Patent ID: 9528374
Filing Date: 2016-12-27
CPC Classification: F01D,F04D

Claim Text:
1. A turbofan comprising: a circular main plate to be rotationally driven; an annular shroud disposed so as to face the main plate; and a plurality of blades that are each connected to the main plate at one end and to the shroud at the other end and that are disposed to be spaced apart in the circumferential direction of the main plate, the blades each having a blade trailing edge portion located on the outer peripheral side of the main plate, and a blade leading edge portion located closer to a center of rotation of the main plate than the blade trailing edge portion, wherein at least one of a pressure surface of the blade and a suction surface of the blade has a blade leading edge side jagged portion formed at a blade leading edge portion side of the blade, the blade leading edge side jagged portion extending substantially along the blade leading edge portion and being recessed in the thickness direction of the blade, and wherein in the blade leading edge side jagged portion, a plurality of cutout shapes are formed that are alternately protruded and recessed in a direction substantially perpendicular to the blade leading edge portion, a part from the vicinity of the blade leading edge portion to the vicinity of the blade trailing edge portion of at least one of the pressure surface of the blade and the suction surface of the blade is formed by a separate member, the separate member is fitted in a frame portion formed by the blade leading edge portion, the blade trailing edge portion, and a beam member that connects the blade leading edge portion and the blade trailing edge portion and that is thinner than the thickness of the blade, and the blade is thereby formed.