| 摘要 |
A blade front edge 4a of a turbo fan 1 has, between a main-plate-side blade front edge 4a1 and a shroud-side blade front edge 4a2, a projecting blade front edge 4a3 which distances away from a blade rear edge 4b (located in a rotation direction A) as it furthers away from a main plate 2 ,which curves to a position away from a rotation center O, and, in a range close to the main plate 2, a main-plate-side front-edge skirt portion 41a1 which distances away from the blade rear edge 4b and inclines away from the rotation center O as it becomes closer to the main plate 2. On the other hand, a main-plate-side blade rear edge 4b1, which is a range close to the main plate 2 of the blade rear edge 4b, is substantially perpendicular to the main plate 2 and a shroud-side blade rear edge 4b2, which is a range close to a shroud 3, is inclined so as to gradually distance away from the blade front edge 4a (behind in the rotation direction A) as it furthers away from the main plate 2. |
