| 摘要 |
PROBLEM TO BE SOLVED: To provide a ring fan capable of effectively avoiding biting of foreign matters at a ring part.SOLUTION: A ring fan 3 rotatably arranged on an inner periphery of a shroud 2 via an annular chip clearance C comprises: plural blades 32 radially extending from a boss part 33 rotating around a center shaft 3a; a ring part 31 coupling tips of the plural blades 32; and plural rib-like protrusion parts 35 for exhausting foreign matters provided on an outer periphery faced to the chip clearance C of the ring part 31. The plural protrusion parts 35 are spaced in a circumferential direction at a posture inclined to the center shaft 3a. |
