| 摘要 |
<p>PURPOSE:To raise the productivity of a cylindrical product such as the drum cylinder of a musical instrument or the like by a method wherein fiber reinforced thin molded sheets are installed onto the outer surface of a cylindrical inner mold and onto the inner surface of a cylindrical outer mold and, after both the molds are fitted to each other, filling material is poured in a gap made between both the molds. CONSTITUTION:A molded sheet, which is produced by laminating carbon fiber- containing unidirectional prepregs with epoxy resin as matrix, is trimmed in a parallelo gram so as to be brought into close contact with the surface of an iron inner mold in such a manner that its ends are abutted against each other and the resultant seam is temporarily fixed by adhesive in order to form an inner skin. An outer skin is also formed similarly. After that, a cylindrical inner mold 4, onto the outer surface of which the inner skin 1 is temporarily fixed, and a cylindrical outer mold 5, onto the inner surface of which the outer skin 2 is temporarily fixed, are fittingly assembled. After that, glass fiber-containing epoxy resin is poured in a gap between both the molds. After the resin completely hardens, both the molds are demolded in order to obtain a drum cylinder, the abutted seam of which is inconspicuous, the thickness of which is uniform and in the filler resin layer 3 of which no bubble is present at all.</p> |
