US 11,885,339 B2
Turbo fan, air sending device, air-conditioning device, and refrigeration cycle device
Takuya Teramoto, Tokyo (JP); Hiroyasu Hayashi, Tokyo (JP); Atsushi Kono, Tokyo (JP); Ryo Horie, Tokyo (JP); Kazuya Michikami, Tokyo (JP); Takahiro Yamatani, Tokyo (JP); and Hiroshi Tsutsumi, Tokyo (JP)
Assigned to Mitsubishi Electric Corporation, Tokyo (JP)
Appl. No. 17/288,319
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
PCT Filed Oct. 30, 2018, PCT No. PCT/JP2018/040324
§ 371(c)(1), (2) Date Apr. 23, 2021,
PCT Pub. No. WO2020/090005, PCT Pub. Date May 7, 2020.
Prior Publication US 2021/0372411 A1, Dec. 2, 2021
Int. Cl. F04D 17/10 (2006.01); F04D 29/58 (2006.01); F24F 1/00 (2019.01); F04D 29/28 (2006.01); F04D 29/42 (2006.01); F04D 17/16 (2006.01); F24F 1/0022 (2019.01)
CPC F04D 17/10 (2013.01) [F04D 17/162 (2013.01); F04D 29/281 (2013.01); F04D 29/424 (2013.01); F04D 29/5826 (2013.01); F24F 1/0022 (2013.01); F05D 2250/52 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A turbo fan, comprising:
a main plate rotationally driven; and
a plurality of blade portions arranged at intervals in a circumferential direction on the main plate,
wherein
the plurality of blade portions include a plurality of first blade portions arranged on one of plate surfaces of the main plate, and a plurality of second blade portions arranged on another plate surface of the main plate,
in a case where, in each of the plurality of first blade portions, a length of a virtual straight line connecting a first inner peripheral end part positioned on a rotary shaft side in a radial direction of the main plate and a first outer peripheral end part positioned on an outer edge side of the main plate is defined as a first chord length, and in each of the plurality of second blade portions, a length of a virtual straight line connecting a second inner peripheral end part positioned on the rotary shaft side in the radial direction of the main plate and a second outer peripheral end part positioned on the outer edge side of the main plate is defined as a second chord length, the first chord length and the second chord length are not equal to each other at positions separated by a same distance from the main plate in the axial direction of the rotary shaft, and
in a case where
one of the plurality of first blade portions is defined as a first reference blade portion,
in the rotation direction of the main plate, among the plurality of first blade portions, the first blade portion disposed adjacent to the first reference blade portion in the circumferential direction is defined as a third blade portion,
when the rotary shaft is viewed in an axial direction, among the plurality of second blade portions, the second blade portion disposed at a position closest to the first reference blade portion in the circumferential direction of the main plate is defined as a fourth blade portion,
the first outer peripheral end part of the third blade portion is defined as a third outer peripheral end part,
the second outer peripheral end part of the fourth blade portion is defined as a fourth outer peripheral end part,
an advancing angle between the first outer peripheral end part of the first reference blade portion and the third outer peripheral end part of the third blade portion is defined as an angle θ3, and
an advancing angle between the first outer peripheral end part of the first reference blade portion and the fourth outer peripheral end part of the fourth blade portion is defined as an angle θ4,
a relationship of angle θ4≤±(angle θ3)/2 is established in the plurality of blade portions, and the first reference blade portion and the fourth blade portion are provided to intersect with each other with the main plate in between when the rotary shaft is viewed in the axial direction.