Fan guard for blower unit

A fan guard of a blower unit which is provided with, between a blocking plate (14) arranged at a central part and an outer frame (15) arranged at an outer periphery, a plurality of annular ribs (16, 16 . . . ) arranged coaxially in a radial direction at predetermined intervals with a center of the blocking plate (14) as a center, and a plurality of radial ribs (17, 17 . . . ) extending radially from the blocking plate (14) to the outer frame (15) and arranged at regular intervals in a peripheral direction, and which is mounted at an air outlet (9) of a blower unit (A) having a blower fan (3), characterized in that:

• the radial ribs (17, 17 . . . ) includes a plurality of inner ribs (17B, 17B . . . ) extending from the blocking plate (14) to a substantial center in the radial direction and arranged at regular intervals in the peripheral direction, and a plurality of outer ribs (17C, 17C . . . ) extending from the substantial center in the radial direction to the outer frame (15) and arranged at regular intervals in the peripheral direction, and
• the number of the inner ribs (17B, 17B . . . ) is set smaller than the number of the outer ribs (17C, 17C . . . ).