JP2022039630A - Manufacturing method of cover lid, and cover lid - Google Patents

Abstract

To provide a method for manufacturing a cover lid that is strong, lightweight, and has a good corrosion resistance, and the cover lid.SOLUTION: A cover lid is manufactured by: placing a first glass mat, a first multi-axis continuous glass-fiber sheet, a composite body formed of a plate-shaped paper honeycomb core and a foamed particle molded body having voids with a three-dimensional network structure in which a plurality of foamed particles filled in cells of the core are molded, a second multi-axis continuous glass-fiber sheet, and a second glass mat on a molding space formed by a lower die and an upper die; cramping the lower mold and the lower mold; depressurizing the molding space formed by the lower mold and the upper mold; injecting a liquid raw material of a thermosetting resin into the molding space; and curing the filled thermosetting resin. In the cover lid, a layer of a glass-fiber reinforced plastic is formed around the composite body, and the composite body is formed by curing the resin filled in the voids of the three-dimensional network structure of the foamed particle molded body, and a layer of the glass-fiber reinforced plastic and the composite body are integrated via a multi-axis continuous glass-fiber sheet.SELECTED DRAWING: Figure 7

Description

The present invention relates to a method for manufacturing a cover and a cover to be installed at an opening of a water treatment facility such as a water purification plant or a sewage treatment plant.

Covers are installed at the openings of water treatment facilities for the purpose of deodorizing, preventing falls, and preventing the introduction of dangerous substances.
FIG. 10 shows a plan view of a cover with a handle, which is commonly used in water treatment facilities.
In this figure, 19 is a cover and 20 is a handle. The handles 20 are usually attached to two places of the cover 19, and are used when an operator carries the cover 19 or removes the cover to the side of the opening of the water treatment facility. The handle 20 is attached to the cover by a rivet or the like. The handle 20 is attached as needed and is not essential. The cover 19 is usually placed on a receiving frame (not shown) provided at the opening of the water treatment facility. Further, a lock device (not shown) may be attached to the cover 19 so that the cover cannot be opened from the receiving frame without permission. The cover shown in FIG. 10 has an uneven pattern formed on the upper surface thereof.

Conventionally, a cover made of synthetic resin such as an iron plate or FRP has been used.
Although the iron plate cover has high strength, it is heavy and difficult to handle such as opening and closing the cover when inspecting the facility, and it also has difficulty in corrosion resistance. The FRP cover is relatively lighter and has excellent corrosion resistance as compared with the iron plate cover, but when a worker rides on the cover, the deflection is large and there is a practical problem.

Therefore, as a cover to solve the above problems, a sandwich panel obtained by injecting and foaming a rigid polyurethane foam material into a gap between two FRP molded plates is cut out to a predetermined size, and a foam surface such as a cut end is synthesized. A cover covering characterized by being coated with a resin has been developed (Patent Document 1).

However, even with the cover described in Patent Document 1, if the thickness is about 30 mm, the deflection is large when a person such as a worker gets on the cover, and in order to reduce this deflection, the thickness of the FRP molded plate is increased. It needs to be made thicker, the weight of the cover is heavier, and the price is inevitably high.

Patent Document 1 Japanese Patent Application Laid-Open No. 7-259111

In view of the above problems, it is an object of the present invention to provide a method for manufacturing a cover and a cover, which have good corrosion resistance, high strength, and are lightweight.

The present invention employs the following means in order to solve the above problems.
[1] A method of manufacturing a cover from a molded product obtained by injecting resin into the molding space formed by the lower mold and the upper mold, and the molding space formed by the lower mold and the upper mold has a flat plate-like three-dimensional shape. There is a process of laying the first glass mat in the lower cavity so that the bottom and sides of the lower cavity are covered and the edges protrude from the cavity, the first glass mat is the lower cavity. The step of laying the first multi-axis continuous glass fiber sheet in the recess formed in the tee, and the upper surface of the first multi-axis continuous glass fiber sheet is filled with a plate-shaped paper honeycomb core and cells of the core. A step of laying a composite with a foamed particle molded body having voids having a three-dimensional network structure in which a plurality of foamed particles are molded, and a second multiaxial continuous glass fiber sheet is laid on the upper surface of the composite. Step, step of laying the second glass mat on the upper surface of the second multi-axis continuous glass fiber sheet, the lower mold and the upper mold are formed after the upper mold is placed on the above lower mold and the mold is fastened. The steps of depressurizing the molding space, then injecting the liquid raw material of the thermosetting resin into the molding space, curing the filled liquid raw material of the thermosetting resin, and releasing the cured molded product are performed. A method for manufacturing a cover, which comprises.
[2] The method for producing a cover according to [1], which comprises a step of cutting the released molded product and applying a synthetic resin to a cut end formed by cutting.
[3] The method for manufacturing a cover according to [1] or [2], wherein an uneven pattern is formed on the bottom surface of the lower die cavity.
[4] A composite of a plate-shaped paper honeycomb core and a foamed particle molded body having a resin-cured portion having a three-dimensional network structure formed by molding a plurality of foamed particles filled in the cells of the core. It is characterized in that a layer of glass fiber reinforced plastic is formed around it, and the layer of glass fiber reinforced plastic and the composite are integrally bonded via a multiaxial continuous glass fiber sheet. Cover.
[5] A composite of a plate-shaped paper honeycomb core and a foamed particle molded body having a resin-cured portion having a three-dimensional network structure formed by molding a plurality of foamed particles filled in the cells of the core. A molded product in which a layer of glass fiber reinforced plastic is formed around the periphery and the layer of glass fiber reinforced plastic and the composite are integrally bonded via a multiaxial continuous glass fiber sheet is cut in the thickness direction. A cover made by applying synthetic resin to the cut end.

The cover of the present invention is a composite of a plate-shaped paper honeycomb core and a foamed particle molded body having voids having a three-dimensional network structure in which a plurality of foamed particles filled in the cells of the core are molded. By sandwiching it between axial continuous glass fiber sheets, wrapping it in a glass mat, and injecting resin into the molding, the resin is filled in the voids of the three-dimensional network structure of the foamed particle molded body and cured. A layer of glass fiber reinforced plastic formed by filling a glass mat and hardening is formed around the composite, and the layer of the glass fiber reinforced plastic is connected to the composite via a multiaxial continuous glass sheet. It is integrally bonded, and not only has good corrosion resistance, but also has high strength and light weight.

(A) schematically describes the lower mold, the material laid on the lower mold (glass mat, multi-axis continuous glass fiber sheet, composite of honeycomb core and foamed particle molded body formed in the core), and upper mold. Shown in. (B) shows an enlarged view of a part of (a). The structure of the multi-axis (4-axis) continuous glass sheet is schematically shown. The perspective view of the plate-shaped paper honeycomb core is shown. (A) is a composite (plate-shaped composite) of a plate-shaped paper honeycomb core and a foamed particle molded body having a gap portion of a three-dimensional network structure in which a plurality of foamed particles filled in the cells of the core are molded. The perspective view of the body) is shown. (B) shows an enlarged view of a part of (a). The perspective view of the lower mold in which the plate-like composite is laid is shown. FIG. 3 shows a cross-sectional view of a lower mold in which a first glass mat, a first multi-axis continuous glass fiber sheet, a foamed particle molded body, and a second multi-axis continuous glass sheet are laid. The lower mold, the material of the molded product, and the upper mold provided with the suction pipe and the injection pipe are shown. The molded product cured in the molding space formed by the lower mold and the upper mold is schematically shown. The cross section of the molded product released from the mold is schematically shown. The plan view of a general cover is shown.

In the cover of the present invention, the material of the molded product is placed in a pair of molding dies consisting of a lower mold and an upper mold, the mold is closed, and then resin is injected to impregnate the material of the molded product into molding. Manufactured.
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1A shows the lower mold 1 and the upper mold 2 forming the molding space, and the materials of the molded product arranged in the molding space.
The materials of the molded product arranged in the molding space are a first glass mat 3, a first multi-axis continuous glass fiber sheet 4, a plate-shaped paper honeycomb core, and a three-dimensional network structure in the cell of the core. A composite 5 with a foamed particle molded body having voids, a second multiaxial continuous glass fiber sheet 6, and a second glass mat 7.
In FIG. 1, the upper mold 2 is located above the lower mold 1, and the state before the lower mold 1 and the upper mold 2 are molded is shown.
Note that FIG. 0 shows a packing made of an elastic material provided on the surface of the lower mold 1. As will be described later, the packing 0 is a member that provides a sealing effect on the mating surface of the lower mold 1 and the upper mold 2 when the lower mold 1 and the upper mold 2 are molded.

The glass mat is made by randomly stacking short pieces of glass fibers and processing them into a mat shape (cloth shape), which can be used as a base material of fiber reinforced plastic (FRP). Glass mats of various dimensions are commercially available and easily available. As can be seen from FIG. 1, two glass mats, that is, the first glass mat 3 and the second glass mat 7 are arranged in the lower mold 1.

The multi-axis continuous glass fiber sheet is made by arranging continuous long glass fibers in a plurality of directions to form a sheet. One sheet is composed of multi-axis fibers and has high strength in a plurality of directions. , Suitable as a reinforcing material. For example, a 4-axis continuous glass fiber sheet is made by stacking fibers of 0 °, −20 to 160 °, +20 to +160 °, and 90 ° in four directions into one sheet (see FIG. 2).
As the multi-axis continuous glass fiber sheet, there are multi-axis ones having two or more axes, but a four-axis continuous glass fiber sheet is desirable for the lid.
Multiaxial continuous glass fiber sheets are commercially available and easily available.
As can be seen from FIG. 1, two multi-axis continuous glass sheets, that is, a first multi-axis continuous glass fiber sheet 4 and a second multi-axis continuous glass fiber sheet 6 are arranged.

The composite of the honeycomb core made of plate-shaped paper and the foamed particle molded body having the voids of the three-dimensional network structure in the cell of the core (hereinafter referred to as “plate-shaped composite”) 5 is a plate-shaped paper. A plurality of resin-made foamed particles are filled in a cell of a honeycomb core, and the foamed particles are heated before and after the melting point of the resin to fuse the plurality of foamed particles in the cell to form a void portion having a three-dimensional network structure. The formed foamed particle molded body is further removed by cutting the side surface thereof, and is a composite of a paper honeycomb core and a foamed particle molded body. Its shape is a plate with the same thickness as the paper honeycomb core.

FIG. 3 shows a plate-shaped paper honeycomb core 8. In the figure, 9 and 10 are cells and cell walls of the honeycomb core, respectively. Then, FIG. 4A shows a plate-shaped complex 5, and FIG. 4B shows an enlarged view of a part thereof.
In a narrow sense, the honeycomb core refers to a structure in which cells having a regular hexagonal cross-sectional shape are arranged without gaps, but here, it refers to a core in a broad sense, and the cross-sectional shape is not limited to a regular hexagonal shape but is a trapezoid. It also includes those with a structure in which cells other than regular hexagons such as triangles and triangles are arranged without gaps. FIG. 3 shows cells having a trapezoidal cross section arranged without gaps.
A three-dimensional mesh-like void portion 12 is formed in the fused foamed particle molded body formed in the cell 9 of the paper honeycomb core 8 [see FIG. 4 (b)]. As will be described later, the void portion 12 is filled with a thermosetting resin at the time of molding.
In the plate-shaped composite 5, the resin of the foamed particles 11 slightly permeates the cell wall 10 of the paper honeycomb core 8, so that the foamed particle molded body does not fall off from the cell wall 10 of the honeycomb core.

The resin of the foamed particles 11 in the cell 9 of the paper honeycomb core 8 is preferably a thermoplastic resin, for example, a polystyrene resin, a polyethylene resin, a polypropylene resin, polybutylene succinate, polyethylene terephthalate, or polylactic acid. Such as polyester resin, polycarbonate resin, polyvinyl chloride resin and the like can be mentioned.

The porosity of the foamed particle molded body of the plate-shaped composite 5 (the ratio of the void portion 12 of the three-dimensional network structure to the foamed particle molded body) is preferably 3 to 30% by volume. As will be described later, the voids of the network structure are filled (impregnated) with the thermosetting resin, but if the porosity is less than 3% by volume, the amount of the thermosetting resin that can be impregnated (filled) is small. , It is not possible to obtain a molded product or cover with sufficient strength. Further, when the porosity exceeds 30% by volume, the amount of the thermosetting resin to be filled becomes large, and a lightweight cover cannot be obtained. The particle size of the foamed particles is preferably 1.0 to 3.5 mm from the viewpoint of easy filling of the thermosetting resin and improvement of the strength of the composite of the foamed molded plate and the thermosetting resin.
Such a plate-shaped composite 5 is commercially available from a manufacturer of foamed plastic such as JSP Co., Ltd.

The cover of the present invention is manufactured through a manufacturing process including steps 1 to 8 or steps 1 to 9 shown below.
<About process 1>
The first glass mat 3 is provided along the bottom surface and the side surface of the lower mold 1 so that the edge thereof protrudes from the peripheral edge of the cavity of the lower mold 1 as shown in FIGS. 1 and 5 to 7. Will be laid. Therefore, the laid first glass mat 3 is formed with a recess having substantially the same shape as the cavity of the lower mold 1.
As will be described later, the first glass mat 3 is filled (impregnated) with a thermosetting resin to form a layer of glass fiber reinforced plastic (GFRP).

<About process 2>
Next, as shown in FIG. 1, the first multi-axis continuous glass fiber sheet 4 is laid in the recess of the first glass mat 3.
Since the thickness of the first multiaxial continuous glass fiber sheet 4 is thin, the bottom surface of the recess is slightly raised, but most of the recesses are still maintained. The planar shape of the first multiaxial continuous glass fiber sheet 4 to be laid is the same as the planar shape of the concave portion of the first glass mat 3.

<About process 3>
Next, the plate-shaped composite 5 is laid on the upper surface of the first multi-axis continuous glass fiber sheet 4 laid in the recess of the first glass mat 3.
The planar shape of the plate-shaped composite 5 to be laid is the same as that of the first multiaxial continuous glass fiber sheet 4, and therefore the planar shape of the recess of the first glass mat 3.

<About process 4>
Next, a second multi-axis continuous glass fiber sheet 6 is further laid on the laid plate-shaped composite 5.
The second multiaxial continuous glass fiber sheet 6 is laid on the entire surface of the plate-shaped composite 5.

<About process 5>
The entire surface of the multi-axis continuous glass fiber sheet 6 is placed on the upper surface of the second multi-axis continuous glass fiber sheet 6 laid on the plate-shaped composite 5 laid over the entire concave portion of the first glass mat 3. A second glass mat 7 is laid so as to cover it (see FIG. 1).
<About process 6>
As described above, in the cavity of the lower mold 1, the first glass mat 3, the first multi-axis continuous glass fiber sheet 4, the plate-like composite 5, the second multi-axis continuous glass fiber sheet 6, and the second. When the laying of the glass mat 7 is completed, the upper mold 2 is put on the lower mold 1 and pressed to fasten the mold. In the molded state, the lower mold 1 and the upper mold 2 form a molding space having a flat plate-like three-dimensional shape. Then, a connected decompression suction valve (not shown) such as a vacuum pump is opened, and as shown in FIG. 7, the molding space is depressurized from the decompression suction pipe 13 provided in the upper mold 2. When the mold is fastened, the packing 0 is pressed and deformed, the mating surfaces of the lower mold 1 and the upper mold 2 are sealed, and the molding space is surely depressurized.
When filling the liquid raw material of the thermosetting resin, the decompression degree is preferably in the range of −0.01 to −0.1 MPa (G) in order to make the degree of decompression uniform in the molding space. In addition, (G) means gauge pressure.

One or two or more decompression suction pipes 13 are provided at the center of the upper die 2 in the longitudinal direction and the width direction. When two pipes 13 are provided, they may be provided at the central portion in the longitudinal direction of the upper die and at intervals in the width direction. FIG. 7 shows a decompression suction pipe 13 provided in the central portion in the longitudinal direction of the upper die.

Next, the liquid raw material of the thermosetting resin is injected into the molding space. The injection of the resin may be started at the same time as the depressurization, but the depressurization is preferably performed before the liquid raw material of the thermosetting resin is added. By depressurizing the entire molding space before injecting the liquid raw material of the thermosetting resin, the liquid raw material of the thermosetting resin to be injected into the molding space is transferred to the first glass mat 3 and the first multi-axis continuous. It is possible to fill (impregnate) the glass fiber sheet 4, the three-dimensional network-like structure gap portion 12 of the plate-shaped composite 5, the second multiaxial continuous glass fiber sheet 6, and the second glass mat 7. At the same time as filling (impregnating) these portions, the paper of the honeycomb core of the plate-shaped complex is also impregnated with the liquid raw material of the thermosetting resin. Hereinafter, the liquid raw material of the thermosetting resin may be simply referred to as "resin liquid raw material".

The injection pipes 14 for the resin liquid raw material are provided at two locations in total, one in the vicinity of both ends in the longitudinal direction of the upper mold 2, and the two injection ports are the ends in the longitudinal direction of the molding space and are in the width direction. It is desirable to position it in the center. In order to improve the efficiency of injection, the upper die 2 may be provided in the central portion in the width direction at a slight distance from the end portion in the longitudinal direction, and may be provided in a total of three or more locations. FIG. 7 shows the decompression suction pipe 13 and the injection pipes 14 provided at two locations near both ends of the upper die 2 in the longitudinal direction.

Thermocurability to be filled (impregnated) in the first glass mat 3, the first multi-axis continuous glass fiber sheet 4, the plate-like composite 5, the second multi-axis continuous glass fiber sheet 6 and the second glass mat 7. As the resin, epoxy resin, unsaturated polyester resin, vinyl ester resin, dicyclopentadiene resin, polyurethane resin, silicon resin, phenol resin, melamine resin, polyimide resin, urea resin , Dialyl phthalate-based resins and modified resins thereof and the like can be mentioned. These thermosetting resins are used in the state of a liquid raw material mixed with a cross-linking monomer, a curing accelerator, an additive and the like. Further, in response to such a thermosetting resin, it is preferable to add a curing agent capable of reacting with the thermosetting resin to form a cured product.

<About process 7>
When the filling is completed, the curing of the resin liquid raw material proceeds. Depending on the curing characteristics of the resin, curing may proceed with filling. FIG. 8 schematically shows the molded product 15 that cures in the molding space. In this figure, in the molded product 15, the peripheral portion (hatched portion) is the portion of the first and second glass mats filled (impregnated) with the thermosetting resin, and the central portion (black portion) is the thermosetting resin. It is a portion of the plate-shaped composite plate 5 whose upper surface and lower surface are sandwiched between the first multi-axis continuous glass fiber sheet 4 and the second multi-axis continuous glass fiber sheet 6 filled with (impregnated). The peripheral portion (hatched portion) and the central portion (black portion) are integrated to form the molded product 15.
<About process 8>
After the curing is completed, the molded product 15 is released from the lower mold 1 and the upper mold 2.
As can be seen from FIG. 8, in this molded product 15, the edge portion of the first glass mat 3 sandwiched between the peripheral portions of the lower mold 1 and the upper mold 2 is formed as a burr 18, and is therefore removed by cutting. do. FIG. 9 schematically shows a cross section of the molded product 15 from which the burrs 18 have been cut and removed after mold release.

Since the outer periphery of the molded product 15 is hardened by filling the first glass mat 3 and the second glass mat 7 with a resin liquid raw material, a layer of glass fiber reinforced plastic (GFRP) is formed.
Then, the resin liquid raw material is also filled and cured in the three-dimensional mesh-like void portion 12 [see FIG. 4 (b)] of the foamed particle molded body of the plate-shaped composite 5, and further, the upper surface of the plate-shaped composite 5 is formed. The first and second multiaxial continuous glass fiber sheets arranged on the lower surface and sandwiching the plate-shaped composite 5 are also impregnated with the resin liquid raw material and cured.
Therefore, a plate-like composite having an upper surface and a lower surface sandwiched between a layer of glass fiber reinforced plastic (GFRP) formed by the first and second glass mats 3 and 7 and a first and second multiaxial continuous glass fiber sheet. It is integrated with 5 to form the molded product 15.

The layer of glass fiber reinforced plastic (GFRP) formed on the outer periphery of the molded product 15 preferably has a thickness of about 1 to 3 mm. As the thickness of this layer increases, the weight of the molded product 15 increases, and the weight of the cover cannot be reduced.
The thickness of the layer of glass fiber reinforced plastic (GFRP) can be easily adjusted by adjusting the thickness of the first and second glass mats 3 and 7.

FIG. 9 schematically shows a cross section including the surface of the molded product 15. In this figure, the shaded areas other than the cell wall 10 of the honeycomb core of the plate-shaped composite 5 are the first and second glass mats 3, 7, and the first and second multiaxial continuous glass fiber sheets 4, 6 and the plate. The site of the thermosetting resin filled and cured in the void portion 12 of the three-dimensional network structure formed in the foamed particle molded body of the shape composite 5 is shown.
As can be seen from this figure, in the molded product 15, a layer of glass fiber reinforced plastic is formed on the outer periphery thereof, and the void portion 12 of the three-dimensional network structure of the plate-like composite 5 is also filled with the resin liquid raw material. Since it is cured, the cured product is distributed in a three-dimensional network in the plate-shaped composite 5, and the strength of the plate-shaped composite itself is dramatically improved. Further, the multi-axis continuous glass fiber sheets 4 and 6 sandwiching the upper surface and the lower surface of the plate-shaped composite 5 further enhance the strength of the molded product 15. Further, the paper of the cell wall 10 of the honeycomb core of the plate-shaped complex is also impregnated with the resin liquid raw material and cured, which contributes to the improvement of the strength of the molded product 15.
Further, the plate-shaped composite 5 in which the void portion 12 is filled with the resin is relatively lightweight because the foamed particles 11 occupy the portion other than the void portion.

The molded product 15 can be used as a cover by adjusting the dimensions of the lower mold 1 and the upper mold 2 so that the molding space formed by both is the same as the size of the cover. As described above, this cover covers a cured portion of a thermosetting resin having a three-dimensional network structure formed by molding a plate-shaped paper honeycomb core and a plurality of foam particles filled in the cells of the core. A layer of glass fiber reinforced plastic is formed around the composite with the foamed particle molded body, and the layer of glass fiber reinforced plastic and the composite are integrally bonded via a multiaxial continuous glass fiber sheet. Therefore, it not only has good corrosion resistance, but also has high strength and light weight.

Further, as shown in the following step 9, the molded product 15 is manufactured to be larger than the area of the cover and have the same thickness as the cover, and then cut in the thickness direction according to the dimensions of the cover. It can also be a cover.
<About process 9>
The molded product 15 is cut in the thickness direction to produce a cover having a desired size. Since the cut end of the foam molded plate is exposed on the side surface of the cover after cutting, a synthetic resin such as unsaturated polyester resin is applied to the cut end surface from the viewpoint of durability and aesthetics.

An example of manufacturing a plurality of cover covers by cutting the molded product to the size of the cover cover is as follows.
When the dimensions of the cover are, for example, 900 mm in length, 450 mm in width, and 30 mm in thickness, when a molded product 8 having dimensions of 2700 mm in length, 900 mm in width, and 30 mm in thickness is manufactured, the molded product 8 is cut into 6 pieces. Can be manufactured. Further, if it is within the area of the molded product 8, it can be cut to produce a cover having a desired size.

As described above, the cover covered by the step 9 is formed by molding a plate-shaped paper honeycomb core and a plurality of foam particles filled in the cells of the core on the surface other than the cut end. A layer of glass fiber reinforced plastic is formed around the composite 5 with a foamed particle molded body having a cured portion of a thermosetting resin having a dimensional network structure, and there are many layers of glass fiber reinforced plastic and the composite. Since it is integrally bonded via a shaft continuous glass fiber sheet, it has high strength, good corrosion resistance, and is lightweight.

An embossed pattern may be formed on the surface of the cover to make it easier for the operator to walk or to make the visual sense effective.
If an uneven pattern to which the embossed pattern is transferred is formed on the bottom surface of the cavity of the lower mold 1, the embossed pattern can be formed on the lower surface of the molded product 8 as shown in FIG. An embossed pattern can be formed on the surface of the cover 19. Since an embossed pattern is not normally formed on the back surface of the cover 19, the uneven pattern may be formed only on the bottom surface of the cavity of the lower mold 1.

0: Packing 1: Lower mold 2: Upper mold 3: First glass mat 4: First multi-axis continuous glass fiber sheet 5: Plate-shaped paper honeycomb core and multiple foams filled in the cells of the core Composite with foamed particle molded body having voids in a three-dimensional network structure in which particles are molded (plate-shaped composite)
6: Second multi-axis continuous glass fiber sheet 7: Second glass mat 8: Plate-shaped paper honeycomb core 9: Plate-shaped paper honeycomb core cell 10: Plate-shaped paper honeycomb core cell wall 11: Foamed particles 12: Three-dimensional mesh-like voids formed in the foamed particle molded body 13: Decompression suction pipe 14: Injection pipe 15: Molded product 16: Peripheral portion 17: Central portion 18: Burr 19: Cover 20: handle

Claims (5)

It is a method of manufacturing a cover from a molded product obtained by injecting resin into the molding space formed by the lower mold and the upper mold.
The molding space formed by the lower mold and the upper mold is a flat plate-like three-dimensional shape.
A process of laying a first glass mat in the lower die cavity so that the bottom and sides of the lower die cavity are covered and the edges protrude from the lower die cavity.
The step of laying the first multi-axis continuous glass fiber sheet in the recess formed by the first glass mat in the lower cavity.
Foam particle molding having a three-dimensional network-like void portion in which a plate-shaped paper honeycomb core and a plurality of foam particles filled in the cells of the core are formed on the upper surface of the first multi-axis continuous glass fiber sheet. The process of laying a complex with the body,
Step of laying a second multiaxial continuous glass fiber sheet on the upper surface of the complex,
The process of laying the second glass mat on the upper surface of the second multi-axis continuous glass fiber sheet,
A step of depressurizing the molding space formed by the lower mold and the upper mold after placing the upper mold on the lower mold and then injecting a liquid raw material of a thermosetting resin into the molding space.
The process of curing the liquid raw material of the filled thermosetting resin,
A method for manufacturing a cover, which comprises a step of releasing a cured molded product. The method for manufacturing a cover according to claim 1, further comprising a step of cutting the released molded product and applying a synthetic resin to the cut end formed by the cutting. The method for manufacturing a cover according to claim 1 or 2, wherein an uneven pattern is formed on the bottom surface of the lower die cavity. Glass around a composite of a plate-shaped paper honeycomb core and a foamed particle molded body having a resin-cured portion of a three-dimensional network structure formed by molding a plurality of foamed particles filled in the cells of the core. A cover comprising a molded product in which a layer of fiberglass reinforced plastic is formed and the layer of glass fiberglass reinforced plastic and the composite are integrally bonded via a multiaxial continuous glass fiber sheet. Glass around a composite of a plate-shaped paper honeycomb core and a foamed particle molded body having a resin-cured portion of a three-dimensional network structure formed by molding a plurality of foamed particles filled in the cells of the core. A molded product in which a layer of fiberglass reinforced plastic is formed and the layer of glass fiberglass reinforced plastic and the composite are integrally bonded via a multiaxial continuous glass fiber sheet is cut in the thickness direction and cut into a cut end. A cover that is characterized by being coated with synthetic resin.

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