JP4863720B2 - FIBER MOLDING FOR MANUFACTURING CASTING, PROCESS FOR PRODUCING THE SAME AND DEVICE - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fiber molded article which can prevent the absorption of moisture and the adhesion of casting sand to the surface of a cast article and can stably and efficiently be produced. <P>SOLUTION: This fiber molded article is characterized by scattering a moisture-absorbing inhibitor on the outer surface of a fiber molded article body containing a resin component. The moisture-absorbing inhibitor is preferably a silicone-mold release agent. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

  The present invention relates to a fiber molded body for producing a casting and a method for producing the same.

  The applicant has proposed a technique described in Patent Document 1 below regarding a technique for dry-molding a wet fiber laminate containing a resin component in a cavity of a mold to produce a desired fiber molded body.

JP 2004-195547 A

  By the way, since the fiber molded body obtained by the above technique is often used by being embedded in foundry sand, there is a problem that moisture existing in the foundry sand is absorbed to reduce the strength of the fiber molded body. It was. In addition, the moisture absorbed has caused problems such as occurrence of blowback during casting or generation of decomposition gas, resulting in deterioration of the quality of the resulting casting.

  The present invention has been made in view of the above-described problems, and is capable of preventing moisture absorption to the fiber molded body, and can be stably and efficiently manufactured. The purpose is to provide.

  The present inventors have found that the fiber molded body obtained by applying a release agent to the molding surface of the mold of the fiber molded body is difficult to absorb moisture, and completed the present invention.

  This invention is made | formed based on the said knowledge, and provides the fiber molded object for casting manufacture in which the moisture absorption inhibitor is scattered on the outer surface of the fiber molded object main body containing a resin component.

  The present invention also relates to a method for producing a fiber molded body for producing a casting according to the present invention, wherein after forming a wet fiber laminate, the molding of the mold is performed when the fiber laminate is dry-molded. The present invention provides a method for forming a fiber molded body for casting production, in which the moisture absorption inhibitor is applied to the surface in advance and then the fiber laminate is dry-molded.

  Further, the present invention is a method for producing a fiber molded body for producing a casting according to the present invention, wherein after making a wet fiber laminate, the moisture absorption inhibitor is applied to the outer surface of the fiber laminate. Then, a method for forming a fiber molded body for producing a casting for dry-molding the fiber laminate is provided.

  Further, the present invention is a manufacturing apparatus for a fiber molded body for producing a casting according to the present invention, wherein a drying means comprising a paper making means for making a fiber laminate and a forming die for dry-molding the produced fiber laminate. An apparatus for producing a fiber molded body for casting production comprising a molding means and a coating means for applying the moisture absorption inhibitor to the outer surface of the fiber laminate or the molding surface of the mold. is there.

  The fiber molded body for producing a casting according to the present invention can prevent moisture absorption on the surface of the molded body, can prevent adhesion of casting sand, and can be stably and efficiently manufactured. Moreover, according to the manufacturing method and apparatus of the fiber molded object for casting manufacture of this invention, manufacture of the fiber molded object for casting manufacture which show | plays the said effect can be performed suitably.

  The present invention will be described below based on preferred embodiments with reference to the drawings.

First, a preferred embodiment of a fiber molded body for manufacturing a casting according to the present invention (hereinafter also simply referred to as a fiber molded body) will be described.
In the fiber molded body of this embodiment, a moisture absorption inhibitor is scattered on the outer surface of a fiber molded body main body containing a thermosetting resin described later as a resin component. This means that a uniform film is not formed on the surface of the fiber molded body, but is scattered to such an extent that the effects of the present invention, that is, moisture absorption and cast sand adhesion suppressing effect are sufficiently obtained.

  Examples of the moisture absorption inhibitor include silicone release agents and fluorine release agents. Among these, a silicone-based release agent is preferable from the viewpoints of releasability and cost.

  The fiber molded body of this embodiment contains an organic fiber, an inorganic fiber, and a binder.

The organic fiber forms a skeleton in a state before being used for casting in a fiber molded body, and a part or all of it is burned by the heat of molten metal at the time of casting to form a void inside the papermaking part after casting production. .
Examples of the organic fibers include paper fibers, fibrillated synthetic fibers, regenerated fibers (for example, rayon fibers) and the like, and these are used alone or in combination of two or more. Among these, paper fiber is preferable. The reason for this is that paper fibers are easily available and stable, the manufacturing cost of the molded body is reduced, the paper body can be formed into various forms by papermaking, and the dehydrated and dried molded body has sufficient strength. .

  In addition to wood pulp, cotton pulp, linter pulp, bamboo straw and other non-wood pulp can be used for the paper fiber. Virgin pulp or waste paper pulp (collected product) can be used alone or in combination of two or more. Waste paper pulp is particularly preferred from the standpoints of availability, stability, environmental protection, and reduction in production costs.

  The average fiber length of the organic fiber is preferably 0.8 to 2.0 mm, and more preferably 0.9 to 1.8 mm. If the average fiber length of the organic fibers is too short, the surface of the molded body may be cracked, or mechanical properties such as impact strength may be inferior. It may get worse.

  10-70 mass parts is preferable, and, as for content of the said organic fiber, 20-60 mass parts is more preferable. In addition, in this specification, a mass part means the value with respect to a total of 100 mass parts of an organic fiber, an inorganic fiber, and a binder. If the content of organic fiber is too small, the formability of the fiber molded product may deteriorate due to the lack of organic fibers forming the skeleton of the fiber molded product, and the strength of the fiber molded product after dehydration or drying may be insufficient. If the amount is too high, a large amount of combustion gas is generated during pouring, causing blow-back from the pouring gate, or frying (a thin rod-shaped gap provided at the top of the mold, and the molten metal rises to the top of the mold after filling the mold. In some cases, a fiery flame may come out from the part to be manufactured, and the manufacturing cost may be high depending on the fiber used.

  The inorganic fiber mainly forms a skeleton in a state before being used for casting in a fiber molded body, and maintains its shape without being burned by the heat of molten metal during casting. In particular, when an organic binder, which will be described later, is used as the binder, the inorganic fibers can suppress thermal shrinkage caused by thermal decomposition of the organic binder due to the heat of the molten metal.

  Examples of the inorganic fibers include carbon fiber, artificial mineral fibers such as rock wool, ceramic fibers, and natural mineral fibers, which are used alone or in combination of two or more. Among these, it is preferable to use a carbon fiber having high strength even at a high temperature from the viewpoint of suppressing the heat shrinkage. Moreover, it is preferable to use rock wool from the viewpoint of reducing manufacturing costs.

  The average fiber length of the inorganic fibers is preferably 0.2 to 10 mm, and more preferably 0.5 to 8 mm. If the average fiber length of the inorganic fibers is too short, drainage may be reduced and dewatering may occur during the manufacture of the papermaking part. Moreover, papermaking property may fall at the time of manufacture of a thick fiber molded object (especially hollow solid shape thing like a bottle). On the other hand, if the average fiber length of the inorganic fibers is too long, there is a possibility that a fiber molded body having a uniform thickness may not be obtained, and it may be difficult to produce a hollow fiber molded body.

  1-80 mass parts is preferable and, as for content of the said inorganic fiber, 4-40 mass parts is more preferable. If the content of the inorganic fiber is too small, the strength at the time of casting of the fiber molded body produced using an organic binder is lowered, and the shrinkage, cracking, and peeling of the wall surface due to carbonization of the binder ( There is a risk that the wall surface of the papermaking part will be separated into an inner layer and an outer layer. Furthermore, a defective product may be manufactured by mixing a part of the fiber molded body or casting sand into the product (casting). If the content of the inorganic fiber is too large, the formability of the fiber molded body particularly in the paper making process or the dehydration process is lowered, and the part cost may be increased depending on the fiber used.

  The ratio of the inorganic fiber to the organic fiber (inorganic fiber content / organic fiber content) is a mass ratio. For example, when the inorganic fiber is carbon fiber, 0.15 to 50 is preferable, and 0.25 to 30 is more preferable. preferable. When inorganic fiber is rock wool, 10-90 are preferable and 20-80 are more preferable. If there are too many inorganic fibers, the formability of the fiber molded body in papermaking and dehydration molding will deteriorate, the strength of the fiber molded body after dehydration will be insufficient, and the fiber molded body may crack when taken out from the papermaking mold. . When there are too few inorganic fibers, a fiber molded object may shrink | contract due to the thermal decomposition of an organic fiber and the below-mentioned organic binder.

  Examples of the binder include an organic binder and an inorganic binder as described later. The organic binder and the inorganic binder can be used alone or in combination.

  The organic binder may be added to the raw material slurry of the fiber molded body, or may be impregnated into the manufactured fiber molded body. When added to the raw material slurry, since the binder binds the organic fiber and the inorganic fiber when the fiber molded body is dried, a high-strength fiber molded body can be obtained. However, when it is added to the raw material slurry, the dry mold may be easily soiled with a binder. As said organic binder, thermosetting resins, such as a phenol resin, an epoxy resin, and a furan resin, are mentioned. Among these, it is particularly preferable to use a phenol resin from the viewpoints that the generation of combustible gas is small, there is a combustion suppressing effect, and the residual carbon ratio after pyrolysis (carbonization) is high. The said organic binder is used individually or in combination of 2 or more types.

The inorganic binder is one that binds the organic fiber and the inorganic fiber when the paper-made part is dry-molded before casting, the one that remains at the time of casting and has the effect of suppressing the generation of combustion gas and flame, There are those that melt by heat and exhibit the ability as a binder, and those that have the effect of preventing so-called carburizing during casting.
Examples of the inorganic binder include compounds containing SiO ₂ as a main component such as colloidal silica, obsidian, nacre, ethyl silicate, and water glass. Among these, it is particularly preferable to use colloidal silica from the standpoints that it can be used alone and is easy to apply. In view of the points that can be added to the raw slurry and the prevention of carburization, it is preferable to use obsidian. The said inorganic binder is used individually or in combination of 2 or more types.

  10-85 mass parts is preferable and, as for content of the said binder (solid content), 20-80 mass parts is more preferable. If the binder content is too small, pinholes may be generated in the papermaking part and the compression strength of the fiber molded body may be reduced. When the organic binder is used, the strength of the fiber molded body may be insufficient when pouring and casting sand may be mixed into the product. If the content of the binder is too large, the fiber molded body may stick to the mold during the dry molding after paper making, which may hinder the separation of the fiber molded body from the mold.

When a binder other than obsidian is used, the content of the binder is preferably 10 to 70 parts by mass, and more preferably 20 to 50 parts by mass.
When obsidian is used as the binder, it is preferable to include at least 20 parts by mass of obsidian in the total binder. Only obsidian can be used as the binder.

  In the production of the papermaking part for casting production according to this embodiment, a curing agent is required when a novolak phenol resin is used. Since the curing agent is easily soluble in water, it is preferably applied to the surface of the papermaking part after dehydration. It is preferable to use hexamethylenetetramine or the like as the curing agent.

Further, as the binder, two or more types having different melting points or thermal decomposition temperatures can be used in combination. In particular, from the standpoint of maintaining the shape of the fiber molded body when it is exposed to a high temperature during casting from before casting at room temperature, and preventing carburization during casting, a low melting binder and a high melting point are used. Use of a binder is preferred. In this case, examples of the low melting point binder include clay, water glass, obsidian, and the like, and examples of the high melting point binder include colloidal silica, wollastonite, mullite, and Al ₂ O ₃ . Examples of combinations of binders having different melting points or thermal decomposition temperatures include a combination of obsidian and a phenol resin. Obsidian has a melting point of 1200 ° C. to 1300 ° C., and a thermal decomposition temperature of phenol resin is about 500 ° C. (The result of mass loss measurement in nitrogen gas (DTA) shows that 40 wt% of phenol resin decomposes, about 50% decomposes at about 500 ° C).

  In addition to the organic fiber, the inorganic fiber, and the binder, a paper strength reinforcing material may be added to the papermaking part for casting production according to the present embodiment. The amount of the paper strength reinforcing material used is preferably 1 to 20%, particularly 2 to 10% of the total mass of the fibers. If there is too little paper strength reinforcing agent, the above-mentioned swelling prevention may be insufficient, or the added powder may not be fixed to the fiber, and even if added in large quantities, the effect will not improve and the molded body of the papermaking part will become a mold It may become easy to stick. Examples of the paper strength reinforcing material include polyvinyl alcohol, carboxymethyl cellulose (CMC), and polyamidoamine epichlorohydrin resin.

  Components such as a flocculant and a colorant can be further added to the fiber molded body of the present embodiment.

  Although the thickness of the said fiber molded object can be set according to a use purpose etc., 0.2-5 mm is preferable and, as for the thickness of the part which contacts a molten metal at least, 0.4-3 mm is more preferable. If it is too thin, the strength as a fiber molded body becomes insufficient, and it may be difficult to maintain the shape and function desired for the fiber molded body under the pressure of casting sand. If it is too thick, the air permeability is impaired, the raw material cost is increased, the molding time is increased, and the production cost may be increased.

  The fiber molded body preferably has a compressive strength of 10N or more, more preferably 30N or more before being used for casting. If the compressive strength is too low, it may be deformed by being pressed by foundry sand, and the function as a papermaking part may be impaired.

  When the fiber molded body is produced using a raw material slurry containing water, the mass moisture content before use of the fiber molded body (before being used for casting) is preferably 10% or less, more preferably 8% or less. preferable. The reason is that the lower the water content, the lower the amount of gas generated due to the thermal decomposition (carbonization) of the organic binder during casting.

  The specific gravity before use of the fiber molded body is preferably 1.0 or less, and more preferably 0.8 or less. The reason is that if the specific gravity is small, the weight becomes light and the handling and processing of the fiber molded body becomes easy.

Next, the manufacturing method and apparatus of the fiber molded body of this invention are demonstrated based on the preferable embodiment.
1 to 4 schematically show an embodiment of a production apparatus for carrying out the method for producing a fiber molded body of the present invention. In these drawings, reference numeral 1 denotes a fiber molded body manufacturing apparatus (hereinafter also simply referred to as an apparatus).

  As shown in FIGS. 1 and 2, the apparatus 1 of this embodiment includes a pair of split molds 20, 20 ′, and a papermaking mold (papermaking means) 2 for making a fiber laminate, a split mold 30, A dry mold (molding means) 3 that molds the fiber laminate that has been made and made 30 ′, and a coating means 4 that coats the moisture absorption inhibitor on the molding surface of the dry mold 3 are provided.

  Further, the apparatus 1 adsorbs the fiber laminate 10 to the molding surfaces of the split mold and the dry mold 3 and a position moving means (not shown) for moving the split molds 20, 20 ′, 30, 30 ′. A suction means (not shown) and a control means (not shown) for controlling the position moving means and the suction means are provided.

  As shown in FIG. 3, in the apparatus 1, the papermaking mold 2 and the dry mold 3 are arranged in parallel so as to be adjacent to each other, and the split mold 20 and the split mold 30 are fixed to the platen 5. . The split mold 20 'and the split mold 30' are arranged so as to face the corresponding split mold.

  The position moving means includes a drive mechanism (not shown) for moving the split molds 20 ′ and 30 ′ in a direction perpendicular to the opening and closing directions of the papermaking mold 2 and the drying mold 3, and the split molds 20, 20 ′ and the split mold. And a mold clamping mechanism (not shown) for clamping the molds 30 and 30 ′ with each other and clamping the molds in the direction perpendicular to the moving direction of the split molds 20 ′ and 30 ′. The papermaking mold 2 and the dry mold 3 can be opened and closed by moving the.

  As shown in FIG. 2, the papermaking mold 2 has a cavity C formed therein by the split molds 20 and 20 'being butted against each other. Since the split molds 20 and 20 'have basically the same configuration except that they are formed symmetrically, only the split mold 20 will be described in the following description.

  The split mold 20 includes a papermaking mold body 200 and a frame 210 that forms a predetermined space between the papermaking mold body 200 and covers the outside of the papermaking mold body 200. A partition 220 that divides this space into three rooms S1 to S3 is disposed between the papermaking mold main body 200 and the frame body 210. The papermaking mold main body 200 is formed with a large number of fluid flow holes 201 that allow the space and the cavity C to communicate with each other.

  On the cavity forming surface 202 of the split mold 20, fluid circulation grooves 203 having a predetermined width are formed in a lattice shape so as to connect the fluid circulation holes 201. A papermaking net (not shown) having a predetermined opening and a wire diameter is disposed on the cavity forming surface 202 of the papermaking mold body 200.

  The frame 210 is formed with fluid flow passages 211 that communicate the respective rooms S1 to S3 with the outside, and these fluid flow passages 211 are connected to a negative pressure source and a compressor via a switching valve. Pipe lines (both not shown) are connected. The split mold 20 can suck and depressurize the cavity C through these fluid circulation holes 201 and the fluid flow passage 211 or supply pressurized fluid into the cavity. The apparatus can be miniaturized by supplying pressurized fluid to the inside through a single path.

  In the apparatus 1 of the present embodiment, the negative pressure source and the pipe line communicating with the negative pressure source, the fluid circulation groove 203, the fluid circulation hole 201, and the fluid flow path 211 also serve as the suction means.

  The drying die 3 has a heating means (not shown), and basically has the same configuration as the paper making die 2 except that the paper making net and the fluid circulation groove are not provided. Yes.

  As shown in FIG. 3, the drying mold 3 has a cavity C ′ formed therein by the split molds 30 and 30 ′ being butted against each other. Since the split molds 30 and 30 ′ have basically the same configuration except that they are formed symmetrically, only the split mold 30 will be described in the following description.

  The split mold 30 includes a mold body 300 and a frame 310 that forms a predetermined space between the mold body 300 and covers the outside of the mold body 300. A partition 320 that partitions this space into three rooms S10 to S30 is disposed between the mold body 300 and the frame 310. A large number of slit-like fluid circulation holes 301 having a predetermined width are formed in the mold body 300 to communicate this space with the cavity C ′.

  The frame 310 is formed with fluid flow passages 311 that communicate the respective rooms S10 to S30 with the outside. The fluid flow passages 311 are connected to a negative pressure source and a compressor via a switching valve. Pipe lines (both not shown) are connected. The split mold 30 is configured to be able to suck and depressurize the cavity or supply pressurized fluid into the cavity through the fluid flow hole 301 and the fluid flow passage 311. The apparatus can be reduced in size by supplying the pressurized fluid to the apparatus through a single path.

  In the apparatus 1 of the present embodiment, the negative pressure source and the pipe line leading to the negative pressure source, the fluid circulation hole 301 and the fluid flow passage 311 also serve as the suction means.

  As shown in FIG. 2, the coating means 4 includes a tank 40 in which the inhibitor is stored, a nozzle 41 disposed so as to close the opening 31 of the drying mold 3, and the tank 40 and the nozzle 41. A supply pipe 42 to be connected and a rotation mechanism 43 for rotating the nozzle 41 around a horizontal axis are provided.

  The control means includes a sequencer, and the device 1 operates according to the sequence described below.

  Next, a preferred embodiment of the method for producing a fiber molded body of the present invention will be described based on the method for producing a fiber molded body using the apparatus 1 with reference to the drawings.

First, as shown in FIG. 1 , the raw slurry is injected under pressure from the opening 21 at the upper part of the papermaking mold 2 with the split molds 20, 20 ′ of the papermaking mold 2 butted against each other and the cavity C is formed. Is done. A pressure feed pump is used for pressure injection of the raw slurry. In the raw material slurry, the inorganic fiber, the organic fiber, the binder and the like are appropriately blended at a predetermined ratio.

  When the raw material slurry is injected until the amount of slurry in the cavity C reaches a predetermined amount, suction / drainage of the raw material slurry through the fluid circulation groove 203, the fluid circulation hole 201, and the fluid flow passage 211 is started. As a result, the liquid content in the raw slurry is discharged out of the papermaking mold 2 and the solid content is deposited on the papermaking net, and the fiber laminate 10 (see FIG. 3A) is made.

  After the fiber laminate having a predetermined thickness is formed, the supply of the slurry through the opening 21 is completed, and the inside of the cavity C is continuously sucked and decompressed through the fluid circulation groove 203, the fluid circulation hole 201, and the fluid circulation passage 211. At the same time, compressed air (heated air) is supplied into the cavity C through the opening 21 to dehydrate the fiber laminate to a predetermined moisture content.

  When the fiber laminate is dehydrated to a predetermined moisture content, the supply of compressed air into the cavity C through the opening 21 and the decompression of the cavity C through the fluid circulation hole 201 and the fluid flow passage 211 are stopped.

  While the fiber laminate is being made by the papermaking mold 2 as described above, in the dry mold 3, as shown in FIG. 3A, the split molds 30 and 30 ′ are abutted and the dry mold 3 is closed. In this state, the moisture absorption inhibitor is applied to the molding surface 302 by the coating means 4.

  Next, the process of transferring the wet fiber laminate 10 containing the resin component produced in the papermaking mold 2 to the dry mold 3 will be described with reference to FIGS.

  First, in the state of FIG. 3A, the fiber laminate 10 is formed into a cavity of the split mold 20 ′ by suction and decompression through the fluid flow groove 203, the fluid flow hole 201 and the fluid flow passage 211 of the split mold 20 ′. In a state where compressed air is blown to the fiber laminate 10 from the cavity forming surface 202 (inner surface) of the split mold 20 through the fluid circulation hole 201 and the fluid flow passage 211, it is adsorbed by the surface (inner surface) 202. The split mold 20 ′ is retracted so that the fiber laminate 10 is separated from the cavity forming surface 202. And as shown in FIG.3 (b), the papermaking type | mold 2 opens and the fiber laminated body 10 is transferred to the split type 20 'side. When the papermaking mold 2 is opened, the blowing of compressed air to the fiber laminate 10 is stopped.

  Next, as shown in FIG. 3 (c), the split molds 20 ′ and 30 ′ are moved in a direction (lateral direction) perpendicular to the clamping direction, and the split mold 20 ′ is moved to a position facing the split mold 30. Then, as shown in FIG. 3 (d), the split mold 20 ′ is abutted against the split mold 30. Then, the fiber laminate 10 is sucked to the split mold 30 side through the fluid circulation hole 301 and the fluid flow passage 311. Then, as shown in FIG. 3E, the split mold 20 ′ is moved away from the split mold 30. At this time, compressed air is injected through the fluid flow passage 211, the fluid flow groove 203 and the fluid flow hole 201 of the split mold 20 '. Then, the fiber laminate 10 is transferred to the split mold 30.

  Next, as shown in FIG. 3 (f), the split molds 20 ′ and 30 ′ are moved to a position facing the split molds 20 and 30. Then, as shown in FIG. 4A, the split molds 20 ′ and 30 ′ are abutted against the split molds 20 and 30 ′. In the papermaking mold 2, the fiber laminate 10 is newly made. The fiber laminate 10 is dry-molded as described below.

  That is, first, the dry mold 3 heated to a predetermined temperature through the fluid flow hole 301 and the fluid flow passage 311 is sucked and depressurized from the inside toward the outside, and the core made of a hollow bag-like elastic body. 32 is inserted into the fiber laminate 10. The core 32 is used to give the shape of the molding surface 302 by inflating like a balloon in the cavity C ′ and pressing the wet fiber laminate 10 against the molding surface 302 of the dry mold 3. The The core 32 is preferably formed of a flexible film such as fluorine rubber, silicone rubber, or elastomer having excellent tensile strength, impact resilience, and stretchability.

  Next, pressurized fluid is supplied into the core 32 to expand the core 32, and the wet fiber laminate 10 is pressed against the molding surface 302 by the expanded core 32. As the pressurized fluid used for expanding the core 32, for example, compressed air (heated air), oil (heated oil), and other various liquids are used.

Fiber laminate 10 is pressed against the molding surface 302 by the expanded core 32, the moisture of the fiber laminate 10 is, fluid flow holes 301, are Aspirate as vapor through the fluid flow passageway 311 is discharged to the outside. Then, as the fiber laminate 10 is dried, the shape of the cavity forming surface 302 is transferred to the outer surface of the fiber laminate 10. At this time, the moisture absorption inhibitor is transferred from the molding surface 302 to the outer surface of the fiber molded body so that the moisture absorption inhibitor is scattered on the outer surface of the obtained fiber molded body.

When the fiber laminate 10 is sufficiently dried to a predetermined moisture content, the pressurized fluid in the core 32 is degassed and the core 32 is reduced. Next, the reduced core 32 is taken out from the fiber laminate 10. Further, the above suction on the split mold 30 side is stopped, and the split mold 30 ′ of the dry mold 3 is opened. Further, the split mold 20 of the papermaking mold 2 'is also opened as in FIG. 3 (b). Then, as shown in FIG. 4 (b), the fiber laminate 10 made by the papermaking mold 2 and the fiber molded body 10 ′ formed in the dry mold 3 are transferred to the split molds 20 ′ and 30 ′, respectively. The

  Next, the split molds 20 ′ and 30 ′ are moved in a direction (lateral direction) orthogonal to the mold clamping direction, and the split mold 20 ′ is moved to a position facing the split mold 30. Then, as shown in FIG. 4 (d), the split mold 30 'is moved to the delivery position with the lower conveyance means (not shown), and the fiber molded body 10' is delivered to the lower conveyance means (not shown). . At this time, compressed air is injected from the split mold 30 ′ through the fluid flow passage 311 and the fluid circulation hole 301.

  Next, as shown in FIG. 4 (e), the split mold 30 ′ that has delivered the fiber molded body 10 ′ is retracted, and as shown in FIG. 4 (f), the split molds 20 ′ and 30 ′ are split into the split mold 20. , 30 and the split mold 30 ′ is abutted against the split mold 30. Then, a moisture absorption inhibitor is applied to the molding surfaces 302 of the split molds 30 and 30 ′ by the coating means 4.

  Thereafter, in the apparatus 1 of the present embodiment, the steps shown in FIGS. 3B to 3F and FIGS. 4A to 4F are repeatedly performed, and the moisture absorption suppression is performed on the outer surface. A fiber molded body in which the agent is dispersed is repeatedly produced.

  As described above, in the method for manufacturing a fiber molded body using the apparatus 1 of the present embodiment, the moisture absorption inhibitor is applied to the molding surface 302 of the dry mold 3 with the split molds 30 and 30 ′ closed. Therefore, the molded body can be manufactured efficiently. Further, since the moisture absorption inhibitor also functions as a release agent, it is possible to prevent the resin component or the like from adhering to the molding surface of the molding die and becoming dirty or clogging the fluid circulation hole 301.

The present invention is not limited to the embodiment.
For example, as shown in FIG. 5A, the nozzle 41 ′ of the coating means 4 for applying the moisture absorption inhibitor is disposed between the split mold 20 ′ and the split mold 30 ′ and outside the split mold 30. May be.

  In this case, as shown in FIG. 5B, the split molds 20 ′ and 30 ′ receive the fiber laminates from the split molds 20 and 30, respectively, and the split mold 20 ′ is opposed to the split mold 30. As shown in FIG. 5C, the nozzle 30 'is temporarily stopped while the split mold 30' is moved to a delivery position with a lower conveying means (not shown). The moisture absorption inhibitor is sprayed from 41 'and the moisture absorption inhibitor is applied. For the split mold 30 ′, as shown in FIG. 5 (d), the split molds 20 ′ and 30 ′ deliver the fiber laminate and the fiber molded body to the split mold 30 and a lower transport means (not shown), After the delivery, as shown in FIG. 5 (e), the split molds 20 ′ and 30 ′ are temporarily stopped while being moved to a position facing the split molds 20 and 30, and FIG. As shown, the moisture absorption inhibitor is sprayed from the nozzle 41 ′ onto the molding surface 302 of the split mold 30 ′ which is empty, and the moisture absorption inhibitor is applied. In this case as well, the same effects as in the above embodiment are achieved.

  Moreover, as shown to Fig.6 (a), you may arrange | position the nozzle 41 'of the coating means 4 which applies a moisture absorption inhibitor to the split molds 20 and 20'.

  In this case, as shown in FIG. 6B, before the split mold 20 'receives the fiber laminate 10 from the split mold 20, the split mold 20 is once retracted so as to separate the fiber molded body. At this time, the moisture absorption inhibitor is sprayed from the nozzle 41 ′ to the outer surface of the fiber laminate 10, and the moisture absorption inhibitor is applied. Then, the split mold 20 ′ is again abutted against the split mold 20, and when the fiber laminate is transferred to the split mold 20 ′ as shown in FIG. 5C, the split mold 20 ′ is temporarily stopped, and the fiber The moisture absorption inhibitor is sprayed from the nozzle 41 ′ to the outer surface of the laminated body 10, and the moisture absorption inhibitor is applied. In this case as well, the same effects as in the above embodiment are achieved.

Hereinafter, the present invention will be described more specifically with reference to examples.
The following fiber laminate was dry molded under the following conditions, and the fiber molded body was molded 1250 times (equivalent to 24 hours operation). Thereafter, the following moisture absorption inhibitor was supplied into the cavity of the emptied mold under the following conditions to purify the mold.

<Fiber laminate>
After making a predetermined fiber laminate using the following raw material slurry, it was dehydrated and dried to obtain a fiber molded body.

<Preparation of raw material slurry>
An organic fiber and an inorganic fiber having the following composition are dispersed in water to prepare a slurry of about 1% (the total mass of the organic fiber and the inorganic fiber is 1% by mass with respect to water). Powder was added, and the following flocculant was further added to prepare a raw material slurry having a mixing ratio (mass ratio) of organic fiber, inorganic fiber, resin binder, and inorganic powder of the following values.

[Combination of raw slurry]
Organic fiber: used newspaper, average fiber length is 1mm, Canadian Standard Freeness (CSF, the same shall apply hereinafter) is 200cc
Inorganic fiber: Carbon fiber (manufactured by Toray Industries, Inc., trade name: “Treka chop”), fiber length 3 mm
Resin binder: Phenolic resin (Bell Pearl, manufactured by Air Water Co., Ltd.)
Inorganic powder: Obsidian Flocculant: Polyacrylamide flocculant (Mitsui Cytec Co., Ltd., A110)
Paper strength enhancer: 1% aqueous solution of carboxymethyl cellulose Dispersion medium: water The above organic fiber / inorganic fiber / resin binder / inorganic powder is mixed to a slurry with a mixing ratio (mass ratio) of 26% / 8% / 18% / 48%. The CSF was adjusted to 250 cc.

<Paper making and dehydration process>
A papermaking mold is a pair of split molds having a cavity forming surface, in which a net having a predetermined mesh is arranged on the cavity forming surface, and a large number of communication holes for communicating the cavity forming surface and the outside are formed. Using.
Then, the raw material slurry is circulated by a Mono pump (uniaxial eccentric screw structure pump), and a predetermined amount of slurry is pressurized and injected into the papermaking mold, while being drained through the communication hole, and a predetermined fiber laminate is transferred to the net. Deposited on the surface. And when injection | pouring of the predetermined amount raw material slurry was completed, pressurized air was inject | poured in the papermaking type | mold and dehydrated. The pressure of the pressurized air was 0.2 MPa and dehydrated for about 30 seconds.

<Dry molding conditions>
As the dry mold, a pair of split molds having a cavity forming surface in which a large number of communication holes communicating the cavity forming surface with the outside were used.
And the said fiber laminated body was taken out from the papermaking type | mold, and it transferred to the dry shaping | molding die heated at 220 degreeC. Then, a bag-shaped elastic core is inserted from the upper opening of the dry mold, and a pressurized fluid (pressurized air, 0.5 MPa) is injected into the elastic core in a sealed dry mold to inflate it. The fiber laminate was pressed against the inner surface of the dry mold and dried while transferring the inner surface shape of the dry mold. After performing pressure drying for a predetermined time (40 seconds), the pressurized fluid in the elastic core is removed, the elastic core is contracted and retracted from the dry mold, and the molded body is removed from the dry mold. I took it out. When such molding was performed about 1250 times, the following moisture absorption inhibitor was supplied into the cavity of the emptied mold under the following conditions.

<Hygroscopic suppression (release) agent coating conditions>
Mold temperature: 220 ° C
Release agent: manufactured by Konishi Co., Ltd., 20-fold dilution of release agent URA-202, release agent coating amount: 30 ml
Application time: 2s
Suction time: 1s
Application frequency: Apply once every 10 shots of molding

<Result>
When the molded body was embedded in foundry sand for about 1 hour and then weighed, it was found that there was no change in weight and no moisture absorption. Moreover, there was no adhesion of foundry sand to the surface of the molded body. In addition, the amount of resin adhering to the slit for escaping the cavity surface, vapor and the like out of the mold has been reduced, and there has been no mistake in delivery of the molded product due to resin adhesion. Furthermore, the cleaning operation of the mold surface performed every 12 hours can be extended up to every 24 hours.

  The molding method of the fiber molded body of the present invention is not limited to parts for casting production such as molds, cores, runner pipes, etc., which are made of the fiber molded body containing the resin component, and the steam vent holes and slits during drying are small and continuous. It is also suitable when it is difficult to remove dirt after molding.

It is a fragmentary sectional view which shows typically one Embodiment of the papermaking type | mold in the manufacturing apparatus of the fiber molded object of this invention. It is a fragmentary sectional view which shows typically one Embodiment of the dry shaping | molding die in the manufacturing apparatus of the fiber molded object of this invention. (A)-(f) is a schematic diagram for demonstrating the manufacturing process of the fiber molded object by one Embodiment of the manufacturing apparatus of the fiber molded object of this invention. (A)-(f) is a schematic diagram for demonstrating the manufacturing process of the fiber molded object by one Embodiment of the manufacturing apparatus of the fiber molded object of this invention. (A)-(e) is a schematic diagram for demonstrating the manufacturing process of the fiber molded object by other embodiment of the manufacturing apparatus of the fiber molded object of this invention. (A)-(c) is a schematic diagram for demonstrating the manufacturing process of the fiber molded object by other embodiment of the manufacturing apparatus of the fiber molded object of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Manufacturing apparatus of fiber molded object 2 Papermaking type | mold (papermaking means)
20, 20 'Split mold 3 Dry mold (dry molding means)
30, 30 'Split mold 302 Molding surface 4 Means for applying moisture absorption inhibitor 10 Fiber laminate 10' Fiber molded body

Claims (1)

A method for producing a fiber molded body for casting production in which moisture absorption inhibitors are interspersed on the outer surface of a fiber molded body main body containing a resin component ,
The moisture absorption inhibitor is a silicone release agent,
After making a wet fiber laminate with a papermaking mold,
When molding the fiber laminate ,
In a state where the dry mold is closed, the mold release agent is applied to the molding surface of the dry mold in advance and suction is performed in the dry mold, and the wet fiber laminate is formed using the core. A method for producing a fiber molded body for producing a casting , wherein the mold is dried while being pressed against the molding surface, and at the same time, the release agent is transferred .

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