US 12,344,391 B2
Electric propulsion device
Hironobu Yamakawa, Tokyo (JP); Kisho Ashida, Tokyo (JP); and Yuji Enomoto, Tokyo (JP)
Assigned to HITACHI, LTD., Tokyo (JP)
Filed by Hitachi, Ltd., Tokyo (JP)
Filed on Jun. 18, 2024, as Appl. No. 18/746,421.
Claims priority of application No. 2023-115359 (JP), filed on Jul. 13, 2023.
Prior Publication US 2025/0019086 A1, Jan. 16, 2025
Int. Cl. B64D 35/021 (2024.01); B64C 11/18 (2006.01); B64C 27/467 (2006.01); B64C 29/02 (2006.01); B64D 27/31 (2024.01); B64D 27/32 (2024.01); B64D 33/08 (2006.01); B64U 20/94 (2023.01); B64U 50/19 (2023.01); F04D 25/08 (2006.01); F04D 29/38 (2006.01); F04D 29/58 (2006.01); H02K 9/06 (2006.01)
CPC B64D 35/021 (2024.01) [B64C 11/18 (2013.01); B64C 27/467 (2013.01); B64D 33/08 (2013.01); B64U 20/94 (2023.01); F04D 25/082 (2013.01); F04D 29/384 (2013.01); F04D 29/386 (2013.01); F04D 29/5806 (2013.01); F04D 29/5846 (2013.01); H02K 9/06 (2013.01); B64C 29/02 (2013.01); B64D 27/31 (2024.01); B64D 27/32 (2024.01); B64U 50/19 (2023.01)] 4 Claims
OG exemplary drawing
 
1. An electric propulsion device comprising:
a propeller; and
a motor adapted to rotate the propeller,
wherein the propeller comprises a rotary boss secured to a rotating shaft of the motor, and a blade protruding radially outward from the rotary boss,
wherein the blade includes a base end portion with an airfoil continuously changing such that a trailing edge comes to be in parallel to the rotating shaft of the motor from a radially outer side to the rotary boss, in a vicinity of the rotary boss,
wherein, in an axial direction of the rotating shaft, the motor is disposed below the trailing edge of the base end portion such that an upper end portion of the motor faces the trailing edge of the base end portion,
wherein the base end portion of the blade has a curved surface having an opposing surface facing a housing of the motor and being concavely curved, and the blade forms a discharge angle which is a right angle with respect to a virtual plane orthogonal to the rotating shaft of the motor, and
wherein the motor is provided with a plurality of opening holes in a facing surface of the housing of the motor to which the base end portion of the blade faces, and
the plurality of opening holes are inclined with respect to an axial direction of the rotating shaft and is extended in a direction orthogonal to the curved surface.