| 摘要 |
The diameter of each of a plurality of mountain fold-shaped sections (4a) of a bellows (4) decreases in a tapering manner with decreasing distance to an end portion (3a) of a heat carrier circulating tube (3). Likewise, the diameter of each of a plurality of valley fold-shaped sections (4b) decreases in a tapering manner with decreasing distance to the end portion (3a) of the heat carrier circulating tube (3). Specifically, each mountain fold-shaped section (4a) is formed so as to be positioned in a position that is offset in the radial direction of the bellows (4) from adjacent mountain fold-shaped sections (4a) and that is an approximately intermediate position (intermediate section) between the adjacent mountain fold-shaped sections (4a) and between adjacent valley fold-shaped sections (4b). Likewise, each valley fold-shaped section (4b) is formed so as to be positioned in a position that is offset in the radial direction of the bellows (4) from adjacent valley fold-shaped sections (4b) and that is an intermediate section between adjacent mountain fold-shaped sections (4a) and between the adjacent valley fold-shaped sections(4b). |
