JP5352119B2 - Molding core and manufacturing method thereof - Google Patents

Description

The present invention relates to a molding core formed in an elongated shape and a method for manufacturing the same .

As structural members for aircraft, ships, automobiles, etc., those made of fiber reinforced plastics (FRP) are widely used from the viewpoint of weight reduction. As a method for manufacturing such a structural member, for example, as disclosed in Patent Documents 1 and 2, a fiber laminate in which a reinforcing fiber base material is laminated in advance is shaped into a final product shape to form a preform. An RTM method (Resin Transfer Molding method) in which matrix resin is injected into the reforming and cured, or layers in which fibers and resins are laminated alternately are placed in an autoclave, and a predetermined heat is applied under a predetermined pressure. And an autoclave method for curing the resin.
JP 2007-62150 A JP 2007-118598 A

  By the way, in the case of forming a reinforcing hollow rib on the structural member, a rubber molding core formed in an elongated shape is provided in advance when setting the material to the mold before molding, and molding is performed after molding. For example, the molding core is pulled out from the product.

  However, if the length of the molding core is long, it becomes difficult to pull out the molding core from the molded product.

An object of the present invention is to provide a molding core that can prevent resin adhesion during FRP molding, has releasability (non-adhesiveness), and can be easily pulled out from a molded product, and a method for manufacturing the same. .

The present invention is a molding core formed in an elongated shape,
A core body formed of a viscoelastic material made of a crosslinked polymer composition and having a corner portion extending along the length direction ;
Before SL and the surface coating film comprising a fluororesin film which is provided so as core body and is integrally molded butted at the top of the corner of and the core body covers the surface of the core body ,
Ru equipped with.
The present invention is a method of manufacturing a molding core formed in an elongated shape,
The molding core is formed of a viscoelastic material made of a crosslinked polymer composition and has a core body having a corner extending along the length direction, and the core body is integrally molded with the core body. A surface covering film composed of a fluororesin film that covers the surface of the core body and is provided to be abutted at the top of the corner of the core body, and
A first surface coating film is provided so as to cover the bottom and side surfaces of the lower recess of the lower mold constituting the cavity and extend to the upper surface of the lower mold, and an uncrosslinked polymer composition is formed on the first surface coating film of the lower recess Providing a step;
Providing a second surface coating film so as to cover the uncrosslinked polymer composition provided in the lower recess of the lower mold and extend to the upper surface of the lower mold and overlap the first surface coating film;
An upper mold is provided on the lower mold and clamped, and held at a predetermined mold temperature and clamping pressure for a predetermined time to crosslink the uncrosslinked polymer composition to mold a core body, and Adhering the first and second surface coating films to the core body and integrally molding the core body with the first and second surface coating films; and
The upper mold and the lower mold are opened, and a molded body is taken out. From the molded body, the first and second surface coatings between the lower mold and the upper mold are caused by an excess of the uncrosslinked polymer composition. Cut the burrs formed by flowing from the film to the mold matching part, and the burrs formed by flowing the excess of the first and second surface coating films toward the end and flowing to the mold matching part. A step of obtaining a molding core having a corner portion where the surface coating film is abutted at the top; and
including.

According to the present invention, the surface coating film of the fluorine resin film that is core body integrally molded is provided so as to cover the surface of the core body, releasing it is possible to prevent resin deposition during FRP molding (Non-adhesive) and low slip resistance on the surface, so that it can be easily pulled out from the molded product. Thus, it can be repeatedly used for FRP molding.

  Hereinafter, embodiments will be described in detail based on the drawings.

  FIG. 1 shows a molding core 10 according to the present embodiment. The molding core 10 according to the present embodiment is provided in advance in a mold at the time of material setting before molding when manufacturing FRP components such as aircraft, ships, automobiles, etc. by a method such as RTM method or autoclave method. It is used to form a hollow part in the constituent member by being pulled out from the constituent member which is a molded product after molding.

  The molding core 10 is formed in an elongated shape having a rectangular cross section. The molding core 10 is formed with a hollow portion H having a rectangular outer cross-sectional shape extending in the length direction at the center thereof. The molding core 10 may be formed in a straight line shape or may be formed in a bow shape. The molding core 10 has, for example, a length of 0.5 to 15 m, a width of 50 to 150 mm, a height of 20 to 150 mm, and a vertical diameter of the hollow portion H of 10 to 50 mm and a horizontal diameter of 20 mm. ˜100 mm and the wall thickness is generally 2 to 30 mm.

The molding core 10, the core body 11 outer shape constituting a is formed of a material having viscoelastic and consist of a sheet-like fluororesin film so as to cover wrapped surface of the core body 11 The surface covering film 12 is provided integrally with the core body 11, and the fiber reinforcing material 13 is embedded in the core body 11 so as to surround the hollow portion H.

According to the molding core 10, the surface coating film 12 of the fluororesin film that is integrally formed with the core body 11 is provided so as to cover the surface of the core body 11, the resin during FRP molding Adhesion can be prevented and releasability (non-tackiness) is provided, and the slip resistance of the surface is low, so that it can be easily pulled out from the molded product. Thus, it can be repeatedly used for FRP molding.

  Moreover, since the fiber reinforcing material 13 is embed | buried and reinforced along the length direction in the core main body 11, even if it uses repeatedly, pressure resistance and dimensional stability can be maintained.

  Examples of the viscoelastic material forming the core body 11 include a crosslinked polymer composition such as a rubber material or a resin material. The polymer composition is obtained by crosslinking an uncrosslinked polymer composition in which a raw material polymer is blended with a curing agent, a pigment, or the like, by heating and pressing. The molding core 10 has a durometer type A spring-type surface hardness measured according to JIS K6253, for example, 50 to 80, and the uncrosslinked polymer composition is blended and designed so that such surface hardness is realized. ing.

  The polymer composition is preferably a silicone rubber composition from the viewpoint of heat resistance. In this case, examples of the raw material polymer include polydimethyl silicone rubber (MQ), methyl vinyl silicone rubber (VMQ), methyl phenyl silicone rubber (PMQ), and fluorosilicone rubber (FVMQ). Examples of the curing agent include organic peroxides such as alkyl organic peroxides. In addition, the silicone rubber composition may contain a reinforcing agent (silica), a pigment, an internal mold release agent, and the like.

Examples of the fluorine resin film constituting the surface coating film 12, for example, those formed with polytetrafluoroethylene (PTFE), which was formed of tetrafluoroethylene-ethylene copolymer (ETFE), tetrafluoroethylene-per Those formed with a fluoroalkyl vinyl ether copolymer (PFA) and those formed with a tetrafluoroethylene / hexafluoropropylene copolymer (FEP) are mentioned. Of these, a polytetrafluoroethylene (PTFE) is used. Are preferred. Fluororesin film is particularly preferable that the alkali treatment with sodium metal inside the adhesive surface was made.

  The surface covering film 12 is formed in a sheet shape and is provided so as to wrap the core body 11. The presence of wrinkles on the surface of the molding core 10 means that the wrinkles are transferred to the component that is the molded product, and resistance when the molding core 10 is pulled out from the component that is the molded product. This is not preferable. However, since the surface coating film 12 is formed in a sheet shape and is provided so as to wrap the core body 11, the surplus portion of the surface coating film 12 is at the end when the molding core 10 is manufactured. Thus, generation of wrinkles of the surface coating film 12 on the surface of the molding core 10 is suppressed. The surface covering film 12 has a thickness of, for example, 50 to 200 μm.

  Further, the surface covering film 12 is provided so as to be abutted at the top of the corner portion 11 a of the core body 11. As a result, the abutting portion where the surface coating film 12 is discontinuous is not disposed on the flat portion of the component to be molded, and its transfer is prevented. At the time of manufacturing the molding core 10, the core body 11 The surplus of the material forming the core flows out from the abutting portion of the surface coating film 12, thereby forming the core body 11 with less internal distortion.

  Examples of the fiber material constituting the fiber reinforcement 13 include aramid fiber, nylon fiber, polyester fiber, glass fiber, and carbon fiber. The fiber material that constitutes the fiber reinforcement 13 may be composed of a single species or a plurality of species.

  The fiber reinforcing material 13 may be composed of a braid, may be composed of a woven fabric, may be further composed of a knitted fabric, and may be composed of a non-woven fabric. The fiber reinforcing material 13 has a thickness of, for example, 0.1 to 1.0 mm.

  Examples of the braid include, for example, a flat strut braid; a round strut braid; a vertical stripe braid, a cross-jointed braid, a double braid, and a braid lace rugged hammer strut.

  The yarn constituting the braided fiber reinforcing material 13 is not particularly limited, and may be a yarn composed of only one kind of fiber material, or a mixture of plural kinds of fiber materials. It may be a thread that has been made. The yarn has a thickness of, for example, 200 to 1500 dtex, and a yarn crossing angle of 10 to 90 °. The diameter of the single yarn fiber constituting the yarn is, for example, 5 to 50 μm.

  The braided fiber reinforcement 13 may be provided on the core body so that the yarn extending in two directions extends in any direction, for example, one of them extends in the length direction of the core body. Or one of them may be provided so as to extend in the width direction of the core body, and any one of them may be provided in the length direction or width direction of the core body. It may be provided with an inclination.

  As the woven fabric, for example, a woven fabric having a basic structure such as plain weave, oblique woven fabric, satin weaving; a woven fabric having changed texture such as modified plain weave, modified oblique woven fabric, modified satin weaving; special organization such as honeycomb weaving, hackback weaving, pear weaving Woven double woven fabrics, warp double woven fabrics, double woven fabrics and other laminated fabrics; twisted woven fabrics; weft pile fabrics, warp pile woven fabric fabrics; .

  The warp and weft constituting the woven fiber reinforcing material 13 are not particularly limited, and may be a yarn composed of only one kind of fiber material, or a mixture of plural kinds of fiber materials. It may be a constructed yarn. The warp and weft have a thickness of, for example, 300 to 1500 dtex, and the crossing angle is generally 90 °. The diameter of the single yarn fiber constituting the warp and the weft is, for example, 10 to 300 μm.

  The fiber reinforcing material 13 of the woven fabric may be provided on the core body so that the warp and the weft extend in any direction. For example, one of them extends in the length direction of the core body. May be provided, or one of them may be provided so as to extend in the width direction of the core body, and any one of them may be provided with respect to the length direction or the width direction of the core body. It may be provided with an inclination.

  As the knitted fabric, knitted fabrics with basic structures such as flat knitting, rubber knitting, double-sided knitting, pearl knitting, etc .; Jacquard edition, Blister edition (change organization common to all basic organizations), Kanoko edition, back hair edition, semi-transfer edition, sinker fish net, accordion edition, boss neck pattern, spiral mesh (above, flat knitting type) (Change organization), teleco knitting, one-sided knitting, two-sided knitting, swing knitting, rope knitting, stitch knitting, milan rib, double picke (more than rubber knitting type knitting structure), mock milan rib, eight lock, three-step double knitting, single Examples thereof include knitted fabrics having a changed structure such as picket (above, double-sided knitted pattern changing structure).

  The yarn constituting the fiber reinforcing material 13 of the knitted fabric is not particularly limited, and may be a yarn constituted by only a single type of fiber material, or a mixture of a plurality of types of fiber materials. It may be a warp thread. The yarn has a thickness of, for example, 100 to 1500 dtex. The diameter of the single yarn fiber constituting the yarn is, for example, 5 to 100 μm.

  The braided fiber reinforcement 13 may be provided on the core body so that the wale and the course extend in any direction. For example, one of them extends in the length direction of the core body. May be provided, or one of them may be provided so as to extend in the width direction of the core body, and any one of them may be provided with respect to the length direction or the width direction of the core body. It may be provided with an inclination.

  The fiber reinforcing material 13 is joined to the ends and formed into a tubular shape, or is formed into a seamless tubular shape such as a bag-woven fabric, braid, or circular knitted fabric, and the hollow portion H is formed in the core body 11. Embedded in the core body 11, or formed in a sheet shape and embedded in the core body 11 so as to surround the hollow portion H, and further formed in a belt shape in the core body 11. It may be embedded by forming a spiral with the hollow portion H as the center.

  As shown in FIG. 1, the fiber reinforcing material 13 may be embedded in the inner layer of the core body 11, may be embedded in the intermediate layer of the core body 11, and further, the core body 11. It may be embedded in the outer layer.

  Next, the manufacturing method of the molding core 10 according to the present embodiment will be described with reference to FIGS. 2 (a) to 2 (c) and FIGS. 3 (a) to 3 (c).

  The core molding die 20 includes a lower mold 21 and an upper mold 22, and the lower mold 21 is provided with a lower concave groove 23 that constitutes a cavity and a guide pin 24 that protrudes upward. 22 is provided with a guide hole 25 corresponding to the guide pin 24.

First, as shown in FIG. 2 (a), the surface coating film 12 of the fluororesin film so as to extend in the lower die 21 upper surface is provided to cover the bottom and side surfaces of the lower depression 23 of the lower mold 21, down from the top thereof The uncrosslinked polymer composition R is provided in layers corresponding to the bottom and side surfaces of the side recess 23. At this time, as the surface coating film 12, one having an adhesion imparting treatment on one surface is used, and the side subjected to the treatment is set to the inner uncrosslinked polymer composition R side. Examples of the adhesion-imparting treatment include sodium treatment and corona discharge treatment, but it is preferable to use a sodium-treated one from the viewpoint of durability of adhesion performance. At this time, a topping sheet in which the uncrosslinked polymer composition R is layered on the surface coating film 12 in advance may be used.

  Next, as shown in FIG. 2B, the fiber reinforcing material 13 is provided so as to cover the cored bar 26. At this time, the fiber reinforcing material 13 may be used that has been subjected to an adhesion treatment such as an RFL treatment that is heated after being immersed in an RFL aqueous solution, or a material that has not been subjected to such an adhesion treatment. Also good. From the viewpoint of good workability of providing the fiber reinforcing material 13 on the cored bar 26, the fiber reinforcing material 13 is preferably a braid whose inner diameter is increased or decreased by compressing or expanding in the axial direction. At this time, the fiber reinforcing material 13 may be provided on the core metal 26 and the uncrosslinked polymer composition may be covered. Furthermore, the fiber reinforcing material 13 may be provided after covering the core metal 26 with the uncrosslinked polymer composition, or may be provided so as to further cover the uncrosslinked polymer composition thereon. Thereby, the embedding position of the fiber reinforcement 13 can be set.

  Next, as shown in FIG. 2 (c), the metal core 26 provided with the fiber reinforcing material 13 is provided so as to be fitted onto the uncrosslinked polymer composition R in the lower recess 23 of the lower mold 21.

Next, as shown in FIG. 3A, the uncrosslinked polymer composition R is provided in a layered manner so as to cover the cored bar 26 provided with the fiber reinforcing material 13 fitted in the lower recess 23 of the lower mold 21. Then, providing the surface coating film 12 of the fluororesin film so as to extend in the lower mold 21 upper surface with an overlying. Accordingly, a pair of surface coating films 12 are provided on the upper surface of the lower mold 21 so as to overlap each other. At this time, as the surface coating film 12, one having an adhesion imparting treatment on one surface is used, and the side subjected to the treatment is set to the inner uncrosslinked polymer composition side. At this time, a topping sheet in which the uncrosslinked polymer composition R is layered on the surface coating film 12 in advance may be used.

  Next, as shown in FIG. 3B, the upper die 22 is lowered, and the guide pin 24 is inserted into the guide hole 25 and guided to clamp the die. At this time, the mold temperature is, for example, 150 to 180 ° C., the mold clamping pressure is 0.2 to 1 MPa, and the holding time is 5 to 60 minutes. As a result, the crosslinking reaction of the uncrosslinked polymer composition R proceeds and the core body 11 is molded, and the surface coating film 12 is bonded to the core body 11 and integrally molded to cover the surface of the core body 11. The fiber reinforcing material 13 is embedded in the core body 11. Further, the surplus of the polymer composition flows from between the pair of surface coating films 12 between the lower mold 21 and the upper mold 22 to the mold-matching portion to form burrs B. As a result, the core body 11 with less internal distortion is formed. Furthermore, the surplus portion of the surface covering film 12 is also extended toward the end and similarly flows to the mold-matching portion to form the burrs B. Thereby, generation | occurrence | production of the wrinkle of the surface coating film 12 in the surface of the core 10 for shaping | molding will be suppressed.

  Then, as shown in FIG. 3C, the mold is opened, the molded body is taken out from the core molding die 20, the core metal 26 is pulled out from the molded body, and the burrs B are cut to form the molding core 10. Get. At this time, by cutting the burrs B, the molding core 10 is configured such that the surface coating film 12 is abutted at the top of the corner portion 11a of the core body 11.

  The obtained molding core 10 may be subjected to a secondary curing heat treatment with a heating temperature of 200 ° C. to 250 ° C. and a heating time of 1 to 16 hours. Thereby, the shrinkage resistance at the time of FRP molding can be improved.

  In the present embodiment, the molding core 10 has a rectangular cross-sectional shape, but is not particularly limited thereto, and may be other polygonal shapes such as a triangle and a trapezoid, Further, it may be oval or circular.

  Moreover, in this embodiment, although it was set as the molding core 10 which has the hollow part H, it is not specifically limited to this, A solid thing may be sufficient.

  Further, in the present embodiment, the sheet-like surface coating film 12 is provided so as to wrap the core body 11, but the present invention is not particularly limited thereto, and the tubular body is provided so as to cover the core body 11. The surface coating film may be provided, or the belt-like surface coating film may be provided so as to be wound around the core body 11 in a spiral manner.

INDUSTRIAL APPLICATION This invention is useful about the core for shaping | molding formed in the elongate shape used in the case of manufacture of the structural member made from FRP, and its manufacturing method .

It is a perspective view of the molding core which concerns on embodiment. (A)-(c) is explanatory drawing which shows the first half of the manufacturing method of the molding core which concerns on embodiment. (A)-(c) is explanatory drawing which shows the second half of the manufacturing method of the molding core which concerns on embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Molding core 11 Core main body 11a Corner | angular part 12 Surface coating film

Claims (11)

A molding core formed in an elongated shape,
A core body formed of a viscoelastic material made of a crosslinked polymer composition and having a corner portion extending along the length direction ;
Before SL and the surface coating film comprising a fluororesin film which is provided so as core body and is integrally molded butted at the top of the corner of and the core body covers the surface of the core body ,
Formed shape for the core with a. In the molding core according to claim 1,
The molding core has a hollow portion extending in the length direction,
A molding core in which a fiber reinforcing material is embedded in the core body so as to surround the hollow portion. A manufacturing method of a molding core formed in an elongated shape,
The molding core is formed of a viscoelastic material made of a crosslinked polymer composition and has a core body having a corner extending along the length direction, and the core body is integrally molded with the core body. A surface covering film composed of a fluororesin film that covers the surface of the core body and is provided to be abutted at the top of the corner of the core body, and
A first surface coating film is provided so as to cover the bottom and side surfaces of the lower recess of the lower mold constituting the cavity and extend to the upper surface of the lower mold, and an uncrosslinked polymer composition is formed on the first surface coating film of the lower recess Providing a step;
Providing a second surface coating film so as to cover the uncrosslinked polymer composition provided in the lower recess of the lower mold and extend to the upper surface of the lower mold and overlap the first surface coating film;
An upper mold is provided on the lower mold and clamped, and held at a predetermined mold temperature and clamping pressure for a predetermined time to crosslink the uncrosslinked polymer composition to mold a core body, and Adhering the first and second surface coating films to the core body and integrally molding the core body with the first and second surface coating films; and
The upper mold and the lower mold are opened, and a molded body is taken out. From the molded body, the first and second surface coatings between the lower mold and the upper mold are caused by an excess of the uncrosslinked polymer composition. Cut the burrs formed by flowing from the film to the mold matching part, and the burrs formed by flowing the excess of the first and second surface coating films toward the end and flowing to the mold matching part. A step of obtaining a molding core having a corner portion where the surface coating film is abutted at the top; and
The manufacturing method of the core for shaping | molding containing. In the manufacturing method of the molding core described in Claim 3,
The manufacturing method of the molding core which uses what the surface which becomes the said uncrosslinked polymer composition side as the said 1st and 2nd surface coating film performs the alkali treatment or corona discharge treatment by metallic sodium. In the manufacturing method of the molding core described in Claim 3 or 4,
The manufacturing method of the molding core which uses as a said 1st and 2nd surface coating film the thing which topped the uncrosslinked polymer composition on the surface used as the said uncrosslinked polymer composition side. In the manufacturing method of the molding core as described in any one of Claims 3 thru | or 5,
The molding core has a hollow portion extending in the length direction,
Manufacture of a molding core further comprising a step of disposing a cored bar for forming the hollow portion so as to be embedded in the uncrosslinked polymer composition provided on the first surface coating film of the lower concave portion. Method. In the manufacturing method of the molding core described in Claim 6,
In the molding core, a fiber reinforcing material is embedded in the core body so as to surround the hollow portion,
The manufacturing method of the molding core further including the step of providing a fiber reinforcement so that the said core metal may be covered, before arrange | positioning the said metal core so that it may be embedded at the said uncrosslinked polymer composition. In the manufacturing method of the molding core described in Claim 7,
A method for producing a molding core, further comprising the step of providing the fiber reinforcement after covering the cored bar with an uncrosslinked polymer composition. In the manufacturing method of the molding core described in Claim 7 or 8,
A method for producing a molding core, further comprising a step of providing the fiber reinforcing material on the core metal so as to cover the uncrosslinked polymer composition. In the manufacturing method of the molding core as described in any one of Claims 7 thru | or 9,
A method for producing a molding core using a tubular assembly whose inner diameter is increased or decreased by compressing or expanding in the axial direction as the fiber reinforcing material. In the manufacturing method of the molding core as described in any one of Claims 3 thru | or 10,
A method for producing a molding core, further comprising a step of subjecting a molding core obtained by molding to a secondary curing heat treatment at a heating temperature of 200 ° C to 250 ° C and a heating time of 1 to 16 hours.

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