| 摘要 |
PURPOSE:To make cores with high accuracy through a simple facility, by bonding the part other than folded parts of a plurality of folded sheet members, extending a part of the folded part to shape of chrysanthemum flower after cutting off a part of the folded part, and bonding the members at both ends. CONSTITUTION:A plurality of sheet members 10a folding thin material with light weight like aluminum foil are overlaid, and after they are bonded with an adhesives 10c except around a folded part 10b, they are cut off by leaving a part of the folded part 10b, e.g., at the position shown in chain lines in figure. Next, the opposite side of the folded part 10b is compressed to one point, the folded part is opened and extended into shape of chrysanthemum flower, the sheet members at the both ends are bonded to form the core member in which the external circumference is circular and the thickness changes along a radial line. When the part is cut off at the position shown in chain lines in figure, the cross section of the core member is a chevron type. Other shapes can be obtained depending on the cut position. The similar result can be obtained by folding in zigzag for one sheet member in place of a plurality of sheet members. |
