| 摘要 |
PCT No. PCT/AU81/00181 Sec. 371 Date Jul. 14, 1982 Sec. 102(e) Date Jul. 14, 1982 PCT Filed Dec. 3, 1981 PCT Pub. No. WO82/01919 PCT Pub. Date Jun. 10, 1982.A stall-free axial flow fan (10) has an impeller (12) with a plurality of radially extending blades (14) enclosed in a tubular casing (11) divided into a inlet portion (15), an intermediate portion (16) of larger diameter than the minimum diameter of the inlet portion (15) and an outlet portion (17) of a diameter no larger than the minimum diameter of the inlet portion (15). Impeller (12) is positioned with the leading edge of each blade (14) protruding into the intermediate portion (16) and the trailing edge protruding into the outlet portion (17). Inlet portion (15) may contain a plurality of radially extending vanes (19) each rotatable about a spindle (20) and extending between the stator (18) and the inner wall of the inlet portion (15). Intermediate portion (16) may contain a plurality of fixed vanes (21) disposed radially of the stator (18) and axially of the casing (11). |
