FAN BOSS

PROBLEM TO BE SOLVED: To provide a fan boss inhibiting a blasting apparatus from being enlarged. SOLUTION: The fan boss 1 includes a boss fixing plate 90 and a boss body 2 which is installed between a boss fixing plate 90 of a fan 9 including an opposite plate opposing to the boss fixing plate 90 in an axial direction and a plurality of annularly arranged blades installed between the boss fixing plate 90 and the opposite plate, and a rotary shaft 931 of a drive device driving the fan 9, and which includes a rotary shaft insertion hole 202 through which the rotary shaft 931 is inserted. A hole side screw part 202a is disposed at an inner circumference surface of the rotary shaft insertion hole 202 and a shaft side screw part 931a is disposed at an outer circumference surface of the rotary shaft 931. The boss body 2 is attached to the rotary shaft 931 by a screwing section A1 in which the hole side screw part 202a and a shaft side screw part 931a are screwed, and at least a part of the screw section A1 is disposed at an axial direction inside of the fan 9. COPYRIGHT: (C)2011,JPO&INPIT