| 摘要 |
PURPOSE:To effectively prevent the generation of flaw and crack in a rubber tube by forming a flat non-grooved part situated on at least the opening end side of a shell of the axial both end sides of a ring, and a locking structure for locking the other end side of a rubber tube with the shell which is situated closer to the center over the non-grooved part. CONSTITUTION:The outer circumferential surface of an outer ring 21 is formed of a flat non-grooved part 21A situated below each caulking part 6A on the opening end side of an outer shell 6 and a locking groove part 21B locking between each caulking part 6A of the outer shell 6 which is situated on the upper side (center side) of the non-grooved part 21A. Therefore, even when a rubber tube 7 repeats deformation in accordance with contraction and expansion of an air chamber A, the outer circumferential end part 7B of the rubber tube smoothly contracts with the non-grooved part 21A of the outer ring 21 near the position 7B1 with a comparatively wide contact area. Hence, the generation of flaw and crack near the position 7B1 in the outer circumferential end part 7B of the rubber tube 7 can be effectively prevented. |
