JP2000238141A - Method and apparatus for molding composite resin product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently manufacture a cylindrical product having stable dimensional accuracy by mass-producing without necessity of an external pressure applying unit at molding. SOLUTION: The apparatus 10 for molding a composite resin product comprises a pressure medium 12 integrally combined with a degassing porous filter 11 and a thermal expansion material 12, a preform 14, and a split mold 15 for arranging the preform 14 in the mold to impregnate thermosetting resin or thermoplastic resin containing volatile component. The apparatus 10 is an embodiment in which, in the case of molding a composite resin product made of a hollow cylinder, an outer surface of the preform 14 is brought into close contact with the mold 15 to be molded as an external size reference. Or, in the case of molding with a hollow part of the preform 14 as a reference of an inner size reference, a metal mandrel to be engaged with the hollow part of the preform 14 is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for molding a composite resin product, and more particularly, to a method for efficiently producing a cylindrical product having a stable dimensional accuracy without requiring an external pressure applying device at the time of molding. The present invention relates to a method and an apparatus for molding a composite resin product which can be manufactured at low cost.

[0002]

2. Description of the Related Art Conventionally, as a method of forming a composite resin product in which a reinforcing fiber base material is impregnated with a matrix resin and formed into a predetermined shape, a molding method using a core having thermal expansion properties (Japanese Patent Laid-Open No. 5-131555). And a molding method in which a solvent and a reaction product gas are discharged out of a mold and cured using a porous filter (Japanese Patent Application Laid-Open No. 9-117964).

In the former molding method using a core having thermal expansion properties, a thermoplastic resin is used as a matrix between a thermal expansion core and a pipe-shaped outer die arranged outside the core. The prepreg is interposed, and then the prepreg and the core are heated to a temperature equal to or higher than the plasticization temperature of the thermoplastic resin to expand the core, thereby forming a fiber-reinforced resin hollow body between the core and the outer mold. Is the way.

[0004] In the latter molding method using a porous filter, a reinforcing fiber base material is placed in a cavity of one mold, and then the other mold is fitted therein. Is transported under reduced pressure or pressure to impregnate the reinforcing fiber base material with the matrix resin, and the low molecular weight substances generated during the impregnation are removed out of the system while being selected by a porous filter to form a composite material. Things.

[0005]

By the way, when a composite product such as a tubular part is manufactured by using a resin containing a volatile component (for example, a polyimide resin), only the above-mentioned thermally expandable core is used. In the case of using a method, gas outgassing is not possible, so low molecular weight substances such as solvent, water and alcohol remain in the mold and mix into the matrix resin to generate voids, which adversely affects the quality of composite molded products There is a problem to say that.

In the method using only a porous filter, the pressure loss at the time of pressure transmission becomes large, and an external pressure applying device is required at the time of molding, so that mass production becomes impossible and the cost increases. is there.

Further, as shown in FIG. 7, the inside and outside of the cylindrical molded body 2 are sandwiched in a mold 1 by a porous filter 3 for deaeration and a thermal expansion body 4 for applying pressure composed of a thermal expansion core. In the method of simply combining the porous filter 3 and the thermal expansion body 4 for applying pressure, the inner and outer surfaces of the molded body 2 are in contact with the elastic material. There is a problem that quality such as accuracy and appearance deteriorates.

An object of the present invention is to provide a composite resin product which does not require an external pressure applying device at the time of molding, enables mass production, and enables efficient production of a cylindrical product having stable dimensional accuracy at a low cost. And a molding method therefor.

[0009]

In order to achieve the above object, the present invention provides a first method of molding a composite resin product, which comprises:
A pressure medium integrally combining a degassing porous filter and a thermal expansion body is inserted into a hollow portion of a preform made of a reinforcing fiber base formed in a hollow cylindrical shape in a state of being in close contact with the preform, and the preform is inserted. After being placed in the mold, a thermosetting resin or a thermoplastic resin containing a volatile component is injected into the mold to impregnate the preform, and then heated in a state in which the mold is sealed. The gist of the invention is to expand the pressure medium, press the outer peripheral surface of the preform against the inner surface of the mold, and cure the preform.

[0010] In a second method for molding the composite resin product of the present invention, a mandrel is inserted into a hollow portion of a preform made of a reinforcing fiber base material formed in a hollow cylindrical shape, and the mandrel is inserted into the outer peripheral surface of the preform. A cylindrical pressure medium in which a porous filter for deaeration and a thermal expansion body are integrally combined is fitted, and the preform and the pressure medium thus configured are arranged in a mold to contain volatile components. Impregnating the preform with a thermosetting resin or a thermoplastic resin, and then heating the mold in a sealed state, thereby expanding the pressure medium and pressing the inner wall surface of the preform against the mandrel surface and curing. The gist of the present invention is to manufacture by making it.

Further, as a third molding method of the composite resin product of the present invention, a mandrel is inserted into a hollow portion of a preform made of a reinforcing fiber base formed in a hollow cylindrical shape, and the mandrel is inserted into an outer peripheral surface of the preform. A cylindrical pressure medium in which a porous filter for deaeration and a thermal expansion body are integrally combined is fitted, and a thermosetting resin or a thermoplastic resin containing volatile matter is impregnated into the preform, and then heated. The gist of the invention is to expand the pressure medium, press the inner wall surface of the preform against the mandrel surface, and cure the preform.

Further, as a molding apparatus for a composite resin product of the present invention, the molding apparatus includes a pressure medium in which a porous filter for deaeration and a thermal expansion body are integrally combined, and a reinforcing fiber formed in a hollow cylindrical shape. The gist consists of a preform made of a base material and a mold provided with the preform and impregnated with a thermosetting resin or a thermoplastic resin containing a volatile component. The present invention is configured as described above, and when molding a cylindrical part or the like using a thermosetting resin or a thermoplastic resin containing a volatile component, the degassing porous filter and the thermal expansion body are integrally formed. Using a combined pressure medium, a cylindrical preform (molded body) is disposed between the pressure medium and a mold having a rigid inner wall surface, and the pressure medium is expanded to expand the outer peripheral surface of the preform. Alternatively, the dimensional accuracy of the outer surface or the inner surface of the molded article can be increased by pressing the inner wall surface against the inner wall surface of the mold or the surface of the mandrel and heat-curing.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an exploded perspective view of a molding apparatus for molding the composite resin product of the present invention. This molding apparatus 10 has a pressure in which a porous filter 11 for deaeration and a thermal expansion body 12 are integrally combined. Preform 1 comprising medium 13 and hollow fiber-shaped reinforcing fiber base material
4 and a two-part mold 15 in which the preform 14 is disposed in a mold and impregnated with a thermosetting resin or a thermoplastic resin containing volatile components.

The above-mentioned molding apparatus 10 is used to mold a preform 1 when molding a composite resin product comprising a hollow cylindrical body.
4 is an embodiment in which an outer dimension formed by bringing the outer surface of the preform 4 into close contact with a rigid mold 15 is used as an external dimension reference for finishing with high accuracy, and an internal dimension reference based on a hollow portion of the preform 14 is used. Uses a mandrel 16 made of metal, resin or the like that fits into the hollow portion of the preform 14.

The thermal expansion member 12 constituting the pressure medium 13
Uses a Teflon resin having a linear expansion coefficient of 1.0 × 10 ^-5 ° C ^-1 or more. The deaeration porous filter 11 constituting the pressure medium is made of polytetrafluoroethylene resin, sintered metal, graphite or ceramics. Is preferably one selected from the group consisting of
%, Preferably in the range of 35% to 15%.

If the porosity is 40% or more, the flow of the resin is large, and the porous filter does not function. If the porosity is 10% or less, it becomes difficult to remove low molecular weight substances and the like.

Next, a molding method for molding the composite resin product of the present invention will be described. FIG. 1 is an exploded perspective view showing a first embodiment of a molding method for molding a composite resin product. The first embodiment is an embodiment based on the outer dimensions of a composite resin product, and firstly, a hollow resin is used. A mold 1 into which a preform 14 made of a reinforcing fiber base material such as a tubular woven fabric, a unidirectional material in which fibers are aligned, and a blind unidirectional material is fitted.
Prepare 5

In the hollow portion 14a of the preform 14 formed of the reinforcing fiber base formed in the hollow cylindrical shape, the deaeration porous filter 11 having the above-described structure and the thermal expansion body 12 are integrated. The precombined pressure medium 13 is inserted in a state of being in close contact with the preform 14, and the preform 14 is placed in the mold 15.

Thereafter, a thermosetting resin or a thermoplastic resin (not shown) containing a volatile component is injected into the mold 15 to impregnate the preform 14, and then the mold 15 is sealed, for example, as shown in FIG. By placing in an oven that is not heated and heating, unnecessary volatile components are selectively discharged out of the mold through the porous filter 11 for deaeration.
The pressure medium 13 is expanded and the outer peripheral surface of the preform 14 is pressed against the inner surface of the mold 15 and cured to produce a hollow cylindrical composite resin product.

FIG. 2 shows the structure of the pressure medium 13. The configuration of the deaeration porous filter 11 and the thermal expansion body 12 is not limited to the embodiment of FIG.
It is good also as composition which arranged porous filter 11 for deaeration at both ends or one end of thermal expansion object 12.

FIGS. 3 to 5 are exploded views of a molding method according to a second embodiment of the present invention. This embodiment is an embodiment based on the internal dimensions of a composite resin product. A mold 15 to which a pressure medium 13 formed in a hollow cylindrical shape is fitted and a metal or resin mandrel 16 to be fitted into the hollow portion 14a of the preform 14 are prepared.

Then, a mandrel 16 is inserted into the hollow portion 14a of the preform 14 made of a reinforcing fiber base formed in a hollow cylindrical shape, and the deaeration porous filter 11 and the thermal expansion are formed on the outer peripheral surface of the preform 14. After the cylindrical pressure medium 13 integrally combined with the body 12 is fitted and the preform 14 and the pressure medium 13 configured as described above are arranged in the mold 15, the thermosetting resin containing volatile components is formed. The preform 14 is impregnated with a resin or a thermoplastic resin, and then placed in an oven with the mold 15 sealed, and heated to remove unnecessary volatile components from the porous filter 1 for deaeration.
While selectively ejecting the pressure medium 13 through the mold 1, the pressure medium 13 is expanded to press the inner wall surface of the preform 14 against the surface of the mandrel 16 and harden to form a composite resin product comprising a hollow cylindrical body. I do.

FIG. 4 shows a case where the end portion of the deaeration porous filter 11 constituting the pressure medium 13 is formed longer than the thermal expansion body 12 in the second embodiment, and FIG. 13 is constituted only by the porous filter 11 for deaeration.

FIG. 6 is an exploded perspective view of a molding method according to a third embodiment of the present invention. This embodiment is an embodiment based on the outer dimensions of a hollow composite resin product. However, while the present invention is directed to molding a hollow cylindrical composite resin product, this embodiment is a case of molding a composite resin product having a square cross section.

That is, as shown in FIG. 6, a mold 15A to be fitted with a preform 14A made of a reinforcing fiber base formed in a hollow square shape is prepared. And preform 14A
Is inserted into the hollow portion 14a in a state in which a pressure medium 13A in which a porous deaeration porous filter 11A formed in a square cross section and a thermal expansion body 12A are integrally combined is brought into close contact with each other,
The preform 14A is placed in a mold 15A.

Thereafter, a thermosetting resin or a thermoplastic resin (not shown) containing a volatile component is injected into the mold 15A to impregnate the preform 14A.
A is placed in an oven (not shown) in a sealed state and heated to expand the pressure medium 13A while selectively discharging unnecessary volatile components out of the mold through the degassing porous filter 11. The outer peripheral surface of the preform 14A is pressed against the inner surface of the mold 15A and cured to produce a hollow rectangular composite resin product.

When a tubular part or the like is formed using a thermosetting resin or a thermoplastic resin containing a volatile component by the above-described method, the degassing porous filter 11 and the thermal expansion body 12 are integrated. A cylindrical preform 14 (molded body) is disposed between the pressure medium 13 and a mold 15 having a rigid inner wall surface, and the pressure medium 13 is expanded. Then, the outer peripheral surface or the inner wall surface of the preform 14 is pressed against the inner wall surface of the mold 15 or the surface of the mandrel, and is cured by heating, so that the dimensional accuracy of the outer surface or the inner surface of the molded body can be improved.

[0028]

The present invention is constructed as described above, and has the following excellent effects. . An external pressure applying device is not required at the time of molding, and mass production is possible, and therefore, cost reduction can be achieved. . By using a resin containing a volatile component, molding of a tubular part or the like becomes easy. . By designing the shapes of the mold and the pressure medium, it is possible to mold a material having a complicated shape. . A cylindrical product with stable dimensional accuracy can be manufactured efficiently. . Since the configuration of the entire apparatus is simple, it can be manufactured at low cost and maintenance is easy.

[Brief description of the drawings]

FIG. 1 is an exploded configuration diagram of a molding apparatus for performing a molding method according to a first embodiment of the present invention, and an explanatory diagram of the molding method.

FIG. 2 is a perspective view of a preform usable in the first embodiment and a pressure medium.

FIG. 3 is an exploded configuration diagram of a molding apparatus for performing a molding method according to a second embodiment of the present invention, and an explanatory diagram of the molding method.

FIG. 4 is a perspective view of a preform in which a mandrel usable in the second embodiment is inserted, a deaeration porous filter and a thermal expansion body that constitute a pressure medium.

FIG. 5 is a perspective view of a preform in which a mandrel usable in the second embodiment is inserted, and a porous filter for deaeration constituting a pressure medium.

FIG. 6 is an exploded configuration diagram of a molding apparatus for performing a molding method according to a third embodiment of the present invention, and an explanatory diagram of the molding method.

FIG. 7 is a sectional view of a conventional molding apparatus.

[Description of Signs] 10 Molding device 11 Porous filter for deaeration 12 Thermal expansion body 13 Pressure medium 14 Preform 15 Mold 16 Metal mandrel 14a Hollow part of preform

Continued on the front page (72) Inventor Hiroshi Mizuno 10 Oe-cho, Minato-ku, Nagoya-shi, Aichi Mitsubishi Heavy Industries, Ltd. Nagoya Aerospace Systems Works (72) Inventor Yoshihiro Soeda 2-1 Oiwake, Hiratsuka-shi, Kanagawa Prefecture Yokohama Rubber Co., Ltd. (72) Inventor Tomohiro Ito 2-1 Oiwake, Hiratsuka-shi, Kanagawa Prefecture Yokohama Rubber Co., Ltd. F-term (reference) 4F205 AD16 AG08 AJ02 AJ03 AJ06 AJ10 HA06 HA24 HA33 HA34 HA35 HA44 HA47 HB01 HK04 HK05 HK14 HK32 HM02

Claims (7)

[Claims] 1. A pressure medium in which a degassing porous filter and a thermal expansion body are integrally combined is inserted into a hollow portion of a preform made of a reinforcing fiber base material formed in a hollow cylindrical shape in a state of being in close contact with each other. After placing the preform in the mold, a thermosetting resin or a thermoplastic resin containing volatile components is injected into the mold to impregnate the preform,
A method of molding a composite resin product, wherein the pressure medium is expanded by heating the mold in a sealed state, and the outer peripheral surface of the preform is pressed against the inner surface of the mold and cured. 2. A mandrel is inserted into a hollow portion of a preform made of a reinforcing fiber base material formed in a hollow cylindrical shape, and a deaeration porous filter and a thermal expansion body are integrally formed on an outer peripheral surface of the preform. The combined cylindrical pressure medium is fitted, the preform and the pressure medium thus configured are arranged in a mold, and the preform is impregnated with a thermosetting resin or a thermoplastic resin containing volatile matter. Thereafter, a method of molding a composite resin product is produced by heating the mold in a sealed state, thereby expanding the pressure medium and pressing and hardening the inner wall surface of the preform against the mandrel surface. 3. A mandrel is inserted into a hollow portion of a preform made of a reinforcing fiber base formed in a hollow cylindrical shape, and a porous filter for deaeration and a thermal expansion body are integrally formed on an outer peripheral surface of the preform. The combined cylindrical pressure medium is fitted, and the preform is impregnated with a thermosetting resin or a thermoplastic resin containing a volatile component, and then heated to expand the pressure medium, thereby causing the preform to expand. A method of molding a composite resin product manufactured by pressing and curing a wall surface on a mandrel surface. 4. The method for molding a composite resin product according to claim 1, wherein the thermal expansion member constituting the pressure medium is a Teflon resin having a linear expansion coefficient of 1.0 × 10 ⁻⁵ ° C ⁻¹ or more. . 5. The degassing porous filter constituting the pressure medium is one selected from a polytetrafluoroethylene resin, a sintered metal, graphite and ceramics, and has a porosity of 40% to 40%. The method for molding a composite resin product according to any one of claims 1, 2, 3, and 4, wherein the amount is in the range of 10%. 6. A composite resin product molding apparatus for molding a thermosetting resin or a thermoplastic resin molded article containing a volatile component and capable of applying pressure during molding, the molding apparatus comprising: a degassing porous material; A pressure medium in which a filter and a thermal expansion body are integrally combined, a preform made of a reinforcing fiber base formed in a hollow cylindrical shape, and a preform are arranged, and a thermosetting resin or a thermosetting resin containing volatile components is disposed. An apparatus for molding a composite resin product comprising a mold impregnated with a plastic resin. 7. The composite resin product molding apparatus according to claim 6, wherein a mandrel that fits into a hollow portion of the preform is used when the hollow cylindrical resin product is based on an inner diameter.