Patent ID: 9376917
Filing Date: 2016-06-28
CPC Classification: F01D,F02K,F04D,F05D,Y02T

Claim Text:
1. A fan rotor blade constructed of a composite material composed of thermosetting or thermosoftening plastic and reinforced liber to be utilized in a fan for introducing air into an engine flow passage formed in an inside of an engine case of art aircraft engine, the fan rotor blade comprising: a blade body that is constructed of the composite material and has a suction-side surface on one side thereof and a pressure-side surface on another side thereof; a blade root integrally formed at a base end of the blade body by the composite material and capable of being joined with a joint slot formed on an outer circumference of a fan disc of the fan; and a metallic sheath attached to a leading edge of the blade body so as to extend in a span direction for protecting the leading edge, wherein the sheath includes a sheath main body that gradually decreases in thickness toward a leading edge of the fan rotor blade and a pair of joint flanges integrally extended from both rear edges of the sheath main body, and is segmented into a sheath base segment on a base end side of the blade body and a sheath top segment on a top end side of the blade body, the sheath top segment smoothly continues from the sheath base segment, and is not longer than the sheath base segment along the span direction, a sheath length of the sheath along a chord direction of the fan rotor blade is gradually made larger from a base end toward a top end of the sheath, a sheath length “k” of the sheath main body along the chord direction is gradually made larger from the base end toward the top end of the sheath main body, each sheath length of the pair of joint flanges along the chord direction is gradually made larger from a base end toward a top end of said each of the pair of joint flanges, the sheath length “k” of the sheath main body at a position of 80% span from the base end of the sheath is 10% chord≦k≦60%/chord, a sheath length “m” of the sheath along an end edge of the fan rotor blade is 40% chord<m<60% chord.