An automatic casting device for lost foam

Abstract

The application relates to the technical field of lost foam casting, in particular to a lost foam automatic casting device which comprises a support frame, a guide rail is laid under the support frame, a sand box is slidably arranged on the guide rail, the sand box is used for placing a model cluster, a sand shower is arranged on the support frame and located directly above the sand box, and the sand shower is used for uniformly raining and drying sand in the sand box; the sand shower comprises sliding supports which are symmetrically arranged on the two sides of the support frame, a storage box is arranged between the two sliding supports, dry sand enters the sand box, fills the gap between the sand box and the model cluster, and forms a mold. The application drives the whole storage box to horizontally reciprocate through a reciprocating screw structure, cooperates with a sand shower gear and a rack precise angle adjusting structure, can realize accurate hole conduction and flux-controllable rain type shakeout, and combines with a lower extension frame follow-up protection structure, and completely solves the problems of traditional fixed shakeout, such as concentration, local sand accumulation, sand shortage, sand leakage and shakeout deviation.

Description

Technical Field

[0001] This application relates to the technical field of lost foam casting, and in particular to an automated lost foam casting apparatus. Background Technology

[0002] Lost foam casting, also known as solid casting, is a precision, near-net-shape modern casting technology. It uses foam materials such as expandable polystyrene (EPS) to create a solid model that is identical to the final casting. When the high-temperature molten metal is poured into the mold cavity, the foam model will instantly be heated, vaporized, decomposed and disappear, and the molten metal will precisely occupy its original space. After cooling and solidification, a metal casting with the same shape and size as the foam model is obtained.

[0003] For example, a lost foam casting device with application number CN202410296427.4 uses a motor to drive a gear to rotate, periodically hooking up and suddenly releasing a vibrating plate connected to the sand box. The vibrating spring and counterweight generate a strong instantaneous vertical impact force, making the dry sand flow like a liquid, initially filling the complex space around the foam mold and reducing large gaps. At the same time, the buffer spring and buffer plate integrated on the compaction plate can provide flexible protection during extrusion, physically compressing the vibrated dry sand to ensure that the sand mold is compact and closely adheres to the mold surface.

[0004] However, in the case of automated lost foam casting, the existing technology mentioned above is used when the dry sand is in a flowing state during vibration, which reduces the friction between the model and the molding sand. If the vibration force (especially the horizontal force) is too large or the vibration time is too long, it is enough to overcome the static friction between the model and the bottom dry sand, causing the model to slide or tilt.

[0005] The pressure applied by the compaction plate decreases with increasing distance. The sand is most compacted near the compaction plate, while the sand on the other side away from the compaction plate and directly below it (especially at the bottom of the sand box) is subjected to very weak compaction.

[0006] The sand at the bottom of the sand box is furthest from the compaction plate, and the weight of the sand layer above it will exert a certain pressure on it, resulting in uneven compaction of the sand layer from top to bottom, which affects the pouring effect.

[0007] Based on this, and given the above viewpoints, there is still room for improvement in existing technologies for automated lost foam casting. Summary of the Invention

[0008] To address the technical problem of vibration causing model slippage or tipping, this application provides an automated lost foam casting device, employing the following technical solution: An automated lost foam casting device includes a support frame, a guide rail laid below the support frame, a sand box slidably mounted on the guide rail, the sand box being used to hold model clusters, and a sand sprayer located directly above the sand box on the support frame, the sand sprayer being used to evenly spray dry sand into the sand box. The sand-drenching device includes sliding supports symmetrically arranged on both sides of a support frame. A storage box is located between the two sliding supports, and the storage box is used to store dry sand and is located directly above the sand box. The storage box has a discharge port at the bottom, and a sand-sprinkling tray is installed inside the discharge port. The sand-sprinkling tray is used to guide dry sand to fall evenly into the sand box. The dry sand enters the sand box and fills the gap between the sand box and the model cluster to form a mold.

[0009] Preferably, the sand-drenching tray includes a base plate installed inside the discharge port, and the base plate has several evenly distributed discharge holes, which are used for dry sand to enter the sand box.

[0010] Preferably, a turntable is rotatably mounted on the chassis, and the turntable has through holes that correspond one-to-one with the discharge holes; An arc-shaped groove is provided on the storage box, and a lever connected to the turntable is slidably disposed in the arc-shaped groove; The end of the lever is provided with an arc-shaped rack, and the storage box is provided with a drive gear that meshes with the arc-shaped rack via a bracket.

[0011] Preferably, the sliding bracket is horizontally slidably connected to the support frame, and a rotating shaft is rotatably provided on the support frame, with a reciprocating threaded section on the rotating shaft that is threadedly connected to the sliding bracket; An extension frame is provided at the bottom of the storage bin, which allows the storage bin to be moved to maintain its alignment with the sand box.

[0012] Preferably, a casting pipe is installed on the top of the storage box, and the lower end of the casting pipe extends through the storage box to the casting port of the model cluster.

[0013] Preferably, the casting pipe has a flue gas passage inside, and an outlet connected to the flue gas passage is opened on the outside of the casting pipe.

[0014] Preferably, a membrane applicator is provided on the support frame, which is used to seal and retain the pouring port at the top of the sand box. The film applicator includes symmetrically and slidably arranged support handles on a support frame, a guide rod at the end of the support handle, and a connecting plate slidably arranged on the guide rod; A sealing ring corresponding to the sandbox is provided between the two connecting plates, and a return spring is provided between the connecting plate and the support handle.

[0015] Preferably, a heat-resistant film is provided inside the sealing ring, and a heat-insulating ring is provided inside the heat-resistant film. The lower end of the heat-insulating ring corresponds to the casting port of the model cluster, and the heat-insulating ring section corresponds to the casting pipe.

[0016] In summary, this application includes at least one of the following beneficial technical effects: 1. This invention employs a reciprocating thread structure to drive the overall horizontal reciprocating sliding of the storage box. Combined with a precise angle adjustment structure using a gear and rack for the sand-spraying disc, it achieves precise hole connection and controllable flow of rain-like sand drop. Combined with a lower extension frame with a follow-up protective structure, it completely solves the problems of concentrated, localized sand accumulation, sand shortage, sand leakage, and sand deviation inherent in traditional fixed sand drop systems. It can comprehensively and uniformly fill the sand box interior, complex cavities of foam model clusters, and gaps at edges and corners with sand, resulting in high sand filling fullness and laying a solid foundation for subsequent sand molding.

[0017] 2. This invention achieves precise alignment through a symmetrical sliding support handle, combined with a spring-adaptive clamping structure, and uses a heat-resistant membrane to completely seal the upper end of the sand box, thus completely blocking air leakage channels. It can stably establish a negative pressure environment inside the sand box under working conditions with a wet sand tray, allowing the molding sand to fully compact and solidify under negative pressure, improving the compactness, structural strength and overall stability of the sand mold, and effectively reducing the risk of box collapse and sand mold deformation.

[0018] 3. This invention combines the negative pressure sealed environment of the sand box with the built-in flue gas channel and external air outlet of the casting pipe to form a dual high-efficiency exhaust structure. During the casting process, the large amount of flue gas and reducing waste gas generated by the high-temperature pyrolysis of the foam model can be quickly and smoothly discharged along the dedicated channel, effectively releasing the internal pressure of the sand mold and eliminating common casting defects such as suffocation, air blockage, porosity, casting bulging, and molding defects. This ensures that the high-temperature molten metal fills the entire cavity, improving the molding accuracy and surface quality of the casting. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the present invention.

[0020] Figure 2 This is a schematic diagram of the structure between the support frame and the sand sprayer of the present invention.

[0021] Figure 3 This is a schematic diagram of the sand-rinsing device of the present invention.

[0022] Figure 4 This is a cross-sectional view of the sand-rinsing device of the present invention.

[0023] Figure 5 This is the present invention. Figure 4 A magnified view of part A.

[0024] Figure 6 This is a schematic diagram of the sand bath structure of the present invention.

[0025] Figure 7 This is a schematic diagram of the structure of the casting pipe of the present invention.

[0026] Figure 8This is a schematic diagram of the structure between the sandbox and the film applicator of the present invention.

[0027] Figure 9 This is a schematic diagram of the structure of the film applicator of the present invention.

[0028] Explanation of reference numerals in the attached drawings: 1. Support frame; 2. Guide rail; 3. Sand box; 4. Sand sprayer; 41. Sliding bracket; 42. Storage box; 43. Discharge port; 5. Sand spraying tray; 51. Base plate; 511. Discharge hole; 52. Turntable; 521. Through hole; 53. Arc groove; 54. Pulley; 541. Arc rack; 55. Drive gear; 56. Rotating shaft; 561. Re-threaded section; 57. Extension frame; 6. Casting pipe; 61. Flue gas passage; 62. Gas outlet; 7. Film applicator; 71. Support handle; 72. Guide rod; 73. Connecting plate; 74. Sealing ring; 75. Heat-resistant film; 76. Heat insulation ring; 77. Return spring. Detailed Implementation

[0029] The following is in conjunction with the appendix Figures 1 to 9 This application will be described in further detail.

[0030] This application discloses an automated lost foam casting device. It achieves dynamic and uniform rain-like sand filling by using a reciprocating sliding storage box in conjunction with an angle-adjustable sand-sprinkling tray. Then, a film applicator with a heat-insulating ring alignment structure is used to seal the large opening of the sand box and the porous structure of the sand-sprinkling tray, and accurately retain the casting exhaust channel. Combined with the negative pressure vacuum shaping of the sand box and the synergistic exhaust of the flue gas channel built into the casting pipe, it effectively solves the defects of air leakage, loose sand mold, and stagnant casting flue gas, and significantly improves the molding quality and production stability of lost foam castings.

[0031] Example 1:

[0032] An automated lost foam casting device includes a support frame 1, a guide rail 2 laid below the support frame 1, a sand box 3 slidably mounted on the guide rail 2, the sand box 3 being used to place model clusters, and a sand sprayer 4 located directly above the sand box 3 mounted on the support frame 1, the sand sprayer 4 being used to evenly spray dry sand into the sand box 3.

[0033] During the process, a refractory coating is first evenly applied to the outer surface of the prefabricated foam model cluster, and then dried and cured to form a dense protective layer on the model surface, which avoids sand adhesion defects in the subsequent casting process and improves the overall structural strength of the model. After the coating is cured, the model cluster is placed flat and upright inside the sand box 3 and accurately positioned to ensure that the model cluster is not skewed or offset.

[0034] The prefabricated foam model cluster is stably placed inside the sand box 3 to complete the positioning of the model. Then, the sand box 3 containing the model cluster slides horizontally along the guide rail 2 and moves to the working position directly below the sand sprayer 4.

[0035] Then, the sand sprayer 4 starts working, continuously, disperses and uniformly sprinkles dry sand into the sand box 3 through a uniform rain-like sand drop mode. The dry sand evenly covers the outer surface of the foam model cluster from top to bottom, fully filling the complex structural gaps, corner grooves and cavities inside the sand box 3. The sand drop is uniform throughout the process, without local accumulation or sand shortage. It can fully wrap and fill the model cluster, avoiding the problems of voids, gaps and uneven sand filling that exist in traditional sand filling methods. Once the amount of sand inside the sand box 3 reaches the set standard, the sand sprayer 4 stops working.

[0036] Specifically, the sand-sprinkling device 4 includes sliding supports 41 symmetrically arranged on both sides of the support frame 1. A storage box 42 is arranged between the two sliding supports 41. The storage box 42 is used to store dry sand and is located directly above the sand box 3. A discharge port 43 is provided at the lower end of the storage box 42. A sand-sprinkling tray 5 is provided inside the discharge port 43. The sand-sprinkling tray 5 is used to guide the dry sand to fall evenly into the sand box 3. The dry sand enters the sand box 3 and fills the gap between the sand box 3 and the model cluster to form a mold.

[0037] During the sand filling process, the dry sand stored inside the storage box 42 is conveyed downward through the bottom outlet 43. Through the diversion and guidance of the sand spreading pan 5, the state of concentrated accumulation of dry sand is broken, so that the dry sand falls vertically in a uniform rain-like manner, and falls into the sand box 3 positioned below at a uniform speed and in a dispersed manner. The uniformly falling dry sand can gradually fill all gaps, corners, grooves and complex cavities between the inner cavity of the sand box 3 and the coated foam model cluster, and completely wrap the model cluster, thoroughly filling all gaps, without problems such as local lack of sand, sand accumulation, voids and sand inclusions. Finally, a fully filled and evenly distributed sand mold matrix is ​​formed inside the sand box 3, providing a high-quality molding foundation for the subsequent sand mold vibration and compaction processes, and effectively improving the overall accuracy and molding quality of lost foam molding.

[0038] Among them, the sand-drenching tray 5 includes a base plate 51 set inside the discharge port 43. The base plate 51 has several evenly distributed discharge holes 511. The discharge port 43 is used for dry sand to enter the sand box 3.

[0039] A turntable 52 is rotatably mounted on the chassis 51, and the turntable 52 has through holes 521 that correspond one-to-one with the discharge holes 511. During the sand filling operation, the dry sand stored inside the storage bin 42 is collected at the sand-sprinkling tray 5 through the bottom discharge port 43. During operation, it is only necessary to drive the turntable 52 to rotate relative to the base plate 51 by a preset angle so that the through hole 521 on the turntable 52 is precisely aligned with the discharge hole 511 on the base plate 51. At this time, the hole forms a through channel, and the dry sand in the storage bin 42 can fall smoothly through the overlapping through hole 521 and discharge hole 511. Through the evenly distributed hole group on the base plate 51, the dry sand can be dispersed and fall at a uniform speed, forming a stable rain-like sand falling effect, avoiding the problems of concentrated accumulation and uneven local sand filling in traditional single-point sand falling.

[0040] The evenly falling dry sand can gradually fill all gaps, corners, grooves, and complex cavities between the inner cavity of the sandbox 3 and the coated foam model cluster, completely wrapping the model cluster and thoroughly filling all gaps without problems such as local sand shortage, sand accumulation, or sand inclusion in voids. At the same time, the overlapping area of ​​the through hole 521 and the discharge hole 511 can be changed by finely adjusting the rotation angle of the turntable 52, so as to precisely control the sand flow rate. The sand falling speed can be flexibly adjusted according to different sandbox 3 sizes and different complex structure of model clusters, adapting to the sand filling operation needs of various specifications.

[0041] Once the amount of sand filling reaches the process standard, the turntable 52 is rotated again to make the through hole 521 and the discharge hole 511 staggered and blocked, thus cutting off the falling sand and completing the sand filling operation. Finally, a fully filled and evenly distributed sand mold matrix is ​​formed inside the sand box 3, providing a high-quality molding foundation for the subsequent sand mold vibration and compaction processes, effectively improving the overall accuracy and molding quality of lost foam molding.

[0042] In addition, an arc-shaped groove 53 is provided on the side wall of the storage box 42. The arc-shaped groove 53 is opened along the rotation trajectory of the turntable 52. A lever 54 is slidably installed inside the arc-shaped groove 53. The lever 54 passes through the arc-shaped groove 53 and is fixedly connected to the turntable 52, so that the lever 54 can slide along the trajectory defined by the arc-shaped groove 53 and simultaneously drive the turntable 52 to rotate and limit the angle.

[0043] The end of the push block 54 located on the outside of the storage box 42 is fixedly equipped with an arc-shaped rack 541. The outer wall of the storage box 42 is fixed with a mounting bracket, and a drive gear 55 is rotatably mounted on the bracket. The drive gear 55 meshes with the arc-shaped rack 541. By rotating the drive gear 55, the arc-shaped rack 541 can be driven to make arc-shaped displacement movement, which in turn drives the push block 54 to slide along the arc-shaped groove 53. Finally, the turntable 52 is driven to make a small angle adjustment relative to the chassis 51, so as to realize the alignment and conduction or misalignment and blockage of the through hole 521 and the discharge hole 511, and complete the control of sand discharge on / off and sand discharge flow.

[0044] The sliding bracket 41 is slidably connected to the support frame 1 in the horizontal direction. The support frame 1 is rotatably provided with a rotating shaft 56, and the rotating shaft 56 is constructed with a reciprocating thread section 561 that is threadedly connected to the sliding bracket 41.

[0045] By rotating the shaft 56, the sliding bracket 41 can be driven to make stable horizontal reciprocating sliding along the support frame 1 by means of the reciprocating thread section 561, thereby driving the storage box 42 between the sliding brackets 41 to move synchronously as a whole, realizing the lateral reciprocating movement operation of the sand washing mechanism.

[0046] An extension frame 57 is provided at the lower end of the storage box 42. The extension frame 57 allows the storage box 42 to move while maintaining its connection with the sand box 3. The extension frame 57 is fixedly provided at the lower end of the storage box 42 and is arranged corresponding to the upper end of the sand box 3. During the horizontal back-and-forth movement of the storage box 42 with the sliding bracket 41, the extension frame 57 can move synchronously with the storage box 42. Utilizing the extended covering structure of the extension frame 57, the discharge area of ​​the storage box 42 is always kept in alignment and communication with the cavity of the sand box 3. This effectively adapts to the dynamic sliding operation of the storage box 42, ensuring that the sand drop area always covers the inside of the sand box 3. This avoids sand drop deviation, sand leakage at the edge of the sand box 3, and uneven sand filling during the moving sand filling process, ensuring the overall uniformity of dynamic rain-fed sand filling.

[0047] After the sand filling operation is completed, the inside of the sand box 3 is vacuumed to further compact and solidify the molding sand inside the sand box 3 under negative pressure, reduce the gaps between molding sand particles, improve the overall compactness and structural stability of the sand mold, and at the same time, expel most of the air in the gaps of the sand mold in advance, reducing the source of subsequent casting gas.

[0048] A casting pipe 6 is installed on the storage box 42. The lower end of the casting pipe 6 extends through the storage box 42 to the casting port of the model cluster, so that the discharge end of the casting pipe 6 is precisely aligned with the casting port of the model cluster, and the directional casting of molten metal can be directly completed.

[0049] The casting tube 6 has a flue gas channel 61 inside, and an outlet 62 connected to the flue gas channel 61 is opened on the outside of the casting tube 6. The outlet 62 and the flue gas channel 61 are interconnected, so that a through flue gas passage is formed inside the casting tube 6, which allows the flue gas generated during the casting process to be discharged smoothly to the outside.

[0050] During the casting process of molten metal, the high-temperature molten metal continuously contacts, melts, and vaporizes the foam model cluster. The pyrolysis of the model cluster generates a large amount of high-temperature flue gas and reducing gas, creating a closed, high-pressure environment inside the sand mold. A dedicated exhaust passage is formed through the flue gas channel 61 reserved inside the casting pipe 6. The flue gas generated inside the sand mold can flow upward along the casting port of the model cluster into the flue gas channel 61 of the casting pipe 6, and then rise rapidly along the flue gas channel 61, finally being discharged outward through the outlet 62 on the outside of the casting pipe 6 that connects to the flue gas channel 61.

[0051] Throughout the casting process, the internal fumes are continuously channeled to effectively release the internal air pressure of the sand mold, avoiding defects such as smoldering, porosity, casting bulging, and incomplete molding caused by the retention of fumes. This ensures that the molten metal can smoothly and completely fill the sand mold cavity, improving the casting forming accuracy and finished product quality.

[0052] The vacuum system, combined with the dual exhaust structure of the dedicated flue gas channel 61, can continuously and efficiently guide the internal flue gas throughout the casting process, effectively release the internal air pressure of the sand mold, and completely avoid defects such as smoldering, porosity, casting bulging, and molding defects caused by the inability to expel flue gas. This ensures that the molten metal can smoothly and completely fill the sand mold cavity, improving the casting forming accuracy and finished product quality.

[0053] Regarding the function of the horizontal sliding of the sand box 3, the horizontal movement of the sand box 3 enables the flow of workstations. It can enter the sand-sprinkling machine 4 to complete the entire process of filling sand, sealing, vacuuming, and pouring. After the process is completed, it can be moved out of the workstation, which facilitates demolding, mold changing, and cyclic feeding, thus realizing continuous production line production.

[0054] The horizontal sliding action of the sand sprayer 4 causes the storage box 42 and the sand spraying tray 5 to move horizontally back and forth as a whole. Combined with the rain-drop sand method, it evenly spreads and fills sand in the entire area of ​​the sand box and complex model cluster, avoiding single-point sand accumulation and local sand shortage. The lower extension frame 57 of the storage box 42 slides synchronously with the sand washing device 4, always maintaining connection with the upper opening of the sand box to prevent sand leakage and sand displacement during the sliding process.

[0055] Example 2:

[0056] Based on Example 1, the upper end of the sand box 3 adopts a large opening structure design, and a sand-sprinkling tray 5 with a porous structure is set on the upper part. When vacuuming is performed after sand sprinkling and filling, serious air leakage problems are likely to occur, making it impossible to establish a stable negative pressure inside the sand box 3, which seriously affects the compaction and forming effect of the sand mold.

[0057] To this end, a membrane applicator 7 is provided on the support frame 1. The membrane applicator 7 is used to seal and retain the pouring port at the upper end of the sand box 3. During the membrane sealing process, it avoids the pouring position of the model cluster, retains the pouring port connecting channel separately, and seals the other upper opening areas to avoid air leakage defects caused by the large opening of the sand box 3 and the porous structure of the sand tray 5, and provides a sealed condition for the subsequent negative pressure vacuuming operation of the sand box 3.

[0058] Specifically, a support handle 71 is symmetrically and slidably arranged, and a guide rod 72 is provided at the end of the support handle 71. A connecting plate 73 is slidably arranged on the guide rod 72. A sealing ring 74 corresponding to the sand box 3 is provided between the two connecting plates 73. During the sealing operation, the support handles 71 on both sides slide laterally at the same time, which drives the guide rod 72, the connecting plate 73 and the sealing ring 74 to move as a whole, and accurately moves the sealing ring 74 to the top of the sand box 3 to complete the initial alignment.

[0059] A return spring 77 is provided between the connecting plate 73 and the support handle 71. The lower end of the heat insulation ring 76 corresponds to the pouring port of the model cluster, and the section of the heat insulation ring 76 corresponds to the casting pipe 6. After the alignment is completed, the material storage box 42 moves down as a whole, and the downward pressure acts on the sealing ring 74, causing the connecting plate 73 to slide down along the guide rod 72 relative to the support handle 71 and compress the return spring 77, thereby driving the sealing ring 74 to be stably pressed and adhered to the upper opening end face of the sand box 3.

[0060] A heat-resistant membrane 75 is installed inside the sealing ring 74, and a heat insulation ring 76 is installed inside the heat-resistant membrane 75. The heat-resistant membrane 75 achieves full coverage and sealing of the large opening of the sand box 3, effectively sealing the air leakage gap caused by the open top of the sand box 3 and the porous structure of the sand bath 5, so that the inside of the sand box 3 forms a sealed cavity, which meets the sealing requirements of subsequent vacuum negative pressure operation.

[0061] The implementation principle of this invention is as follows: Step 1: Precisely transport and position the sand box 3 with the built-in foam model cluster directly below the sand spreading device 4, ensuring that the upper opening of the sand box 3 is directly aligned with the sand spreading tray 5 and the casting pipe 6 above, providing a precise positional foundation for subsequent sand filling, sealing, and pouring operations.

[0062] Step 2: Dry sand is stored inside the storage box 42. During operation, the rotating shaft 56 on the support frame 1 is driven to rotate. The reciprocating thread section 561 on the rotating shaft 56 drives the sliding brackets 41 on both sides to slide horizontally in sync, thereby moving the storage box 42 and the sand-spraying tray 5 as a whole laterally.

[0063] Simultaneously, the drive gear 55 drives the arc-shaped rack 541 and the lever 54 to slide along the arc-shaped groove 53, finely adjusting the angle of the turntable 52 so that the through hole 521 of the turntable 52 coincides with the discharge hole 511 of the chassis 51 and is connected. Dry sand falls through the evenly distributed holes in a rain-like manner, and with the lateral reciprocating movement of the storage box 42, it evenly fills the interior of the sand box 3 and the gaps between the model clusters, completing an all-round sand filling operation without dead angles. The extension frame 57 at the lower end of the storage box 42 moves synchronously with the storage box 42, always covering the upper opening of the sand box 3, avoiding sand leakage and sand deviation during the sliding sand filling process. After the sand filling is completed, the turntable 52 is finely adjusted to make the through hole 521 and the discharge hole 511 misaligned and blocked, cutting off the falling sand.

[0064] Step 3: After the sand filling is completed, start the membrane applicator 7. The support handles 71 on both sides slide horizontally in sync, driving the guide rod 72, connecting plate 73 and sealing ring 74 to move as a whole, so that the sealing ring 74 is precisely aligned above the sand box 3. Then the storage box 42 moves down as a whole, pressing down the sealing ring 74, so that the connecting plate 73 slides down along the guide rod 72 and compresses the return spring 77, so that the sealing ring 74 is tightly pressed against the upper opening of the sand box 3. The heat-resistant membrane 75 inside the sealing ring 74 seals the large opening of the sand box 3 and the porous area of ​​the sand pouring tray 5. At the same time, the heat insulation ring 76 inside the heat-resistant membrane 75 keeps the lower end aligned with the pouring port of the model cluster and the upper end precisely aligned with the casting pipe 6, while sealing the whole, retaining the pouring and venting channels separately.

[0065] Step 4: With the upper end of sand box 3 sealed and only the pouring channel remaining open, vacuum treatment is performed inside sand box 3. This effectively solves the air leakage problem caused by the large opening of sand box 3 and the porous structure of sand pouring tray 5, creating a stable negative pressure environment inside sand box 3. This promotes further compaction and shaping of the molding sand under negative pressure, reduces the gaps between molding sand particles, improves the overall strength and stability of the sand mold, and at the same time removes air from the sand layer, reducing the probability of porosity defects in subsequent casting.

[0066] Step 5: Under the negative pressure and sealed state of the sand box 3, high-temperature molten metal is injected into the pouring port of the model cluster through the casting pipe 6. The high-temperature molten metal melts and vaporizes the foam model cluster. The generated high-temperature flue gas and exhaust gas can be collected upward through the flue gas channel 61 inside the casting pipe 6 and quickly discharged outward through the air outlet 62 on the outside of the casting pipe 6. The negative pressure environment, combined with the dedicated flue gas channel 61, can realize the continuous and smooth flow of flue gas, avoid problems such as scorching, porosity, and casting defects caused by excessive air pressure inside the sand mold, and ensure that the molten metal completely fills the cavity.

[0067] Step Six: After the casting operation is completed, the negative pressure of the sand box 3 is released, the storage box 42 is raised to relieve the downward pressure on the sealing ring 74, and the connecting plate 73 rebounds upward along the guide rod 72 under the elastic force of the return spring 77, which drives the sealing ring 74 and the heat-resistant film 75 to separate from the upper surface of the sand box 3. All sliding mechanisms are reset, completing a single casting molding operation. The sand box 3 can be moved out of the work position, and the equipment enters the next round of operation cycle.

[0068] The embodiments described herein are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An automated lost foam casting device, comprising a support frame (1), a guide rail (2) laid below the support frame (1), and a sandbox (3) slidably disposed on the guide rail (2) for placing model clusters, characterized in that: A sand sprayer (4) is installed on the support frame (1) and located directly above the sand box (3). The sand sprayer (4) is used to evenly spray dry sand into the sand box (3). The sand rinsing device (4) includes sliding brackets (41) symmetrically arranged on both sides of the support frame (1), and a storage box (42) is arranged between the two sliding brackets (41). The storage box (42) is used to store dry sand and is located directly above the sand box (3). The storage box (42) is provided with a discharge port (43) at the lower end. A sand-sprinkling tray (5) is provided inside the discharge port (43). The sand-sprinkling tray (5) is used to guide dry sand to fall evenly into the sand box (3). The dry sand enters the sand box (3) and fills the gap between the sand box (3) and the model cluster to form a mold.

2. The lost foam automated casting device according to claim 1, characterized in that: The sand-drenching tray (5) includes a base plate (51) set inside the discharge port (43), and several evenly distributed discharge holes (511) are opened on the base plate (51). The discharge port (43) is used for dry sand to enter the sand box (3).

3. The lost foam automated casting device according to claim 2, characterized in that: A turntable (52) is rotatably mounted on the chassis (51), and a through hole (521) is opened on the turntable (52) corresponding to the discharge hole (511). An arc-shaped groove (53) is provided on the storage box (42), and a lever (54) connected to the turntable (52) is slidably arranged in the arc-shaped groove (53). The end of the paddle (54) is provided with an arc-shaped rack (541), and the storage box (42) is provided with a drive gear (55) that meshes with the arc-shaped rack (541) via a bracket.

4. The lost foam automated casting device according to claim 1, characterized in that: The sliding bracket (41) is horizontally slidably connected to the support frame (1). A rotating shaft (56) is rotatably provided on the support frame (1). A reciprocating thread section (561) is constructed on the rotating shaft (56) that is threadedly connected to the sliding bracket (41). The storage bin (42) is provided with an extension frame (57) at the lower end, which allows the storage bin (42) to remain connected to the sand box (3) during horizontal displacement.

5. The lost foam automated casting device according to claim 1, characterized in that: The storage box (42) is provided with a casting pipe (6), and the lower end of the casting pipe (6) extends through the storage box (42) to the casting port of the model cluster.

6. The lost foam automated casting device according to claim 5, characterized in that: The casting pipe (6) has a flue gas passage (61) inside, and an outlet (62) connected to the flue gas passage (61) is opened on the outside of the casting pipe (6).

7. The lost foam automated casting device according to claim 6, characterized in that: A membrane applicator (7) is provided on the support frame (1). The membrane applicator (7) is used to seal and retain the pouring port at the upper end of the sand box (3). The film applicator (7) includes a support handle (71) symmetrically and slidably arranged on the support frame (1), a guide rod (72) is provided at the end of the support handle (71), and a connecting plate (73) is slidably arranged on the guide rod (72). A sealing ring (74) corresponding to the sand box (3) is provided between the two connecting plates (73), and a return spring (77) is provided between the connecting plate (73) and the support handle (71).

8. The lost foam automated casting device according to claim 7, characterized in that: A heat-resistant membrane (75) is provided inside the sealing ring (74), and a heat-insulating ring (76) is provided inside the heat-resistant membrane (75). The lower end of the heat-insulating ring (76) corresponds to the casting port of the model cluster, and the section of the heat-insulating ring (76) corresponds to the casting pipe (6).

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