Abstract: A centrifugal blower is arranged in the casing so as to extend its axis of rotation along the depth direction of an air conditioner. A pair of heat exchangers are arranged on the right and left sides of the centrifugal fan so as to superimpose on the centrifugal fan when viewed from the direction perpendicularly intersecting the axis of rotation of the centrifugal fan. In other words, each heat exchanger is arranged symmetrically with respect to a vertical plane including the axis of rotation of the centrifugal fan. Accordingly, the centrifugal fan and the heat exchanger do not overlap in the depth direction of the air conditioner in the casing. Thus, the air conditioner can be made compact in the depth direction.

Abstract: A fan guard includes a plurality of extending ribs extending from a blocking plate to an outer frame, a plurality of inner ribs arranged between the extending ribs and extending from the blocking plate to the substantial center in the radial direction, and a plurality of outer ribs arranged between the extending ribs and extending from the substantial center in the radial direction to the outer frame. The number of the inner ribs is set smaller than the number of the outer ribs. Hence, strength to prevent bending of the fan guard due to load application in the axial direction is ensured and increase in ventilating resistance of forced airflow (W) from a blower fan is suppressed.

Abstract: A fan guard is composed of a planarity of extending ribs (17A, 17A . . . ) extending from a blocking plate (14) to an outer frame (15), a plurality of inner ribs (17B, 17B . . . ) arranged between the extending ribs (17A, 17A . . . ) and extending from the blocking plate (14) to the substantial center in the radial direction, and a plurality of outer ribs (17C, 17C . . . ) arranged between the extending ribs (17A, 17A . . . ) and extending from the substantial center in the radial direction to the outer frame (15). The number of the inner ribs (17B, 17B . . . ) is set smaller than the number of the outer ribs (17C, 17C . . . ). Hence, strength to prevent bending of the fan guard (4) due to load application in the axial direction is ensured and increase in ventilating resistance of forced airflow (W) from a blower fan (3) is suppressed.

Abstract: In an axial fan having a plurality of blades (2, 2, . . . ) around an outer periphery of a hub (1), a cross-sectional configuration of each of the blades (2) at an arbitrary distance from a center of the fan is set such that a blade thickness gradually increases moving away from a blade leading edge (2a) and then gradually decreases towards a blade trailing edge (2b). Also, if a length of a camber line extending from the blade leading edge (2a) to a position where the blade thickness becomes maximum is taken to be L, and a length of a camber line extending from the blade leading edge (2a) to the blade trailing edge (2b) at the arbitrary distance is taken to be L.sub.0, then L/L.sub.0 falls within a range of 0.27 to 0.35. Thus, the aerodynamic performance never lowers even if the inflow angle of air into the blade (2) varies.