| 摘要 |
PROBLEM TO BE SOLVED: To achieve a structure that improves durability without generating particularly high stress even if one circumferential end face 34 and the other circumferential end face 36, which are disposed to have a discontinuous part 12a therebetween, contact each other strongly during operation.SOLUTION: One circumferential end face 34 and the other circumferential end face 36 are disposed to have a discontinuous part 12a therebetween. A support surfaces 35 on one end is a portion of one circumferential end face 34 that matches a rim 25 on an intermediate side in an axial direction. A support surface 37 on the other end is a portion of the other circumferential end face 36 that matches the rim 25 on the intermediate side in the axial direction. A gap in a circumferential direction existing between the support surface 35 on the one end and the support surface 37 on the other end is smaller than gaps in other portions, among gaps in the circumferential direction existing between the one circumferential end face 34 and the other circumferential end face 36. |
