Patent ID: 11955876
Assignee: MIDEA WELLING MOTOR TECHNOLOGY (SHANGHAI) CO., LTD.
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F  H | IPC H

Claim 28:
29. A fan comprising:
a driving structure;
an impeller, comprising a cover plate installed on the driving structure, the cover plate being recessed in an axial direction of the impeller, and a diameter of the cover plate gradually increasing along an air inlet direction;
a wind hood, being covered on the impeller, and comprising an air inlet and an air outlet communicated to the air inlet; and
a diffuser, being located at one end of the impeller facing the air outlet, and the diffuser comprising:
a first protrusion connected to the driving structure, the first protrusion protruding in a direction of the wind hood, wherein a diameter of one end of the first protrusion adjacent to the cover plate is smaller than a diameter of another end of the first protrusion away from the cover plate, and
an inner ring arm connected to the first protrusion and an outer ring arm sleeved outside the inner ring arm, wherein the outer ring arm is smoothly and transitionally connected to the wind hood, and wherein the first protrusion, the inner ring arm, and the outer ring arm are coaxial,

wherein:
the wind hood, the cover plate, and the diffuser defines a wind tunnel, and
the wind tunnel comprises a variable section portion and an equal section portion, the variable section portion is arranged adjacent to the air inlet, and the equal section portion is arranged adjacent to the air outlet, and

wherein:
an inner wall surface of the wind hood comprises a first inner wall surface corresponding to the cover plate and a second inner wall surface corresponding to the first protrusion, the first inner wall surface protrudes from an outside of the wind hood to an axial direction of the wind hood, the second inner wall surface is recessed from an axis of the wind hood toward an outside direction of the wind hood, and along the air inlet direction, a diameter of the first inner wall surface and a diameter of the second inner wall surface gradually increase, and
the first inner wall surface, the second inner wall surface, an outer wall surface of the cover plate, an outer wall surface of the first protrusion, an outer wall surface of the inner ring arm, and an inner wall surface of the outer ring arm define the wind tunnel.