Mold for manufacturing composite material molded product, and method for manufacturing composite material molded product
A composite material molded product has a hollow portion, a bent portion, or a curved portion in a transverse section thereof. When the composite material molded product has, for example, a bent portion, a surface on an inside of the bent portion is a pressed surface. A mold includes a pressing body that is thermally expandable and has an outer surface shape corresponding to a shape of a pressed surface, and a mold main body including a cavity accommodating the laminate and the pressing body inside, the cavity including an inner surface shape corresponding to a shape other than the pressed surface. The cavity is sealed in a state that the pressing body is disposed in the cavity. The laminate is accommodated in a molding space formed between an inner surface of the cavity and an outer surface of the pressing body.
1 . A method for manufacturing a composite material molded product, the method comprising:
disposing a laminate of prepregs in a cavity between an outer mold and an inner mold of a mold main body;
disposing a pressure distributor in the cavity;
disposing an expansion core in the cavity, wherein the expansion core expands itself, the expansion core is in contact with an outer surface of the pressure distributor and an inner surface of the pressure distributor is in contact with a surface of the laminate before expansion of the expansion core;
sealing the cavity, between the outer mold to the inner mold, by fastening the inner mold to the outer mold with fasteners;
heating the mold main body including the outer mold and the inner mold without pressing to expand the expansion core;
curing the laminate; and
distributing, during the curing, a pressing force to the laminate by the pressure distributor due to expansion of the expansion core, wherein
the cavity is sealed so that a volume of the cavity does not change during the heating, the curing and the distributing,
the laminate is formed into a C-shape
the inner mold is positioned to be enclosed by a first portion of the laminate, a second portion of the laminate and a third portion of the laminate, such that the inner mold is in contact with the inner surface of the laminate,
the pressure distributor is disposed so as to be contiguous over the first, second and third portions and in contact with the outer surface of the first, second and third portions,
the expansion core covers the outer surface of the pressure distributor in a manner that is contiguous over the first, second and third portions, and
the outer mold is positioned adjacent to the outer surface of the expansion core.
2 . The method according to claim 1 , wherein the expansion core thermally expands due to heating.
3 . The method according to claim 2 , wherein the expansion core has a concavo-convex structure that adjusts pressing force due to thermal expansion.
4 . The method according to claim 2 , wherein a thermal expansion coefficient of the expansion core is larger than a thermal expansion coefficient of the pressure distributor.
5 . The method according to claim 1 , wherein the heating includes heating the mold main body with a heater.
6 . The method according to claim 1 , wherein the blowing the compressed air is performed via a pressure hole communicating with an outside of the mold main body.
7 . The method according to claim 1 , wherein the expansion core includes dimples on an outer surface of the expansion core.
8 . The method according to claim 1 , wherein the pressure distributor is in contact with an entire outer surface of the first, second and third portions when viewed in a cross section of the laminate from a side.
9 . The method according to claim 1 , wherein the expansion core covers an entire outer surface of the pressure distributor when viewed in a cross section of the laminate from a side.
10 . A method for manufacturing a composite material molded product, the method comprising:
disposing a laminate of prepregs in a cavity between an outer mold and an inner mold of a mold main body:
disposing a pressure distributor in the cavity;
disposing an expansion core in the cavity, wherein the expansion core expands itself, the expansion core is in contact with an outer surface of the pressure distributor and an inner surface of the pressure distributor is in contact with a surface of the laminate before expansion of the expansion core;
sealing the cavity, between the outer mold to the inner mold, by fastening the inner mold to the outer mold with fasteners;
blowing compressed air into the expansion core to expand the expansion core;
curing the laminate; and
distributing, during the curing, a pressing force to the laminate by the pressure distributor due to expansion of the expansion core, wherein
the cavity is sealed so that a volume of the cavity does not change during the blowing, the curing and the distributing,
the laminate is formed into a C-shape,
the inner mold is positioned to be enclosed by a first portion of the laminate, a second portion of the laminate and a third portion of the laminate, such that the inner mold is in contact with the inner surface of the laminate,
the pressure distributor is disposed so as to be contiguous over the first, second and third portions and in contact with the outer surface of the first, second and third portions,
the expansion core covers the outer surface of the pressure distributor in a manner that is contiguous over the first, second and third portions, and
the outer mold is positioned adjacent to the outer surface of the expansion core.
11 . The method according to claim 10 , wherein the expansion core includes dimples on an outer surface of the expansion core.
12 . The method according to claim 10 , wherein the pressure distributor is in contact with an entire outer surface of the first, second and third portions when viewed in a cross section of the laminate from a side.
13 . The method according to claim 10 , wherein the expansion core covers an entire outer surface of the pressure distributor when viewed in a cross section of the laminate from a side.