the elastic arc plate (41) and the inner wall of the rotation ring (21) are fixedly connected with the elastic air bag (43), the upper end of the elastic air bag (43) is fixedly connected with the air inlet (44), the lower end of the bottom plate (1) is fixedly connected with the circular gas storage tank (45), the elastic air bag (43) and the circular gas storage tank (45) are sealingly and rotationally connected, one side wall of the circular gas storage tank (45) is fixedly connected with the pressure pipe (46), the other end of the pressure pipe (46) extends into the pouring pipe (18).

3. The special protected atmosphere and ultra-high negative pressure precision casting mold shell vacuum pouring device according to claim 1, characterized in that, The lower end of the moving plate (15) is fixedly connected with the upper mold (16), the pouring seat (11) is provided with the lower mold (17) inside, and the top plate (14) is fixedly connected with the pouring pipe (18) for pouring raw materials into the upper mold (16) and the lower mold (17). The air inlet (44) and the pressure pipe (46) are provided with one-way valves.

4. The special protected atmosphere and ultra-high negative pressure precision casting mold shell vacuum pouring device according to claim 2, characterized in that, The driving assembly (26) comprises a driving rod (261) rotatably connected to the upper end of the extension block (25), a driving gear (262) is fixedly connected to the upper end of the driving rod (261), an annular tooth groove (263) is arranged on the peripheral wall of the rotating ring (21) and is in meshing connection with the driving gear (262), and the lower end of the extension block (25) is fixedly connected with a second motor (264) for driving the driving rod (261).

5. The special protected atmosphere and ultra-high negative pressure precision casting mold shell vacuum pouring device according to claim 4, characterized in that, The upper end of the driving rod (261) is provided with an impact mechanism (5) for applying vibration to the sidewall of the pouring pipe (18) during pouring to further prevent the raw material from being blocked, the impact mechanism (5) comprises a driving ring (51) fixedly connected to the upper end of the driving rod (261), a plurality of first magnetic sheets (52) arranged in a circumferential array are fixedly connected to the peripheral wall of the driving ring (51), a moving rod (53) is slidingly connected to the upper end of the top plate (14) in the horizontal direction, a transmission block (54) is fixedly connected to the upper end of the moving rod (53), a second magnetic sheet (55) is fixedly connected to one side wall of the transmission block (54) close to the driving ring (51), the first magnetic sheet (52) and the second magnetic sheet (55) are attracted to each other when they face each other, the transmission block (54) is fixedly connected with an impact block (56) at one end close to the pouring pipe (18), the upper end of the top plate (14) is fixedly connected with a fixed block, and the moving rod (53) and the fixed block are provided with a second spring (57) therebetween.

6. The special protected atmosphere and ultra-high negative pressure precision casting mold shell vacuum pouring device according to claim 2, characterized in that, The upper end of the moving plate (15) is fixedly connected with a suction pipe (6), the suction pipe (6) is fixedly connected with an emergency pipe (61), the pouring pipe (18) is provided with a pneumatic stop valve, and the suction pipe (6) is provided with an emergency air supplement valve.

7. The special protected atmosphere and ultra-high underpressure precision casting mold shell vacuum pouring device according to claim 6, characterized in that, The inner wall of the upper mold (16) is embedded with three groups of vacuum pressure switches, when any one group of switches detects that the vacuum degree is lower than the threshold value, the external control system immediately triggers "double insurance": the pneumatic stop valve on the pouring pipe (18) is closed to stop pouring, and the emergency air supplement valve bypassing the suction pipe (6) is opened to avoid deformation of the mold shell due to negative pressure difference.

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