JP2010023317A - Method and device for manufacturing hollow molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device suitable for molding a hollow molded article having a complicated shape by an internal pressure molding method. <P>SOLUTION: A baglike body 22 is inserted into a hollow part 2b of a hollow molded substrate 1, and next, a filling material 14 is filled into the hollow part 2b. Pressure liquid is supplied to the baglike body 22 in a cavity space part of a molding mold 11 to expand the baglike body 22. A pressing force of the baglike body 22 is transmitted to the hollow molded substrate 1 through the filling material 14 thereby. The hollow molded substrate 1 is pressed to cavity surfaces 12a, 13a of the molding mold 11 to mold the hollow molded article. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method and apparatus for producing a hollow molded article, and more particularly to a production method and apparatus for producing a hollow molded article using an internal pressure molding method in which a hollow molded substrate is molded by applying internal pressure.

  Fiber Reinforced Resin (FRP) is a combination of thermosetting resin or thermoplastic resin matrix material and reinforced fiber, and is used in many fields because of its light weight and excellent strength characteristics. . Examples of thermosetting resins include unsaturated polyester resins, epoxy resins, polyimide resins, and the like, and examples of thermoplastic resins include polyethylene, polypropylene, polyamide, and the like. Examples of the reinforcing fiber include carbon fiber, glass fiber, and aramid fiber.

  A hollow molded product is also made using a fiber reinforced resin, and one of the molding methods is an internal pressure molding method. In the internal pressure molding method, a bag-shaped body inserted into a hollow portion of a hollow molded substrate is placed in a cavity space of a mold, and a pressurized fluid such as compressed air is fed into the bag-shaped body to form a bag In this method, the body is expanded and the hollow molding substrate is pressed against the cavity surface of the molding die.

  An example of manufacturing a hollow molded product using an internal pressure molding method is described in Patent Document 1. According to Patent Document 1, a molding substrate is wound around a tube that is a bag-like body to form a hollow shape, and is placed between an upper die and a lower die of a molding die and clamped to form a cavity space. Place in the department.

  Then, the inside of the cavity space is decompressed by a vacuum pump and pressurized gas is injected into the tube to expand the tube, and a hollow molding substrate is pressed against the cavity surface to be molded into a desired shape. And after hardening or solidifying the resin contained in the shaping | molding base material, a molded article is taken out from a type | mold, a tube is removed, and the hollow molded article is obtained.

  In Patent Document 1, a molding base material containing a resin is molded in advance. As another internal pressure molding method, for example, a liquid thermosetting resin is injected into a cavity space of a molding die to form a fiber fabric of the molding base material. An RTM molding method in which a layer is impregnated and subjected to internal pressure molding is also conventionally performed.

JP-A-5-329856

  However, in each of the conventional internal pressure molding methods described above, it has been difficult to mold the hollow molded base material into a complicated shape. For example, when the bag-shaped body is made of a thin sheet member of nylon or urethane, the shape following property of the bag-shaped body is poor, and the internal pressure received by the hollow molded base material from the bag-shaped body is each part of the hollow molded base material. However, it was difficult to press the portion of the hollow molded base material that had a complicated shape, and it was difficult to mold the shape along the cavity surface.

  In addition, for example, when the bag-like body is made of a heat-resistant rubber material such as silicone rubber whose shape followability is better than that of nylon or urethane, the bag-like body is locally excessively excessive depending on the complicated shape. May swell and rupture.

  In addition, the bag-like body may enter a complicated shape portion, and the bag-like body may not be taken out from the inside of the hollow molded product after molding, or the bag-like body may be damaged during the taking-out operation. It could not be used repeatedly and was expensive. When all or part of the bag-like body remains inside the hollow molded product, there is a problem that the weight of the hollow molded product is increased by the remaining amount and the weight of the hollow molded product cannot be reduced.

  The present invention has been made in view of the above points, and even if it has a complicated shape, it can be molded without any inconvenience, and after molding, the bag-like body can be easily removed from the hollow portion of the hollow molded product. It is an object of the present invention to provide a method and an apparatus for producing a hollow molded product that can be taken out.

  An invention of a method for manufacturing a hollow molded article for solving the above-described problem is that an internal pressure is applied to a bag-shaped body in a state where a hollow molded base material in which a bag-shaped body is inserted in a hollow portion is disposed in a cavity space portion of a mold. In addition, in the method of manufacturing a hollow molded article using an internal pressure molding method in which the hollow molding base material is pressed against the cavity surface of the molding die and molded, the hollow molding base material is hollowed before the bag-shaped body is inflated. It is characterized by filling the portion with a filler and inflating the bag-like body in a state where the filler is interposed between the bag-like body and the hollow molded substrate.

  According to the present invention, the bag is filled with the filler in the hollow portion of the hollow molded base material, and the bag-shaped body is inflated with the granular material interposed between the bag-shaped body and the hollow molded base material. The internal pressure of the bag-like body can be transmitted to a complicated shape portion that is difficult to be pressed only by the shape-like body through a filler that enters between the shape portion and the bag-like body.

  Accordingly, the internal pressure received by the hollow molded base material from the bag-like body can be made uniform at each part of the hollow molded base material, and all the parts of the hollow molded base material can be pressed against the cavity surface with a uniform pressing force. It can be formed into a shape along the surface. Therefore, even if it has a complicated shape, it can be molded without any inconvenience, and a hollow molded product with good external dimension accuracy can be obtained.

  Further, when the bag-like body is inflated, the bag-like body can be prevented from entering the complicated shape portion of the hollow molded base material, and the bag-like body can be easily taken out from the hollow portion of the hollow molded article after molding. be able to. Therefore, the bag-like body and the filler can be used repeatedly. Moreover, it is not necessary to prepare a bag-like body corresponding to the shape of the hollow molded product, and the bag-like body can have versatility.

  A method for producing a hollow molded article according to the present invention comprises forming a hollow molded substrate having a core having a hollow portion and a fiber fabric layer formed on the outer periphery of the core in a state where a bag-like body is inserted into the hollow portion. Place in the cavity space of the mold, depressurize the cavity space of the mold and inject liquid matrix resin into the cavity space to impregnate the fiber fabric layer with the matrix resin, and apply internal pressure to the bag-like body Hollow molding in which a fiber reinforced resin layer is formed on the outer periphery of the core by expanding and pressing the hollow molding substrate against the cavity surface of the mold and molding, curing or solidifying the matrix resin impregnated in the fiber fabric layer In a manufacturing method for manufacturing a product, before the bag-like body is inflated, the hollow portion of the core is filled with a filler, and the bag-like body is inflated with the filler interposed between the bag-like body and the core. That It is a symptom.

  According to the method for producing a hollow molded article of the present invention described above, the filler is filled in the hollow portion of the core, and the bag-like body is expanded with the filler interposed between the bag-like body and the core. Therefore, it is possible to transmit the internal pressure of the bag-like body to a complicated shape portion that is difficult to be pressed only by the bag-like body through the filler that enters between the shape portion and the bag-like body. .

  Therefore, the internal pressure received by the core from the bag-like body can be made uniform at each part of the core, and all the parts of the fiber fabric layer can be pressed against the cavity surface with the same pressing force, and the hollow molding substrate is molded into a shape along the cavity surface. can do. Therefore, even if it has a complicated shape, it can be molded without any inconvenience, and a hollow molded product in which the thickness of the matrix resin of the fiber reinforced resin layer is uniform and the outer dimensional accuracy is good can be obtained.

  Further, when the bag-like body is inflated, the bag-like body can be prevented from entering the complicated shape portion of the hollow molded base material, and the bag-like body can be easily taken out from the hollow portion of the hollow molded article after molding. be able to. Therefore, the bag-like body and the filler can be used repeatedly. Moreover, it is not necessary to prepare a bag-like body corresponding to the shape of the hollow molded product, and the bag-like body can have versatility.

  In the above-described method for producing a hollow molded article according to the present invention, the internal pressure of the bag-like body may be higher than the injection pressure of the matrix resin. Thereby, it can prevent that the hollow shaping | molding base material pressed on the cavity surface with the internal pressure of the bag-like body is pushed back by the injection pressure of the matrix resin and separated from the cavity surface.

  Alternatively, the matrix resin may be cured or solidified in an expanded state by applying internal pressure to the bag-like body. Accordingly, it is possible to prevent the hollow resin from shrinking or deforming due to the shrinkage pressure when the matrix resin is cured or solidified.

  As a preferred embodiment of the method for producing a hollow molded article according to the present invention, after forming a hollow molded substrate to produce a hollow molded article, the filler is discharged from the hollow portion of the hollow molded article to form a bag-like body It is characterized by taking out. According to this, by discharging the filler, it is possible to form a gap between the hollow portion of the hollow molded product and the bag-shaped body, and when the bag-shaped body is taken out from the hollow portion of the hollow molded product, it is caught. And can be easily removed.

  Further, as a preferred embodiment of the method for producing a hollow molded article according to the present invention, the filler is a granular material. According to this, when discharging from the hollow part of a hollow molded product, it can discharge quickly and easily. In addition, it is easier to handle than liquids and the like.

  An apparatus for producing a hollow molded article according to the present invention forms a hollow molded substrate having a core having a hollow portion and a fiber woven fabric layer formed on the outer periphery of the core, and cures or cures the matrix resin impregnated in the fiber woven fabric layer. In a manufacturing device that manufactures a hollow molded product that is solidified and has a fiber reinforced resin layer formed on the outer periphery of the core, it has a cavity surface that corresponds to the outer shape of the hollow molded product, and accommodates the hollow molded substrate during mold clamping A mold configured to form a possible cavity space, a decompression means for decompressing the cavity space of the mold, a resin injection means for injecting a matrix resin into the cavity space decompressed by the decompression means, A hollow molded substrate having a bag-like body inserted into the hollow portion and inflated by supplying a pressurized fluid; and a filler filled in the hollow portion and interposed between the bag-like body and the core. Completion Placed in the cavity of the mold, the bag-like body is inserted into the hollow portion, and the filling material is filled between the bag-like body and the core, and a pressurized fluid is supplied to the bag-like body to expand it. The hollow molding substrate is pressed against the cavity surface through a filler and molded.

  Unlike the prior art, the hollow molded article manufacturing apparatus of the present invention is filled with a filler in the hollow portion of the core and interposed between the bag-like body of the pressurizing means and the core. Therefore, when the bag-like body is inflated, the complicated shape portion that is difficult to be pressed only by the bag-like body is passed through the filler that has entered between the shape portion and the bag-like body. The internal pressure of the cylindrical body can be transmitted.

  Accordingly, the internal pressure received by the core from the bag-like body can be made uniform at each part of the hollow molded base material, and all the parts of the hollow molded base material can be pressed against the cavity surface with a uniform pressing force. Can be molded into different shapes. Therefore, even if it has a complicated shape, it can be molded without any inconvenience, and a hollow molded product in which the thickness of the matrix resin of the fiber reinforced resin layer is uniform and the outer dimensional accuracy is good can be obtained.

  Further, when the bag-like body is inflated, the bag-like body can be prevented from entering the complicated shape portion of the hollow molded base material, and the bag-like body can be easily taken out from the hollow portion of the hollow molded article after molding. be able to. Therefore, the bag-like body and the filler can be used repeatedly. Moreover, it is not necessary to prepare a bag-like body corresponding to the shape of the hollow molded product, and the bag-like body can have versatility.

  According to the method and apparatus for producing a hollow molded article of the present invention, even a complicated shape portion that is difficult to be pressed only by a bag-like body is provided with a filler that enters between the shape portion and the bag-like body. Thus, the internal pressure of the bag-like body can be transmitted.

  Accordingly, the internal pressure received by the hollow molded base material from the bag-like body can be made uniform at each part of the hollow molded base material, and all the parts of the hollow molded base material can be pressed against the cavity surface with a uniform pressing force. It can be formed into a shape along the surface. Therefore, even if it has a complicated shape, it can be molded without any inconvenience, and a hollow molded product with good external dimension accuracy can be obtained. Further, the bag-like body can be prevented from entering a complicated shape portion, and can be easily taken out together with the filler from the hollow portion of the hollow molded product after molding.

  Next, embodiments of the present invention will be described below with reference to the drawings.

  An apparatus 10 for manufacturing a hollow molded article in the present embodiment forms a hollow molded substrate 1 composed of a core 2 and a fiber fabric layer 3 using an RTM molding method, and a fiber reinforced resin layer is formed on the outer periphery of the core 2. The formed hollow molded product is manufactured. The RTM molding method in the present embodiment is a kind of internal pressure molding method, in which the hollow molding substrate 1 in which the internal pressure hose 22 is inserted into the hollow portion 2b of the core 2 is disposed in the cavity space of the molding die 11. The cavity space is depressurized, a liquid matrix resin is injected into the cavity space of the mold 11 and impregnated in the fiber fabric layer 3 of the hollow molding substrate 1, and a pressurized fluid is supplied to the internal pressure hose 22. It is defined as a molding method in which the hollow molding substrate 1 is pressed against the cavity surfaces 12a and 13a of the molding die 11 and molded.

  As shown in FIG. 1, the mold 11 includes an upper mold 12 and a lower mold 13 that are relatively close to each other. The upper mold 12 and the lower mold 13 have cavity surfaces corresponding to the outer shape of the hollow molded product. 12 a and 13 a are formed to face each other, and a predetermined cavity space is formed by clamping the mold 11.

  The mold 11 is connected to a vacuum pump (not shown) to depressurize the cavity space of the mold 11 and heat from the resin tank (not shown) into the cavity space of the mold 11. An injection passage 16 for injecting a curable matrix resin, and a pressurized air supply passage 17 for supplying pressurized air, which is a pressurized fluid, to a pressurizing means 21 to be described later from a pressure pump (not shown) Is provided. The pressurized air supply passage 17 communicates with a pressurizing chamber 18 formed between the upper mold 12 and the lower mold 13 by clamping the mold 11. The evacuation passage 15 also serves as a resin discharge passage for discharging excess matrix resin in the cavity space when the matrix resin is injected into the cavity space.

  The hollow molding substrate 1 is placed on the cavity surface 13a of the lower mold 13 and is accommodated in the cavity space of the molding mold 11 by clamping (see FIG. 2). The hollow molded substrate 1 includes a core 2 and a fiber fabric layer 3 formed by being wound around the outer periphery of the core 2. The core 2 is made of a resin material such as ABS resin, and has a thin hollow shape that can be elastically deformed and expanded when the internal pressure hose 22 of the pressurizing means 21 is expanded and an internal pressure is applied. is doing.

  The core 2 has a shape approximate to a hollow molded product to be manufactured, and includes a complicated shape portion having a large difference in cross-sectional shape. In this embodiment, the core 2 extends in the longitudinal direction shown in the left-right direction in FIGS. 1 and 2, and an opening 2 a that communicates between the hollow portion 2 b of the core 2 and the outside at one end thereof. Is formed.

  The fiber fabric layer 3 is formed by weaving reinforcing fibers such as carbon fibers and glass fibers, and is wound around the core 2 by a brader machine (not shown) to cover the entire outer periphery of the core 2. .

  The hollow portion 2b of the core 2 is filled with pellets 14 which are granular materials as a filler. The pellet 14 is interposed between the core 2 and the internal pressure hose 22 of the pressurizing means 21 in the hollow portion 2b of the core 2 without any gap. When the internal pressure hose 22 is expanded, the internal pressure hose is passed through the pellet 14. The internal pressure of 22 is transmitted to the core 2, the core 2 is expanded, and the fiber fabric layer 3 can be pressed against the cavity surfaces 12a and 13a.

  The pellet 14 is made of a lightweight granule, and in the present embodiment, a pellet formed of a nylon resin having a particle size of about 1 millimeter is used. The hollow portion 2 b of the core 2 is filled with a quantity of pellets 14 that fills the gap between the internal pressure hose 22. In the present embodiment, pellets that are granules are described as an example of the filler. However, the filler is not limited to solids such as granules, but a liquid such as oil or water, or a gel-like body. But you can.

  A pressurizing means 21 is attached to the hollow molded substrate 1. As shown in FIG. 3, the pressurizing means 21 includes an internal pressure hose 22 that is a bag-like body that expands by supplying pressurized air, an air tube 23 that supplies pressurized air to the internal pressure hose 22, and an air tube 23. It has a closing plug 24 that is inserted and closes the opening 2 a of the core 2.

  The internal pressure hose 22 is made of a highly elastic synthetic resin such as silicone rubber, has a thin cylindrical shape made of a soft sheet-like film, and its tip is constrained by a string-like body and sealed. The base end portion is a sealed bag-like body fixed to the hose fixture 25, and the inside and outside of the internal pressure hose 22 are hermetically isolated.

  The air tube 23 is formed of a synthetic resin such as nylon, has an outer diameter cylindrical shape that can be inserted into the internal pressure hose 22, and is inserted into the hollow portion 2 b from the opening 2 a of the core 2. It can be pushed and moved in the direction and has a degree of flexibility that can be deformed along the shape of the core 2.

  The air tube 23 passes through the through hole 25 a of the hose fixture 25 and is inserted into the internal pressure hose 22, and the distal end extends to the vicinity of the distal end of the internal pressure hose 22. The air tube 23 is provided with a plurality of perforations 23a so as to be positioned at predetermined intervals in the longitudinal direction inside the internal pressure hose 22, and pressurized air supplied into the air tubes 23 is supplied to the perforations 23a. To the inside of the internal pressure hose 22. The internal pressure hose 22 is inserted into the hollow portion 2b of the core 2 with the air tube 23 inserted therethrough, and is disposed so as to extend in the longitudinal direction within the hollow portion 2b.

  As shown in FIG. 1, the closing plug 24 closes the opening 2 a of the core 2 in a state where the internal pressure hose 22 is inserted into the hollow portion 2 b of the core 2 and the pellet 14 is filled in the hollow portion 2 b of the core 2. . As shown in FIGS. 4 and 5, the blocking plug 24 is inserted into the plug 31 that is inserted into the opening 2 a of the core 2, a fixing plate 32 that fixes the plug 31 to the lower mold 13, and the blocking plug 24. A tube fixture 33 for fixing the air tube 23 is provided.

  The plug body 31 has a block shape that is large enough to close the opening 2a when fitted into the opening 2a of the core 2. In the present embodiment, the plug 31 has a rectangular shape that matches the shape of the opening 2a. None, it is formed in a tapered shape that gradually narrows as it moves to the tip side in order to facilitate the fitting operation.

  An attachment screw 34 for removably attaching the fixing plate 32 is projected from the base end portion of the plug body 31. The plug 31 is attached to the fixed plate 32 by inserting a gasket G between the fixed plate 32 and inserting the mounting screw 34 into the insertion hole 32 a of the fixed plate 32 and tightening the mounting nut 35.

  The plug body 31 is provided with a through hole 31a (see FIG. 3) through which the air tube 23 is inserted. The through hole 31a passes through the center of the plug body 31, and one end opens at the tip of the plug body 31, and the other end opens at the top of the mounting screw 34 (see FIG. 5). The air tube 23 can be inserted into the through hole 31 a from the distal end side of the plug 31 and protruded from the top of the mounting screw 34.

  The tube fixture 33 fixes the air tube 23 to the mounting screw 34 by fitting an annular seal member 33a to the air tube 23 protruding from the top of the mounting screw 34 and tightening a fastening nut 33b. The space between the tube 23 and the through hole 31a is sealed. The air tube 23 is fixed in a state protruding from the tube fixture 33 by a predetermined length, and the open end 23 b of the air tube 23 is disposed in the pressurizing chamber 18 when the mold 11 is clamped.

  The closing plug 24 is formed by inserting the plug 31 into the opening 2a of the core 2 with the internal pressure hose 22 inserted into the hollow 2b of the core 2 and the pellet 14 being filled in the hollow 2b. 23 is projected from the mounting screw 34. Then, the fixing plate 32 is covered, the mounting screw 34 is inserted into the insertion hole 32 a of the fixing plate 32, the mounting nut 35 is tightened, and the fixing plate 32 is attached to the plug body 31. Then, the fixing plate 32 is fixed to the lower mold 13 by inserting the fixing bolt 36 through the fixing hole 32 b of the fixing plate 32 and screwing into the screw hole (not shown) screwed to the lower mold 13. Further, the air tube 23 is fixed by the tube fixing tool 33.

  The blocking plug 24 can block the opening 2a of the core 2 and prevent the pellet 14 in the hollow portion 2b from leaking outside. Further, the space between the hollow portion 2b of the core 2 and the cavity space portion of the mold 11 can be sealed, and the matrix resin injected into the cavity space portion can be prevented from entering the hollow portion 2b of the core 2.

  Next, a method for manufacturing a hollow molded product using the hollow molded product manufacturing apparatus 10 having the above configuration will be described.

  First, the hollow molding substrate 1 is placed on the cavity surface 13a of the lower mold 13, the pellet 14 is filled in the hollow portion 2b of the core 2, and the pressurizing means 21 is mounted (see FIG. 1). The mold 11 is clamped, and the hollow molded substrate 1 is disposed in the cavity space of the mold 11 (see FIG. 2). Then, the mold 11 is adjusted to a preset thermosetting temperature, and then the cavity space is evacuated through the evacuation passage 15 by a vacuum pump to reduce the pressure to a predetermined degree of vacuum.

  Then, injection of matrix resin from the resin tank through the resin injection passage 16 into the cavity space of the mold 11 is started, and supply of pressurized air to the pressurizing chamber 18 through the pressurized air supply passage 17 is started by a pressure pump. To do.

  The injection pressure of the matrix resin and the pressure of the pressurized air are increased at substantially the same speed, and are maintained at a preset pressure for a certain period of time. Further, the injection pressure of the matrix resin and the pressure of the pressurized air are set to be lower in the matrix resin than in the pressurized air.

  The matrix resin injected into the cavity space of the mold 11 is impregnated in the fiber fabric layer 3 of the hollow molding substrate 1. The pressurized air supplied to the pressurizing chamber 18 enters the air tube 23 from the open end 23 b of the air tube 23 of the pressurizing means 21 that opens in the pressurizing chamber 18, and passes through the air tube 23. Then, it flows into the internal pressure hose 22 from the perforation 23a, and the internal pressure hose 22 is expanded.

  By the expansion of the internal pressure hose 22, the pellet 14 is pushed and moved in the direction in which the core 2 is expanded, and the internal pressure of the internal pressure hose 22 is transmitted to the core 2 through the pellet 14. Accordingly, the core 2 is expanded, and the fiber fabric layer 3 wound around the core 2 is pressed against the cavity surfaces 12a and 13a.

  Since the pellet 14 is interposed between the internal pressure hose 22 and the complicated shape portion of the core 2 that is difficult to be pressed only by the internal pressure hose 22, the pellet 14 is applied when the internal pressure hose 22 is expanded. The internal pressure of the internal pressure hose 22 can be transmitted and expanded even to complicated shapes.

  Accordingly, the internal pressure received by the core 2 from the internal pressure hose 22 can be made uniform at each part of the core 2, and all the parts of the fiber fabric layer 3 can be pressed against the cavity surfaces 12 a and 13 a with a uniform pressing force. It can be formed into a shape along the surfaces 12a and 13a.

  Further, since the internal pressure of the internal pressure hose 22 is set to be higher than the injection pressure of the matrix resin, the excess matrix resin that is not impregnated in the fiber fabric layer 3 among the matrix resin filled in the cavity space is removed from the cavity. It can be extruded from the space and discharged from the vacuuming passage 15 of the mold 11 to the outside. Accordingly, the collapse of the core 2 due to the injection pressure of the matrix resin is prevented, and the thickness of the matrix resin can be made uniform and appropriate.

  The matrix resin impregnated in the fiber fabric layer 3 receives heat from the mold 11 and starts to cure. In the hollow molded substrate 1, the matrix resin is completely cured in a state where the internal pressure hose 22 is expanded and molded into a desired shape. Therefore, the core 2 can be prevented from collapsing due to the curing shrinkage pressure of the matrix resin, and a hollow molded product with good external dimensional accuracy free from resin sink and deformation can be obtained.

  The hollow molded product is taken out by opening the mold 11. Then, the pellets 14 remaining in the hollow portion 2 b of the core 2 are discharged to the outside from the opening 2 b, and a gap is formed between the internal pressure hose 22 and the core 2. Therefore, the internal pressure hose 22 can be easily and quickly removed from the hollow portion 2b of the core 2 without being caught by a complicated shape portion of the core 2.

  By the above method, a hollow molded article in which a fiber reinforced resin layer is formed on the outer periphery of the core 2 can be manufactured. The above manufacturing method may be performed automatically by a control means (not shown), or an operator may perform a part of the work such as the mounting work of the hollow molded substrate 1. .

  According to the hollow molded article manufacturing apparatus 10 described above, the internal pressure of the internal pressure hose 22 can be transmitted via the pellet 14 to the complicated shape portion of the core 2 that is difficult to be pressed only by the internal pressure hose 22. Therefore, the internal pressure received by the core 2 from the internal pressure hose 22 can be made uniform at each part of the core 2, and all the parts of the fiber fabric layer 3 can be pressed against the cavity surfaces 12 a and 13 a with a uniform pressing force.

  Therefore, the hollow molded substrate 1 can be molded into a complicated shape along the cavity surfaces 12a and 13a, and a hollow molded product with good external dimension accuracy can be obtained. Moreover, when the internal pressure hose 22 is expanded, the internal pressure hose 22 can be prevented from entering a complicated shape portion of the core 2, and the internal pressure hose 22 can be easily and quickly taken out after molding. And the internal pressure hose 22 and the pellet 14 can be used repeatedly, and cost can be reduced. Moreover, it is not necessary to prepare the internal pressure hose 22 having a shape corresponding to the shape of the hollow molded product, and the internal pressure hose 22 can have versatility.

  Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, the case of the hollow molded product manufacturing apparatus 10 using the RTM molding method in which the fiber fabric layer 3 is impregnated with the matrix resin in the molding die 11 has been described as an example. Is also fully applicable.

  The present invention inserts the bag-like body 22 into the hollow portion 2a of the hollow molded base material 1 and fills the granular body 14 with the expansion of the internal pressure hose 22 to expand the hollow molded base material 1 through the granular body 14, What is necessary is just to press and shape the hollow shaping | molding base material 1 to the cavity surfaces 12a and 13a of the shaping | molding die 11, For example, it replaces with the fiber fabric layer 3 of the hollow shaping | molding base material 1 in the said embodiment, and is a reinforced fiber. Alternatively, a prepreg impregnated with a matrix resin in advance may be used.

  In the above-described embodiment, the case where the matrix resin is thermosetting has been described as an example. However, the matrix resin may be thermoplastic. When the matrix resin is thermoplastic, a process is performed in which the hollow molded substrate is molded in a heated state and cooled and solidified after molding.

Sectional drawing which shows schematically the structure of the manufacturing apparatus of the hollow molded article concerning embodiment of this invention. Sectional drawing which shows the state which clamped the apparatus of FIG. Sectional drawing which shows the structure of a pressurization means roughly. The perspective view which expands and shows the principal part of a pressurizing means. The exploded perspective view of a pressurizing means.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hollow molding base material 2 Core 2b Hollow part 3 Textile fabric layer 11 Mold 12a, 13a Cavity surface 14 Pellet (granular body)
22 Internal pressure hose (bag-like body)

Claims (7)

In a state where the hollow molding base material in which the bag-like body is inserted into the hollow portion is arranged in the cavity space portion of the molding die, the bag-like body is expanded by applying an internal pressure, and the hollow molding base material is expanded into the cavity of the molding die. In a method for producing a hollow molded article using an internal pressure molding method for molding by pressing on a surface,
Before inflating the bag-like body, filling the hollow portion of the hollow molded base material with a filler,
A method for producing a hollow molded article, wherein the bag-shaped body is expanded in a state where the filler is interposed between the bag-shaped body and the hollow molded substrate. A hollow molding substrate having a core having a hollow portion and a fiber fabric layer formed on the outer periphery of the core is disposed in the cavity space portion of the molding die in a state where a bag-like body is inserted into the hollow portion, The cavity space of the mold is depressurized and a liquid matrix resin is injected into the cavity space to impregnate the fiber woven fabric layer with the matrix resin, and the bag-like body is expanded by applying internal pressure to the hollow space. A hollow molded product in which a molding substrate is pressed against the cavity surface of the mold and molded, and the matrix resin impregnated in the fiber fabric layer is cured or solidified to form a fiber reinforced resin layer on the outer periphery of the core In the manufacturing method for manufacturing
Before inflating the bag-like body, the hollow portion of the core is filled with a filler,
A method for producing a hollow molded article, wherein the bag-like body is expanded in a state where the filler is interposed between the bag-like body and the core.   The method for producing a hollow molded article according to claim 2, wherein an internal pressure of the bag-like body is higher than an injection pressure of the matrix resin.   The method for producing a hollow molded article according to claim 2 or 3, wherein the matrix resin is cured or solidified in an expanded state by applying an internal pressure to the bag-like body.   The hollow molding according to any one of claims 1 to 4, wherein after the hollow molded article is manufactured, the bag-like body is taken out by discharging the filler from a hollow portion of the hollow molded article. Product manufacturing method.   The said filler is a granular body, The manufacturing method of the hollow molded article of any one of Claims 1-5 characterized by the above-mentioned. A hollow molded substrate having a core having a hollow portion and a fiber woven fabric layer formed on the outer periphery of the core is molded, and a matrix resin impregnated in the fiber woven fabric layer is cured or solidified to form an outer periphery of the core. In a manufacturing apparatus for manufacturing a hollow molded article in which a fiber reinforced resin layer is formed,
A mold having a cavity surface corresponding to the outer shape of the hollow molded article and configured to form a cavity space capable of accommodating the hollow molded base material during mold clamping;
Pressure reducing means for reducing the pressure in the cavity space of the mold,
Resin injecting means for injecting matrix resin into the cavity space depressurized by the depressurizing means;
A bag-like body inserted into the hollow portion and inflated by the supply of pressurized fluid;
A filler filled in the hollow portion and interposed between the bag-like body and the core;
In the state where the hollow molding substrate is disposed in the cavity space portion of the molding die, the bag-like body is inserted into the hollow portion, and the filler is filled between the bag-like body and the core, An apparatus for manufacturing a hollow molded article, wherein the pressurized fluid is supplied to the bag-like body to expand and the hollow molding substrate is pressed against the cavity surface through the filler.

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