Patent ID: 11933315
Assignee: SANYO DENKI CO., LTD.
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 0:
1. An axial fan comprising:
a motor;
an impeller configured to be rotated by the motor and send air in an air-blowing direction; and
a casing including a wind tunnel along the air-blowing direction,
wherein the impeller includes:
a cup-shaped base covering the motor; and
a plurality of blades mounted on an outer peripheral surface of the base,

the base includes an underside portion located upstream in the air-blowing direction,
an outer peripheral edge of the underside portion is chamfered as viewed in a cross section of the impeller along the air-blowing direction,
a wind receiving surface of each of the plurality of blades that is located upstream in the air-blowing direction includes a concave portion recessed toward a downstream side in the air-blowing direction,
a bottom point of the concave portion of the wind receiving surface is located downstream in the air-blowing direction relative to a first imaginary line perpendicular to the air-blowing direction, the first imaginary line being drawn in a radial direction from a joint position of each of the plurality of blades where the wind receiving surface of each of the plurality of blades and the outer peripheral surface of the base merge,
the bottom point is a downstream-most point in the air-blowing direction in a cross-sectional view of the impeller along the air-blowing direction, taken along a line passing through a center point of the base and extending in the radial direction, and
the bottom point is displaced from inward to outward in the radial direction, in going from upstream to downstream in the air-blowing direction, until reaching a radially central part of each of the plurality of blades.