| 摘要 |
PURPOSE:To improve precision by supporting an intermediate member having a plurality of annular recessed parts formed intermittently on the outer periphery of an element pipe which is made of a metal plate which is plastically deformable, with a core metal and an annular recessed part suppressing member, and reducing the axial direction length and the interval of the suppressing member by pressing the intermediate member in the axials direction from both the side ends, and outwardly bulging out the intermediate pert of the annular recessed part. CONSTITUTION:A cylindrical element pipe is formed out of a metal plate which is plastically deformable such as steel pipe, and an intermediate member 8 is formed by installing a plurality of annular recessed parts 7 intermittently in the axial direction over the whole periphery of the element pipe. A core metal 11 is inserted free from chattering into the intermediate member 8. Further, each annular recessed part 7 is pressed from outside by a plurality of pressing members 12 which are shiftable in the axial directions. The intermediate member 8 is pressed in the axial direction from both the side end parts, keeping the above-described suppressed state, and the length in the axial direction of the intermediate member 8 and the gap 17 between the suppressing members 12 are contracted, and the gap part is bulged outward in the diameter direction. Accordingly, a metal bellows can be manufactured by plastically deforming plural parts on the outer peripheral surface of the element pipe through the cold working by a relatively simple manufacturing device. |
