Sand mold manufacturing method, casting product manufacturing method, and sand mold manufacturing support system

Abstract

Maintain a consistent hardening rate for sand molds, thereby improving the quality of both the sand molds and the cast products. [Solution] The method for manufacturing a sand mold includes a step S22 to confirm whether or not to use a chill in the sand mold, and a step S23 to determine the mixing ratio of the hardener, binder, and diluent to the self-hardening sand, such that if a chill is used, the mixing ratio of at least one of the hardener, binder, and diluent mixed into the self-hardening sand is changed compared to when a chill is not used. By performing the above steps, the variation in the hardening speed of the sand mold due to the use or non-use of a chill can be suppressed, thereby improving the quality of the sand mold.

Description

Technical Field

[0005]

[0001] The present disclosure relates to a method for manufacturing a sand mold, a method for manufacturing a casting product, and a sand mold manufacturing support system.

Background Art

[0002] In sand casting, sand is pressed against a product mold to manufacture a sand mold, and molten metal is poured into this sand mold for casting. The molten metal is called molten metal. At this time, if the collapsed sand mold or gas derived from the sand mold混入 the product, it will result in poor quality. In order to prevent defects, it is important to ensure sufficient strength during sand mold molding.

[0003] Among sand casting, for the production of medium to large-sized casting products, a sand mold using self-hardening sand with high strength is used. This is to mix a binder and a curing agent into the sand, knead it with a mixer, then press it against the product mold, and after the binder has hardened after a certain period of time, remove it from the mold to obtain the sand mold. Here, since the curing speed is greatly affected by temperature, it is necessary to control the composition of the binder and the curing agent according to the temperature and make the curing time constant.

[0004] So far, an apparatus for automatically adjusting the chemical agent formulation has been proposed to suppress fluctuations in the curing time. For example, Japanese Patent No. 7145130 (Patent Document 1) discloses a casting support system that provides recommended information on the composition and supply amount of a curing agent and a binder in consideration of, in addition to the temperature of sand, i.e., refractory particles, the proportion of recycled sand among the refractory particles, the acid consumption of the refractory particles, and the environmental temperature and humidity of the casting factory.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The inventors' research revealed that the quality of a sand mold is influenced by factors such as the material of the model used in its manufacture, the model's temperature, and the presence or absence of a chill. However, the casting support system disclosed in Japanese Patent Publication No. 7145130 (Patent Document 1) only considers environmental information such as refractory particles (i.e., the properties of the sand), ambient temperature, and humidity during casting, and does not consider the presence or absence of a chill, nor the materials and temperatures of the model, base plate, and mold. In other words, conventional methods do not consider the material of the model used in its manufacture, the model's temperature, or the presence or absence of a chill, leaving room for improvement in the quality of the sand mold and, consequently, the quality of the cast product.

[0007] This disclosure aims to solve these problems by changing the temperature of the chill or the composition of binders, hardeners, etc. used during sand mold manufacturing, taking into account the material or temperature of the model used when manufacturing the sand mold, or the presence or absence of a chill, thereby maintaining a constant hardening rate of the sand mold and improving the quality of the sand mold and the cast product. [Means for solving the problem]

[0008] This disclosure relates to a method for manufacturing a sand mold for casting using self-hardening sand. The sand mold manufacturing method comprises the steps of: confirming whether or not to use a chill in the sand mold; and, if a chill is used, determining the mixing ratio of the hardener, binder and diluent to the self-hardening sand such that the mixing ratio of at least one of the hardener, binder and diluent mixed into the self-hardening sand is changed compared to when a chill is not used.

[0009] A method for manufacturing a sand mold for casting using self-hardening sand, according to other aspects of this disclosure, comprises the steps of: confirming at least one of the material for the model and the material for the base plate used in manufacturing the sand mold; and determining the mixing ratio of at least one of the hardener, binder, and diluent to be mixed into the self-hardening sand based on the confirmed material for the model and the material for the base plate. [Effects of the Invention]

[0010] The sand mold manufacturing method of this disclosure can suppress fluctuations in the hardening rate of the sand mold and improve the quality of the sand mold and the quality of the cast product. [Brief explanation of the drawing]

[0011] [Figure 1] This is a schematic diagram illustrating the outline of the sand mold manufacturing process according to Embodiment 1. [Figure 2] This is a flowchart illustrating a method for changing the drug formulation ratio according to Embodiment 1. [Figure 3] This is a flowchart illustrating a method for changing the drug formulation ratio according to Embodiment 2. [Figure 4] This is a schematic diagram illustrating the outline of a sand mold manufacturing process that includes a step of heating a chilling plate according to Embodiment 3. [Figure 5] This is a schematic diagram illustrating the outline of a sand mold manufacturing process that includes a step of heating a chiller according to Embodiment 4. [Figure 6] This is a flowchart illustrating the method for manufacturing a sand mold according to Embodiment 5. [Figure 7] This is a flowchart illustrating a method for changing the drug formulation ratio according to Embodiment 6. [Figure 8] This is a schematic diagram illustrating the outline of a sand mold manufacturing process using a sand mold manufacturing support system that changes the drug formulation ratio according to Embodiment 7. [Figure 9] This is a block diagram showing the configuration of the manufacturing support system and controller. [Figure 10] This is a schematic diagram illustrating the outline of a sand mold manufacturing process using a sand mold manufacturing support system that changes the drug formulation ratio according to Embodiment 8. [Figure 11] This is a schematic diagram illustrating the outline of a sand mold manufacturing process using a sand mold manufacturing support system that changes the drug formulation ratio according to Embodiment 9. [Figure 12] This is a schematic diagram illustrating the outline of a sand mold manufacturing process using a sand mold manufacturing support system that changes the drug formulation ratio according to Embodiment 10. [Figure 13]It is a schematic diagram showing an outline of a sand mold manufacturing process using a sand mold manufacturing support system for changing the drug mixing ratio according to Embodiment 11. [Figure 14] It is a schematic diagram showing an outline of a sand mold manufacturing process using a sand mold manufacturing support system for changing the drug mixing ratio according to Embodiment 12. [Figure 15] It is a schematic diagram showing an outline of a sand mold manufacturing process using a sand mold manufacturing support system for changing the drug mixing ratio according to Embodiment 13. [Figure 16] It is a schematic diagram showing an outline of a sand mold manufacturing process using a sand mold manufacturing support system for changing the drug mixing ratio according to Embodiment 14. [Figure 17] It is a diagram showing an example of the configuration of a learning device included in a sand mold manufacturing support system according to Embodiment 15. [Figure 18] It is a diagram conceptually showing the configuration of a neural network included in a sand mold manufacturing support system according to Embodiment 15. [Figure 19] It is a flowchart showing a part of the processing of a learning device included in a sand mold manufacturing support system according to Embodiment 15. [Figure 20] It is a diagram showing an example of the configuration of an inference device included in a sand mold manufacturing support system according to Embodiment 15. [Figure 21] It is a flowchart showing a part of the processing of an inference device included in a sand mold manufacturing support system according to Embodiment 15.

Embodiments for Carrying Out the Invention

[0014] First, in process S1, the chilling iron 13 and the metal frame 11 are placed on a surface plate 10 on which a model 12, which mimics the shape of the product, is pre-attached. The metal frame 11 is also called the casting frame.

[0015] Next, in step S2, the binder, hardener, and diluent are mixed in the mixer 24 and poured into the metal frame 11, while the worker compacts it with their hands and feet to manufacture the sand mold. This process is also called molding. At this time, the controller 20 controls the binder supply unit 21, the hardener supply unit 22, and the diluent supply unit 23 based on the output of the sand temperature sensor 25 or the operator's button operation, to determine the amount of each binder, hardener, and diluent to be added.

[0016] Next, in step S3, after the binder has hardened, the model is removed from the sand mold. This step is called mold removal. Then, in step S4, a slurry called mold coating is applied to protect the surface of the sand mold and prevent gases generated from the sand mold from entering the product, and the mold is dried in a furnace.

[0017] Next, the upper mold 30 and the lower mold 31 are molded, cut, coated, and dried, and then in process S5, the upper mold 30 and the lower mold 31 are joined together. After that, the completed sand mold is sent to the pouring process, where molten metal is poured into the internal cavity.

[0018] In process S6, after the molten metal has cooled and solidified, the sand mold is dismantled and the cast product 40 is removed. After the product is removed, in process S7, the metal frame 11 and chill 13 are recovered and reused.

[0019] Furthermore, the sand molds are dismantled and crushed, and the binder is removed in the sand regeneration process in step S8 to produce recycled sand. In the sand regeneration process, worn-out sand is removed, reducing the total amount, so in step S9, the recycled sand is replenished with new sand. This is called new sand.

[0020] The process shown here is a typical sand mold manufacturing process, but the details vary depending on the casting product and the foundry. For example, depending on the required quality of the product, chill plates 13 may not be used. Also, while this example shows the use of three types of chemicals—binder, hardener, and diluent—some factories adjust the hardening speed by using two or more types of hardeners with different hardening speeds without using a diluent. Furthermore, some factories do not pre-attach the model 12 to the base plate 10, but instead install it for each molding. Some factories integrate the metal frame 11 and the base plate 10, and remove the metal frame along with the model and base plate when removing them from the sand mold.

[0021] Furthermore, in foundries that do not operate continuously day and night, but only during the day, the sand molds, after being removed and poured, are often dismantled the following day.

[0022] In this case, immediately after dismantling, the sand mold maintains a temperature of over 100°C in the areas in contact with the product. Therefore, if the sand is recycled and reused on the day of dismantling, it will be used while still at a high temperature. On the other hand, if a large amount of sand is stored and the sand is used the day after dismantling, the sand temperature will drop to almost the same level as the ambient temperature.

[0023] Furthermore, chills and molds, when used immediately after being removed from the sand mold or product, are at a high temperature of nearly 100°C, while when used the day after dismantling or later, their temperature drops to almost the same as the ambient temperature. Thus, the temperature at which sand, chills, and molds are used varies depending on the time elapsed between their initial use and reuse, and it is possible that the temperatures of the sand, chills, and molds themselves may be completely different.

[0024] As mentioned earlier, the exothermic curing reaction of the binder causes the temperature inside the sand mold to rise by about 5-10°C from before mixing. On the other hand, because chills have a large heat capacity per unit volume, the temperature of the sand in contact with the chill surface tends to decrease compared to the inside of the sand mold. Furthermore, because chills are heavy, if the sand near the chill is not sufficiently cured when removing the model from the sand mold, the chill will fall. To prevent this, when using chills, it is necessary to increase the curing speed of the sand and shorten the time required for complete curing compared to when chills are not used.

[0025] In process S2, automatic control of the chemical mixture according to the sand temperature measured by the sand temperature sensor 25 is widely implemented in many foundries. However, automatic control alone cannot maintain a constant sand hardening rate, and manual adjustment of the mixture is necessary. Since the method of adjustment relies heavily on the know-how of the workers, there is a large amount of variation depending on the person, and the judgment criteria are not clear, which can lead to poor quality sand molds and, consequently, poor quality cast products using those sand molds.

[0026] The inventors investigated situations where manual adjustment of the mixture was necessary when automatically controlling the chemical mixture according to the sand temperature, and also investigated the quality of the manufactured sand molds and the conditions during manufacturing. As a result, it became clear that even under the same sand and environmental conditions, the hardening rate of the sand differed depending on the model and metal frame used in sand mold manufacturing.

[0027] The sand used to manufacture the sand mold is reused after pouring in process S5 and casting, followed by a regeneration process in process S8. During this process, the parts that come into contact with the molten metal become hot, and heat is generated by friction when removing the binder remaining on the surface during the regeneration process. Therefore, after the regeneration process in process S8, the foundry sand is cooled through a cooling process, but depending on the capacity of the cooler and the amount of foundry sand used, it is often reused at a temperature about 10-20°C higher than room temperature. On the other hand, the model 12 used for casting is at almost room temperature, so its temperature is lower than that of the reused sand. It was thought that the temperature of the sand in contact with the model 12 decreased, slowing down the hardening rate, resulting in insufficient hardening of the sand mold and a decrease in quality.

[0028] Further investigation revealed the influence of the model material and the auxiliary materials attached to the model. While wood, resin, and metal are used for the model and the mounting plate, metal, in particular, has a high heat capacity and therefore significantly impacts the sand mold's hardening rate. Additionally, for some castings, a metal plate called a chill is embedded in the sand mold to control the cooling rate of the molten metal. This metal plate, like the model, is at approximately room temperature and also has a high heat capacity. Therefore, it was estimated to have a significant impact on the sand's hardening rate.

[0029] As mentioned above, several factors can contribute to a decrease in the quality of sand molds. In Embodiment 1, the presence or absence of a chill is considered in the mixing ratio of chemicals such as binders, hardeners, and diluents. Figure 2 is a flowchart illustrating the sand mold manufacturing method according to Embodiment 1. The process in this flowchart is introduced in step S2 of Figure 1.

[0030] When molding begins, in step S21, the chemical mixture ratio is first set to a ratio corresponding to the standard curing speed, taking into account the sand temperature. Then, in step S22, it is determined whether or not a chill is used for the sand mold to be molded.

[0031] If a chiller is used (YES in S22), the drug mixture ratio is changed in step S23, and molding is performed in step S24. On the other hand, if a chiller is not used (NO in S22), step S23 is not performed, and molding is performed in step S24 with the standard drug mixture ratio set in step S21.

[0032] In step S22, the presence or absence of a chilling plate is checked. If a chilling plate is used, the mixing ratio of the hardener, binder, and diluent is changed in step S23 to increase the curing speed. However, there are no limitations on which chemicals to adjust, and several adjustment methods are possible. For example, if a diluent is used, the curing speed can be increased by reducing the amount of diluent. If multiple hardeners with different curing speeds are used, the curing speed can be increased by reducing the proportion of the slow-curing hardener and increasing the proportion of the fast-curing hardener. The curing speed can also be increased by reducing the proportion of the binder, but this may reduce the strength of the sand mold after curing, which is undesirable.

[0033] Many foundries have controllers installed on their molding lines to automatically control the chemical mixture according to the sand temperature. These controllers typically also have a switch for manually adjusting the curing speed. If the operator adjusts the curing speed using this switch depending on whether a chill is present or not in steps S22 and S23, the calculation of the chemical mixture becomes unnecessary, reducing the operator's workload. Alternatively, steps S22 and S23 may be automated by the controller.

[0034] Embodiment 2. In Embodiment 2, the materials of the model and surface plate are considered. As mentioned above, when a chill is embedded in the sand mold, the hardening rate of the sand near the chill decreases, but the hardening rate of the sand mold is also affected by the model and surface plate used for molding. Wood, resin, and metal are used as materials for the model and surface plate. Here, metal has a higher thermal conductivity and a larger heat capacity per unit volume compared to wood and resin. Therefore, the part of the sand mold that is in contact with a metal model or surface plate loses heat to the model and surface plate, causing the temperature to drop compared to other parts and reducing the hardening rate. In Embodiment 2, the materials of the model and surface plate are checked, and if a metal model or metal surface plate is used, the mixing ratio of the hardener, binder, and diluent is changed to increase the hardening rate.

[0035] Figure 3 is a flowchart illustrating the method for manufacturing a sand mold according to Embodiment 2. The process in this flowchart is introduced into step S2 in Figure 1.

[0036] When molding begins, in step S31, the chemical mixture ratio is first set to a ratio corresponding to the standard curing speed, taking into account the sand temperature. Then, in step S32, it is determined whether the material of the base plate for the sand mold to be molded is metal or not.

[0037] If the surface plate is made of metal (YES in S32), the chemical mixture ratio is changed in step S33. In this case, the chemical mixture ratio is changed to increase the curing speed beyond the standard. On the other hand, if the surface plate is not made of metal (NO in S32), step S33 is not performed, and the process proceeds to step S34 with the standard chemical mixture ratio set in step S31.

[0038] In step S34, it is determined whether the material of the sand mold to be created is metal or not. If the material of the model is metal (YES in S34), the chemical mixture ratio is changed in step S35. In this case, the chemical mixture ratio is changed to increase the curing speed beyond the standard. On the other hand, if the material of the model is not metal (NO in S34), step S35 is not performed, and the process proceeds to step S36.

[0039] In step S36, molding is performed using sand with the chemical mixture ratio determined by the processes in S31 to S35.

[0040] Thus, in Embodiment 2, after checking the materials of the model and surface plate, if a metal model or metal surface plate is used, the mixing ratio of the hardener, binder, and diluent is changed to increase the curing speed. The choice of which chemicals to adjust is not limited. For example, if a diluent is used, the curing speed can be increased by reducing the amount of the diluent. If multiple hardeners with different curing speeds are used, the proportion of the slow-curing hardener is reduced and the proportion of the fast-curing hardener is increased. The curing speed can also be increased by reducing the proportion of the binder, but this may reduce the strength of the sand mold after curing, which is undesirable.

[0041] Many foundries have controllers installed on their molding lines to automatically control the chemical mixture according to the sand temperature. These controllers typically also have a switch for manually adjusting the curing speed. As shown in steps S32 to S35, by deciding whether or not to change the chemical mixture according to the material of the model and the base plate, and then adjusting the curing speed by operating this switch, the calculation of the chemical mixture becomes unnecessary, reducing the workload on the operator. Alternatively, the process in steps S32 to S35 may be performed automatically by the controller.

[0042] Embodiment 3. In Embodiment 3, the temperature of the chill is taken into consideration. Even if a sand mold is formed using sand cooled to the same temperature as the ambient temperature, the temperature inside the sand mold will rise by about 5 to 10°C from before mixing due to the exothermic curing reaction of the binder. Therefore, by heating the chill to a temperature higher than the ambient temperature before using it in the molding process, the temperature inside the sand mold during curing can be made uniform. In order to make the temperature inside the sand mold uniform, it is desirable to preheat the chill to a temperature about 5 to 10°C higher than the ambient temperature.

[0043] Figure 4 is a diagram illustrating the method for manufacturing a sand mold according to Embodiment 3. First, in step S41, the chiller 13 is heated. There are various methods for heating the chiller. For example, a commercially available refrigerator / warmer can be used, but since chillers have a large heat capacity and it takes time to heat them to the inside, it is desirable to heat them for more than two hours before molding. If there are only a few chillers and there is not enough time to heat them before molding, heating them in a water bath can shorten the heating time, but if moisture remains on the surface, it will inhibit the hardening of the binder, so it is necessary to wipe off any moisture thoroughly before use. Alternatively, induction heating or infrared heating may be used to heat the chiller. However, if the temperature of the chiller becomes higher than the temperature of the sand during hardening, the temperature distribution inside the sand mold will become uneven, so it is desirable to set the heating temperature so that it does not become more than 20°C higher than the temperature of the sand.

[0044] Next, in step S42, the model 12, the preheated chill plate 13, and the metal frame 11 are placed on the surface plate 10.

[0045] Next, in step S43, the binder, hardener, and diluent are mixed in the mixer 24 and poured into the metal frame 11, while the worker compacts it with their hands and feet to manufacture the sand mold. At this time, the controller 20 controls the binder supply unit 21, the hardener supply unit 22, and the diluent supply unit 23 based on the output of the sand temperature sensor 25, etc., to determine the amount of each binder, hardener, and diluent to be added. The subsequent steps are the same as steps S3 to S9 in Figure 1, so the explanation will not be repeated.

[0046] As described above, in Embodiment 3, by heating the chiller to a temperature higher than the ambient temperature before using it in the molding process, the temperature inside the sand mold during hardening can be made uniform. As a result, the sand mold can be hardened evenly.

[0047] Embodiment 4. In Embodiment 4, the temperature difference between the chill and the sand is taken into consideration. If the temperature difference between the chill and the sand is small, it is not necessary to heat the chill.

[0048] Figure 5 is a diagram illustrating the method for manufacturing a sand mold according to Embodiment 4. First, in step S51, the temperature of the sand used for molding is measured, and in step S52, the temperature of the chill or the ambient temperature is measured.

[0049] While there are no limitations on the method for measuring sand temperature, many foundries have a sand temperature sensor 25 installed in the sand hopper, which is connected to a chemical compounding controller 20. By displaying this temperature on a display unit 26, the need for additional equipment can be minimized.

[0050] Furthermore, there are no restrictions on the method of measuring the temperature of the chiller, but a contact thermometer or an infrared thermometer can be used. Also, since a chiller left for a long time can be considered to be at almost the same temperature as the ambient temperature, the temperature difference can be calculated by substituting the ambient temperature (air temperature) for the chiller temperature.

[0051] In the subsequent step S53, the temperature difference between the chiller and the sand is calculated, and the chiller is preheated and used only if the temperature difference exceeds a certain threshold.

[0052] Here, the temperature inside the sand mold rises by about 5-10°C from before mixing due to the exothermic hardening reaction of the binder. Therefore, when measuring the temperature of the sand, it is desirable to preheat the chill to a temperature about 5-10°C higher than the temperature of the sand.

[0053] Next, in step S54, the model 12, the preheated chill 13, and the metal frame 11 are placed on the surface plate 10. Then, in step S55, the binder, hardener, and diluent are mixed in the mixer 24 and poured into the metal frame 11, while the worker compacts it by stepping on it with their hands and feet to manufacture the sand mold. The subsequent steps are the same as steps S3 to S9 in Figure 1, so the explanation will not be repeated.

[0054] As described above, in Embodiment 4, by heating the chiller to a temperature slightly higher than the sand temperature before using it in the molding process, the temperature inside the sand mold during hardening can be made uniform. As a result, the sand mold can be hardened evenly.

[0055] Embodiment 5. Embodiment 5 describes a method for manufacturing a cast product, characterized by measuring the temperature of at least one of the chill plate, surface plate, model, and metal frame, and correcting the hardener formulation according to that temperature.

[0056] Figure 6 is a flowchart illustrating the method for manufacturing a sand mold according to Embodiment 5. The process in this flowchart is introduced into step S2 in Figure 1.

[0057] When molding begins, in step S51A, the temperature of the self-hardening sand used for the sand mold is measured as the first temperature, and the chemical mixture ratio is set to a ratio corresponding to the standard hardening speed corresponding to the sand temperature. Next, in step S52A, the temperature of the mold frame is measured, and the chemical mixture ratio is changed to reflect the temperature of the mold frame. Then, in step S53A, it is determined whether or not a chill is being used. If a chill is being used (YES in S53), in step S54A, the temperature of the chill is measured, and the chemical mixture ratio is changed to reflect the temperature of the chill, and the process proceeds to step S55A. On the other hand, if a chill is not being used (NO in S53A), the process in step S54A is not performed, and the process proceeds to the next step, S55A.

[0058] In step S55A, the temperature of the surface plate is measured, and the chemical mixture ratio is changed to reflect the surface plate temperature. Next, in step S56A, the temperature of the model is measured, and the chemical mixture ratio is changed to reflect the model temperature. Using the sand with the chemical mixture ratio determined in this way, molding is performed in step S57A.

[0059] By using the casting method described above, Embodiment 5 can more accurately reflect the influence that chills, metal models, metal base plates, and metal frames, which have high heat capacity, have on the temperature of the casting sand.

[0060] Here, the temperatures of the sand, metal frame, chill, surface plate, and model, as measured by each component, may be measured by an operator or by a mechanism that automatically acquires the data. Furthermore, the temperatures of the sand, metal frame, chill, metal model, and metal surface plate after being left for a long period of time after use can be considered to be approximately the same as the ambient temperature. Therefore, the ambient temperature may be measured and used as a substitute for the temperatures of the sand, metal frame, chill, metal model, and metal surface plate.

[0061] Regarding the chemical formulation information, the mixing ratios of the hardener, binder, and diluent to the sand may be directly specified to the controller, or information to correct the hardening speed may be input to the controller. Alternatively, the temperature of the sand around the model may be predicted, and information to correct the temperature of the sand used for adjusting the hardener formulation may be sent to the controller.

[0062] Embodiment 6. Embodiment 6 describes a method for manufacturing a cast product, characterized by measuring the temperature of at least one of the chill, surface plate, model, and metal frame, and correcting the hardener composition according to that temperature.

[0063] Figure 7 is a flowchart illustrating the method for manufacturing a sand mold according to Embodiment 6. The process in this flowchart is introduced in step S2 of Figure 1.

[0064] When molding begins, in step S60, the temperature of the self-hardening sand used for the sand mold is measured as the first temperature. Then, in step S61, the chemical mixture ratio is set to a ratio corresponding to the standard hardening speed corresponding to the sand temperature. Subsequently, in step S62, the temperature of the metal frame is measured, and in step S63, the chemical mixture ratio is changed to reflect the temperature of the metal frame.

[0065] Next, in step S64, it is determined whether or not a chilling iron is used for the sand mold to be created.

[0066] If a chiller is used (YES in S64), the temperature of the chiller is measured in step S65, and the drug mixture ratio is changed in step S66 to reflect the chiller temperature, and the process proceeds to step S67. On the other hand, if a chiller is not used (NO in S64), steps S65 and S66 are not performed, and the process proceeds to step S67.

[0067] In step S67, it is determined whether the material of the base plate for the sand mold to be created is metal or not. If the surface plate is made of metal (YES in S67), in step S68 the temperature of the surface plate is measured, and in step S69 the chemical mixture ratio is changed to reflect the temperature of the surface plate, and the process proceeds to step S70. On the other hand, if the surface plate is not made of metal (NO in S67), steps S68 and S69 are not performed, and the process proceeds to step S70.

[0068] Step S70 determines whether the material of the sand mold to be created is metal or not. If the model material is metal (YES in S70), in step S71, the temperature of the model is measured, and in step S72, the drug mixture ratio is changed to reflect the model temperature, and the process proceeds to step S73. On the other hand, if the model material is not metal (NO in S70), steps S71 and S72 are not performed, and the process proceeds to step S73.

[0069] In step S73, molding is performed using sand with the chemical mixture ratio determined by the processes in S61 to S72.

[0070] By using the above casting method, Embodiment 6 can more accurately reflect the influence that chills, metal models, metal base plates, and metal frames, which have a large heat capacity, have on the temperature of the casting sand.

[0071] Here, the temperatures of the sand, metal frame, chill, surface plate, and model measured in steps S60, S62, S65, S68, and S71, respectively, may be measured by an operator or an automatic acquisition mechanism may be provided. Furthermore, the temperatures of the sand, metal frame, chill, metal model, and metal surface plate after being left for a long time after use can be considered to be approximately the same as the ambient temperature. Therefore, the ambient temperature may be measured and the measured ambient temperature may be used as a substitute for the temperatures of the sand, metal frame, chill, metal model, and metal surface plate.

[0072] Regarding the chemical formulation information, the mixing ratios of the hardener, binder, and diluent to the sand may be directly specified to the controller, or information to correct the hardening speed may be input to the controller. Alternatively, the temperature of the sand around the model may be predicted, and information to correct the temperature of the sand used for adjusting the hardener formulation may be sent to the controller.

[0073] Embodiment 7. Embodiment 7 describes an example of reducing the burden on workers in Embodiment 1 by introducing a sand mold manufacturing support system.

[0074] Figure 8 is a diagram illustrating the sand mold manufacturing support system according to Embodiment 7.

[0075] First, in process S81, the model 12, the chill plate 13, and the metal frame 11 are placed on the surface plate 10.

[0076] Figure 9 shows the basic configuration of the manufacturing support system 50 and the drug formulation controller 20. The controller 20 includes a CPU (Central Processing Unit) 20A, memory 20B, and a communication interface 20C. The manufacturing support system 50 includes a CPU 50A, memory 50B, and a communication interface 50C.

[0077] CPUs 20A and 50A operate as the formulation determination processing unit of the controller 20 and the correction information generation unit of the manufacturing support system 50, respectively, by executing various programs. Each CPU has the function of performing various processes by executing a program, but some or all of these functions may be implemented using dedicated hardware circuits such as ASICs (Application Specific Integrated Circuits) or FPGAs (Field-Programmable Gate Arrays).

[0078] Furthermore, memory 20B and 50B provide storage areas for program code and various variables when the CPU executes various programs. Examples of memory include volatile memory such as DRAM (dynamic random access memory) and SRAM (static random access memory), or non-volatile memory such as ROM (read-only memory) and flash memory.

[0079] The communication interfaces 20C and 50C are the parts that exchange information between devices, and may be either wired or wireless.

[0080] Returning to Figure 8, in process S82, the CPU 50A of the manufacturing support system 50 acquires information on the presence or absence of a chiller 13 for the product to be manufactured on the molding line. Here, the information on whether or not the chiller is used may be entered by the operator, or a mechanism may be provided to acquire it automatically.

[0081] The CPU 50A of the manufacturing support system 50 then transmits curing speed correction information to the chemical formulation controller 20, depending on whether or not a chiller is used. The information transmitted to the controller 20 may directly specify the mixing ratios of the hardener, binder, and diluent, or it may transmit information to correct the curing speed in the same way as manual correction. Alternatively, if the formulation is adjusted based on the sand temperature, the CPU 50A may predict the temperature of the sand around the chiller and transmit information to correct the temperature of the sand used for adjusting the hardener formulation.

[0082] Next, in step S84, the controller 20 controls the binder supply unit 21, the hardener supply unit 22, and the diluent supply unit 23 based on the curing rate correction information transmitted from the manufacturing support system 50 to determine the amount of binder, hardener, and diluent to be added. Then, the binder, hardener, and diluent are mixed in the mixer 24 and poured into the metal frame 11, while the worker compacts it with their hands and feet to manufacture the sand mold. The subsequent steps are the same as steps S3 to S9 in Figure 1, so the explanation will not be repeated.

[0083] In Embodiment 7, by using the manufacturing support system 50, the hardening speed of the sand mold can be kept constant even when using a chilling iron, and the burden on the worker can be reduced.

[0084] Embodiment 8. Embodiment 8 describes an example of reducing the burden on workers in Embodiment 2 by introducing a sand mold manufacturing support system.

[0085] Figure 10 is a diagram illustrating the sand mold manufacturing support system according to Embodiment 8.

[0086] First, in step S91, the model 12, the preheated chill plate 13, and the metal frame 11 are placed on the surface plate 10.

[0087] Next, in process S92, the manufacturing support system 50 acquires information regarding the material of the model to be manufactured and the base plate. Here, the information regarding the material of the model may be entered by the operator, or a mechanism may be provided to acquire it automatically.

[0088] In process S93, the manufacturing support system 50 transmits curing rate correction information corresponding to the materials of the model and surface plate to the chemical compounding controller 20. The information transmitted to the controller 20 may directly specify the mixing ratios of the hardener, binder, and diluent, or it may transmit information to correct the curing rate in the same way as manual correction. Alternatively, if the compounding is adjusted based on the temperature of the sand, the system may predict the temperature of the sand around the model and transmit information to correct the temperature of the sand used for adjusting the hardener compounding.

[0089] Then, in step S94, the controller 20 controls the binder supply unit 21, the hardener supply unit 22, and the diluent supply unit 23 based on the curing rate correction information transmitted from the manufacturing support system 50 to determine the amount of binder, hardener, and diluent to be added. The binder, hardener, and diluent are then mixed in the mixer 24 and poured into the metal frame 11, while the worker compacts it with their hands and feet to manufacture the sand mold. The subsequent steps are the same as steps S3 to S9 in Figure 1, so the explanation will not be repeated.

[0090] By using the manufacturing support system of Embodiment 8, the hardening speed of the sand mold can be kept constant even when using multiple different types of models or surface plates, and the burden on the worker can be reduced.

[0091] Embodiment 9. Embodiment 9 is characterized in that the sand mold manufacturing support system described in Embodiment 7 has a mechanism that automatically determines the presence or absence of a chilling plate by image recognition.

[0092] Figure 11 is a diagram illustrating the sand mold manufacturing support system according to Embodiment 9. First, in process S101, the model 12, chill plate 13, and mold frame 11 are placed on the base plate 10.

[0093] Next, in step 102, the surface plate 10 is photographed by the camera 51, and the image is transmitted to the manufacturing support system 50. In step S103, the manufacturing support system 50 determines the presence or absence of the chill plate 13 by image recognition.

[0094] Here, the logic for detecting chills using image recognition is not limited. For example, the shape of the chills could be registered in advance, and the chills could be recognized by shape recognition. Alternatively, since mold release agents are usually applied to the surface plate and model, but not to the chills, chills could be detected based on differences in color or reflectivity.

[0095] Then, in process S104, the manufacturing support system 50 transmits curing speed correction information, depending on whether or not a chiller is used, to the chemical compounding controller 20.

[0096] In the subsequent step S105, the controller 20 controls the binder supply unit 21, the hardener supply unit 22, and the diluent supply unit 23 based on the curing rate correction information transmitted from the manufacturing support system 50 to determine the amount of binder, hardener, and diluent to be added. Then, the binder, hardener, and diluent are mixed in the mixer 24 and poured into the metal frame 11, while the worker compacts it by stepping on it with their hands and feet to manufacture the sand mold. The subsequent steps are the same as steps S3 to S9 in Figure 1, so the explanation will not be repeated.

[0097] According to the manufacturing support system 50 of Embodiment 9, even without operator input, information for correcting the curing speed can be automatically sent to the controller 20, enabling uniform curing of the sand mold.

[0098] Embodiment 10. Embodiment 10 is characterized in that, in the sand mold manufacturing support system described in Embodiment 7 or Embodiment 8, it has a mechanism that automatically determines the presence or absence of a chill plate and the material of the model using an RFID (Radio Frequency Identification) tag embedded in the model or surface plate. RFID tags can read information using radio waves. As long as the radio waves can reach the tag, the information can be read even if the tag is far away.

[0099] Figure 12 is a diagram illustrating the sand mold manufacturing support system according to Embodiment 10.

[0100] First, in process S111, the model 12, the chill plate 13, and the metal frame 11 are placed on the surface plate 10.

[0101] Next, in process S112, the RFID reader 53 reads information about the model to be fabricated and the material of the surface plate from the RDIF tag 54 attached to the surface plate 10, and transmits it to the database 52.

[0102] When using a handheld RFID reader, the RFID tag 54 can be attached to either the mounting plate used to fix the model or to the model itself. Furthermore, when a fixed RFID reader 53 is permanently installed to automatically acquire RFID tag information on the molding line, it is preferable to attach the RFID tag 54 to the side of the mounting plate 10, as shown in Figure 12.

[0103] In process S113, the database 52 identifies information from the received information regarding the presence or absence of a chiller 13 for the relevant product, the material of the model 12, and the material of the surface plate 10, and transmits this information to the manufacturing support system 50.

[0104] The method for determining the presence or absence of the cooler 13 and the material of the model 12 from the information of the read RFID tag 54 is not limited. For example, information regarding the presence or absence of the cooler and the material of the model may be entered into the RFID tag 54. Alternatively, only the model number of the manufacturing unit may be recorded in the RFID tag 54, and a database 52 may be prepared that records the model number of the manufacturing unit, the presence or absence of the cooler, and the material of the model, etc. The model number recorded in the read RFID tag 54 may be compared with the information in the database 52 to determine the presence or absence of the cooler and the material of the model, etc.

[0105] In process S114, the manufacturing support system 50 transmits information to the chemical compounding controller 20 regarding the presence or absence of the chilling plate 13 and the curing speed correction information according to the materials of the model and surface plate. The information transmitted to the controller 20 may directly specify the mixing ratios of the hardener, binder, and diluent, or it may transmit information to correct the curing speed in the same way as manual correction. Alternatively, if the compounding is adjusted based on the temperature of the sand, the system may predict the temperature of the sand around the model and transmit information to correct the temperature of the sand used for adjusting the hardener compounding.

[0106] Then, in step S115, the controller 20 controls the binder supply unit 21, the hardener supply unit 22, and the diluent supply unit 23 based on the hardening rate correction information transmitted from the manufacturing support system 50 to determine the amount of binder, hardener, and diluent to be added. The binder, hardener, and diluent are then mixed in the mixer 24 and poured into the metal frame 11, while the worker compacts it with their hands and feet to manufacture the sand mold. The subsequent steps are the same as steps S3 to S9 in Figure 1, so the explanation will not be repeated.

[0107] The manufacturing support system of Embodiment 10 can automatically transmit curing speed correction information even without operator input.

[0108] Embodiment 11. Embodiment 11 is a sand mold manufacturing support system characterized by measuring the temperature of at least one of the chill plate, surface plate, model, and mold frame, and correcting the hardener formulation according to that temperature.

[0109] Figure 13 is a diagram illustrating the sand mold manufacturing support system according to Embodiment 11.

[0110] First, in process S121, the model 12, the chill plate 13, and the metal frame 11 are placed on the surface plate 10.

[0111] Next, in process S122, the manufacturing support system 50 obtains the temperature of at least one of the chiller, surface plate, model, and metal frame.

[0112] Here, the temperatures of the chill plates, surface plates, models, and metal frames may be measured by the worker and entered into the manufacturing support system 50, or a mechanism may be provided for the manufacturing support system 50 to automatically acquire these temperatures. Furthermore, since the temperatures of chill plates, surface plates, models, and metal frames left for a long period of time after use can be considered to be approximately the same as the ambient temperature, the ambient temperature may be used as a substitute for the temperatures of chill plates, surface plates, models, and metal frames.

[0113] In the subsequent step S123, the manufacturing support system 50 transmits curing rate correction information corresponding to the temperature of the chiller 13, the temperature of the model 12, and the temperature of the surface plate to the chemical compounding controller 20. The information transmitted to the controller 20 may directly specify the mixing ratios of the hardener, binder, and diluent, or it may transmit information to correct the curing rate in the same way as manual correction. Alternatively, if the compounding is adjusted based on the temperature of the sand, the system may predict the temperature of the sand around the model and transmit information to correct the temperature of the sand used for adjusting the hardener compounding.

[0114] Then, in step S124, the controller 20 controls the binder supply unit 21, the hardener supply unit 22, and the diluent supply unit 23 based on the hardening rate correction information transmitted from the manufacturing support system 50 to determine the amount of binder, hardener, and diluent to be added. The binder, hardener, and diluent are then mixed in the mixer 24 and poured into the metal frame 11, while the worker compacts it by stepping on it with their hands and feet to manufacture the sand mold. The subsequent steps are the same as steps S3 to S9 in Figure 1, so the explanation will not be repeated.

[0115] By using the manufacturing support system 50 shown in Embodiment 11, the influence of chills, surface plates, models, and metal frames with high heat capacity on the temperature of the casting sand can be more accurately reflected in the mixing ratio of binders, hardeners, and diluents.

[0116] Embodiment 12. Embodiment 12 is a sand mold manufacturing support system characterized by measuring the temperature of at least one of the chill, surface plate, model, and mold frame, taking into consideration whether or not a chill is used, the material of the surface plate, and the material of the model, and correcting the hardener mixture according to that temperature.

[0117] Figure 14 is a diagram illustrating the sand mold manufacturing support system according to Embodiment 12.

[0118] First, in process S121, the model 12, the chill plate 13, and the metal frame 11 are placed on the surface plate 10.

[0119] Next, in process S122A, the manufacturing support system 50 acquires information regarding the presence or absence of a chiller 13 for the product to be manufactured on the molding line. Here, the information regarding the use of the chiller may be entered by the operator, or a mechanism for automatically acquiring this information may be provided. Then, in process S122B, the manufacturing support system 50 acquires information regarding the materials of the model and the base plate to be manufactured. Here, the information regarding the material of the model may be entered by the operator, or a mechanism for automatically acquiring this information may be provided. Next, in process S122C, the manufacturing support system 50 acquires the temperature of at least one of the chiller, base plate, model, and mold.

[0120] Here, the temperatures of the chill plates, base plates, models, and metal frames may be measured by the worker and entered into the manufacturing support system 50, or a mechanism may be provided for the manufacturing support system 50 to automatically acquire these temperatures. Furthermore, since the temperatures of chill plates, base plates, models, and metal frames left for a long time after use can be considered to be approximately the same as the ambient temperature, the ambient temperature may be measured and used as the temperature of the chill plates, base plates, models, and metal frames.

[0121] In the subsequent process S123, the manufacturing support system 50 takes into account whether a chiller is used, the material of the surface plate, and the material of the model, and transmits curing rate correction information corresponding to the temperature of the chiller 13, the temperature of the model 12, and the temperature of the surface plate to the chemical compound controller 20. If a chiller is used, the temperature of the chiller is measured, and the chemical compound ratio is changed to reflect the chiller temperature. On the other hand, if a chiller is not used, the chemical compound ratio is not changed. Also, if the material of the surface plate is metal, the temperature of the surface plate is measured, and the chemical compound ratio is changed to reflect the temperature of the surface plate, and the process proceeds. On the other hand, if the material of the surface plate is not metal, the chemical compound ratio is not changed. Also, if the material of the model is metal, the temperature of the model is measured, and the chemical compound ratio is changed to reflect the temperature of the model. On the other hand, if the material of the model is not metal, the chemical compound ratio is not changed.

[0122] The chemical mixture information transmitted to the controller 20 may be information that directly specifies the mixing ratio of hardener, binder, and diluent to the sand, or it may be information that corrects the hardening speed, similar to manual correction. Alternatively, if the mixture is adjusted based on the sand temperature, the controller may predict the temperature of the sand around the model and transmit information that corrects the temperature of the sand used for adjusting the hardener mixture.

[0123] Then, in step S124, the controller 20 controls the binder supply unit 21, the hardener supply unit 22, and the diluent supply unit 23 based on the hardening rate correction information transmitted from the manufacturing support system 50 to determine the amount of binder, hardener, and diluent to be added. The binder, hardener, and diluent are then mixed in the mixer 24 and poured into the metal frame 11, while the worker compacts it by stepping on it with their hands and feet to manufacture the sand mold. The subsequent steps are the same as steps S3 to S9 in Figure 1, so the explanation will not be repeated.

[0124] By using the manufacturing support system 50 shown in Embodiment 12, the influence of chills, surface plates, models, and molds with high heat capacity on the temperature of the casting sand can be more accurately reflected in the mixing ratio of binders, hardeners, and diluents.

[0125] Embodiment 13. Embodiment 13 is characterized in that, in the sand mold manufacturing support system described in Embodiment 11, the temperature of at least one of the chill plate, surface plate, model, and mold frame is acquired using a non-contact thermometer.

[0126] Figure 15 is a diagram illustrating the sand mold manufacturing support system according to Embodiment 13.

[0127] First, in step S131, the model 12, the chill plate 13, and the metal frame 11 are placed on the surface plate 10.

[0128] Next, in process S132, the manufacturing support system 50 obtains the temperature of at least one of the chiller, surface plate, model, and metal frame from a non-contact thermometer 55.

[0129] Here, the non-contact thermometer 55 may be a spot-type radiation thermometer, or a thermal imaging camera that measures temperature in two dimensions and acquires a thermal image may be used. Although the thermal imaging camera is more complex than the spot-type radiation thermometer, it can determine whether or not a chiller is present, eliminating the need for a mechanism to determine the presence or absence of a chiller, thus simplifying the overall system.

[0130] In the subsequent step S133, the manufacturing support system 50 transmits curing rate correction information corresponding to the temperature of the chiller 13, the temperature of the model 12, and the temperature of the surface plate to the chemical compounding controller 20. The information transmitted to the controller 20 may directly specify the mixing ratios of the hardener, binder, and diluent, or it may transmit information to correct the curing rate in the same way as manual correction. Alternatively, if the compounding is adjusted based on the temperature of the sand, the system may predict the temperature of the sand around the model and transmit information to correct the temperature of the sand used for adjusting the hardener compounding.

[0131] Then, in step S134, the controller 20 controls the binder supply unit 21, the hardener supply unit 22, and the diluent supply unit 23 based on the hardening rate correction information transmitted from the manufacturing support system 50 to determine the amount of binder, hardener, and diluent to be added. The binder, hardener, and diluent are then mixed in the mixer 24 and poured into the metal frame 11, while the worker compacts it by stepping on it with their hands and feet to manufacture the sand mold. The subsequent steps are the same as steps S3 to S9 in Figure 1, so the explanation will not be repeated.

[0132] By using the manufacturing support system of Embodiment 13, curing speed correction information that accurately reflects the temperature of the model, etc., can be automatically transmitted even without input information from the operator.

[0133] Embodiment 14. Embodiment 14 is characterized by automatically suggesting at least one of the following blending amounts of hardener, binder, and diluent that has the lowest probability of producing defective products, based on past records of defective products and the conditions when manufacturing a new sand mold.

[0134] Referring to Figure 16, the sand mold manufacturing support system according to Embodiment 14 will be described. Embodiment 14 has a database 52 that stores records of past product defects, and the database 52 records the conditions under which the sand mold for casting the product was manufactured. The conditions under which the sand mold was manufactured include information on at least one of the following: whether or not a chill iron 13 was used, the material of the model 12, the material of the base plate 10, the temperature of the chill iron 13, the temperature of the model 12, the temperature of the base plate 10, and the temperature of the metal frame 11, as well as information on at least one of the proportions of hardener, binder, and diluent used when manufacturing the sand mold, and information on the temperature of the sand used.

[0135] First, in step S141, the model 12, the chill plate 13, and the metal frame 11 are placed on the surface plate 10.

[0136] Next, in process S142, the manufacturing support system 50 acquires information about the product for which a sand mold is to be newly manufactured. The product information acquired here includes at least one of the following: whether or not a chill is used, the temperature of the chill, and the material and temperature of the base plate and model.

[0137] Next, in step 143, the manufacturing support system 50 compares the acquired product information with the records of past product defects stored in the database 52 and determines the conditions for reducing the defect rate.

[0138] In the subsequent step S143, the manufacturing support system 50 transmits curing rate correction information corresponding to the determined conditions to the chemical compounding controller 20. The information transmitted to the controller 20 may directly specify the mixing ratios of the hardener, binder, and diluent, or it may transmit information to correct the curing rate in the same way as manual correction. Alternatively, if the compounding is being adjusted based on the temperature of the sand, the system may predict the temperature of the sand around the model and transmit information to correct the temperature of the sand used for adjusting the hardener compounding.

[0139] Then, in step S145, the controller 20 controls the binder supply unit 21, the hardener supply unit 22, and the diluent supply unit 23 based on the hardening rate correction information transmitted from the manufacturing support system 50 to determine the amount of binder, hardener, and diluent to be added. The binder, hardener, and diluent are then mixed in the mixer 24 and poured into the metal frame 11, while the worker compacts it by stepping on it with their hands and feet to manufacture the sand mold. The subsequent steps are the same as steps S3 to S9 in Figure 1, so the explanation will not be repeated.

[0140] By using the manufacturing support system of Embodiment 14, the drug formulation that results in the lowest defect rate can be automatically calculated based on past performance. The method used for this calculation may be linear regression to determine the relationship between past manufacturing conditions and the defect rate, or a nonlinear regression method may be used.

[0141] Embodiment 15. A sand mold manufacturing support system according to Embodiment 15 will now be described. In Embodiment 13, a model is generated by a learning device, and the generated model is used by an inference device. The inference results of the inference device are used in the manufacturing support system 50 shown in Figure 16.

[0142] The learning device and inference device are used to learn the relationship between the record of defects in cast products and the conditions under which the sand molds used to cast those products were manufactured. The learning device and inference device are connected to the manufacturing support system 50 via a network and may be separate devices from the manufacturing support system 50. Alternatively, the learning device and inference device may be built into the manufacturing support system 50. Furthermore, the learning device and inference device may reside on a cloud server.

[0143] <Learning Phase> Figure 17 is a diagram showing the configuration of the learning device of the manufacturing support system. The learning device 60 shown in Figure 17 comprises a data acquisition unit 61 and a model generation unit 62.

[0144] The data acquisition unit 61 acquires records of past defective castings and the conditions under which the sand mold for casting the product was manufactured as training data. The conditions under which the sand mold was manufactured include information on whether or not a chill was used, information on the material of the model, the material of the base plate, the temperature of the chill, the temperature of the model, the temperature of the base plate, and the temperature of the mold frame, as well as information on at least one of the proportions of hardener, binder, and diluent used when manufacturing the sand mold, and information on the temperature of the sand used.

[0145] The model generation unit 62 learns the probability of defects based on training data created from a combination of past defect records of cast products output from the data acquisition unit 61 and the conditions under which the sand mold for casting the product was manufactured. In other words, it generates a trained model that infers the chemical compounding ratio that results in the lowest defect rate from past defect records of products and the conditions under which the sand mold for casting the product was manufactured.

[0146] The model generation unit 62 can use any known learning algorithm, such as supervised learning, unsupervised learning, or reinforcement learning. As an example, the case where a neural network is applied will be described.

[0147] The model generation unit 62 learns the probability of defects occurring, for example, by supervised learning according to a neural network model. Here, supervised learning is a method in which a learning device is given pairs of input and result (label) data, learns features in that training data, and infers the result from the input.

[0148] Figure 18 shows an example of a neural network. A neural network consists of an input layer (X1-X3) made up of multiple neurons, a hidden layer (Y1-Y2) made up of multiple neurons, and an output layer (Z1-Z3) made up of multiple neurons. In Figure 18, there is one hidden layer, but there can be two or more. For example, in a three-layer neural network as shown in Figure 18, when multiple inputs are input to the input layer (X1-X3), these values ​​are multiplied by weights W1 (w11-w16) and input to the hidden layer (Y1-Y2), and the result is further multiplied by weights W2 (w21-w26) and output from the output layer (Z1-Z3). This output result changes depending on the values ​​of weights W1 and W2.

[0149] In Embodiment 15, the neural network learns the probability of defects occurring through so-called supervised learning, based on the record of past defective cast products acquired by the data acquisition unit 61 and training data created based on the conditions when the sand mold for casting the product was manufactured.

[0150] In other words, the neural network learns by inputting the conditions under which the sand mold was manufactured into the input layer and adjusting the weights W1 and W2 so that the output from the output layer approaches the record of defective products cast using that sand mold.

[0151] The model generation unit 62 generates and outputs a trained model by performing the training described above.

[0152] The trained model storage unit 63 stores the trained model output from the model generation unit 62.

[0153] Next, we will explain the learning process performed by the learning device 60 using Figure 19. Figure 19 is a flowchart of the learning process of the learning device.

[0154] First, in step S151, the data acquisition unit 61 acquires the record of defective cast products and the conditions under which the sand mold for casting the product was manufactured. Although the record of defective cast products and the conditions under which the sand mold was manufactured are acquired simultaneously, this is not limited to simultaneous acquisition. It is sufficient if the record of defective cast products and the conditions under which the sand mold was manufactured can be input in association with each other, and the data on the record of defective cast products and the conditions under which the manufactured sand mold was manufactured may be acquired at different times.

[0155] In step S152, the model generation unit 62 learns the probability of defects occurring in casting products through so-called supervised learning, based on training data created from a combination of the records of defective casting products acquired by the data acquisition unit 61 and the conditions when the sand mold was manufactured, and generates a trained model.

[0156] In step S153, the trained model storage unit 63 stores the trained model generated by the model generation unit 62.

[0157] <Utilization Phase> Figure 20 is a diagram showing the configuration of an inference device related to a manufacturing support system. The inference device 65 shown in Figure 20 comprises a data acquisition unit 66 and an inference unit 67.

[0158] The data acquisition unit 66 acquires the conditions under which the sand mold was manufactured. The inference unit 67 uses the trained model read from the trained model storage unit 63 to infer the defect rate during the manufacturing of the cast product. That is, by inputting the conditions under which the sand mold was manufactured, acquired by the data acquisition unit 66, into this trained model, the defect rate is inferred, and further, the chemical formulation that results in the lowest defect rate can be inferred and output to the controller 20.

[0159] In Embodiment 15, the system was described as using a trained model acquired by the model generation unit 62 of the manufacturing support system to output the drug formulation that results in the lowest defect rate. However, the inference unit 67 may acquire a trained model from outside the manufacturing support system and output the drug formulation that results in the lowest defect rate based on this trained model.

[0160] Figure 21 is a flowchart illustrating the process of obtaining the drug formulation with the lowest defect rate using an inference device.

[0161] First, in step S161, the data acquisition unit 66 acquires the conditions under which the sand mold was manufactured.

[0162] In step S162, the inference unit 67 inputs the conditions for manufacturing the sand mold into the trained model stored in the trained model memory unit 63, and obtains the drug formulation that results in the lowest defect rate.

[0163] In step S163, the inference unit 67 outputs the chemical formulation that results in the lowest defect rate obtained by the trained model from the casting product manufacturing support system to the chemical formulation controller 20.

[0164] In step S164, the chemical compound controller 20 controls the chemical compound based on the chemical compound that results in the lowest defect rate, as output from the inference unit 67. This reduces the defect rate of the cast products.

[0165] In this embodiment, we have described the case where supervised learning is applied to the learning algorithm used by the model generation unit 62, but this is not the only possible case. In addition to supervised learning, reinforcement learning, unsupervised learning, or semi-supervised learning can also be applied to the learning algorithm.

[0166] Furthermore, the learning algorithm used in the model generation unit 62 can be deep learning, which learns to extract the features themselves, or machine learning can be performed according to other known methods, such as genetic programming, functional logic programming, or support vector machines.

[0167] According to the manufacturing support system of Embodiment 15, the drug formulation with the lowest probability of producing defective products can be automatically suggested based on past manufacturing results.

[0168] [summary] Let us refer again to the drawings to summarize this disclosure.

[0169] (1) This disclosure relates to a method for manufacturing a sand mold for casting using self-hardening sand. As shown in Figure 2 or Figure 3, the method for manufacturing a sand mold comprises steps S22, S32, S34 to confirm whether or not a chill is used for the sand mold, the material of the model used for manufacturing the sand mold, and the material of the base plate, and steps S23, S33, S35 to determine the mixing ratio of a hardener, binder, and diluent to the self-hardening sand so as to change the mixing ratio of at least one of the hardener, binder, and diluent mixed into the self-hardening sand based on the information of whether or not a chill is used, the material of the model, and the material of the base plate that has been confirmed.

[0170] The above process can improve the quality of sand molds by suppressing variations in the hardening speed of sand molds caused by factors such as the use of chilling plates, the material of the model, or the material of the surface plate.

[0171] (2) A method for manufacturing a sand mold for casting using self-hardening sand, as shown in other aspects of the present disclosure, comprises a step S41 of preheating a chill 13 and a step S42 of embedding the preheated chill in self-hardening sand to form a sand mold.

[0172] By reducing temperature variations within the sand mold through the above process, variations in curing speed can be reduced, thereby improving the quality of the sand mold.

[0173] (3) In the method for manufacturing a sand mold as described in paragraph 2, as shown in Figure 5, the step of preheating the chill includes a step S51 in which the temperature of the self-hardening sand used for the sand mold is measured as the first temperature, a step S52 in which the temperature of the chill 13 used for the sand mold is measured as the second temperature, and a step S53 in which the difference between the first temperature and the second temperature is calculated, and the chill is not heated if the difference is less than the judgment value, and the chill is heated if the difference is equal to or greater than the judgment value.

[0174] By following the above process, the temperature of the sand mold can be made uniform, thereby equalizing the hardening speed and improving the quality of the sand mold.

[0175] (4) A method for manufacturing a casting sand mold using self-hardening sand, as shown in Figure 7, comprises: step S60 of measuring the temperature of the self-hardening sand used for the sand mold as a first temperature; steps S62, S65, S68, S71 of measuring the temperature of at least one of the chill, base plate, model, and frame used for the sand mold as a second temperature; and steps S63, S66, S69, S72 of calculating the temperature difference between the first temperature and the second temperature and determining the mixing ratio of at least one of the hardener, binder, and diluent to be mixed into the self-hardening sand.

[0176] The above process suppresses fluctuations in the hardening speed of the sand mold caused by the temperature of the metal frame, chill, model, or surface plate, thereby improving the quality of the sand mold.

[0177] (5) A method for manufacturing a sand mold as described in paragraph 1 or 2, comprising the steps of: measuring the temperature of the self-hardening sand used for the sand mold as a first temperature; measuring the temperature of at least one of the chill, surface plate, model, or metal frame used for the sand mold as a second temperature; and calculating the temperature difference between the first temperature and the second temperature, and determining the mixing ratio of at least one of the hardening agent, binder, and diluent to be mixed with the self-hardening sand.

[0178] (6) In other aspects, this disclosure relates to a method for manufacturing a cast product. As shown in Figure 1, the method for manufacturing a cast product comprises a step S5 of pouring molten metal into a sand mold (30, 31) manufactured by the method described in any one of paragraphs 1 to 3 and casting, and a step S6 of dismantling the sand mold after pouring.

[0179] Through the above process, it is possible to obtain cast products with improved quality. (7) In other aspects, the present disclosure relates to a manufacturing support system 50 for a sand mold for casting using self-hardening sand. As shown in Figures 8 and 9, the manufacturing support system 50 includes a formulation determination processing unit (50A) that determines the proportions of a hardener, binder, and diluent to be mixed into the self-hardening sand. The formulation determination processing unit (50A) is configured to acquire information on whether or not a chill is used for the sand mold, the material of the model used to manufacture the sand mold, and the material of the surface plate (S82), and to change the proportion of at least one of the hardener, binder, and diluent to be mixed into the self-hardening sand (S83).

[0180] With the above configuration, the quality of the sand mold can be improved by consistently controlling the hardening speed of the sand mold, regardless of whether a chill is used, the material of the model, or the material of the surface plate.

[0181] (8) The sand mold manufacturing support system described in paragraph 7 further includes an imaging unit (camera 51) that acquires an image of the model to be molded, as shown in Figure 11. The mixture determination processing unit (50A) is configured to determine the presence or absence of chill plates 13 from the image of the model by image analysis.

[0182] With the above configuration, the presence or absence of a chiller can be automatically determined regardless of the operator.

[0183] (9) The sand mold manufacturing support system 50 described in paragraph 7 further includes an information acquisition unit (RFID reader 53) that acquires information from a tag 54 on which information is recorded and which is installed on the model 12 to be molded or on the base plate 10 on which the model 12 is placed, as shown in Figure 12.

[0184] With the above configuration, information such as the presence or absence of a chilling plate, the material of the model, and the material of the surface plate can be automatically acquired regardless of the operator.

[0185] (10) A manufacturing support system 50 for casting using self-hardening sand, according to further aspects of the present disclosure, includes a formulation determination processing unit (50A) that determines the proportions of a hardener, binder, and diluent to be mixed into the self-hardening sand. As shown in Figures 13 and 9, the formulation determination processing unit (50A) is configured to measure the temperature of the self-hardening sand to be used for the sand mold as a first temperature, measure the temperature of at least one of the chill, base plate, model, and frame used for the sand mold as a second temperature (S122), calculate the temperature difference between the first temperature and the second temperature, and determine the proportion of at least one of the hardener, binder, and diluent to be mixed into the self-hardening sand based on the temperature difference (S123).

[0186] With the above configuration, the hardening speed of the sand mold can be kept constant regardless of the temperature of the mold frame, chill, model, or surface plate, thereby improving the quality of the sand mold.

[0187] (11) The sand mold manufacturing support system described in any one of paragraphs 7 to 9 includes a formulation determination processing unit that determines the proportions of a hardening agent, binder, and diluent to be mixed with self-hardening sand. The formulation determination processing unit is configured to measure the temperature of the self-hardening sand to be used as a first temperature, measure the temperature of at least one of the chill, surface plate, model, or metal frame used for the sand mold as a second temperature, calculate the temperature difference between the first temperature and the second temperature, and determine the proportion of at least one of the hardening agent, binder, and diluent to be mixed with the self-hardening sand based on the temperature difference.

[0188] (12) The sand mold manufacturing support system described in paragraph 11 further comprises a non-contact thermometer 55 that measures the temperature of at least one of the chill, base plate, model, or mold used in the sand mold as a second temperature, as shown in Figure 15.

[0189] With the above configuration, the temperature of the metal frame, chill, model, or surface plate can be automatically obtained regardless of the operator.

[0190] (13) The sand mold manufacturing support system described in paragraph 7 further comprises a database 52 that stores records of past defective product occurrences, as shown in Figure 16. The database 52 records manufacturing information indicating the manufacturing conditions of the defective product. The manufacturing information includes first information relating to at least one of the following when the suspected defective sand mold was manufactured: whether or not a chill was used, the temperature of the mold frame, the temperature of the chill, the temperature of the base plate, and the temperature of the model; second information relating to at least one of the amounts of hardener, binder, and diluent used when the suspected defective sand mold was manufactured; and third information indicating the temperature of the sand when the suspected defective sand mold was manufactured. The formulation determination processing unit (50A) is configured to obtain manufacturing information from the database 52 that shows the manufacturing conditions of past defective products (S143), and to automatically determine at least one of the hardener amount, binder amount, or diluent amount that is estimated to have the lowest probability of producing defective products (S144) from the manufacturing information and information corresponding to the manufacturing information of the newly targeted cast product for sand casting (S142).

[0191] With the above configuration, it is possible to automatically suggest the drug formulation with the lowest probability of producing defective products based on past performance.

[0192] (14) In the sand mold manufacturing support system described in paragraph 13, the formulation determination processing unit (50A) is configured to acquire training data including first information, second information, and third information from the database 52 as shown in Figures 16 to 19 (S151), and to use the training data to generate a trained model for inferring at least one of the hardener amount, binder amount, and diluent amount that has the lowest probability of producing defective products for a newly cast product to be sand molded (S152).

[0193] With the above configuration, it is possible to automatically suggest the drug formulation with the lowest probability of producing defective products based on past performance.

[0194] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the description of the embodiments above, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0195] 10 Surface plate, 11 Metal frame, 12 Model, 13 Chill plate, 20 Controller, 20B, 50B Memory, 20C, 50C Communication interface, 21 Binding agent supply unit, 22 Hardener supply unit, 23 Diluent supply unit, 24 Mixer, 25 Sand temperature sensor, 26 Display unit, 30 Upper mold, 31 Lower mold, 40 Cast product, 50 Manufacturing support system, 51 Camera, 52 Database, 53 RFID reader, 54 RFID tag, 55 Thermometer, 60 Learning device, 61, 66 Data acquisition unit, 62 Model generation unit, 63 Learned model storage unit, 65 Inference device, 67 Inference unit.

Claims

1. A method for manufacturing a sand mold for casting using self-hardening sand, A step of confirming whether or not a chilling iron is used for the sand mold, the material of the model used in the manufacture of the sand mold, and the material of the surface plate, A method for manufacturing a sand mold, comprising the step of determining the mixing ratio of the hardener, binder, and diluent to the self-hardening sand, such that the mixing ratio of at least one of the hardener, binder, and diluent mixed into the self-hardening sand is changed based on at least one piece of information, such as whether or not the chilling plate is used, the material of the model that has been checked, and the material of the surface plate.

2. A method for manufacturing a sand mold for casting using self-hardening sand, The process of preheating the chiller, A method for manufacturing a sand mold, comprising the steps of embedding the preheated chill in the self-hardening sand to form the sand mold.

3. The process of preheating the chiller is as follows: A step of measuring the temperature of the self-hardening sand used in the sand mold as the first temperature, A step of measuring the temperature of the chill used in the sand mold as the second temperature, A method for manufacturing a sand mold according to claim 2, comprising the steps of: calculating the difference between the first temperature and the second temperature; not heating the chiller if the difference is less than a determination value; and heating the chiller if the difference is equal to or greater than a determination value.

4. A method for manufacturing a sand mold for casting using self-hardening sand, A step of measuring the temperature of the self-hardening sand used in the sand mold as the first temperature, The process involves measuring the temperature of at least one of the chill, surface plate, model, or metal frame used in the sand mold as the second temperature, A method for manufacturing a sand mold, comprising the steps of: calculating the temperature difference between the first temperature and the second temperature; and determining the mixing ratio of at least one of the hardening agent, binder, and diluent to be mixed into the self-hardening sand.

5. A step of measuring the temperature of the self-hardening sand used in the sand mold as the first temperature, The process involves measuring the temperature of at least one of the chill, surface plate, model, or metal frame used in the sand mold as the second temperature, A method for producing a sand mold according to claim 1 or 2, comprising the steps of calculating the temperature difference between the first temperature and the second temperature, and determining the mixing ratio of at least one of the hardening agent, binder, and diluent to be mixed into the self-hardening sand.

6. A step of pouring molten metal into the sand mold manufactured by the method described in any one of claims 1 to 3 and casting, A method for manufacturing a cast product, comprising the step of dismantling a sand mold after pouring molten metal.

7. A manufacturing support system for sand molds for casting using self-hardening sand, The system includes a formulation determination processing unit that determines the proportions of a hardening agent, binder, and diluent to be mixed into the self-hardening sand. A sand mold manufacturing support system comprising: a formulation determination processing unit which acquires information on whether or not a chilling plate is used for the sand mold, the material of the model used to manufacture the sand mold, and the material of the surface plate, and which changes the mixing ratio of at least one of the hardening agent, binder, and diluent mixed into the self-hardening sand based on the information.

8. It further includes an imaging unit that acquires an image of the model to be molded, The sand mold manufacturing support system according to claim 7, wherein the formulation determination processing unit is configured to determine the presence or absence of a chill from an image of the model by image analysis.

9. The sand mold manufacturing support system according to claim 7, further comprising an information acquisition unit that acquires the information from a tag on which the information is recorded and which is installed on a model to be molded or on a surface plate on which the model is placed.

10. A manufacturing support system for sand molds for casting using self-hardening sand, The system includes a formulation determination processing unit that determines the proportions of a hardening agent, binder, and diluent to be mixed into the self-hardening sand. A sand mold manufacturing support system comprising: a formulation determination processing unit which measures the temperature of the self-hardening sand used for the sand mold as a first temperature, measures the temperature of at least one of the chill, surface plate, model, and metal frame used for the sand mold as a second temperature, calculates the temperature difference between the first temperature and the second temperature, and determines the mixing ratio of at least one of the hardener, binder, and diluent to be mixed into the self-hardening sand based on the temperature difference.

11. The system includes a formulation determination processing unit that determines the proportions of a hardening agent, binder, and diluent to be mixed into the self-hardening sand. A sand mold manufacturing support system according to any one of claims 7 to 9, wherein the composition determination processing unit is configured to measure the temperature of the self-hardening sand used for the sand mold as a first temperature, measure the temperature of at least one of the chill, surface plate, model, and metal frame used for the sand mold as a second temperature, calculate the temperature difference between the first temperature and the second temperature, and determine the mixing ratio of at least one of the hardener, binder, and diluent to be mixed into the self-hardening sand based on the temperature difference.

12. The sand mold manufacturing support system according to claim 11, further comprising a non-contact thermometer for measuring the temperature of at least one of the chill, surface plate, model, and metal frame used in the sand mold as the second temperature.

13. Furthermore, we have a database that stores records of past product defects. The aforementioned database records manufacturing information indicating the manufacturing conditions of the defective product. The aforementioned manufacturing information is First information relating to at least one of the following when manufacturing the suspected defective sand mold used in the manufacture of the aforementioned defective product: whether or not a chill was used, the temperature of the mold frame, the temperature of the chill, the temperature of the surface plate, and the temperature of the model, Second information relating to at least one of the amounts of hardener, binder, and diluent used when manufacturing the suspected defective sand mold, This includes a third piece of information indicating the temperature of the sand used when the suspected defective sand mold was manufactured, The sand mold manufacturing support system according to claim 7, wherein the formulation determination processing unit is configured to acquire manufacturing information indicating the manufacturing conditions of past defective products from the database, and to automatically determine at least one of the amounts of hardener, binder, and diluent that is estimated to have the lowest probability of producing defective products, based on the manufacturing information and information corresponding to the manufacturing information regarding the newly targeted cast product for sand casting.

14. The sand mold manufacturing support system according to claim 13, wherein the formulation determination processing unit is configured to acquire training data including the first information, the second information, and the third information from the database, and to use the training data to generate a trained model for inferring at least one of the curing agent amount, binder amount, and diluent amount that results in the lowest probability of producing defective products for a newly cast product to be sand-cast.

Images