A core shooter

Abstract

This invention provides a core shooter, belonging to the field of intelligent casting island technology. The core shooter includes a frame, a mold closing mechanism, a drive mechanism, a sand storage hopper, an air source assembly, and a sand shooting assembly. The sand shooting assembly includes a limiting frame, a temperature control box, a base plate, and a sand receiving cylinder. The sand receiving cylinder has a flow guiding structure inside, and a flow equalization assembly is sealed between the flow guiding structure and the base plate. The flow equalization assembly contains a pulsating assembly and a temperature control pipeline. The sand enters the storage chamber after being diverted by a conical platform. During sand shooting, the sand flow drives the nozzle to rotate and spray out in a spiral shape. The movable plate and the second spring cooperate to automatically adjust the flow gap between the nozzle and the sand discharge hole according to the weight of the sand. The pulsating assembly generates a high-frequency pulsating jet when the nozzle rotates, which destroys the sand grain arching effect. This invention solves the problem of uneven local compaction of the sand core by means of conical platform diversion, external temperature control box, gravity adaptive gap adjustment, rotating sand shooting, and pulsating jet, thereby improving the filling uniformity of the product and the reliability of the equipment.

Description

Technical Field

[0001] This invention relates to the field of intelligent casting island technology, and more specifically, to a core shooter. Background Technology

[0002] The intelligent casting island, as a modular production unit integrating traditional casting processes with intelligent manufacturing technologies, upgrades the entire sand casting process intelligently by integrating technologies such as automated equipment, sensors, the Internet of Things, big data analysis, and digital twins, achieving continuous process optimization. The core shooter is a core component of the casting island, primarily used for manufacturing sand cores and is an indispensable core-making device in the casting process.

[0003] The core shooting machine operates on a highly efficient automated cycle: First, core sand coated with resin binder is filled into the sand storage bin, and the mold closing mechanism tightly seals the precision-machined metal core box; then, compressed air is released instantaneously, injecting the core sand at high speed into the core box cavity and filling it compactly; next, depending on the process (hot core boxes are cured by heating, and cold core boxes are blown with catalyst gas), the core sand quickly hardens and solidifies within the cavity; finally, the core box opens, and the ejection mechanism smoothly ejects the solidified sand core, completing one core-making cycle.

[0004] Existing core shooting machines suffer from issues such as insufficient or excessive compaction of sand cores during the sand blasting process. For example, during sandblasting, sand particles tend to stack in a cone-shaped pattern, and the varying pressures from different nozzles can easily lead to uneven sand core spraying. Furthermore, traditional sand blasting boxes are large, resulting in significant ineffective expansion of high-pressure gas within the chamber and substantial loss of blasting kinetic energy. The flowability of the sand is also significantly affected by ambient temperature fluctuations, and the blasting holes are prone to clogging due to the solidification of residual sand particles at high temperatures, impacting continuous production.

[0005] How to invent a core-shooting machine to solve these problems has become an urgent issue for those skilled in the art. Summary of the Invention

[0006] To overcome the above deficiencies, the present invention provides a core shooting machine, which aims to solve the problems mentioned in the background.

[0007] This invention is implemented as follows:

[0008] This invention provides a core shooting machine, comprising:

[0009] A frame, on which a mold closing mechanism, a drive mechanism, a sand storage hopper, and an air source assembly for providing a high-pressure air source are provided; the mold closing mechanism is provided with a core box.

[0010] A sand-shooting assembly is mounted on a frame and can selectively communicate with a sand storage hopper and a core box. The sand-shooting assembly includes a limiting frame, a temperature control box, a base plate, and a sand receiving cylinder for storing sand particles. The sand receiving cylinder is fixedly connected to the temperature control box. The base plate is fixedly connected to the bottom of the temperature control box, and the base plate has sand discharge holes that match the channels on the core box. The sand receiving cylinder is elastically connected to the limiting frame via a spring rod structure.

[0011] The sand receiving cylinder is equipped with a flow guiding structure inside, and the lower end of the flow guiding structure extends into the temperature control box; a flow equalization component is fixedly and sealed between the flow guiding structure and the bottom plate, and the flow equalization component is located inside the temperature control box, with its bottom communicating with the sand discharge hole.

[0012] It also includes temperature control piping and a oscillation component, which is located inside the flow equalization component.

[0013] Preferably, the sidewalls of the temperature control box are respectively connected to an input pipe and an output pipe, which are used to communicate with an external temperature control pipeline.

[0014] Preferably, the flow guiding structure includes a guide cylinder disposed inside the sand receiving cylinder and a connecting cylinder fixedly connected to the lower end of the guide cylinder, the connecting cylinder extending into the temperature control box;

[0015] The flow equalization component includes a sand-shooting box and a conical platform fixedly disposed within the connecting cylinder. The sand-shooting box has a storage chamber inside, and a movable plate is slidably connected within the storage chamber. The bottom of the sand-shooting box has several limiting holes corresponding to the sand discharge holes. The conical platform is coaxially arranged with the guide cylinder. The bottom of the connecting cylinder has a slot communicating with the inner cavity of the storage chamber, and the slot is distributed on both sides of the conical platform. Several nozzle assemblies are connected through the bottom of the movable plate, and each nozzle assembly is slidably inserted into the inner side of the corresponding limiting hole. The sand-shooting box also has a first mounting groove inside, and a second spring is fixedly connected within the first mounting groove. The top end of the second spring abuts against and is fixed to the lower side wall of the movable plate.

[0016] Preferably, the nozzle assembly is rotatably connected to the movable plate, and the nozzle assembly is provided with a turbine blade inside. A plurality of sand-shooting holes are opened on the side wall of the nozzle assembly corresponding to the bottom end of the turbine blade. The configuration is such that when the core sand passes through the turbine blade and is ejected from the sand-shooting hole, it can drive the nozzle assembly to rotate around the axis of the limiting hole.

[0017] When sand is fired, the core sand pressure can overcome the elastic force of the second spring to drive the movable plate to move downward, thereby changing the flow gap between the nozzle assembly and the sand discharge hole.

[0018] Preferably, the nozzle assembly includes a main cylinder and a mounting sleeve. The top of the main cylinder is coaxially connected to an elastic corrugated portion, and a limit ring is fixed to the top of the elastic corrugated portion. The limit ring is rotatably mounted on the movable plate. A connecting ring is fixedly connected to the side wall of the main cylinder. The mounting sleeve is fixed to the bottom wall of the movable plate and covers the outside of the connecting ring downwards. The connecting ring and the inner cavity of the mounting sleeve form a sliding guide fit. A first spring is pressed between the top surface of the connecting ring and the bottom wall of the movable plate.

[0019] Preferably, the wave component includes a limiting ring groove opened in the sand-shooting box and a connecting rod fixedly connected to the bottom of the connecting ring. A corrugated guide seat is fixedly installed inside the limiting ring groove. A ball is rotatably engaged at the lower end of the connecting rod. The positions of the connecting rod and the corrugated guide seat correspond to each other in the vertical projection. After the movable plate is pressed down, the connecting rod extends into the corresponding limiting ring groove, and the ball at the end of the connecting rod keeps rolling contact with the upper end surface of the corrugated guide seat.

[0020] Preferably, the cross-section of the sand discharge hole is arranged in a gradually expanding trumpet shape from top to bottom; after the movable plate is pressed, the lower end of the nozzle assembly extends into the sand discharge hole.

[0021] Preferably, the output end of the drive mechanism is provided with an air jet channel, and a pressure plate is fixedly connected to the bottom of the output end of the drive mechanism; the output end of the air source assembly is connected to an air supply pipeline and communicates with the air jet channel through the air supply pipeline; the top of the sand receiving cylinder is provided with a sand receiving port, and the geometric contour of the pressure plate is configured to seal with the sand receiving port.

[0022] Preferably, a second mounting groove is provided on the inner side of the limiting hole, and an annular brush is installed inside the second mounting groove. When the second spring is in the initial state, the position of the sand-shooting hole corresponds to the position of the annular brush. The configuration is such that when sand-shooting ends and the movable plate is reset under the action of the second spring, the annular brush can remove the sand particles remaining at the sand-shooting hole.

[0023] Preferably, the frame is provided with a linear slide rail, the limiting frame is equipped with a guide wheel, and the limiting frame moves back and forth along the linear slide rail by means of the guide wheel; the bottom discharge port of the sand storage hopper is provided with a discharge valve.

[0024] The beneficial effects of this invention are:

[0025] 1. By setting a conical platform and a double-sided slot structure, the sand is forced to flow evenly to the surrounding area before entering the storage chamber, forming a ring distribution, which breaks the traditional conical accumulation pattern of "high in the center and low around the edges" from the source; the movable plate and the second spring cooperate to automatically adjust the annular flow gap between the nozzle assembly and the trumpet-shaped sand discharge hole in real time according to the weight of the sand in the storage chamber; the gap is larger in the early stage of sand shooting (sufficient sand) to ensure that the sand flows through quickly and fills the cavity rapidly; the gap automatically decreases in the later stage of sand shooting (reduced sand) to maintain the jet speed and enhance the throttling effect, avoid the "air penetration" phenomenon, ensure that the residual sand is effectively squeezed out, and significantly improve the uniformity of sand core density.

[0026] 2. The nozzle assembly is equipped with turbine blades, which use the kinetic energy of sand flow to drive the nozzle to rotate at high speed. The sand particles are ejected from the sand injection holes on the side wall in a spiral shape and are evenly distributed to all corners of the core box under the action of centrifugal force, which effectively avoids the problem of sand flow concentration and uneven distribution caused by traditional direct-injection nozzles. The corrugated guide seat in the wave assembly cooperates with the ball bearing to generate high-frequency micro-vibration on the Z-axis when the nozzle rotates, so that the sand flow forms a pulsating jet, which effectively destroys the "arch bridge effect" between sand particles and significantly improves the filling effect of complex cavities (deep holes, narrow grooves, corner dead angles, etc.).

[0027] 3. The temperature control box surrounds the sand-shooting box and controls the temperature fluctuation of the inner wall of the sand-shooting box within ±2℃ through a circulating constant temperature medium (water or heat transfer oil). This prevents the coated sand from solidifying and clumping prematurely, while preheating the sand to reduce viscous resistance. This allows the same equipment to be compatible with various materials such as coated sand and inorganic sand. The storage chamber volume is optimized to 1.0-1.3 times the amount of sand shot per burst, significantly reducing the ineffective expansion of high-pressure gas. The sand-shooting kinetic energy is highly concentrated, resulting in better sand-shooting effect under the same air pressure and lower energy consumption.

[0028] 4. An annular brush is installed inside the limiting hole. After sand shooting, the movable plate is reset under the action of the spring. The sand shooting hole wipes upwards past the annular brush, automatically removing the sand particles that may have solidified prematurely due to high temperature. No additional power is required, which greatly reduces the failure rate in high temperature and harsh environments and increases the continuous maintenance-free operation cycle. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0031] Figure 2This is a schematic diagram of the right-side cross-sectional structure of the present invention;

[0032] Figure 3 This is a schematic diagram of the distribution structure of the drive mechanism and air source components of the present invention;

[0033] Figure 4 This is a schematic diagram of the sand-shooting assembly and drive mechanism of the present invention;

[0034] Figure 5 This is a cross-sectional structural diagram of the sand-shooting assembly and drive mechanism of the present invention;

[0035] Figure 6 This is a schematic diagram of the sand-shooting assembly structure of the present invention;

[0036] Figure 7 This is a cross-sectional structural diagram of the sand-shooting assembly of the present invention in its initial state;

[0037] Figure 8 This is the invention Figure 7 Enlarged structural diagram at point A in the middle;

[0038] Figure 9 This is a cross-sectional structural diagram of the sand-shooting assembly of the present invention in its working state;

[0039] Figure 10 This is the invention Figure 9 Enlarged structural diagram at point B;

[0040] Figure 11 This is a schematic diagram of the cross-sectional structure of the sand-shooting box and the base plate of the present invention;

[0041] Figure 12 This is a schematic diagram of the corrugated guide seat structure of the present invention;

[0042] Figure 13 This is a schematic diagram of the nozzle assembly structure of the present invention;

[0043] Figure 14 This is a schematic cross-sectional view of the nozzle assembly of the present invention.

[0044] In the diagram: 1. Frame; 2. Mold clamping mechanism; 3. Sand injection assembly; 4. Drive mechanism; 5. Sand storage hopper; 6. Air source assembly; 7. Sand injection box; 8. Nozzle assembly; 9. Limiting ring groove; 21. Core box; 31. Limiting frame; 32. Sand receiving cylinder; 33. Temperature control box; 34. Base plate; 41. Air jet channel; 42. Pressure plate; 51. Unloading valve; 71. Material storage chamber; 72. Movable plate; 73. Mounting sleeve; 74. Connecting ring; 75. First mounting groove; 76. Second... Mounting slot; 80, limiting hole; 81, main cylinder; 82, turbine blade; 83, sand-shooting hole; 91, connecting rod; 92, corrugated guide seat; 311, guide wheel; 320, sand inlet; 321, guide cylinder; 322, connecting cylinder; 323, conical platform; 331, input pipe; 332, output pipe; 341, sand discharge hole; 741, first spring; 751, second spring; 761, annular brush; 811, elastic corrugated part; 812, limiting retaining ring. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] Example 1, refer to Figures 1-14 A core shooting machine, comprising:

[0047] The frame 1 is equipped with a mold clamping mechanism 2, a drive mechanism 4, a sand storage hopper 5, and an air source assembly 6 for providing a high-pressure air source. The mold clamping mechanism 2 is equipped with a core box 21. The mold clamping mechanism 2 is used to fix the core box 21 and provide mold clamping force. The drive mechanism 4 is used to realize the lifting or moving of the sand shooting assembly 3. The sand storage hopper 5 is used to store core sand. The air source assembly 6 provides high-pressure gas as sand shooting power.

[0048] The sand-shooting assembly 3 is installed on the frame 1 and can selectively communicate with the sand storage hopper 5 and the core box 21. When receiving sand, it connects with the sand storage hopper 5, and when shooting sand, it connects with the core box 21 to prevent sand leakage. The sand-shooting assembly 3 includes a limiting frame 31, a temperature control box 33, a base plate 34, and a sand receiving cylinder 32 for storing sand particles. The sand receiving cylinder 32 is fixedly connected to the temperature control box 33. The base plate 34 is fixedly connected to the bottom of the temperature control box 33, and the base plate 34 has a sand discharge hole 341 that matches the channel on the core box 21. The sand receiving cylinder 32 is elastically connected to the limiting frame 31 through a spring rod structure to ensure that the sand receiving cylinder 32 can automatically reset when the drive mechanism 4 resets.

[0049] The sand receiving cylinder 32 is equipped with a flow guiding structure inside, and the lower end of the flow guiding structure extends into the temperature control box 33. It can guide the sand from the sand storage hopper 5 from the central sand inlet to the flow equalization component, so as to avoid the sand from accumulating randomly or forming a cone-shaped accumulation in the sand receiving cylinder 32. The flow equalization component is fixedly and sealed between the flow guiding structure and the bottom plate 34. The flow equalization component is located inside the temperature control box 33, and its bottom is connected to the sand discharge hole 341. The flow equalization component is responsible for evenly distributing the sand to each sand discharge hole 341 to ensure that the sand output of the multiple holes is consistent.

[0050] It also includes a temperature control pipeline and a ripple component. The temperature control pipeline (not shown in the figure) enables precise temperature regulation. The ripple component is set inside the flow equalization component. The ripple component causes the sand flow to generate tiny ripples during the spraying process, which disrupts the stable accumulation pattern of sand particles and improves the uniformity of filling.

[0051] Furthermore, the side wall of the temperature control box 33 is connected to an input pipe 331 and an output pipe 332, respectively. The input pipe 331 and the output pipe 332 are used to connect with an external temperature control pipeline. The external temperature control pipeline can be connected to a constant temperature water tank, an oil temperature controller or a mold temperature controller to provide a stable circulating medium (water, heat transfer oil or antifreeze).

[0052] Furthermore, the output end of the drive mechanism 4 is provided with an air jet channel 41, and the bottom of the output end of the drive mechanism 4 is fixedly connected to a pressure plate 42; the output end of the air source component 6 is connected to an air supply pipeline and communicates with the air jet channel 41 through the air supply pipeline; the top of the sand receiving cylinder 32 is provided with a sand receiving port 320, and the geometric contour of the pressure plate 42 is sealed to the sand receiving port 320.

[0053] Furthermore, a linear slide rail is laid on the frame 1, and a guide wheel 311 is mounted on the limiting frame 31. The limiting frame 31 moves back and forth along the linear slide rail by relying on the guide wheel 311; a discharge valve 51 is provided at the bottom discharge port of the sand storage hopper 5.

[0054] It should be noted that the size of the sand-shooting box 7 and the sand-receiving cylinder 32 of the present invention is not fixed, but is selected according to actual production needs. The volume of the sand-receiving cylinder 32 should be at least 1.2 times greater than the maximum sand-shooting volume in a single shot to ensure sufficient residual sand reserve and avoid dry shooting during the sand-shooting process. When selecting the specific model, it can be calculated based on the weight of the sand core, the cavity volume of the core box 21, and the bulk density of the coated sand. The volume of the sand-shooting box 7 of traditional core shooters is often too large (usually 3-5 times the sand-shooting volume in a single shot), which causes the high-pressure gas to expand significantly in the cavity and cause serious pressure loss. The present invention adopts the concept of "small box sand shooting", and the volume of the storage cavity 71 is controlled between 1.0 and 1.3 times the sand-shooting volume in a single shot.

[0055] In this embodiment, during the sand receiving stage: the external cylinder controls the sand shooting assembly to move along the linear slide rail, and the sand receiving cylinder 32 pushes the unloading valve 51 (a slide valve can be selected) to open, so that the core sand in the sand storage hopper 5 falls into the sand receiving cylinder 32. The sand receiving cylinder 32 is elastically supported on the limiting frame 31 by the spring rod structure, and can sink slightly as the amount of sand increases to avoid impact. The volume of the sand receiving cylinder 32 is pre-selected according to the maximum single sand shooting amount to ensure that there is enough residual sand reserve.

[0056] Moving docking stage: After the sand receiving is completed, the external cylinder pushes the sand shooting component 3 to move along the linear slide rail to directly above the core box 21. At this time, the output end of the drive mechanism 4 (which can be a hydraulic cylinder) presses down, the pressure plate 42 seals the sand receiving port 320, and aligns the sand discharge hole 341 of the bottom plate 34 with the sand inlet hole of the core box 21 to form a closed sand shooting chamber.

[0057] Sand-shooting stage: The air source component 6 provides high-pressure gas, which enters the top of the sand receiving cylinder 32 through the jet channel 41, presses the sand material downward through the guide structure into the flow equalization component, and the flow equalization component evenly distributes the sand material to each sand discharge hole 341. The oscillation component introduces periodic pressure fluctuations in the sand flow, so that the sand particles fill the cavity of the core box 21 more evenly. Since the volume of the storage cavity 71 of the sand-shooting box 7 is optimized to be only slightly larger than the single sand-shooting volume (preferably 1.1-1.2 times), the ineffective expansion of the high-pressure gas in the cavity is significantly suppressed, and the sand-shooting kinetic energy is highly concentrated. At the same time, the temperature control pipeline circulates the constant temperature medium through the input pipe 331 and the output pipe 332, so that the temperature of the inner wall of the sand-shooting box 7 is stabilized within the preset process range (usually 35℃-45℃), and the sand material reaches the optimal fluidity state before being shot.

[0058] Venting and curing: The venting grooves / venting plugs on the core box 21 promptly vent the gas in the cavity. The hot core box heats the mold to the set temperature (usually 200℃-260℃) through the electric heating element, causing the thermosetting resin in the coated sand to cross-link and cure, forming a high-strength sand core.

[0059] Reset: After sand shooting is completed, the drive mechanism 4 retracts, the sand receiving cylinder 32 resets under the action of the spring rod, and the pressure plate 42 disengages from the sand receiving port 320, waiting for the next cycle.

[0060] The temperature control box 33 has a box-like structure and covers the periphery of the sand shooting box 7, forming a circulation cavity between the two. The side walls of the temperature control box 33 are connected to the input pipe 331 and the output pipe 332, respectively, for communication with the external temperature control pipeline. The external temperature control pipeline can be connected to a constant temperature water tank, oil temperature controller or mold temperature controller to provide a stable circulation medium (water, heat transfer oil or antifreeze). The temperature control box 33 can adjust the sand temperature, improve the fluidity of the coated sand or prevent premature curing.

[0061] Traditional core shooters indirectly affect the sand temperature only through mold heating, resulting in significant temperature control lag and poor uniformity. This invention directly controls the temperature of the sand shooting box 7, allowing the temperature fluctuation of the inner wall of the sand shooting box 7 to be controlled within ±2℃. When the temperature of coated sand exceeds 60℃, resin pre-crosslinking may occur, leading to sand particle agglomeration and blockage of the sand shooting holes 83. The temperature control component locks the temperature of the sand shooting box 7 within a safe range, avoiding such problems. In addition, proper preheating (35℃-45℃) can reduce the viscous resistance of the coated sand, making the sand particles easier to be carried by airflow and fill deeper and narrower cavity dead corners. By adjusting the medium temperature, the same equipment can be compatible with various materials such as coated sand and inorganic sand, improving the equipment's versatility.

[0062] The sand-shooting box 7 designed in this invention shortens the residence time of sand particles in the cavity, minimizes compressed air energy loss, reduces air source energy consumption, concentrates sand-shooting kinetic energy, and achieves better sand-shooting effect under the same air pressure. The compact sand-shooting box 7 cavity, combined with the flow equalization component, fundamentally eliminates the common problems of conical accumulation and uneven sand-shooting pressure in traditional large-volume sand-shooting boxes 7. The sand-shooting box 7 is surrounded by a temperature control box 33, which controls the temperature fluctuation of the inner wall of the sand-shooting box 7 within ±2℃ through a circulating constant temperature medium, significantly improving the consistency of core sand flowability. The temperature control component locks the temperature of the sand-shooting box 7 within a safe range (35℃-45℃), preventing resin pre-crosslinking of coated sand in the sand-shooting box 7 and reducing the risk of blockage. Through the synergy of the flow guiding structure, the flow equalization component, and the flow fluctuation component, the problems of uneven sand accumulation and jet pulsation are eliminated from the source, further improving the uniformity of sand core density.

[0063] Example 2, refer to Figures 5-8 The flow guiding structure includes a guide cylinder 321 disposed inside the sand receiving cylinder 32 and a connecting cylinder 322 fixedly connected to the lower end of the guide cylinder 321. The connecting cylinder 322 extends into the temperature control box 33. The guide cylinder 321 guides the sand to fall vertically, and the connecting cylinder 322 further concentrates the sand and introduces it into the flow equalization component. The two together form a smooth sand flow channel, reducing turbulence.

[0064] Furthermore, the flow equalization component includes a sand-shooting box 7 and a conical platform 323 fixedly installed inside the connecting cylinder 322. The sand-shooting box 7 has a storage chamber 71 inside, and a movable plate 72 is slidably connected inside the storage chamber 71. The bottom of the sand-shooting box 7 has several limiting holes 80 corresponding to the sand discharge hole 341. The conical platform 323 is coaxially arranged with the guide cylinder 321. The bottom of the connecting cylinder 322 has a slot that connects to the inner cavity of the storage chamber 71. The slots are distributed on both sides of the conical platform 323. The conical platform 323 forces the sand flow falling from the center to be diverted to the surrounding areas, breaking the naturally formed conical accumulation pattern of "high in the center and low around the edges" of the sand particles, so that the sand entering the storage chamber 71 is evenly distributed in a ring. The sand diverted by the conical platform 323 enters the storage chamber 71 symmetrically from the slots on both sides, ensuring a balance of sand supply from left to right.

[0065] Furthermore, a number of nozzle assemblies 8 are connected through the bottom of the movable plate 72, and each nozzle assembly 8 is slidably inserted into the inner side of the corresponding limiting hole 80. The sand-shooting box 7 is also provided with a first mounting groove 75, and a second spring 751 is fixedly connected in the first mounting groove 75. The top of the second spring 751 abuts against and is fixed to the lower side wall of the movable plate 72. The movable plate 72 can float up and down under the action of sand pressure and spring force, dynamically adjusting the sand-shooting volume of each nozzle assembly 8 to achieve adaptive flow balance. The second spring 751 provides initial preload force so that the movable plate 72 is kept in a high position when there is no sand pressure. When shooting sand, the sand pressure overcomes the spring force and pushes the movable plate 72 down, thereby changing the flow gap between the nozzle assembly 8 and the sand discharge hole 341, realizing positive feedback adjustment that the greater the sand pressure, the greater the opening.

[0066] Furthermore, the nozzle assembly 8 is rotatably connected to the movable plate 72. The nozzle assembly 8 is provided with a turbine blade 82 inside. A number of sand-shooting holes 83 are opened on the side wall of the nozzle assembly 8 corresponding to the bottom of the turbine blade 82. The configuration is such that when the core sand passes through the turbine blade 82 and is sprayed out from the sand-shooting holes 83, it can drive the nozzle assembly 8 to rotate around the axis of the limiting hole 80.

[0067] It should be noted that the cross-section of the sand discharge hole 341 is arranged in a gradually expanding trumpet shape from top to bottom; after the movable plate 72 is pressed, the lower part of the nozzle assembly 8 extends into the sand discharge hole 341; when sand is shot, the core sand pressure can overcome the elastic force of the second spring 751 to drive the movable plate 72 to move downward, so as to change the flow gap between the nozzle assembly 8 and the sand discharge hole 341. When the nozzle assembly 8 moves downward and extends into the trumpet-shaped sand discharge hole 341, the flow gap gradually increases.

[0068] In this embodiment, the sand material falls vertically from the receiving cylinder 32 through the guide cylinder 321, impacts the top of the conical platform 323, and then disperses evenly around the cone surface. It then enters the storage chamber 71 symmetrically from the slots on both sides of the bottom of the connecting cylinder 322. At this time, the sand material has formed a ring-shaped and uniform distribution in the storage chamber 71, rather than being piled up in the center.

[0069] Initial state (full of sand): The storage chamber 71 is filled with sand. The weight of the sand compresses the second spring 751 through the movable plate 72. The movable plate 72 is in a lower position. At this time, the lower end of the nozzle assembly 8 extends deeper into the sand discharge hole 341. Since the sand discharge hole 341 is funnel-shaped (smaller at the top and larger at the bottom), the diameter of the hole at the deeper position is larger. Therefore, the annular flow gap between the outer wall of the nozzle and the inner wall of the sand discharge hole 341 is larger.

[0070] During sand injection (sand quantity decreases): As the amount of sand gradually decreases, the total weight of the sand decreases, the downward pressure on the movable plate 72 decreases, and under the elastic force of the second spring 751, the movable plate 72 gradually rises, and the lower end of the nozzle assembly 8 gradually exits and rises from the sand discharge hole 341. Since the flared mouth is smaller at the top and larger at the bottom, when the nozzle retracts to a shallower position, the corresponding hole diameter is smaller, so the annular flow gap gradually decreases.

[0071] When the storage chamber 71 is full of sand, the sand layer is at its thickest. At this time, when the high-pressure air penetrates this thick layer of sand, it encounters the greatest fluid resistance and the greatest energy loss. At the same time, a large number of sand particles are squeezed at the bottom, which can easily cause friction bridging and blockage.

[0072] When the sand is full, the gap of the movable plate 72 is at its maximum due to the pressure of the sand. This greatly reduces the throttling resistance at the sand discharge hole 341, compensates for the energy loss of air penetrating the sand layer, and the large gap ensures that the sand flow can still be smoothly ejected with a huge volume flow rate when the initial sand shooting resistance is at its maximum, completely eliminating the "suffocation" and "blockage" phenomena in the full sand state.

[0073] In the case of less sand, as the amount of sand decreases and the sand layer becomes thinner, the resistance of high-pressure air penetrating the sand layer drops sharply. If the sand discharge hole 341 still maintains a large gap, the high-pressure airflow will directly penetrate the remaining sand along the path of least resistance and be ejected (air penetration). This will cause a large amount of gas to be injected into the mold, while very little sand is carried out, resulting in a loose sand core defect.

[0074] As the amount of sand decreases, the second spring 751 lifts the movable plate 72, and the nozzle retracts to the narrow part of the flared mouth. The gap automatically decreases, increasing the physical resistance at the sand discharge hole 341 (establishing back pressure). On the one hand, it forcibly limits the excessively rapid loss of air and prevents "air penetration". On the other hand, according to Bernoulli's principle, a smaller flow cross section will cause the flow rate to surge. This allows the remaining sand particles to still be given extremely high injection kinetic energy at the end when the amount of sand is small and the overall pressure drops, ensuring that the compactness does not decrease at the end of the sand injection. At the same time, the enhanced throttling effect helps to squeeze out the residual sand.

[0075] When sand particles flow through the turbine blades 82 inside the nozzle assembly 8, the impact kinetic energy of the sand particles is converted into the rotational torque of the turbine blades 82, driving the nozzle assembly 8 to rotate at high speed around the axis of the limiting hole 80. The sand particles are ejected in a spiral shape from the sand injection holes 83 opened on the side wall of the nozzle assembly 8. Under the action of centrifugal force, they are evenly distributed to all corners of the cavity of the core box 21, effectively avoiding the problem of concentrated and uneven sand flow caused by traditional direct-shot nozzles. After the sand injection is completed, the air source assembly 6 stops supplying air, and the sand pressure disappears. At this time, the elastic force of the second spring 751 is greater than the residual pressure borne by the movable plate 72, pushing the movable plate 72 to move upward and reset.

[0076] The conical platform 323 and the double-sided slot structure force the sand to be evenly distributed before entering the storage chamber 71; the movable plate 72 cooperates with the second spring 751 to automatically adjust the sand injection gap according to the real-time sand pressure. The large gap at the beginning of sand injection ensures smooth sand flow and quickly covers the main area of ​​the cavity; the small gap in the later stage of sand injection maintains the injection speed to ensure that the residual sand can also effectively fill the dead corners and reduce the loose sand core defects; during sand injection, the nozzle assembly 8 rotates automatically, so that the sand flow is scattered in a conical shape, with a large coverage area and strong ability to fill dead corners.

[0077] Example 3, referring to Figures 6-14 The nozzle assembly 8 includes a main cylinder 81 and a mounting sleeve 73. An elastic corrugated section 811 (made of wear-resistant metal bellows, capable of transmitting torque and absorbing microscopic high-frequency vibration deformation in the Z-axis direction, ensuring absolute sealing of the sand flow channel) is coaxially connected to the top of the main cylinder 81. A limit ring 812 is fixed to the top of the elastic corrugated section 811. The limit ring 812 is rotatably mounted on the movable plate 72, enabling rotational freedom of the entire nozzle assembly 8 while restricting axial detachment. The elastic corrugated section 811 allows the main cylinder 81 to have a certain degree of rotation relative to the movable plate 72. The main cylinder 81 has a fixed axial extension and contraction; a connecting ring 74 is fixedly connected to the side wall of the main cylinder 81, and the mounting sleeve 73 is fixed to the bottom wall of the movable plate 72 and covers the outside of the connecting ring 74 downward. The connecting ring 74 and the inner cavity of the mounting sleeve 73 form a sliding guide fit, so that the main cylinder 81 can slide up and down relative to the movable plate 72, while restricting radial swing. A first spring 741 is pressed between the top surface of the connecting ring 74 and the bottom wall of the movable plate 72 to provide auxiliary elastic force. Together with the second spring 751, it adjusts the extension length of the nozzle assembly 8 and the sand shooting pressure response characteristics.

[0078] Furthermore, the wave component includes a limiting ring groove 9 opened in the sand-shooting box 7 and a connecting rod 91 fixedly connected to the bottom of the connecting ring 74. A corrugated guide seat 92 is fixedly installed inside the limiting ring groove 9, and a ball is rotatably engaged at the lower end of the connecting rod 91 to reduce friction.

[0079] It should be noted that the positions of the connecting rod 91 and the corrugated guide seat 92 correspond in the vertical projection; after the movable plate 72 is pressed down, the connecting rod 91 extends into the corresponding limiting ring groove 9, and the ball at the end of the connecting rod 91 keeps rolling contact with the upper end surface of the corrugated guide seat 92, and the upper end surface of the corrugated guide seat 92 has a corrugated profile with high and low undulations; when the connecting rod 91 moves down with the movable plate 72 and extends into the limiting ring groove 9, the ball rolls along the corrugated surface, forcing the connecting rod 91 to drive the main cylinder 81 to produce periodic small axial vibrations.

[0080] In this embodiment, the corrugated guide seat 92 is fixed in the limiting ring groove 9. Only when the movable plate 72 in embodiment 2 moves down due to pressure (macro displacement) will the ball at the bottom of the connecting rod 91 outside the nozzle assembly 8 come into contact with the corrugated guide seat 92. When the movable plate 72 does not move down or moves down too little, the ball does not come into contact with the corrugated guide seat 92, the corrugated assembly does not work, and unnecessary wear is reduced.

[0081] Under the fluid spin drive of Embodiment 2, the main cylinder 81 of the nozzle assembly 8 drives the connecting rod 91 to rotate synchronously. The balls roll and undulate on the corrugated surface, forcing the main cylinder 81 to generate high-frequency micro-vibration along the Z-axis. This vibration is transmitted to the sand flow, forming a high-frequency pulsating jet, which effectively destroys the "arch bridge effect" between sand particles, allowing the sand flow to enter the core box 21 in a looser and more uniform state, significantly improving the filling effect of complex cavities (such as deep holes, narrow grooves, corner dead angles, etc.). When the main cylinder 81 vibrates at high frequency, the mounting sleeve 73 and the connecting ring 74 slide relative to each other. The first spring 741 absorbs the vibration energy and keeps the balls pressed. The elastic corrugated part 811 then generates high-frequency expansion and contraction deformation, absorbing micro-vibration displacement.

[0082] This embodiment constructs a nested double floating mechanism, which not only utilizes macroscopic displacement to achieve on-demand triggering of the excitation function (no vibration when the pressure is low, reducing wear), but also, through the elastic corrugated part 811, endows the sand jet with high-frequency pulse characteristics while ensuring absolute sealing. This effectively destroys the frictional bridging effect between sand particles in dead corners, solves the technical pain point of incomplete filling in dead corners, and significantly improves the overall yield of sand cores.

[0083] In embodiment four, a second mounting groove 76 is provided on the inner side of the limiting hole 80, and an annular brush 761 is installed inside the second mounting groove 76. When the second spring 751 is in the initial state, the position of the sand-shooting hole 83 corresponds to the position of the annular brush 761. The configuration is such that when sand-shooting ends and the movable plate 72 is reset under the action of the second spring 751, the annular brush 761 can remove the sand particles remaining at the sand-shooting hole 83.

[0084] The temperature of the hot core box 21 is extremely high during operation (although the temperature control box 33 alleviates the problem, radiant heat still exists). After the sand injection is completed, the residual resin sand remaining inside the nozzle assembly 8 is easily heated and will solidify prematurely, clogging the sand injection hole 83 and causing the next mold closing sand injection to fail.

[0085] In this embodiment, when the sand-shooting action is performed, the movable plate 72 is in a state of being pressed down, and the sand-shooting hole 83 extends downward to avoid the annular brush 761 for normal sand distribution. When a single sand-shooting action ends, the air source is cut off, the pressure in the storage chamber 71 drops sharply, and the movable plate 72 instantly returns to its original position under the elastic restoring force of the second spring 751. At this instant of resetting, the sand-shooting hole 83 on the side wall of the nozzle assembly 8 just forcibly rubs past the annular brush 761 fixed in the second mounting groove 76. The bristles pierce into the hole and instantly scrape away the residual resin sand that is accumulating on the edge and inside the hole.

[0086] Without the need for any additional cylinders, motors, or other drive equipment, precise timing anti-clogging cleaning is achieved solely through the reset stroke in one sand-shooting cycle. This significantly reduces the failure rate of the equipment in high-temperature and harsh environments and extends the continuous maintenance-free operation cycle of the core shooter.

[0087] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the invention by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A core shooting machine, characterized in that, include: A frame (1) is provided with a mold closing mechanism (2), a drive mechanism (4), a sand storage hopper (5), and an air source assembly (6) for providing a high-pressure air source. The mold closing mechanism (2) is provided with a core box (21). A sand-shooting assembly (3) is installed on the frame (1) and can selectively communicate with the sand storage hopper (5) and the core box (21); the sand-shooting assembly (3) includes a limiting frame (31), a temperature control box (33), a base plate (34), and a sand receiving cylinder (32) for storing sand particles. The sand receiving cylinder (32) is fixedly connected to the temperature control box (33); the base plate (34) is fixedly connected to the bottom of the temperature control box (33), and the base plate (34) has a sand discharge hole (341) that matches the channel on the core box (21); the sand receiving cylinder (32) is elastically connected to the limiting frame (31) through a spring rod structure. The sand receiving cylinder (32) is provided with a flow guiding structure inside, and the lower end of the flow guiding structure extends into the temperature control box (33); a flow equalization component is fixedly and sealed between the flow guiding structure and the bottom plate (34), and the flow equalization component is located inside the temperature control box (33), and its bottom is connected to the sand discharge hole (341). It also includes temperature control piping and a oscillation component, which is located inside the flow equalization component.

2. A core shooter according to claim 1, characterized in that, The side wall of the temperature control box (33) is connected to an input pipe (331) and an output pipe (332), which are used to connect with an external temperature control pipeline.

3. A core shooter according to claim 1, characterized in that, The flow guiding structure includes a guide cylinder (321) disposed inside the sand receiving cylinder (32) and a connecting cylinder (322) fixedly connected to the lower end of the guide cylinder (321), the connecting cylinder (322) extending into the temperature control box (33); The flow equalization assembly includes a sand-shooting box (7) and a conical platform (323) fixedly disposed within the connecting cylinder (322). The sand-shooting box (7) has a storage chamber (71) inside, and a movable plate (72) is slidably connected within the storage chamber (71). The bottom of the sand-shooting box (7) has several limiting holes (80) corresponding to the sand discharge hole (341). The conical platform (323) is coaxially arranged with the guide cylinder (321), and the bottom of the connecting cylinder (322) is provided with a connection to the storage chamber (71). 1) The groove of the inner cavity is distributed on both sides of the conical platform (323); a number of nozzle assemblies (8) are connected through the bottom of the movable plate (72), and each nozzle assembly (8) is slidably inserted into the inner side of the corresponding limiting hole (80); the inside of the sand shooting box (7) is also provided with a first mounting groove (75), and a second spring (751) is fixedly connected in the first mounting groove (75), and the top end of the second spring (751) abuts against and is fixed to the lower side wall of the movable plate (72).

4. A core shooting machine according to claim 3, characterized in that, The nozzle assembly (8) is rotatably connected to the movable plate (72). The nozzle assembly (8) is provided with a turbine fan blade (82) inside. A plurality of sand-shooting holes (83) are opened on the side wall of the nozzle assembly (8) corresponding to the bottom end of the turbine fan blade (82). It is configured such that when the core sand passes through the turbine fan blade (82) and is sprayed out from the sand-shooting hole (83), it can drive the nozzle assembly (8) to rotate around the axis of the limiting hole (80). When sand is shot, the core sand pressure can overcome the elastic force of the second spring (751) to drive the movable plate (72) to move down, thereby changing the flow gap between the nozzle assembly (8) and the sand discharge hole (341).

5. A core shooter according to claim 4, characterized in that, The nozzle assembly (8) includes a main cylinder (81) and a mounting sleeve (73). The top of the main cylinder (81) is coaxially connected to an elastic corrugated part (811). A limiting ring (812) is fixed to the top of the elastic corrugated part (811). The limiting ring (812) is rotatably mounted on the movable plate (72). A connecting ring (74) is fixedly connected to the side wall of the main cylinder (81). The mounting sleeve (73) is fixed to the bottom wall of the movable plate (72) and covers the outside of the connecting ring (74). The connecting ring (74) and the inner cavity of the mounting sleeve (73) form a sliding guide fit. A first spring (741) is pressed between the top surface of the connecting ring (74) and the bottom wall of the movable plate (72).

6. A core shooter according to claim 5, characterized in that, The wave component includes a limiting ring groove (9) opened in the sand-shooting box (7) and a connecting rod (91) fixedly connected to the bottom of the connecting ring (74). A corrugated guide seat (92) is fixedly installed inside the limiting ring groove (9). A ball is rotatably engaged at the lower end of the connecting rod (91). The positions of the connecting rod (91) and the corrugated guide seat (92) correspond to each other in the vertical projection. After the movable plate (72) is pressed down, the connecting rod (91) extends into the corresponding limiting ring groove (9), and the ball at the end of the connecting rod (91) keeps rolling contact with the upper end face of the corrugated guide seat (92).

7. A core shooter according to claim 4, characterized in that, The cross-section of the sand discharge hole (341) is arranged in a gradually expanding trumpet shape from top to bottom; after the movable plate (72) is pressed, the lower part of the nozzle assembly (8) extends into the sand discharge hole (341).

8. A core shooting machine according to claim 1, characterized in that, The output end of the drive mechanism (4) is provided with an air jet channel (41), and the bottom of the output end of the drive mechanism (4) is fixedly connected to a pressure plate (42); the output end of the air source assembly (6) is connected to an air supply pipeline, and communicates with the air jet channel (41) through the air supply pipeline; the top of the sand receiving cylinder (32) is provided with a sand receiving port (320), and the geometric contour of the pressure plate (42) is sealed to the sand receiving port (320).

9. A core shooting machine according to claim 4, characterized in that, The inner side of the limiting hole (80) is provided with a second mounting groove (76), and an annular brush (761) is installed inside the second mounting groove (76). When the second spring (751) is in the initial state, the position of the sand-shooting hole (83) corresponds to the position of the annular brush (761). The configuration is such that when the sand-shooting ends and the movable plate (72) is reset under the action of the second spring (751), the annular brush (761) can remove the sand particles remaining at the sand-shooting hole (83).

10. A core shooter according to claim 1, characterized in that, The frame (1) is provided with a linear slide rail, and the limiting frame (31) is equipped with a guide wheel (311). The limiting frame (31) moves back and forth along the linear slide rail by relying on the guide wheel (311). The bottom outlet of the sand storage hopper (5) is provided with a discharge valve (51).

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