| 摘要 |
PURPOSE: To improve the startability of a flange by disposing undercut mechanism at a side wall part of a rim used for a tire having a flange enabling flat tire travel, and communicating the undercut mechanism with atmospheric pressure through orifices. CONSTITUTION: A rim 1 is used for a tire 2 having a flange 3 enabling flat tire travel. The rim 1 has a groove 10 for receiving the flange 2. The groove 10 has U-shape center cross section with the recessed face turned radially outward and has a bottom part 101 parallel to a rotation axis. The groove 10 is partitioned by each side wall 102 extended radially outward in relation to the bottom part 101 on both axial sides. In such constitution, at least one undercut mechanism 11 is disposed at each side wall 102, and orifices 100 communicated with atmospheric pressure radially inward of each undercut mechanism 11 are disposed in the groove 10. |
