US 12,258,975 B2
Impeller and centrifugal fan
Shinji Takemoto, Kyoto (JP); and Satoshi Kajikawa, Kyoto (JP)
Assigned to NIDEC CORPORATION, Kyoto (JP)
Appl. No. 17/914,422
Filed by Nidec Corporation, Kyoto (JP)
PCT Filed Feb. 26, 2021, PCT No. PCT/JP2021/007282
§ 371(c)(1), (2) Date Sep. 26, 2022,
PCT Pub. No. WO2021/199810, PCT Pub. Date Oct. 7, 2021.
Claims priority of application No. 2020-059389 (JP), filed on Mar. 30, 2020; application No. 2020-059469 (JP), filed on Mar. 30, 2020; application No. 2020-059603 (JP), filed on Mar. 30, 2020; and application No. 2020-059646 (JP), filed on Mar. 30, 2020.
Prior Publication US 2023/0109395 A1, Apr. 6, 2023
Int. Cl. F04D 29/30 (2006.01); F04D 29/44 (2006.01)
CPC F04D 29/30 (2013.01) [F04D 29/444 (2013.01)] 9 Claims
OG exemplary drawing
 
1. An impeller for a centrifugal fan that rotates about a central axis extending in an axial direction, the impeller comprising:
a hub portion expanding radially outward about the central axis; and
wings on a radially outer side of the hub portion; wherein
a cross-sectional shape of the wings in a circumferential direction is a wing shape;
the wings are fixed to a radially outer side of the hub portion provided around the central axis;
at least a portion of the wings extends radially outward farther on a first side in the axial direction than a surface on the first side in the axial direction of the hub portion;
an upper end of the wings in the axial direction is located closer to the first side in the axial direction than an upper end of the hub portion in the axial direction is;
the impeller does not include any main plate that supports the wings in an axial direction of the wings;
an axial position of an end portion on a first side in the axial direction of the wings changes from a radially inner side to a radially outer side; and
a ratio of (i) a distance from a radially innermost end portion of the wings to an axially uppermost portion of the wings to (ii) a distance from the radially innermost end portion of the wings to a radially outermost end portion of the wings is equal to: 60% to 75%.