| 摘要 |
PURPOSE:To provide a casting which can maintain an intricate shape and facilitates rapping by butting the side parts of plural metallic pieces, via stationary plates, to form an outside circumferential part, and further expanding forcibly the metallic pieces to the outside by using a jig. CONSTITUTION:The outside circumferential part of a core 10 is formed into a cylindrical shape by butting the side parts of plural metallic pieces 11, 11'.... Said pieces 11, 11... consist of two kinds of adjacent metallic pieces 11a, 11b. The side parts to be butted of said pieces are made into the shape expanding respectively to the inside and the outside so that said parts are in close contact with each other; moreover, both ends fit into the grooves 13, 13 of stationary plates 12, 12 thereby forming a prescribed shape of a core. A jig 14 is provided in the cylinder of the core 10, and four arms 16, 16... pivoted freely rockably with push plates 17 at the respective top ends are fitted pivotally to the pipe 15 thereof, freely rockably at an equal space. Said parts are extended to expand forcibly the plates 11, 11... to the outside to engage the same strongly with the plates 12, 12, whereby the shape of the core 10 is maintained during casting. The arms 16, 16... are contracted and the pieces 11, 11... are disassembled and removed upon ending of the casting. |
