Patent ID: 11885339
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 12:
13. 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,
each of the plurality of blade portions includes, in the axial direction of the rotary shaft, a front end part and a base part that is an end part on a side opposite to the front end part and is connected to the main plate,
in a case where a blade outer diameter of the base parts is defined as a first blade outer diameter C and a blade outer diameter of the front end parts is defined as a second blade outer diameter D, the plurality of blade portions have relationship of second blade outer diameter D>first blade outer diameter C,
in a case where a blade inner diameter of the base parts is defined as a first blade inner diameter E and a blade inner diameter of the front end parts is defined as a second blade inner diameter F, the plurality of blade portions have relationship of second blade inner diameter F>first blade inner diameter E, and
each of the plurality of blade portions has relationship of blade inlet angle θ≤90 degrees.