Patent ID: 11898563
Assignee: NIDEC CORPORATION
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 0:
1. An axial fan comprising:
a housing that surrounds a vertically extending central axis, and includes an upper housing in an axially upper portion and a lower housing in an axially lower portion;
an upper motor that is accommodated in the upper housing and rotates an upper impeller about the central axis; and
a lower motor that is accommodated in the lower housing and rotates a lower impeller about the central axis; wherein
the upper housing includes a cylindrical upper peripheral wall covering the upper impeller and the upper motor from a radially outer side;
the lower housing includes a cylindrical lower peripheral wall covering the lower impeller and the lower motor from the radially outer side;
the lower housing includes lower protruding portions and lower protrusions including at least a portion located radially inward from the lower protruding portions, the lower protruding portions and the lower protrusions extending axially upwards from an axially upper surface of the lower housing; or
the upper housing includes upper protruding portions and upper protrusions including at least a portion located radially inward from the upper protruding portions, the upper protruding portions and the upper protrusions extending axially downwards from an axially lower surface of the upper housing.