JP5578707B2 - Mold production equipment - Google Patents

Description

  The present invention relates to an apparatus for producing a mold used for casting.

  Currently used molds are generally hard molds such as ordinary sand molds, high pressure molds, high speed molds and other clay molds as binders, thermosetting molds, self-hardening molds, gas curing molds, precision casting molds, etc. They are classified into special molds that use adhesive binders and other molds. These molds have merits and demerits, but they often have a problem that it takes time to solidify or cure the binder and it is difficult to stably produce the mold in a short time.

  Therefore, the present applicant fills a mold with a coated sand prepared by mixing a binder with a refractory aggregate, blows steam into the mold, and heats the binder with steam to solidify. It proposes a method for producing a mold by curing.

  FIG. 6 shows an example of an apparatus for producing a mold using water vapor (see Patent Documents 1 and 2, etc.). As shown in FIG. 6A, the injection port 11 is provided on the upper surface of the mold 1 formed by providing the cavity 10 therein, and the exhaust port 13 closed by the net 12 is provided on the lower surface of the mold 1. It is. The coated sand 2 is stored in a storage tank 14, and an air supply pipe 16 with a cock 15 is connected to the storage tank 14. Then, after the nozzle port 17 at the lower end of the storage tank 14 is matched with the injection port 11 of the mold 1, the inside of the storage tank 14 is pressurized by opening the cock 15 and blowing air into the storage tank 14. The coated sand 2 is blown into the mold 1 by this air pressure as shown in FIG. 6B, and the coated sand 2 is filled into the cavity 10 of the mold 1. Since the exhaust port 13 is blocked by the net 12, the coated sand 2 does not leak from the exhaust port 13.

  After filling the mold 1 with the coated sand 2 in this way, the storage tank 14 is removed from the inlet 11 of the mold 1, and then the steam pipe 19 is connected to the inlet 11 as shown in FIG. . The steam pipe 19 is connected to a steam generator 3 formed with a boiler or the like. Then, the cock 18 provided in the steam pipe 19 is opened, and the steam sent from the steam generator 3 is blown into the cavity 10 of the mold 1 through the steam pipe 19. The water vapor passes between the particles of the coated sand 2 filled in the mold 1 to heat the coated sand 2 and is then discharged from the exhaust port 13. Since water vapor has high condensation latent heat, by blowing water vapor in this way, the latent heat is transmitted when the water vapor contacts the coated sand 2, and the entire coated sand 2 in the mold 1 can be instantaneously heated. The binder can be solidified or cured in a short time. Therefore, it is possible to stably mold a mold in a short time.

Japanese Patent No. 3563973 Japanese Patent No. 4181251

  When the mold is manufactured by blowing water vapor into the mold 1 filled with the coated sand 2 as described above, the manufacturing process is performed as shown in FIGS. 6 (a) and 6 (b). 14 is connected to the mold 1 and the coated sand 2 is supplied and filled in the mold 1, and the steam pipe 19 is connected to the mold 1 as shown in FIG. It consists of a process of blowing water vapor.

  Then, the steam is supplied from the steam generator 3 only in the step of connecting the steam pipe 19 to the mold 1 and blowing steam in FIG. 6 (c), and in FIGS. 6 (a) and 6 (b), In the process of supplying and filling the coated sand 2 from the storage tank 14 to the mold 1, it is not necessary to supply water vapor from the water vapor generator 3.

  However, the water vapor generator 3 is generally formed with a boiler, and the boiler mainly generates water vapor by heating water mainly using a burner as a heat source, and FIG. If there is a process in which it is not necessary to supply water vapor from the water vapor generating device 3 as in (b), the production of water vapor is wasted, which has a problem in efficiency.

In addition, when heating the coated sand 2 by blowing water vapor into the mold 1 as shown in FIG. 6C, at the initial stage of blowing water vapor into the mold 1, a part of the heat of the water vapor is taken away by the mold 1. The heating efficiency of the coated sand 2 by steam was lowered, and there was a limit in shortening the molding time of the mold.

  The present invention has been made in view of the above points, and can provide a mold manufacturing apparatus that can obtain a high effect of shortening the molding time of the mold and that has high use efficiency of the steam generated by the steam generator. It is intended to do.

The mold manufacturing apparatus according to the present invention includes a mold 1 for mold molding having a cavity 10 filled with a coated sand 2 prepared by mixing a binder with a refractory aggregate, and a cavity 10 of the mold 1. In a mold manufacturing apparatus comprising a steam generator 3 for generating steam for heating the coated sand 2 filled therein, a steam delivery path 30 for delivering the steam produced by the steam generator 3, and a steam delivery path 30, provided in a branch connection, and provided in the mold 1 for supplying water vapor into the cavity 10 after the coated sand 2 is filled in the cavity 10 of the mold 1, and allows the heating fluid to pass therethrough. mold and the heating flow channel 5, the mold heat flow of the mold 1 the tip portion with branches connected separately to the steam delivery line 30 and steam supply passage 4 for heating the mold 1 by 5 Connect provided and is characterized by comprising a heating fluid supply passage 6 to be sent to the mold heating channel 5 steam as heating fluid.

According to the present invention, since the water vapor supply passage 4 for supplying the water vapor delivered from the water vapor generating device 3 into the mold 1 is provided, by heating the coated sand 2 filled in the mold 1 with water vapor, The entire coated sand 2 in the mold 1 can be instantaneously heated with high condensation latent heat, and the mold can be stably formed in a short time. Further, the mold heating channel 5 in the mold 1 is provided, so comprises a heating fluid supply passage 6 to send the steam fed from the steam generator 3 to the mold heating channel 5 of the mold 1 as a heating fluid, steam The mold 1 can be preheated by using it, and when the steam is supplied into the mold 1 and the coated sand 2 is heated, the heat of the water vapor can be suppressed from being lost to the mold 1, and the heating by the steam is performed. The efficiency can be increased, and the effect of shortening the molding time of the mold can be highly obtained. Moreover, in steps other than the step of supplying the water vapor into the mold 1 and heating the coated sand 2, the water vapor can be used for preheating the mold 1, and the use efficiency of the water vapor generated by the water vapor generator 3 is improved. It will be expensive.

In the present invention, are those wherein the steam fed from the steam feeding path 30 is intended to be constantly supplied to the mold heating channel 5 through a heated fluid supply passage 6 and the mold heating channel 5 is provided with a water vapor return path 36 for returning the water vapor having passed through 5 to the water vapor generator 3.

  According to the present invention, the steam generated by the steam generator 3 can be used as it is for preheating the mold 1.

The mold manufacturing method according to the present invention includes a mold 1 for mold molding having a cavity 10 filled with a coated sand 2 prepared by mixing a refractory aggregate with a binder, and a cavity of the mold 1. In a mold manufacturing apparatus comprising a steam generator 3 for generating steam that heats the coated sand 2 filled in 10, a steam delivery path 30 for delivering steam produced by the steam generator 3, and steam delivery A branch connection to the passage 30 is provided, and a steam supply passage 4 for supplying water vapor into the cavity 10 after the coated sand 2 is filled in the cavity 10 of the mold 1 and the mold 1 are provided to pass the heating fluid. In this way, the mold heating flow path 5 for heating the mold 1, the heat exchanger 7, and the water vapor supply path 4 are branched and connected to the water vapor delivery path 30 and the heat exchanger 7. The steam supplied to the heat exchanger 7 through the heat exchange steam supply path 65 provided between the connected heat exchange steam supply path 65 and the heat exchanger 7 and the mold heating path 5 of the mold 1. And a heating fluid supply passage 6 for sending a heating medium heated by heat exchange to the mold heating passage 5 as a heating fluid .

  According to the present invention, the water vapor generated by the water vapor generator 3 can be used for preheating the mold 1 by exchanging heat with the heat medium.

  In the present invention, the steam generator 3 includes a superheater 8, and the steam is superheated steam generated by overheating in the superheater 8.

  Superheated steam is high-temperature dry steam, and by using such superheated steam as water vapor, the generation of condensed water from water vapor in the mold 1 is reduced, and the coated sand 2 in the mold 1 Heating efficiency can be increased.

The present invention also co over Ted sand 2 comprises a preheater 40 for preheating, the heating fluid to send the water vapor and heat exchange to the heated heating fluid delivered through the steam delivery path 30 from the steam generator 3 to the preheater 40 A supply path 48 is provided.

According to the present invention, the coated sand 2 can be preheated using water vapor, and the effect of shortening the molding time of the mold can be obtained by suppressing the water vapor from condensing in the mold 1. At the same time, the steam can be used for preheating the coated sand 2 in a process other than the process of supplying the steam into the mold 1 and heating the coated sand 2. Will be higher.

According to the present invention, since the steam supply path 4 for supplying the steam delivered from the steam generator 3 into the mold 1 is provided, by heating the coated sand 2 filled in the mold 1 with steam, The entire coated sand 2 in the mold 1 can be instantaneously heated with high condensation latent heat, and the mold can be stably formed in a short time. Further, a heating fluid is provided in the mold 1 and provided with a mold heating flow path 5, and the steam heated by the steam generator 3 or a heat medium exchanged with the steam is used as a heating fluid to the mold heating flow path 5 of the mold 1. Since the supply path 6 is provided, the mold 1 can be preheated using steam, and when the steam is supplied into the mold 1 and the coated sand 2 is heated, the heat of the steam is generated by the mold. 1 can be suppressed and the effect of shortening the molding time of the mold can be increased, and the steam is formed in a process other than the process of supplying the steam into the mold 1 and heating the coated sand 2. It can be used for preheating of the mold 1 and the use efficiency of the water vapor generated by the water vapor generator 3 is increased.

BRIEF DESCRIPTION OF THE DRAWINGS It shows an example of embodiment of this invention, (a) is a schematic diagram of a shaping | molding die, a water vapor generator, etc., (b) is a schematic diagram of a shaping die, (c) is another example of a shaping die. It is a schematic sectional drawing. It is the schematic of a storage tank, a steam generator, etc. which show an example of embodiment of this invention. It is the schematic of the storage tank which shows another example of embodiment of this invention. It is the schematic of a shaping | molding die, a water vapor generator, etc. which show an example of other embodiment of this invention. It is the schematic of a storage tank, a steam generator, etc. which show an example of other embodiment of this invention. A prior art example is shown, and (a) to (c) are schematic views.

  Embodiments of the present invention will be described below.

  FIG. 1 shows an example of an embodiment of the present invention. The molding die 1 is formed by providing a cavity 10 therein, and in the embodiment shown in FIG. An injection port 11 is provided on the upper surface of the mold 1, and an exhaust port 13 is provided on the lower surface of the mold 1 and is closed with a net 12 such as a wire net.

  A mold heating channel 5 is provided in the mold 1. In the embodiment of FIG. 1, the mold heating flow path 5 is formed by providing a hollow path in the wall surface of the mold 1. A pair of mold heating flow paths 5 are provided so that the mold 1 can be divided into left and right halves. The pair of mold heating flow paths 5 can surround the entire surface of the cavity 10 as shown in FIG. It is formed in a meandering shape. The mold heating flow path 5 is opened on the outer surface of the mold 1, with one end serving as an inlet 22 and the other end serving as an outlet 23.

  The mold heating channel 5 is formed in a meandering form as shown in FIGS. 1A and 1B, and as shown in FIG. 1C, a cavity 10 is enclosed in the wall surface of the mold 1. A cavity may be provided as described above, and the mold heating flow path 5 may be formed by this cavity. Furthermore, the mold heating channel 5 may be formed in the wall surface of the mold 1 as described above, or may be formed by wrapping a pipe around the outer surface of the mold 1.

  The steam generator 3 is formed with a boiler 25, and a water introduction path 27 provided with an on-off valve 26 is connected to the boiler 25. Water supplied from the water introduction path 27 can be heated in the boiler 25 to generate water vapor (saturated water vapor). In FIG. 1, 28 is a pressure gauge and 29 is a safety valve. When the steam generated in the boiler 25 is used as it is, it is sent out from the steam delivery path 30 connected to the boiler 25. Further, by connecting the superheater 8 to the water vapor delivery path 30, the water vapor generated by the boiler 25 can be further heated by the superheater 8 and sent out from the water vapor delivery path 30 as superheated steam. Superheated steam is water vapor in a complete gas state generated by further heating saturated steam and having a temperature equal to or higher than the boiling point, and is dry steam at 100 ° C. or higher. The superheated steam may be one that has been expanded at a constant pressure without increasing the pressure, or may be pressurized steam that has been increased in pressure without being expanded. Although the temperature of the superheated steam is not particularly limited, the temperature of the superheated steam can be increased to about 900 ° C., and therefore, the temperature may be set between 100 and 900 ° C. as necessary. In FIG. 1, 31 is an on-off valve provided on the entry side of the steam delivery path 30 to the superheater 8, and 32 is an on-off valve provided on the exit side of the steam delivery path 30 from the superheater 8.

  The steam supply path 4 and the heating fluid supply path 6 are branched and connected to the end of the steam delivery path 30 ahead of the on-off valve 32. The steam supply path 4 and the heating fluid supply path 6 are provided with on-off valves 33 and 34, respectively. The leading portion of the heating fluid supply path 6 branches according to the number of mold heating channels 5 provided in the mold 1 and is formed as heating fluid supply branches 6a and 6a. An open / close valve 35 is provided on each of 6a and 6a. The heating fluid supply path 6 is connected to the mold heating flow path 5 by coupling the leading end of the heating fluid supply branch path 6 a to the inlet 22 of the mold heating flow path 5 of the mold 1. One end of the water vapor return path 36 is connected to the outlet 23 of the mold heating flow path 5, and the other end of the water vapor return path 36 is connected in a branched state to the water introduction path 27.

  Although it does not specifically limit as coated sand in this invention, The thing which coat | covered the surface of the refractory aggregate with the binder by mixing a binder with a refractory aggregate can be used.

  The refractory aggregate is not particularly limited, and can be exemplified by dredged sand, mountain sand, alumina sand, olivine sand, chromite sand, zircon sand, mullite sand, and other artificial sand, These may be used alone or in combination of two or more.

  Further, as the binder, a thermosetting resin is generally used, but saccharides can also be used. You may make it use a thermosetting resin and saccharides together as a binder.

  Examples of the thermosetting resin used for the binder include phenol resins such as resol type, novolac type, and benzylic ether type, furan resin, isocyanate compound, amine polyol resin, polyether polyol resin, and the like. These can be combined with isocyanate compounds, organic esters, hexamethylenetetramine, etc. as curing agents, and tertiary amines, pyridine derivatives, organic sulfonic acids, etc. as curing catalysts, and can be used with thermosetting properties. It is. Among these, a phenol resin is preferable.

  In addition, as the saccharide used in the binder, monosaccharides, oligosaccharides, and polysaccharides can be used, and one type selected from various monosaccharides, oligosaccharides, and polysaccharides can be used alone. You can also select seeds and use them together.

  Although it does not specifically limit as monosaccharide, Glucose (glucose), fructose (fructose), galactose, etc. can be mentioned.

  Examples of oligosaccharides include disaccharides such as maltose (malt sugar), sucrose (sucrose), lactose (lactose), and cellobiose.

  Furthermore, as polysaccharides, there are starch sugar, dextrin, xanthan gum, curdlan, pullulan, cycloamylose, chitin, cellulose, starch, etc., and one of these can be selected or used in combination of two or more. it can. Examples of starch include raw starch and processed starch. Specifically, raw starch such as potato starch, corn starch, high amylose, sweet potato starch, tapioca starch, sago starch, rice starch, amaranth starch, and these modified starches (roasted dextrin, enzyme-modified dextrin, acid-treated starch, Oxidized starch, dialdehyde starch, etherified starch (carboxymethyl starch, hydroxyalkyl starch, cationic starch, methylolated starch, etc.), esterified starch (acetic acid starch, phosphate starch, succinate starch, octenyl succinic acid starch, maleic acid Starch, higher fatty acid esterified starch, etc.), cross-linked starch, kraft starch, wet heat-treated starch, etc. Among these, roasted dextrin, enzyme modified Dextrin, acid treatment starches, those low molecular weight as oxidized starch, and low viscosity, such as cross-linked starch starches are preferred.

  The binder may contain a carboxylic acid as a curing agent for saccharides, particularly polysaccharides. The carboxylic acid is not particularly limited, and examples thereof include oxalic acid, maleic acid, succinic acid, citric acid, butanetetradicarboxylic acid, methyl vinyl ether-maleic anhydride copolymer, and the like. The content of the carboxylic acid in the binder is preferably such that the amount of the carboxylic acid to the saccharide is 0.1 to 10 parts by mass of the carboxylic acid with respect to 100 parts by mass of the saccharide. Carboxylic acid is preferably mixed with saccharide in a state of being dissolved in water in advance because the effect as a curing agent is exhibited highly.

  Then, by adding a binder to the refractory aggregate particles and mixing them, the surface of the refractory aggregate can be coated with a coating layer containing the binder to obtain a coated sand. . The amount of the binder to be coated on the refractory aggregate differs depending on the components and applications and cannot be specified unconditionally. Is generally preferred. Examples of a method for coating the surface of the refractory aggregate with a binder include a hot coat method, a cold coat method, a semi-hot coat method, and a powder solvent method. In any method, a coated layer made of a solid binder at normal temperature (30 ° C.) can be coated on the surface of the refractory aggregate to obtain granular coated sand.

FIG. 2 shows a storage tank 14 for storing the coated sand 2, and a nozzle port 17 provided with a cock 39 is provided at the lower end of the storage tank 14. The storage tank 14 is provided with a preheater 40 for preheating the coated sand 2 stored in the storage tank 14. In the embodiment of FIG. 2, the preheater 40 is formed by a preheating pipe 40 a that is a heat exchange pipe bent in a spiral, and the preheating pipe 40 a is inserted into the central portion of the storage tank 14.

  As described above with reference to FIG. 1, the water vapor supply path 4 and the heating fluid supply path 6 are branched and connected to the water vapor delivery path 30 of the water vapor generating device 3. The path 41 is branched. The preheating water vapor supply path 41 is connected to a preheating heat exchanger 42. 52 is an on-off valve provided in the preheating steam supply passage 41. In the preheating heat exchanger 42, an introduction chamber 43 is formed at one end thereof, and a lead-out chamber 44 is formed at the other end, and the heat exchange chamber 45 is formed between the introduction chamber 43 and the lead-out chamber 44. It has become. A large number of heat exchange pipes 51 communicating with the introduction chamber 43 and the outlet chamber 44 are provided in the heat exchange chamber 45. The preheating steam supply path 41 is connected to the introduction chamber 43 of the preheating heat exchanger 42, and one end of the steam return path 46 is connected to the outlet chamber 44, and the other end of the steam return path 46 is connected. Is connected in a branched state to the water introduction path 27 of the boiler 25 in the same manner as the water vapor return path 36 of FIG. A fluid introduction path 47 is connected to one end of the heat exchange chamber 45 of the preheating heat exchanger 42, and a heating fluid supply path 48 is connected to the other end of the heat exchange chamber 45. In the embodiment of FIG. 2, a blower 49 such as a fan is provided in the fluid introduction path 47 so that air is sent to the heat exchange chamber 45 as a fluid. The other end of the heating fluid supply path 48 having one end connected to the heat exchange chamber 45 is connected to an inlet 50 at one end of a preheating pipe 40 a constituting the preheater 40.

  The apparatus shown in FIGS. 1 and 2 shares one water vapor generator 3. Water is supplied from the water introduction path 27 to the boiler 25 of the water vapor generating device 3, and water vapor is generated by the boiler 25. When the superheater 8 is provided in the steam generator 3, this steam can be further heated to generate superheated steam. The steam generated in this way is sent out from the steam delivery path 30 by opening the on-off valve 32.

Here, in FIG. 1, the on-off valve 33 of the steam supply path 4 is closed except when steam is supplied into the cavity 10 of the mold 1 and blown in, but the on-off valve 34 of the heating fluid supply path 6 is basically the same. Therefore, it is always open and is supplied through the heating fluid supply path 6 with the steam delivered from the steam delivery path 30 as a heating fluid. The water vapor that has passed through the heating fluid supply path 6 in this way is supplied from the inlet 22 to the mold heating flow path 5 of the mold 1 from the heating fluid supply branch path 6 a and passes through the mold heating flow path 5. It goes out to the steam return path 36 from the exit 23. Thus, when passing water vapor through the mold heating channel 5 of the mold 1, the mold 1 can be heated by the water vapor, and the temperature of the mold 1 can be prevented from being lowered. Is. The water vapor that has passed through the mold heating flow path 5 goes out to the water vapor return path 36, but since the heat is deprived in order to heat the mold 1, the temperature is lowered. Returned and regenerated to steam again.

  On the other hand, in FIG. 2, steam is always supplied from the steam delivery path 30 to the preheating steam supply path 41 that is branched and connected to the steam delivery path 30 of the steam generator 3. The steam that has passed through the preheating steam supply passage 41 enters the introduction chamber 43 of the preheating heat exchanger 42, passes through the heat exchange pipe 51, then moves to the outlet 44, and is then discharged to the steam return passage 46. . In addition, air is sent into the heat exchange chamber 45 by the blower 49, and when this air passes through the heat exchange chamber 45, heat exchange is performed with water vapor passing through the heat exchange pipe 51, and in the heat exchange chamber 45. Air is heated. The heated air is sent as a heating fluid from the heat exchange chamber 45 to the heating fluid supply path 48, and the heated air that has passed through the heating fluid supply path 48 enters the preheating pipe 40 a constituting the preheater 40 at one end 50. Supplied from The coated sand 2 is always stored in the storage tank 14, and the preheating pipe 40a disposed in the central portion of the storage tank 14 is in a state of being buried in the coated sand 2, so that the heated air is supplied to the preheating pipe. When passing through 40a, the coated sand 2 can be heated to preheat the coated sand 2. The heated air that has passed through the preheating pipe 40a is discharged into the atmosphere from the outlet 53 at the end. Further, since the temperature of the steam that has passed through the preheating heat exchanger 42 and is discharged to the steam return path 46 is lowered, it is returned from the water introduction path 27 to the boiler 25 and regenerated again as steam. Here, a large number of small holes may be provided in the preheating pipe 40a along the longitudinal direction thereof, and the heated air passing through the preheating pipe 40a may be blown out from the small holes. The air can be directly applied to the coated sand 2 to preheat the coated sand 2 more efficiently.

Next, a method for producing a mold using the above apparatus will be described. First, the nozzle port 17 of the storage tank 14 is connected to the injection port 11 of the mold 1. Then, the cock 39 of the nozzle port 17 is opened, the coated sand 2 stored in the storage tank 14 is supplied to the mold 1, and the cavity 10 is filled with the coated sand 2. Since the exhaust port 13 of the mold 1 is closed by the net 12, the coated sand 2 does not leak from the exhaust port 13. After the coated sand 2 is filled into the cavity 10 of the mold 1, the cock 39 of the storage tank 14 is closed, the connection of the storage tank 14 is disconnected from the inlet 11 of the mold 1, and the coated sand 2 is filled into the mold 1. The process ends.

  Next, the water vapor supply path 4 is connected to the inlet 11 of the mold 1. A connection nozzle 54 is provided at the tip of the water vapor supply path 4, and the water supply line 4 is connected to the injection port 11 by inserting the connection nozzle 54 into the injection port 11. When the on-off valve 33 is opened, the water vapor sent out from the water vapor delivery path 30 of the water vapor generator 3 is blown into the cavity 10 of the mold 1 through the water vapor supply path 4. When water vapor is blown into the mold 1, the water contacts the surface of the coated sand 2, so that the coated sand 2 can be directly heated by the high latent heat of the water vapor, and the temperature of the coated sand 2 is around 100 ° C. Rising rapidly. Moreover, the water vapor passes between the particles of the coated sand 2 and penetrates the entire inside of the mold 1 so that the coated sand 2 in the mold 1 can be heated to a uniform temperature. The water vapor blown from the injection port 11 into the mold 1 is exhausted from the exhaust port 13 after heating the coated sand 2 in the mold 1.

In this way, the coated sand 2 is rapidly heated by the latent heat of the steam blown into the mold 1 so that the binder of the coated sand 2 can be solidified or cured in a short time, thereby shortening the molding time of the mold. Is something that can be done. After finishing the step of forming the mold by solidifying or curing the binder of the coated sand 2 in the mold 1 in this way, the connection nozzle 54 of the water vapor supply path 4 is removed from the inlet 11 of the mold 1, The storage tank 14 is connected to the inlet 11 again as described above, and the process returns to the step of filling the mold 1 with the coated sand 2.

Here, as described above, the mold 1 is heated so that the temperature does not decrease by passing water vapor through the mold heating channel 5. Accordingly, in heating the coated sand 2 by blowing water vapor into the mold 1 in the mold making process, it is possible to prevent part of the heat of the water vapor from being lost to the mold 1. The heating efficiency of the coated sand 2 can be maintained high, and the molding time of the mold can be further shortened.

Further, as described above, the coated sand 2 supplied from the storage tank 14 to the mold 1 is preheated by the preheater 40. Accordingly, in the initial blowing steam into the mold 1, prevents the latent heat of the water vapor is absorbed by the coated sand 2, which water vapor can be prevented from being condensed in the mold 1, coated with steam The heating efficiency of the sand 2 can be maintained high, and the molding time of the mold can be shortened.

The steam is blown into the mold 1 only in the process of forming the mold by heating the coated sand 2 in the mold 1. As described above, the steam generated by the steam generator 3 is used as the mold. The mold 1 is heated and the coated sand 2 in the storage tank 14 is heated. The mold 1 and the coated sand 2 are heated only in the mold making process. Not only that, the process of filling the coated sand 2 into the mold 1 is always performed. Therefore, even if the water vapor is always generated by the water vapor generating device 3, the water vapor can be effectively used outside the process of molding the mold, and the water vapor is wasted in other than the mold molding process. Lost
Water vapor can always be used effectively.

FIG. 3 shows another embodiment of the preheater 40 that preheats the coated sand 2 in the storage tank 14 by using heated air as a heating fluid generated by the preheating heat exchanger 42. In the lower part of the storage tank 14, an intermediate partition floor 57 that partitions the inside of the storage tank 14 up and down is provided. The partition floor 57 is composed of a pair of shutter plates 57a and 57a divided into two in the width direction, and the shutter plates 57a and 57a are attached to the storage tank 14 so as to be rotatable by a rotation shaft 58. Each shutter plate 57a is provided with a large number of ventilation holes 59 that open up and down over the entire surface. The inner diameter of the vent hole 59 is formed to be smaller than the particle size of the coated sand 2. When the shutter plates 57a, 57a are in a horizontal state, the partition plate 57 is provided to partition the storage tank 14 up and down. The coated sand 2 supplied to the storage tank 14 is stored on the partition plate 57. Further, when the shutter plates 57a and 57a are rotated downward about the rotation shaft 58, the shutter plates 57a and 57a can be opened in the double-opening state. A hot air discharge nozzle 61 having a large number of discharge ports 62 is provided in the storage tank 14 below the partition wall 57. The other end of the above-described heating fluid supply path 48 having one end connected to the preheating heat exchanger 42 is connected to the hot air discharge nozzle 61.

The preheater 40 is formed by including the partition wall 57 provided with the vent hole 59 and the hot air discharge nozzle 61. As described above, the air heated in the heat exchange chamber 45 of the preheating heat exchanger 42 is sent to the heating fluid supply path 48, and after this heating air passes through the heating fluid supply path 48. When supplied to the hot air discharge nozzle 61, heated air is discharged from the discharge port 62 of the hot air discharge nozzle 61 into the storage tank 14. The heated air discharged into the storage tank 14 rises through the vent holes 59 of the partition wall 57, and the heated air passes between the particles of the coated sand 2 stored on the partition wall 57. In addition, the coated sand 2 can be preheated by heating the coated sand 2 with heated air.

When the mold 1 is filled with the coated sand 2 preheated in the storage tank 14 as described above, the shutter plates 57a and 57a constituting the partition wall 57 are rotated downward to be opened, The coated sand 2 can be performed by flowing down to the nozzle port 17 with the cock 39 and supplying it to the mold 1 from the nozzle port 17.

  FIG. 4 shows an example of another embodiment of the present invention. The mold 1 is formed in the same manner as the embodiment of FIG. 1 described above, and the water vapor generator 3 is also formed in the same manner as the embodiment of FIG. 1 and FIG. 2 described above. In the embodiment of FIG. 4, in addition to branch connection of the steam supply path 4 to the steam delivery path 30 of the steam generator 3, a heat exchange steam supply path 65 is branched and connected. Reference numeral 66 denotes an on-off valve provided in the heat exchange steam supply passage 65.

  The heat exchange steam supply path 65 is connected to the heat exchanger 7. The heat exchanger 7 is formed with a heat exchange chamber 68 through a heat exchange pipe 67, and the heat exchange steam supply path 65 is connected to one end of the heat exchange chamber 68. One end of a steam return path 69 is connected to the other end of the heat exchange chamber 68, and the other end of the steam return path 69 is connected in a branched state to the water introduction path 27 of the steam generator 3. Reference numeral 70 denotes an on-off valve provided in the water vapor return path 69. The heat medium supply path 72 is connected to the inlet 71 at one end of the heat exchange pipe 67, and the heating fluid supply path 6 is connected to the outlet 73 at the other end of the heat exchange pipe 67. As in the embodiment of FIG. 1, the heating fluid supply path 6 is connected to the inlet 22 of the mold heating flow path 5 of the mold 1 by heating fluid supply branch paths 6a and 6a at the tip thereof. One end of a heat medium return path 74 is connected to the outlet 23 of the mold heating flow path 5, and the other end of the heat medium return path 74 is connected to a heat medium tank 75. The other end of the heat medium supply path 72 having one end connected to the inlet 71 of the heat exchange pipe 67 is connected to the heat medium tank 75, and a circulation pump 76 is provided in the heat medium supply path 72. The heat medium tank 75 stores a liquid heat medium. Although it does not specifically limit as such a heat medium, For example, ethylene glycol, diethylene glycol, glycerol, mineral oil, etc. can be used. Specific examples of commercially available products include “Therm S” (alkyl naphthalene, diphenyl diphenyl ether, alkyl diphenyl ether, hydrogenated triphenyl) manufactured by Nippon Steel Chemical Co., Ltd.

  In the apparatus of FIG. 4, by operating the circulation pump 76, the heat medium in the heat medium tank 75 is supplied to the heat exchange pipe 67 of the heat exchanger 7 through the heat medium supply path 72. On the other hand, the steam generated by the steam generator 3 is supplied from the steam delivery path 30 to the heat exchange chamber 68 of the heat exchanger 7 through the heat exchange steam supply path 65. When the steam is supplied to the heat exchange chamber 68 in this way, the heat medium supplied to and passed through the heat exchange pipe 67 is heat-exchanged with the steam and heated. The heated heat medium is sent from the heat exchange pipe 67 to the heating fluid supply path 6 as a heating fluid. The heated heat medium flows from the heating fluid supply path 6 into the mold heating flow path 5 of the mold 1 and can heat the mold 1 when passing through the mold heating flow path 5. . In this way, the mold 1 can be preheated in the same manner as in FIG. 1 described above, and the heat medium sent from the mold heating flow path 5 generates heat by heating the mold 1. The temperature is decreased due to the deprivation and is returned to the heat medium tank 75 through the heat medium return path 74. The steam supplied from the heat exchange steam supply path 65 to the heat exchange chamber 68 goes out to the steam return path 69 after passing through the heat exchange chamber 68, but heat is taken away to heat the heat medium. Since the temperature is lowered, the water is returned from the water introduction path 27 to the boiler 25 and is again regenerated into steam.

  As described above, in the apparatus of FIG. 4, the heat medium is heated by exchanging heat with the water vapor supplied from the water vapor generator 3, and the mold 1 is preheated with the heated heat medium. . Even in this case, it is possible to further shorten the molding time of the mold by preheating the mold 1, and the mold is formed from the water vapor generated by the water vapor generating device 3. It can be used effectively outside of the process.

  FIG. 5 shows an example of another embodiment of the present invention. The preheater 40 including the storage tank 14 and the preheating pipe 40a is formed in the same manner as the embodiment of FIG. 2 described above, and the water vapor generator 3 is also the same as the embodiment of FIG. 1 and FIG. Is formed. In the embodiment shown in FIG. 2, the preheating heat exchanger 42 is formed so as to send out air as a heating fluid, but in the embodiment shown in FIG. 5, the heat medium is sent out as heating fluid.

  That is, the preheating steam supply path 41 connected to the steam delivery path 30 of the steam generator 3 is connected to the preheating heat exchanger 42. The preheating heat exchanger 42 of the embodiment of FIG. 5 is formed with a heat exchange chamber 81 through a heat exchange pipe 80, and the preheating water vapor supply path 41 is one end of the heat exchange chamber 81. Is connected to. One end of a steam return path 82 is connected to the other end of the heat exchange chamber 81, and the other end of the steam return path 82 is connected to the water introduction path 27 of the steam generator 3 in a branched state. 83 is an on-off valve provided in the water vapor return path 82. A heat medium supply path 85 is connected to an inlet 84 at one end of the heat exchange pipe 80, and a heating fluid supply path 48 is connected to an outlet 86 at the other end of the heat exchange pipe 80. The heating fluid supply path 48 is connected to the inlet 50 of the preheating pipe 40 a constituting the preheater 40. One end of the heat medium return path 88 is connected to the outlet 53 of the preheating pipe 40 a, and the other end of the heat medium return path 88 is connected to the heat medium tank 89. The other end of the heat medium supply path 85 having one end connected to the inlet 84 of the heat exchange pipe 80 of the heat exchanger for preheating 42 is connected to the heat medium tank 89, and the heat medium supply path 85 includes a circulation pump. 90 is provided. The heat medium tank 89 stores the liquid heat medium as described above.

In the apparatus of FIG. 5, the heat medium in the heat medium tank 89 is supplied to the heat exchange pipe 80 of the preheating heat exchanger 42 through the heat medium supply path 85 by operating the circulation pump 90. On the other hand, the steam generated by the steam generator 3 is supplied from the steam delivery path 30 to the heat exchange chamber 81 of the preheating heat exchanger 42 through the preheating steam supply path 41. When water vapor is supplied to the heat exchange chamber 81 in this way, the heat medium supplied to and passed through the heat exchange pipe 80 is heat-exchanged with water vapor and heated. The heated heat medium is sent from the heat exchange pipe 80 to the heating fluid supply path 48 as a heating fluid. The heated heat medium flows from the heating fluid supply path 48 into the preheating pipe 40a provided in the storage tank 14, and can heat the coated sand 2 in the storage tank 14 when passing through the preheating pipe 40a. is there. In this manner, the coated sand 2 can be preheated in the same manner as in FIG. 2 described above, and the heat medium sent out from the preheating pipe 40a is deprived of heat by heating the coated sand 2. The temperature is lowered, and it is returned to the heat medium tank 89 through the heat medium return path 88. Further, the steam supplied from the preheating steam supply path 41 to the heat exchange chamber 81 passes through the heat exchange chamber 81 and then goes out to the steam return path 82. Is reduced, the water is returned from the water introduction path 27 to the boiler 25 and is regenerated again into water vapor.

As described above, in the apparatus of FIG. 5, the heat medium is heated by exchanging heat with the steam supplied from the steam generator 3, and the coated sand 2 in the storage tank 14 is preheated with the heated heat medium. It is a thing. Even in this case, it is possible to further shorten the molding time of the mold by preheating the coated sand 2, and the mold is formed from the water vapor generated by the steam generator 3. It can be used effectively outside of the process.

DESCRIPTION OF SYMBOLS 1 Mold 2 Coated sand 3 Water vapor generation device 4 Water vapor supply path 5 Type heating flow path 6 Heating fluid supply path 7 Heat exchanger 8 Superheater
10 cavity 14 storage tank
30 Steam delivery path
36 Steam return path 40 Preheater
65 Steam supply path for heat exchange
69 Steam return path

Claims (7)

A mold for forming a mold having a cavity filled with a coated sand prepared by mixing a binder with a refractory aggregate and water vapor for heating the coated sand filled in the cavity of the mold are generated. In a mold manufacturing apparatus equipped with a steam generator, a steam delivery path for delivering steam generated by the steam generator and a branch connection to the steam delivery path are provided, and the cavity of the mold is filled with coated sand A steam supply path for supplying water vapor into the cavity later, a mold heating path provided in the mold for heating the mold by passing a heating fluid, and a branch connection to the water vapor delivery path separately from the steam supply path the provided by connecting the tip to the mold heating channel of the mold, the heating fluid supply path that transmits the mold heating flow path of steam as a heating fluid as well as, with Mold manufacturing apparatus characterized by comprising. The apparatus for producing a mold according to claim 1 , wherein the water vapor sent out from the water vapor delivery path is constantly supplied to the mold heating flow path through the heating fluid supply path. 3. The mold manufacturing apparatus according to claim 1, further comprising a water vapor return path that returns the water vapor that has passed through the mold heating flow path to the water vapor generator. 4. A mold for forming a mold having a cavity filled with a coated sand prepared by mixing a binder with a refractory aggregate and water vapor for heating the coated sand filled in the cavity of the mold are generated. In a mold manufacturing apparatus equipped with a steam generator, a steam delivery path for delivering steam generated by the steam generator and a branch connection to the steam delivery path are provided, and the cavity of the mold is filled with coated sand A water vapor supply path for supplying water vapor into the cavity later, a mold heating flow path provided in the mold for heating the mold by passing a heating fluid, a heat exchanger, and a water vapor supply path separately from the water vapor supply path A heat exchange water vapor supply passage that is branched and connected to the delivery passage and is connected to the heat exchanger, and the heat exchange water provided between the heat exchanger and the mold heating passage of the mold. A heating fluid supply path for sending a heating medium heated by exchanging heat with steam supplied to the heat exchanger through the air supply path to the mold heating flow path as a heating fluid. manufacturing device. The apparatus for producing a mold according to claim 4 , further comprising a water vapor return path for returning the water vapor that has passed through the heat exchanger to the water vapor generator. The said steam generator is provided with a superheater, The said steam is superheated steam produced | generated by overheating with a superheater, The manufacturing apparatus of the mold in any one of the Claims 1 thru | or 5 characterized by the above-mentioned. It comprises a preheater for preheating the coated sand, and comprises a heating fluid supply passage for sending heated fluid heated by exchanging heat with steam delivered from the steam generator through the steam delivery passage to the preheater. The mold manufacturing apparatus according to any one of claims 1 to 6 .

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