A coremaking machine and shot, cure process control method

Abstract

The present application relates to the technical field of metal casting, and particularly discloses a core making machine, which is provided with at least two regulating systems in the circumferential direction of the side wall of a core box. During sand shooting, the exhaust adjusting branch of the regulating system controls the exhaust amount during sand shooting to avoid excessive pressure drop loss, and the negative pressure adjusting branch adjusts the vacuum degree in the cavity to increase the pressure difference between the region and other regions, improve the flowability of the sand, and facilitate compacting of the sand, thereby achieving good core making effect. During solidification and blowing, the blowing mechanism can blow triethylamine gas into the cavity through the top and side of the core box, achieve the best solidification and air intake combination, increase the air intake area, shorten the solidification time, improve the solidification efficiency, and increase the opening of the exhaust adjusting branch to increase the exhaust amount of the corresponding region and ensure smooth air intake. The present application also provides a sand shooting and solidification process control method applied to the core making machine.

Description

Technical Field

[0001] This invention relates to the field of metal casting technology, and in particular to a core-making machine and a method for controlling the sand-shooting and solidification processes. Background Technology

[0002] In metal casting processes, sand core casting is commonly used to prepare castings with hollow structures. This requires the preparation of sand cores corresponding to the hollow structure of the casting, and sand core forming is generally achieved using a core-making machine. In the cold core process, after the core box of the core-making machine is closed, there are sand injection and air blowing solidification steps. In existing technologies, for vertical sand injection core making, a top sand injection and top air blowing method is generally used. That is, during sand injection, sand is injected into the core box from the sand inlet at the top of the core box through the sand injection mechanism. After sand injection is completed, the sand injection mechanism is removed, and the air blowing mechanism is moved to the sand inlet to blow triethylamine gas into the core, thereby solidifying the sand core.

[0003] However, when the height of the sand core exceeds 1 meter, the top sand injection method results in a long airflow path, a large core box cavity, and a large pressure drop loss during sand injection. This leads to lower pressure at the far end of the injection port, making it difficult to control the air-sand ratio. Consequently, the sand core cannot be compacted, resulting in poor quality of the hollow structure in subsequent castings. In addition, during the curing process, amine is only introduced through the top sand inlet, resulting in a small amine inlet area. Furthermore, the presence of exhaust ports near the sand inlet area makes it difficult for the curing agent to effectively contact the sand core located at the bottom, leading to poor sand core curing and a long air-blowing curing time.

[0004] Therefore, there is an urgent need for a core-making machine and a method for controlling the sand-shooting and curing processes to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a core-making machine and a method for controlling the sand injection and curing process. During sand injection, the molding sand has high fluidity, the sand cores at each position are tightly filled, the amine injection area is large, the curing time is short, the core-making effect is good, and the core-making efficiency is high.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] On one hand, the present invention provides a chip-making machine, comprising:

[0008] The core box has a hollow interior forming a cavity. The top of the core box is provided with a sand inlet that communicates with the cavity. The sand inlet is selectively connected to a sand-shooting mechanism or an air-blowing mechanism.

[0009] At least two sealing covers are disposed around the side wall of the core box, each sealing cover is provided with an exhaust port, the sealing covers and the side wall of the core box form an exhaust cavity, the exhaust cavity is connected to the cavity and the exhaust port;

[0010] The control system corresponds one-to-one with the sealing cover. Each control system includes an exhaust regulating branch, a negative pressure regulating branch, and a positive pressure regulating branch that are connected to the exhaust port. The exhaust regulating branch is used to regulate the exhaust volume of the cavity, the negative pressure regulating branch is used to regulate the vacuum level in the cavity, and the positive pressure regulating branch is connected to the blowing mechanism and is used to regulate the amine intake of the blowing mechanism.

[0011] Optionally, a first valve assembly is provided on the exhaust regulating branch, and the exhaust volume of the cavity is adjusted by controlling the opening degree of the first valve assembly;

[0012] The negative pressure regulating branch is equipped with a vacuum device and a second valve assembly. One end of the negative pressure regulating branch is connected to the exhaust port. The vacuum device is used to create a vacuum condition, and the second valve assembly is used to regulate the vacuum level in the cavity.

[0013] A third valve assembly is provided on the positive pressure regulating branch, and the amount of amine introduced into the blowing mechanism is adjusted by controlling the opening degree of the third valve assembly.

[0014] Optionally, the first valve assembly includes a first manual valve and a first solenoid valve, wherein the first manual valve is disposed upstream of the first solenoid valve;

[0015] The second valve assembly includes a second manual valve, a second solenoid valve, and a first vacuum valve. The first vacuum valve is located upstream of the second manual valve, the second manual valve is located upstream of the vacuum device, and the second solenoid valve is located downstream of the vacuum device.

[0016] The third valve assembly includes a third manual valve, a third solenoid valve, and a second vacuum valve, wherein the second vacuum valve is located upstream of the third manual valve, and the third manual valve is located upstream of the third solenoid valve.

[0017] Optionally, the exhaust chamber is connected to the mold cavity through air holes provided on the side wall of the core box, and each exhaust chamber is provided with a plurality of air holes.

[0018] Optionally, an exhaust plug is embedded in the side wall of the core box. The exhaust plug is used to block the air hole and is configured to allow gas to pass through.

[0019] Optionally, the blowing mechanism includes a gas generator, a first air supply pipe, and an air blowing plate. The first air supply pipe is connected to the gas generator, and the air blowing plate and the top wall of the core box form an air blowing chamber. The air blowing chamber is connected to the first air supply pipe and the sand inlet.

[0020] Optionally, the blowing mechanism further includes a second air supply line, the two ends of which are respectively connected to the gas generator and the positive pressure regulating branch.

[0021] Optionally, the core box includes a left mold and a right mold that interlock with each other, and the left mold and the right mold together enclose the cavity.

[0022] Optionally, the core-making machine further includes an ejection mechanism, which includes a top plate, an ejector rod, and a guide structure. The ejector rod and the guide structure are disposed within the sealing cover, and the top plate is disposed within the cavity. The ejector rod is connected to the top plate and the guide structure respectively, and the top plate is used to push against the sand core for demolding.

[0023] On the other hand, the present invention provides a method for controlling the sand-shooting and curing process, applicable to the core-making machine in any of the above-mentioned solutions, the operation steps of which include:

[0024] S101, The sand-shooting mechanism moves to the top of the core box and presses the core box tightly;

[0025] S102. Open the first valve assembly, and the sand injection mechanism injects molding sand into the cavity of the core box. During sand injection, the airflow carries the molding sand into the cavity, and the exhaust regulating branch discharges the gas in the cavity.

[0026] S103. When the core injection amount reaches the predetermined value, open the second valve assembly and vacuum device. The vacuum device creates negative pressure in the area near the air hole of the core box. The molding sand moves towards this area and is compacted. The molding sand in each position in the cavity is compacted to form a sand core.

[0027] S104. Close the second valve assembly and vacuum device;

[0028] S105, The air blowing plate of the air blowing mechanism moves to the top of the core box and presses the core box tightly;

[0029] S106. Turn on the gas generator. The gas generator produces triethylamine gas. Part of the triethylamine gas enters the mold cavity through the sand inlet at the top of the core box through the first gas supply line and the blowing chamber and comes into contact with the sand core. The remaining part of the triethylamine gas enters the mold cavity through the air hole on the side wall of the core box through the second gas supply line, the positive pressure regulating branch and the exhaust chamber and comes into contact with the sand core. After blowing and curing, the core making is completed.

[0030] S107, The ejection mechanism removes the cured sand core from the mold cavity.

[0031] The beneficial effects of this invention are as follows:

[0032] This invention provides a core-making machine. The core box of the machine has a sealing cover circumferentially connected to the mold cavity on its side wall. Each sealing cover is connected to a corresponding control system, and at least two sealing covers and control systems are provided. During sand injection, the exhaust regulating branch of the control system controls the exhaust volume in sections to avoid excessive pressure drop during sand injection and low pressure at the far end of the injection port. Simultaneously, the negative pressure regulating branch of the control system adjusts the vacuum degree (pressure reduction) within the mold cavity, thereby increasing the pressure difference between this area and other areas, improving the fluidity of the molding sand, and facilitating compaction of the molding sand, resulting in good core-making effect. During the curing blowing process, the blowing mechanism can simultaneously blow triethylamine gas into the mold cavity through the sand inlet at the top of the core box and the positive pressure regulating branch on the side, achieving the optimal curing air intake combination. This significantly increases the air intake area, shortens the curing time, and improves curing efficiency. At the same time, the exhaust regulating branch can also increase its opening to increase the exhaust volume of the corresponding section, ensuring smooth air intake.

[0033] This embodiment also provides a sand-shooting and curing process control method, which is applied to the above-mentioned core-making machine. Through the above-mentioned sand-shooting and curing process control method, the sand cores produced can be compacted, with good appearance and strength, while the core-making efficiency is improved. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the core-making machine provided in an embodiment of the present invention;

[0036] Figure 2 This is a partial enlarged view of the core-making machine provided in an embodiment of the present invention.

[0037] In the picture:

[0038] 10. Sand core;

[0039] 100. Core box; 101. Cavity; 102. Sand inlet; 103. Air vent; 110. Left mold; 120. Right mold; 130. Vent plug;

[0040] 200. Sealing cover; 201. Exhaust port; 202. Exhaust chamber;

[0041] 300. Control system; 310. Exhaust regulating branch; 311. First manual valve; 312. First solenoid valve; 320. Negative pressure regulating branch; 321. Vacuum device; 322. Second manual valve; 323. Second solenoid valve; 324. First vacuum valve; 330. Positive pressure regulating branch; 331. Third manual valve; 332. Third solenoid valve; 333. Second vacuum valve;

[0042] 400. Ejection mechanism; 410. Ejector rod; 420. Guide structure;

[0043] 500. Air blowing plate. Detailed Implementation

[0044] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions 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.

[0045] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions. Furthermore, "above," "on top of," and "over" the first feature in relation to the second feature includes the first feature directly above and diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "under," and "below" the first feature in relation to the second feature includes the first feature directly below and diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0046] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0047] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0048] When using a vertical mold for core making, traditional core-making machines typically inject sand through the injection port (amine inlet) at the top of the mold, and then blow air through the amine inlet for curing. During the core-making process, since both the vertical mold injection port and the air-blowing curing amine inlet are formed through the upper core box structure of the mold, the area of ​​the air-blowing curing amine inlet formed by the upper core box generally accounts for less than 2% of the cavity area, resulting in long air-blowing curing time and low core-making efficiency. Furthermore, during sand injection, a small venting area is often arranged in the upper part of the side mold (near the injection port area) to avoid excessive pressure drop during sand injection, resulting in low pressure at the far end of the injection port and inability to compact the molding sand. During curing, which relies on the amine inlet for air-blowing curing, if the venting area near the amine inlet area is small, the curing agent (triethylamine gas) cannot effectively reach the core with the compressed air, resulting in poor core curing and a long air-blowing curing time. Therefore, the venting area required during sand shooting is small, while the venting area required during air blowing and solidification is large. This creates a contradiction, making it impossible to produce high-quality sand cores and resulting in low core-making efficiency.

[0049] Therefore, this embodiment provides a core-making machine, such as... Figure 1 and Figure 2 As shown, the core-making machine includes a core box 100, the interior of which is hollow to form a cavity 101. The top of the core box 100 is provided with a sand inlet 102 that communicates with the cavity 101. The sand inlet 102 is selectively connected to a sand-shooting mechanism or an air-blowing mechanism. When the sand inlet 102 is connected to the sand-shooting mechanism, the sand-shooting mechanism can inject molding sand into the cavity 101 through the sand inlet 102. When the sand inlet 102 is connected to the air-blowing mechanism, the air-blowing mechanism can blow triethylamine gas into the cavity 101 through the sand inlet 102. After the molding sand comes into contact with the triethylamine gas, it solidifies to form a sand core 10.

[0050] The sand making machine in this embodiment also includes a sealing cover 200 disposed circumferentially on the side wall of the core box 100. Each sealing cover 200 corresponds one-to-one with a control system 300, and at least two sealing covers 200 and control systems 300 are provided. Exemplarily, this embodiment uses four sealing covers 200 and four control systems 300 as an example. The four sealing covers 200 are divided into upper and lower layers, with two sealing covers 200 in each layer symmetrically disposed circumferentially on the side wall of the core box 100. Each sealing cover 200 is provided with an exhaust port 201. The sealing cover 200 and the side wall of the core box 100 enclose an exhaust chamber 202. One end of the exhaust chamber 202 communicates with the cavity 101, and the other end of the exhaust chamber 202 communicates with the exhaust port 201. Furthermore, each control system 300 includes an exhaust regulating branch 310, a negative pressure regulating branch 320, and a positive pressure regulating branch 330. The three branches of each control system 300 are connected to the same exhaust port 201. The exhaust regulating branch 310 is used to regulate the exhaust volume of the cavity 101, the negative pressure regulating branch 320 is used to regulate the vacuum degree in the cavity 101, and the positive pressure regulating branch 330 is connected to the blowing mechanism and is used to regulate the amount of amine introduced into the blowing mechanism.

[0051] Specifically, during the core-making process, the cavity 101 is divided into four venting zones, with each venting adjustment branch 310 corresponding to one venting zone. When the sand-shooting mechanism injects molding sand into the cavity 101, the air in the cavity 101 can be discharged sequentially through the venting chamber 202, venting interface 201, and venting adjustment branch 310 of the corresponding venting zone. On the one hand, since the cavity 101 in this embodiment is connected to four venting adjustment branches 310, and two venting interfaces 201 are respectively provided on the upper and lower layers of the core box 100, the venting zones are evenly distributed, which facilitates the venting of each venting zone and helps to make the molding sand in each position in the cavity 101 accumulate tightly. On the other hand, since the pressure in each venting zone is different, the venting volume during sand-shooting can be controlled by the venting adjustment branch 310 connected to the corresponding venting zone, so as to adjust the venting situation as needed.

[0052] For example, to maintain a constant pressure within the cavity 101 of the core box 100, the venting volume in the upper layer of the core box 100 (near the sand inlet 102) is typically reduced via the venting regulating branch 310 to avoid excessive sand injection pressure drop and low pressure at the far end of the injection port. However, the molding sand at the bottom of the core box 100 may not be able to be properly injected (filled). In this case, the negative pressure regulating branch 320 of the control system 300 can address the problem of poor local sand injection molding within the cavity 101. Specifically, each venting zone is also connected to the same venting port 201, and each venting port 201 is connected to a negative pressure regulating branch 320. The negative pressure regulating branch 320 can adjust the vacuum degree (pressure reduction) of the corresponding venting zone within the cavity 101, thereby increasing the pressure difference between the venting zone and other areas, thus improving the fluidity of the molding sand, which is beneficial for compacting the molding sand and achieving a good core-making effect.

[0053] Furthermore, during the curing and blowing process, the blowing mechanism can blow triethylamine gas into the cavity 101 through the sand inlet 102 at the top of the core box 100. At the same time, the blowing mechanism can also blow triethylamine gas into the cavity 101 through the positive pressure regulating branch 330, the exhaust port 201, and the exhaust chamber 202 on the side of the core box 100. On the one hand, the cavity 101 is connected to four positive pressure regulating branches 330, and the blowing mechanism simultaneously introduces amine gas from the top and side of the core box 100, achieving the optimal curing air intake combination, significantly increasing the air intake area, shortening the curing time, and improving the curing efficiency. On the other hand, the positive pressure regulating branch 330 can also adjust the amount of amine introduced by the blowing mechanism, and the exhaust regulating branch 310 can also increase its opening to increase the exhaust volume of the corresponding zone and ensure smooth air intake.

[0054] As an alternative, one end of the exhaust regulating branch 310 is connected to the exhaust port 201. The exhaust regulating branch 310 is equipped with a first valve assembly, and the exhaust volume of the cavity 101 can be adjusted by controlling the opening degree of the first valve assembly. The negative pressure regulating branch 320 is equipped with a vacuum device 321 and a second valve assembly. One end of the negative pressure regulating branch 320 is connected to the exhaust port 201. The vacuum device 321 is used to create a vacuum condition. The vacuum degree in the cavity 101 can be adjusted by controlling the opening degree of the second valve assembly. One end of the positive pressure regulating branch 330 is connected to the exhaust port 201. The positive pressure regulating branch 330 is equipped with a third valve assembly, and the amount of amine introduced by the blowing mechanism can be adjusted by controlling the opening degree of the third valve assembly.

[0055] For example, the first valve assembly includes a first manual valve 311 and a first solenoid valve 312, with the first manual valve 311 located upstream of the first solenoid valve 312, i.e., the first manual valve 311 is located at the end near the exhaust port 201; the second valve assembly includes a second manual valve 322, a second solenoid valve 323, and a first vacuum valve 324, with the first vacuum valve 324 located upstream of the second manual valve 322, the second manual valve 322 located upstream of the vacuum device 321, and the second solenoid valve 323 located downstream of the vacuum device 321, i.e., the first vacuum valve 324 is located at the end closest to the exhaust port 201; the third valve assembly includes a third manual valve 331, a third solenoid valve 332, and a second vacuum valve 333, with the second vacuum valve 333 located upstream of the third manual valve 331, and the third manual valve 331 located upstream of the third solenoid valve 332, i.e., the second vacuum valve 333 is located at the end near the exhaust port 201.

[0056] It should be noted that the control system 300 also includes a control device (not shown in the figure). The control device is communicatively connected to the first solenoid valve 312, the second solenoid valve 323, and the third solenoid valve 332. The control device can control the opening and closing of the first solenoid valve 312, the second solenoid valve 323, and the third solenoid valve 332, and adjust the opening degree of the first solenoid valve 312, the second solenoid valve 323, and the third solenoid valve 332. In this embodiment, the control device can be a centralized or distributed controller. For example, the controller can be a single microcontroller or a combination of multiple distributed microcontrollers. The microcontroller can run a control program to control the first solenoid valve 312, the second solenoid valve 323, and the third solenoid valve 332 to achieve their functions. In addition, the first manual valve 311, the second manual valve 322 and the third manual valve 331 are provided as backups. When the first solenoid valve 312, the second solenoid valve 323 and the third solenoid valve 332 become uncontrollable or are damaged, they can be adjusted separately by the first manual valve 311, the second manual valve 322 and the third manual valve 331, thereby ensuring the reliability of the adjustment system.

[0057] See also Figure 2The venting chamber 202 is connected to the molding cavity 101 through vent holes 103 provided on the side wall of the core box 100. Each venting chamber 202 can be provided with multiple vent holes 103, thereby increasing the venting area or the amine inlet area, and also improving the uniformity of venting or amine inlet. Further, vent plugs 130 are embedded in the side wall of the core box 100. Each vent plug 130 is provided with one vent hole 103. The vent plug 130 is configured to allow gas to pass through, but not molding sand, thereby sealing the vent hole 103 and preventing molding sand from entering the venting chamber 202. Optionally, in this embodiment, each venting chamber 202 is provided with three vent holes 103 and three vent plugs 130 as an example. Of course, in other embodiments, each venting chamber 202 can also be provided with other numbers of vent holes 103 and vent plugs 130, as long as the vent holes 103 and vent plugs 130 correspond one-to-one, which is not limited here.

[0058] Optionally, the blowing mechanism includes a gas generator, a first gas supply pipe, and a blowing plate 500. The first gas supply pipe is connected to the gas generator, which generates triethylamine gas. During curing blowing, the blowing plate 500 moves to the top of the core box 100 and forms a blowing chamber with the top wall of the core box 100. The blowing chamber is connected to the first gas supply pipe and the sand inlet 102, allowing the triethylamine gas to contact the molding sand at the top of the cavity 101 after passing through the first gas supply pipe, the blowing chamber, and the sand inlet 102. Additionally, the blowing mechanism includes a second gas supply pipe, with its two ends connected to the gas generator and the positive pressure regulating branch 330, respectively. This allows the triethylamine gas to contact the molding sand inside the cavity 101 after passing through the second gas supply pipe, the positive pressure regulating branch 330, the exhaust chamber 202, and the vent 103, thereby increasing the amine inlet area and improving curing efficiency. In addition, when the air hole 103 on the side wall of the core box 100 is blocked, a larger pressure gas can be introduced into the cavity 101 through the positive pressure regulating branch 330 to blow off the molding sand blocking the air hole 103 and ensure smooth airflow between the cavity 101 and the exhaust chamber 202.

[0059] See also Figure 1 In this embodiment, the core box 100 includes a left mold 110 and a right mold 120 that interlock with each other, and the left mold 110 and the right mold 120 together form a cavity 101. The left mold 110 and the right mold 120 are each provided with two sealing covers 200, and the two sealing covers 200 are stacked on top of each other. By setting the core box 100 in this way, it is convenient to remove it after the molding sand has solidified into a sand core 10.

[0060] Optionally, the core-making machine also includes an ejection mechanism 400, which assists in demolding the sand core 10. Specifically, the ejection mechanism 400 includes a top plate, an ejector rod 410, and a guide structure 420. The ejector rod 410 and the guide structure 420 are disposed within the sealing cover 200, and the top plate is disposed within the cavity 101 (not shown in the figure). The ejector rod 410 is connected to the top plate and the guide structure 420 respectively. The guide structure 420 provides guidance for the ejector rod 410. The ejector rod 410 pushes the top plate to move radially along the sand core 10 so that the top plate abuts against the sand core 10, thereby assisting in demolding the sand core 10.

[0061] This embodiment also provides a method for controlling the sand-shooting and curing process, applied to the aforementioned core-making machine, and the operation steps include:

[0062] S101, The sand-shooting mechanism moves to the top of the core box 100 and presses the core box 100;

[0063] S102. Open the first valve assembly, and the sand-shooting mechanism injects molding sand into the cavity 101 of the core box 100. During sand-shooting, the airflow carries the molding sand into the cavity 101, and the exhaust regulating branch 310 discharges the gas in the cavity 101. The exhaust volume of the cavity 101 can be adjusted by adjusting the opening of the first valve assembly. For example, during sand-shooting, the opening of the first valve assembly on the two exhaust regulating branches 310 located in the upper layer can be appropriately reduced to reduce the exhaust volume in the upper layer of the cavity 101, which helps to reduce the pressure drop during sand-shooting and make the injection distance of the molding sand farther.

[0064] S103 When the core injection amount reaches the predetermined value (for example, the sand injection amount reaches 80%-90% of the total molding sand amount), the second valve assembly and vacuum device 321 are opened. The vacuum device 321 forms a negative pressure in the area near the vent 103 of the core box 100. The molding sand moves towards this area and is compacted. The molding sand in each position in the cavity 101 is compacted to form the sand core 10. This ensures that the molding sand is filled tightly and the core making effect is good, avoiding the sand core 10 from falling off during the subsequent casting process.

[0065] S104. Close the second valve assembly and vacuum device 321;

[0066] S105, the air blowing plate 500 of the air blowing mechanism moves to the top of the core box 100 and presses the core box 100;

[0067] S106. Turn on the gas generator. The gas generator produces triethylamine gas. Part of the triethylamine gas enters the mold cavity 101 through the sand inlet 102 at the top of the core box 100 through the first gas supply pipe and the blowing chamber, and contacts the sand core 10. The remaining part of the triethylamine gas enters the mold cavity 101 through the air hole 103 on the side wall of the core box 100 through the second gas supply pipe, the positive pressure regulating branch 330 and the exhaust chamber 202, and contacts the sand core 10. After blowing and curing, the core making is completed.

[0068] During this process, triethylamine gas is introduced into the exhaust ports 201 of the four sealing covers 200 through the second air supply pipe, the positive pressure regulating branch 330, and the exhaust chamber 202 for curing. The amount of amine gas introduced can be adjusted by adjusting the opening of the third valve assembly on the positive pressure regulating branch 330. The blowing plate 500 blows triethylamine gas into the mold cavity 101 through the sand inlet 102, which greatly increases the amine inlet area, shortens the curing time, and improves the curing efficiency. Furthermore, since the amount of amine gas introduced is increased, the amount of gas discharged from the mold cavity 101 also needs to be increased. Therefore, it is necessary to increase the opening of the first valve assembly on the four exhaust regulating branches 310 in order to increase the exhaust volume of the mold cavity 101 and avoid excessive pressure on the core box 100.

[0069] S107, the ejection mechanism 400 demolds the cured sand core 10 from the cavity 101.

[0070] In summary, by using the above-mentioned sand injection and curing process control methods, the resulting sand cores can be compacted, with good appearance and strength, while also improving core-making efficiency.

[0071] Obviously, the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

[0072] Note that in the description of this specification, the references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

Claims

1. A method for controlling the sand-shooting and curing process, characterized in that, Applied to a core-making machine, the core-making machine comprising: The core box (100) has a hollow interior forming a cavity (101). The top of the core box (100) is provided with a sand inlet (102) that communicates with the cavity (101). The sand inlet (102) is selectively connected to a sand-shooting mechanism or an air-blowing mechanism. At least two sealing covers (200) are disposed around the side wall of the core box (100), and each sealing cover (200) is provided with an exhaust port (201). The sealing cover (200) and the side wall of the core box (100) form an exhaust cavity (202), and the exhaust cavity (202) communicates with the cavity (101) and the exhaust port (201). The control system (300) corresponds one-to-one with the sealing cover (200). Each control system (300) includes an exhaust regulating branch (310), a negative pressure regulating branch (320), and a positive pressure regulating branch (330) that are connected to the exhaust port (201). The exhaust regulating branch (310) is used to regulate the exhaust volume of the cavity (101). The negative pressure regulating branch (320) is used to regulate the vacuum degree in the cavity (101). The positive pressure regulating branch (330) is connected to the blowing mechanism and is used to regulate the amount of amine introduced into the blowing mechanism. The exhaust regulating branch (310) is provided with a first valve assembly, and the exhaust volume of the cavity (101) is adjusted by controlling the opening degree of the first valve assembly; The negative pressure regulating branch (320) is provided with a vacuum device (321) and a second valve assembly. One end of the negative pressure regulating branch (320) is connected to the exhaust port (201). The vacuum device (321) is used to create a vacuum condition. The second valve assembly is used to regulate the vacuum level in the cavity (101). The positive pressure regulating branch (330) is provided with a third valve assembly, and the amount of amine fed into the blowing mechanism is adjusted by controlling the opening degree of the third valve assembly; The cavity (101) is provided with sealing covers (200) on both the top and bottom. The operation steps of the sandblasting and curing process control method include: S101, The sand-shooting mechanism moves to the top of the core box (100) and presses the core box (100) tightly; S102. Open the first valve assembly. The sand-shooting mechanism injects molding sand into the cavity (101) of the core box (100). During sand-shooting, the airflow carries the molding sand into the cavity (101), and the exhaust regulating branch (310) discharges the gas in the cavity (101). S103 When the core injection amount reaches the predetermined value, the second valve assembly and vacuum device (321) are opened. The vacuum device (321) forms a negative pressure in the area near the air hole (103) of the core box (100). The molding sand moves towards this area and is compacted. The molding sand in each position in the cavity (101) is compacted to form a sand core (10). S104. Close the second valve assembly and vacuum device (321); S105, the air blowing plate (500) of the air blowing mechanism moves to the top of the core box (100) and presses the core box (100) tightly; S106. Turn on the gas generator. The gas generator produces triethylamine gas. Part of the triethylamine gas enters the mold cavity (101) through the sand inlet (102) at the top of the core box (100) through the first gas supply line and the blowing chamber and comes into contact with the sand core (10). The remaining part of the triethylamine gas enters the mold cavity (101) through the air hole (103) on the side wall of the core box (100) through the second gas supply line, the positive pressure regulating branch (330) and the exhaust chamber (202) and comes into contact with the sand core (10). After blowing and solidification, the core making is completed. S107, the ejection mechanism (400) demolds the cured sand core (10) from the cavity (101).

2. The sand-shooting and curing process control method according to claim 1, characterized in that, The first valve assembly includes a first manual valve (311) and a first solenoid valve (312), wherein the first manual valve (311) is disposed upstream of the first solenoid valve (312); The second valve assembly includes a second manual valve (322), a second solenoid valve (323), and a first vacuum valve (324). The first vacuum valve (324) is located upstream of the second manual valve (322), the second manual valve (322) is located upstream of the vacuum device (321), and the second solenoid valve (323) is located downstream of the vacuum device (321). The third valve assembly includes a third manual valve (331), a third solenoid valve (332), and a second vacuum valve (333), wherein the second vacuum valve (333) is located upstream of the third manual valve (331), and the third manual valve (331) is located upstream of the third solenoid valve (332).

3. The method for controlling the sand-shooting and curing process according to claim 1, characterized in that, The exhaust chamber (202) is connected to the cavity (101) through air holes (103) provided on the side wall of the core box (100), and each exhaust chamber (202) is provided with a plurality of air holes (103).

4. The sand-shooting and curing process control method according to claim 3, characterized in that, An exhaust plug (130) is embedded in the side wall of the core box (100). The exhaust plug (130) is used to block the air hole (103). The exhaust plug (130) is configured to allow gas to pass through.

5. The method for controlling the sand-shooting and curing process according to claim 1, characterized in that, The blowing mechanism includes a gas generator, a first air supply pipe and an air blowing plate (500). The first air supply pipe is connected to the gas generator. The air blowing plate (500) and the top wall of the core box (100) form an air blowing chamber. The air blowing chamber is connected to the first air supply pipe and the sand inlet (102).

6. The method for controlling the sand-shooting and curing process according to claim 5, characterized in that, The blowing mechanism also includes a second air supply line, the two ends of which are respectively connected to the gas generator and the positive pressure regulating branch (330).

7. The method for controlling the sand-shooting and curing process according to any one of claims 1-6, characterized in that, The core box (100) includes a left mold (110) and a right mold (120) that interlock with each other, and the left mold (110) and the right mold (120) together form the cavity (101).

8. The method for controlling the sand-shooting and curing process according to any one of claims 1-6, characterized in that, The core-making machine also includes an ejection mechanism (400), which includes a top plate, an ejector rod (410), and a guide structure (420). The ejector rod (410) and the guide structure (420) are disposed inside the sealing cover (200), and the top plate is disposed inside the cavity (101). The ejector rod (410) is connected to the top plate and the guide structure (420) respectively. The top plate is used to push against the sand core (10) for demolding.

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